Hydrogen is now recognized as the primary alternative to fossil fuels due to its renewable, safe, high energy density and environmentally friendly properties. Efficient hydrogen production through water splitting has laid the foundation for sustainable energy technologies. However, when hydrogen production is scaled up to industrial levels, operating at high current densities introduces unique challenges. It is necessary to design advanced electrocatalysts for hydrogen evolution reaction (HER) under high current densities. This review will briefly introduce chal-lenges posed by high current densities on electrocatalyst, including catalystic activity, mass dif-fusion and catalyst stability. In an attempt to address these issues, various electrocatalyst design strategies are summarized in detail. In the end, our insights into future challenges for efficient large-scale industrial hydrogen production from water splitting are presented. This review is expected to guide the rational design of efficient high current density water electrolysis electro-catalysts and promote the research progress of sustainable energy.

Driven by mounting environmental apprehensions stemming from the over dependence on fossil fuels in energy and transportation sectors, extensive exploration into alternative energy sources, particularly biomass, has stimulated profound research on harnessing the potential of computational and mathematical techniques. This comprehensive survey delves into optimal models and strategies, unveiling their pivotal role in the design of biomass gasification processes.of hydrogen through biomass gasification. In this study, we aim to provide a comprehensive overview of the computational and mathematical techniques employed in optimizing biomass gasification processes, with a specific focus on enhancing hydrogen yield. Through an extensive literature review, various models and strategies will be examined, including thermodynamic analysis, kinetic modeling, reactor design, and process optimization. By uncovering the power of these techniques, we aim to contribute to the advancement of sustainable and efficient biomass utilization for the hydrogen-based future economy.This paper aims to provide an updated and comprehensive coverage of the investigations conducted on the potential of producing hydrogen from biomass through gasification. To achieve this, we incorporate the latest works that have utilized numerical modeling, simulation, optimization techniques, process heat integration, and co-generation in their studies. By encompassing these aspects, we aim to offer a broader and more in-depth re-appraisal of the subject matter. This will ensure that readers gain a holistic understanding of the advances made in the field and the potential for sustainable hydrogen production of biomass gasification.Through a meticulous re-appraisal and analysis of each subject, we can identify their respective strengths and areas that require further research effort. By thoroughly examining numerical modeling, simulation, optimization techniques, process heat integration, and co-generation, we can assess their effectiveness and applicability in the context of biomass gasification for hydrogen production. This analysis shed light on the areas where these techniques excel, as well as pinpoint limitations or gaps in current understanding. By identifying these areas, we can highlight the need for further research and development, enabling us to make significant advancements in biomass gasification processes and pave the way for a sustainable and efficient hydrogen-based future economy..

This study investigates the impact of thin flame combustor design on hydrogen flame characteristics and combustion performance through numerical simulations. Variations in flame shape and combustibility between 100% methane and 100% hydrogen combustion are analyzed. Three combustor header shapes (flat, concave, and convex) are modeled to assess their influence on flame behavior. Results show distinct flow patterns, with concave headers promoting strong central flows and convex headers dispersing the flow outward. Temperature field analysis indicates that hydrogen flames have higher temperatures and shorter quenching distances compared to methane flames. A comparative analysis of combustion products is conducted to evaluate combustion performance and NOx emissions. Consequently, the concave header has high combustibility and increases temperatures and NOx fraction in hydrogen combustion.

The growing importance of hydrogen as an energy carrier in a future decarbonized energy system has led to a surge in its production plans. However, the development of infrastructure for hydrogen delivery, particularly in the hard-to-abate sectors, remains a significant challenge. While the construction of new pipelines entails substantial investment, repurposing existing pipelines offers a cost-effective approach to jump-starting hydrogen networks. Many European countries are exploring the possibility of utilizing their current pipeline infrastructure for hydrogen transport. Yet, a critical aspect requiring extensive research is the expansion planning of these networks to accommodate increased capacity in the future. This study investigates the utilization of existing natural gas pipeline infrastructure for hydrogen transportation as a cost-saving measure. It explores two expansion strategies, namely pipeline looping and compression, for repurposing a segment of a 342 km x 36inch existing pipeline, from the Escravos – Lagos gas pipeline system (ELPS) in Nigeria, for hydrogen transport. Employing the Promax® process simulator tool, the study assesses compliance with the API RP 14E and ASME B31.12 standards for hydrogen and hydrogen-methane blends. Both expansion strategies demonstrate acceptable velocity and pressure drop characteristics for hydrogen blends of up to 40%. Additionally, the increase in hydrogen content leads to heightened compression power requirements until approximately 80% hydrogen in the blends for compression, and a corresponding extension in looping length until around 80% hydrogen in the blend for looping. Moreover, the compression option proves to be more economically viable for all investigated proportions of hydrogen blends for the PS1-PS5 segment of the Escravos – Lagos gas pipeline case study. The percentage price differentials between the two expansion strategies reach as high as 495% for a 20% hydrogen proportion in the blend. This study offers valuable insights into the technical and economic implications of repurposing existing natural gas infrastructure for hydrogen transportation.

In this work, oxygen-doped g-C3N4 mesoporous nanosheets (O-CNS) were synthesized via a facile recrystallization method with the assistance of H2O2. The crystal phase, chemical composition, morphological structure, optical property, electronic structure and electrochemical property of the prepared O-CNS samples were well investigated. The morphological observation combining with nitrogen adsorption-desorption results demonstrated that the prepared O-CNS samples possessed nanosheets-like morphology with porous structure. The O doping into g-C3N4 resulted in the augment of specific surface area, which could provide more active sites for photocatalytic reaction. Simultaneously, the visible-light absorption capacity of O-CNS samples was boosted owing to the regulation of O doping. The built energy level induced by the O doping could accelerate the migration rate of photoinduced carriers, and the porous structure was most likely to speed up the release of hydrogen during photocatalyic hydrogen process. Resultantly, the photocatalytic hydrogen production rate of the optimized oxygen-doped g-C3N4 nanosheets reached up to 2012.9 μmol•h-1•g-1, which was 13.4 times higher than that of bulk g-C3N4. Thus, the significantly improved photocatalytic behavior was imputed to the porous structure, the augment of active sites, and the enhancement of visible light absorption and charge separation efficiency.

In the transition towards sustainable energy sources, hydrogen has emerged as the predominant alternative after fossil fuels. This comprehensive literature review delves into the evolving landscape of hydrogen launching strategies within the energy market. Numerous countries have strategically initiated efforts to introduce products based on hydrogen, underscoring the global acknowledgment of the potential inherent in hydrogen. Despite witnessing significant growth in the adoption of hydrogen energy worldwide, impediments to its widespread commercialization persist. This review identifies key barriers, including cost structures, technical complexities, and marketing challenges, hindering the establishment of a robust hydrogen energy market. The article critically examines the actions already undertaken to harness hydrogen energy for commercial purposes, leveraging scientific insights and statistical data. By carefully examining the current state of hydrogen energy initiatives, the review highlights gaps in existing strategies that require thoughtful consideration. Insights derived from scientific and statistical analyses inform the identification of barriers and contribute to a nuanced understanding of the challenges faced in the journey towards hydrogen energy commercialization. Ultimately, the article presents a strategic proposal outlining marketing actions geared towards expediting the commercialization and widespread adoption of hydrogen energy. Grounded in a thorough review of existing literature and supported by scientific and statistical evidence, this comprehensive analysis offers valuable insights for stakeholders seeking to navigate the intricate landscape of hydrogen energy in the global energy market.

The present review revisits representative studies addressed to develop efficient carbon-based heterogeneous catalysts for two important reactions, namely, the production of hydrogen from formic acid and the hydrogenation of carbon dioxide to formic acid. The HCOOH-CO2 system is considered a promising couple for a hydrogen storage system that would be involved in an ideal carbon-neutral cycle. Significant advancements have been achieved in those catalysts designed to catalyze the dehydrogenation of formic acid under mild reaction conditions, while much effort is still needed to catalyze the challenging CO2 hydrogenation reaction. The design of carbon-based heterogeneous catalysts for these reactions encompasses both the modulation of the properties of the active phase (particle size, composition, and electronic properties), as well as the modification of the supports by means of incorporation of nitrogen functional groups. These approaches are herein summarized to provide a compilation of the strategies followed in recent studies to set the basis for a hydrogen storage system attained by the HCOOH-CO2 couple.

The gas molecules O2, NO, H2S, CO, CH4 , have been increasingly used for medical purposes. Beside these gas molecules, H2, the smallest diatomic molecule in nature, has become a rising star in gas medicine in the past few decades. As a non-toxic and easily accessible gas, H2 has shown preventive and therapeutic effects on various diseases of the respiratory, cardiovascular, central nervous and other systems, but the mechanisms are still unclear and even controversial, especially the mechanism of H2 as a selective radical scavenger. Mitochondria are the main organelles regulating energy metabolism in living organisms, as well as the main organelle of reactive oxygen species generation and target. We propose that the protective role of H2 may be mainly dependent on its unique penetrating ability to everywhere of the cells to regulate mitochondrial homeostasis by activating the Keap1-Nrf2 phase II antioxidant system, rather than its direct free radical scavenging activity. In this review, we summarize the protective effects and focus on the mechanism of H2 as a mitochondria-targeting nutrient by activating the Keap1-Nrf2 system in different disease models, and wish to provide a more rational theoretical support for the medical applications of hydrogen.

Electrocatalytic and photocatalytic hydrogen evolution reaction (HER) provides a promising approach to clean energy generation. Bimetallic single-atom catalysts raised and have been explored to be advanced catalysts for HER. It is urgent to review and summarize the recent advances in developing bimetallic single-atom HER catalysts. Firstly, the fundamentals of bimetallic single-atom catalysts are presented, highlighting their unique configuration of two isolated metal atoms on supports and resultant synergistic effects. Secondly, recent advances in bimetallic single-atom catalysts for electrocatalytic HER under acidic/alkaline conditions are then reviewed, including W-Mo, Ru-Bi, Ni-Fe, Co-Ag, and other dual-atom systems on graphene and transition metal dichalcogenides (TMDs) with enhanced HER activity versus monometallic analogs due to geometric and electronic synergies. Then, Photocatalytic bimetallic single-atom catalysts on semiconducting carbon nitrides for solar H2 production are also discussed. Finally, an outlook is provided on opportunities and challenges in precisely controlling bimetallic single-atom catalyst synthesis and gaining in-depth mechanistic insights into bimetallic interactions.

The very slow anodic oxygen evolution reaction (OER) greatly limits the development of large-scale hydrogen production via water electrolysis. By replacing OER with easier urea oxidation reaction (UOR), developing a HER/UOR coupling electrolysis system for hydrogen production can significantly save energy and costs. Al doped cobalt ferrocyanide (Al-Co2Fe(CN)6) nanocube array was in-situ grown on nickel foam (Al-Co2Fe(CN)6/NF). Due to the unique nanocube array structure and regulated electronic structure of Al-Co2Fe(CN)6, the as-prepared Al-Co2Fe(CN)6/NF electrode exhibited outstanding catalytic activities and long-term stability to both UOR and HER. The Al-Co2Fe(CN)6/NF electrode needed potentials of 0.169 V and 1.118 V (vs. reversible hydrogen electrode) to drive 10 mA cm−2 for HER and UOR, respectively, in alkaline condition. Applying the Al-Co2Fe(CN)6/NF to a whole urea electrolysis system, 10 mA cm−2 was achieved at a cell voltage of 1.357 V, which saved 60% electricity energy comparing to that of tranditional water splitting. Density functional theory calculations demonstrated that the boosted UOR activity comes from Co sites with Al doped electronic environments. This promoted and balanced the adsorption/desorption of main intermediates in UOR process. This work indicates that Co based materials as efficient catalysts have great prospects for application in urea electrolysis systems, and are expected to achieve low-cost and energy-saving H2 production.

The determination of critical ventilation flow rate is significant for the risk control and the standard development during accidental hydrogen leakage in a confined space with hydrogen-related equipment. In this paper, an analytical model for calculating critical ventilation flow rate was proposed through the quantification and constraint solution of ventilation effect and ventilation cost. The experimental method was used to investigate the effects of nozzle diameter and stagnation pressure on diffusion and ventilation for horizontal hydrogen leakage in a cuboid chamber. Ventilations from 30m3/h to 180m3/h were carried out through the rectangular vent. It was shown that the peak concentration of the measuring point is positively correlated with the stagnation pressure and the nozzle diameter. The experimental data are used to verify the analytical model by calculating the effective ventilation time. The study demonstrates that the critical ventilation flow rate can be increased significantly at higher stagnation pressures and larger nozzle diameters. And the discrepancy of critical ventilation flow rates under different nozzle diameters will be enhanced with the increase of stagnation pressure. For the stagnation pressure of 0.4MPa, the critical ventilation flow rate under 4mm nozzle even increases by 52% relative to the 2mm nozzle.

The two-component compound formed by codeine and cyclopentobarbital was produced by grinding techniques and by evaporation from alcoholic solutions. The cocrystal nature of this phase was established unequivocally by single crystal X-ray structure determination. The asym-metric unit contains one formula unit. In the cyclopentobarbital molecule, the cyclopentenyl ring is disordered over two positions related by a rotation of approximately 180° about its C‒C bond to the pyrimidine ring. The two NH groups of the cyclopentobarbital molecule form N—H···N and N—H···O bonds to piperidine and hydroxyl groups, respectively, belonging to different codeine molecules. In addition, the hydroxyl and methoxy groups of neighboring codeine molecules are linked by O—H···O interactions, resulting H-bonded framework structure of codeine and cyclo-pentobarbital molecules. The cocrystal was also characterized by thermal analysis, X-ray powder diffraction and IR spectroscopy.

Research has been actively conducted on the materials used to commercialize finished products that use hydrogen energy. Hydrogen embrittlement that occurs when hydrogen atoms penetrate metals is the largest problem that must be addressed first regarding safety. Because liquefied hydrogen has an 800 times higher density than hydrogen gas, hydrogen has been stored and transported through liquefaction at -253℃ using helium gas as a refrigerant. However, even if extreme temperatures below zero are maintained, natural vaporization loss that reduces liquefied hydrogen by 3 to 5% of the tank storage capacity per day occurs. In addition, when liquefied hydrogen is converted into high-pressure hydrogen gas for use, it is difficult to completely prevent the loss of the gas, even if sealing technology is applied to prevent gas leaks in transport and storage tanks. Therefore, methods to minimize the loss of hydrogen, establishment of assessment criteria for the embrittlement caused by a small amount of hydrogen gas, and related research are essential. We researched the hydrogen embrittlement resistance of SUS316L rods according to the tensile speed by conducting water electrolysis testing at room temperature, at which hydrogen gas is used to present hydrogen embrittlement assessment criteria for primary ring-shaped forged products.

Natural cellulose hydrogels have been widely used to enhance mechanical properties. However, existing natural fiber composite hydrogels are not reusable, limiting their potential applications. To address this issue, we designed and prepared a polyvinyl alcohol/glycerol /bamboo microfibril double network tough hydrogel using a simple method. The bamboo microfibril and polyvinyl alcohol form a tight and rigid network through hydrogen bonding, improving mechanical properties. The prepared polyvinyl alcohol/glycerol/bamboo microfibril double network tough hydrogel has the advantages of reusability and fatigue resistance. Furthermore, both the elastic modulus and toughness of the hydrogel increase with increasing bamboo microfibril content. We also demonstrated that the hydrogel can be recast after cyclic compression, maintaining its recyclability, stability, and certain stiffness and toughness. Our study highlights the potential of hydrogels for controllable mechanical properties, fatigue resistance and shows that polyvinyl alcohol/glycerol/bamboo microfibril hydrogel has broad value for plasticity and reuse.

Photocatalytic technology based on specific band structure of semiconductors offers a promising way to solve the urgent energy and environmental issues in modern society. In particular, hydrogen production from water splitting over semiconductor photocatalysts attracts great attention owing to the clean source and application of energy, which highly depends on the performance of photocatalysts. Among the various photocatalysts, TiO2 has been intensively investigated and used extensively due to its outstanding photocatalytic activity, high chemical stability, non-toxicity and low cost. However, pure TiO2 has a wide band gap of approximately 3.2 eV, which limits its photocatalytic activity for water splitting to generate hydrogen only under ultraviolet light, excluding most of the inexhaustible sunlight for human beings. Fortunately, the band gap of semiconductors can be manipulated, in which introducing oxygen defects is one of the most effective measures to narrow the band gap of titanium oxides. This review starts out by the fundamentals of photocatalytic water splitting for hydrogen production over TiO2, discusses the latest progress in this field, and summarizes the various methods and strategies to induce oxygen defects in TiO2 crystals. Then, the next section outlines the modification approaches of oxygen-deficient titanium oxide (TiO2-δ) to further improve its photocatalytic performance. Finally, a brief summary and outlook of the researches on TiO2-δ photocatalysts for water splitting to produce hydrogen were presented.

The most potential renewable energy source for global emissions reductions is green hydrogen production. Iraq is looking into several sources of alternative energy to lessen its dependency on fossil fuels and to considerably cut its carbon dioxide emissions. This research examined the conceptual framework for the production and consumption of green hydrogen in Iraq. On the basis of accessible official and public data from government agencies, the potential capabilities of renewable energy resources are assessed, and certain fair assumptions are also established for a full study and evaluation of a possible hydrogen production in the country. The data presented here demonstrate conclusively that the contributions of renewable energy to the production of green hydrogen are substantial, giving the country prominence in the area of green hydrogen production. A pathway for a green hydrogen economy in the country by 2050 is proposed by this research based on its analysis. It is distributed in three stages: green hydrogen as a fuel for industry; using green hydrogen for fuel cells; and hydrogen commercialization. On the other hand, the research found a number of challenges to the implementation of a green hydrogen production that can be used in Iraq and other developing countries, including technological, economic, and social problems in addition to the related policy consequences.

Several studies have shown that combining TiO2 and Cu2O enhances the photocatalytic activity of the material by generating a heterojunction capable of extending the light absorption in the visible and reducing the electron-hole recombination rate. Ball milling has been chosen as an alternative methodology for photocatalyst preparation, among the several techniques documented in the literature review. The results of a previously reported investigation enabled the identification of the most effective photocatalyst that can be prepared for hydrogen generation by combining Cu2O and TiO2 (i.e., 1%wt Cu2O in TiO2 photocatalyst prepared by ball-milling method at 200 rpm and 1 min milling time). To optimize photocatalytic hydrogen generation in the presence of the greatest photocatalyst, the effects of (i) sacrificial species and their concentration, (ii) temperature, and (iii) pH of the system are taken into account, resulting in a light-to-chemical energy efficiency of 8% under the best-tested conditions. Last but not least, the possibility of using the present photocatalytic system under direct solar light irradiation is evaluated: the results indicate that nearly 60% of the hydrogen production recorded under sunlight can be attributed to the visible component of the solar spectrum, while the remaining 40% can be attributed to the UV component.

Hydrogen plays a key role in the transition to a carbon-free economy. One of the areas of hydrogen use is the substitution of hydrocarbon fuel in gas turbine engines and power plants. This review article discusses the features of hydrogen combustion and their influence on the characteristics of combustion chambers in comparison with methane. The paper presents both the results of a study of pure hydrogen or methane and methane-hydrogen mixtures with different hydrogen content. Among the main features, it is worth noting a smaller ignition delay time and higher laminar flame speed with a shift in its maximum value to a rich mixture, which significantly affects on flashback inside burners premixer, especially at elevated air temperatures. Another feature is the increased temperature of the flame, which can lead to an increase in the rate of nitrogen oxides formation. However, wider combustion concentration ranges contribute to the stable combustion of hydrogen at temperatures lower than those of methane. Along with this, it was shown that even at the same adiabatic temperature, more nitrogen oxides are formed in a hydrogen flame than in a methane flame, which indicates an additional mechanism for NOx formation in addition to the Zeldovich mechanism. The article also summarizes some of the results of a study on the effect of hydrogen on the occurrence of thermoacoustic instability, which depends on the initial nature of pulsations during methane combustion. The presented data will be useful both to engineers who are engaged in solving the problems of designing hydrogen combustion devices, and to scientists in this field of study.

The photocatalytic hydrogen evolution reaction (HER) by water splitting has been studied, using catalysts based on TiO2 nanowires (TiO2NWs), which were synthesized by a hydrothermal procedure. This nanomaterial was subsequently modified by incorporating different loadings of gold nanoparticles (AuNPs) on the surface, previously exfoliated MoS2 nanosheets, and CeO2 nanoparticles (CeO2NPs). These nanomaterials, as well as the different synthesized catalysts, were characterized by electron microscopy (HR-SEM and HR-TEM), XPS, XRD, Raman, Reflectance and BET surface area. HER studies were performed in aqueous solution, under irradiation at different wavelengths, which were selected through the appropriate use of optical filters. The results obtained show that there is a synergistic effect between the different nanomaterials of the catalysts. The specific area of the catalyst, and especially the increased loading of MoS2 and CeO2NPs in the catalyst substantially improved the H2 production. Recyclability studies showed only a decrease in activity of approx. 7% after 15 cycles of use, which opens many possibilities regarding the potential use and scaling of these heterostructures in photocatalytic production of H2 from water.

The objective of this study is to design an optimal model predictive control (MPC) strategy using manipulated variables to control the production of a sufficient amount of hydrogen through low temperature autothermal reforming of dimethyl ether (DME), a reforming reaction performed using PdO/ZnO/γ-Al2O3 catalysts coated on honeycomb cordierite ceramics. Experiments and simulation have verified that the optimal activity temperature of the catalyst is 400 °C, and the hydrogen volume fraction in syngas is over 43%. In the implementation of the hydrogen production system, the MPC controller can precisely determine the feed rates of DME, high-purity air, and water based on the space state equation of the reformer, to achieve the anti-disturbance of the reformer temperature. Thus, the reduction of hydrogen yield and sintering of the catalyst as a result of overheating are prevented. As the static and dynamic performance of hydrogen production exhibits excellent tracking of the setpoints, an autonomous, automated, and reliable continuous system was designed to meet the desired hydrogen demand situation. This study shows that an autonomous, automated, and reliable continuous hydrogen production reforming system can be designed to actively respond to the on-board hydrogen usage situation.

In recent years, various optical measurement technologies such as far-infrared spectroscopy, low-frequency Raman spectroscopy, optical Kerr effect spectroscopy, and two-dimensional Raman-terahertz spectroscopy have developed vigorously. By comparing the complementary aspects detected by various linear and nonlinear spectroscopic techniques, a coherent picture emerges from studies of dynamics in water. Numerous molecular dynamics experiments and theoretical investigations have demonstrated low-frequency molecular motions in liquid water. For example, intermolecular hydrogen bond vibration, molecular reorientation motion, and the interaction between molecule/ionic solute and hydrogen bond all occur in the THz region, which are closely related to their physical/chemical properties and structural dynamics. However, precise probing of various modes of motion is difficult due to the complexity of the collective and cooperative motion of molecules and the spectral overlap of related modes. With the development of THz optical technology, current state-of-the-art THz sources can generate pulsed electric fields with peak intensities on the order of ~MV/cm. Such strong fields make it possible to use THz waves as the driving light source for nonlinear polarization of the medium, which in turn leads to the development of the emerging terahertz Kerr effect (TKE) spectroscopy technique. Many low-frequency molecular motion modes, such as the collective directional motion of molecules and the cooperative motion under the constraint of weak intermolecular interactions, are resonantly excited to unprecedentedly strong amplitudes driven by the THz electric field. Thereby the collected responses are increased. The TKE technique thus creates an interesting prospect for investigating low-frequency dynamics in these media. In view of this, this paper firstly summarizes the research work on the measurement mechanism of TKE spectroscopy by taking the solid material without low-frequency molecular dynamics process as an example. Starting from the principle of TKE technology and the exploration of the properties of solid matter using this technology, its application in the exploration of low-frequency molecular dynamics of liquid water and aqueous solutions is introduced. Liquid water is considered the building block of life and possesses many extraordinary physical and biochemical properties. Its hydrogen bonding network plays a crucial role in these properties. It is generally believed that the ability of water to form complex hydrogen-bonding networks is the main reason for its various kinetic and thermodynamic properties that are different from other liquids. However, the exact structure of the hydrogen-bonding network, the spatial extent of its existence, and the associated timescale are not known. And the relevant spectral information of the basic properties of the reaction water is still not known. Therefore, it is of great significance to evaluate the hydrogen bond-related kinetic properties of liquid water by optical means.

Martensitic steels are used at a wide range of strength levels in environments which expose them to hydrogen or water vapor over a large range of partial pressures and temperatures. Hydrogen can cause catastrophic failures under many seemingly benign conditions. The effect of hydrogen on the dimension stability of high strength martensitic steels under such conditions has been poorly understood, and existing models do not seem to adequately account for it. Experiments were conducted to measure the variation in volume due to the uptake of hydrogen of such steels under near-ambient conditions, and the results were compared to theoretical estimates derived from the density of defects acting as hydrogen traps. Based on these results a new model for hydrogen embrittlement was developed. The hydrogen lattice dilation (HLD) model isolates volume expansion as a primary driver of hydrogen embrittlement. It provides and distinguishes two modes of failure acceleration: the fast, brittle, stress-intensity independent cracking under higher static crack loading, and a slower, highly stress-intensity dependent tearing mode at lower stress intensity. The relationship between the two is explained, as is how hydrogen absorption by defects accounts for the crack threshold and crack velocity of each.

In the article, were checked influences of microaeration, pH, and VSS (Volatile Suspended Solid) for sour cab-bage anaerobic digestion. Results fermentation of sour cabbage under the condition of small oxygen addition are presented in this research can be classified as dark fermentation or hydrogenotrophic anaerobic digestion. The investigations were carried out for two concentrations 5 g VSS /L and 10 g VSS /L of sour cabbage at pH 6.0. The oxygen flow rates (OFR) for 5 g VSS /L were in the range of 0.53 to 3.3 mL/h for obtaining 2% to 8% of oxygen. In cases of low pH and microaeration, ethylene production was observed at a level below 0.05% in biogas. The highest volume of hydrogen for 5 g VSS/L was obtained for flow rate 0.58 O2 mL/h, giving hydrogen concentration in biogas in the range of 0 to 20%. For VSS 5 g/L and oxygen flow rate 0.58 mL/h; 0.021 L of hydrogen is produced per gram of VSS. In this case, VSS 10 g/L and oxygen flow rate 1.4 mL/h at pH 6.0, 0.03 L of hydrogen is generated per gram. Microaeration from 0.58 mL/h to 0.87 mL/h was propitious for hydrogen production at 5 g VSS/L of sour cabbage and 1.4 mL/h for 10 g/L. Another relevant factor is the volatile suspended solid factor of sour cabbage that caused optimal hydrogen production at VSS 89.32%.

The structural, elastic, anisotropic elastic, electronic, vibrational and properties of the Perovskite type Hydrides RbXH3 (X = Be, Ca, Mg) were performed via Vienna Ab – initio Simulation Pac-kage (VASP) based on Density Functional Theory (DFT). Our results have exhibited a well-agreement with previous calculations and experiments for each compound. In order to de-termine physical properties of RbXH3 has been used the Generalized Gradient Approximation (GGA) with Perdew-Burke-Ernzerhof (PBE) functional at this study. Present compounds were found to be mechanically stable as well as their gravimetric hydrogen storage capacities has been investigated. The Perovskite type Hydrides RbBeH3 and RbMgH3 has an indirect bandgap of 0.274 eV and 2.209 eV while RbCaH3 has a direct bandgap of 3.274 eV respectively and therefo-re these compounds has shown a semiconductor behaviour at equilibrium. Besides directional dependence of anisotropic properties was visualized by representing them with maximum - mi-nimum points..

In this work we explored how solvents can affect olefin oxidation reactions catalyzed by MCM-bpy-Mo catalysts and whether their control can be made with those players. The results of this study evidenced that polar and apolar aprotic solvents modulated the reactions in different ways. Experimental data showed that acetonitrile (aprotic polar) could hinder largely the reaction rate whereas toluene (aprotic apolar) did not. In both cases product selectivity at isoconversion was not affected. Further insights were obtained by means of neutron diffraction experiments, which confirmed the kinetic data allowing to propose a model based on substrate-solvent crosstalk by means of hydrogen bonding. In addition, the model was also validated in the ring-opening reaction (overoxidation) of styrene oxide towards benzaldehyde, which progressed when toluene was the solvent (reaching 31% styrene oxide conversion) but was strongly hindered when acetonitrile was used instead (reaching only 7% conversion), due to the establishment of H-bonds in the latter. Although this model was confirmed and validated for olefin oxidation reactions, it can be envisaged that it may also be applied to other catalytic reaction systems where reaction control is critical, while widening its use.

The Residential and Industrial zones as is, rely heavily, if not exclusively, on Hydrocarbons. Hydrocarbon thermal machinery such as Spark Ignition-Compression Ignition engines, Gasoline-Diesel generators, Coal-Lignite gasifiers, residential diesel-powered heating systems, Pyrolysis units and so on, are commonly met all around the planet. Such technology practically oxidizes Hydrocarbons to produce either heat, steam or useful mechanical work depending on the application, though energy losses are not, by any means, insignificant. Advanced material processing is an industrial sector who’s energy demand is significant and it is important for the general public to come to terms with the fact that by implementing Hydrogen technology to power such plant while at the same time improving the energy equilibrium of houses(advanced materials), communities would be taking major steps towards Climate Change effects debilitation. The downside of Hydrocarbon thermochemical exploitation can be described by the limited resources-reserves and the gaseous pollutant emissions (CO2, CO, NOx, SOx). In recent years, the Industrial zone as a whole has began taking a turn towards Electrification without having established the necessary infrastructure to support such a transition. Indicatively, at current rate of production, dead Lithium-Ion batteries are projected to reach as high as 11,000 metric tons by 2030, yet there is no recycling scheme in place, not to mention the prospect of that number rising even more, given the recent e-mobility trend. As it pertains to Electrification, such powertrains-machinery require electricity and a battery. Electricity production is mainly achieved through Coal-Lignite gasification, Batteries require metals, among others, for manufacturing, meaning that up-on mining, local water resources are contaminated, another very important ‘aspect’ of Lithium(per say) mining is that child labor is often associated with such processes, a truly despicable act. All of the above paint a crystal-clear picture as to how ‘environmentally friendly’ reckless-rushed Electrification really is. Climate Change is up-on us and it’s effects on the planet are obvious, the most important of which is glacier melting due to rising of the global Temperature. The COVID-19 crisis is a sign of what could come from glacier melting could as ice contains potentially harmful-toxic to humans, biological entities that are sure to be introduced to the general public if we were to continue exploiting mineral resources. Purpose of this paper is to provide a general overview of the technology around Hydrogen.

The study aimed to elucidate the optimum level of elemental sulfur, fresh cassava root (FCR), and urea and their effect on gas production, ruminal fermentation, thiocyanate concentration, and in vitro degradability. A 3×2×4 in a completely randomized design were conducted. Factor A was level of sulfur at 0%, 1%, and 2% of concentrate dry matter (DM), factor B was level of urea at 2% and 4% of concentrate DM, and factor C was level of the FCR at 0, 200, 300, and 400 mg of the total substrate. The study found that elemental sulfur, urea, and FCR had no interaction effect on the kinetics of gas, ruminal fermentation, hydrogen cyanide (HCN), and in vitro degradability. Elemental sulfur supplementation (P<0.05) significantly increased the gas produced from an insoluble fraction (b), in vitro DM degradability and either neutral detergent fiber or acid detergent fiber degradability, and propionate (C3) concentration while decreased the ruminal HCN concentration. Urea levels showed a (P<0.05) significant increase of the potential extent of gas production, ruminal NH3-N, and total volatile fatty acid (VFA). FCR supplementation (P<0.05) significantly increased the gas produced from an immediate soluble fraction (a), gas produced from insoluble fraction, gas production rate constant, total VFA, C3 concentration, and HCN while decreased ruminal pH, acetate, and butyrate concentration. It could be concluded that 2% elemental sulfur, 4% urea, and 300 mg FCR showed a greater effect on gas production, ruminal fermentation, and HCN reduction.

We investigated effects of molecular hydrogen (H2) supplementation on acid-base status, pulmonary gas exchange responses, and local muscle oxygenation during incremental exercise. Eighteen healthy, trained subjects in a randomized, double-blind, crossover design received H2-rich calcium powder (HCP) (1500 mg/day, containing 2.544 µg/day of H2) or H2-depleted placebo (1500 mg/day) for 3 consecutive days. They performed cycling incremental exercise starting at 20-watts work rate, increasing by 20 watts/2 min until exhaustion. Breath-by-breath pulmonary ventilation (VE) and CO2 output (VCO2) were measured and muscle deoxygenation (deoxy[Hb + Mb]) was determined via time-resolved-NIRS in the vastus lateralis (VL) and rectus femoris (RF). Blood gases' pH, lactate, and HCO3− concentrations were measured at rest and 120-, 200-, and 240-watt work rates. At rest, the HCP group had significantly lower VE, VCO2, and higher HCO3−, PCO2 versus placebo. During exercise, a significant pH decrease and greater HCO3− continued until 240-watts work rate in HCP. The VE was significantly lower in HCP versus placebo, but HCP did not affect the gas exchange status of VCO2 or oxygen uptake (VO2). HCP increased absolute values of deoxy[Hb + Mb] at the RF but not VL. Thus, HCP-induced hypoventilation would lead to lower pH and secondarily impaired balance between O2 delivery and utilization in the local RF during exercise, suggesting that HCP supplementation, which increases the at-rest antioxidant potential, affects the lower ventilation and pH status during incremental exercise. HPC induced a significantly lower O2 delivery/utilization ratio in the RF but not the VL, which may be because these regions possess inherently different vascular/metabolic control properties, perhaps related to fiber-type composition.

The study experimentally investigated a novel approach for producing hydrogen from methane cracking in dielectric barrier discharge catalytic plasma reactor using a nanocatalyst. Plasma-catalytic methane (CH4) cracking was undertaken in a dielectric barrier discharge (DBD) catalytic plasma reactor using Ni/MgAl2O4. The Ni/MgAl2O4 was synthesised through co-precipitation followed customised hydrothermal method. The physicochemical properties of the catalyst were examined using X-ray diffraction (XRD), scanning electron microscopy - energy dispersive X-ray spectrometry (SEM-EDX) and thermogravimetric analysis (TGA). The Ni/MgAl2O4 shows a porous structure spinel MgAl2O4 and thermal stability. In the catalytic-plasma methane cracking, the Ni/MgAl2O4 shows 80% of the maximum conversion of CH4 with H2 selectivity 75%. Furthermore, the stability of the catalyst was encouraging 16 hours with CH4 conversion above 75%, and the selectivity of H2 was above 70%. This is attributed to the synergistic effect of the catalyst and plasma. The plasma-catalytic CH4 cracking is a promising technology for the simultaneous H2 and carbon nanotubes (CNTs) production for energy storage applications.

Hydrogen evolution reaction (HER) is one of the most important reaction in electrochemistry. This is not only because it is the simplest way to produce high purity hydrogen and the fact that it is the side reaction in many other technologies. HER actually shaped current electrochemistry because it was in focus of active research for so many years (and it still is). The number of catalysts investigated for HER is immense, and it is impossible to overview them all. In fact, it seems that the complexity of the field overcomes the complexity of HER. The aim of this review is to point out some of the latest developments in HER catalysis, current directions and some of the missing links between a single crystal, nanosized supported catalysts and, recently emerging, single atom catalysts for HER

As a dominant mangrove species, Kandelia obovata is distributed in an intertidal marsh with an active H₂S release. Whether H₂S participates in the salt tolerance of mangrove plant is still ambiguous although increasing evidence have demonstrated that H₂S functions in plant responses to multiple abiotic stresses. In this study, as an H₂S donor, NaHS was used to investigate the regulatory mechanism of H₂S on salt tolerance of K. obovata seedlings using a combined physiological and proteomic analysis. The results showed that the reduction in photosynthesis (Pn) caused by 400 mM NaCl was recovered by the addition of NaHS (200 μM). Furthermore, the application of H₂S enhanced the quantum efficiency of PSII and the membrane lipid stability, implying that H₂S is beneficial to the survival of K. obovata seedlings under high salinity. We further identified 37 differentially expressed proteins by proteomic approaches under salinity and NaHS treatment. Among them, the proteins related to photosynthesis, primary metabolism, stress response and hormone biosynthesis were primarily enriched. The physiological and proteomic results highlighted that exogenous H₂S up-regulated photosynthesis and energy metabolism to help K. obovata to cope with high salinity. Specifically, H₂S increased photosynthetic electron transfer, chlorophyll biosynthesis and carbon fixation in K. obovata leaves under salt stress. Furthermore, the abundances of other proteins related to metabolic pathway, such as antioxidation (APX, CSD2, PDX1), protein synthesis (HSP, Cpn 20), nitrogen metabolism (GS2, GS1:1), glycolysis (PGK, TPI), AsA-GSH cycle were increased by H₂S under high salinity. These findings provide new insights into the roles of H₂S in the adaptations of mangrove plant K. obovata to high salinity environment.

This research paper presents a new application of electroactive polyimide doped with gold nanoparticles (PI/AuNPs) as a chemiresistor sensor for detecting hydrogen sulfide gas. The synthesis of PI/AuNPs was done in a simple 3-step process of polymerization using the as prepared amine-capped aniline trimer (ACAT), followed by imidization, and doping. Spectral analyses via FTIR, LC-MS and ¹H-NMR confirmed the formation of amine-capped aniline trimer with a MW of 288 g mol^-1. Comparison of ACAT, BSAA, and PI FTIR spectra showed successful polymerization of the last, while XRD validated the incorporation of metal nanoparticles onto the polymer matrix showing characteristic diffraction peaks corresponding to gold. Furthermore, TEM, and FE-SEM revealed the presence of well-dispersed Au nanoparticles with an average diameter of about 60nm. The electroactive PI/AuNPs-based sensor showed a sensitivity of 0.29% ppm^-1 H₂S at a linear concentration range of 50 to 300 ppm H₂S (r = 0.9777). The theoretical limit of detection was found at 0.142 ppm or 142 ppb H₂S gas. The sensor provided a stable response reading at an average response time of 43±5 seconds, which was easily recovered after an average time of 99±5 seconds. The sensor response was highly repeatable and reversible with RSD values of 8.88%, and 8.60%, respectively. Compared with the performance of the conventional conducting polyaniline also doped with gold nanoparticles (PANI/AuNPs), the fabricated electroactive PI/AuNPs exhibited improved sensing performance making it a potential candidate in monitoring H₂S in the environment and for work-related safety.

Background: Catalase is a vital antioxidant enzyme that dismutates H₂O₂ into water and molecular oxygen. Many protocols have been developed to measure catalase enzyme activity. Spectrophotometric methods are the most common assays that used to assess catalase enzyme activity. Methods: Because the rate-limiting step during catalase enzyme activity depends upon the dissociation of hydrogen peroxide, the developed assay measures the reaction between a hydroquinone/anilinium sulfate/ammonium molybdate reagent and Unreacted Hydrogen Peroxide, which results in the production of a purple, disubstituted quinone compound with a maximum absorbance value at 550 nm. Results: To clarify the precision of the developed method, the coefficients of variation were determined to be 2.6% and 4.7% for within run measurements and between run measurements, respectively. This method returned results that correlated well (r = 0.9982) with the results returned using the peroxovanadate method to assess catalase enzyme activity. Additionally, we examined the use of the newly developed hydroquinone assay to measure catalase enzyme activity in liver and bacterial homogenate samples. Conclusion: These results demonstrated that this assay can be used for scientific research and routine health applications because it is inexpensive, simple, accurate, and rapid. This method is suitable for use in clinical pathology laboratories because it is simple and produces precise and reproducible results.

The role of hydrogen in a future energy system with a high share of variable renewable energy sources (VRES) is regarded as crucial in order to balance fluctuations in electricity generation. These fluctuations can be compensated for by flexibility measures such as the expansion of transmission, flexible generation, larger back-up capacity and storage. Salt cavern storage is the most promising technology due to its large storage capacity, followed by pumped hydro storage. For the underground storage of chemical energy carriers such as hydrogen, salt caverns offer the most promising option owing to their low investment cost, high sealing potential and low cushion gas requirement. This paper provides a suitability assessment of European subsurface salt structures in terms of size, land eligibility and storage capacity. Two distinct cavern volumes of 500,000 m³ and 750,000 m³ are considered, with preference being given for salt caverns over bedded salt deposits and salt domes. The storage capacities of individual caverns are estimated on the basis of thermodynamic considerations based on site-specific data. The results are analyzed using three different scenarios: onshore and offshore salt caverns, only onshore salt caverns and only onshore caverns within 50 km of the shore. The overall technical storage potential across Europe is estimated at 84.8 PWh_H2, 27% of which constitutes only onshore locations. Furthermore, this capacity decreases to 7.3 PWh_H2 with a limitation of 50 km distance from shore. In all cases, Germany has the highest technical storage potential, with a value of 9.4 PWh_H2, located onshore only in salt domes in the north of the country. Moreover, Norway has 7.5 PWh_H2 of storage potential for offshore caverns, which are all located in the subsurface of the North Sea Basin.

MEMThe PdNi film hydrogen sensors with Wheatstone bridge structure were designed and fabricated by the micro-electro-mechanical system (MEMS) technology. The integrated sensors consisted of four PdNi alloy film resistors. The interval two of them were shielded with silicon nitride film and used as reference resistance, while the others were used for hydrogen sensing. The PdNi alloy films and SiN films were deposited by magnetron sputtering. The morphology and microstructure of the PdNi films were characterized with X-ray diffraction (XRD). The output resistance signal was converted to millivolt output voltage signal for easy data acquisition. Hydrogen (H2) sensing properties of PdNi film hydrogen sensor with Wheatstone bridge structure was investigated under different temperatures (30℃, 50℃ and 70℃) and H2 concentrations (from 10 ppm to 0.4%). The hydrogen sensor demonstrated good response at different hydrogen concentrations and high repeatability in cycle testing under 0.4% H2 concentration. Under 10ppm hydrogen, the PdNi film hydrogen sensor had evident and collectable output voltage of 600 μV.

Two types of heterometallic (Fe(III),Na) silsesquioxanes [Ph₅Si₅O₁₀]₂[Ph₁₀Si₁₀O₂₁]Fe₆(O^2‒)₂Na₇(H₃O⁺)(MeOH)₂(MeCN)_4.5.1.25(MeCN), I, and [Ph₅Si₅O₁₀]₂[Ph₄Si₄O₈]₂Fe₆Na₆(O^2‒)₃(MeCN)_8.5(H₂O)_8.44, II, were obtained and characterized. X-Ray studies established distinctive structures of both products, with pair of Fe(III)-O-based triangles surrounded by siloxanolate ligands, giving fascinating cage architectures. Complex II proved to be catalytically active in the formation of amides from alcohols and amines, thus becoming a rare example of metallasilsesquioxanes performing homogeneous catalysis. Benzene, cyclohexane and other alkanes, as well as alcohols, can be oxidized in acetonitrile solution to phenol, the corresponding alkyl hydroperoxides and ketones, respectively, by hydrogen peroxide in air in the presence of catalytic amounts of complex II and trifluoroacetic acid. Thus, the cyclohexane oxidation at 20 °C gave oxygenates in very high for alkanes yield (48% based on alkane). The kinetic behaviour of the system indicates that the mechanism includes the formation of hydroxyl radicals generated from hydrogen peroxide in its interaction with diiron species. The latter are formed via monomerization of starting hexairon complex with further dimerization of the monomers.

Background. IgA nephropathy (IgAN) is associated with chronic inflammation. Platelet-related parameters, such as platelet (PLT) count, platelet-to-albumin ratio (PAR) and platelet-to-lymphocyte ratio (PLR), were examined as potential prognostic indicators for renal and cardiovascular (CV) outcomes in IgAN. Methods. 150 IgAN patients were devided into two groups based on the cut-off value of PAR. All-cause mortality, major CV events and end-stage renal disease were the primary combined endpoints. Secondary endpoints, such as CV or renal endpoints, were also analyzed separately. Results. The patient’s mean age was 43.7 ± 13.5 years, and the follow-up time was 124 ± 67 months. The K-M curve showed that PLR, PAR and PLT were strongly associated with primary combined (p = 0.002, p = 0.004, p = 0.001) and renal outcomes (p < 0.001, p < 0.001, p < 0.001), but not with CV outcomes in IgAN. However, when combined with left ventricular hypertrophy (LVH) or metabolic syndrome (MetS) PAR was found to be a significant predictor of both primary (p < 0.001, p < 0.001) and secondary outcomes (p = 0.001 and p = 0.038; p = 0.001 and p = 0.015). Additionally, PLR correlated with microalbuminuria (r = -0.165, p = 0.033) and LVH (r = -0.178, p = 0.025), while PLT correlated with eGFR (r = 0.158, p = 0.040). Conclusion. Elevated PAR and PLR may predict progression to end-stage kidney disease, but in combination with LVH and MetS, they showed CV events also in IgAN. The determination of PAR and PLR can be useful and cost-effective parameters for assessing both cardiovascular and renal risks in CKD.

Background: The aim of this study has been to investigate if inflammatory biomarkers such as the systemic immune-inflammation index (SII), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) have any correlation with the recurrence of pleomorphic adenomas (PA) in patients afflicted by this disease. Methods: A retrospective multicentre study involving two Italian centres, the Maxillofacial Sur-gery at the Policlinico Federico II in Naples and the ENT and Maxillofacial Surgery at the IRCCS G. Pascale National Cancer Institute in Naples, has been performed. The study, involving 608 pa-tients who had received a diagnosis of PA, was conducted between January 2000 and January 2020. A Receiver Operating Characteristic (ROC) curve was used to calculate the optimal cut-off values for the SII, PLR and NLR. A linear regression model (LRM) and a non-linear logistic re-gression model (NLRM) were realized with respect to the NLR, PLR and SII. Results: The highest performance was achieved by the NLR (cut-off 2.960) with the AUC = 0.91, with an accuracy of 96.1%, sensitivity of 78.4% and specificity of 97.2%, PPV = 64.4% and NPV = 98.6%. The LRM and NLRM including all the haematological parameters did not increase the per-formance in terms of recurrence detection. Conclusion: The NLR is an excellent support tool in predicting the recurrence of PA with a cut-off of 2.960. It can be a good reference point for surgical decision-making and follow-up in clinical practice.

Let be a power function $f_{r,M}(s)$ defined for every $s$ within the finite set $M$ as follows $$f_{r,M}(s)= \begin{cases} s^r, \ &s\in M,\\ 0, \ &\mathrm{otherwise}. \end{cases} $$ Let a discrete convolution of $f_{r,M}(s)$ be denoted as follows $\mathrm{Conv}_{r,M}[n]=(f_{r,M}*f_{r,M})[n]$. Let a real coefficients $A_{m,j}$ be given by the following recurrence $$ A_{m,j} = \begin{cases} 0, & \mathrm{if } \ j<0 \ \mathrm{or } \ j>m, \\ (2j+1)\binom{2j}{j} \sum_{d=2j+1}^{m} A_{m,d} \binom{d}{2j+1} \frac{(-1)^{d-1}}{d-j} B_{2d-2j}, & \mathrm{if } \ 0 \leq j < m, \\ (2j+1)\binom{2j}{j}, & \mathrm{if } \ j=m. \end{cases} $$ In this paper we show that for every $n>0$ the following odd-power identities involving coefficients $A_{m,j}$ and convolution transform $\mathrm{Conv}_{r,M}[n]$ hold $$ \begin{split} n^{2m+1}+1&=\sum_{r=0}^{m}A_{m,r}\mathrm{Conv}_{r,\mathbb{N}}[n],\\ n^{2m+1}-1&=\sum_{r=0}^{m}A_{m,r}\mathrm{Conv}_{r,\mathbb{Z}_{>0}}[n],\\ n^{2m+1}&=\sum_{r=0}^{m}A_{m,r}\sum_{k=1}^{n} k^r(n-k)^r\\ &=\sum_{r=0}^{m}A_{m,r}\sum_{k=0}^{n-1} k^r(n-k)^r. \end{split} $$

Concern about the planet's future has motivated governments around the world to adopt policies that promote more responsible energy consumption. Reducing emissions of the principal cause of climate change man-made greenhouse gases requires greater system efficiency and the utilization of renewable energy sources. The generation of electricity is the single largest source of hazardous pollutants, followed by the transportation sector. This is true due to the extreme reliance on petroleum and its derivatives that these industries have. Electric mobility is receiving more attention from businesses, governments, and academic institutions as a means to reduce the negative impacts of current energy consumption. Without measures to address common technical issues, electric vehicles would strain electrical infrastructure. In order to determine the best strategy for switching operations and feeder reconfiguration, this research presents a helpful hybrid genetic algorithm particle swarm optimization (HGAPSO) method. Meet transmission limits while decreasing real power losses and enhancing the system's bus voltage profile. The effects of HGAPSO on power losses and voltage distributions in the network are analyzed. Then, a report is produced contrasting GA and PSO. This cross-breeding of GA and PSO led to HGAPSO. This important problem can be solved more effectively with the use of new or improved algorithms. To find the optimal reconfiguration and properly rearrange transmission network interconnection, it employs a plethora of heuristic optimization algorithms. The objective is to limit bus voltage variations while maintaining the system's radial topology and minimizing power usage. The reliability and performance of the procedure were evaluated using MATLAB's IEEE 33-bus communication network. The outcomes demonstrate the effectiveness of the proposed technique, which cuts down on power waste during standalone runs and speeds up the processing time.

Mobile robots can perform tasks on the move, including exploring terrain, discovering landmark features or moving a load from one place to another. This group of robots is characterized by a certain level of intelligence allowing making decisions and responding to stimuli received from the environment. As part of Industry 5.0, such mobile robots and humans are expected to co-exist and work together in a shared environment to make human work less tiring, quicker, and safer. This can only be realized when clean, dense, and economical energy sources are available. The aim of the study is to analyze the state of the art and to identify the most important directions for future developments in robotic power systems based mainly on batteries. The efficiency and performance of the battery depends on the design using different materials. Work environments and performance requirements are considered in this systematic review to classify solutions that help developers choose the best suited power system for specific application. Indirectly, the aim of the work is to generate discussion within the scientific and engineering community. A narrative review of publications from six major bibliographic databases according to preset inclusion criteria was combined with a critical analysis of current and future technologies. The main findings of the review allow answering question what is the role of modern power source technologies, artificial intelligence and ground-breaking research work in global policies related to energy saving, green policies, and sustainable development. The main opportunities and threats are discussed, and a brief feasibility analysis is carried out. Novelty of the article relates not only to the analysis of technologies, but also to approaches and their use under conditions of limited resource availability, when resource usage must be minimized. The article provides an overview of batteries, their specifications, classifications, and their advantages and disadvantages. In addition, we propose: (1) an algorithm for selecting main energy source for robot application, and (2) an algorithm for selecting electrical system power supply. Current mobile robot batteries are, in most cases, their biggest limitation. Progress in batteries development is too slow to catch up with the demand for robot autonomy and range requirements, limiting the development of mobile robots. Further intensive research and implementation work is needed to avoid years of delay in this area.

One of the most crucial and economically beneficial tasks for energy customer is peak load curtailment. On account of the fast response of renewable energy resources (RERs) such as photovoltaic (PV) units and battery energy storage system (BESS), this task is closer to be efficiently implemented. Depends on the customer peak load demand and energy characteristics, the feasibility of this strategy may warry. When adaptive neuro-fuzzy inference system (ANFIS) is exploited for forecasting, it can provide many benefits to address the above-mentioned issues and facilitate its easy implementation, with short calculating time and re-trainability. This paper introduces a data driven forecasting method based on fuzzy logic for optimized peak load reduction. First, the amount of energy generated by PV is forecasted using ANFIS which conducts output trend, and then, the BESS capacity is calculated according to the forecasted results. The trend of the load power is then decomposed in Cartesian plane into two parts, left and right from load peak, searching for BESS capacity equal. Network switching sequence over consumption is provided by a fuzzy logic controller (FLC) with respect to BESS capacity and PV energy output. Finally, to prove the effectiveness of the proposed ANFIS-based peak shaving method, offline digital time-domain simulations have been performed on a real-life practical test micro grid system in MATLAB/Simulink environment and the results have been experimentally verified by testing on a practical micro grid system with real-life data obtained from smart meter and also, compared with several previously-reported methods.

Penetration of grid connected inverters (GCI) has arisen in power systems due to increasing integration of renewable sources. However, restrictive grid codes require that renewable sources connected to the grid with power electronic systems must be properly connected and appropriate currents must be injected to support stability of the grid under grid faults. Simultaneous injection of symmetrical positive and negative sequence currents is mandatory to support stabilization of grid at the instant of grid faults. Conventional synchronously rotating frame dq current controllers are insufficient under grid faults due to low bandwidth of PI controllers. This paper proposes a new grid current control strategy for grid connected voltage source inverters under unbalanced grid voltage conditions. A proportional current controller with a first order low pass filter disturbance observer (DOb) is proposed which establishes positive sequence power requirements and independently control negative sequence current components under unbalanced voltage conditions. The method does not need any parameter, since it estimates nonlinear terms with low pass filter DOb. Simulations are implemented in Matlab/Simulink platform demonstrating the effectiveness of proposed method.

Background: Tuberculosis (TB) continues to be a serious public health threat that affects the most vulnerable population. Patients who are LTFU after TB diagnosis still represent one of the biggest challenges to TB control. Method: In this prospective observational study, we aimed to identify and analyse the risk factors associated with LTFU among TB patients who started first-line TB treatment in the Sanatorium Hospital in Luanda. Result: A total of 113 patients with TB were included between August 2018 and September 2019. Seventy-six (67.3%) patients were cured, 27 (23.9%) were LTFU, 5 (4.4%) died, 4 (3.5%) were transferred and 1 (0.9%) presented a treatment failure. After excluding those dead, transferred or who failed to treatment, we observed that severe TB at the time of diagnosis (OR 9.24, 95% CI 2.18-39.04) and food insecurity were significantly associated with LTFU (OR 5.96, 95% CI 1.66-21.41). Conclusion: The findings of our study are of enormous value to understand the reasons for the LTFU of patients with TB and can guide polices and facilitate designing measures to allow better adherence, and therefore, greater treatment success

Breast cancer (BC) affects millions of women; it is the leading cause of death by neoplasia in wom-en worldwide, with at least 500 thousand deaths each year, 70% of which occur in developing countries. Elastography evaluates tissue stiffness, making this a promising non-invasive real-time technique. BI-RADS is recognized as a standard and helpful technique for establishing BC risk. This study aimed to determine, by strain elastography (SE), the fat-to-lesion index (F/L index), sen-sitivity, specificity, and optimal cut-off to diagnose BC. This prospective study included 216 wom-en who underwent SE, ultrasound, mammography, and breast biopsy; according to mammogra-phy, we recruited BI-RADS category 2 (n= 5), category 3 (n=29), category 4 (n= 94), category 5 (n= 71) and category 6 (n=17); after biopsy, 108 women were classified as negative, and 108 were pos-itive for BC. Three expert BC radiologists performed all imaging interpretations and biopsies. Our results show mean values of the F/L index for negative biopsies of 3.70±2.57 and positive biopsies of 18.10±17.01; we developed two models for the prediction of BC, a logistic regression model with an AUC of 0.893 and a neural network with an AUC of 0.902. The Youden index yielded a F/L index cut-off >5.76, with a sensitivity and specificity of 84.26%. Positive Spearman's Rho cor-relation coefficient was observed between the F/L index and BI-RADS, r=.073 (p< 0.001). ANOVA test showed a difference between F/L index vs. molecular subtypes (p=0.002). SE is helpful as a di-agnostic complement to mammography, or in cases where the latter is contraindicated, elas-tography has an adequate predictive capacity and is a fast and minimally invasive procedure.

It has been proposed that upregulation of the noradrenergic (NA) system through exposure to novelty might be one of the key components for building cognitive reserve and resilience to neurodegeneration. A personality trait that promotes greater interest in novel experiences is Openness to Experience (OE). Individuals who are high in OE exhibit strong curiosity towards novelty and are more likely to be exposed to novel stimuli throughout the lifespan.Performing voxel-based morphometry analyses, we examined whether OE in 135 healthy young adults was associated with Locus Coeruleus (LC) - the main core of the noradrenergic system. We also investigated whether LC mediates the relationship between OE and a key measure of reserve, I.Q. In comparison with other neuromodulators’ seeds (Dorsal and Median Raphe [DR-MR] -5-HT, Ventral Tegmental Area [VTA] -DA- and Nucleus Basalis of Meynert [NBM] -Ach-), results show that greater LC integrity was related to greater OE and IQ. Additionally, mediation analyses revealed that only LC mediated the relationship between OE and IQ. Furthermore, a Bayesian multiple regression was conducted to model the contribution of both isolated and combined neuromodulator seeds to OE trait express. This approach found that the LC + VTA could account for more variance in OE expression compared to the LC alone. Other weaker but significant associations were observed between DR and OE, between LC + NBM and Conscientiousness and between DR + NBM and Extraversion. These results are together suggestive that OE is primarily underpinned by monoaminergic functioning, and that the LC-NA system plays a central role mediating the interdependence between OE expression and cognition (IQ level). While offering further understanding of the neurobiology of human personality, these findings indicate a pivotal role of LC-NA system integrity in novelty seeking in daily life. This provides a psychobiological account for how OE expression may be beneficial for maintaining the noradrenergic system to facilitate cognitive reserve and resilience to neurodegenerative conditions.

This paper compares the performance of three text-to-speech (TTS) models released from June 2021 to January 2022 in order to establish a baseline for Brazilian Portuguese. Those models were trained using dataset for Brazilian Portuguese. The experimental setup considers tts-portuguese dataset to fine-tune the following TTS models: VITS end-to-end model; glowtts and gradtts acoustic models both using hifi-gan vocoder. Performance metrics are arranged into objective and subjective metrics. As subjective metrics, the naturalness and intelligibility are measured based on the mean opinion score (MOS). Results shows that gradtts+hifigan model achieved naturalness of 4.07 MOS, close to performance of current commercial models.

Background: Vaccinating children against COVID-19 is an essential public health strategy in order to reach herd immunity and prevent illness among children and adults. Parents are facing tremendous stress in relation to the COVID-19 pandemic and the effectiveness of the COVID-19 vaccination program for children. In this study, we aimed to investigate parents’ willingness to vaccinate their children against COVID-19 in North Kivu province (DRC). Methods: A cross-sectional survey between December 01, 2021 to January 20, 2022 in 6 health zones (Goma, Karisimbi, Butembo, Beni, Kamango and Katwa) was conducted in the province of North Kivu. In each health zone, we selected 5 clusters (Health area) using the method of probabilistic selection proportional to population size. In total, 522 parents participated in our study. Results: Overall, 32.8% of parents intended to vaccinate their children. In the multivariate analysis, younger age of parents (aOR : 2.40, CI : [1.50-3.83]), higher level of fear that “a member of my family” could contract COVID-19 (aOR : 2.35, CI : [1.38-4.02]), higher level of perceived vulnerability to COVID-19 within the family (aOR : 1.70, CI : [1.005-2.2881]), higher level of perceived susceptibility to COVID-19 within the family (aOR : 3.07, CI : [1.80-5.23]), and history of vaccination against COVID-19 among parents (aOR : 16.47, CI : [8.39-32.33]), were significantly associated with the intention to have their children or adolescents vaccinated. Conclusion: Willingness of parents to vaccinate their children against the COVID-19 vaccination was low in North Kivu. There is undeniably in this region a need to reinsure the populations about vaccine safety for both children and adults. Public health authorities should also address widespread misinformation about vaccines in a timely manner.

With the COVID-19 pandemic continuing and the resulting economic burden increasingly apparent, the Indonesian government began to prepare a "new normal" phase and make peace with COVID-19. From this new decision arises the question of the readiness of businesses and the industrial sector to resume operations amid COVID-19. This article aims to provide concise and precise information about the preparations that can be made by businesses to operate safely amid COVID-19 based on existing scientific studies and literatures. From the literature visits it can be concluded that transmission and danger of a COVID-19 pandemic can be prevented through: creation of infectious disease prevention and response plan, implementing basic infection prevention measures, policies and procedures for proper identification and isolation of sick people, applying flexibilities in policies, and protections in the workplace.

Here we review and describe a set of research priorities to meet present and future challenges posed to farmed animal production that build on progress, successes and resources from the Functional Annotation of ANimal Genomes (FAANG) project.

South America has become the new epicenter of the coronavirus, especially in Brazil where the disease continues to spread exponentially across the country. This text aims to analyze the psychosocial factors of Covid-19 on back to school strategies in Brazil from a bioecological perspective. At the microsystem level, the population is experiencing different levels of stress and fear; at the mesosystem level, changes in routines, separation from family and friends, and closure of schools; and at the macrosystem level, national guidelines to control the pandemic, institutional standards on a national and international scale. Therefore, the main focus for the success of school return must be in the prevention of contagion and with physical and psychological health, and should not only consider the demands of curricula, financial or administrative management. For this reason, it is paramount that greater female representativeness is increased in decision-making levels of the meso and macrosystem, regarding the resumption of school and academic activities in the pandemic period, since the number of female leaders in decision-making, is still insufficient.

The COVID-19 pandemic has presented the world with increased challenges. The response to this pandemic has led to a sudden disruption of routine medical and elective surgical care. Most hospitals across the globe have had to change the way outpatient clinics are carried out and postpone non-urgent elective surgical procedures. NHS England ceased all elective general surgeries to train and re-deploy their staff to support the increased pressures from COVID-19 in an intensive care setting. However, with a decline of reported cases and deaths, the return to undertaking non-urgent elective services is imminent. In May 2020, Radha and Afzal published the first evidence-based guidelines for the resumption of elective orthopaedic services titled “Evidence based suggestions for the return to elective orthopaedic surgery following the COVID-19 Pandemic”. The pathway presented is adapted from the “Evidence based suggestions for the return to elective orthopaedic surgery following the COVID-19 Pandemic” and could potentially be used as a model for other surgical specialities. We present a three-phased return back to urological services. Safe resumption of elective care is possible but needs to be carefully planned.

Most large fibers in central nervous system of vertebrates are decussated. The cause or the evolutionary force of this phenomenon is not convincingly described. Here we show a pattern for this nervous system property that simultaneously is found to a more basic rule in evolution.The idea here is the "function to anatomy" theorem. We claim that functions of physical, biochemical, enzymatic, etc., in lower scale of living organisms "emerge" to anatomy in larger scales. And reversely, the anatomy we see in multicelular organisms are/were functions in microscopic scales.We propose descriptions, predictions, and a probable road map to what this can implicate in biological and medical issues.

In 2014, the outbreak of adenoviral pneumonia occurred in Korean military training center. However, there is limited data on characteristics of fever and its response to antipyretics therapy in immunocompetent adults with adenoviral positive community-acquired pneumonia (CAP). Medical records of patients who were admitted to Armed Forces Chuncheon Hospital for treatment of CAP between January 2014 and December 2016 were retrospectively analyzed. We evaluated demographics, clinico-laboratory findings and radiologic findings at admission were compared between adenovirus positive (Adv) group and adenovirus negative (non-Adv) group. Out of 251 military personnel with CAP during the study periods, 67 were classified into Adv group while 184 were Non-Adv group. Patients with Adv group had a longer duration of fever after admission and symptom onset. Adv group patients had a higher mean temperature at admission and more observed over 40 and 39 to 40℃. Adv group patients had more commonly observed no response to antipyretic treatment and adverse events after antipyretics use. Length of hospital stay had no significant difference between two groups and no patient died in both groups. In our study, Adv positive CAP in patients with immunocompetent military personnel had distinct characteristics of fever and response to antipyretic treatment.

An understanding of the cultural conditions that determine the factors affecting nurses’ intention to leave is important for countries suffering from nurse shortage. Aim: to examine factors influencing intention to leave among female hospital nurses in a large Japanese sample, classified into four generations by age considering economic conditions. Methods: a cross-sectional survey with convenience sampling was conducted. Anonymous self-administered questionnaires were distributed to all nurses in 30 hospitals. To assess intention to leave, basic attributes, life conditions, work characteristics, and factors of psychosocial work environment were addressed. After classifying data into four generations based on age cohorts, we conducted multivariate logistic regression analysis using the completed data (N = 5,074, mean age = 36.24). Results: regardless of generational characteristics influenced by economic conditions, effort and monetary reward were generation-common factors. Over-commitment, social support, and the presence of a role model were generation-common factors in three generations. While having children increased intention to leave in the generation born 1965–1979, having family members in need of caregiving other than children decreased the risk in the generation born in the 1980s. Conclusion: generational countermeasures considering factors of psychosocial work environment and life conditions are needed to avert female nurse turnover.

Microaggressions are subtle verbal and non-verbal slights based on group membership, and they are ubiquitous in the lives of racial minorities, women, and LGBTQ individuals (Sue, 2010). The goal of the current paper is to introduce a role-playing based exercise on effective responses to microaggressions. The workshop draws on the prejudice responding workshops of Plous (2000) and Lawson, et al. (2010) but integrates research-based strategies. The activity was tested in two groups of undergraduate students, and the findings suggested that both groups felt more prepared to deal with microaggressions after participating.

Monochromatic documents claim for much less computer bandwidth for network transmission and storage space than their color or even grayscale equivalent. The binarization of historical documents is far more complex than recent ones as paper aging, color, texture, translucidity, stains, back-to-front interference, kind and color of ink used in handwritting, printing process, digitalization process, etc. are some of the factors that affect binarization. This article presents a new binarization algorithm for historical documents. The new global filter proposed is performed in four steps: filtering the image using a bilateral filter, splitting image into the RGB components, decision-making for each RGB channel based on an adaptive binarization method inspired by Otsu's method with a choice of the threshold level, and classification of the binarized images to decide which of the RGB components best preserved the document information in the foreground. The quantitative and qualitative assessment made with 21 binarization algorithms in three sets of “real world” documents showed very good results.

HER2/neu positive breast tumors predict a high mortality and comprise 25-30% of breast cancer. We have shown that Flavokawain A (FKA) preferentially reduces the viabilities of HER2 overexpressing breast cancer cell lines (i.e. SKBR3 and MCF7/HER2) versus those with less HER2 expression (i.e. MCF7 and MDA-MB-468). FKA at cytotoxic concentrations to breast cancer cell lines also has minimal effect on the growth of non-malignant breast epithelial MCF10 cells. FKA induces G2M arrest in cell cycle progression of HER2 overexpressing breast cancer cell lines through inhibition of Cdc2 and Cdc25C phosphorylation and down-regulation of Myt1 and Wee1expression leading to increased Cdc2 kinase activities. In addition, FKA induces apoptosis in SKBR3 cells by increasing the protein expression of Bim and BAX and decreasing expression of Bcl₂, Bcl_x/L , XIAP and survivin. FKA also down-regulates the protein expression of HER-2 and inhibits AKT phosphorylation. Herceptin plus FKA treatment leads to enhanced growth inhibitory effect on HER-2 overexpressing breast cancer cell lines through down-regulation of Myt1, Wee1, Skp2, Survivin and XIAP. Our results suggest the promise of FKA as a novel apoptosis inducer and G2 checkpoint abrogating agent in combination with Herceptin for treatment of HER2 overexpressing breast cancer.

Rapid increase in urbanization and industrialization due to increase in human population has led to increase in global warming resulting to climate change that affects the ecosystem. Unusual natural disasters such as cyclones, storms, floods, weather fluctuations, rising seal levels, transitional ecosystems and coastal disruptions are major adverse effects of climate change. There are huge worrisome concerns and uncertainties about the future of the planet earth due to climate change caused by high carbon emissions. Global aggressive policies in control of Carbon-dioxide (CO2) emissions from several combustion mechanisms have paved way for alternative/ clean energy sources. Green hydrogen is a promising means of clean energy sources for commercial power generation stations and other crucial systems such as hydrogen fuel cell vehicles (HFCVs) , motors, drives, backup power for buildings, and also serving as a source of electrical energy for remote locations. The goal of this study is to review the current level of Sub-Saharan African nations’ preparedness to adopt green hydrogen as a way to mitigate local energy supply issues and strengthen their individual economies.

Carbon supported nanoparticles of monometallic Ni catalyst and binary Ni-Transition Metal (Ni-TM/C) electrocatalytic composites were synthesized via chemical reduction method, where TM stands for the doping elements Fe, Co, and Cu. The chemical composition, structure and morphology of the Ni-TM/C materials were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy (EDS). The electrochemical properties towards hydrogen oxidation reaction in alkaline medium were studied using the rotating disc electrode and cycling voltammetry methods. A significant role of the TM dopant in the promotion of the hydrogen electrooxidation kinetics of the binary Ni-TM/C materials were revealed. A record-high in exchange current density value of 0.060 mA cm²_Ni was measured for Ni₃Fe₁/C, whereas the monometallic Ni/C counterpart has only shown 0.039 mA cm²_Ni. In order to predict the feasibility of the electrocatalysts for hydrogen chemisorption, density functional theory was applied to calculate the hydrogen binding energy and hydroxide binding energy values for bare Ni and Ni₃TM₁.

Neutrophil to lymphocyte ratio (NLR) is a promising predictive and prognostic factor in breast cancer. We investigated its ability to predict disease-free survival (DFS) and overall survival (OS) in patients with luminal A or luminal B-HER2-negative breast cancer who received neoadjuvant chemotherapy (NACT). Pre-treatment complete blood cell counts from 168 consecutive patients with luminal breast cancer were evaluated to assess NLR. The study population was stratified into NLRlow or NLRhigh according to a cut-off value established by receiving operator curve (ROC) analysis. Data on additional pre- and post-treatment clinical-pathological characteristics were also collected. Kaplan-Meier curves, log-rank tests, and Cox proportional hazards models were used for statistical analyses. Patients with pre-treatment NLRlow showed a significantly shorter DFS (HR 6.97, 95% CI 1.65-10.55, p= 0.002) and OS (HR 7.79, 95% CI 1.25-15.07, p= 0.021) compared to those with NLRhigh. Non-ductal histology, luminal B subtype, and post-treatment Ki67≥ 14% were also associated with worse DFS (p= 0.016, p= 0.002, and p= 0.001, respectively). In multivariate analysis, luminal B subtype, post-treatment Ki67≥ 14%, and NLRlow remained independent prognostic factors for DFS, while only post-treatment Ki67≥ 14% and NLRlow affected OS. The present study provides evidence that pre-treatment NLRlow helps identify women at higher risk of recurrence and death among patients affected by luminal breast cancer treated with NACT.

During the conceptual and preliminary design stage of a ship, designers need to ensure that the selected principal dimensions and parameters are good enough to deliver a stable ship (statically and dynamically) besides deadweight and speed. To support this, the initial intact stability of the proposed ship is required to be calculated, and in doing so, the lightship weight and its detailed breakdown are necessary to be known. After hull steel weight, machinery weight, mainly, marine propulsion and power generation machinery, play a vital role in the lightship weight estimate of a ship due to its robustness. The correct estimation of respective weights improves the accuracy of calculating a ship's initial stability typically to be designed and built. Hence, it would be advantageous for the designer to convince the ship owner. A total of 3006 marine propulsion (main marine diesel) engines and 348 power generation (auxiliary marine diesel) engines/generators of various power output (generators output for auxiliary engines), engine RPM and cylinder number of different engine makers are collected. These are analyzed and presented in both tabular and graphical forms to demonstrate the possible relationship between marine propulsion engine weight and power generation engine weight, and their respective power output, RPM, cylinder number, power-RPM ratio and power-RPM ratio per cylinder.In this article, the authors have attempted to investigate the behavior of marine propulsion engine weight and power generation engine/generator weight regarding engine power output, generator power output, engine RPM and cylinder number (independent variables). Further attempts have been made to identify those independent variables that influence the weight of the marine propulsion engine and power generation engine/generator (dependent variables), and their interrelationships. A mathematical model has thus been developed and proposed, as a guiding tool, for the designer to estimate the weight of main and auxiliary engines more accurately during the conceptual and preliminary design stage.

Given the imperative of security, sustainability of supply, strategic considerations, and energy independence, there is a widely acknowledged need to persist in utilizing coal as the primary fuel for electricity generation in power plants. However, in order to combat the rising levels of CO2 in the atmosphere, it is crucial to advance the development of carbon capture and storage (CCS) technologies that enable fossil fuel power plants to achieve zero emissions. These technologies play a pivotal role in capturing and effectively storing CO2, thus ensuring that coal-based power generation can continue while significantly reducing its environmental impact. By implementing CCS solutions, fossil fuel power plants can transition towards a more sustainable and environmentally friendly energy future.The utilization of chemical solvents for CO2 absorption, coupled with long-term storage, presents an intriguing and commercially viable technology for CO2 capture. However, the significant energy demands of the solvent regeneration process necessitate optimization, particularly in large-scale power plants. While the current cost of CO2 capture stands at approximately #55,000.00(Naira) per ton of CO2, the objective is to reduce this cost to below #25,000.00(Naira) per ton of CO2. This reduction in cost is essential to ensure the economic feasibility and widespread adoption of CO2 capture technologies in power generation.This research paper explores various approaches to address the energy demands associated with amine scrubbing integration in a commercial power plant. It provides a comprehensive analysis, both technically and economically, of the performance of these different approaches. While some of the proposed schemes may result in minor efficiency reductions, the key objective is to calculate the specific cost per ton of CO2 captured. The primary focus is on identifying the most suitable configuration to implement large-scale, cost-effective schemes that can serve as a foundation for CO2 capture demonstration projects. By determining the optimal configuration, this research aims to pave the way for the successful implementation of efficient and economically viable CO2 capture technologies in the power generation sector.

Currently, one of the main focuses of attention in academia is microgrids (MGs) and their ability to maintain stable, resilient, reliable and high–power quality operations. A crucial component in MGs is power converters (PC), which facilitate the decentralization of power generation. This decentralization, however, poses challenges in terms of power quality. This paper presents a microgrid model based on the IEEE 14–bus distribution system and aims to investigate the power quality when the MG operates while connected to the conventional power grid. The MG model has been developed using MATLAB–Simulink®, a specialized tool for electrical engineering simulations. The results obtained are subjected to rigorous analysis and compared with the compatibility levels established by the IEEE–519 standard. This approach allows an accurate assessment of the MGs’ ability to maintain power quality at acceptable levels while interconnected to the conventional power grid. Finally, this study provides a valuable contribution to the MGs’ field of microgrids by providing a detailed and quantitative assessment of power quality, which will aid in the design and optimization of MGs’ for effective implementation in real electric power systems.

Improving performance and promoting sustainability in women's handball are key objectives to maximize the potential of female players and ensure the long-term viability of the sport. In this context, training with Olympic movements and their derivatives improves the development of strength, power, and speed, which are determinants of performance in team sports. The aim of this study was to determine if training with Olympic movements produces significant improvements in jumping, throwing, sprinting, and change of direction performance in women handball players. Twenty-one female handball players participated in the study (10 for the control group and 11 for the intervention group). Age ranged from 15 to 17 years. All participants performed four assessment tests (Abalakov Test, throw test, 20-meter Sprint and V-Cut Test) to determine jump height, throwing speed, running speed, and change of direction ability. Measurements were carried out before and after the intervention. For six weeks, the control group performed the strength work established by the club twice a week while the intervention group additionally performed training with Olympic movements. Significant differences (p &lt;0.05) were found between the pre and post measurement of the control group and the intervention group in jump height, throwing speed and running speed, being higher in the intervention group. For the change of direction, no significant differences were found. Between groups, significant differences were observed at the end of the intervention for jump height and running speed. The conclusion of this study was that, by training with Olympic movements, in addition to regular training, could produce greater improvements in jumping performance, throwing speed and running speed in female handball players.

This article presents a proposed system that enables energy transfer from the dc grid to a single-phase onboard grid, operating at an hi frequency. In addition to the energy transfer function, it additionally enables compensation of reactive power in the ac grid when the converter operates at less than rated power. To operate in compensator mode, it is necessary to decouple the current from the grid into active and reactive components and control them independently. To achieve good dynamics, synchronizers that operate in the dq system are used. In the case of a single-phase grid, it requires such a synchronizer to generate virtual quadrature signals. The used systems based on second-order generalized integrator are good, but to improve dynamics in the work a quadrature generator based on trigonometric calculations was proposed. The developed system was implemented in a proportional resonant current control system. Tests performed in steady state and in dynamic states related to typical grid disturbances showed better dynamic properties than the standard integrator-based system.Keywords: power transfer; compensator; P+R controller

The design of highly efficient sensitizers is one of the most significant areas in dye-sensitized solar cell (DSSC) research. We have studied a series of benzothiadiazole-based D-π-π-A organic dyes, putting emphasis on the influence of the donor moiety on the DSSC’s efficiency. Using linear response time-dependent density functional theory (TDDFT) with the CAM-B3LYP functional different donor groups were characterized in terms of electronic absorption spectra and key photovoltaic parameters. As a reference a dye has been considered which has a benzothiadiazole fragment linked via thiophene rings to a diphenylamine donor and a cyanoacrylic acid acceptor. The different systems are first studied in terms of individual performance parameters, which are eventually aggregated into the power conversion efficiency. Here only the amino-substituted species shows a modest increase, whereas the dimethylamino case even shows a decrease.

Power generation using renewable technologies has become a primordial option to satisfy the energy demand all over the world, being solar concentrating technologies widely applied for this purpose. A combination of Parabolic Trough Collector with Direct Steam Generation has been considered an excellent option for power generation, due to the economic cost and complexity in the plant are reduced. The thermal evaluation of the solar power plant as well as the PTC in the DSG process is very important in viability and economic analysis. In this sense, as the main objective of this work, a numerical tool for evaluating DSG with PTC technology has been developed. The software SOLEEC is a versatile, reliable, accurate and friendly to the user for thermally evaluating a DSG with PTC technology. The user has the possibility to compare the thermal behavior of different geometrical dimensions for a PTC; and even consider different materials; in order to satisfy the demand of superheated steam by a DSG process. The software has an error less than 5% when compared with literature results and in this paper is used to evaluate a power plant in Mexico obtaining that the change to DSG proposing different PTC could reduce the solar field about 35%.

The growing need to use renewable sources and the current difficulty in spreading the electricity grid in a widespread manner raise the question of how to respond to the need for more electricity immediately. The idea behind this study is to power a horizontal axis wind turbine with the air flow generated for cooling a stationary internal combustion engine. The power extracted from this solution is significantly lower than that of the internal combustion engine (about 0.3%) and could be advantageous only in limited contexts. Installation costs are limited because many elements deriving from wind variability can be removed or simplified.

This study analyzes the correlation between the lifetime and the rest energy of the unstable particle states with a lifetime greater than the zeptosecond (10⁻²¹ s), using data available from the Particle Data Group. This set of states seems to be divided into three groups, in each of which the two quantities can be correlated through a remarkably accurate power law. Although this fact does not represent anything new compared to the predictions of the Standard Model, it nevertheless reveals an unexpected order structure in the set of particle decays, emerging from such predictions.

We consider a control problem for a diffusive PDE model of heterogeneous population of thermostatically controlled loads (TCLs) aiming to balance the aggregate power consumption within a given amount of time. Using the Green’s function approach, the problem is formulated as an approximate controllability problem for a residue depending on control parameters nonlinearly. A sufficient condition for approximate controllability is derived in terms of initial temperature distribution, operation time of TCLs and threshold value of the aggregate power consumption. Case studies allow to reveal the advantages of the proposed solution from numerical calculations point of view.

Purposely slow velocity resistance exercise (i.e., 10 s concentric and eccentric phases) is a popular training method, but limits the loads that can be lifted (e.g., <50% 1 RM). This study compared the biomechanical properties of purposely slow velocity (SLOW) and traditional resistance exercise (TRAD) that uses maximal lifting velocities. Healthy resistance-trained men (n=5) performed two testing sessions (barbell squat and bench press) in random-order; a SLOW session (1 set x 10 repetitions at 28% 1 RM, 10 s concentric & eccentric), and a TRAD session (3 x 10 at 70% 1 RM, controlled eccentric and maximal concentric). A force plate and linear position transducer were used to collect kinetic and kinematic data for every repetition of both protocols (α = 0.05). For both exercises, both concentric and eccentric mean force (N) and power (W) for each repetition was greater for TRAD. When the entire training session (squat + bench press) was examined, SLOW exhibited greater time under tension, while TRAD produced greater work (J) and impulse (N·s). Contrary to suggestions in both the lay and scientific literature, purposely slow resistance exercise produced less force, power, and work than traditional velocity resistance exercise.

For the particular selected type of fractals, i.e., the Kronecker product based fractals, the introductory common classification is proposed. It essentially relies on the size and content of the initial fractal matrix. In turn, it gives one of the possible explanation of the phenomenal ability to produce a few of the most popular fractals using many different algorithms, languages and tools. Also, it paves the way to discover on the regular basis thousands of the new fractals, and this gives researchers a wider range of fractal models to choose from.

There are several challenges on how to attain energy efficiency while maintaining balance among factors affecting energy consumption such as power rating and temperature setpoints of cooling units, room temperature and humidity, and indoor air quality (IAQ). A real-time energy and IAQ monitoring system were installed in an educational building to profile the operational power consumption of inverter-based air condition unit (ACU) installed in each room. Polynomial curve and neural fitting regression analysis were applied to the real-time power consumption, indoor temperature and humidity, and carbon dioxide (CO2) level data. The derived models were able to provide the stabilizing indoor thermal and air conditions of the room to reach steady state ACU power consumption. These collected data and calculated parameters can be used to define rules in automating control of cooling appliances for an efficient energy utilization. The regression approaches, using real-time data, have determined the influence of indoor heat conditions and carbon dioxide levels on ACU power consumption. These parameters were utilized to establish consistent values for temperature, humidity, and carbon dioxide levels under stable settings of inverter-based air conditioning units.

Ultralight power generation equipment has high requirements for the power density, continuous operation, and transient stability of the whole machine, and there is a direct conflict between high power density design and substantial stability control in the power unit design. In order to meet the power density requirements of ultra-light power stations, three main problems need to be solved, namely engine speed oscillation and flameout in the process of load power mutation, matching of the generator and engine torque, and stabilizing the voltage waveform of the AC output end. In this paper, we proposed an exquisite control strategy for ultralight power generation systems in engines, generators, and inverters. The effectiveness and practicability of the proposed strategy are verified by both simulation and experiment. The results show that the proposed control strategy can effectively solve the instability problem of the ultralights generator set and improve the stability of the system, where the response recovery can be achieved within 0.9 seconds under the condition of total load increase or decrease, and the mismatching degree of the generator following the engine is reduced by 90%. The strategy could also guarantee long-term stable operation with high-quality electrical energy output.

Comparisons of power flows and efficiencies in two structurally quite similar cylindrical series-parallel planetary gear systems (PGSs) were performed in three separate parts of this paper. Each of these single degree of freedom (DoF) systems consists of three different 2KH subsystems connected in series-parallel. The main goal was to prove that apart from complex, structurally and dynamically coupled PGSs, there are also complex and only structurally coupled PGSs, in which the phenomenon of power flow circulation inside closed loops does not occur. Such a half-coupled type of PGS is herein called pseudo-coupled. Therefore, Part I discusses in detail the geometry, kinematics and statics of coupled PGSs in order to determine power flow paths. A comparison of the directions of power flow in both types of PGSs can be made in Part II after determining the power flow paths in the second planetary gear in a similar way. The directions of power flow in both types of PGSs were determined in a relatively simple way, thanks to the distinction between active and passive torques and thus active and passive shafts of individual subsystems. The efficiency comparison made in Part III will show whether power circulation has an influence on the efficiency value, at least in these two types of PGSs.

Keeping the bus voltage within acceptable limits depends on dispatching reactive power. Power quality improves as a result of creating an effective power flow system, which also helps to reduce power loss. Therefore, Optimal Reactive Power Dispatch (ORPD) studies aim at designing appropriate system configurations to enable a reliable operation of power systems. Establishment of such a configuration is handled through control variables in power systems. On the other hand, installing Distributed Generation Unit (DGU) into a power system can have an important effect on power quality and power loss minimization. In this paper, Grey Wolf Optimization (GWO method is applied to ORPD problem for the first time, to find optimal placement of newly installed DGUs at the power system. Active power loss and voltage minimization have been minimized by optimizing the control variables while keeping them within their upper and lower bounds, and by finding the optimal placement of a newly installed DGU in power system. On the basis of IEEE 30 bus and IEEE 118 bus systems, performance of the suggested approach is investigated. A comparison is also performed among the proposed method and some other methods. Test results demonstrate that the resulting configuration contributes to growing the rate of renewable integration to a power system. The results also indicate that the suggested optimization approach applied to ORPD problem has improved power system performance in terms of both on power loss and voltage deviation. The promising results highlight the potential of the GWO algorithm to facilitate the integration of renewable power sources, and its role in promoting sustainable energy solutions.

The environmental issues we are currently facing require long-term prospective efforts for sustainable growth. Renewable energy sources seem to be one of the most practical and efficient alternatives in this regard. Understanding a nation's pattern of energy use and renewable energy production is crucial for developing strategic plans. No previous study has been performed to explore the dynamics of power consumption with the change in renewable energy production on a country-wide scale. In contrast, a number of deep learning algorithms demonstrated acceptable performance while handling sequential data in the era of data-driven predictions. In this study, we developed a scheme to investigate and predict total power consumption and renewable energy production time series for eleven years of data using a Recurrent Neural Network (RNN). The dynamics of the interaction between the total annual power consumption and renewable energy production are investigated through extensive Exploratory Data Analysis (EDA) and a feature engineering framework. The performance of the model is found satisfactory through the comparison of the predicted data with the observed data, visualization of the distribution of the errors and Root Mean Squared Error (RMSE) value of 0.084. Higher performance is achieved through the increase in the number of epochs and hyperparameter tuning. The proposed framework can be used and transferred to investigate the trend of renewable energy production and power consumption and predict the future scenarios for different communities. Incorporation of the cloud-based platform into the proposed pipeline may lead to real-time forecasting.

Presently power control and management play a vigorous role in information technology and power management. Instead of non-renewable power manufacturing, renewable power manufacturing is preferred by every organization for controlling resource consumption, price reduction and efficient power management. Smart grid efficiently satisfies these requirements with the integration of machine learning algorithms. Machine learning algorithms are used in a smart grid for power requirement prediction, power distribution, failure identification etc. The proposed Random Forest-based smart grid system classifies the power grid into different zones like high and low power utilization. The power zones are divided into number of sub-zones and map to random forest branches. The sub-zone and branch mapping process used to identify the quantity of power utilized and the non-utilized in a zone. The non-utilized power quantity and location of power availabilities are identified and distributed the required quantity of power to the requester in a minimal response time and price. The priority power scheduling algorithm collect request from consumer and send the request to producer based on priority. The producer analysed the requester existing power utilization quantity and availability of power for scheduling the power distribution to the requester based on priority. The proposed Random Forest based sustainability and price optimization technique in smart grid experimental results are compared to existing machine learning techniques like SVM, KNN and NB. The proposed random forest-based identification technique identifies the exact location of the power availability, which takes minimal processing time and quick responses to the requestor. Additionally, the smart meter based smart grid technique identifies the faults in short time duration than the conventional energy management technique is also proven in the experimental results.

The work addresses the problem of Power Quality (PQ) metrics (or indexes) suitable for DC grids, encompassing Low and Medium Voltage applications, including electric transports, all-electric ships and aircrafts, electric vehicles, distributed generation and microgrids, modern data centers, etc. The two main pillars on which such PQ indexes are discussed and built are: i) the physical justification, so the electric phenomena affecting DC grids and components (PV panels, fuel cells, capacitors, batteries, etc.), causing e.g. stress of materials, ageing, distortion, grid instability; ii) the existing standardization framework, pointing out desirable coverage and extension, similarity with AC grids standards, but also inconsistencies. The first point is made more clear and usable by a graphical overview of the discussed phenomena. On this basis PQ is interpreted beyond the usual low-frequency range, including thus supraharmonics and common-mode disturbance, and filling the gap with the Electromagnetic Compatibility domain. However, phenomena typical of EMC and electrical safety (such as various types of overvoltages and fast transients) are excluded. Suitable PQ indexes are then reviewed, suggesting integrations and modifications, to cover the relevant phenomena and technological progress, and to better follow the normative exigencies.

The development of small scale hydroelectric power plants in Norway is determined by natural conditions, policies, attitudes and property rights. The owner of the river is the central decision maker. It is he who decides whether he will develop the power plant himself, Whether he wants to enter into a contract with an external investor and let him develop the power plant, whether he will sell his property rights or postpone the decisions. All available choices will involve risk. In order for him to make the best choice he must find the certainty equivalent to each of the choices and choose the one with the highest certainty equivalent. This is the first time the utility theory of John von Neumann and Oskar Morgenstern has been applied to decision makers in the hydro power industry in Norway.

The growing attention for plug-in electric vehicles, and the associated high-performance demands, have initiated a development trend towards highly efficient and compact on-board battery chargers. These isolated ac-dc converters are most commonly realized using two conversion stages, combining a non-isolated power factor correction (PFC) rectifier with an isolated dc-dc converter. This, however, involves two loss stages and a relatively high component count, limiting the achievable efficiency and power density and resulting in high costs. In this paper a single-stage converter approach is analyzed to realize a single-phase ac-dc converter, combining all functionalities into one conversion stage and thus enabling a cost-effective efficiency and power density increase. The converter topology consists of a quasi-lossless synchronous rectifier followed by an isolated dual active bridge (DAB) dc-dc converter, putting a small filter capacitor in between. To show the performance potential of this bidirectional, isolated ac-dc converter, a comprehensive design procedure and multi-objective optimization with respect to efficiency and power density is presented, using detailed loss and volume models. The models and procedures are verified by a 3.7 kW hardware demonstrator, interfacing a 400 V dc-bus with the single-phase 230 V, 50 Hz utility grid. Measurement results indicate a state-of-the-art efficiency of 96.1% and power density of 2.2 kW/dm³, confirming the competitiveness of the investigated single-stage DAB ac-dc converter.

One of the major sources of catastrophic failures and deterioration of the mechanical properties of metals such as ductility, toughness, and strength, of various engineering components during application is hydrogen embrittlement (HE). It occurs as a result of adsorption, diffusion, and interaction of hydrogen with various metal defects like dislocations, voids, grain boundaries and oxide/matrix interfaces due to its small atomic size. Over the years, extensive effort has been dedicated to understanding hydrogen embrittlement sources, effects, and mechanisms. This research aimed at assessing the tensile properties; toughness, ductility, and susceptibility to hydrogen embrittlement, of cold-finished mild steel. Steel coupons were subjected to electrochemical hydrogen charging in a carefully chosen alkaline solution over a particular time and at various charging current densities. Tensile property tests were conducted immediately post the charging process, and the results were compared with those of uncharged steel. The findings revealed a clear drop in toughness and ductility with increasing hydrogen content. Fracture surfaces were examined to determine failure mechanisms. This evaluation has enabled the prediction of the steel's ability to withstand environments with elevated hydrogen concentrations during practical applications.

The article delves into the crucial realm of compressing hydrogen in its gaseous state, a pivotal process for enhancing its viability in both civil and industrial sectors. The study initiates by providing a concise overview and comparison of diverse hydrogen storage methodologies, laying the groundwork with an in-depth analysis of hydrogen's thermophysical properties. It scrutinizes plausible configurations for hydrogen compression, aiming to strike a delicate balance between energy consumption, predominantly derived from the fuel itself, and the requisite number of compression stages. Notably, to render hydrogen storage competitive in terms of volume, pressures of at least 350 bar are deemed essential, albeit at an energy cost amounting to approximately 10% of the fuel's calorific value. Multi-stage compression emerges as a crucial strategy, not solely for energy efficiency, but also to curtail temperature rise, with an upper limit set at 200°C. This nuanced approach is underlined by the exploration of compression levels commonly cited in the literature, particularly 350 bar and 700 bar. Ultimately, the study advocates for a three-stage compression system as a pragmatic compromise, capable of achieving high-pressure solutions while keeping compression work below 10 MJ/kg, a threshold indicative of sustainable energy utilization.

A dioxomolybdenum catalyst [(MoO2Cl2-O-MoO2Cl2)(L)] (1) (with L (1S,2S)-N,N´-bis(2-pyridinecarboxamide)-1,2-cyclohexane) was prepared and used as catalyst for the desulfurization of a multicomponent model fuel containing the most refractory sulfur compounds in real fuels. This complex showed to have a high efficiency to oxidize the aromatic benzothiophene derivative compounds present in fuels, mainly using a biphasic 1:1 model fuel/MeOH system. This process conciliates catalytic oxidative and extractive desulfurization, occurring the oxidation of the sulfur compounds in the polar organic solvent. The oxidative catalytic performance of (1) showed to be influenced by the presence of water in the system. Using 50% aq. H2O2 it was possible to reuse the catalyst and the extraction solvent MeOH during ten consecutive cycles without loss of desulfurization efficiency.

The global warming has caused poor grape skin coloration and reduced the production of high-quality berries. To overcome these problems, the effect of synephrine (Syn) on anthocyanin accumulation was investigated. Syn treatment above 1 mM increased anthocyanin content in cultured grape cells in a molecular-structure-specific and concentration-dependent manner, and increased only the anthocyanin without affecting the sugar/acid ratio in grape bunches. It increased the expression of genes linked to anthocyanin synthesis after 24 h of treatment, without affecting phytohormone levels. Syn treatment induced the expression of SOD3, elevating hydrogen peroxide (H2O2) production from 3 to 24 h after treatment in cultured cells. Subsequent increases in CAT and APX6 expression occurred, which encode H2O2-eliminating enzymes. In cultured grape cells, Syn and H2O2 treatments upregulated the H2O2-responsive gene Chit4 and the anthocyanin-biosynthesis-related genes mybA1 and UFGT 4 days after the treatments and promoted anthocyanin accumulation 7 days after the treatments. In berries, both treatments enhanced anthocyanin accumulation after 9 days. These results suggest that Syn promotes anthocyanin accumulation through the production of H2O2 without the upregulation of phytohormone biosynthesis. Syn treatment is expected to improve poor grape coloration and contribute to higher-quality fruit production.

Fibroin-chitosan composites, especially those containing nanohydroxyapatite, show potential for bone tissue regeneration. The physicochemical properties of these biocomposites depend on the compatibility between their components. In this study, the intermolecular interactions of fibroin and chitosan were analyzed using a molecular dynamics approach. Two types of systems were investigated: one containing acetic acid and the other containing calcium (Ca²⁺) and hydrogen phosphate (HPO₄²⁻) ions mimicking hydroxyapatite conditions. After obtaining the optimal equilibrium structures, the distributions of several types of interactions including hydrogen bonds, ionic contacts, and hydrophobic contacts along with the structural and energetical features were examined. The calculated binding energy values for the fibroin-chitosan complexes confirm their remarkable stability. The high affinity of fibroin for chitosan can be explained by the formation of a dense network of interactions between considered biopolymers. These interactions were found to be primarily hydrogen bonds and ionic contacts involving ALA, ARG, ASN, ASP, GLN, GLU, GLY, LEU, PRO, SER, THR, TYR, and VAL residues. As it was established, the complexation of fibroin with chitosan maintains the β-sheet conformation of the peptide. β-Sheet fragments in fibroin are involved in the formation of significant amount of hydrogen bonds and ionic contacts with chitosan.

Hydrogen has a leading role in accomplishing a net zero green-house gas emission future. Today’s challenge is producing green hydrogen to cover the fuel demand of transportation and industry, to gain independence from fossil fuels. This review’s goal is to demonstrate critically the existing methods of biomass treatment and assess their ability to scale up. Biomass is an excellent hydrogen carrier and biomass-derived processes are the main target for hydrogen production as it is an innovative pathway to green hydrogen production. Comparing the existing processes, thermochemical treatment is found to be far more evolved than biological or electrochemical treatment especially with regard to scaling prospects.

Hydrogen fuel is gaining particular attention in internal combustion engines. In addition to zero-carbon emissions, major advantages relate to its combustion characteristics, which allow significant increase in thermal efficiency under ultra-lean operation and with very low NOx levels. The ignition system is one of the main technology enablers, as it determines the capability to control ultra-lean operations, avoid backfire phenomena, or reduce the risks of abnormal combustions. The latter results from the hydrogen low ignition energy and it is associated with factors like high-temperature residuals, hot spots, and irregular spark plug discharge. ACIS gen 2-Barrier Discharge Igniter excels in accelerating the initial flame growth speed by the generation of non-equilibrium low-temperature plasma, strong ignition promoter for the combined action of kinetic and thermal effects. Moreover, its volumetric discharge facilitates combustion initiation on a wide region, in contrast to the localized ignition of traditional spark systems. In this work we present for the first time, to the best of our knowledge, experimental results showing the performance of a hydrogen engine with a low-temperature plasma discharge. Tests were conducted on a single-cylinder research engine, achieving ultra-lean conditions with cycle-to-cycle variability results below 2.5%. The analysis indicates that the H2 - BDI combined solution is capable of accelerating the evolution of the flame front compared to traditional spark plugs, leading to a significant reduction in the cycle-to-cycle variability. A meticulous adjustment of the BDI control parameters further enhances igniter performance and contributes to a deeper understanding of the innovative approach proposed in this study.

Decarbonization of air mobility requires the decarbonization of its energy. While biofuels will play an important role, other low carbon energy carriers based on electricity are considered: battery electrification, liquid hydrogen (LH₂) or eFuel, a hydrogen-based energy carrier. Each energy carrier has its own conversion steps and losses and its own integration effects with the aircraft. These combinations lead to different energy requirements and must be understood to compare their cost and CO₂ emissions. Since they are all electricity-based, this study compares these energy carriers using the well to rotor methodology when applied to a standard Vertical Take-Off and Landing (VTOL) air mobility mission. This novel approach allows one to understand that the choice of the energy carrier dictates the propulsive system architecture, leading to integration effects with the aircraft which can significantly change the energy required, from 400 to 2665 kWh for the same mission. These deviations lead significant differences in CO₂ emissions and costs. Battery electrification is impacted by the battery manufacturing but has the lowest electricity consumption. It is an optimum solution but only until the battery weight can be lifted. In all scenarios eFuel is more efficient than LH₂. We conclude that carrying the most efficient molecule in an aircraft pays the extra energy cost spent on the ground. Finally, we found that for each of these energy carriers, it is the electricity carbon intensity and price which will dictate the cost and CO₂ emissions of an air mobility mission.

The study reports the effect of some metal carbides (niobium carbide, vanadium carbide, titanium carbide, and manganese sulfide) on hydrogen embrittlement in the pipeline industry using plane wave’s density functional theory (DFT). Our results predicted that the interaction of hydrogen molecules with these metals carbide occurs in the long range with binding energy varying in the energy window [0.70eV to 0.043eV]. Also, our study shows the desorption of H2 molecules from these metal carbides in the chemisorptions. Since, hydrogen embrittlement, occurs in the atomic state of hydrogen, therefore our finding in the atomic interaction of hydrogen with NbC, VC, TiC, and MnS showed that the strength of the trapping of the hydrogen atom could be classified as: TiC+H>VC+H>NbC+H> MnS+H. In addition, our study reveals that the carbon site is the most favorable hydrogen trapping site than the metal one. Furthermore, our results demonstrate that increasing the layer can also be an efficient way to enhance the trapping capacity.

In the last decade, with the increased concerns about the global environmental situation, attempts have been made to promote the replacement of fossil fuels with sustainable sources. For transport, which accounts for around a quarter of total greenhouse gas emissions, meeting climate neutrality goals will require replacing existing fleets with electric or hydrogen propelled vehicles. This research addresses the problem of transport fleet renewal by proposing a multi-criteria decision-making approach, taking into account the multiple propulsion technologies currently available and the objectives of the EU Green Deal, as well as the uncertainty related to the technological scenario, in a generalized Life Cycle framework. The proposed approach, based on the TOPSIS model, demonstrates how the optimality of the choice is related to the different technological scenarios and to the risky attitude of the decision maker. The proposed methodology is finally validated against a practical case referred the strategic fleet renewal decision process, and the results obtained demonstrate how the decision maker’s perception about the technological evolution of the propulsion technologies influences the decision process, thus leading to different optimal choices.

Amylin, also known as islet amyloid polypeptide (IAPP), is a metabolic homeostasis-related hormone that is produced and released by the β cells of the pancreas, the same cells that produce insulin. Insulin-degrading enzyme (IDE) is a protease enzyme that plays an essential role in the breakdown and degradation of various peptides, including insulin and amylin. Direct binding & interaction between amylin and IDE is inextricably linked to the degradation of amylin, and research and development effort in this area is crucial to understand the potential therapeutic implications of disrupting the IDE-amylin interaction in the context of conditions where metabolic homeostasis needs to be regulated, such as diabetes and obesity. Here, this article incorporates currently available experimental complex structure of amylin and IDE, and delves deep into the interstructural biophysics underlying the binding interface of the two interacting partners. With a set of comprehensive structural biophysical analysis, this article identified an intriguing region of high electrostatic potential indicative of strong binding sites between the first N-terminal lysine (Lys1, K1) residue of amylin and Glu341 (E341) of IDE. This unique electrostatic hotspot presented herein paves the way for the rational design of drug-like small molecules that can selectively disrupt this interaction, offering a targeted therapeutic strategy for improved metabolic homeostasis, particularly for patients with diabetes and obesity.

Our analysis of previous studies shows that solar energy and wind can consume negligible amount of water to generate one megawatt of electricity.

The processes of hydrogen reduction of silicon and germanium chlorides under the conditions of high-frequency (40.68 MHz) counteracted arc discharge stabilized between two rod electrodes are investigated. The main gas-phase and solid products of plasma-chemical transformations are determined. Thermodynamic analysis of SiCl4 + H2 and GeCl4 + H2 systems for optimal process parameters was carried out. Using the example of hydrogen reduction of SiCl4 by the method of numerical modeling, gas-dynamic and thermal processes for this type of discharge are investigated. The impurity composition of gas-phase and solid reaction products is investigated. The possibility of single-stage production of high-purity Si and Ge mainly in the form of compact ingots, as well as high-purity chlorosilanes and trichlorogermane, is shown.

Two-dimensional (2D) transition metal dichalcogenides (TMDCs) nanosheets have shown extensive applications due to their excellent physical and chemical properties. However, the low light absorption efficiency limits their application in optoelectronics. By rolling up 2D TMDCs nanosheets, the one-dimensional (1D) TMDCs nanoscrolls are formed with spiral tubular structure, tunable interlayer spacing and opening ends. Due to their increased thickness of scroll structure, the light absorption is enhanced. Meanwhile, the rapid electron transportation is confined along the 1D structure. Therefore, the TMDCs nanoscrolls show improved optoelectronic performance compared to 2D nanosheets. In addition, the high specific surface area and active edge site from bending strain of basal plane make them promising materials for catalytic reaction. Thus, the TMDCs nanoscrolls have attracted intensive attention in recent years. In this review, the structure of TMDCs nanoscrolls is firstly demonstrated and followed by various preparation methods of the TMDCs nanoscrolls. Afterwards, the applications of TMDCs nanoscrolls in the fields of photodetection, hydrogen evolution reaction, and gas sensing are discussed.

Hydrogen is believed to be the principal domain of sustainable energy drive as an alternative to fossil fuels. Unlike the existing standards and knowledge for other fuels, the integrity of sealing and storage materials under the hydrogen environment is not comprehensively studied due to the comparatively new technology and lack of standard laboratory protocols. Typically, storage and polymer materials used as sealing experience degradation and damage in different ways over time in the exposure of hydrogen at different operating conditions, called aging. Improved understanding of the physical and chemical mechanism of degradation due to gaseous hydrogen atmosphere; helps to select and develop the materials best suited to carrier and sealing for respective applications. Damage to materials from aging is inevitable in high-pressure hydrogen gas exposure. This review discusses the mechanism of different categories of aging of storage and sealing materials under the hydrogen environment. Also, the article approaches discussing different laboratory test methods for each type of aging simulation. It covers the limitation of current research on determining material integrity through existing techniques of aging experiments and also explores the latest development. Important improvements are suggested in terms of materials development and testing procedures to meet the existing knowledge in the literature.

The saphenous vein is the conduit of choice for bypass grafting. Unfortunately, the hemodynamic stress associated with the arterial environment of the bypass vein graft leads to the development of intimal hyperplasia (IH), an excessive cellular growth and collagen deposition that results in restenosis and secondary graft occlusion. Hydrogen sulfide (H2S) is a ubiquitous redox-modifying gasotransmitter that inhibits IH. H2S is produced via the reverse trans-sulfuration pathway by 3 enzymes: cystathionine γ-lyase (CSE), cystathionine β-synthase (CBS), and 3-mercaptopyruvate sulfurtransferase (3-MST). However, the expression and regulation of these enzymes in the human vasculature remains unclear. Here, we investigated the expression of CSE, CBS and 3-MST in segments of native human saphenous vein and large arteries. Furthermore, we evaluated the regulation of these enzymes in vein segments cultured under static, venous (7 mmHg pressure) or arterial (100 mmHg pressure) pressure. CSE was expressed in the media, neointima and intima of the vessels and was negatively regulated by arterial shear stress. Adenoviral-mediated CSE overexpression or RNA interference-mediated CSE knock-down revealed that CSE inhibited primary human VSMC migration but not proliferation. We propose that high shear stress in arteriovenous bypass grafts inhibits CSE expression in both the media and endothelium, which may contribute to increased VSMC migration in the context of IH.

The synthesis and crystal structure of pyrazine-2,5-diyldimethanol (pzydmH2, C8H8N2O2) a new symmetric water-soluble N,O-chelating tetra-dentate organic ligand is reported and an environmentally friendly method was used to synthesize coordination compounds in water under ambient conditions from the reaction of pzydmH2 with the halide salts of Cu(II), Zn(II), Hg(II) and Cd(II): {[Cu(pzydmH2)0.5(µ-Br)(Br)(H2O)]·H2O}n 1, {[Zn2(pzydmH2)(µ-Cl)(Cl)3(H2O)]·H2O}n 2, [Hg2(pzydmH2)0.5(µ-Cl)2(Cl)2]n 3, {[Cd2(pzydmH2)(µ-Cl)4]·H2O}n 4, and {[Cd2(pzydmH2)(µ-Br)4]·H2O}n 5. Single-crystal X-ray diffraction analysis revealed that 1-3 are 1D coordination polymers and 4 and 5 are 3D coordination networks, all constructed by bridging pyrazine-2,5-diyldimethanol and halogen ions. The hydroxyl groups in the organic linker extend the 1D chains to non-covalent 3D networks. In all non-covalent and covalent 3D networks water molecules were trapped by strong hydrogen bond interactions. Supramolecular analysis revealed strong O-H···O, O-H···N, O-H···X and week of C-H···O, C-H···X (X = Cl, Br) hydrogen bonds, as well as π-π(pyrazine ring), metal-halogen···π(pyrazine ring) and O-H···ring(5-membered chelate ring) interactions. Also X···O weak halogen bonds are present in 1-5 (X = Cl and Br).

The aim of this study was to examine whether H2O2, generated in such beverages as tea and coffee, is formed also in infusions of medicinal herbs and propose the possible mechanism of its formation. Infusions of sixteen herbs were studied and the presence of H2O2 was found in all cases. The highest concentrations of H2O2, exceeding 50 µM, were found in the infusions of leaves of Betula and Polygonum, and of the inflorescence of Tilia. These low amounts of H2O2 should not have a harmful effect and may even exert beneficial action, perhaps contributing to the health effects of the herbs. Generation of semiquinone and superoxide radicals was detected in herbal infusions, indicating that oxidation of phenolic compounds is the main source of H2O2 in these infusions. Herbal infusions were cytotoxic to human ovary cancer SKOV-3 and PEO1 cells; this cytotoxicity was compromised by catalase added to the growth medium, demonstrating the contribution of hydrogen peroxide to the cytotoxic action of herbal extracts.