A new type of low cost, environmentally friendly wood-plastic composites (WPC) containing carbon nanotubes(CNT)of low content 0%, 0.05wt%, 0.1wt% and 0.15wt%, wood fibers of 14wt% and polymer PES of 86wt% was manufactured by the selective laser sintering (SLS) approach of 3D printing. The experimental results showed that the incorporating of CNTs could obviously increase the mechanical properties of the wood/PES composites material. The tensile strength, bending strength and elasticity modulus were 76.3%, 227.9% and 128.7% higher with 0.1wt% CNTs than without CNTs. And the mechanical properties of specimens firstly increased and then decreased with the increasing contents of CNTs. The SEM results of the specimens’ fracture morphology indicated that the preferable bonding interfaces between wood flour grains and PES grains were achieved by adding CNTs to the composites. There are two reasons to explain why the composites possessed the superior mechanical properties: CNTs could facilitate the laser sintering process of wood plastic composites due to their thermal conductivities; also, CNTs could directly reinforce the WPC composites as reinforcement.

Concrete contributes 8% of all global carbon emissions making the need to find substitute critical for environmental sustainability. Research has indicated the potential for recycled plastics to be used as concrete substitutes. This study extends existing research by investigating the use of polycarbonate (PC) in plastic sand bricks as a mechanical equivalent to concrete. PC has high compressive strength, durability, impact strength, thermal resistivity, clarity, fatigue resistance, and UV resistance. This work provides a method and mold to produce a matrix of sand-plastic sample compositions with dimensions adhering to ASTM D695 standard for compressive properties of rigid-plastic. Compositions of 0% (control), 20%, 30%, 40%, and 50% sand by weight were tested. Samples were tested for compressive strength until yield and stress-strain behaviors plotted. The results for 100% PC demonstrated an average and maximum compressive strength of 71 MPa and 72 MPa, respectively. The 50% PC and 50% sand composition yielded an average and maximum compressive strength of 71 MPa and 73 MPa respectively with an increase in compressive stiffness, and transition to shear failure resembling cement. With a composite density of 1.86 g/cm3 against concrete’s average 2.4 g/cm3, and a compressive strength exceeding commercial concrete demands of 23.3 MPa to 30.2 MPa, this lightweight alternative meets the strength demands of concrete, reduces the need for new construction materials, and provides an additional recycling opportunity for nonbiodegradable waste plastic.

PVC-based materials are bad in terms of biodegradability. To enhance the ecological property of such materials, the fabrication of PVC-based composites using biofillers with acceptable performance characteristics could be considered. In this work, plant-filled PVC-based composite materials were obtained and study their optical, structural, thermal, and mechanical properties depending on the nature of the filler (spruce flour, birch flour, and rice husk) were studied. Increasing the proportion of plant filler somewhat reduces the strength characteristics and reduces the flexibility of the samples. But samples with plant filler allows them to be used at low temperatures without changing the operating characteristics. Some of the fillers affected the thermal stability of composites by increasing their thermal decomposition resistance. So, results have shown that plant-filled polymer composites based on PVC can be used on an equal basis with unfilled PVC plastic compound for some applications such as construction.

Keywords: Wood residuals; Forest biomass; Wood composite; Wood floor; Life Cycle Assessment.

The microbial colonisers of plastics – the ‘plastisphere’ – can affect all interactions that plastics have with their surrounding environments. While only specifically characterised within the last 10 years, at the beginning of 2021 there were 140 primary research and 65 review articles that investigate at least one aspect of the plastisphere. We gathered information on the locations and methodologies used by each of the primary research articles, highlighting several aspects of plastisphere research that remain understudied: (i) the non-bacterial plastisphere constituents; (ii) the mechanisms used to degrade plastics by marine isolates or communities; (iii) the capacity for plastisphere members to be pathogenic or carry antimicrobial resistance genes; and (iv) meta-OMIC characterisations of the plastisphere. We have also summarised the topics covered by the existing plastisphere review articles, identifying areas that have received less attention to date – most of which are in line with the areas that have fewer primary research articles. Therefore, in addition to providing an overview of some fundamental topics such as biodegradation and community assembly, we discuss the importance of eukaryotes in shaping the plastisphere, potential pathogens carried by plastics and the impact of the plastisphere on plastic transport and biogeochemical cycling. Finally, we summarise the future directions suggested by the reviews that we have evaluated and suggest other key research questions.

Bending of solid wood from European oak is one of the most demanding technological processes due to its specific structural and physical properties and variability. We investigated the influence of wood moisture content (MC) and stiffness, determined by NDT, as well as previous drying methods on the bending ability of the wood. The best quality was obtained with bending specimens bent at a moisture content of at least 16 % and quarter or semi-quartersawn. The number of rejected specimens increased slightly when HF bending was used. Single-stage predrying of oak to a final MC of 8 % resulted in a high rejection rate (> 70 %) regardless of drying technique. The acceptance rate was higher for less stiff specimens where the ratio of ultrasonic velocity in the straight (vS) and bent region (vB) was less than 0.5 (vB/vS).

Fast-growing teak is widely cultivated in Indonesia to address the supply and demand of teak trees. However, efforts still need to be made to evaluate the condition of standing teak trees during their growth period. Studies on nondestructive testing (NDT) of wood based on electrical properties through dielectric spectroscopy (DS) are recently being developed, especially for standing tree evaluation. The study aimed to analyze the dielectric value of a fast-growing standing teak tree at frequency ranges 250 kHz – 60 MHz and to understand the relationships between physical and anatomical properties. Dielectric spectroscopy data were collected directly on the trees 4, 5, and 7 years old using a capacitance measurement system. Meanwhile, physical and anatomical samples were taken using a Ø 0.5 cm increment borer. The results showed that fiber length (FL), lumen diameter (LD), and fiber wall thickness (FWT) were significantly different at each tree age. This research found the optimal dielectric frequency to discriminate the wood properties in standing trees. There is a weak relationship (R= 0.2) in predicting the anatomical wood properties, while moderate to strong relationships (R= 0.4 to R= 0.8) are found in predicting wood density based on the selected frequency and moisture content variables. Further analyses and data processing can be improved by finding significant variables in the capacitance measurement system.

Deadwood represents a source of nutrients, carbon and water for metabolism within forest ecosystem. Nutrients are mobilized due to the decomposition of wood, which is a long-term process that can be best studied by analysing environmental data on a temporary scale. Our study provides physico-temporal data on the downed logs of three major tree species in European temperate forests: Abies alba Mill., Fagus sylvatica L. and Picea abies (L.) Karst. Time since death was obtained using tree censuses (repeated for 40 years) and dendrochronology for each single downed log, the oldest being 75 years old. Standard laboratory methods were used for the determination of wood density and moisture changes. F. sylvatica was decomposed rapidly in the initial phase – mass loss was 50% during the 5 years after death, while A. alba and P. abies lost 13% and 16%, respectively. Downed logs of F. sylvatica contained 391 kg of water per m³, while these of P. abies 279 kg. A log-transformed linear model was created that shows the dependence of time since death on mass loss. According to the model, F. sylvatica had the shortest total decomposition time (39 years), followed by A. alba (58 years) and P. abies (86 years).

Bent trees have been observed during the early years in juvenile plantations (less than 5 years-old) of Tectona grandis in Costa Rica. The relationship between bending and the morphological characteristics of the trees was explored. An evaluation of bent trees was conducted in six juvenile plantations (8, 17, 27, 28, 31, and 54 months old) of Tectona grandis. Site 1 with 8-month-old plantations did not display any relationship with any tree morphological variable (diameter, height, and crown weight of tree), whereas for the sites 2, 3, and 4 with 17-, 27-, and 28-month-old plantations, respectively, all the tree morphological variables were statistically correlated with the bent trees. A multiple regression analysis showed that the most influential variables were height to crown base, crown weight, diameter, and total height of the tree. An evaluation of the bending risk factor (RF) was correlated with the height to crown base, crown weight, and form factor. The modulus of elasticity and chemical compositions of bent trees differed from those of straight trees. The causes of tree bending are complex, involving, among other factors, the morphology of the trees, plantation conditions, and other factors specific to the xylem, such as the specific gravity, modulus of elasticity, and presence of calcium and magnesium in the wood.

Plastic poses a significant threat to the environment, polluting land, water, and air. It is a broad term encompassing a variety of polymers. In the form of microplastics and nanoplastics, it can induce toxicity in water bodies. Plastic debris not only physically pollutes freshwater, but also chemically, undergoing changes over time due to hydroclimatic effects. Rivers serve as conduits, transporting plastics from minor tributaries to major rivers and ultimately into the ocean, endangering marine life. India, as a developing country with the largest population and numerous rivers, generates a significant amount of plastic waste, a substantial portion of which finds its way into rivers, leading to alarming rates of plastic accumulation in the ocean. Previously, policymakers focused primarily on landfills for plastic waste, neglecting the pollution of water bodies. The consequences of this neglect are evident, with major rivers in the country severely affected by plastic waste, necessitating advanced, efficient, and sustainable solutions. This study aims to establish a comprehensive framework for managing plastic waste, understanding its transport mechanisms to the ocean, and recognizing the threats it poses to life. It also expounds on harmful plastic pollutants in water, globally adopted technologies, and emphasizes the need for further research and data collection in this field. The primary concluding point is to prevent plastics from entering waterways and to actively collect river and marine plastic pollution. Banning single-use plastics and implementing efficient collection methods are crucial in containing plastic pollution. Effluents from industries should not be overlooked, as they often contain harmful micro and nanoplastics with ecotoxicological effects. The innovative concept of the "4Rs" - Refuse, Reduce, Reuse, and Recycle - stands as the cornerstone for safeguarding the environment against plastic pollution.

Fossil-based plastics are significant contributors to global warming through CO₂ emissions. For more sustainable alternatives to be successful, it is important to ensure that consumers become aware of the benefits of innovations such as bio-based plastics, in order to create demand and a willingness to initially pay more. Given that consumer attitudes and (inaccurate) beliefs can influence the uptake such new technologies, we investigated participants’ attitudes towards fossil-based and bio-based plastic, their perceived importance of recycling both types of plastic, their willingness to pay, and their perceptions of bio-based plastic in four studies (total N = 961). The pre-registered fourth study experimentally manipulated information about bio-based plastic and measured willingness to pay for different types of plastic. The results suggest participants hold very favourable attitudes and are willing to pay more for bio-based products. However, they also harbour misconceptions, especially overestimating bio-based plastic’s biodegradability, and they find it less important to recycle bio-based than fossil-based plastic. Study 4 provided evidence that educating consumers about the properties of bio-based plastic can dispel misconceptions, retain a favourable attitude and a high willingness to pay. We found mixed evidence for the effect of attitudes on willingness to pay, suggesting other psychological factors may also play a role. We discuss how attitudes and misconceptions affect the uptake of new sustainable technologies such as bio-based plastics and consumers’ willingness to purchase them.

Tree decline resulting from climate change results in physiological weaknesses, attack by harmful pests and pathogen, and threatens forest ecosystem stability. In the work described here, the effects of drought on wood density, tree ring width, and variations in vessel morphology were investigated in Persian oak (Quercus brantii) in the forests of the Zagros Mountains, Ilam province, western Iran. Radial discs were cut from trunks of declined and healthy trees and wood blocks cut radially from the sapwood, heartwood, and juvenile core. Observations were made on transverse sections from the blocks using microscopy. In trees with decline symptoms, wood density was greater than the healthy trees. Furthermore, declining trees had the narrowest ring width, reduced vessel diameter, vessel area, and highest number of vessels and tylose in pith towards bark. It was concluded that changes in anatomical features are associated with the weakening of the trees and are components in declining tree health.

Wood is very susceptible to the action of biotic agents. There is a growing interest in the protection of wood and wood artworks to extend their life, using environmentally friendly preservatives. The aim of this paper was the study of nano/siliconate impregnation system for wood protection to control biological colonization. The biotic agents studied have been wood decay fungi. In conclusion, this paper has shown that all the treatments have presented an excellent protective performance against biotic agents. Is important to mention that a synergistic effect can be observed when generating the siliconate/nanoparticle mixtures, resulting in protective systems with excellent efficiency for all the degrading agents. Moreover, it presents an easy application, which represents not only a watertight protective system, but also a set of systems that may be used and managed according to the availability of the active components, the costs, and, most importantly, without having to modify the form of application.

The distribution of Mexican Magnolia species´ occur under restricted climatic conditions. As many other tree species from the tropical montane cloud forests (TMCF), Magnolia species appear to be sensitive to drought. Through the use of dendrochronological techniques, this study aims to determine the climate influence on the vessel traits of M. vovidesii and M. schiedeana which are endangered tree species that are endemic to the Sierra Madre Oriental in eastern Mexico. Because most of the tree species in TMCFs are sensitive to climate fluctuations, it is necessary to investigate the differences in the climatic adaptability of the vessel architecture of these trees. This could allow us to further understand the potential peril of climate change on TMCFs. We compared vessel frequency, length and diameter in drought and non–drought years in two Mexican Magnolia species. We used tree–rings width and vessel traits to assess the drought effects on Magnolias’ diffuse–porous wood back to the year 1929. We obtained independent chronologies for M. vovidesii with a span of 75 years (1941–2016), while for M. schiedeana we obtained a span of 319 years (1697–2016). We found that temperature and precipitation are strongly associated with differences in tree–ring width (TRW) between drought and non–drought years. Our results showed anatomical differences in vessel trait response between these two Magnolia species to climatic variation. We suggest that our approach of combining dendroclimatic and anatomical techniques is a powerful tool to analyse anatomic wood plasticity to climatic variation in Magnolia species.

Despite good intentions, the increasing number of plastic bag bans aimed at alleviating marine plastic pollution saw a correlated increase in the number of unintended consequences that emerged alongside the bans, suggesting that human behavior towards plastic bag consumption have not changed, but merely shifted, and are feeding into other major international environmental catastrophes. Nudge theory, which helps people make better choices for themselves without inhibiting their free will, is a potential solution that has been shown to play a subtle but important role in providing options under circumstances where complex information needs to be streamlined for the wider community, avoiding any unintended consequences and behavioural shifts that might arise from instruments that diminishes autonomy. It is therefore timely to look into the insights of nudge theory to encourage a positive behavioural change to reduce plastic bag consumption. Here we apply a systematic literature review to show how successful applications of nudges in supermarkets can be leveraged to reduce plastic bag consumption. We find that the current applications of nudges in various industries worldwide, including supermarkets have produced positive and encouraging results, as well as producing lasting behavioural change among the wider community. Supermarkets are identified as a powerful deployment site of these nudges due to their positioning as a dominant provider of plastic bags to the wider community, as well as being the largest and leading provider of daily food needs. Finally, we synthesise our findings to produce a coherent and testable framework of actionable interventions that supermarkets can employ to nudge customers towards reduced plastic bag reliance, accompanied with a visual timeline of a customer shopping in a supermarket experiencing these nudges.

Abstract: The ongoing use of plastic polymers to manufacture food packaging has raised concerns about the presence of nano- and microplastics (NMPs) in a variety of foods. This review provides the most recent data on NMPs' migration from plastic packaging into milk and dairy products. Also discussed are the possible effects of NMPs on nutrient digestion, absorption, and metabolism. Different kinds of milk products, including skimmed or whole liquid and powder milk, infant formula milk, and other dairy products, have been found to contain NMPs of various sizes, shapes, and concentrations. NMPs may interact with proteins, carbohydrates, and fats and have a detrimental impact on how well these nutrients are digested and absorbed by the body. The presence of NMPs in the gastrointestinal tract may impact how lipids, proteins, glucose, iron, and energy are metabolised, increasing the risk of developing health conditions such as diabetes, cardiovascular disease, hypertension, and some cancers. In addition to NMP, plastic oligomers released from food packaging material have been found to migrate to various food simulants and milk, though their effect on human health has yet to be investigated. Viewpoints on potential directions for future studies on NMPs and nutrient digestion, absorption, and health are also presented in this review.

This letter attempts to clarify an issue regarding the proper definition of plastic dislocation density tensor. This study shows that the Ortiz’s and Berdichevsky’s plastic dislocation density tensor are equivalent with each other, but not with Kondo’s one. To fix the problem, we propose a modified version of Kondo’s plastic dislocation density tensor.

Microplastics and nanoplastics (MP/NPs) have been found everywhere they have been searched. On the top of Everest, in the Mariana Trench, on the clouds e recently, microplastics have been discovered in the human placenta, meconium and babies’ feces. In this review we explain what the consequences of the presence of these pollutants in fetuses and newborns are, with particular attention to human breastfeeding. Finally, we outline the possible political and social solutions to the problem of plastic overproduction that characterizes the modern world.

The paper presents a conceptual model of the route of macroplastic debris (5 > mm) through a fluvial system, which can support future works on the overlooked processes of macroplastic storage and remobilization in rivers. We divided the macroplastic route into (1) input, (2) transport, (3) storage, (4) remobilization and (5) output phases. Phase 1 is mainly controlled by humans, phases 2–4 by fluvial processes, and phase 5 by both types of controls. We hypothesize that natural characteristics of fluvial systems and their modification by dam reservoirs and flood embankments construction are key controls on macroplastic storage and remobilization in rivers. The zone of macroplastic storage can be defined as a river floodplain inundated since the beginning of widespread disposal of plastic waste to the environment in the 1960s and remobilization zone as a part of the storage zone influenced by floodwaters and bank erosion. The amount of macroplastic in both zones can be estimated using data on the abundance of surface- and subsurface-stored macroplastic and the lateral and vertical extent of the zones. Our model creates the framework for estimation of how much plastic has accumulated in rivers and will be present in future riverscapes.

Understanding maturation stress and wood properties of poplar tension wood are critical for improving lumber yields and utilization ratio. In this study, Released Longitudinal Maturation Strains (RLMS), anatomical features, physical and mechanical properties, and nano-mechanical properties of the cell wall were analyzed at different peripheral positions and heights in nine inclined, 12-year-old poplar (Populus×euramericana ‘Zhonglin46’) trees. The correlations between RLMS and wood properties were determined. The results showed that there were mixed effects of artificial inclination on wood quality and properties. The upper sides of inclined stems had higher RLMS, proportion of G-layer, bending modulus of elasticity, and elastic modulus of cell wall but lower microfibril angle than the lower sides. At heights between 0.7 m and 2.2 m, only the double wall thickness increased with height, RLMS and other wood properties such as fiber length and basic density fluctuated or changed little with height. RLMS was a good indicator of wood properties in the tension wood area and at heights between 0.7 m and 1.5 m. The results of this study present opportunities to identify and select better quality wood in poplar trees.

Water management and soil pollution are hot issues in modern agriculture. While more production of food is required, this quantity has to be obtained using the minimum level of resources and the maximum amortization of assets. Moreover, studies show that in Europe, 30% of water consumption is for agriculture, which has a strong influence not only on the amount of water consumed, but also on its quality due to pollution caused by chemical fertilizers, pesticides and other pollutants used in this sector. Therefore, a major concern is related to the use of water, its efficient consumption, which requires optimal irrigation systems both in terms of water transport and distribution. In this context, but also in the context of a turbid environmental debate, the most important facts in agriculture are the protection of the environment on a long range of time. In order to obtain good results for an irrigation system, in this paper we will present a model for calculating the best suited material for a given geographical area and the optimal water content for irrigation

Lignocellulosic biomass, an abundant and renewable resource, serves as a crucial raw material for the production of biofuels, biochemicals, and various value-added products. This paper aims to develop and optimize a mild alkaline treatment of sawdust assisted by ultrasound, along with enzymatic hydrolysis of the pretreated material. The sonochemical pretreatment with alkali emerged as the optimal approach to enhance the susceptibility of cellulose to subsequent enzymatic hydrolysis, thereby increasing the yield of reducing sugars. A comparative study was performed using various ultrasonic applicators (horn and bath) and conventional assisted alkaline pretreatment. The ultrasonic assisted pretreatment revealed a higher delignification as 68% (horn) and 57% (bath) comparing with conventional pretreatment. Processes were optimized using a statistical analysis based on a 23 factorial design. The ratio between sawdust and alkanine solution (RSL = 0.5–1.5 g/100 mL), US amplitude (A = 20–60%), and working temperature (t = 30–50 °C) were selected as process factors. The optimal operating conditions to maximize the reducing sugar yield (138.15 mg GE /gsubstrate) were found as following: solid/liquid ratio RSL,opt = 1.25 g/100 mL, US amplitude Aopt = 60%, and and pretreatment temperature topt = 50 °C. The overall outcomes clearly confirmed the intensification of delignification by ultrasound assisted alkaline pretreatment

In Nigeria, the adoption of sustainable biomass for energy generation is on the rise. One crucial factor that affects the efficiency of Biomass utilization is the moisture content. This study investigates the economic impact of moisture at different stages of the wood biomass distribution chain, considering the entire chain. The methodology employed includes a comprehensive literature review, interviews, and economic calculations. By analyzing these factors, this research aims to provide valuable insights into the economics of moisture in wood biomass, contributing to the sustainable development of the Biomass energy sector in Nigeria. Based on the outcomes of this investigation, it has been discovered that the costs associated with moisture content in Nigeria amount to approximately ₦500,000,00 (Five Hundred Thousand Naira only). Utilizing wood Biomass with a moisture content of 32% weight, as opposed to 18% weight, has proven to be more costly. Transportation contributes to a significant portion of this increase, while the reduction in burning efficiency accounts for the remaining half. To further elaborate on these findings, it is crucial to understand that the transportation costs are impacted by the additional weight and volume of biomass with higher moisture content. This necessitates the use of more fuel and resources during transportation, resulting in increased expenses. Additionally, the decreased burning efficiency associated with higher moisture content poses a challenge. It leads to reduced energy output and increased fuel consumption, ultimately impacting the overall economic viability of wood biomass as an energy source. By identifying these factors, this study aims to provide insights into the economic implications of moisture content in the wood biomass distribution chain in Nigeria. These findings can serve as a basis for developing strategies to optimize the use of biomass, reduce costs, and enhance the sustainability of the energy generation process. One of the most convenient and cost-effective solutions to reduce transportation expenses and improve combustion efficiency is through planned air drying of wood biomass. Large-scale power plants typically prefer utilizing wood biomass that has undergone air drying, resulting in a moisture content ranging from 18% to 36% by weight. By implementing planned air-drying techniques, the moisture content of wood biomass can be significantly reduced, thereby decreasing transportation costs. As the biomass becomes lighter and less bulky, transportation requirements are optimized, leading to enhanced efficiency and reduced expenses. Moreover, air-dried wood biomass offers improved combustion characteristics. The reduced moisture content allows for better heat transfer during the combustion process, resulting in higher energy output and increased fuel efficiency. This not only improves the overall economics of utilizing wood biomass but also contributes to a more sustainable and environmentally friendly energy generation system. The application of planned air drying in the wood biomass distribution chain in Nigeria can serve as a practical solution to address the economic challenges associated with moisture content. By adopting this approach, stakeholders can maximize the potential of wood biomass as a renewable energy resource while minimizing costs and promoting sustainable practices.

This study investigated the presence and characteristics of Juglans neotropica in three ecosystems in Southern Ecuador: Montane Evergreen Forest, Evergreen Seasonal Lower Montane Forest, and Semideciduous Foot Montane Forest. The main focus was on the species' multipurpose nature as both a fruit and timber source. Six study sites, totaling at least 0.5 hectares each, were established, with four in Loja province and two in Zamora Chinchipe province.The results showed significant differences in dendrometric variables across the sites, with the most favorable growth recorded in The Tundo, where trees exhibited an average diameter at breast height (DBH) of 45.16 cm, basal area (G) of 1.41 m2, total height (TH) of 19.22 m, canopy height (CH) of 13 m, cubic volume (CV) of 3.55 m3, and total volume (TV) of 5.22 m3. The species displayed a clumped distribution pattern, as indicated by a Morisita index greater than 1. Regarding abundance, the highest density of 297 trees per hectare was found in Argelia, while Victoria had the lowest density of 46 trees per hectare. This research highlights the importance of Juglans neotropica as a multipurpose species, providing both valuable fruits and wood resources in the studied ecosystems of Southern Ecuador.

The study was carried out in zone 7 of Ecuador, in ecosystems of the Southern Montane Evergreen Forest of the Eastern Cordillera of the Andes that goes from 2200 to 3000 masl. In the Evergreen Seasonal Lower Montane Forest of Catamayo-Alamor, which ranges from 1600-2000 meters above sea level and finally in the Semideciduous Foot Montane Forest of Catamayo-Alamor, which ranges from 400-1600 meters above sea level. The objective was to know the occurrence, structure and abundance of J. neotropica. The investigation consisted of collecting secondary information on the occurrence of the species, to later verify it in situ. Six sites with areas ≥ 0.5 hectares were identified, four in the province of Loja and two in the province of Zamora Chinchipe. Regarding the structure, it was determined that there are significant statistical differences as well as in the dasometric variables between one site and another, presenting better growths El Tundo with average values in DAP(cm)= 45.16; G(m2) = 1.41; HT(m)= 19.22; HC(m)= 13; VC(m3) = 3.55; VT(m3) = 5.22. Regarding the Morisita index, the species presents adistribution pattern >1. Regarding abundance, it was determined that Algeria presented a maximum of 297 (ind/ha), and La Victoria 46 (ind/ha) with a minimum.

This work presents the results of three connection types in double-shear with dowel fasteners, using the simplified equations from the Eurocode 5. All design parameters were established and compared using three different wood strength and density properties, which constitute the members connections. Eighty-one connections were obtained, allowing to conclude about the number of fasteners needed to the applied tensile load. An increase in the number of dowels was obtained with the increased applied tensile load, lower dowel diameter, lower wood density, and lower strength material in all connection types in the study. The design characteristic load-carrying capacity per shear plane and fastener also decrease with the previously considered parameters.

To examine the hydrophobicity of torrefied wood fuel, the water resistances of torrefied pellets prepared by two different methods were evaluated using exposure tests under indoor and outdoor conditions. Torrefied pellets from the xylem of Japanese cedar (Sugi, Cryptomeria japonica) and oak (Konara, Quercus serrata) were prepared by two methods: the torrefaction of wood chips followed by pelletization and the pelletization of wood chips followed by torrefaction. It was found that the pellets prepared by pelletization followed by torrefaction had much lower moisture levels than those prepared by the other method and they showed almost no change in diameter after an outdoor weathering test. These characteristics are unique and indicate that the pellets can be applied not only for industrial use but also for residential and commercial purposes.

The rapid development in industries manufacturing plastic bags is taking serious consideration to save the environment and human health, one way or the other. This study examines the composition of degradable and non-degradable plastic bags collected from the markets of different sectors of Islamabad. Hundred samples of both Degradable and non-degradable plastic bags were collected from the open market. The concentrations, proportion, and patterns of different heavy metals (additives) were used in the production of both degradable and non-degradable plastic bags by using the standard method with the help of Hands Held X-Ray Fluorescent (HHXRF) instrument. Samples results of the study showed Titanium, Calcium and Copper used in massive amounts, some of the toxic metals i.e., Arsenic, Lead, Cadmium, Chromium and Mercury were also detected. This study also reveals that degradable plastic bags might be more hazardous than non-degradable plastic bags because due to the Photolytic properties of additives used in degradable plastic bags when the chains of polymers break, the heavy metals are released in environment and become the part of it. So, concern department like Ministry of climate change and Pakistan Environmental Protection Agency should take serious step to control these serious issues.

The ultimate analysis parameters including carbon (C), hydrogen (H), nitrogen (N), and oxygen (O) content in biomass was rarely found to be predicted by nondestructive tests until to date. In this research, we developed partial least squares regression (PLSR) models to predict the ultimate analysis parameters of chip biomass using near infrared (NIR) raw spectra of non-wood and wood samples from fast growing tree and agricultural residue and nine different traditional spectral preprocessing techniques. These techniques include first derivative (sd1), second derivative (sd2), constant offset, standard normal variate (SNV), multiplicative scatter correction (MSC), vector normalization, min-max normalization, mean centering, sd1 + vector normalization, and sd1 + MSC. Additionally, we employed a genetic algorithm (GA), successive projection algorithm (SPA), multi-preprocessing (MP) 5−range, and MP 3−range to develop a PLSR model for rapid prediction. A dataset consisting of 120 chip biomass samples was utilized for model development in which the samples was non-wood samples of 65-67% and wood samples was 33-35%, and the model performance were evaluated and compared. The selection of the optimum performing model was mainly based on criteria such as the coefficient of determination in the prediction set (R2P), root mean square error of the prediction set (RMSEP), and the ratio of prediction to deviation values (RPD). The optimal model for weight percentage (wt.%) of C was obtained using GA−PLSR, yielding R2P, RMSEP, and RPD values of 0.6954, 1.1252 wt.%, and 1.8, respectively. Similarly, for wt.% of O, the most effective model was obtained using the multi-preprocessing PLSR−5 range method with R2P of 0.7150, RMSEP of 1.3088 wt.%, and RPD of 1.9. For wt.% of N, the optimal model was obtained using the MP PLSR−3 range method, resulting in R2P, RMSEP, and RPD values of 0.6073, 0.1008 wt.%, and 1.6, respectively. However, wt.% of H model provided R2P, RMSEP, and RPD values of 0.5162, 0.2322 wt.%, and 1.5, respectively. Notably, the limit of quantification (LOQ) values for C, H, and O were lower than the minimum reference values used during model development, indicating a high level of sensitivity. However, the LOQ for N, exceeded the minimum reference value, implying the samples to be predicted by the model must be in the range of reference range in calibration set. By scatter plot analysis, the effect of combined non-wood and wood spectra of biomass chips on rapid prediction of ultimate analysis parameters using NIR spectroscopy was investigated. To include different species in a model, the species have to be not only in the different values of the constituents to make a wider range for robust model but also they must provide their trend line characteristics in the scatter plot i.e. correlation coefficient (R), slope and intercept (same slope and slope approached to 1 and intercept is same (no gap) and approached zero, high R approached to 1). The effect of the R, slope and intercept to obtain the better optimized model were studied. The results show that the different species affected model performance of each parameter prediction in a different manner and by scatter plot analysis which of these species were affecting the model negatively and how the model could be improved was indicated. This is the first time of the effect is studied by the principle of scatter plot.

HDPE (high-density polyethene) plastic waste is stronger, harder, and more resistant to high temperatures than other plastics. Using it as an additive in a concrete mixture is one solution to reduce this type of waste. We examined how HDPE-type plastics can be used as an additive material in the manufacture of concrete to improve its hardness, tensile strength and compressive strength. Using 156 samples, we aimed to identify the effect of HDPE plastic fibres on concrete of three qualities; B0, f'c10 MPa (low quality), and f'c25 MPa (medium and high quality). We added four compositions (2.5%, 5%, 10% and 20% by weight of cement) of HDPE plastic fibre to each quality of cement, with HDPE plastic fibre sizes of 1 x 1 cm, 0.5 x 2 cm or 0.25 x 4 cm. We found that the addition of 5% HDPE plastic fibre with a 0.5 x 2 cm cross-sectional shape to the f'c10 MPa concrete gives the best result, with increased tensile and compressive strength of the concrete.

This study explores the perspectives and practices of architects regarding the reuse of wood in construction across five South-Central European countries: Slovenia, Serbia, North Macedonia, Bosnia and Herzegovina (BiH), and Montenegro. Based on a survey of architectural professionals, the research explores their attitudes, challenges, and motivations for using reclaimed wood, with a focus on circular construction principles. Key findings reveal unanimous agreement among re-spondents that both their profession and government entities inadequately support or promote wood reuse within the context of circular construction. While architects value reclaimed wood, there are country-specific variations. Environmental benefits, unique aesthetics, historical value, and sustainability are cited as primary motivators for reclaimed wood use. Additionally, re-spondents emphasize the ecological aspect as the most important consideration in wood product reuse, followed by economic and technological factors. Common concerns revolve around the long-term quality and maintenance of wood products. This research provides insights into the challenges and opportunities surrounding reclaimed wood use in South-Central Europe, high-lighting the need for support mechanisms and increased awareness to advance circular construc-tion practices in the region. These findings can have implications for architects and investors by identifying market opportunities, promoting eco-friendly practices, and providing valuable in-sights for future building designs with a focus on reclaimed wood elements within circular con-struction.

Seirogan, a wood creosote, is a nonprescription drug used to treat diarrhea. However, reports of its clinical use are rare. Here, we report on the efficacy of wood creosote (3 capsules daily) for the alleviation of diarrheal symptoms in 148 patients from 10 clinics in Japan. The wood creosote capsules were classified as remarkably effective (44 patients), effective (71 patients), and partially effective (13 patients) based on the degree of alleviation of diarrheal symptoms that were induced by a variety of causes. The antidiarrheal efficacy of the capsules did not differ between males and females, and young patients (21–30 years) showed greater improvement in diarrheal symptoms than did old patients (> 61 years). Although this report is based on the re-evaluation of old data that had been preserved by our company, the effectiveness and range of symptoms that were treatable with wood creosote has likely remained unchanged. To the best of our knowledge, this is the first public report on the clinical effectiveness of wood creosote capsules for the treatment of a wide range of diarrheal symptoms.

High level of noise is a disturbance to the human environment. Noise in industries is also an occupational hazard because of its attendant effects on workers’ health. Noise presents health and social problems in industrial operations, and the source is related to the machineries used in the industries. One of the unique features of the noise associated with wood machinery is the level of exposure and duration. Equipment used in a factory can be extremely loud. They can produce noise at decibels high enough to cause environmental health and safety concerns. The mechanically driven transport and handling equipment, cutting, milling, shaping and dust extractor installations in the wood industry generate noise. The sources of noise pollution have increased due to non-compliance with basic safety practices. The increased use of locally fabricated machine in the industry has increased the level of noise and vibration. The effects of industrial noise pollution as discussed include: increase in blood pressure; increased stress; fatigue; vertigo; headaches; sleep disturbance; annoyance; speech problems; dysgraphia, which means reading/learning impairment; aggression; anxiety and withdrawal. As presented in this paper, noise control techniques include; sound insulation, sound absorption, vibration damping and Vibration isolation.

Online artificial intelligence (AI) tools have recently gained in popularity. So-called “generative AI” chatbots unlock new opportunities to access vast realms of knowledge when being prompted by users. Here, we test the capabilities of two such AIs in order to determine the benefits for plastic surgery while also assessing potential risks. Future developments are outlined. We used the online portals of OpenAI’s ChatGPT(version 3.5) and Google’s Bard to ask a set of questions and give specific commands. Results provided by the two tools were compared and analyzed by a committee. For professional plastic surgeons, we found that ChatGPT and Bard can be of help when it comes to conducting scientific reviews and helping with scientific writing but are of limited use due to the superficiality of their answers in specific domains. For medical students, in addition to the above, they provide useful educational material with respect to surgical methods and exam preparation. For patients, they can help when it comes to preparing for an intervention, weighing in risks and benefits, while providing guidance on optimal post-operative care. ChatGPT and Bard open widely accessible data to every internet user. While they might create a sense of “magic” due to their chatbot interfaces, they nonetheless can help to increase productivity. For professional surgeons, they produce superficial answers - for now - albeit providing help with scientific writing and literature reviews. For medical students, they are great tools to deepen their knowledge about specific topics such as surgical methods and exam preparation. For patients, they can help in translating complicated medical jargon into understandable lingo and provide support for pre-operative as well as post-operative care. Such AI tools should be used cautiously as answers are not always precise nor accurate and should always be used in combination with expert medical guidance.

Polyurethane (PU) is a polymer widely used by humans whose recycling is highly complex due his chemical structure, being limited to incineration or accumulation in landfills. Biodegradation by enzymes and microorganisms has been studied for decades as an effective method of biological decomposition. In this study, Tenebrio molitor larvae (T. molitor) were fed with polyurethane foams, which gut enzymes and microorganisms were capable of degrading the polymer by 35% in 17 days of treatment, producing a weight loss of 14% in the mealworm. Changes in T. molitor gut bacterial community and diversity were observed, which may be due to colonization of species associated with PU degradation. Physical and structural biodegradation in PU by T. molitor compared to virgin PU, was demonstrated by Fourier Transform InfraRed spectroscopy (FTIR), Thermal Gravimetric Analysis (TGA) and Scanning Electron Microphotography (SEM).

Enhancement in the strength of austenitic steels with a small content of carbon can be achieved by a limited number of methods, among which is the ultrafine-grained (UFG) structure formation, especially efficient with the use of severe plastic deformation (SPD) processing that enables increasing significantly the contribution of grain-boundary strengthening, and also involves a combination of other strengthening factors (work hardening, twins, etc.). In this paper, we demonstrate that the use of SPD processing combined with conventional methods of deformation treatment of metals, such as rolling, may lead to an additional strengthening of UFG steel. Analysis of the results of the study on the change of the microstructure and mechanical properties of the Cr-Ni stainless austenitic steel after a combined deformation reveals a substantial increase in the strength properties of this steel, resulting from a consecutive application of SPD processing via equal-channel angular pressing and rolling at a temperature of 400 С, yielding a strength more than 1.5 times higher that that produced by any of these two methods used separately.

It is widely accepted that plastic waste is one of our most urgent environmental concerns the world is currently facing. Plastic has contributed greatly to innovation in all fields, but the raw material for its production (fossil fuels), as well as the linear economy in which it is currently produced and used, makes the material problematic from a sustainability and human health perspectives. The emergence of bio-based plastics provides an opportunity to reduce dependency on fossil fuels and transition to a more circular plastics economy. For polyethylene terephthalate (PET), one of the most prevalent plastics in packaging and textiles, there exist two bio-based alternatives that are similar or superior in material property and recyclability. These are polyethylene furanoate (PEF) and polytrimethylene terephthalate (PTT). The overarching aim of this study was to examine the transition from fossil-based to renewable plastics, through the lens of PET upcycling into PEF and PTT. The process for the production of PEF and PTT from three feed streams (post-consumer PET waste, lignocellulosic biomass-derived cellulose and biodiesel-derived crude glycerol) was developed in the software SuperPro Designer and the economic viability assessed via a discounted cumulative cash flow (DCCF) analysis. This study represents a conceptual case study of the valorisation of existing plastic waste into new, recyclable bio-based plastics, for a more sustainable plastics production. A techno-economic analysis of the designed process revealed that the minimum selling price (MSP) of second generation-derived PEF and PTT is 3.13 USD/kg, and that utilities and the feedstock used for the production of 2,5-furandicarboxylic acid (FDCA) needed in PEF synthesis contributed the most to the process operating costs. The effect of recycling PEF and PTT through the process at three recycling rates (42%, 50% and 55%) was investigated and revealed that increased recycling could reduce the MSP of the 2G bio-plastics (by 48.5%) to 1.61 USD/kg. This demonstrates that increasing recycling rates would have a beneficial effect on the economic viability of the plastic biorefinery.

The crack geometry and associated strain field around Berkovich and Vickers indents on silicon have been studied by X-ray diffraction imaging and micro-Raman spectroscopy scanning. The techniques are complementary, the Raman data coming from within a few micrometers of the indentation, whereas the X-ray image probes the strain field at a distance of typically tens of micrometers. For example, Raman data provides an explanation for the central contrast feature in the X-ray images of an indent. Strain relaxation from breakout and high temperature annealing are examined and it is demonstrated that millimeter length cracks, similar to those produced by mechanical damage from misaligned handling tools, can be generated in a controlled fashion by indentation within 75 micrometers of the bevel edge of 200mm diameter wafers.

Analysis of immediate effects of the COVID-19 pandemic on SMEs in Rwanda aims to assess and quantify the economic and financial impacts of the pandemic during the lockdown and presents options adopted by SMEs to reopen their business opera-tions. It also seeks to recommend options for sustainable and resilient economic recovery from the scars of COVID-19. This analysis used data collected from nearly 220 SMEs located across the country and applied an Exploratory Data Analysis (EDA) and multivariate linear regression models to measure the pandemic effects. The study revealed that firms downsized employment by 36.4 per cent, but data depict significant deviation within SMEs by their size. The COVID-19 pandemic has had a greater magni-tude of negative effects on sales levels among small businesses. Tax amounts were reduced amidst the crisis however, data do not show any significant variations among SMEs. Additionally, SMEs owners applied various coping mechanisms during re-opening. The study used firm-level data, providing detailed and reliable effects of the shocks on business performance. This analysis recommends establishing the medium-term financing and technical support for SMEs to ensure steady and sustainable recovery from pandemic effects as well as strengthening their resilience to any other socio-economics shocks.

Scientific studies on the impact of wood species on solid fuel production, performance, and sustainability are grossly inadequate. The knowledge of this is imperative as users of solid fuels are increasing rapidly, especially in Africa. On this note, it becomes necessary to explore measures that will improve its efficiency and sustainability as an energy source. This study investigates some properties of selected wood species used as an energy source in Nigeria and their pelleting potential. Nine (9) samples were characterized and assessed for suitability of pelleting following four wood pellet quality standards. The findings revealed Anogeissus leiocarpus as the species with the best rating score in terms of fuel properties while Vitellaria paradoxa as the lowest. However, in terms of conformity with the four wood pellets standards, Khaya senegalensis, Parkia biglobosa and Anogeissus leiocarpus having presented density, calorific value, sulfur, arsenic, cadmium, and lead within the limits of the wood pellet quality standards were considered the best wood species in terms of fuel suitability and pelleting potential. The findings therefore suggest that not all wood species are suitable as fuel. Thus, for species that do not meet the standard wood pellet requirements, alternatives such as the use of biomass blends, additives, or process adjustments can be employed to adapt the quality to the standards or by using the fuels in improved cookstoves.

The article presents the operation of the automatic pine sawn timber inspection system, which was developed at the Woodinspector company and offered commercially. The vision inspection system is used to detect various wood defects, including knots, blue stain, and mechanical damage caused by worms. Blue stain is a defect that is difficult to detect based on the color of the wood, because it can be easily confused with wood defects or dirt that do not impair its strength properties. In particular, the issues of detecting blue stain in wood, the use of artificial neural networks and improving the operation of the system in production conditions were discussed.

The Odunpazarı Modern Museum (OMM), conceptualized by Architect Kengo Kuma and inaugurated in 2019 in Eskişehir, stands as a testament to the historical significance of the timber trade in the region. The deliberate choice of wood as the primary construction material serves as a tribute to this historical narrative. The conspicuous incorporation of wooden lath materials into both the external and internal spaces signifies a conscious reference to the region's historical heritage and aligns with sustainability principles in design. The timber used to construct OMM was sourced from exhausted industrial pine forests. The creation of exhibition spaces at diverse scales involved the assembly of boxes of varying dimensions, illustrating OMM's inclination towards a formative structure characterized by “Addition and Integration.” This architectural methodology involves juxtaposing two or more primary forms to achieve a partial amalgamation. Factors such as form characteristics, dimensional distinctions, spatial arrangements, and extent of surface interactions collectively contribute to the compelling effect of this integrative approach. Within the confines of the museum, unconventional partitioning is implemented, and the strategic arrangement of masses results in multiple façades, even in the absence of overt wooden surfaces. The discernible visibility of the building's façade from an internal vantage point underscores the pivotal role played by wood in the architectural design of the OMM. The exterior impact of the wooden shell complements its interior application. The voluminous void at the heart of the structure allows for the infiltration of natural light into the internal spaces, and the wooden facade facilitates the transmission of light. The use of glass to segregate the cafeteria area from the museum entrance preserves a visual continuity between these spaces. The fundamental research inquiry in this study revolves around the user experience of wood, a material that actively influences diverse facets, including structural elements, contextual considerations, interior arrangements, and external aesthetics. To address this inquiry, a comprehensive case study and survey were conducted with the objective of elucidating the functional, sensory, perceptual, and psychological impacts of wood, the primary material in the museum's spatial configuration, on the overarching user experience.

The biofibres wide application as mortars enhancement have been so far restricted by factors related to their chemical composition and hygroscopic nature. Their hydrophilic behavior increases the water demand of mortar-mixtures and diminishes their adhesion to the matrix, while further moisture-related fibre degradation issues may arise. Additionally, the natural fibres seem to be susceptible to degradation caused during the exposure to alkaline environments conditions, such as those of cement mortars, restricting their utilization in construction industry. Therefore, the current study focusses on the potential of fibre modification through treatments that would permanently alter their structure and chemical composition in the whole mass or surface towards their performance improvement. In this study, mild hydrothermally treated wood fibres of black pine and beech species were prepared and incorporated in cement mortars to assess their performance, applying the proportion of 1.5% v/v in the mortar. The mortars workability (at fresh state), physical, hygroscopic, chemical, thermal, and mechanical characteristics at the age of 28, 90 and 365 days and weathering performance by subjecting them at different artificial ageing environments (freeze-thaw cycles or outdoor exposure) were examined. The results indicated the beneficial role of the treated fibres in the dimensional stability, flexural strength, thermal insulation properties and capillary absorption of the mortar specimens, especially during ageing process, with the black pine fibres to reveal the highest improvement. The hydrothermally treated wood fibres seem to ensure the integrity maintenance of cement mortars under all ageing conditions, proving that the specific bio-additives could provide low-cost and eco-friendly mortar enhancement pathways.

Micro and small wood-processing enterprises represent the heart of the European forest-based industries, being among the key drivers of economic growth in rural, mountainous, and poor regions. Their economic efficiency is of fundamental importance for their existence and the pro-vision of income for the local population in rural areas. Data Envelopment Analysis (DEA) is nonparametric, linear-programming-based approach, commonly used to analyse the efficiency of organizational units. This method allows estimating the economic efficiency of a certain eco-nomic system without assumptions about the functional form between resources and products. Furthermore, DEA determines the efficiency frontier and gives results of whether an enterprise, i.e., a Decision Making Unit (DMU) is efficient or not. The main objective of this study was to investigate and evaluate the economic efficiency of micro and small wood-processing enterpris-es in the EU countries and reveal the hidden inputs that facilitate efficiency generation. The eco-nomic efficiency evaluation was carried out on the basis of the official statistical data for the mi-cro and small wood-processing companies in the EU member states for the period 2015-2020 by performing a two-stage DEA analysis. The data used were standardized by value per employee. In addition to the first stage of DEA, fractional regression probit and logit models with four contextual variables were used to reveal the influence of the hidden inputs in the model. The results showed that the micro and small wood-processing enterprises can be regarded as more scale-efficient than technically-efficient entities. The only contextual variable affecting the eco-nomic efficiency was Investments per Person Employed, improving the efficiency by 2% per 1% increase of the investments.

Forest enterprise has been identified as a means of generating income among people; plays a vital role in enhancing the quality of life of forest-dependent people. Despite the opportunities timber marketing offers the people, the disparities in the income generation of the marketers in the Bodija sawn wood Market and the effect of socio-economic factors on income generation of the marketers is not well understood. This study was conducted to assess the socio-economic determinants of contributions of timber marketing to the income of timber merchants in Bodija sawn-wood Market. One hundred structured questionnaires were administered randomly in five zones of the sawn wood Market to obtain information on the socio-economic background of the sawn wood marketers and the contribution of timber trade to their incomes. The result indicated that 99.0% of the respondents were male while females constituted 1.00%. Seventy-five percent of the marketers had post-primary education and 25% had primary education. Two percent of the marketers had below 10 years of marketing experience, twenty-six percent had between 11 and 20 years, 57.00% had between 21 and 30 years, and 15.00% had more than 30years experience. Fifty-eight percent of the respondents earned between ₦10000-₦60000 (1US$ = 360.00) from timber marketing, thirty-one percent earned between ₦60001 and ₦110000, 7% earned between ₦110001 and ₦160000, while 4% earned above ₦160000 per month. Chi-square analysis of the socio-economic characteristics of the respondents and income generation at α level of 0.05 indicated that ethnicity (0.001) and years of experience (0.009) significantly influenced income while the level of education (0.101), age (0.122), and religion (0.745) had no significant influence on the incomes of marketers. Experience is an important factor in sawn wood marketing and a major determinant of the contribution of timber marketing to the income of timber marketers in Bodija sawn wood Market.

Wood-borer extermination by a dry heat clean-up is the essential method from the point of view of sustainability of historical wooden structures like trusses and ceilings in heritage-listed buildings. The wooden components are heated by a hot air of temperature about 100°C until the temperature in the centre of the wooden structures reaches 55°C to kill the wood-borers. In this article we review the method and present solution of the heat equation for structural wooden components. We also suggest an approximate formula that enables to estimate the necessary heating time for different cross sections of wooden components and can be used in technical application of the method.

The world’s population is growing at a rapid pace, thus increasing the need for shelter, which, because of increased carbon emissions, is making our planet less inhabitable. Thus, supplementary cementitious materials (SCMs) are used to reduce the embodied carbon emissions in the building sector. Wood ash, as a replacement for cement in soil treatment, seems to be a promising material. In this study, we considered the strength, stiffness, and microstructural behavior of marine clay treated with cement and wood ash as a cement replacement. Since clay is abundant in nature, it could help stabilize waste to improve the mechanical behavior of produced composites. Portland cement (7%, 10%, and 13%) was replaced with various amount of wood ash (5% and 10%) with two different dry densities (1400 and 1600 kg/m3) and three distinct curing periods (7, 28, and 60 days). Unconfined compressive strength, direct shear, porosity, pulse velocity, x-ray diffraction, and scanning electron microscopy tests were performed on selected specimens to evaluate the structural and microstructural effect of clay–wood ash–cement interaction. The results revealed that the replacement of cement with 5% of wood ash yielded superior performance. The microstructure investigation of wood ash–cement–clay blends further showed the formation of a densified matrix with stable bonds. Furthermore, the porosity and strength properties of blends developed unique relationships, which were further confirmed by other supplementary materials and soils.

Dynamic thermogravimetric (TG) analysis under nitrogen environment was used to understand the thermal decomposition process of 3D printing filaments made of wood-filled polylactic acid (PLA)/starch blend. The characteristic temperatures and apparent activation energy (AAE) of the filaments with various starch contents were calculated with well-known kinetic models by Friedman, Flynn-Wall-Ozawa, Coats-Redfern and Kissinger. With the increased starch content in the filament, the onset thermal decomposition temperatures of the filaments decreased gradually from 272.4 to 155.1°C. The thermal degradation degree became smaller, and the transitional temperature interval became larger with increased starch proportion. The AAE values of the three types of filaments with different starch ratios varied between 97 kJ/mol and 114 kJ/mol, depending on material composition and method of calculation. The improved understanding of thermal decomposition behavior of PLA-starch-wood composites can help develop more biodegradable PLA/starch-based filaments for 3D printing.

The color changes corresponding to chromophore structures in lignin caused by exposure of Eucalyptus（Eucalyptus grandis and E. urophylla）to heat were investigated. Eucalyptus wood samples were heated in saturated steam atmospheres for 10 h at 110℃, 130℃, and 150℃. The lignin was isolated before and after heat treatment. The physicochemical properties of the lignin and changes in chromophore structures during heat treatment was evaluated through wet chemical analysis, FTIR, UV-Vis, GPC, XPSand 13C-NMR. The color of the wood became darker and redder with the increase in pressure and temperature. Depolymerization and dehydration reactions occurred via demethoxylation with heat treatment in saturated steam at 110℃ or 130℃. Lignin condensed to form insoluble compounds after heat treatment in saturated steam at 150℃. G units increased and S units decreased through demethylation during heat treatment, as revealed by FTIR and 13C-NMR analysis.

Effects of plastic deformation on the indentation feature of hot-rolled commercial pure titanium alloy were detected using microindentation. It was found that the most deformed sample experienced the largest indentation resistance and had the maximum dislocation density and the indentation size influenced the CP-Ti indentation feature. The Vicker hardness and energy dissipated demonstrated the significant influence of the dislocation motion and size effects on the indentation in the indentation deformation. The linear relation of the energy ratio which is related to the microstructures and the indentation depth ratio was obtained for hcp materials Titanium alloys.

Cosmetic surgery is the subfield of plastic surgery that enhances appearance mainly for aesthetic reasons. Currently, cosmetic surgery interventions are highly considered appealing and popular all around the world. Several factors have contributed in this rapidly evolving field such as scientific and economic development, breaking down barriers and cultural norms, globalization, social media and mental disorders. Nowadays, the morality of cosmetic surgery is facing many dilemmas due to its benefits and drawbacks. It is proven that the advantages of cosmetic surgery include improved body confidence, mental health, and function. Additionally, aesthetic corrections can upscale the quality of life and create career opportunities for special targeted groups. Also, cosmetic surgery has a major impact in gender affirmation procedures. Although, herein we also describe the disadvantages of this widely developing field such as minor and major medical complications, potential postoperative risks and addiction in plastic surgeries associated with damaging economic issues. Lack in self-confidence, altered mental health status and ethical crisis consist another negative aspects of aesthetic surgery’s impact.

Monitoring and maintenance of cracked structures are generally done using structural integrity assessments. The plastic zone (PZ) crack path (CP) criteria state that a crack grows in the direction when the radius of the plastic zone ahead of the crack tip reaches a minimum value. The PZ can be evaluated using Stress intensity factors (SIF). The SIFs under mixed-mode loading were extracted from literature from three samples: two SENT samples made from polycarbonate and one modified C(T) sample made from low-carbon steel. In addition, the CP angle was evaluated for the W and R-criteria. It was found that both can predict the CP for lateral cracks in both tested materials and monotonic and cyclic load when the mode-mixity does not change considerably from one crack length to the next one or goes beyond 0.2. Moreover, the R-criterion exhibited an error as high as 1.7%, whereas the W-criterion showed a 6% error on the last crack length for the low carbon steel sample under cyclic load, which had a 100% increase in mode-mixity. Finally, the applicability of LEFM is checked, while the CP is sought by finding the size of the PZ.

Abstract. The paper presents primary material on determining the presence of micro- and macroplastics in Markakol Lake, one of the high-mountainous and unique water bodies of Kazakhstan, conditionally undisturbed, but vulnerable to anthropogenic pollution. In the course of work, micro- and macroplastics were detected in all selected samples in the water area of the lake and its main tributaries, the Urunkhaika, Topolevka, Tikhushka, Matabai, Elovka rivers. When determining micro- and macroplastics, we were guided by the method of analysis in aquatic environment, NOAA research program, developed by American scientists Masura J. et al, which is used in many countries. Concentrations and sizes of MP found in the water of the main tributaries of the rivers Urunhaika in concentrations up to 211.4 µg/m3, Tikhushka – 97.9 µg/m3, Zhirelka – 67.8 µg/m3, Topolevka – 157.2 µg/m3, Matabai – 78.3 µg/m3. Concentrations of MP in the surface water layer of the lake detected during 15 minute trawling at distances from 438 m to 841 m occur in sieve mesh sizes of 1.0 mm – 316.7 µg/m3 and 0.315 mm – 520.8 µg/m3. The total concentration of detected micro- and macroplastics coming with tributaries was – 150 µg/m3, in the lake water area – 837.4 µg/m3. The sizes of plastic debris found both in river waters and along the lake water area ranged from mesoplastic debris (fishing line net fragments, foam balls, plastic bags, plastic bottles, wrappers, food labels and packaging, etc.) to microplastic particles detected using a microscope with 40X magnification in size ranges of 25 mm, 1.0 mm and 0.315 mm. Sources of MP depend on local human activities (fishing, transportation, waste disposal etc.).

In this paper, we propose a modeling method based on peridynamics for ductile fracture at high temperatures. A thermoelastic coupling model combining peridynamics and classical continuum mechanics is used to limit the peridynamics calculations to the failure region of a given structure, thereby reducing computational costs. Then, a plastic constitutive model of peridynamic bonds is developed to capture the ductile-fracture process of the structure. Furthermore, an iterative algorithm for ductile-fracture calculation is presented. Finally, several numerical examples are shown. Particularly, the fracture processes of a superalloy structure under 800℃ and 900℃ environments are simulated and compared with experimental results. Our comparisons show that the crack modes captured by the proposed model are similar to experimental observations, which verifies the validity of the proposed model.

Excessive production, consumption and indiscriminate disposal of plastic waste cause an increasing plastic pollution with detrimental impacts on environment and human health. This study aimed to assess the level of knowledge, attitude, and practices (KAP) towards plastic pollution among Malaysians and evaluate the variation of plastic pollution related KAP among various socio-demographics. An online survey was conducted, and 294 valid responses was obtained. Descriptive statistics, KAP scoring and cross tabulation of responses were estimated. One-way analysis of variance, paired t-test and binary logistic regressions were carried out. Results showed that respondents had poor knowledge (mean 7.41 ± 1.80) and practice score (3.81 ± 1.39) across all socio-demographics. Compared to younger (18-30 years) respondents, older ones (>46 years) had higher knowledge (odds ratio, OR 4.304; p<0.01). However, middle aged (31-45 years) respondents reported significantly (p<0.01) higher attitude (OR 4.019) and practice (OR 4.056; p <0.05). Respondents with environmental related university education had showed higher odds about plastic pollution related knowledge (OR 10.343; p<0.01). Suggestions are made to undertake interventions such as environmental awareness creation, incorporating plastic pollution topics in formal and informal education, and providing recycling facilities nearby the localities for encouraging good practices towards minimizing plastic uses and pollution.

The present study was aimed to evaluate the suitability of agro-wastes and crude vegetable oils for the cost effective production of poly-β-hydroxybutyrate (PHB), to evaluate growth kinetics and PHB production in Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 with these carbon substrates and to study the biodegradation of PHB accumulated by these cultures. Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 accumulate higher amounts of PHB corn (79.90% of dry cell mass) and rice straw (66.22% of dry cell mass) medium respectively. The kinetic model suggests that the Pseudomonas sp. RZS1 follows the Monod model more closely than A. faecalis RZS4. Both the cultures degrade their own PHB extract under the influence of PHB depolymerase. Corn waste and rice straw appear as the best and cost-effective substrates for the sustainable production of PHB from Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1. The biopolymer accumulated by these organisms is biodegradable in nature. The agro-wastes and crude vegetable oils are good and low cost sources of nutrients for the growth and production of PHN and other metabolites. Their use would lower the production cost of PHN and the low cost production will reduce the sailing price of PHB based products. This would promote the large scale commercialization and popularization of PHB as ecofriendly bioplastic/biopolymer.

In this paper, an incremental eqivalent contact model is developed for elastic-perfectly plastic solids with rough surfaces. The contact of rough surface is modeled by the accumulation of circular contacts with varying radius, which is estimated from the geometrical contact area and the number of contact patches. For three typical rough surfaces with various mechanical properties, the present model gives accurate predictions of the load-area relation, which are verified by direct finite element simulations. An approximately linear load-area relation is observed for elastic-plastic contact up to a large contact fraction of 15%, and the influence of yield stress is addressed.

Astola Island is the first marine protected area of Pakistan acknowledged 2017, June 15. It is a rich biodiversity hotspot, Ramsar site inhabiting endangered species like Green turtle, Hawksbill turtle, and Arabian Humpback whale. A saw-scaled Russell’s viper is endemic to Island. Marine ecology of Astola Island is affected by plastic pollution resulting in coral destruction, ocean acidification, global warming, fishing nets blockage, water pollution, and coastal erosion. Zeolite catalyst synthesized from environmentally friendly way by coal fly ash to degrade collected plastic waste from Island into useful products in pyrolysis reactor. The synthesized catalyst functionalized further with three type of organosilane(1) Octyltriethoxysilane(OS),(2)Phenyltriethoxysilane(PS)(3)Vinyltriethoxysilane(VS).Zeolite functionalize with octyltriethoxy silane (ZO) shows the highest performance in plastic pyrolysis, resulting in lower degradation temperature, low residue and more product formation may be due to having long chain hydrocarbon and acidic sites. Plastic recycling is the promising solution to tackle plastic blooming issue. Which is negatively impacting all the compartments of ecosystem especially marine environment.

Demolished concrete and plastic waste are two increasingly aggravating problems. In this study, a novel method was proposed to simultaneously recycle concrete and plastic wastes by compacting concrete and plastic powders together under pressure and temperature. The influence of compression pressure and temperature as well as the mixture proportion on the bending strength of specimens was investigated. The results showed that pressure and temperature had a positive effect on the specimen strength; however, the molding temperature should not exceed the melting temperature of plastic. The proportion of plastic had a minimal effect on the bending strength of the specimen when plastic accounted for 25%–75% of the overall mass of the test piece.

Plastics are naturally hydrophobic materials so, in order to employ flotation for the separation of plastic mixtures, the use of appropriate wetting agents is mandatory. In this work, the effect of pretreatment with alkaline solutions of sodium hydroxide on the floatability of four plastics (PET, PS, PMMA and PVC) was studied. The influence of NaOH concentration, treatment time and temperature of the alkaline solution, and influence of particle size was analyzed. Results showed that alkaline treatment had a strong effect on PET floatability, some effect on floatability of PMMA and PVC and no effect on floatability of PS. Plastics floatability decreased with the increase of NaOH concentration, temperature and treatment time of the alkaline solution. Based on flotation behavior of simple plastics, flotation separation after alkaline treatment of bi-component mixtures of PET with PS and PVC was achieved efficiently. The best separation was obtained for PET/PS mixture, a floated with a grade of 98% in PS and a sunk with a grade of 100% in PET. PET/PMMA mixture led to the worst separation. For PET/PMMA and PET/PVC mixtures, flotation separation improved with the decrease of the particles size.

To extend the calculation power of tensor analysis, we introduce four new definition of tensor calculations. Some useful tensor identities have been proved. We demonstrate the application of the tensor identities in continuum mechanics: momentum conservation law and deformation superposition.

The outstanding occurrences of red wood ant nests (RWA; Formica rufa-group) at two study sites in the Oberpfalz, NE Bavaria, Germany, could be confirmed by the 2023 re-inventory (a total of 5,393 nests and an increase by ≈8 %). RWA nests preferred mature and medium mature pine-dominated forests. Standing and downed dead wood do not negatively influence nests. Nest counts with woodpecker cavities and the diversity of the herb layer increased. The highly clustered nests in NW-SE direction suggests a strong interaction between nests distributions and the tectonic environment. Our developed (re-)inventory approach in combination with the comprehensive photo database is a valuable tool for a) monitoring the entire forest habitat including woodpecker cavities and dead wood in, at and around nests, and b) identifying GeoBio-Interactions. Such a comprehensive approach leads to more accurate and realistic counts of RWA nests during (re-)inventories and provides scientific evidence of the status quo of RWA occurrence. Our results disproved the unfounded and scientifically unsubstantiated blanket statement by laymen of the ASW Landesverband Bayern e.V. that RWA nest numbers in the Oberpfalz or even in the entire Bavaria are in sharp decline. We suggest seven to eight years as a suitable time interval for re-inventories.

To understand how the thinning strategies impacts on wood quality and quantity for different purposes is of interest, considering that the management of plantations is carried out with parameters that have yet to be validated for different growth conditions. This work evaluated contrasting thinning regimes applied early at two moments of the crop cycle. With an initial population of 840 trees.ha-1, two thinning with populations ranging from 700 to 400, and from 400 to 100 trees.ha-1 were applied at 1.5 and 7.3 years, respectively. Growth analyses were carried out from the ages of 1.5 to 20.8 years considering: total height, diameter at breast height, individual volume, total and commercial volume per hectare, mean annual increase and current annual increase. At final age, contrasting populations of 100, 250 and 400 trees.ha-1 were sampled to assess wood density, and mechanical properties (bending and compression on small scale clear samples). The values of individual growth and wood properties are related to a Stand Density Index to understand the effect of competition on those values. The results allow us to identify the thinning schemes that record the most significant individual and per-hectare growth (both in thinning and clear felling) and the optimal harvest time under specific growth conditions. We assessed the proportions of commercial logs for sawmill and pulp uses, providing valuable inputs for a subsequent economic analysis of thinning regimes seeking for the most convenient combination of wood products. Wood's physical and mechanical properties assessed were barely affected by contrasting levels of competition between trees, therefore the decision of the silvicultural system to implement will depend on production and economic criteria.

This study investigates the impact of specimen size on the mechanical properties of wood, specifically focusing on compression strength, elastic modulus, and Poisson's ratio. Compression tests were conducted using three different specimen sizes (20mm×20mm×30mm, 40mm×40mm×60mm, 60mm×90mm×90mm) in the longitudinal, radial, and tangential directions. Mechanical parameters, failure mechanisms, load-displacement curves, and stress-strain relationships were systematically analyzed for each size. The study also evaluated the influence of specimen size on the accuracy of finite element numerical simulations by utilizing the obtained mechanical parameters. The results reveal a significant correlation between compressive strength and specimen size, indicating a decrease in compressive strength with increasing specimen size. Conversely, elastic modulus and Poisson's ratio exhibit less sensitivity to variations in specimen size. Notably, parameters derived from small-sized specimens (20mm×20mm×30mm) exhibited substantial errors, while those obtained from medium-sized (40mm×40mm×60mm) and large-sized specimens (60mm×90mm×90mm) demonstrated greater reliability, providing precise results in finite element numerical simulations.

When wood is thermally modified, several chemical reactions take place that change the chemical and physical properties of the wood. These changes correlate with the degree of modification, which is mostly a function of temperature and duration of modification, and consequently with a mass loss during this process. There is a lack of standardized quality control to verify the degree of heat treatment of wood and thus its quality. One of the possible methods to check the degree of thermal modification of a particular type of wood is thermogravimetry (TG). It is based on the assumption that processes that did not take place during thermal modification continue when the TG experiment is carried out. In this method, calibration curves have to be established based on TG measurements of standard samples that have been thermally modified at different temperatures and whose mass loss during modification is known. The calibration curves show the mass loss during the TG measurement as a function of the mass loss during the previous thermal modification. The course of thermal decomposition during the TG measurements is influenced by many parameters, such as the mass of the sample, the heating rate, the atmosphere in which the measurement takes place, and the shape of the crucible in which the sample is placed. In this paper, the influence of these parameters on the calibration curves was investigated. We have focused on oak wood. The best parameters result in a calibration curve with the largest correlation coefficient R2 and the highest slope of the line k. On this basis, we can determine the mass loss during thermal modification of unknown samples of the same wood species under the same measurement conditions.

The objective of this work was to improve the thermal stability, flame resistance and surface properties of black poplar (Populus nigra L.) wood via different impregnation methods. The impregnation method was employed through two distinct modalities: vacuum impregnation and immersion impregnation. Here, poplar wood was impregnated with calcium oxide solutions (1%, 3% and 5%). Fourier transform infrared spectroscopic analysis revealed a shift in the typical peaks of cellulose, hemicellulose, and lignin depending on the impregnation method and solution ratio. Thermogravimetric analysis and the limiting oxygen index indicated that the samples impregnated with lime solutions exhibited higher thermal stability than the unimpregnated wood. In both impregnation methods caused a decrease water absorption and thickness swelling of the sample groups. Using a scanning electron microscope, the effect of the impregnation process on the structure of the wood was examined. In terms of surface properties, it was determined that the surface roughness value increased. On the contrary, it was observed that the contact angle value also increased. A significant difference emerged between the applied methods. In conclusion, the applied lime minerals are suitable substances to increase flame resistance and thermal stability of black poplar wood.

Although the effect of thermal modification (TM) on teak wood color is well documented, a few studies were carried out in closed system processes, as well as it remains unclear the effect of different processes on the same material. This work aimed to verify the effect of closed and open system processes of TM on the color of fast-growing teak wood. Thermally modified wood was evaluated in a closed system at 160 °C (CS160) and in an open system at 185 °C and 210 °C (OS185 and OS210). We measured the moisture content (initial and final) of wood, and the corrected mass loss (CML). The chemical analyses encompassed the contents of alpha-cellulose, hemicelluloses, lignin, and extractives (total, in acetone and dichloromethane). Wood color was measured before and after TM according to the CIEL*a*b* color space. It was possible to achieve the same color using different processes of thermal modification (CS160 and OS210). TM reduced wood lightness (L*), red-green chromaticity coordinate (a*), and yellow-blue chromaticity coordinate (b*). L* and a* had the bigger and lower variations, respectively. The color of thermally modified wood was significantly changed, even at the mildest condition tested (OS185, 0.33% CML).

The goal of this study is to find out how some properties of wood-polymer nanocomposites are affected by the processing technology, the nanomaterials, and the ratio of coupling agents. To meet this objective, the extruded and dry blended samples are made from wood flour with MAPP, ZnO nanoparticles (0, 1, 3, and 5 wt%), and polypropylene. The mechanical properties of the nanocomposites improve significantly with ZnO and MAPP loading. Due to the more homogeneous structure of nanocomposites, better mechanical results are obtained with the extrusion method. With ZnO and MAPP loading, the thermal stability of nanocomposites improves. The storage and loss modulus values indicate that the processing technology of nanocomposites could be a key factor in the resistance of the materials obtained by extrusion. The storage and loss modulus of nanocomposites manufactured by the extrusion technology are determined to be higher than those of the samples produced by the dry blending method.

This review critically examines the various ways in which the mechanical properties of wood have been understood. Despite the immense global importance of wood in construction, most understanding of its elastic and inelastic properties is based on models developed for other materials. Such models neglect wood’s cellular and fibrous nature. This review thus questions how well models that were originally developed for homogeneous and effectively continuous materials can describe wood’s mechanical properties. For example, the elastic moduli of wood have been found by many authors to depend on the size of the test specimen. Such observations are incompatible with classical elasticity theory. There is also much uncertainty about how well elastic moduli can be defined for wood. An analysis of different models for size effects of various inelastic properties of wood shows that these models only approximate the observed behaviour, and do not predict or explain the scatter in the results. A more complete understanding of wood’s mechanical properties must take account of it being in some sense intermediate between a material and a structure.

In order to improve the performance of soft plantation wood, an environmentally friendly inorganic-organic hybrid wood modifier was developed. First, using urea and melamine as crosslinking agents, the waterborne glucose silicone resin (MUG) was prepared with glucose under the catalysis of inorganic acid and metal ions. Then MUG resin was diluted to 10% and 20% mass fraction, and compounded with sodium silicate (S) of 20% and 10% mass fraction, so the inorganic-organic hybrid G10S20 and G20S10 wood modifier were obtained respectively. Then plantation poplar wood (Populus tomentosa) were impregnated and modified with them. Their physical and mechanical properties were tested and compared with those of the wood treated with S of 20% mass fraction (S20). Infrared analysis showed that amino resin characteristic structure (CO-NH-) existed in MUG resin. The resin has good permeability. Compared with S20 modified wood, the degree of shrinkage of G10S20 or G20S10 modified wood is reduced, their moisture absorption is reduced, and their dimensional stability is improved. Waterborne glucose silicone modifier can effectively improve the wood density, modulus of elasticity, modulus of rapture and compression strength. SEM analysis showed that the cell wall of G20S10 modified wood was significantly thicker than the untreated wood, and there were columnar and granular solid substances attached in some cell cavities, ducts and corners, etc. EDX showed that the number of Si elements on the cell wall was significantly increased compared with the control, indicating that the modifier effectively entered the wood cell wall. The waterborne glucose silicone resin can greatly improve the physical and mechanical properties of wood through organic-inorganic hybridization. It is a green, non-formaldehyde, eco-friendly, low cost, compound wood modifier with broad application prospects.

The paper presents a model of moisture transport in wood taking into account diffusion and the accompanying adsorption of water vapour through the skeleton. A two-parameter form of the source term was proposed, depending on the distance of the current mass concentration of bound water from the equilibrium state. The tests on cubic samples with a side of 2 cm were carried out which allowed to determine the coefficients of the proposed model on the basis of the reverse method. The tests were performed for pine, larch, oak and ash in all directions of orthotropy. Also the tests on thin samples were performed to verify the source term.

There is a restricted knowledge about the potential impact of the use of different wood species on color and anthocyanin changes during the red wine aging process. This lack of knowledge is even greater when no oak wood species are used. Thus, the aim of this study was to carry out a comparative analysis of the impact of wood chip extracts from oak, acacia and cherry species on the chromatic characteristics and anthocyanins changes by the use of model wine solutions. In this context, several methodologies were used to quantified, color and anthocyanins changes during the aging time studied. The results indicated that the contact between wood chip extracts and grape skin isolated anthocyanin extracts induced a decrease of color intensity, particularly red color, and also the anthocyanin content in the different experimental model wine solutions studied. All chromatic modifications are potentially detected by human eyes because ΔE values were much higher than 3 CIELab units. These tendencies seems to be independent of the wood species used, but more pronounced for higher contact time between wood chip extracts and anthocyanins. The obtained results may contribute to a better understanding of the chromatic changes of red wines when aged in contact with different wood chips species.

Every year since the last fifty years, the world is waking up to higher and higher average temperature of the earth. Initially it was thought that this trend is a part of cyclical warming and cooling of the earth and nothing to be much worried about. However, with weather conditions become erratic and unusual over a large swath of the planet more and more frequently and regularly, scientists started to speak of Climate Change and people started to listen. In this paper we briefly discuss the link between global warming, climate change and current policies in the developing world to drive home the urgent need for alternative thinking. We briefly discuss the theoretical link between economic development and greenhouse gas emission and lay the micro foundation of the Environmental Kuznets Curve (EKC) before providing some evidence of global climate change and why this is a matter of concern for social scientists. Then we explore two avenues through which human activities are aggravating the situation especially in developing countries – the role of business architecture and the role of built architecture. We argue that these twin architecture are aggravating global warming by moving away from sustainable development policies.

Conventional methods for pathogen detection in water rely on time-consuming enrichment steps followed by biochemical identification strategies, which require assay times ranging from 24 hours to up to a week. However, in recent years, significant efforts have been made towards the development of biosensing technologies enabling rapid and close-to-real-time detection of waterborne pathogens. In previous studies, we developed a plastic optical fiber (POF) immunosensor using an optoelectronic configuration consisting of a U-Shape probe connected to an LED and a photodetector. Bacterial detection was evaluated with the immunosensor immersed in a bacterial suspension in water with a known concentration. Here, we report on the sensitivity of a new optoelectronic configuration consisting of two POF U-Shape probes, one as the reference and the other as the immunosensor, for the detection of Escherichia coli. In addition, another way of detection was tested where the sensors were calibrated in the air, before immersed in bacterial suspension and then read in the air, making the immunosensor more sensitive and with a faster detection time. This new sensor detected the presence of E. coli at 104 CFU/mL in less than 10 minutes. Currently sub 10 minutes is faster than previous studies using fiber-optic based biosensors. It is also a much simpler and quicker methodology when compared with conventional laboratory technology.

Agroforestry systems with multipurpose tree species, for the double production of timber and fruit, along with the intercropping with herbaceous crops, can be fundamental land use systems for multiple ecosystems services. Research was conducted in Italy, for one growing season, in 18 years old agroforestry experimental plots with common walnut (Juglans regia L.) trees, according to the previous agroforestry management (AFM) since tree planting. The aim is i) estimating trees growth and herbaceous yield in relation to increasing tree size, especially referring to the trees basal area (G); ii) evaluating the role of nut production as additional product to timber and food crops. Observations were run on tree growth and leaf phenology, total light transmittance (TTL) below tree canopy and hay yield with and without walnut intercropping. Nut yield was estimated from available literature and associated to G. At the end of the study year, representing two third of trees rotation, their height varied between 10 and 11 m, with much larger variation for tree diameter between 17 and 22 cm, according to the previous AFM, including tree mulching with plastic film. Hay yield varied between 4.5 and 3 Mg ha year-1 outside and under tree canopy, respectively. Negative regression were determined for G and TTL, and G and hay yield, with an annual reduction of 5% per G unit. Simulations were run on hay and nut yield, using G as main input parameter. The work points out the following key findings: i) the usefulness of plastic mulching, at tree planting, to increase the long-term timber productivity of the trees intercropped with herbaceous crops; ii) the negative linear relationship between hay productivity and walnut trees G; iii) G influences, in positive way, more markedly nut than hay yield. Suggestions are given on the optimum tree planting spacing and AFM for balancing timber, nut and hay yields.

Co-Zr amorphous alloys exhibit soft magnetic properties, whereas Co-rich crystalline magnetic phases in this alloy system display hard magnetic behaviour. In this study, an initial two-phase Co-Zr composite with an overall composition of 75 at.% Co and 25 at.% Zr was processed by high pressure torsion (HPT) and the effects of severe plastic deformation and subsequent thermal treatment on the structural evolution and its magnetic properties have been investigated. HPT processing allowed us to achieve an amorphous microstructure in the as-deformed state with low coercivity. To further tune magnetic properties and study the alloys’ crystallization behaviour, various annealed states are investigated. Microstructural properties are correlated to the magnetic properties and a decreasing coercivity with increasing annealing temperature is observed despite the onset of crystallization in the amorphous alloy. At higher annealing temperatures, coercivity increases again. The results appear promising to obtain tuneable rare-earth free magnetic materials by severe plastic deformation.

The reconstructive ladder is a well-established concept in Plastic Surgery proposed to achieve wound closure using a stepladder approach from simple to complex procedures and it continues to evolve from when it was presented for the first time. We describe a new surgical technique that allows skin excision and primary wound closure avoiding donor site morbidity from skin grafts and avoiding large scars from loco-regional flaps: the parallelogram excision technique. Fifteen patients with skin lesions underwent this procedure. Six months' follow-up results showed a) good scar healing, b) total excision of lesions, and c) patient acceptance and satisfaction from the usage of this technique. We conducted a geometrical analysis of the parallelogram’s design to study the optimal geometrical condition to achieve all these three factors. We propose that the parallelogram excision of skin lesions proves to be a unique new wound closure technique that may add a new rung to the reconstructive ladder.

Despite the increase in popularity of Zero Waste (ZW) concept, the successful implementation of this concept in waste management is still facing many challenges. The plastic recycling rate in Australia is currently only about 9.4%, which could leave up to 90.6% of plastic consumption being sent to landfills. The state of Victoria (in Australia) has proposed an ambitious plan to upgrade its waste and recycling system and to divert about 80% of waste from landfills by 2030. The aim of this research is to study Victoria’s current waste management plan and to develop a simulation model to assess the feasibility of it achieving zero plastic waste by 2035. In this direction, a fundamental knowledge of global ZW implementation needs to be acquired in order to understand the challenges, obstacles, and uncertainties in achieving ZW target. A simulation model is established using a method called double baselines. This method was developed as an improvisation to address the limitation of data availability for the model development. The model will run on 4 scenarios including one from Victoria’s current plan. Outcomes from the model are produced in comparative charts covering 6 key considerations including the rates of plastic consumption, waste to landfill, diversion, recycling, relative accumulative cost and effort. The findings of this study pointed out that Victoria’s current plan are feasible for its goal and presented with opportunities for improvement especially towards zero plastic waste. Besides, study results also reveal that the Victoria’s current plan to achieve 80% diversion rate by 2030 is possible but the zero plastic waste target by 2035 is less likely to happen.

Greenhouse have to provide optimal climate conditions for healthy plant growth and high production. Heating of greenhouses is required for an efficient and reliable production specially during winter time in Turkey. However, even in the temperate zones, heating costs has a great portion in the total production costs. Coal is preferred as a fuel in the greenhouse heating in provinces of Turkey where there is no geothermal energy. In this study, the heating requirements and fuel cost (fossil and geothermal energy) for Antalya, Afyon, Kütahya, Denizli, and Aydın provinces in the Aegean and Mediterranean region have been identified based on long term meteorological data. The calculations were made for two model greenhouses located in an area with 1 ha representing modern greenhouses of the regions. The first is a gothic roofed plastic model greenhouse and the second is a gable roofed polycarbonate model greenhouse. According to the results of calculations, total annual heatingrequirement values ranged from 6,096,283 (for Antalya) to 20,359,946 MJ/ha (for Afyon) for the plastic greenhouse wheras these values ranged from 3,187,074 (for Antalya) to 10,643,972 MJ/ha (for Afyon) for the polycarbonate greenhouse.

The evolution of metals micro/nano-structure upon severe plastic deformation (SPD) is still far to be theoretically explained, while experimental datasets are persistently growing for several decades. Major problem associated with understanding of SPD is related to a fact that the latter is a synergetic product of several competing physical effects which alter the material micro/nano-structure. In attempt to find deformational boundaries, where predominantly one mechanism determines the micro/nano-structure, in this paper we propose a continuous piecewise model for the analysis of experiments on material hardness vs strain of SPD processed materials. The novelty of this approach lies in its ability to find, as free-fitting parameters, the strain breakpoints which separate different micro/nano-structure modes generated upon SPD process. The model is applied to analyse experimental data for polycrystalline samples of pure iron and two distinctive strain breakpoints are revealed with good accuracies. This finding is in a good agreement with our earlier results on TEM microscopy studies on pure iron polycrystals after SPD treatment.

Metal matrix composite are used in such fields of technology, such as: aerospace, electronics, energy, industry, defense, automotive, aviation, shipbuilding, and more. Composite coatings of ceramic - metals is used primarily to enhance the durability of machine parts. Therefore, new materials are permanently looked for, what has resulted in the past in development of composite materials. The coatings dispersed are consisting of metallic matrix (metals and their alloys) and small non-metallic particles. The deposition of ceramic particles simultaneously with metallic matrix leads often to composite coatings possessing properties much better than those of metallic coating. The nickel and less often, other iron group elements are usually used as a matrix and Al2O3 as tough particles. The welding technology of applying alloy and composite coatings is widely used. The technology of infrasound thermal spraying of metal matrix composite coatings was presented. It is a simple technology and a very useful one in ship machinery regeneration during the cruise craft (e.g. internal combustion engines, torque pumps, separators). The metal matrix composite coatings must undergo finishing due to high surface roughness after application. In the article to used finishing by plastic working and machining of coatings nickel matrix composite was proposed.

Microorganisms drive the biogeochemical cycles that link abiotic and biotic processes in the aqueous environment and are intricately associated with plastic debris. The detection of microplastics in water and sediment introduces new concerns as small particle size allows for yet unconsidered pathways for plastics in the food web and element cycles. In this review, we present current knowledge of microbe-plastic interactions and summarize the potential impact of biogeochemical processes on plastic distribution, cycling, transport, and sedimentation. We explore how microbe-plastic interactions influence the exposure of consumers to plastics and plastic degradation products. Key methods used to elucidate biofilm development, microbial biodegradation, and plastic detection in the aqueous environment are discussed. Finally, we comment on potential future questions and research directions needed to further define the role of microorganisms in the environmental fate of microplastics.

The recyclability of polystyrene, acrylonitrile butadiene styrene, polystyrene and polyvinylchloride waste and using them as a source for 3D printing were studied. Filaments of about 3 mm in diameter were extruded successfully with a small-size extruder. The processed filaments were tested on a broad range of parameters - glass transition temperature, tensile properties and a pyrolysis scenario were obtained. The measured parameters were compared with parameters of virgin counterparts presented in the literature. In order to estimate the toxicity of the recycled material, elemental analysis of the samples was done.

1) Background: The objective was to evaluate the corrosion resistance of different commercially pure ultrafine-grained (UFG) titanium and its alloys with acid etched surface processed by equal-channel angular pressing (ECAP); 2) Methods: Coarse-grained and UFG titanium samples were investigated using polarization resistance technique. Surface characteristics of the native oxidized layer were evaluated by TEM and XRD. Electrochemical tests were under physiological electrolyte at a rate of 1 and 10 mV/s. Weight loss tests were performed after immersion into HCl solution for up to 3 years; 3) Results: UFG titanium was less susceptible to corrosion which was identified under lower rates and at higher polarization resistance than its coarse grain counterparts. Titanium Grade 2 and Grade 4 demonstrated similar corrosion susceptibility. Titanium Grade 5 revealed a thin and tightly adhered native oxide layer with adequate corrosion resistance; 4) Conclusions: ECAP process imposed a more compact and adhered oxidized layer. Surface etching techniques delivered a thicker native TiO₂ layer, being both grain refinement and surface etching techniques responsible for the improved corrosion resistance of Titanium samples under physiological environment after 3 years of observation.

In many developing countries, plastic waste management is left to citizens. This usually results in hazardous landfilling or open-air burning, leading to emissions that are harmful to human health and the environment. An easy, profitable, and clean method of processing and transforming the waste into value is required. In this context, this study provides an open-source methodology to transform low-density polyethylene drinking water sachets, into pavement blocks by using a streamlined do-it-yourself approach that requires only modest capital. Two different materials, sand, and ashes are evaluated as additives in plastic composites and the mechanical strength of the resulting blocks are tested for different proportion mix of plastic, sand, and ash. The best composite had an elastic modulus of 169MPa, a compressive strength of 29MPa, and a water absorptivity of 2.2%. The composite pavers can be sold at 100% profit while employing workers at 1.5X the minimum wage. In the West African region, this technology has the potential to produce 19 million pavement tiles from 28,000 tons of plastic water sachets annually in Ghana, Nigeria, and Liberia. This can contribute to waste management in the region while generating a gross revenue of 2.85 billion XOF (4.33 million USD).

Interference fits are a very common shaft-hub connection due to their low manufacturing cost and excellent technical properties. Plastic Conditioning of this machine element is a new and not very well known method. By exploiting residual stresses and the associated increase in the yield point, these components can absorb operating loads such as rotating bending moments, torsion, temperature changes and centrifugal forces purely elastically and avoid plastic deformation during operation. Compared to conventionally joined interference fits, the load bearing capacity in the elastic range can be increased by almost 200% and a specifically defined additional safety against plastic deformation in the elastic-plastic range can be ensured. This paper examines the effects of Reverse Yielding on the technology of Plastic Conditioning of Interference Fits in Power Transmission Engineering. Based on the Shear Stress Hypothesis (SH), the Plane Stress State (PSS) and the ideal plastic behavior of materials, the stress-mechanical relationships are explained, the influencing parameters are examined and conclusions are drawn for the plastic conditioning process. Taking into account the theoretical knowledge according to the state of the art, modified material behavior assumptions (isotropic hardening) and the Von Mises Yield Criterion (VMYC) are also considered. In addition, the method of plastic conditioning of interference fits is introduced and its basic principles are briefly explained. Along with computational suggestions to avoid Reverse Yielding, open issues requiring further research are identified.

To achieve a micro-destructive and rapid measurement of the wood density of standing trees, this study investigated the feasibility of using the micro-drilling resistance method, formulated a mathematical model, explored the potential for a unified model across multiple tree species, and analyzed the influence of moisture content on measurement accuracy. First, 231 tree cores and drill resistance data were sampled from Pinus massoniana, Cunninghamia lanceolate, and Cryptomeria fortunei. The basic density and moisture content of each core were measured, and the average value of each resistance data record was calculated. Second, the average drill resistance, the natural logarithm of average drill resistance, and absolute moisture content were used as independent variables, while the wood basic density was used as the dependent variable. Third, the total model of the three tree species and sub-model for each tree species were established through a stepwise regression method. Finally, the accuracy of each model was compared and analyzed with that of using the average basic density of each tree species as an estimated density. The results revealed that the estimation accuracy of the sub-model for each tree species was 1.670 percentage points higher than the average value of each tree species used as the density estimation value for these tree species. Additionally, except for Cryptomeria fortunei, the natural logarithm of drill resistance significantly influenced the wood density model at a significance level of 0.05. Moreover, moisture content significantly affected the total model and sub-models of Pinus massoniana at a significance level of 0.05. The estimation accuracy of the total mathematical model was 2.125 percentage points lower than that achieved using the average basic density of each tree species to predict their density. The results indicated the feasibility of using the micro-drilling resistance method to measure the wood density of standing trees. Moreover, the relationship between wood density and drill resistance did not follow a linear pattern, and moisture content slightly influenced the drill needle resistance. Furthermore, the establishment of a mathematical model for each tree species was deemed essential. This study provides valuable guidance for measuring the wood density of standing trees through the micro-drilling resistance method.

An enormous interest in the development of efficient protocols for cellulose extraction has been demonstrated in the last years, however, they were usually based on non-sustainable chemical and thermal approaches. In this work we describe a new and more sustainable method for cellulose extraction from eucalyptus and pine tree wood waste products exclusively performed using microwave-assisted radiation. The methodology includes 3 main steps: i) alkaline treatment; ii) bleaching I, using H2O2; and iii) bleaching II, an acidic treatment. Samples obtained in each step were characterized by Fourier-transform Infrared (FTIR) spectroscopy, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results were compared with those of starting materials, with the commercially available microcrystalline cellulose and with an industrial paper pulp. Results confirmed that for both type of wood wastes, cellulose was retained during the extractions procedures and that the removal of hemicellulose was achieved at the last step as seen by the FTIR spectra and TGA curves. The developed protocol is innovative since it constitutes an easy and quick approach to extract cellulose, from eucalyptus and pine tree wood waste using mild chemical and thermal conditions, microwave irradiation, and environmentally friendly purification steps. This approach offers the possibility of a future scale-up study to potentially apply the develop protocol to the extraction of cellulose in an industrial scale.

In the present study, the polysaccharide-hydrolyzing secretomes of Irpex lacteus BCC104, Pycnoporus coccineus BCC310, and Schizophyllum commune BCC632 were analyzed in submerged fermentation conditions to elucidate the effect of chemically and structurally different carbon sources on the expression of cellulases and xylanase. Among polymeric substrates, crystalline cellulose appeared to be the best carbon source providing the highest endoglucanase, total cellulase, and xylanase activities. Mandarin pomace as a growth substrate for S. commune allowed to achieve comparatively high volumetric activities of all target enzymes while wheat straw induced a significant secretion of cellulase and xylanase activities of I. lacteus and P. coccineus. A synergistic effect on the secretion of cellulases and xylanases by the tested fungi was observed when crystalline cellulose was combined with mandarin pomace. In I. lacteus the cellulase and xylanase production is inducible in the presence of cellulose-rich substrates but is suppressed in the presence of an excess of easily metabolizable carbon source. These enzymes are expressed in a coordinated manner under all conditions studied. It was shown that the substitution of glucose in the inoculum medium with Avicel provides accelerated enzyme production by I. lacteus and higher cellulase and xylanase activities of the fungus. These results add new knowledge to the physiology of basidiomycetes to improve cellulase production.

Botanical recycled concrete, or concrete bonded with wood, is formed by heat pressing the mixture of concrete and wooden waste. Botanical recycled concrete is a relatively new material and the relationship between production condition and its real-world performance is not clear yet. This experimental study investigated the influence of several production condition factors on the density and bending strength of botanical recycled concrete. As a result, temperature and mass ratio of concrete powder to wood flour presented significant effects on the density of this botanical recycled concrete. The increase in production temperature resulted in a remarkable increment in density and bending strength. This is probably due to increased wood flowability and accelerated compaction and bonding formation. The fineness of wood flour had a significant effect on improving bending strength. This is attributed to a larger contact surface between the wood substance and concrete particles.

COVID-19 pandemic is a serious problem in the world today. The SARS-CoV-2 virus that causes COVID-19 has important proteins used for its infection and development, namely the protease and spike glycoprotein. The RBD (Receptor Binding Domain) of spike glycoprotein (RBD-S) can bind to the ACE2 (Angiotensin Converting Enzyme-2) receptor at the protease domain (PD) (PD-ACE2) of the host cell, thereby leading to a viral infection. This study aims to reveal the potential of compounds contained in Curcuma sp., Citrus sp., Alpinia galanga, and Caesalpinia sappan as anti SARS-CoV-2 through its binding to 3 protein receptors. The study was conducted by molecular docking using the MOE 2010 program (licensed from Faculty of Pharmacy UGM, Indonesia). The selected protein targets are RBD-S (PDB ID:6LXT), PD-ACE2 (PDB ID: 6VW1), and SARS-CoV-2 protease (PDB ID:6LU7). The affinities of bonds formed is represented as a docking score. The results show that hesperidin, one of the compounds in Citrus sp., has the lowest docking score for all three protein receptors representing the highest affinity to bind the receptors. Moreover, all of the citrus flavonoids possess good affinity to the respected receptors as well as curcumin, brazilin, and galangin, indicating that those compounds perform inhibitory potential for the viral infection and replication. In general, the results of this study indicate that Citrus sp. exhibit the best potential as an inhibitor to the development of the SARS-CoV-2, followed by galangal, sappan wood, and Curcuma sp. that can be consumed in daily life as prophylaxis of COVID-19.

Plastic contamination of small dimensions (

Plastics play a pivotal role in the principles of a circular economy, where their effective recycling post-utilization, leading to economic value generation and minimal environmental harm, is crucial for achieving sustainable management. Extensive research has delved into the incorporation of waste plastics in concrete, showcasing promising outcomes with a myriad of advantages..The escalating volume of plastic waste is becoming a pressing issue, contributing to environmental pollution, particularly in densely populated cities and towns in Nigeria such as Delta, Aba, Port Harcourt, Onitsha, Enugu, Benue, and Ogun. These urban centers experience high consumption of goods packaged or sealed in plastic materials. Tourist destinations are also affected as large quantities of plastic waste are improperly disposed of or incinerated, resulting in environmental contamination and air pollution. Efforts to address this growing concern are crucial to safeguarding the environment and public health in these regions.Therefore, it is imperative to find effective ways to utilize these waste plastics. By cleaning low-density polyethylene bags and combining them with sand at specific proportions, high-strength bricks can be produced. These bricks not only exhibit thermal and sound insulation properties but also help in pollution control and cost reduction in construction projects. This innovative approach not only addresses the issue of accumulating plastic waste, a non-biodegradable pollutant, but also offers a sustainable solution to manage plastic waste while contributing to the construction industry's efficiency and environmental protection., By incorporating waste plastic and nylon into brick production, we not only reduce the amount of sand extracted from our natural resources like rivers and seas but also utilize the surplus plastic waste that is currently discarded. This research focuses on creating eco-friendly bricks by incorporating molten plastic, nylon, and plastic bottles in varying percentages (0 to 15% by weight) along with 5kg of fly ash. The experimental results from this study will shed light on the feasibility and benefits of using these materials in brick manufacturing, highlighting the potential of sustainable construction practices that minimize environmental impact and resource depletion, The experimental process involved utilizing cement and sand to complete the brick composition, with curing conducted underwater for 29 days followed by baking at temperatures between 100°C to 120°C for 2 hours. The resulting eco-friendly bricks exhibited key characteristics such as being lightweight, porous, having low thermal conductivity, and displaying appreciable mechanical strength. Interestingly, the compressive strengths of these bricks, post the addition of waste plastic and nylon, were found to be comparable to that of conventional bricks. Additionally, these eco-friendly bricks showcased reduced water absorption capacity compared to regular bricks, offering a promising alternative for sustainable and efficient construction practices.The eco-friendly bricks made from A, B, C, and D using 0%, 5%, 10%, and 15% plastic/nylon waste showed comprehensive strengths of 19.5 ,19.46, 20.3, and 21.1 respectively, with corresponding water absorption percentages of 0.34, 0.25, 0.22, 0.20, and 0.085. The efflorescence values were lower than those of normal bricks. These bricks are likely to enhance energy efficiency in buildings and provide economic value to manufacturers, thereby promoting a sustainable ecosystem for plastic waste management with the involvement of all stakeholders.

The accumulation of waste plastics has a severe impact on the environment, and therefore, the development of efficient chemical recycling methods has become an extremely important task. In this regard, a new strategy of degradation product-promoted depolymerization process was proposed. Using N,N'-dimethyl-ethylenediamine (DMEDA) as depolymerization reagent, an efficient chemical recycling of poly(bisphenol A carbonate) (BPA-PC) material was achieved under mild conditions. The degradation product 1,3-dimethyl-2-imidazolidinone (DMI) was proven to be the critical factor in facilitating the depolymerization process. This strategy does not require catalysts or auxiliary solvents, which is truly green process. This method improves the recycling efficiency of BPA-PC and promotes the development of plastic reutilization.

This study investigates the spatial and temporal distribution of litter at 7 beach sectors in Cadiz Bay, Southwest Spain. Two ten-day surveys carried out in autumn 2022 and spring 2023 revealed a total of 4,199 and 4,634 items, respectively, with plastic being the predominant material (71.13% in autumn, 88.39% in spring). Litter quantities varied significantly among beaches, La Puntilla showing the highest abundance with 0.48 ± 0.25 items m-1 in autumn and 1.34 ± 0.61 items m-1 in spring. The lowest abundance was recorded at sector 1 of Valdelagrana beach (0.08 ± 0.06 items m-1) during autumn and at El Castillito beach (0.08 ± 0.04 items m-1) during spring. Statistical analyses did not reveal significant differences in litter quantities between autumn and spring, however high significant interaction was shown considering both season and beach lo-cation. Seasonal differences were also observed in litter composition. Litter categories increased from 90 in autumn to 107 in spring. The top 10 litter categories varied between seasons and included cigarette butts, plastic fragments and plastic packaging. Cigarette butts were principally abundant in autumn because re-lated to summer beach users and wet wipes were particularly observed in spring because linked to wastewaters and river discharges especially relevant in winter months. Hydrodynamic and wind conditions were analyzed, revealing complex relationships with litter abundance.

Abandoned, lost, or otherwise discarded fishing gear (ALDFG) is a primary contributor to the entanglement of numerous marine species. Utilizing digital media platforms like Google, Facebook, and Instagram we conducted an assessment of the detrimental effects of ALDFG and plastic litter, on the biodiversity of Italy's marine ecosystem. Our investigation revealed that plastic litter has adverse consequences on various forms of marine life, including reptiles, mammals, birds, fish, crustaceans, and mollusks, along different Italian geographical sub-areas. Several records of interaction between plastic and endangered and vulnerable marine species have been described. Our reports even highlight the impact on marine turtles, mainly on Caretta caretta. This is the first report of entangled with fishing nets in Cetorhinus maximus, Oblada melanura, Serranus scriba, Homarus gammarus, Octopus vulgaris, and Phoenicopterus roseus. Furthermore, we identified that ghost nets have repercussions for endangered and vulnerable marine species. This update sheds light on the ongoing adverse effects of ghost nets on the Italian marine ecosystem, yet it is crucial to acknowledge that the true extent of the problem remains underestimated.

In this study, the autofrettage method, which is used to increase the durability of cylindrical parts, was applied to a barrel made of steel material according to the AISI 4340 standard. Assuming that the barrel works continuously under the pressure of 400 MPa, optimum autofrettage was performed. The stresses occurring on the barrel before and after autofretage were calculated. Additionally, analytical equivalent stress values (Von-Mises) formed on the part's wall were compared with numerical analysis results obtained with a commercial finite element program ANSYS®, and their compatibility was examined. As a result of the calculations and analysis performed, it was observed that autofretage has positive effect on increasing the pressure carrying capacity of the barrel. After autofrettage the cylindrical part, it was determined that the Von-Mises stress values formed in the part wall changed and these stresses took the lowest value at a point (elastic-plastic interface). It has been evaluated that this point gives the optimal autofretage pressure value for a certain operating pressure. After the autofrettage application, it was determined that the Von-Mises Stress value in the barrel wall decreased by 25.27 % and the pressure carrying capacity of the barrel increased without any design or dimensional change. It has been seen that the analytical and numerical analysis results are consistent with each other, and it is expected that this study will guide and contribute to the studies to be conducted on increasing the strength or lightening the weight of the parts.

Ranging from traditional food packaging, clothing, and furniture to the current small and large electronic devices and automobiles, plastics serve to fulfill diverse demands in our daily lives. However, the global plastic waste generation is dramatically escalating, currently standing at approximately 150 million metric tonnes annually. While some of regenerated plastics recycled by mechanical methods can be used as their parent plastics, cost and energy savings are limited by multiple preliminary processes such as plastic sorting, shredding, washing, and drying. Moreover, the continuous mechanical recycling process degrades the physical properties of the materials. In this context, chemical recycling is emerging as a promising alternative method due to its high efficiency, simple preliminary steps, reducing reliance on fossil resources, and conversion of plastic waste into value-added chemicals. This review provides a state-of-the-art overview of contemporary chemical recycling of polymeric materials via i) depolymerization: “polymers to small valuable molecules” and ii) closed-loop cycles: “polymers to monomers, and/or to polymers”, by encompassing both traditional/advanced depolymerization chemistries and the remaining challenges. These recycling approaches are contextualized within the present industrial technologies, key design principles, and specific recycling case studies related to distinct polymeric materials.

The drastically increasing amount of plastic waste is causing an environmental crisis that requires innovative technologies for recycling post-consumer plastics to achieve waste valorization while meeting environmental quality goals. Biocatalytic depolymerization mediated by enzymes has emerged as an efficient and sustainable alternative for plastic treatment and recycling. A variety of plastic- degrading enzymes have been discovered from microbial sources. Meanwhile, protein engineering has been exploited to modify and optimize plastic-degrading enzymes. This review highlights the recent trends and up-to-date advances in mining novel plastic-degrading enzymes through state-of-the-art omics-based techniques and improving the enzyme catalytic efficiency and stability via various protein engineering strategies. Future research prospects and challenges are also discussed

Polyethylene terephthalate (PET) pollution poses significant environmental consequences, and thus new degradation methods must be explored to mitigate this problem. We previously demonstrated that a consortium of three Pseudomonas and two Bacillus species can synergistically degrade PET in culture. The consortium more readily consumes Bis(2-Hydroxyethyl) terephthalate (BHET), a byproduct made in PET depolymerization, compared to PET, and can fully convert BHET into metabolically usable monomers terephthalic acid (TPA) and ethylene glycol (EG). Because of its crystalline structure, the main limitation of the biodegradation of post-consumer PET is the initial transesterification from PET to BHET, depicting the need for the transesterification step in the degradation process. Additionally, there have been numerous studies done on the depolymerization reaction of PET to BHET, yet few have tested the biocompatibility of that product with a bacterial consortium. In this report, a two-step process was implemented for sustainable PET biodegradation, where PET is first depolymerized to form BHET using an Orange Peel Ash (OPA) catalyzed glycolysis reaction, followed by complete degradation of the BHET glycolysis product by the bacterial consortium. Results show that OPA-catalyzed glycolysis reactions can fully depolymerize PET, with an average BHET yield of 92% (w/w) and that the reaction product is biocompatible with the bacterial consortium. After inoculation with the consortium, 19% degradation of the glycolysis product was observed in 2 weeks, for a total degradation percentage of 17% when taking both steps into account. Furthermore, the 10-week total BHET degradation rate was 35%, demonstrating that the glycolysis products are biocompatible with the consortium for longer periods of time, for a total two-step degradation rate of 33% over 10 weeks. While we predict complete degradation is achievable using this method, further experimentation with the consortium can allow for a circular recycling process, where TPA can be recovered from culture media and reused to create new materials.