One of the largest in the archipelago silver-copper mineralisation at Mount Sigurdf′ellet in West Spitsbergen Island was found in 1990 by Russian geologists. Firstly genesis was caused exclusively with hydrothermal ore migration of a substance from the enclosing sandstone and siltstone of the Devonian age. But subsequent work on the ore and nearest rocks of the basement gave a new factual material on the geochemical characteristics of potential sources of metals and found new for this mineral occurrence - gold mineralization. Similarity of geochemical associations of Sigurd ore occurrence with nearby upper Proterozoic marble as the first likely source of ore substance and the second - caused by carbonate-containing streaks in Low Devonian sediments. Ore-formation, probably due to repeated hydrothermal processes and was completed in a period of tectono-magmatic activity in Jurassic-Cretaceous time.

Long-term changes in nanoparticles of copper-silver bimetallic systems on natural clinoptilolite obtained by ion exchange of Cu2+ and Ag+, and then reduced at different temperatures, have been studied. Even after storage under ambient conditions, XRD and UV-Vis diffuse reflectance spectra indicate the presence of nanospecies of reduced copper and silver. Scanning Electron Microscopy of aged bimetallic samples, reduced at the highest temperature (450oC) and the primary samples for their preparation, also aged, showed the presence of silver nanoparticles with a size of about 100 nm. They are formed in the initial ion-exchanged sample (without reduction) due to the degradation of Ag+ ions. The nanoparticles in the reduced sample are larger; in both samples they are evenly distributed over the surface. The presence of silver affects the stability and the mechanism of decomposition/oxidation of reduced copper nanospecies, and this stability is higher in bimetallic systems. The decomposition pattern of recently reduced species includes the formation of smaller nanoparticles and few-atomic clusters. This can occur, preceding the complete oxidation of Cu to ions. Quasi-colloidal silver, which is present in fresh bimetallic samples reduced at lower temperatures, transforms after aging into Ag8 clusters, which indicates the stability of these nanospecies on natural clinoptilolite.

Copper, the highly toxicity micronutrient, plays two essential roles: it is a catalytic and structural cofactor for Cu-dependent enzymes, and it acts as a secondary messenger. In the cells, copper is imported by CTR1, a transmembrane high-affinity copper importer, and DMT1 (divalent metal transporter). In cytosol, enzyme-specific chaperones receive copper from CTR1 C-terminus and deliver it to their apoenzymes. DMT1 cannot be a donor of catalytic copper because it does not have cytosol domain which is required for copper transfer to the Cu-chaperons and following to cuproenzymes. Here we assume that DMT1 can mediate copper way required for regulatory copper pool. To verify this thought, we used CRISPR/Cas9 to generate H1299 cell line with CTR1 or DMT1 single knockout (KO) and CTR1/DMT1 double knockout (DKO). To confirm KOs of the genes qRT-PCR were used. Two independent clones for each gene were selected for further studies. In CTR1-KO cells, expression of the DMT1 gene was significantly increased. In subcellular compartments, copper concentration decreased dramatically in DKO cells. CTR1-KO cells, but not DMT1-KO, demonstrated reduced sensitivity to cisplatin and silver ions, agents that enter the cell through CTR1. The expression of genes, whose protein products require copper: HIF1α, XIAP, COMMD1, CCS, Cp, but not SOD1 and NF-kB, changed their level. Perhaps these data will help to understand how the disturbances of copper homeodynamics lead to the development of neurodegenerative and oncological disorders. Possibility of using CTR1 KO and DMT1 KO cells to study homeodynamics of catalytic and signaling copper selectively is discussed.

Sphalerite has been recognized as the most important carrier of critical metal of Indium (In) due to that In mainly exists in the sphalerite lattice by isomorphic substitution. There are two significant replacing schemes for In entry into sphalerite, these are, Ag++In3+→2Zn2+ and Cu++In3+→2Zn2+. In order to understand the reaction process and constraints of the two substitution schemes, this paper uses first-principles methods to calculate In and Ag, Cu replacing Zn in sphalerite. According to the substitution schemes of Ag++In3+→2Zn2+ and Cu++In3+→2Zn2+, two doped sphalerite systems of Zn30InAgS32 and Zn30InCuS32 were constructed using 2×2×2 supercell model of sphalerite. Firstly, the pressure is controlled to 30MPa, and the temperature is set from 20-40MPa to simulate the response of the two doped sphalerite systems to temperature; Then, the control temperature was unchanged to 600K, and the pressure was set from 20-40MPa to investigate the pressure control of the two doped sphalerite systems. The lattice parameters, substitution energy, electronic structure, and population analysis of the designed models before and after replacement have been critically compared. The main conclusions can be drawn that it is more stable for In to enter sphalerite via the coupled substitution scheme Cu++In3+→2Zn2+, and the conditions that the two substitution schemes most likely to occur are 650K and 40MPa. This study not only reveals the physical and chemical properties of In-rich sphalerite formed by the two reaction processes of Ag++In3+→2Zn2+ and Cu++In3+→2Zn2+, but also has a certain enlightenment effect on the search for indium in sphalerite, and promotes the application of first principles in mineralization analysis.

The importance of understanding the corrosion mechanisms of excavated metal artefacts help in determining the physico-chemical parameters of the burial environment and the formation of different corrosion products. These products can be observed and analysed with the help of various techniques that provide information on their morphology, chemical composition and structure. The analysis of ancient coins is extremely challenging in the presence of heavily corroded surfaces; as quantitative information may not exactly concur with its bulk composition. In the case of silver coins, the use of surface information can be used as a guide for bulk composition only. The current study carries out investigation and characterization of selected coins from a large coin hoard excavated from Amheida, Dakhla oasis, Egypt. The study and analysis of the alloy composition and corrosion products was performed using a multi-technique approach which included Light optical microscopes, Scanning Electron microscope (SEM) coupled with energy dispersive spectroscopy (EDS) and X-ray diffraction analysis. Investigation of the coins revealed the presence of a thick active inhomogeneous corrosion crust, while analysis showed that the coins were made from a binary silver copper alloy (billon) while the corrosion crust was rich in chlorides and carbonates, later identified by XRD analysis as Paratacamite, Malachite and Chrysocolla.

In order to design effective protective coatings against corrosion, the polyvinyl alcohol (PVA) as compound and composite with silver nanoparticles (nAg/PVA) were electrodeposited on copper surface employing electrochemical techniques such as linear potentiometry and cyclic voltammetry. A new paradigm was used to distinguish the features of coatings, i.e., a Deep Convolutional Neural Network (CNN) was implemented to automatically and hierarchically extract the discriminative characteristics from the information given by optical microscopy images. The main arguments that invoke a CNN implementation in the surface science of materials are the following: artificial intelligence techniques can be successfully applied to learn differences between surface coatings; based on their popularity for image processing, CNN can model images related to the problem of coatings; deep learning is able to extract the features that are distinguishable between material surfaces. To provide an overview of the copper surface, CNN was applied on microscope slides (CNN@microscopy) and inherently learnt distinctive characteristics for each class of surface morphology. The material surface morphology controlled by CNN without the interference of the human factor was successfully conducted, in our study, to extract the similarities/differences between unprotected and protected surfaces to establish the PVA and nAg/PVA performance to retard the copper corrosion.

There is much interest in effective copper chelators to correct copper dyshomeostasis in neurodegenerative and oncological diseases. In this study, a recombinant fusion protein for expression in E. coli cells was constructed from glutathione-S-transferase (GST) and the N-terminal domain (ectodomain) of human high affinity copper transporter CTR1 (hNdCTR1), which has three metal-bound motifs. Several biological properties of the GST-hNdCTR1 fusion protein were assessed. It was demonstrated that in cells, the protein was prone to oligomerization, formed inclusion bodies and displayed no toxicity. Treatment of E. coli cells with copper and silver ions reduced cell viability in a dose- and time-dependent manner. Cells expressing GST-hNdCTR1 protein demonstrated resistance to the metal treatments. These cells accumulated silver ions and formed nanoparticles that contained AgCl and Ag0. In this bacterial population, filamentous bacteria with length about 10 μm were often observed. The possibility for the fusion protein carrying extracellular metal binding motifs to integrate into the cell’s copper metabolism and its chelating properties are discussed.

Mechanical robustness, biocompatibility, and antibacterial performances are key features for materials suitable to be used in tissue engineering applications. In this work, we investigated the link existing between structural and functional properties of TiCu(Ag) thin films deposited by physical vapor deposition magnetron sputtering on Si substrates. The thin films were characterized by X-ray diffraction (XRD), nanoindentation, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). The TiCu(Ag) thin films showed complete amorphous structure and improved mechanical properties in comparison with pure Ti films. However, for contents in excess of 20% Ag, we observed the appearance of nanometric Ag crystallite. The TiCu(Ag) thin films displayed excellent biocompatibility properties, allowing adhesion and proliferation of the human fibroblasts MRC-5 cell line. Moreover, all the investigated TiCu(Ag) alloy display bactericidal properties, preventing the growth of both Pseudomonas aeruginosa and Staphylococcus aureus. Results obtained from biological tests have been correlated to the surface structure and microstructure of films. The excellent biocompatibility and bactericidal properties of these multifunctional thin films opens to their use in tissue engineering applications.

This study explores cutting-edge and sustainable green methodologies and technologies for the synthesis of functional nanomaterials, with a specific focus on the removal of water contami-nants and the application of kinetic adsorption models. Our research adopts a conscientious ap-proach to environmental stewardship by synergistically employing eco-friendly silver nanopar-ticles, synthesized using Justicia Spicigera extract as a biogenic reducing agent, in conjunction with Mexican zeolite to enhance contaminant remediation, particularly targeting Cu²⁺ ions. Structural analysis, utilizing X-ray diffraction (XRD) and high-resolution scanning and transmis-sion electron microscopy (TEM and SEM), yields crucial insights into nanocomposite structure and morphology. Rigorous linear and non-linear kinetic models, encompassing pseudo-first order, pseudo-second order, Freundlich, and Langmuir, are employed to elucidate the kinetics and equilibrium behaviors of adsorption. Results underscore the remarkable efficiency of the Zeolite-Ag composite in Cu²⁺ ion removal, surpassing traditional materials, achieving an im-pressive adsorption rate of 98% for Cu. Furthermore, the Zeolite-Ag composite exhibits maxi-mum adsorption times of 480 minutes. In the computational analysis, an initial mechanism for Cu²⁺ adsorption on zeolites is identified. The process involves rapid adsorption onto the surface of the Zeolite-Ag NP composite, followed by a gradual diffusion of ions into the cavities within the zeolite structure. Upon reaching equilibrium, a substantial reduction in copper ion concen-tration in the solution signifies successful removal. This research represents a noteworthy stride in sustainable contaminant removal, aligning with eco-friendly practices and supporting the potential integration of this technology into environmental applications. Consequently, it pre-sents a promising solution for eco-conscious contaminant remediation, emphasizing the utiliza-tion of green methodologies and sustainable technologies in the development of functional na-nomaterials

Classical antibacterial drugs were designed to target specific bacterial properties distinct from host human cells to maximize potency and selectivity. These designs were quite effective as they could be easily derivatized to bear next generation drugs. However, the rapid mutation of bacteria and their associated acquired drug resistance have led to the rise of highly pathogenic superbug bacterial strains for which treatment with first line drugs is no match. More than ever, there is a dire need for antibacterial drug design that goes beyond conventional standards. Taking inspiration by the body’s innate immune response to employ its own supply of labile copper ions in a toxic attack against pathogenic bacteria, which have a very low Cu tolerance, this review article examines the feasibility of Cu-centric strategies for antibacterial preventative and therapeutic applications. Promising results are shown for the use of Cu-containing materials in the hospital setting to minimize patient bacterial infections. Studies directed at disrupting bacterial Cu regulatory pathways elucidate new drug targets that can enable toxic increase of Cu levels and perturb bacterial dependence on iron. Likewise, Cu intracellular chelation/prochelation strategies effectively induce bacterial Cu toxicity. Cu-based small molecules and nanoparticles demonstrate the importance of the Cu ions in their mechanism and display potential synergism with classical drugs.

Information taken from David A. Scott’s book “Copper and Bronze in Art” was crucial for research on copper corrosion products in Stuttgart. Examples discussed are the nature and variability of ‘Black Spots’ (aka ‘Brown Fuzzies’); cupric hydroxide by cleaning, patination, and pigment synthesis; the wondrous phenomenon of curly malachite; chalconatronite formed by contact to soda glass; the formation of copper formates by glass-induced metal corrosion; and synthesis and X-ray diffraction of basic copper acetates (‘verdigris’).

Millions of people worldwide are affected by diabetes, a chronic disease that continuously grows due to abnormal glucose concentration levels present in the blood. Monitoring blood glucose concentrations is therefore an essential diabetes indicator to aid in the management of the disease. Enzymatic electrochemical glucose sensors presently account for the bulk of glucose sensors in the market. However, their disadvantages are that they are expensive and are dependent on environmental conditions, hence affecting their performance and sensitivity. To meet the increasing demand, non-enzymatic glucose sensors based on chemically modified electrodes for the direct electrocatalytic oxidation of glucose are a good alternative to the costly enzymatic-based sensors currently on the market, and the research thereof continues to grow. Nanotechnology-based biosensors have been explored for their electronic and mechanical properties, resulting in enhanced biological signalling through the direct oxidation of glucose. Copper oxide and copper sulfide exhibit attractive attributes for sensor application, due to their non-toxic nature, abundance, and their unique properties. Thus, in this review, copper oxide and copper sulfide-based materials, are evaluated based on their chemical structure, morphology, and fast electron mobility as suitable electrode materials for non-enzymatic glucose sensors. The review highlights the present challenges of non-enzymatic glucose sensors that have limited their deployment into the market.

This paper aims to review the challenges, toxicity, and routes of synthesis and usage of silver nanoparticles in different applications but also highlighting their sustainability from both medical and environmental issues. Regarding their toxicity, it is known that silver nanoparticles can destroy over 650 microorganisms comparing with antibiotics. Supplementary, will be presented in a comparative manner some conventional synthesis routes (physical and chemical methods) and green synthesis routes using plant extracts. The approach using plant extracts have various advantages comparing with physical, chemical and microbial synthesis methods because there is no need to use chemicals, wasteful purifications and high energy requirements. The paper presents an overview on “green nanotechnology” focused on using either biological micro-organisms or plant extracts as an alternative to the classical chemical and physical methods. An important issue discussed in the paper is an overview of the synthesis routes of silver nanoparticles, some expected applications of silver based active agents and their toxicity and challenges that must be overcome. Also, it needs to focus our attention on the dismissal of silver nanoparticles into the environment and especially in water systems, fact which suggests that this issue must be fully understood and applied the law.

The frequent occurrence of rib fractures in slaughtered lambs results in significant economic loss to producers and processors in South Australia and raises concerns about the welfare of the animals. The prevalence of rib fractures became evident through the Enhanced Abattoir Surveillance (EAS) program introduced in 2007. The present study aimed to investigate the association between rib fracture prevalence in lambs at slaughter and their nutrition and management on the farm of origin. The slaughter of 30,055 lambs from 60 farms was monitored at a South Australian abattoir in November 2016. Rib fracture prevalence was 4% (range 0 - 18% per consignment), with all consignments of more than 240 lambs having at least one with fractured ribs. Traceback investigation on 56 of the 60 farms suggests that rib fractures most probably occur during routine husbandry procedures and, based on soil mineral analysis, are associated with calcium inadequacy. There was substantial variation between lines of lambs from different farms, and factors contributing to the differences included line size, region, and soil characteristics, including available calcium. There is a need to modify sheep husbandry and management practices to improve sheep welfare and reduce the cost of rib fractures to the sheep industry.

Focused electron beam induced deposition is a versatile tool for the direct fabrication of complex-shaped nanostructures with unprecedented shape fidelity and resolution. While the technique is well-established for various materials, the direct electron beam writing of silver is still in its infancy. Here, five different silver carboxylates, three fluorinated: [Ag2(µ-O2CCF3)2], [Ag2(µ-O2CC2F5)2], [Ag2(µ-O2CC3F7)2] and two containing hydrogen: [Ag2(µ-O2CCMe2Et)2] and [Ag2(µ-O2CtBu)2] were examined and compared as potential precursors for focused electron beam induced deposition. All of the compounds show high sensitivity to electron dissociation and efficient dissociation of Ag-O bonds. The as-deposited materials showed high silver content from 42 at.% to above 70at.% and silver nano-crystal formation with impurities of carbon and fluorine incorporated between metal grains. A correlation of the number of carbon atoms in the precursor ligands and silver content of the deposited structures was found. The highest silver contents were achieved for compounds with the shortest CF chains. The deposited silver content depends on the balance of electron induced ligand co-deposition and thermal ligand desorption. Low electron flux is advantageous for high silver content. Our findings demonstrate that silver carboxylates constitute a promising group of precursors for focused electron beam nanoprinting of high silver content materials.

This research aimed to establish the relationship between carbon-nitrogen nutritional factors and copper sulfate on laccase activity (LA) by Pleurotus ostreatus. Culture media composition was tested to choose the nitrogen source. Yeast extract (YE) was selected as a better nitrogen source than ammonium sulfate. Then, the effect of glucose and YE concentrations on biomass production and LA as response variables was evaluated using central composite experimental designs with and without copper. The results showed that the best culture medium composition was glucose 45 gL-1 and YE 15 gL-1, simultaneously optimizing these two response variables. The fungal transcriptome was obtained in this medium with or without copper, and the differentially expressed genes were found. Main up-regulated transcripts included three laccase genes (lacc2, lacc6, and lacc10) regulated by copper, whereas the principal down-regulated transcripts included a copper transporter (ctr1) and a regulator of nitrogen metabolism (nmr1). These results suggest that Ctr1, which facilitates the entry of copper in the cell, is regulated by nutrient-sufficiency conditions. Once inside, copper induces transcription of laccase genes. This finding could explain why a 10 to 20-fold increase in LA occurs with copper compared to cultures without copper when using the optimal concentration of YE as nitrogen sources.

Computational investigations on the BPE-ligated Cu-catalysed enantioselective addition of enynes to ketones were performed with DFT method. Two BPE-CuMes catalysts, BPE-CuMes and (S,S)-Ph-BPE–CuMes, were employed to probe the reaction mechanism with the emphasis on stereoselectivity. The calculations on the BPE-CuMes system indicate that the actvie metallized enyne intermediate acts as the catalyst for the catalytic cycle. The catalytic cycle involves two steps: 1) the ketone addition to the alkene moiety of the metallized enyne; 2) the metallization of enyne followed by the release of product with the recovery of the active metallized enyne intermediate. The first step accounts for the distribution of the products, and therefore is the stereo-controlling step in chiral systems. In the chiral (S,S)-Ph-BPE–CuMes system, the steric hindrance is vital for the distribution of products and responsible for the stereoselectivity of this reaction. The steric hindrance between the phenyl ring of the two substrates and groups at the chiral centers in the ligand skeleton is identified as the original of the stereoselectivity for the titled reaction.

Molecular modeling studies were carried out at the DFT level of the adsorption of propane and propene on Ag surfaces as a model of the interaction of light hydrocarbons with Ag/ZrO2 catalysts for the catalytic combustion reaction. It was found that the most stable mode of adsorption of propene through its π system on Ag atom has energies consistent with chemisorption and generates an elongation of the C1=C2 bond, which would explain the increase in the activity of the catalysts as function of its metallic charge. The results obtained from the DFT calculations explain the different types of interaction between propene and propane with the metallic surface. The propene is chemisorbed on the Ag surface, distorting its bonds and generating its activation. This would imply that a higher metallic charge in the catalyst would increase the number of active sites in which this activation occurs, generating a higher activity. Besides, with the addition of O, the binding energy between the propene and the metal surface increased. On the other hand, the presence of a metallic surface is not enough for the activation of the propane molecule. This would explain why by increasing the amount of metal in the catalyst, the activity for the combustion of propane is practically not affected

Starch is a widespread natural polymer used in healthcare applications due to its low cost and antibacterial properties. The use of starch in its many forms and its sometimes combination with metallic nanoparticles have all contributed to the advancement of biomaterials. However, few studies have been conducted on biocomposites composed of jackfruit starch and silver nanopar-ticles (AgNPs). As a result, this research aims to study the physicochemical, morphological, and cytotoxic features of a Brazilian jackfruit (Artocarpus heterophyllus) starch-based scaffold loaded with AgNPs. Gelatinization and chemical reduction were used to synthesize the scaffold and AgNPs, respectively. X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy coupled with energy-dispersive spectroscopy (SEM-EDS), and Fourier transform infrared spectroscopy (FTIR) were utilized to explore the properties. The findings supported the development of anisotropic, stable, monodispersed AgNPs. The presence of AgNPs in the scaffold matrix was revealed by XRD and SEM-EDS. AgNPs were found to modify the crystallinity, roughness, and thermal stability of the scaffold while leaving its chemical and physical characteristics unchanged. Finally, the scaffolds did not show adverse effects on the L929 cells.

Hydrogel antibacterial agent is an ideal antibacterial material because of it could diffuses antibacterial molecules into the decayed area by providing a suitable microenvironment and the hydrogel acts as a protective barrier on the decay interface. The biocompatibility and biodegradation make the removal process easily which were widely used in medical fields. However, there have been few reports on its application for controlling postharvest diseases in fruit. In this study, the Chitosan-Ag (CS-Ag) complex hydrogels were prepared using the physical crosslinking method, which used for controlling postharvest diseases in grape. The prepared hydrogels were stable for a long period at room temperature. The structure and surface morphology of CS-Ag composite hydrogels were characterized by UV-Vis, FTIR, SEM, and XRD. The inhibitory effects of CS-Ag hydrogel on disease in grape caused by P. expansum, A. niger and B. cinerea were investigated both in vivo and in vitro. The remarkable antibacterial activity of CS-Ag hydrogels was mainly due to the synergistic antibacterial and antioxidant effects of CS and Ag. Preservation test showed that the CS-Ag hydrogel had positive fresh-keeping effect. This revealed CS-Ag hydrogels plays a critical role in controlling fungal disease in grape.

In this work, silver nanoparticles (AgNPs) were synthesized rapidly and eco-friendlily using the extract of Mulberry leaves and aqueous solution of silver nitrate without any toxic chemical [1,2]. The Mulberry leaves extract acts as both reducing agent and stabilizing agent. The UV-Vis spectrum shows peak at 430 nm. The TEM image of synthesized AgNPs sample shows spherical shaped particles whose size range from 15 to 20 nm. TEM image of nano silver solution sample synthesized by microwave assisted method shows nearly spherical particles with an average particle size of 10 nm. The absorption UV-vis spectrum of silver nanoparticles synthesized by microwave assisted method (AgNPsmw) shows a sharp absorption band around 415 nm. After two month storage of AgNPsmw, the absorption spectrum of AgNPsmw was taken again. The UV-Vis spectrum shows negligible peak changes of silver nanoparticles have occurred after two months of storage. The synthesized AgNPs material could be used as an antimicrobial, used in the field of textile and in wastewater treatment.

Pure silver as well as silver compounds have been used as antiseptics for centuries. Nowadays, the most frequently applied form of silver is a nanoparticle form. Several studies demonstrate the ability of silver nanoparticles and silver salts to accumulate in the brain of laboratory ani-mals as well as the ability of silver nanoparticles to influence behavioral and cognitive functions of laboratory mammals. For the first time, the influence of a silver salt, in particular, silver citrate on the change dynamics of behavioral and cognitive functions of laboratory mice at the daily oral exposure during 30, 60, 120 and 180 days is investigated in the present research. We observed the anxiety increase after 30 days of the exposure as well as the ability of mice to adapt to the prolonged oral exposure of silver citrate manifested in the anxiety decrease, increase of locomotor activity and the tendency of long-term contextual memory improvement. Increase of locomotor activity and memory improvement might be associated with the sensitivity increase and regarded as compensatory mechanism to anxiety increase. The observed phenomenon is classified as a hormetic effect. A comparison with the analogous study implemented polyvi-nylpyrrolidone coated silver nanoparticles is carried out. It was concluded that the nanoform is more neurotoxic.

Silver in different forms is used for medical purposes from ancient times. It is not yet well known, which form of silver is more biocompatible and less toxic. Here we considered silver nanoparticles and silver citrate. Also, the relationships of neurotoxicity of silver compaunds with ageing factor is not yet described. To assess the role of nanoform in neurotoxicity of silver and role of ageing a long-term experiment was conducted. We had four control groups of intact mice and four experimental groups which were exposed to silver nanoparticles and silver citrate for two months. Four groups of mice were introduced into the experiment since the age of five months to assess ageing factors. It was shown that the nanoform does play a certain role in neurotoxicity of silver. Silver citrate seems to be a more preferable silver compound. Ageing can be regarded as a positive factor that neutralizes toxic action of silver compounds. It may be due to the development of physiological/cognitive functions with the age as well as adaptation to unnatural content in the individual cages that is definitely stressful for mice.

Dispersed silver nanoparticles (AgNPs) on the surface of titanium alloy (Ti6Al4V) and titanium alloy modified by titania nanotube layer (Ti6Al4V/TNT) substrates were produced by chemical vapor deposition method (CVD) using novel precursor of the formula [Ag₅(O₂CC₂F₅)₅(H₂O)₃]. The structure and volatile properties of this compound were determined using single crystal X-ray diffractometry, variable temperature IR spectrophotometry (VT IR), and electron inducted mass spectrometry (EI MS). The morphology and the structure of the produced Ti6Al4V/AgNPs, and Ti6Al4V/TNT/AgNPs composites were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Moreover, measurements of hardness, Young’s modulus, adhesion, and surface free energy have been carried out. The ability to release silver ions from the surface of produced nanocomposite materials immersed in PBS solution has been estimated using inductively coupled plasma mass spectrometry (ICP MS). The wettability and the surface free energy of samples were estimated on the base of contact angle studies with the use of water and diiodomethane. Among the studied surface-modified titanium alloy implants, the best nano-mechanical properties were noticed for the Ti6Al4V/TNT15/AgNPs composite. The location of silver nanoparticles inside of titania nanotubes caused their lowest release rate, which may indicate on suitable properties above mentioned type of the composite for the construction of implants with a long term of antimicrobial activity.

This paper, the second in a series of two, describes the experimental results for removing arsenic from the dust collected in the electrostatic precipitators of a fluidized bed roasting oven (RP dust). The RP dust produced is discharged as a toxic waste, although its copper content is close to 20% by weight. This work aims to process the RP dust; until obtained a material with a low concentration of arsenic, which could be recirculated in smelting operations and recover the valuable metals. Based on the successful experience obtained in the first document with FS dust, this work proposes to use the reduction-sulphidation-volatilization processes to carry out the volatilization of arsenic from RP dust. A set of experiments was realized in the roasting different ratios of the mixture of copper concentrate / RP dust, sulfur / RP dust varying temperature and roasting time; to reach an arsenic concentration <0.5% by weight. The RP dust was characterized using different techniques, that confirmed more than 20% by weight of copper and describing its structure as a small particle agglomerate (<5 µm), with a complex sulfoxide morphology. The main results indicated: that for a 75/25 mixture of the copper concentrate / PR dust under 700 ° C, 15 minutes roasting time with air atmosphere, the arsenic volatilization was 96% by weight. Meanwhile, for a 5/95 mixture of sulfur / RP dust, at 650 ° C, the volatilization of arsenic was 67% by weight.

This paper (the first of a series of two) seeks to describe the experimental results of removing arsenic from dust collected in electrostatic precipitators of copper into the pyro-metallurgy gas cleaning systems. The first work corresponds to the treatment of dust contained in gas off generated in the copper Flash Smelting Furnace process (FS dust), while the second focuses on the treatment of dust generated from a Fluidized Bed Roasting Furnace (RP dust). The dust is complex sulphur-oxide-metals with concentrations of copper above 10 wt % and relatively high concentrations of silver. Due to the dust has an arsenic’s concentration above 5 wt %, makes it difficult to recover valuable metals through hydro-metallurgical processes or by direct recirculation of the dust into a smelting furnace. Thus, the development of pyrometallurgical processes aimed to reduce the concentration of arsenic in dust is the main purpose of this study, particularly the production of a material suitable for recirculation in smelting operations. The works conducted provide a detailed characterization of the dust, including Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN), Scanning electron microscope-Energy Dispersive X-ray analysis (SEM/EDS), X-ray diffraction (XR-D), elemental chemical analysis using Atomic Adsorption (A. A.) and X-Ray Fluorescence (X-RF). By considering that arsenic volatilization requires a process of reduction-sulphidation-volatilization, the works explore the roasting of mixtures of copper concentrate/dust, sulphur/dust and pyrrhotite/dust. The degree of volatilization was determined by elemental chemical analysis of arsenic in the mixture after and before the roasting process. The results indicated the effect of parameters such as temperature, gas flow, gas composition and the ratio of mixtures (concentrate, sulphur or pyrrhotite)/dust on the volatilization of arsenic. The findings indicate that the concentration of arsenic in the FS dust can be reduced to a relatively low level (<0.5 wt %), allowing to the material to be recirculated into smelting processes.

Impure and pure casts have collected reasonable attentions over all the world. In this paper, Aluminum (Al) and Copper (Cu) cast alloys are considered to be studied. Multiple impure and pure Al-Cu cast alloys are established under the condition of very high temperatures. Then, all of the established alloys are examined by applying mechanical tests. More specifically, tests of hardness are exploited. Moreover, different quenching conditions are employed and analyzed. These are the water, air and oil. Consistent results are separately obtained for the impure and pure materials.

Staphylococcus pseudintermedius (SP) is an emergent zoonotic agent associated with multidrug resistance (MDR). This work aimed to describe the antibacterial activity of four essential oils (EOs) and silver nanoparticles (AgNPs) against SP. Fifteen SP strains were tested. The four EOs, namely Rosmarinus officinalis (RO), Juniperus communis (GI), Citrus sinensis (AR) and Abies alba (AB), and AgNPs were used alone and in combination to determine the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) against SP. All strains presented MDR and methicillin resistance. Among the antibiotic cohort, only rifampicin, doxycycline and amikacin were effective. When EOs were tested alone, AB showed the lowest MIC followed by GI, RO and AR (0.23%±0.3; 0.5%±0.51; 0.79%±0.39; 0.93%±0.63). MBC was increased with the following order: AB, GI, AR and RO (3.56%±4.87; 4.93%±6.27; 8.53%±7.2; 10.34%±5.31). MIC and MBC values for AgNPs were 10.74 mg/L±4.23; 261.05 mg/L±172.74. In combination, the MIC and MBC values were lower for all compounds. In conclusion, EOs and AgNPs could be considered as promising antibacterial alternatives to antibiotics.

This study was conducted to recover valuable metals (silicon and silver) using acid leaching and substitution reactions with copper powder from the pulverized solar cell separated from the PV ribbon. Leaching experiments were conducted according to nitric acid concentration by molar solution as 1M, 2M, and 3M using an ultrasonic cleaner at a reaction temperature of 60 °C for the leaching times of 30 to 120 minutes. Si phases were detected at all leaching reaction times, it was confirmed that the aluminium was removed effectively if the nitric acid leaching time was more than 30 minutes, and silicon with a purity above 99% could be recovered. The silver was precipitated by adding copper, which has greater reducibility than Cu, Al, Si, Pb, and Sn. When the addition of copper powder was 0.75 and 1.0 g, precipitate was produced 0.23 and 0.55 g, respectively. The optimal condition for the recovery of silver by the addition of copper powder was 1 g, where is recovery rate reached 93.3%.

Introduction: Silver nanoparticles have been extensively investigated in dental and orthopedic materials. However, the impregnation of bone graft with silver nanoparticles has been poorly investigated. Objectives: The aim of this study was to evaluate the in vitro antibiofilm activity of a bovine bone impregnated with silver nanoparticles. Methods: Bone scaffolds from cancellous bovine femur were used for the tests and impregnated with silver nanoparticles (50nm) by physical adsorption. Silver nitrate minimal inhibitory and bactericidal concentration were performed Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, Enterococcus faecalis, Acinetobacter baumannii, and Escherichia coli. Disc diffusion tests for silver nanoparticles susceptibility and quantification of biofilm production on plate and bone with sessile cell count were also performed. Results: All pathogens were susceptible to silver with low minimal inhibitory concentration (0.25 – 4 mg/L). The scaffold impregnated with silver nanoparticles presented a significant reduction in the biofilm cells for all microorganisms with a reduction of more than 3 logs in colony forming units count. Conclusion: Bone scaffolds impregnated with silver nanoparticles can significantly reduce biofilm, and it can be a strategical material to be used as an implant for different approaches.

Abstract: Given the increasing resistance of some bacterial strains to many common antibiotics used in the local market, the current study aimed to produce nanoscale particles capable of combating pathogenic bacteria that have developed resistance to current antibiotics. In this research, an ex-perimental study was conducted to produce nanoscale particles using the single-celled blue-green algae Synechococcus sp., which was isolated from a local environment in the Arab Republic of Egypt, specifically from a soil sample in Beni-Suef City. The aim of the study was to generate silver NPs employing different biological approaches, encompassing the direct strain powder technique, ethanol extract pellet technique, and ethanol extract technique. These synthesized nanoparticles displayed different shapes, including cubic, spherical, pellet-like, and rod-shaped particles. They were characterized by bio-functional groups containing Ag+ ions, which were detected using FT-IR, Zeta sizer, and Zeta potential measurements. High-resolution SEM imaging unveiled the mor-phological features of Silver NPs with biologically formed protective layers, spanning sizes from 20 to 430 nm for individual particles. The study evaluated the antibacterial efficiency against both G+ve and G-ve bacteria. The ethanolic extract technique exhibited the largest inhibition zone (24 mm) against G+ve bacteria, particularly Staphy. aureus. Furthermore, it was observed that the larger particles produced using the powder and pellet techniques were less effective antibacterial agents. In conclusion, this investigation emphasizes the potential of cyanobacteria-based synthesis of silver nanoparticles as a promising approach for producing innovative antimicrobial agents.

Introduction: Infections associated with medical implants pose significant challenges to healthcare, demanding the development of new effective antimicrobial strategies. This study focuses on the creation of a novel biological membrane with enhanced antimicrobial properties by with the incorporation of either vancomycin or silver nanoparticles. Methods: Pericardium samples were impregnated with either silver nanoparticles (AgNPs) or vancomycin (VAN). The antimicrobial activity of the membranes was assessed through qualitative microbiological analysis, biofilm production and animal in vivo model of infection. Histological analysis was performed on the pericardium samples, and quantitative microbiological analysis was conducted on the tissue from the animal model and biocompatibility evaluation. Statistical analyses were carried out using appropriate tests. Results: Microbiological tests confirmed both VAN and AgNP showed inhibition halos against bacteria. Histological analysis indicated minimal inflammatory response and bacterial presence in VAN and AgNP groups compared to the control group revealed reduced bacterial presence. Biomechanical testing showed that polypropylene had the lowest tensile strength, while AgNP-impregnated pericardium exhibited lower resistance than VAN-impregnated and control pericardium. Conclusion: Lyophilized and decellularized bovine pericardium as a substrate, combined with the incorporation of vancomycin or silver nanoparticles, provides a versatile platform for combating infections associated with medical implants.

The invention of nanoscience not only brings a revolutionary change in the field of science but also changed the direction of research. Today the whole world is under the trigger of nano and nanoparticles have multidimensional applications in every aspect of life including environmental point of view. Till today a plethora of nanoparticles have been synthesized and have also been applied for multiple purposes and hence grabbed the attention of researchers all over the world. Among the bunch of NPs discovered to date, we have a particular interest in silver nanoparticles (AgNPs) because of their cost-effectiveness and huge abundance in the earth’s crust. With respect to every passing day, due to various kinds of anthropological activities, the quality of the environment such as air, water and soil is depleting which ultimately hampers the human civilization. To encompass the growing environmental issues, many techniques have been adopted. Among the many strategies, tackling the current issues regarding environment through nanoscience is highly worthy as because of its cost-effectiveness, less time consuming and easy handling process. This article reviews the potential of nanoparticles, particularly silver nanoparticles, for a wide range of environmental applications, such as soil, air, and water remediation.

The accumulation of microorganisms, plants, algae, or small animals on wet surfaces that have a mechanical function causes biofouling, which can result in structural or other functional deficiencies. The maritime shipping industry must constantly manage biofouling to optimize operational performance, which is a common and long-lasting problem. It can occur in any metal structure in contact or submerged in ocean water, which represents additional costs in terms of repairs and maintenance. This study is focused on the production of antifouling coatings, made with nanoparticles of copper selenide (CuSe) modified with gum arabic, within a water-base acrylic polymeric matrix. During the curing of the acrylic resin, the CuSe NPs remain embedded in the resin but this does not prevent the release of ions. The coatings presented to release copper and selenium ions for up to 80 days, selenium was the element that was released the most. The adhesion of film coatings to metallic substrates showed good adhesion, scale 5B (ASTM D3359 standard). Antimicrobial activity tests show that the coatings have an inhibitory effect on Escherichia coli and Candida albicans. The effect being more noticeable when the coating is detached from the substrate and placed on a growing medium, than compared to the coating on a substrate. Scanning electron microscopy (SEM) observations show that nanostructured CuSe coatings are made up of rod-shaped and spherical particles whose range ranges from 12 to 25 nm. The Energy Dispersive X-ray spectroscopy (EDS) studies showed that the ratio of selenium nanoparticles is greater than that of copper and that their distribution is homogeneous

The exponential growth in the consumption of electronics, in combination with the reduction in their useful life, leads to a significant increase in the volume of electronic material discarded. Printed Circuit Boards (PCBs) are modules composed of ceramic, polymer and metallic materials of high economic value and with a great potential for damage to biotic and anthropic environments when inadequately discarded. The aims of this work was to study the main environmental impacts and the efficiency of mechanical operations in the electronic waste recycling process in optimizing the concentration of metallic copper. For this, the samples obtained were characterized according to their morphology and chemical composition, and subjected to physical and mechanical treatments: dismantling, grinding, separation by granulometry, density and magnetic property. The environment impacts were estimated by the Life Cycle Assessment of the pre-treatment processes, associated with copper extraction operations in WPCBs. According to the results obtained, it is possible to infer that the NM +1mm Concentrated product presents in its metallic composition around 78% of copper, which contributes to the efficiency of the hydrometallurgical extraction processes. It is noteworthy that the Concentrated class represents about 14% of copper (wt) taking into account the amount of 3.789 kg of PCB waste input material. The potential for reinsertion of the dust in the material recovery process is highlighted, given that the chemical composition of this particulate has a significant presence of metals. In general, it was found that due to the higher concentration (wt %) of the sample being allocated in the range of - 0.15mm + 0.05mm, the elements Fe (18.30%), Si (10.73%), Ca (9.21%) and Cu (8.89%) stand out regarding the participation of the elemental composition of this fraction and also regarding the general composition of the sample. Furthermore, the generation of dust during the fragmentation process, can be associated with occupational respiratory diseases when not managed. About the Life Cycle Assessment, in seven of the nine categories evaluated, crushing and screening activities accounted for more than 90% of the recorded impact values. In general, it is estimated that in the pre-treatment phase be generated 15.4 kg CO2 eq.

The study of the inherent factors that influence the isolation of one type of metallosupramolecular architecture over another is one of the main objectives in the field of Metallosupramolecular Chemistry. In this work, we report two new neutral copper(II) helicates, [Cu2(L1)2]·4CH3CN and [Cu2(L2)2]·CH3CN, obtained by means of an electrochemical methodology and derived from two Schiff-based strands functionalized with ortho- and para-t-butyl groups on the aromatic surface. These small modifications let us to explore the relationship between the ligand design and the structure of the extended metallosupramolecular architecture. The magnetic properties of the Cu(II) helicates were explored by EPR spectroscopy and DC magnetic susceptibility measurements.

The development of oxidation processes with generating powerful radicals is the most interesting and thought-provoking dimension of peroxymonosulfate (PMS) activation. In this study, a magnetic spinel CuFe2O4 was successfully prepared by a facile, non-toxic, cost-efficient co-precipitation method with the synergetic effect of photocatalytic PMS oxidation against recalcitrant benzotriazole (BTA) pollutant. The high particle dispersion and large surface area (201.898 m2/g) provided a high photocatalytic activity with CuFe2O4. The obtained results from the central composite design (CCD) analysis confirmed the optimum degrading rate of BTA reached 81.4% at the optimum operational condition of CuFe2O4= 0.4 g/L, PMS= 2 mM, BTA= 20 mg/L after 70 min irradiation time. As such, the active species capture experiments revealed the presence of •OH, SO4•‒, O2•‒ and h+ species in CuFe2O4/UV/PMS system where SO4•‒ was dominated for BTA photodegradation. The combination of photocatalysis and PMS activation enhanced the consumption of metal ions in redox cycle reactions, thus preventing metal leaching and maintain the recyclability with reasonable mineralization efficiency which achieved more than 40% total organic carbon removal after four batch experiments. A retardant effect on BTA oxidation was observed with comparing the water’s common anion constituents as HCO3‒ > Cl‒ > NO3‒ > SO2‒. Results from intermediates identification showed that the transformation pathway of BTA developed as the deprotonation, hydrolysis and ring cleavage processes promoting the practical potential of photo-absorbing CuFe2O4 catalyzed PMS which can be a promising method due to convenient magnetic separation form the solution.

Metal bioaccumulation and metallothionein (MT) expression were investigated in gills and liver of the red-blooded Antarctic teleost Trematomus hansoni with the aim to evaluate the possibility for this species to face, with adequate physiological responses, an increase of copper or cadmium concentrations in the environment. Specimens of this Antarctic fish were collected from Terra Nova Bay (Ross Sea) and used for a metal exposure experiment in controlled laboratory condi-tions. The two treatments lead to a significant accumulation of both metals and an increase of gene transcription only for the MT-1. The biosynthesis of MTs was verified especially in speci-mens exposed to Cd, but the majority of these proteins were soon oxidized, probably because they were involved in cell protection against the risk of oxidative stress, by reactive oxygen spe-cies scavenging. The obtained data highlighted the phenotypic plasticity of T. hansoni, a species evolved in an environment characterized by natural high concentrations of Cu and Cd, and maybe the possibility for the Antarctic fish to face the challenges of a world that is becoming every day more toxic.

This work discussed the advantages of reducing copper in molten copper slag with low S content. FactSage calculated the distribution of copper at equilibrium under different sulfur content. The effect of sulfur content on copper recovery under different oxygen partial pressures was pointed out. The effect of sulfur content on copper recovery in the actual reduction process was explored through experimental research. Under the condition of low sulfur, the Recovery of copper and the stability of the experiment have an ideal results.

In the human body, Copper (Cu) is a major and essential player in a large number of cellular mechanisms and signaling pathways. The involvement of Cu in oxidation-reduction reactions requires close regulation of copper metabolism in order to avoid toxic effects. In many types of cancer, variations in copper protein levels have been demonstrated. These variations result in increased concentrations of intra-tumoral Cu and alterations in the systemic distribution of copper. Such alterations in Cu homeostasis may promote tumor growth or invasiveness, or even confer resistance to treatments. Once characterized, the dysregulated Cu metabolism is pinpointing several promising biomarkers for clinical use, with prognostic or predictive capabilities. The altered Cu metabolism in cancer cells and the different responses of tumor cells to Cu are strongly supporting the development of treatments to disrupt, deplete or increase Cu levels in tumors. The metallic nature of Cu, as a chemical element, is key for the development of anticancer agents via the synthesis of nanoparticles or copper-based complexes with antineoplastic properties for therapy. Finally, some of these new therapeutic strategies such as chelators or ionophores have shown promising results in a preclinical setting, while others are already in the clinic.

Predicting copper price is essential for making decisions that can affect companies and governments dependent on the copper mining industry. Copper prices follow a time series that is non-linear, non-stationary, and which have periods that change as a result of potential growth, cyclical fluctuation and errors. Sometimes the trend and cyclical components together are referred to as a trend-cycle. In order to make predictions, it is necessary to consider the different characteristics of trend-cycle. In this paper, we study a copper price prediction method using Support Vector Regression. This work explores the potential of the Support Vector Regression with external recurrences to make predictions at 5, 10, 15, 20 and 30 days into the future in the copper closing price at the London Metal Exchanges. The best model for each forecast interval is performed using a grid search and balanced cross-validation. In experiments on real data-sets, our results obtained indicate that the parameters (C, ε, γ) of the model Support Vector Regression do not differ between the different prediction intervals. Additionally, the amount of preceding values used to make the estimates does not vary according to the predicted interval. Results show that the support vector regression model has a lower prediction error and is more robust. Our results show that the presented model is able to predict copper price volatilities near reality, being the RMSE equal or less than the 2.2% for prediction periods of 5 and 10 days.

Surface Plasmon Resonance (SPR) is an attracting property of certain transition metals when they are synthesized in nano-range giving rise to promising optical applications. However, most SPR and associated applications are limited to the noble metal nanoparticles, which limits their potential due to high production cost. We report surface plasmon resonance in copper-copper oxide core-shell quantum dots synthesized via chemical route studied by using UV-Visible spectrophotometry. Tuning of the plasmonic resonance with respect to the particle diameter is achieved by an inexpensive all chemical route. Photoluminescence measurements also support the data. This size reduction leads to remarkable changes in its optical response as compared to the bulk metal. The results point towards applications of these materials in tunable SPR based biosensors.

Mining is one of the main economic activities of several developing countries as Chile. Due to the progressive fall of the ore grades and the increasingly refractory composition of minerals, concentrating plants have increased that has led to an increase in the generation of tailings. Tailings, especially those obtained in the past, have remaining copper and other valuable species in quantities that can potentially be recovered, such as gold, silver, vanadium and rare earth elements. This transforms this abundant waste into a potential source of precious or strategic metals for secondary mining. One of the techniques of solid-liquid separation that allows the processing of solutions with low concentrations of metals corresponds to the adsorption, and more recently the biosorption, which is based on the use of biological matrices that do not constitute an environmental liability after application. Biosorption occurs as a consequence of the wide variety of active functional groups present in the different types of biomass. Bacterial, fungal, plant and algal biomasses have been described as biosorbents, mainly for the treatment of diluted and simple solutions. This work aims to recover copper from leached tailings using biomass of the red algae Gracilaria chilensis as a biosorbent. The tailing samples were taken from an abandoned deposit in the north of Chile and after an acid leaching copper was biosorbed, for which the kinetics of adsorption and the equilibrium isotherms were studied, applying the Freundlich and Langmuir models. Operational parameters such as adsorbent dose, pH and initial metal concentration were studied.

This article presents the copper ions adsorption process using an activated carbon from winemaking wastes. The pH, temperature, activated carbon amount and initial copper concentration were varied based on a full factorial 2^k experimental design. Kinetic and thermodynamic studies were also carried out. The adsorption kinetics was found follow a pseudo-second-order model. The adsorption data fit better to the Langmuir isotherm. The ANOVA demonstrated that both pH of the solution and activated carbon dosage had the greatest influence on copper adsorption. The activation energy was -32 kJ·mol^-1 suggesting that the copper adsorption is a physic-sorption process. The best fit to a linear correlation was the moving boundary equation that controls the kinetics for the adsorption copper ions onto the activated carbon. The X-ray photoelectron spectroscopy (XPS) results reveal the existence of different copper species (Cu²⁺, Cu⁺ and or Cu⁰) on the surface of the carbonaceous adsorbent after the adsorption, which could suggest a simultaneous reduction process.

Staphylococcus aureus is a causative agent of nosocomial infections and its antibiotic-resistant strains are concerning. Solutions are being explored to improve the treatment of these infections, including repositioning drugs such as statins and using nanoparticles with antimicrobial properties. This study aimed to evaluate the antimicrobial effects of simvastatin (SIM) and biologically synthesized silver nanoparticles (bio-AgNPs) in isolate form and in combination by assays of minimum inhibitory concentration (MIC), an in vitro biofilm model, and the association of antimicrobials against clinical strains of S. aureus. Bio-AgNPs showed a 53.8 ± 1.23-nm mean diameter and standard deviation, a 0.23 polydispersity index, and a −25.66 ± 2.19-mV mean potential and standard deviation. Transmission electron microscopy confirmed the formation of nanoparticles and the presence of Ag0 and AgCl. S. aureus strains were sensitive to bio-AgNPs and SIM, showing 31.88-187.5 and 74.66-149.32 μM concentrations, respectively. Our association assay showed 2.0 fractional inhibitory concentration indices (i.e., indifferent for clinical strains) and 0.32 values for the standard ATCC 29213 strain (synergy). Our biofilm inhibition assays with isolated SIM and bio-AgNPs showed decreased biofilm formation from 4× to ⅛ MICs, showing no synergism in association. These findings evince that simvastatin and bio-AgNPs at subinhibitory concentrations can serve as antimicrobial agents against S. aureus biofilm.

Recent researches indicated that metal nanoparticles which have the unique optical properties can be used to enhance the spectral response of the photovoltaic modules. Since most of the nanoparticles have enhancement effects in a specific wavelength range, improving the spectral response of the photovoltaic modules in a broadband range is crucial for their applications in imaging, energy harvesting, and optical communication. In this study, flower-like silver particles are applied to achieve the enhancement effects in a broadband range. The optical absorption of photovoltaic modules is improved in a broad wavelength range of 400~2000 nm by immobilizing flower-like silver particles onto an amorphous Si p-i-n structure, and the peak responsivity of the spectral response is enhanced by about 10 times. Theoretical investigation further elaborates that the enhancement originates from the near-field effects of silver particles due to the interaction of different parts of the flower-like silver particles. Through these studies, we demonstrate that, utilizing the subwavelength silver particles with roughness surface can achieve the spectral response of the photovoltaic modules enhanced in broadband range, which can improve the utilization efficiency of optical energy for the applications of sensing, imaging, optical communication, and energy harvesting.

This study endeavors the preparation and evaluation of Phenol Furfural Resin (PFR) from bagasse and its nanocomposites for Electrically Conductive Adhesives (ECAs) application. PFR was prepared with the furfural extracted from bagasse using modified acid digestion method. Three different formulations of PFR nanocomposites with conductive nanoparticles i.e., PFR-silver, PFR-graphite, and PFR-silver + graphite were prepared using 20-60 w/w% of fillers via impregnation method. Resultant products were characterized by FT-IR, SEM, EDS and XRD spectroscopy. Electrical conductivity was measured using four probe technique while band gap was calculated via Tauc plot. Virgin PFR has shown poor conductivity up to 2.6 × 10^-4 Scm^-1 while the highest conductivity achieved was 8.2 × 10^-1 Scm^-1 for nanocomposite constituted silver, graphite, and PFR with 40:30:20 ratios respectively. This synergism was exhibited because graphite and Ag NPs supply excellent junctions for building networks. Both tend to coalesce due to van der Waals forces and high surface energies, therefore conductive pathways numbers can be increased, and contact area can be effectively enlarged. This ternary composite has exhibited the lowest bandgap energy value i.e., 3.1 eV. Thermogravimetric temperatures T₀ and T_deg values were increased up to 120 °C and 484 °C respectively, showing significant increase in thermal stability. Therefore, the resultant nanocomposite material has good potential to be employed as ECAs in electronic industry.

This study endeavors the preparation and evaluation of Phenol Furfural Resin (PFR) from bagasse and its nanocomposites for Electrically Conductive Adhesives (ECAs) application. PFR was prepared with the furfural extracted from bagasse using modified acid digestion method. Three different formulations of PFR nanocomposites with conductive nanoparticles i.e., PFR-silver, PFR-graphite, and PFR-silver + graphite were prepared using 20-60 w/w% of fillers via impregnation method. Resultant products were characterized by FT-IR, SEM, EDS and XRD spectroscopy. Electrical conductivity was measured using four probe technique while band gap was calculated via Tauc plot. Virgin PFR has shown poor conductivity up to 2.6 × 10-4 Scm-1 while the highest conductivity achieved was 8.2 × 10-1 Scm-1 for nanocomposite constituted silver, graphite, and PFR with 40:30:20 ratios respectively. This synergism was exhibited because graphite and Ag NPs supply excellent junctions for building networks. Both tend to coalesce due to van der Waals forces and high surface energies, therefore conductive pathways numbers can be increased, and contact area can be effectively enlarged. This ternary composite has exhibited the lowest bandgap energy value i.e., 3.1 eV. Thermogravimetric temperatures T0 and Tdeg values were increased up to 120 °C and 484 °C respectively, showing significant increase in thermal stability. Therefore, the resultant nanocomposite material has good potential to be employed as ECAs in electronic industry.

Introduction: Among the many factors that may limit effective wound healing in patients with chronic ulcers, bacterial infection and poor cell recruitment are primary causes that contribute to prolonged healing. Thus, a novel strategy that aims to prevent bacterial infection within the wound, while at the same time providing structural scaffolding that promotes endogenous tissue repair, would be of great interest. Here, we developed a thermo-sensitive silver nanoparticle hydrogel composite as an antibacterial nutritional scaffold for the wound that contains all nutrients required for cell growth while preventing bacterial infection with the ability to fill up all the cavities and void areas in wounds regardless of their geometry. Methods: Silver nanoparticles (AgNPs) were synthesized by chemical reduction. After characterization, silver hydrogel nanocomposite was developed by reconstitution of collagen-based hydrogel powder in a nanoparticle suspension of varying AgNPs concentrations (200, 400, and 600 ppm). The antibacterial activity of the formulations was examined in vitro and in vivo in subcutaneous implant infected model. The wound healing efficacy of the hydrogel nanocomposite was also evaluated using a splinted wound model in rats through comparison of clinical wound measurements and histological assessments. Cytocompatibility assay and biochemical analysis of blood at the end of in vivo wound healing study were performed to evaluate the safety of formulations. Results: The synthesized nanoparticles were spherical and stable. While hydrogel alone did not show any bacterial reduction in vitro, the inhibition of bacterial growth was significant in all silver hydrogel nanocomposites compared to controls (p <0.05) and was dose-dependent, with maximum reduction observed in the 600 ppm group (4.56±0.26 LOG CFU/mL, P<0.001). All concentrations of AgNPs hydrogel composites showed significant antibacterial activity in vivo as well (P<0.0001). Treatment of splinted wounds with AgNPs hydrogel composite resulted in faster wound closure and accelerated wound re-epithelialization. The formulations were non-cytotoxic and did not differ significantly in hematological and biochemical factors from the control group in in vivo study. Conclusions: By presenting promising antibacterial and wound healing activity, silver hydrogel nanocomposite offers a safe therapeutic option that can be used as a functional scaffold for an acceleration of wound healing.

Reaction of 2-mercapto-3-phenylquinazolin-4(3H)-one (MPQ) with both 4-vinyl benzyl chloride and allyl bromide furnished the reactive heterocyclic monomers 3-phenyl-2-((4-vinylbenzyl) thio) quinazolin-4(3H)-one (PVTQ) and 2-(allylthio)-3-phenylquinazolin-4(3H)-one (APQ), respectively. Copolymerization of PVTQ monomer with styrene and methyl methacrylate in the presence of 2,2′-azobisisobutyronitrile (AIBN) afforded the copolymers PS-co-PPVTQ and PMMA-co-PPVTQ, respectively. Similarly, copolymerization of monomer APQ with styrene and methyl methacrylate (MMA) afforded the copolymers PS-co-PAPQ and PMMA-co-PAPQ, respectively. The resulted copolymers were characterized by using FT-IR, 1H-NMR and GPC techniques. Silver nanocomposites of PS, PMMA, PS-co-PPVTQ, PMMA-co-PPVTQ, PS-co-PAPQ and PMMA-co-PAPQ were synthesized by the addition of silver nitrate into the polymer solution. The reduction of silver ions into silver nanoparticles was performed in DMF and water. Thermogravimetric (TGA) analysis was used to determine the thermal stability of the copolymers and their silver nanocomposites. The X-ray diffraction (XRD) analysis indicated the amorphous structures of the co-polymers and confirmed the formation of silver nanoparticles. The antitumor and antibacterial activities were screened for the copolymers and enhanced by the formation of their silver nanocomposites. In vivo antitumor activity in Ehrlich Ascitic Carcinoma (EAC) mice model showed that PS-co-PPVTQ/Ag NPs, PMMA-co-PPVTQ/Ag NPs, and PMMA-co-PAPQ/Ag NPs displayed promising inhibitory effects against EAC and induce apoptosis against MCF-7 cells.

Clinical resistance to amikacin and other aminoglycosides is usually due to enzymatic acetylation of the antimicrobial molecule. A ubiquitous resistance enzyme among Gram-negatives is the aminoglycoside 6'-N-acetyltransferase type Ib [AAC(6')-Ib], which catalyzes acetylation using acetyl-CoA as donor substrate. Therapies that combine the antibiotic and an inhibitor of the inactivation reaction could be an alternative to treat infections caused by resistant bacteria. We had previously observed that metal ions such as Zn2+ or Cu2+ in complex with ionophores interfere with the AAC(6')-Ib-mediated inactivation of aminoglycosides and reduced resistance to susceptibility levels. Ag1+ recently attracted attention as a potentiator of aminoglycosides' action by mechanisms still in discussion. We found that silver acetate is also a robust inhibitor of the enzymatic acetylation mediated by AAC(6')-Ib in vitro. This action seems to be independent of other mechanisms, like increased production of reactive oxygen species and enhanced membrane permeability, proposed to explain the potentiation of the antibiotic effect by silver ions. The addition of this compound to aac(6')-Ib harboring Acinetobacter baumannii and Escherichia coli cultures resulted in a dramatic reduction of the resistance levels. Time-kill assays showed that the combination of silver acetate and amikacin was bactericidal and exhibited low cytotoxicity to HEK293 cells.

The aim of the study was to analyze the in ovo injection of chemically and biologically synthesized silver nano-particles (Ag NPs) using Brassica oleracea L. var capitate f. Rubra, (BOL) conjugation with L-Arginine (L-Arg) on the immune, muscle growth, survivability and hatchability of the broiler chickens. L-Arg (100 μg) conjugated with 1000 µg of Ag NPs synthesized by (BOL)-extract and L-Arg (100 μg) conjugated with 100 µg of Ag NPs chemically synthesized were injected into fertile eggs at 8d, 14d and 18d of incubation. Living embryo and hatched chicks were calculated. Survivability and hatchability were not affected by the injected dose of L-Arg (100 μg) with 1000 µg (BOL-Ag NPs) and L-Arg (100 μg) with 100 µg (C-Ag NPs) but it significantly improved when the eggs were injected on day 14 of incubation compared with those injected on days 8 or 18. Moreover, the protein expression of muscle development markers such as myogenin and myoD were significantly up-related in 14 d of incubation whereas the heat shock proteins (HSPs) such as HSP-60 and HSP-70 were significantly up-regulated in 18 d incubation. In addition, the in ovo injection on 18 d significantly increased the serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) as well the immunoglobulin (IgM) levels were increased in 14d incubation period in serum at the same concentration.

Betadine (Providone-Iodine) solution is a topically applied antiseptic, which has been used for wound care and surgery for decades for the prevention and treatment of skin and wound infections. However, several studies have documented the ineffectiveness of Betadine solution. Other topical antimicrobial dressings, including those that contain silver, have been used in the management of infected wounds. The present study was undertaken to determine if the combination of 5% Betadine solutions and silver colloidal gel (Ag-gel), is more effective than the individual materials in inhibiting the growth of both Gram negative and Gram positive bacteria. These determinations were carried out by both the colony forming unit (CFU) assay, and confocal laser scanning microscopy (CLSM). Ag-gel showed complete inhibition on all the bacteria, except Klebsiella pneumoniae CI strain while 5% Betadine concentrations did not completely kill any of the tested bacteria. However, K. pneumoniae was completely eliminated in the presence of the combination of 5% Betadine solution plus Ag-gel. Confocal laser microscopy confirmed the CFU results. Thus this study demonstrated that while the individual treatments are not effective in killing all the bacteria tested, the combination of 5% Betadine solution and Ag-gel completely kill all bacteria tested, including K. penumoniae CI.

The aim of the study was to analyze the in ovo injection of chemically and biologically synthesized silver nano-particles (Ag NPs) using Brassica oleracea L. var capitate f. Rubra, (BOL) conjugation with L-Arginine (L-Arg) on the immune, muscle growth, survivability and hatchability of the broiler chickens. L-Arg (100 μg) with 1000 µg (BOL-Ag NPs) and L-Arg (100 μg) with 100 µg (C-Ag NPs) were injected into fertile eggs at 8, 14 and 18 of incubation. Survival and hatched chicks were calculated. Survivability and hatchability were unaffected by the injected dose of L-Arg (100 μg) with 1000 µg (BOL-Ag NPs) and L-Arg (100 μg) with 100 µg (C-Ag NPs) but it significantly improved when the eggs were injected on day 14 of incubation compared with those injected on days 8 or 18. Moreover, the protein expression of muscle development markers such as myogenin and myoD were significantly up-related in 14 d incubation whereas the heat shock proteins (HSPs) such as HSP-60 and HSP-70 were significantly up-regulated in 18 d incubation. In addition, the in ovo injection on 18 d significantly increased the serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) as well the immunoglobulin (IgM) levels were increased in 14-day incubation period in serum at the same concentration. Collectively, these results indicate that injecting L-Arg (100 μg) with 1000 µg of BOL-Ag NPs or L-Arg (100 μg) with 100 µg of C-Ag NPs to eggs at day 14 after incubation could improve their hatchability, survival rate, and muscle growth marker.

An array of Ag nanowires has been prepared from a facile, templated approach on Cu(BTC) (1,3,5-benzenetricarboxylic acid) metal organic framework (MOF) micropillars. The Ag-deposited scaffolding material may be used to prepare electronic or optoelectronic devices for various applications.

Background. Nanotechnology is promising field for generating new applications. A green synthesis of nanoparticles through biological methods using plant extract have a reliable and ecofriendly approach to improve our global environment. Methods. Silver nanoparticles (AgNPs) were synthesized using aqueous extract of Anagalis arvensis L and silver nitrate and were physicochemically characterized. Results. The stability of AgNPs toward acidity, alkalinity, salinity and temperature showed that they remained stable at room temperature for more than two months. The SEM and TEM analysis of the AgNPs showed that they have a uniform spherical shape with an average size in the range of 40–78 nm. Further 1-Dibhenyl-2-Picrylhydrazl radical in Anagalis arvensis L.mediated AgNPs showed a maximum activity of 98% at concentration of 200μg/mL. Hydrogen peroxide scavenging assay in Anagalis arvensis L. mediated AgNPs showed a maximum activity of 85% at concentration of 200μg/mL. Reducing power of Anagalis arvensis L.Ag NPs exhibited a higher activity of 330 μg/mL at concentration of 200 μg/mL. These NPs have cytotoxic effects against brine shrimp (Artemia salina) nauplii with a value of 53% LD 178.04μg/mL. Conclusion. The AgNPs synthesized using Anagalis arvensis L. extract demonstrate a broad range of applications.

Many wounds are unresponsive to current available treatment techniques and therefore there is an immense need to explore suitable materials including biomaterials, which are being considered as the crucial factor to accelerate the healing cascade. In this study, we fabricated polyhydroxyalkanoate based antibacterial mats via electrospun technique. One-pot green synthesized graphene decorated silver nanoparticles (GAg) were incorporated into the fibres of poly-3 hydroxybutarate-co-12 mol% hydroxyhexanoate (P3HB-co-12mol% HHx), a co-polymer of polyhydroxyalkanoate (PHA) family which is highly biocompatible, biodegradable and flexible in nature. The synthesised PHA/GAg biomaterial was characterized by field emission scanning electron microscopy (FESEM), elemental mapping, thermogravimetric analysis (TGA), UV-visible spectroscopy (UV-vis) and Fourier transform infrared spectroscopy (FTIR). In-vitro antibacterial analysis were performed to investigate the efficacy of PHA/GAg against gram positive Staphylococcus aureus (S.aureus) strain 12600 ATCC and gram negative Escherichia coli (E.coli) strain 8739 ATCC. The results indicated that the PHA/GAg demonstrated significant reduction of Staphylococcus aureus (S.aureus strain 12600 ATCC) and Escherichia coli (E.coli strain 8739 ATCC) as compared to bare PHA or PHA-rGO in 2 hours of time. The P value (P< 0.05) was obtained by using 2 sample T-test distribution.

Metallic elements of higher economic value occurring in the mineralogy of Zimapán are Pb, Zn, Cu and Fe, said elements are sold as concentrates, which, even after processing, generally include significant concentrations of Mo, Cd, Sb, Ag and As that could recover through different leaching methods. In this work the influence of temperature was studied in the complexation of silver in the S₂O₃^2--O₂ system. Chemical and mineralogical characterization of concentrated Zn from the state of Hidalgo confirmed the presence of the silver contained in a sulfide of silver arsenic (AgAsS₂) through the techniques of Atomic Absorption Spectrophotometry (AAS), X-Ray Diffraction (XRD) and Scanning Electron Microscopy-Energy-Dispersive X-Ray Spectroscopy (SEM-EDS). The mineralogical species identified allowed the construction mineralogical species Pourbaix diagrams in the range of 298 K to 333 K, through which the Eh-pH conditions to obtain silver in solution were determined. The formation of Ag(S₂O₃)₂^3- complex was confirmed by characterizing liquors leached using the technique Infrared Spectroscopy Fourier Transform (FTIR).

In this study, the corrosion performances of ammonium copper quat (ACQ) and boric acid (BA) wood preservatives were investigated, with micronized copper quat (MCQ) and nano boron (NB) used as reference materials. In the study, Scots pine (Pinus sylvestris L.) wood samples were impregnated according to the full-cell process method with ACQ at 2.4% concentration, BA at 4% and MCQ and NB at 1%. The ACQ- and BA-impregnated samples were then impregnated for a second time using five different water-repellent materials: tall oil, linseed oil, sodium silicate, methyl hydrogen silicone and N'-N- (1, 8-Naphthalyl) hydroxylamine. Polyethylene glycol (PEG) 600 and aluminum sulfate were introduced as single impregnations in the form of homogeneous mixtures with the ACQ and BA. The corrosion properties of the impregnated and control samples, including metal weight loss (MWL) and corrosion depth, were examined. As a result, the MWL values of the ACQ-impregnated samples showed an increase compared to the control group. The MWL values of the MCQ-impregnated samples were lower than those of the samples impregnated with ACQ, whilst the MWL values of the BA-impregnated samples were higher than those of the samples impregnated with NB.

The effects of rare earth Ce on the microstructure and properties of cast pure copper were investigated through thermodynamic calculations, XRD analysis, mechanical testing, metallographic microscopy, and scanning electron microscopy (SEM). The experimental results demonstrate that the reaction between rare earth Ce and oxygen as well as sulfur in copper exhibits a significantly negative Gibbs free energy value, indicating a strong thermodynamic driving force for deoxidation and desulfurization reactions. Ce is capable of removing trace amounts of O and S from copper. Moreover, the maximum solid solubility of Ce in Cu falls within the range of 0.009% to 0.01%. Furthermore, Ce can refine columnar grains while enlarging equiaxed grains in as-cast copper.Upon addition of rare earth Ce, the tensile strength increased by 8.45%, elongation increased by 12.1%, and microhardness rose from 73.5HV to 81.2HV-an increase of 10.5%. Overall, rare earth Ce has been found to enhance both the microstructure and mechanical properties of cast pure copper.

Copper oxide nanoparticles (CuONPs) were synthesized using an eco-friendly method and their antimicrobial and biocompatibility properties were determined. The supernatant and extract of the fungus Ganoderma sessile yielded small, quasi-spherical NPs with an average size of 4.5 ± 1.9 nm and 5.2 ± 2.1 nm, respectively. CuONPs showed antimicrobial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Minimum inhibitory concentration (MIC) for E. coli and S. aureus was 15.9 µg/mL for nanoparticles (NPs) using the supernatant (CuONPs-S) and 16.5 µg/ml for NPs using the extract (CuONPs-E). Lower concentrations were required for P. aeruginosa inhibition. Ultrastructural analysis revealed the presence of the small CuONPs all through the bacterial cells. Finally, the toxicity of CuONPs was analyzed in three mammalian cell lines: hepatocytes (AML-12), macrophages (RAW 264.7) and kidney (MDCK). Low concentrations (<15 µg/ml) of CuONPs-E were non-toxic to kidney cells and macrophages, and the hepatocytes were the most susceptible to CuONPs-S. The results obtained suggest that the CuONPs synthesized using the extract of the fungus G. sessile, could be further evaluated for the treatment of superficial infectious diseases.

The first single crystal structure of the homoleptic copper (II) ML2 complex (M=Cu (II), L=curcumin) was obtained and its structure was elucidated by X-ray diffraction showing a square planar geometry. The supramolecular arrangement is supported by C-H···O interactions and the solvent (MeOH) plays an important role in stabilizing the crystal packing. The cytotoxic activity of the complex against six cancer cell lines substantially surpasses that of curcumin itself, and it is particularly selective against leukemia (K562) and human glioblastoma (U251) cell lines with similar antioxidant activity to BHT. This constitutes the first crystal structure of pristine curcumin complexed with a metal ion.

Organic Coatings have potential applications in the prevention of metal corrosion in an aqueous solution. The protective effect of SEBS coated copper corrosion in NaCl 3% solution was investigated by using electrochemical methods. The main objective of this work is to find the optimal conditions of the protocol immersion to evaluate the effects of SEBS ratio and two-immersion time on the anticorrosive behaviour of copper in 3 wt % NaCl solution in order to determine the best conditions to produce a protective SEBS film on the copper surface. Response Surface Methodology (RSM) is used as an optimization method. The study’s findings show the combination of three environmental factors that minimize corrosion rate. The Box-Behnken Design (BBD) is working perfectly for the statistical significance of the model (ANOVA test). This analysis calculates the contribution value of each parameter in changing the value of the corrosion rate (CR) in not only individual but also synergistic cases. The optimized parameters were found to be a 2.17% of SEBS ratio, 20 min of immersion 1, and 21 min of immersion 2. The electrochemical impedance spectroscopy tests confirmed the results.

Abstract Purpose Since their introduction, intrauterine devices (IUDs) have been associated with various complications. Avery rare complication is the perforation of the cervix by the strings of the IUD. Purpose of the current study is to present a novel case of cervical perforation by the strings of a copper IUD and to perform a systematic review of the literature. Materials and Methods The patient a 43-year-old attended the gynecology clinic in order to remove her copper IUD. Speculum examination revealed that both the strings of the IUD perforated the anterior lip of the cervix. Management options were offered, the patient opted for a hysteroscopic removal. We searched the electronic databases: MEDLINE, Cochrane Library,Google Scholar,EBSCO for similar cases. Results Electronic search yielded 1821 articles; 8 were selected for inclusion. Mean age of the women was 35,37±7,781, range (26-47) years. One woman (12.5%) was nulligravida;3 women were multigravida (37,5%). Seven women (87,5%) were asymptomatic. Three IUDs (37,5%) were LNG-IUS; 5 IUDs (62,5%) contained copper. Conclusions Cervical perforation by the strings of IUD is an extremely rare clinical entity. It is asymptomatic in general and in most cases the strings of the IUD may be returned back to the endocervical canal after surgical maneuvers.

Copper toxicity has been a selective pressure on the sea-ice bacteria due to its widespread occur-rence in Antarctica. Here, with a combined biochemical and metabolomic approach, the Cu2+ ad-aptation mechanisms of Antarctic bacteria were analyzed. Heavy metal resistance pattern of Pb2+ > Cu2+ > Cd2+ > Hg2+ > Zn2+ was observed. Copper treatment did increase the activity of antioxidants and enzymes, maintaining cellular redox state balance and normal cell division and growth. Metabolomics analysis demonstrated that fatty acids, amino acids, and carbohydrates played dominant roles in copper stress adaptation. The results indicated that the adaptation mechanisms of strain O5 to copper stress included protein synthesis and repair, accumulation of organic per-meable substances, up-regulation of energy metabolism, and formation of fatty acids. This study increases the resistance mechanism understanding of Antarctic strains to heavy metals in extreme environments.

There is an increasing interest in applying environmentally-friendly materials in wood protection technology. This include the use of less toxic active ingredients, as well as better fixation. This study investigates the formulation based on the combination of copper and Saqez resin on the physical and biological resistance properties of poplar wood. Samples were treated by either copper-ethanolamine (Cu/MEA) and/or Saqez resin at various treatment levels. A vacuum pressure procedure was applied. The retention, weight percent gain, water absorption, volumetric swelling, and decay resistance of the samples were then determined. The highest retention and weight percent gain were obtained at the samples treated with the combination of copper-based system and Saqez resin. Additionally, the combination of the copper and Saqez improved the physical properties and decay-resistance against white-rot fungus Trametes versicolor.

Copper smelting slag is a solution of molten oxides created during the copper smelting and refining process, and about 1.5 million tons of copper slag is generated annually in Korea. Oxides in copper smelting slag include ferrous (FeO), ferric oxide (Fe­₂O₃), silica (SiO­₂ from flux), alumina (AI₂O₃), calcia (CaO) and magnesia (MgO). Main oxides in copper slag, which iron oxide and silica, exist in the form of fayalite (2FeO·SiO₂). Since the copper smelting slag contains high content of iron, and copper and zinc. Common applications of copper smelting slag are the value added products such as abrasive tools, roofing granules, road-base construction, railroad ballast, fine aggregate in concrete, etc., as well as the some studies have attempted to recover metal values from copper slag. This research was intended to recovery Fe-Cu alloy, raw material of zinc and produce reformed slag like a blast furnace slag for blast furnace slag cement from copper slag. As a results, it was confirmed that reduction smelting by carbon at temperatures above 1400°С is possible to recover pig iron containing copper from copper smelting slag, and CaO additives in the reduction smelting assist to reduce iron oxide in the fayalite and change the chemical and mineralogical composition of the slag. Copper oxide in the slag can be easily reduced and dissolved in the molten pig iron, and zinc oxide is also reduced to a volatile zinc, which is removed from the furnace as the fumes, by carbon during reduction process. When CaO addition is above 5wt.%, acid slag has been completely transformed to calcium silicate slag and observed like blast furnace slag.

Preeclampsia (PE) is characterized by a series of clinical features such as hypertension and proteinuria associated with endothelial dysfunction and the impairment of placenta vascular endothelial integrity. This study aimed to investigate the effect of serum copper (Cu) level on some angiogenesis-related factors including vascular endothelial growth factor-A (VEGF-A), soluble Fms-like tyrosine kinase-1 (sVEGF-R1), soluble endoglin (sEng) and cerruloplasmin (Cp) in Iraqi women with preeclampsia (PE) and control pregnant women. Therefore, 60 women with PE in addition to 30 healthy pregnant women were enrolled in the study. Serum concentration of sEng, VEGF-A, sVEGF-R1, and Cu in PE group significantly increased (p<0.05) in the PE group compared with that in the control group. Increased production of antiangiogenic factors, soluble VEGF-A and sEng contribute to the pathophysiology of PE, indicating the involvement of these parameters in the angiogenic balance in patients with PE. Tests for between-subject effects showed that the circulating angiogenesis factors and Cu were significantly associated with the presence of PE. Serum Cu level was significantly correlated with VEGF- A and VEGF-R1 levels but not with sEng. Multiple regression analysis revealed that only Cp and BP can significantly predict the complications in women with PE. In conclusion, serum Cu has a role in the angiogenesis in women with PE and may be a new drug target in the prevention or treatment of PE.

Alumina dispersion-strengthened copper, Glidcop, is used widely in high-heat-load ultra-high-vacuum components for synchrotron light sources (absorbers), accelerator components (beam intercepting devices) and in nuclear power plants. Glidcop has similar thermal and electrical properties to OFE (oxygen free electrical) copper, but has superior mechanical properties, thus making it a feasible structural material; its yield and ultimate strength are equivalent to those of mild-carbon steel. The purpose of this work has been to develop a brazing technique to join Glidcop to Mo, using a commercial Cu-based alloy. The effects of the excessive diffusion of the braze along the grain boundaries on the interfacial chemistry and joint microstructure, as well as on the mechanical performance of the brazed joints, has been investigated. In order to prevent the diffusion of the braze into the Glidcop alloy, a copper barrier layer has been deposited on Glidcop by means of RF-sputtering.

The article discusses the validation process of a certain method of balancing gas contained in the pore space of rocks. The validation was based upon juxtaposition of the examination of rocks' porosity and the effects of comminution in terms of assessing the possibility of opening the pore space. The tests were carried out for six dolomite samples taken from different areas of the 'Polkowice-Sieroszowice’ copper mine in Poland. Before the rock material was ground, it was examined using the porosimetric method and subsequently subjected to the SEM analysis. After grinding, the research material was subjected to the granulometric analysis. Prior to the grinding process, the rocks' porosity fell in the range of 0.3-14.8%, while the volume of the open pores was included in the 0.01-0.06 cm3/g range. The research material was also characterized by inhomogeneous distribution of the pore volume. The grinding process was performed using an original device – the GPR analyzer. The ground samples were characterized by similar particle size distribution and mean diameters D_3.2 of about 4.0-4.5 µm. The SEM analysis revealed pores of various size and shape on the surface of the rock cores, while at the same time demonstrating lack of pores following the grinding process. The grain size distribution curves were compared with the cumulative pore volume curves of the cores before grinding. The resulting intersection points of both curves were seen as testifying to the presence of openings in the rock pores and release of the accumulated gas. The opening percentage of the pore space was associated with the coordinates of the curves' intersections. In order to confirm the argument put forward in this paper – i.e. that comminution of a rock to grains of a size comparable with the size of the rock's pores results in the release of gas contained in the pore space – the amount of gas released as a result of the comminution process was studied. The results of gas balancing demonstrated that the pore space of the investigated dolomites was filled with gas in amounts from 3.19 cm3/kg to 45.86 cm3/kg. The obtained results of the rock material comminution to grains comparable – in terms of size – to the size of the pores of investigated rocks, along with asserting the presence of gas in the pore space of the studied dolomites, were regarded as a proof that the method of balancing gas in rocks via rock comminution is correct.

CuO-ZnO-Al2O3 catalysts are designed for the low-temperature shift conversion in the process of hydrogen and ammonia synthesis gas production. The paper presents the results of research on recovery of copper and zinc from spent catalysts using pyrometallurgical and hydrometallurgical methods. Under reducing conditions, at high temperature, having appropriately selected the composition of the slag, more than 66% of copper in metallic form and about 70% of zinc in the form of ZnO can be extracted from this material. Hydrometallurgical processing of the catalysts was carried out using two leaching solutions: alkaline and acidic. Almost 62% of the zinc contained in the catalysts has been leached to the alkaline solution and about 98% of copper has been leached to the acidic solution. After the hydrometallurgical treatment of the catalysts, insoluble residue was also obtained in the form of pure ZnAl2O4. This compound can be reused to produce catalysts, or it can be processed under reducing conditions at high temperature to recover zinc. The recovery of zinc and copper from such a material is consistent with the policy of sustainable development and helps to reduce the environmental load of stored wastes.

Researchers are increasingly focusing on green synthesis methods for silver nanoparticles due to their cost-effectiveness and reduced environmental impact. In this study, we utilized an edible bird's nest (EBN), a valuable economic resource, as the primary material for synthesizing silver nanoparticles using only water as the solvent. Metabolite profiling of the EBN extract was conducted using LC-QTOF-MS in positive mode (ESI+), revealing the presence of lipids, glycosides, peptides, polysaccharides, and disaccharides. Upon the addition of silver nitrate to the aqueous EBN extract, noticeable color changes from transparent to brown indicated the successful formation of AgNPs. Subsequent characterization of these silver nanoparticles involved UV-Visible spectroscopy, which revealed an absorption peak at 421 nm. Further characterization was carried out using Field Effect Scanning Electron Microscopy (FESEM), Attenuated Total Reflectance-Fourier Infrared (ATR-FTIR) spectroscopy, and Energy Dispersive X-Ray (EDX) analysis. The involvement of phenolic agents, proteins, and amino acids in reducing the silver particles was confirmed. The synthesized nanoparticles exhibited a crystalline nature, a spherical shape, and a particle size ranging from 10 to 20 nm. The presence of elemental silver was confirmed by a strong, intense peak around 3 keV in the EDX spectrum. To assess their potential, the antibacterial properties of the silver nanoparticles against Escherichia coli and Staphylococcus aureus were evaluated using the agar diffusion method.

Background: Antibiofilm activity of silver nanoparticles has been extensively investigated in common bacteria. Metallo-β-lactamase producing Gram-negative bacteria are hard-to-treat microorganisms with few therapeutic options, and silver nanoparticles were not evaluated on the biofilm of these bacteria. Objectives: The aim of this study was to evaluate the antibiofilm activity of a bone scaffold impregnated with silver nanoparticles in NDM-producing Gram-negative bacilli. Methods: Bone scaffolds from bovine femur were used for the tests and impregnated with silver nanoparticles (50 nm) by physical adsorption. Silver nitrate minimal inhibitory and bactericidal concentrations (MIC and MBC) were performed on NDM-producing Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Disc diffusion tests for silver nanoparticles susceptibility and quantification of biofilm production on plate and bone with sessile cell count were performed. Results: The MIC results demonstrated that silver nitrate had an antimicrobial effect on all microorganisms, inactivating the growth of isolates from a concentration of 8 µg/mL. MBC results showed that E. coli 16.211 was the only isolate to present MIC different from MBC, with a value of 16 µg/mL. Conclusion: Bone scaffolds impregnated with silver nanoparticles can significantly reduce biofilm, and it can be a strategic material to be used as an implant for different approaches.

Silver nanoparticles from Origanum vulgare (Oregano) have been synthesized in the past. However, no investigation has been performed on the combined effects of independent factors that affect the synthesis. Silver nitrate and Oregano concentrations, incubation temperature and time, as well as pH can play crucial roles in synthesis. In this regard Full Factorial Design was applied. A Voigt function was fitted on the measured UV – Vis spectra. The fitting parameters of the Voigt function (peak wavelength, area, and Full Width at Half Maximum) were used as the responses. A quadratic model was fitted for the peak wavelength and area, and the pH proved the dominant factor on nanoparticle synthesis.

In this contribution, time course studies were performed toward oxidation of different peroxidase substrates in the presence of silver nanozymes. In this regard, two common peroxidase substrates, TMB and DAB, were selected as model chromogens. The process of the oxidation reaction was probed by recording the absorbance of the colored products using UV-Vis spectrophotometer. Thereafter, the nanozymatic activity was calculated and used as an index for comparing the performance of the silver nanozymes against different substrates in a certain reaction time. The time course curves, revealed that the maximal activity of the silver nanozymes were achieved after a very short time of 3.0 min toward TMB oxidation while regarding DAB, the maximal activity was observed after 25.0 min which is 6.5-fold slower than that of the TMB oxidation. The difference between the DAB and TMB can be assigned to their different reaction pathways and different reactivity. In fact, the oxidation of DAB has occurred via n-electron irreversible pathway while the TMB oxidation has occurred through a simple 2-electon reversible pathway. Besides, DAB is a high stable and less relative compound compared of TMB, resulting different oxidation times, different affinity for binding to nanozyme active nodes which lead to different nanozymatic activities.

The production of nanoparticles enhances the bioactivity of biological molecules for drug delivery to infection sites. This study explains how silver nanoparticles (AgNPs) coating enhanced the hypoglycemic effects of vanillic acid in male diabetic rats with diabetes brought on by streptozotocin. (STZ). Four groups of 24 rats were created for the investigation and divided into them. The first group rats (G1; untreated) were given a basal diet, whereas the other three groups all developed diabetes through STZ injection. Diabetic rats who were not getting therapy were included in the second group (G2; STZ-positive), whereas the other diabetic rats were divided into the third group (G3, vanillic acid-treated) and the fourth group (G4; AgNPs-coated vanillic acid treated). The treatment lasted four weeks. In G2, the induction of diabetes led to an increase in serum glucose, glycated proteins, renal indices, interleukin-6 (IL-6), K+, immunoglobulins, and lipid peroxidation, while decreased Ca++, Na+, and other antioxidants in the kidney tissue homogenate. In addition, aberrant signs were present in the pancreas and kidneys of diabetic rats. The renal and pancreatic tissues were effectively enhanced by vanillic acid or vanillic acid-coated AgNPs, bringing them very close to their pre-diabetic conditions. AgNPs-coated vanillic acid offered a stronger defense against STZ-induced diabetes and lessened the effects of hyperglycemia compared to ordinary vanillic acid. Additionally, using vanillic acid coated with silver nanoparticles greatly reduced inflammation when compared to using vanillic acid alone. This outcome suggests increased antioxidant activity.

Scutellaria multicaulis, a member of the Lamiaceae, is a medicinal plant indigenous to Iran, Afghanistan, and Pakistan. It has been widely used as a prominent herb in traditional medicine for thousands of years. This plant is reported with baicalein, wogonin, and chrysin flavonoids as a significant group of chemical ingredients, which can cure different diseases such as breast cancer. S. multicaulis leave extract was used for the bioreduction of silver nanoparticles (SmL-Ag-NPs), and their phytochemical contents and antioxidant, antibacterial, anti-proliferative, and apoptotic activity were evaluated. Optimal physicochemical properties of SmL-Ag-NPs were obtained by mixing 5% of leave extract and 2 mM of aqueous AgNO3 solution and confirmed by characterization studies including UV–visible spectrophotometry, FE-SEM, EDX, DLS, zeta potential, TGA, SERS, XRD and FTIR Spectroscopy. SmL-Ag-NPs exhibited higher content of TPC (Total Phenolic Content) and TFC (Total Flavonoid Content) and potential antioxidant activity. SmL-Ag-NPs also demonstrated dose-dependent cytotoxicity against MDA-MB231 cells multiplication with an IC50 value of 37.62 μg/mL at 48h through inducing cell apoptosis. This is the first report on the biosynthesis of silver nanoparticles using S. multicaulis leave extract, which can provide treatment for cancer diseases and reduce some negative effects of chemotherapy.

Abstract composite silver nanoparticles were synthesised using melanin broth and Arabic gum as a reducing and binding agent. The reactions are carried out with water because it is a non-hazardous solvent. The produced composites either had specified diameters (average diameter of 50 nm) with high silver loading or lower loading composites with tuneable morphologies and electrical properties. UV-IR, gamma, and conventional light are used to characterise the synthesised composite silver nanoparticles. Furthermore, measurements are carried out of the dielectric constant, refractive index, energy gap, optical and electrical conductivities, and refractive index coefficients. The silver nanoparticle formation was validated by UV-Vis measurement of the sample, which demonstrated a distinct peak at a wavelength of 420 nm. The characteristics of the composite silver nanoparticles are also quantified using several methods, including XRD, SEM, and particle size analysis.

Diabetes is a life-threatening disease and chronic diabetes affects the parts of the body including the liver, kidney and pancreas. The root cause of diabetes is mainly associated with oxidative stress produced by reactive oxygen species. The minocycline is a polyphenolic drug with excellent antioxidant activities. The objective of the present study was to investigate the antidiabetic potential of minocycline modified silver nanoparticles (Mino/AgNPs) against alloxan-induced diabetic mice. The Mino/AgNPs were synthesized using minocycline as reducing and stabilizing agents. UV-vis, FTIR, X-ray diffraction (XRD) and transmission electron microscopy (TEM) were applied for the characterization of Mino/AgNPs. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay was conducted to determine the antioxidant potential of newly synthesized Mino/AgNPs. The results revealed that the Mino/AgNPs showed higher radical scavenging activity (IC50 = 19.7 µg/mL) as compared to the minocycline (IC50 = 26.0 µg/mL) and ascorbic acid (IC50 = 25.2 µg/mL). Further, the Mino/AgNPs were successfully employed to examine their antidiabetic potential against Alloxan-induced diabetic mice. Hematological results showed that the mice treated with Mino/AgNPs demonstrated a significant decrease in fasting blood glucose level and lipid profile as compared to the diabetic group. The histopathological examination confirmed that the diabetic mice treated with Mino/AgNPs showed significant recovery and revival of histo-morphology of kidney, central vein of liver and islet cells of the pancreas compared to the diabetic mice. Hence Mino/AgNPs have good antidiabetic potential and could be an appropriate nanomedicine to prevent the development of diabetes.

This work emphasizes to use silver decorative method to enhance the antibacterial activity of TiO₂ and ZnO nanoparticles. These silver decorated nanoparticles (hybrid nanoparticles) were synthesized by using sodium borohydride as a reducing agent, with the weight ratio of Ag precursors: oxide nanoparticles = 1: 30. The morphology and optical property of these hybrid nanoparticles were investigated using transmission electron microscopy (TEM) and UV–vis spectroscopy. The agar-well diffusion method was used to evaluate their antibacterial activity against both Staphylococcus aureus and Escherichia coli bacteria, with or without light irradiation. The TEM images indicated clearly that silver nanoparticles (AgNPs, 5-10 nm) were well deposited on the surface of nano-TiO₂ particles (30-60 nm). Besides, smaller AgNPs (< 2 nm) were dispersed on the surface of nano-ZnO particles (20-50 nm). UV-vis spectra confirmed that the hybridization of Ag and oxide nanoparticles led to shift the absorption edge of oxide nanoparticles to the lower energy region (visible region). The antibacterial tests indicated that both oxide pure nanoparticles did not exhibit inhibitory against bacteria, with or without light irradiation. However, the presence of AgNPs in their hybrids, even at low content (< 40 mg/mL) leads to a good antibacterial activity and the higher inhibition zones under light irradiation as compared to that in dark was observed.

Metal nanoparticle has been reported to have a high antimicrobial activity against fungi, bacteria, and yeasts. In this study, silver nanoparticles (AgNPs) were synthesized using a chemical reduction method, at 90 oC, and used as an antifungal coating in paper packaging, to control the growth of C. gloeosporioides in cut orchid flowers during shipping. AgNPs were characterized by UV-Vis spectroscopy and atomic force microscope (AFM). The results indicated that the shape of AgNPs was spherical and homogenous with an average size of 47 nm. Twenty and 50 particles per million (ppm) concentration of AgNPs, mixed with starch, were prepared as the coating solution. The paper coated with 50 ppm AgNPs exhibited a significant antifungal activity against C. gloeosporioides compared to 20 ppm AgNPs coating. The AgNPs coated paper had a better water resistance and mechanical properties compared to paper without coating. We observed a significant reduction in the number of anthers, of orchid inflorescences, infected by C. gloeosporioides, when stored in the coated boxes. The current study demonstrates that paper boxes coated with AgNPs are a potential solution to control the infection of C. gloeosporioides in the storage of cut orchid flowers.

Silver nanoparticles (AgNPs) have been demonstrated to restrain bacterial growth while maintaining the minimal risk in development of bacterial resistance and human cell toxicity that conventional silver compounds exhibit. Several physical and chemical methods have been reported to synthesize AgNPs. However, these methods are expensive and involve heavy chemical reduction agents. An alternative approach to produce AgNPs in a cost-effective and environmentally friendly way employs a biological pathway using various plant extracts to reduce metal ions. The size control issue and the stability of nanoparticles remain some of the latest challenges in such methods. In this study, we used two different concentrations of fresh leaf extract of the plant Arbutus Unedo (LEA) as a reducing and stabilizing agent to produce two size variations of AgNPs. UV-Vis spectroscopy, Dynamic Light Scattering, Transmission Electron Microscopy and zeta potential were applied for the characterization of AgNPs. Both AgNP variations were evaluated for their antibacterial efficacy against the gram-negative species Escherichia coli and Pseudomonas aeruginosa, as well as the gram-positive species Bacillus subtilis and Staphylococcus epidermidis. Although significant differences have been achieved in the nanoparticles’ size by varying the plant extract concentration during synthesis, the antibacterial effect was almost similar.

The present study aimed to investigate the effect of cold deformation on the precipitation kinetics of a binary CuSc alloy containing 0.4 wt.% scandium using the experimental analysis method of differential scanning calorimetry (DSC). Non-deformed and 75% cross-section reduced cold-rolled, supersaturated specimens were tested at non-isothermal DSC runs at up to five different heating rates. The DSC results showed that cold deformation significantly accelerated the precipitation process in the binary alloy, leading to a decrease in the initial and peak temperatures of the exothermic reactions. The activation energies calculated with the Kissinger method, indicated that the precipitation activation energy decreased with increasing cold deformation. The findings of this study provide worthy implications to further optimize the processing of Cu-Sc alloys with improved mechanical properties.

Polypyrrole (PPy)-capped caped silver nanowire (Ag NW) nanomaterials (core–shell rod-shaped Ag NW@PPy) were synthesized suing a one–port suspension polymerization technique. The thickness of PPy layer on the 50-nm-thickness/15-μm-length Ag NW was effectively controlled to 10, 40, 50, and 60 nm. Thin films cast from one-dimensional conductive Ag NW@PPy formed a three-dimensional (3-D) conductive porous network structure and provided excellent electrochemical performance. The 3-D Ag NW@PPy network can significantly reduce the internal resistance of the electrode and maintain structural stability. As a result, a high specific capacitance of 625 F/g at a scan rate of 1 mV/s was obtained from the 3-D porous Ag NW@PPy composite film. The cycling performance over a long period exceeding 10,000 cycles was also evaluated. We expect that our core–shell-structured Ag NW@PPy composites and their 3-D porous structure network films can be applied as electrochemical materials for the design and manufacture of supercapacitors and other energy storage devices.

Nanofibers are one of the most attractive materials that can modify functionalities for developing new kinds of specific applications, mainly used as a biomedical material. Herein, we designed and prepared the antibacterial nonwoven fiber mats of PLA and PLA composited with Ag nanoparticles by electrospinning. The effects of varying filler contents on their chemical, surface morphology, thermal, water absorbency, and antibacterial properties were investigated using FTIR, SEM/EDS, DSC, swelling ratio, and qualitative and quantitative antibacterial tests. FTIR and EDS spectra indicated that Ag nanoparticles were incorporated in the PLA without chemical bonding. SEM revealed that the average diameter of the PLA nanofibers containing the Ag nanoparticles was more significant than those without those particles. Besides, fiber diameters are proportionally the amount of Ag nanoparticle contents. DSC indicated that the Ag nanoparticles can be incorporated within the PLA-matrix without strongly affecting their thermal properties. Moreover, the crystallinity of the composite nonwoven fiber mats was higher than those of fiber mats in the neat PLA. Accordingly, the antibacterial activities revealed that all the composite nanofiber mats exhibited excellent against S. aureus and E. coli bacterial strains. In addition, in the cell toxicity study, all produced hybrids nonwoven fiber mats induced a reduction in cell viability for the L929 fibroblast cells. Our results suggest that the designed and prepared nonwoven fiber mats may have good potential for use in the biomedical field, particularly in wound dressing applications

A new one-pot technique for preparation of polysaccharide-based Pd- and Pd-Ag nanocatalysts by sequential supporting natural polymer (2-hydroxyethyl cellulose (HEC), chitosan (Chit), pectin (Pec)) and metals on zinc oxide was developed. The nanocatalysts based on polysaccharide were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), infrared spectroscopy (IRS), X-ray powder diffraction (XRD), X-ray photoelectron spectra (XPS) and elemental analysis methods. The catalyst characterization results indicated complete adsorption of polysaccharide and metal ions on zinc oxide, forming polymer-stabilized Pd nanoparticles of ~2 nm in size, evenly distributed on the support surface. The catalysts were studied in the hydrogenation of 2-hexyn-1-ol under mild conditions (0.1 MPa, 40 °C). The catalysts demonstrated nearly the same conversion of 2-hexyn-1-ol. The selectivity to cis-hexen-1-ol of the catalysts decreases in the following order: 0.5%Pd-Ag(3:1)HEC/ZnO>0.5%Pd-Ag(3:1)Pec/ZnO>0.5%Pd-Ag(3:1)Chit/ZnO. The optimum reaction temperature and catalyst loading for the Pd-Ag catalysts modified with HEC and Chit have been determined (40 °C, 0.05 g).

Nanoparticles (NPs) have uniform chemical composition, size, and morphology. Microorganisms are of great interest in Nanoparticle synthesis. The green production of nanomaterials occurs either intracellularly or extracellularly. Gold and silver nanoparticles are mostly synthesised by the enzymatic degradation of metal ions. The produced NPs are characterized by different instruments such as ultraviolet visible, dynamic light scattering, x-ray diffraction, scanning electron microscope, transmission electron microscope, etc. Our review discusses the various biomedical applications of gold and silver nanoparticles synthesized by microbes via intracellular and extracellular mechanisms.

The Computational theoretical techniques using first principle which make use of the density functional theory as implemented by quantum expresso as well as inter – atomic force constant (IFC) techniques (Born-von Jarman) were used to investigate the phonon dispersion curves of Silver (Ag) and Gold (Au) The results obtained show that for Au, the extension to 1 – 6^th neighbour gave slightly close agreement with the experimental phonon dispersions when compared to the 1 – 5^th neighbor at W_T and L_L symmetry points. The percentage error for Au at W_T are 2.5% and 2.9% ; at point L_L we obtained 0.6% and 0.7% respectively. The Local density Approximation (LDA) results for Ag underestimates the lattice with about 1.6% while the Generalized Gradient Approximation (GGA) overestimates it by 1.9%.

Present study reports the green synthesis of pectin fabricated silver-based nanocomposite (Pectin-AgNPs) with Carpesiumnepalense leaves extract and evaluated their bactericidal kinetics, in-vivo hepatoprotective and cytotoxic potentials with their possible mechanisms. GC/MS and LC/MS analysis indicated the presence of different new phytochemicals constituents in the plant extract. The physicochemical characterization of Pectin-AgNPs by UV/Vis, SEM, DLS, FTIR and EDX techniques showed the spherical and uniform size range synthesis of nanocomposite i.e. 50-110 nm. The highly significant (P<0.005) antibacterial activity was found against all tested four bacterial strains with the ZIs of 24.8 to 27.2 mm. Significant damage in bacterial cell membrane was also observed in AFM study after treated with Pectin-AgNPs. At the doses of 0.05 mg/kg, nanocomposite showed highly significant (P<0.005)hepatoprotective activity in biochemical and histopathology analysis as compared to CCL4 administered control group. The ameliorative effects of Pectin-AgNPs were observed in PCR analysis on both GAPDH and PPARs genes expression and its potential to restore gene alterations caused by CCl4 intoxication.Pectin-AgNPs produced cytotoxic activity against HeLa cell lines at higher doses with the LC50 of 223.7 µg/mL. The current findings demonstrate positive attributes of pectin fabricated AgNPs as a promising antibacterial, hepatoprotective and cytotoxic agent.

Two antimicrobial agents such as silver nanoparticles (AgNPs) and titanium dioxide (TiO2) have been formulated with natural polysaccharides (chitosan or alginate) to develop innovative inks for the rapid, customizable, and extremely accurate manufacturing of 3D printed scaffolds useful as dressings in the treatment of infected skin wounds. Suitable chemical-physical properties for the applicability of these innovative devices were demonstrated through the evaluation of water content (88-93%), mechanical strength (Young’s modulus 0.23-0.6 MPa), elasticity, and morphology. The antimicrobial tests performed against Staphylococcus Aureus and Pseudomonas Aeruginosa demonstrated the antimicrobial activities against Gram+ and Gram– bacteria of AgNPs and TiO2 agents embedded in the CH or ALG macroporous 3D hydrogels (AgNPs MIC starting from 5 µg/ml). The biocompatibility of chitosan was widely demonstrated by cell viability tests and was higher than that observed for alginate. Constructs containing AgNPs at 10 µg/ml concentration level did not significantly alter cell viability as well as the presence of titanium dioxide; cytotoxicity towards human fibroblasts was observed starting with AgNPs concentration of 100 µg/ml. In conclusions, the 3D printed dressings here developed own the features to be cheap, highly defined, easy to be manufactured and further applied in personalized antimicrobial medicine applications.

The carbon-carbon cross-coupling of phenyl s-tetrazine (Tz) units at their ortho-phenyl positions allows to form constrained bis(tetrazines) with original tweezer structures. In these compounds, the face-to-face positioning of the central tetrazine cores is endorsed by pi-staking of the electron-poor nitrogen-containing heteroaromatic moieties. The resulting tetra-aromatic structure can be used as a weak coordinating ligand with cationic silver. This coordination generates a set of bis(tetrazine)‐silver(I) coordination complexes tolerating a large variety of counter anions of various geometries, namely, PF6–, BF4–, SbF6–, ClO4–, NTf2–, OTf2–. These compounds were characterized in the solid-state by single crystal XRD and reflectance spectra, and in solution by 1H NMR, mass spectrometry, electroanalysis and UV-visible absorption spectroscopy. The X-ray diffraction (XRD) structure of complexes {[Ag(3)][PF6]}∞ (4) and {[Ag(3)][SbF6]∞ (6), where 3 is 3,3'-[(1,1'-biphenyl)-2,2'-diyl]-6,6'-bis[phenyl]-1,2,4,5-tetrazine, revealed the formation of 1D polymeric chains, characterized by an evolution to a large opening of the original tweezer and a coordination of silver(I) via two chelating nitrogen atom and some C=C pi-interactions. Electrochemical and UV spectroscopic properties of the original tweezer and of the corresponding silver complex are reported and compared. 1H NMR titrations with AgNTf2 allowed to determine the stoichiometry, and apparent stability of two solution species, namely [Ag(3)]+ and [Ag(3)2]2+, that formed in CDCl3/CD3OD 2:1 v/v mixtures.

Among various metal-based nanoparticles, silver nanoparticles (AgNPs) manifest superior inhibitory effect against several microorganisms. In fact, the AgNPs based therapy has been reported to inhibit both sensitive as well resistant isolates of bacteria and other disease causing microbes with equal propensity. Keeping this fact into consideration, we executed bio-mediated synthesis of AgNPs employing Hibiscus rosa sinensis flower extract. The as-synthesized AgNPs were evaluated for their potential to inhibit Streptococcus mutans (S. mutans), one of the main causative bacteria for dental caries. Beside several other reasons, orthodontic appliances have also been reported to facilitate infliction of oral cavity with a range of microbes including S. mutans. To determine the growth inhibitory and anti-adherence activity of AgNPs on orthodontic appliance, we performed microbiological assays employing AgNPs adsorbed on to the orthodontic wires. Topographic analysis of orthodontic wires was executed by scanning electron microscopy. In addition to antimicrobial and antibiofilm activity against oral S. mutans, the as-fabricated AgNPs demonstrated significant inhibitory and anti-biofilm properties against other biofilm forming bacteria such as Escherichia coli and Listeria monocytogenes as well.

There is an increasing clinical need to develop novel biomaterials that combine regenerative and biocidal properties. In this work, we present the preparation of silver /silica based glassy bioactive (ABG) compositions via a facile, fast (20h), and low temperature (80 °C) approach and their characterization. The fabrication process included the synthesis of the bioactive glass (BG) particles followed by the surface modification of the bioactive glass with silver nanoparticles. The microstructural features of ABG samples before and after exposure to simulated body fluid (SBF) as well as their ion release behavior during SBF test were evaluated using infrared spectrometry (FTIR), ultraviolet- visible (UV-Vis) spectroscopy, X-ray diffraction (XRD), electron microscopies (TEM and SEM) and optical emission spectroscopy (OES). The antibacterial properties of the experimental compositions were tested against Escherichia coli (E. coli). The results indicated that the prepared ABG materials possess antibacterial activity against E. coli, which is directly correlated with the glass surface modification.

The commercial oxygen-free copper sheets were cold-rolled with reduction rates ranging from 20% to 87% reduction rate and annealed at 400, 500 and 600 °C. The microstructure and texture evolution during cold-rolling and annealing processes were studied using optical microscopy (OM), the scanning electron microscopy (SEM) and the electron back-scattered diffraction (EBSD). The results show that the deformation textures of {123} (S) , {112} (Copper) and {110} (Brass) were continuously enhanced with the increase of cold-rolling reduction. The orientations along the α-oriented fiber converged towards Brass and the orientation density of β fiber obviously increased when the rolling reduction exceeded 60%. The recrystallization texture was significantly affected by the cold-rolling reduction. After 60% cold-rolling reduction, Copper and S textures components gradually decreased and {011} recrystallization texture component formed with the increase of annealing temperature. After 87% cold-rolling reduction, a strong Cube texture formed and other textures were inhibited with the increase of annealing temperature. The strong Brass and S deformation texture was conducive to the formation of a strong Cube annealing texture. The density of annealing twin boundary decreased with the increase of annealing temperature, and more annealing twin boundaries formed in the oxygen-free copper sheets with the increase of cold rolling reduction.

The dopamine and uric acid are primary products of purine metabolism and they coexist in serum and the extracellular fluid of the central nervous system. Some diseases of the human body are due to abnormal levels of uric acid and dopamine. Thus, the clinical diagnosis of some diseases needs a sensitive and simultaneous analysis of uric acid and dopamine. In this study, a novel conductive composite film containing multi-walled carbon nanotubes (MWTs) with cooper phthalocyanine attached to acrylate polymer (MWCNTs-CuMAPC-PnBA) was fabricated and dropped on a glassy carbon electrode and used for the simultaneous determination of Uric Acid (UA) and dopamine (DA). The modified glassy carbon electrode showed satisfactory electrocatalytic activity toward dopamine and uric acid. Low detection limits were achieved at 0.174 µM of DA and 6.87 µM of UA and the linear detection ranges of DA and UA are 5-200 µM and 20-250 µM respectively. The proposed sensing system based on the modified GCE offers promising results for rapid, cost-effective and selective simultaneous detection of uric acid and dopamine. Also, the complex modified electrode showed satisfactory results to detecting simultaneously UA and DA in real human samples (human Urine) via the standard addition method.

Aryl chlorides and bromides in the presence of NHC palladium hydroxo dimers of the type [{Pd(µ-OH)Cl(NHC)}2] (where NHC = IPr, SIPr, IMes, SIMes) undergo an efficient and selective Sonogashira cross-coupling with terminal acetylenes. For the coupling of 4-chlorotoluene with phenylacetylene TON = 560000 was observed. The procedure enables high-throughput and selective synthesis of a broad spectrum of unsymmetrically substituted 1,2-diarylacetylenes. Nearly a quantitative amount of HCl was detected within cross-coupling products. Water plays the role of the base and is regenerated in the process so that it does not have to be used in stoichiometric amounts (relative to the limiting reactant). Generation of the active Pd(0) complex proceeds via ethanol oxidation.

The depletion of the ore reserves in the world necessitates the search for secondary sources such as waste products (tailings and slag). A smelter in Namibia has historic slag which accumulated over decades of its operating life. Analytical and mineralogical characterization of the slag was performed using the X-ray fluorescence (XRF) analysis, Atomic Absorption Spectrometer (AAS), ICP-OES, scanning electron microscopy energy dispersive spectroscopy (SEM-EDS) analysis, and optical microscopy analysis. The chemical analyses showed that the metal values contained in the slag were mainly copper, lead, and zinc whose average contents were approximately 0.3%Cu, 2.4%Pb and 3.2%Zn. About 10.5%Fe was also contained in the slag. Germanium was detected by scanning electron microscopy, but was however below detection limits of the chemical analysis equipment used. Based on the results, approximate conditions under which the different slag phases were formed were estimated and the recovery routes for the various metals were proposed. Analysis by both optical and scanning electron microscopy revealed that Zn and Fe occurred mainly in association with O as oxides, while Cu and Pb were mainly associated with S as sulphides. The slag consisted of three different phases; namely the silicate phase (slag), metallic phase and the sulphide phases. The slag phases were mainly glass, silicate phases and metallic and sulphide phases. It was observed that the metallic and sulphide phases were dominant in the finer size fractions (-75 µm) whereas the sulphide phase was also present in the coarser size fractions (+300 µm). An important finding from the microscopy examination was that the sulphide phases were interstitial and could be liberated from the slag. This finding meant that liberation and subsequent concentration of the sulphide phases was feasible using conventional processing techniques.

The one pot hydrogenolysis/hydrogenation reaction of maltose to 2 moles of sorbitol has been carried out over different supported Cu catalysts in water at 180°C and 40 bar of H2. Only the catalysts supported on silicas were found to be effective in this reaction giving up to 86% yield in the desired product while the bare supports and the catalysts supported on alumina or silica alumina gave messy reactions. The peculiar activity of the two Cu/Silica systems tested was ascribed to high metal dispersion and suitable polarity of the catalyst surface. The reduced catalyst, exposing metallic Cu particles on the surface, showed unusual stability in the presence of water as a solvent and could be reused several times without any treatment.

In this investigation, Cu-Ni alloys for possible fixed dental prostheses (FDPs), with different aluminum additions were produced using vacuum atmosphere. Annealed alloys (He atmosphere) with low aluminum concentration showed a coarse dendritic structure, while samples with high aluminum concentration showed a refined dendritic structure. Structural defects analyses have shown a relative low vacancy concentrations. Hardness value increases approximately five times for the alloyed samples compared with the as-cast and unalloyed samples. Compression test results have shown a noticeable strengthening improvement, mainly in samples heat treated with 10 at % Al, while samples with 5 at % Al presented also acceptable resistance. Results are discussed in terms of dislocation mobility and hardening precipitation mechanism.

Copper nitride (Cu3N), a metastable semiconductor material, but with reasonably-high-stability at room temperature, is drawing a great deal of attention as a very promising next-generation, earth-abundant, thin-film solar absorber. Its non-toxicity, on the other hand, makes it a very attractive eco-friendly semiconducting material. In the present work, Cu3N thin films were grown by employing radio-frequency magnetron sputtering, at room temperature, with 50-W RF-power, and partial nitrogen pressures of 8.0 and 1.0, onto glass substrates. Thus, the influence of argon on the optical properties of the Cu3N thin films was studied, with the goal of being able to achieve a low-cost, light absorber material, with appropriate properties in order to substitute the more conventional silicon, in photovoltaic cells. Variable-angle spectroscopic ellipsometry measurements have been conducted at three angles, 50∘, 60∘, and 70∘, respectively, in order to obtain the two ellipsometric parameters psi, ψ, and delta, Δ, respectively. For the constructed optical model, the bulk planar Cu3N layer is described by a one-dimensional graded-index model, combine with the mixture of a Tauc-Lorentz oscillator and up to four Gaussian oscillators, whereas a BEMA model with 50%-air-void is adopted in order to account for the existing surface-roughness layer. In addition, the optical properties such as the energy-band gap, and refractive index and absorption coefficient, were determined in order to assess the actual capability of this material as a light absorber for solar cells. The direct and indirect band gap energies were accurately calculated, and they were found to be in the ranges of 2.14-2.21 eV and very clse to 1.50 eV, respectively.