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The synthetic indigo used to dye denim fades rapidly under sunlight, so improving lightfastness is important. Previously approaches were taken separately on different natural-dyed cotton by increasing the dye's concentration and applying synthetic antioxidants to improve the lightfastness of dyed samples. Little study was done to enhance lightfastness on cotton dyed using natural indigo and woad dye with different reducing agents, applying natural antioxidant and increasing the dye concentration. So, this study focuses on improving the lightfastness of indigo and woad dyed cotton instead of using synthetic indigo dye for sustainable textile coloration along with fructose as a natural and thiourea as synthetic reducing agent, varying dye concentration from 3 to 7 g/l and applying natural antioxidants lemon's raw juice after dyeing. FTIR analysis was done to confirm the presence of lemon's raw juice after treatment. Delta E was used as a lightfastness parameter instead of using a grey scale rating for quantitative analysis. From the lightfastness results, lemon-treated and using 3 g/l dye concentration dyed samples most of the cases showed better lightfastness results along with a low color fading rate than untreated dyed samples. Besides, samples using thiourea dioxide have better lightfastness properties than samples using fructose. Further statistical analysis (i.e., bootstrapping for resampling) was also done to validate these results and those statistical models confirmed those decisions. [ABSTRACT FROM AUTHOR]

As the scaling down of semiconductor devices reaches its physical limits, 3D stacking packaging technology is emerging as a new miniaturization solution. Among the various 3D packaging technologies, Cu direct bonding is widely adopted due to copper's excellent electrical conductivity and the absence of intermetallic compounds for solder bumps. Since copper readily undergoes oxidation, technologies that prevent Cu surface oxidation during Cu direct bonding are essential. However, current research suggests that the methods require additional pretreatment processes, which demand high costs. In this study, a Cu direct bonding method utilizing glycerol vapor is developed to effectively streamline the pretreatment steps. The potential of glycerol as a reducing agent and antioxidant for Cu is demonstrated using a silicon die sample with a size of 10  ×  10 mm2, verified through the X‐ray photoelectron spectroscopy. The Cu direct bonding for 3D semiconductor packaging is successfully performed under glycerol vapor atmosphere, without any plasma pretreatment. The cross‐section of the bonded specimens is examined by scanning electron microscopy, and mechanical reliability is assessed by die shear testing. [ABSTRACT FROM AUTHOR]

Almost 90% of the leather produced globally uses basic chromium sulfate (BCS) as a tanning agent for permanent stabilization of collagen protein that is produced by reducing hexavalent chromium into trivalent chromium using either organic or inorganic reducing agents. Even though organic reduction using molasses paves a greenway toward BCS manufacture, the quantum of molasses available is insufficient for BCS production to meet global needs. On the other hand, India generates approximately 500 million tonnes of agricultural waste every year, majorly comprising crop residues of rice and wheat that are burned every year to battle surplus amounts of waste. Herein, we report a new method for BCS production using polysaccharide-rich wheat bran (WB) as a reducing agent, making it a facile method to tackle molasses non-availability and burning surplus crop residues. The offer level of WB required for BCS production was optimized to match BIS norms, and the prepared product was evaluated as a tanning agent in leather production. The mechanism of chromium reduction by WB studied using IR and NMR techniques revealed polysaccharide oxidation into aldehyde and carboxylic acid following a classic redox reaction. Additionally, a method for the synthesis of metal complexes of definite morphology using agro-industrial wastes as templates is also proposed in this work. The calculated product cost also confirmed that using WB as a reducing agent in BCS production is economically feasible. [ABSTRACT FROM AUTHOR]

Copyright of Mining & Metallurgical Engineering is the property of Mining & Metallurgical Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The biosynthesis of novel nanoparticles with varied morphologies, which has good implications for their biological capabilities, has attracted increasing attention in the field of nanotechnology. Bioactive compounds present in the extract of fungi, bacteria, plants and algae are responsible for nanoparticle synthesis. In comparison to other biological resources, brown seaweeds can also be useful to convert metal ions to metal nanoparticles because of the presence of richer bioactive chemicals. Carbohydrates, proteins, polysaccharides, vitamins, enzymes, pigments, and secondary metabolites in brown seaweeds act as natural reducing, capping, and stabilizing agents in the nanoparticle's synthesis. There are around 2000 species of seaweed that dominate marine resources, but only a few have been reported for nanoparticle synthesis. The presence of bioactive chemicals in the biosynthesized metal nanoparticles confers biological activity. The biosynthesized metal and non-metal nanoparticles from brown seaweeds possess different biological activities because of their different physiochemical properties. Compared with terrestrial resources, marine resources are not much explored for nanoparticle synthesis. To confirm their morphology, characterization methods are used, such as absorption spectrophotometer, X-ray diffraction, Fourier transforms infrared spectroscopy, scanning electron microscope, and transmission electron microscopy. This review attempts to include the vital role of brown seaweed in the synthesis of metal and non-metal nanoparticles, as well as the method of synthesis and biological applications such as anticancer, antibacterial, antioxidant, anti-diabetic, and other functions. [ABSTRACT FROM AUTHOR]

The interaction between Pt nanoparticles and their supports, and the Pt nanoparticle size influence the performance and stability of Pt catalysts. Polyaniline (PANI) serves as an effective support for Pt catalysts owing to its abundant functional groups and high electron conductivity. Strong chemical interactions exist between the Pt nanoparticles and the functional groups on PANI. In this study, through the use of different reducing agents, the sizes of Pt nanoparticles on PANI nanofibers are adjusted, resulting in the preparation of three Pt/PANI catalysts. Owing to the strong reducibility of sodium borohydride, its use as a reducing agent leads to rapid heterogeneous nucleation, and the obtained Pt/PANI catalyst exhibits the smallest Pt nanoparticle size among the three Pt/PANI catalysts. Consequently, many Pt nanoparticles are not deposited on the PANI nanofibers, which reduces the activity of the Pt/PANI catalyst. Conversely, when ethylene glycol is used as the reducing agent, the resulting catalyst exhibits the largest Pt nanoparticle size among the three Pt/PANI catalysts owing to the slow reduction rate of Pt4+. The Pt/PANI catalyst prepared using formic acid (Pt/PANI-FA) achieves an optimal reaction rate owing to the moderate reducibility of the reducing agent. Consequently, the Pt nanoparticles on PANI nanofibers in Pt/PANI-FA have a diameter of 3.32 nm, which is comparable to that of Pt nanoparticles in Pt/C catalysts. The half-wave potential of Pt/PANI-FA in the oxygen reduction reaction reaches 840 mV (vs. reversible hydrogen electrode), which surpasses the 801 mV achieved by Pt/C catalysts. [Display omitted] • Polyaniline nanofiber is used as Pt support to prepared three Pt/PANI catalysts. • The size of Pt nanoparticles is tuned by using three different reducing agents. • Compared to sodium borohydride and ethylene glycol, formic acid has optimized reducibility. • The half-wave potential of optimized Pt/PANI catalyst is 840 mV, higher than that of Pt/C. • Chemical interaction between Pt and PANI improves the Pt/PANI catalyst performance. [ABSTRACT FROM AUTHOR]

Enormous advances have been made in the synthesis of metal nanoparticles (NPs) affording a high degree of control over their size, shape, and composition. In recent years, a growing effort has been dedicated to incorporating principles of green chemistry in different aspects of NPs, ranging from reagents/solvents to their fate in the environment. In this report, we focus on the use of Cyrene (dihydrolevoglucosenone) as an alternative green solvent for the synthesis of metal NPs. We begin with the synthesis of Ag NPs, given their prominence in the literature. Through control reactions, we show that Cyrene has a dual role of solvent and reducing agent. Additionally, the conversion yield for the Ag NPs synthesis was studied with respect to temperature and the Ag precursor. We then expand on the synthetic methodology to access Pd, Pt, and Bi NPs. The functionality of the synthesized NPs is assessed by employing them as electrocatalysts for furfural reduction and the hydrogen evolution reaction. We envision the use of Cyrene as a green solvent can be extended toward the synthesis of NPs of other metals and classes of materials. [ABSTRACT FROM AUTHOR]

The present study aims to evaluate the use of cranberry bush fruit pomace (CBFP) (Viburnum opulus L.), which has recently become popular raw material, as a substrate in the presence of a reducing agent to increase biobutanol production by Clostridium beijerinckii DSMZ 6422. For this purpose, some factors were optimized, including the pretreatment, initial concentration of CBFP (5–20%), different types of reducing agents (ascorbic acid, L-cysteine, sodium dithionite and sodium sulfite), different concentrations of sodium dithionite (2.5–15 mM), inoculum concentration (5%, 10%, and 20%), and fermentation time (24–96 h). The maximum biobutanol, total ABE, biobutanol yield, and biobutanol productivity were 9.45 g/L, 12.08 g/L, 0.21 g/g, and 0.13 g/L/h in the medium containing enzymatically hydrolyzed 10% CBFP, 10 mM sodium dithionite, and 20% inoculum at the end of 72 h, respectively. These findings demonstrate that CBFP can be considered as a sustainable, economical, and viable substrate on biobutanol production for the first time in the literature. [ABSTRACT FROM AUTHOR]

The steel industry accounts, according to the International Energy Agency, for ~6.7% of global CO2 emissions, and the major portion of its contribution is from steelmaking via the blast furnace (BF) route. In the short term, a significant reduction in fossil CO2 emissions can be achieved through the introduction of bio-coal into the BF as part of cold bonded briquettes, by injection, or as part of coke. The use of bio-coal-containing residue briquettes was previously demonstrated in industrial trials in Sweden, whereas bio-coal injection was only tested on a pilot scale or in one-tuyere tests. Therefore, industrial trials replacing part of the pulverized coal (PC) were conducted. It was concluded that the grinding, conveying, and injection of up to 10% of charcoal (CC) with PC can be safely achieved without negative impacts on PC injection plant or BF operational conditions and without losses of CC with the dust. From a process point of view, higher addition is possible, but it must be verified that grinding and conveying is feasible. Through an experimentally validated computational fluid flow model, it was shown that a high moisture content and the presence of oversized particles delay devolatilization and ignition, lowering the combustion efficiency. By using CC with similar heating value to PC, compositional variations in the injected blend are not critical. [ABSTRACT FROM AUTHOR]

Abstract In this work, a new ALD process for palladium metal thin films using dichlorobis(triethylphosphine)palladium(II) (PdCl2(PEt3)2) and 1,4‐bis(trimethylsilyl)‐1,4‐dihydropyrazine ((Me3Si)2DHP) as reactants, is developed. The metal precursor is chosen based on the known reactivity of metal halides with the DHP‐type reducing agents. Metallic Pd films are deposited at temperatures of 140–180 °C with a growth rate of 0.3–0.4 Å cycle−1. Furthermore using 1,4‐bis(trimethylgermyl)‐1,4‐dihydropyrazine ((Me3Ge)2DHP) as the co‐reactant yielded Pd2Ge thin films. Finally, full recyclability of the PdCl2(PEt3)2 is observed: unused molecules condensed in the exhaust tube can be collected by dissolving them into acetone, purified by recrystallization, and reused.

Abstract Surface-enhanced Raman scattering (SERS) exploits localized surface plasmon resonances in metallic nanostructures to significantly amplify Raman signals and perform ultrasensitive analyses. A critical factor for SERS-based analysis systems is the formation of numerous electromagnetic hot spots within the nanostructures, which represent regions with highly concentrated fields emerging from excited localized surface plasmons. These intense hotspot fields can amplify the Raman signal by several orders of magnitude, facilitating analyte detection at extremely low concentrations and highly sensitive molecular identification at the single-nanoparticle level. In this study, mesoscopic star-shaped gold particles (gold mesostars) were synthesized using a three-step seed-mediated growth approach coupled with the addition of silver ions. Our study confirms the successful synthesis of gold mesostars with numerous sharp tips via the multi-directional growth effect induced by the underpotential deposition of silver adatoms (AgUPD) onto the gold surfaces. The AgUPD process affects the nanocrystal growth kinetics of the noble metal and its morphological evolution, thereby leading to intricate nanostructures with high-index facets and protruding tips or branches. Mesoscopic gold particles with a distinctive star-like morphology featuring multiple sharp projections from the central core were synthesized by exploiting this phenomenon. Sharp tips of the gold mesostars facilitate intense localized electromagnetic fields, which result in strong SERS enhancements at the single-particle level. Electromagnetic fields can be further enhanced by interparticle hot spots in addition to the intraparticle local field enhancements when arranged in multilayered arrays on substrates, rendering these arrays as highly efficient SERS-active substrates with improved sensitivity. Evaluation using Raman-tagged analytes revealed a higher SERS signal intensity compared to that of individual mesostars because of interparticle hot spots enhancements. These substrates enabled analyte detection at a concentration of 10− 9 M, demonstrating their remarkable sensitivity for trace analysis applications.

Silver nanoparticles (AgNPs) have gained significant attention in various applications due to their unique properties that differ from bulk or macro-sized counterparts. In the advancement of nanotechnology, a reliable, non-toxic, and eco-friendly green synthesis has widely been developed as an alternative method for the production of AgNPs, overcoming limitations associated with the traditional physical and chemical methods. Green synthesis of AgNPs involves the utilization of biological sources including plant extracts with silver salt as the precursor. The potential of phytochemicals in plant extracts serves as a reducing/capping and stabilizing agent to aid in the bio-reduction of Ag+ ions into a stable nanoform, Ag0. This review provides insights into the potentials of various plant parts like root, stem, leaf, flower, fruit, and seed extracts that have been extensively reported for the synthesis of AgNPs. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) exploits localized surface plasmon resonances in metallic nanostructures to significantly amplify Raman signals and perform ultrasensitive analyses. A critical factor for SERS-based analysis systems is the formation of numerous electromagnetic hot spots within the nanostructures, which represent regions with highly concentrated fields emerging from excited localized surface plasmons. These intense hotspot fields can amplify the Raman signal by several orders of magnitude, facilitating analyte detection at extremely low concentrations and highly sensitive molecular identification at the single-nanoparticle level. In this study, mesoscopic star-shaped gold particles (gold mesostars) were synthesized using a three-step seed-mediated growth approach coupled with the addition of silver ions. Our study confirms the successful synthesis of gold mesostars with numerous sharp tips via the multi-directional growth effect induced by the underpotential deposition of silver adatoms (AgUPD) onto the gold surfaces. The AgUPD process affects the nanocrystal growth kinetics of the noble metal and its morphological evolution, thereby leading to intricate nanostructures with high-index facets and protruding tips or branches. Mesoscopic gold particles with a distinctive star-like morphology featuring multiple sharp projections from the central core were synthesized by exploiting this phenomenon. Sharp tips of the gold mesostars facilitate intense localized electromagnetic fields, which result in strong SERS enhancements at the single-particle level. Electromagnetic fields can be further enhanced by interparticle hot spots in addition to the intraparticle local field enhancements when arranged in multilayered arrays on substrates, rendering these arrays as highly efficient SERS-active substrates with improved sensitivity. Evaluation using Raman-tagged analytes revealed a higher SERS signal intensity compared to that of individual mesostars because of interparticle hot spots enhancements. These substrates enabled analyte detection at a concentration of 10− 9 M, demonstrating their remarkable sensitivity for trace analysis applications. [ABSTRACT FROM AUTHOR]

This study demonstrated the green synthesis route of silver (Ag), nickel (Ni), and silver-nickel bimetallic nanoparticles (Ag-Ni BNPs) using Mallotus oppositifolius leaf extract and their antimicrobial activity against bacteria and fungi. The capping ability of the leaf extract was explored and several analytical techniques confirmed the nanoparticles' biosynthesis. The antimicrobial activity of the nanoparticles was evaluated by the agar diffusion method. Optical property revealed colour change from colourless silver nitrate to brown for silver nanoparticles, the bright green of nickel chloride to dark reddish brown for nickel nanoparticles and brown for the silver-nickel nanoparticles after treatment with the extract of M. oppositifolius. FTIR showed the chemical functionalities of the possible molecules responsible for the bio-reduction of the metals. Secondary metabolites such as terpenoids, polyols, alkaloids, phenolic acids, and proteins (containing hydroxyl, aromatic amine, carbonyl groups, etc.) are present in plant extracts, and they play a crucial role in the biosynthesis of metal-based nanoparticles. UV-visible spectroscopy revealed surface plasmon resonance (SPR) at 454, 420, and 437 nm. SEM image revealed AgNPs and NiNPs nanoclusters and well-defined and less agglomerated morphology of Ag-Ni BNPs, respectively. Preliminary antimicrobial studies showed that the bimetallic nanoparticles (Ag-Ni BNPs) exhibited better antibacterial activity than their monometallic forms (AgNPs and NiNPs) but were not as effective against fungi. These findings urge future research into this hybrid material as a practical countermeasure to microbial contamination. [ABSTRACT FROM AUTHOR]

The economic advantages of H2SO4 make it the acid of choice for the hydrometallurgical treatment of waste lithium-ion batteries (LIBs). However, to facilitate the full dissolution of the higher valency metal oxides present in the cathode black mass, a suitable reducing agent is required. Herein, the application of industrial black liquor (BL) obtained from the Kraft pulping for papermaking is investigated as a renewable reducing agent for the enhanced leaching of transition metals from LIB powder with H2SO4. The addition of acidified BL to H2SO4 significantly improved the leaching efficiency for a range of LIB cathode chemistries, with the strongest effect observed for manganese-rich active material. Focusing on NMC111 (LiMnxCoyNizO2) material, a linear correlation between the BL concentration and the leaching yield of Mn was obtained, with the best overall leaching efficiencies being achieved for 2.0 molL-1 H2SO4 and 50 vol% of BL at 353 K. A quasi-total degradation of oxygenated and aromatic groups from the BL during NMC111 dissolution was observed after leaching, suggesting that these chemical groups are essential for LIB reduction. Finally, the leached transition metals could be easily recovered by pH adjustment and oxalic acid addition, closing the resource loop and fostering resource efficiency. [ABSTRACT FROM AUTHOR]

Biomass and biowastes stand as sustainable and cost-effective environmentally benign alternative feedstock. Chitosan is a biocompatible, bioactive, and biodegradable biopolymer derived from chitin to achieve eight aspects out of the 12 green chemistry principles. Chitosan got significant attention in several fields including chemical analysis, in addition to chemical functionally, which enabled its use as adsorbent and its structural crosslinking using various crosslinkers. The physicochemical, technological, and optical properties of chitosan have been extensively exploited in analysis. Mainly, deacetylation degree and molecular weight are controlling its properties and hence controlling its functions. This review presents a structure, properties, and functions relationships of chitosan. It also aims to provide an overview of the different functions that chitosan can serve in each analytical technique such as supporting matrix, catalyst...etc. The contribution of chitosan in improving the ecological performance is discussed in each technique. [ABSTRACT FROM AUTHOR]

In the field of stone conservation, the removal of iron stains is one of the most challenging issues due to the stability and low solubility of the ferrous species. In the present paper, three different chitosan-based hydrogels added with acetic, oxalic or citric acids are applied on different lithotypes, i.e., granite, travertine and marble, widely diffused in monumental heritages, and artificially stained by deposition of a rust dispersion. The reducing power of carboxylic acids is combined with the good chelating properties of chitosan to effectively remove rust from stone surfaces. As evidenced by colorimetry on three samples of each lithotype and confirmed by 1H-NMR relaxometry and SEM/EDS analyses, the chitosan-oxalic acid hydrogel shows the best performance and a single application of 24 h is enough to get a good restoration of the stone original features. Lastly, the chitosan-oxalic acid hydrogel performs well when a rusted iron grid is placed directly on the lithic surfaces to simulate a more realistic pollution. Current work in progress is devoted to finding better formulations for marble, which is the most challenging to clean or, with a different approach, to developing protective agents to prevent rust deposition. [ABSTRACT FROM AUTHOR]

To separate platinum from other impurity elements, ammonium chloride was used to selectively precipitate platinum in the state of ammonium chloroplatinate from the tail solution containing different platinum compounds. And then ammonium chloroplatinate was reduced via a liquid phase chemical reduction method to produce ultrafine platinum powder. The effects of chemical species of the intermediate, the concentration of (NH4)2PtCl6 solution, the type and amount of dispersants on the particle size, specific surface area and morphology of platinum powder were investigated. The results show that the morphology and particle size of the obtained platinum powder are not affected by the type of the tail solutions, and the average particle size of the powder prepared under the optimized conditions is about 150 nm and the purity is 99.99%. Therefore, the method developed in this study can be used for directly preparing ultrafine platinum powder from the tail liquid from the production process of various platinum compounds. [ABSTRACT FROM AUTHOR]

In this study, silver nanoparticles (AgNPs) were synthesized by utilizing different volumes of silver nitrate (AgNO3) and a medicinally important protein, bovine serum albumin (BSA); subsequently, their anticancer and antibacterial activities were investigated. The volume of AgNO3 and BSA were varied to obtain physically and chemically stable NPs for better therapeutic effects. The synthesized BSA@AgNPs were characterized by spectroscopic and microscopic methods, such as FTIR, and UV–Vis spectroscopy, SEM/EDS, and TEM/SAED. The characterization results offer substantial proof for the successful preparation of non-aggregated stable BSA@AgNPs. The EDS analysis revealed the presence of Ag, C, and O, thus reaffirming the preparation of BSA-conjugated AgNPs. The anticancer efficacy of BSA@AgNPs was studied against colorectal (HCT-116) and HeLa cancerous cell lines. The anticancer results showed that the treatment of cancer cells with BSA@AgNPs decreased the number of cells compared with untreated cells. The NPs prepared with a moderate amount of BSA showed a better inhibiting property than the particles prepared with a high amount of BSA. The antibacterial activity of BSA@AgNPs was studied against gram-positive (S. aureus) and gram-negative (E. coli) bacteria. SEM and TEM analyses confirmed that S. aureus and E. coli cells were damaged upon exposure to BSA@AgNPs in the form of deep pits and cavities as opposed to untreated cells. The obtained results show that the green synthesized BSA@AgNPs could be used as potential anticancer and antibacterial drugs.

Abstract In drilling operations, the formation of a filter cake is crucial for well stability, but its removal post-drilling is essential to restore rock formation productivity. This study focuses on hematite-based filter cakes and investigates factors influencing their solubility and removal, addressing a significant knowledge gap in the field. The research methodology involves examining the effects of various factors, including types and concentrations of reducing agents, temperature, particle size, and treatment duration, on the dissolution process. Notably, Nuclear Magnetic Resonance (NMR) tests are employed to assess the treatment's impact on core porosity. Among the diverse reducing agents examined, ferrous chloride emerges as the optimal choice for effectively enhancing hematite solubility. Particularly, a composite solution of ferrous chloride (10 wt.%) and hydrochloric acid (6 wt.%), was highly efficient demonstrated by exhibiting rapid solubilization of hematite filter cakes. A removal efficiency of approximately 99%, with a parallel enhancement in core permeability was achieved. NMR tests reveal the treatment's success in reinstating the porosity system, which had undergone reduction due to drilling fluid particles. Crucially, the solution exhibits a considerably lower corrosion rate than concentrated hydrochloric acid, highlighting its potential to mitigate environmental concerns while ensuring efficient filter cake removal. The findings of this research provide valuable insights into optimizing post-drilling operations, balancing environmental sustainability and operational efficiency. The identified composite solution offers a promising approach to efficient filter cake removal while mitigating environmental concerns associated with corrosion. Overall, this study contributes to advancing the understanding and practice of well productivity enhancement in the oil and gas industry.

This is an article in the field of mining engineering. The effects of reducing agent and dephosphorization agent on the direct reduction of high phosphorus oolitic hematite were reviewed. The research status of the influence of reducing agents on the reduction of high-phosphorus oolitic hematite was summarized from two aspects of coal and other reducing agents, and the research progress of dephosphorizers was summarized from two ways of using single and combined dephosphorizers. The problems existing in the direct reduction-magnetic separation process of high-phosphorus oolitic hematite were pointed out. According to the existing problems, suggestions for the future research direction of direct reduction-magnetic separation of high-phosphorus oolitic hematite were put forward.

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Silver-based nanomaterials have proven interesting and promising material for numerous applications such as biosensor, antimicrobial, anticancer agent, catalyst, food and water treatment, energy storage devices etc.In this study, nanoparticles of Silver and Copper were prepared by chemical reduction method, using hydrazine hydrate and Sodium borohydride as reducing agent. Fine powder of Ag-Cu nanoparticles (NPs)was obtained. The structural analysis of the sample wasdone using Powder XRD, SEM and TEM images and particle size analysis by DLS.The chemical purity and the elemental compositions of synthesized NPs were studied using SEM-EDX. Optical properties of the Ag-Cu NPs were analyzed using UV-DRS spectrum and FTIR spectrum. PXRD reveals that the NPs are highly crystalline in nature.The average crystallite size is30 nm. SEM and TEM images confirm the spherical morphology and the particle size is in nm. The DLS-particle size analyzer shows the size distribution of most of the NPs ranging from 9 nm to 100 nm. The EDX analysis reveals the percentage of elemental composition as 14.71, 9.06 and 76.23 for silver, copper and oxygen respectively. UV-DRS spectrum shows the absorption maximum occur at 371 nm. Due to the synergistic effect of silver and copper, there is blue shift in the absorption maximum. The IR spectrum discloses the metal oxide bond in the synthesized NPs.

Biosynthesized silver nanoparticles (Ag NPs) hold tremendous promise in nano-bioscience, with applications spanning engineering, science, and industry. This study delves into their fabrication process, crystallographic characteristics, and nanostructures. Employing green banana peel extract (GBPE), Ag NPs were synthesized. Various analytical techniques, such as UV–Vis absorption spectrophotometry (UV), X-ray diffraction (XRD), Gas chromatography-mass spectrometry (GC-MS), Field emission scanning electron microscopy (FESEM), Fourier-transform infrared spectroscopy (FTIR), and Transmission electron microscopy (TEM) elucidate their attributes. UV–visible analysis reveals a 413 nm absorption band due to surface plasmon resonance. The Ag NPs exhibit a face-centered cubic structure with an average crystallite size of 45.87 nm. Lattice parameters and dislocation density are also determined. When tested against harmful bacteria, such as E. coli and S. epidermidis, advanced microscopy reveals a median size of particles of 55.12 nm and demonstrates their antibacterial characteristics. These environmentally benign Ag NPs also improve the efficiency of bio-electrochemical cells (BECs), opening the door to large-scale manufacturing at a reasonable cost and broadening the range of possible uses.

The peculiar physicochemical features of deep eutectic solvents (DESs), in particular their tunability, make them ideal media for various applications. Despite their ability to solubilize metal oxides, their use as rust removers from valuable substrates has not yet been thoroughly investigated. In this study, we chose three known DESs, consisting of choline chloride and acetic, oxalic or citric acid for evaluating their ability to remove corrosion products from a cellulose-based material as linen fabric and two different lithotypes, as travertine and granite. The artificial staining was achieved by placing a rusty iron grid on their surfaces. The DESs were applied by means of cellulose poultice on the linen fabrics, while on the rusted stone surfaces with a cotton swab. Macro- and microscopic observations, colorimetry and SEM/EDS analysis were employed to ascertain the cleaning effectiveness and the absence of side effects on the samples after treatment. Oxalic acid-based DES was capable of removing rust stains from both stone and cellulose-based samples, while choline chloride/citric acid DES was effective only on stone specimens. The results suggest a new practical application of DESs for the elimination of rust from lithic and cellulosic substrates of precious and artistic value. [ABSTRACT FROM AUTHOR]

Present work deals with the extraction of nanocellulose (NC) from pistachio nut shells, which is an agro-waste. NC was extracted through acid hydrolysis and characterized with respect to particle size, and morphology. Non- agglomerated hybrid NCAg was synthesized successfully because NC can act as a reducing and stabilizing agent. The as-synthesized nanocellulose silver (NCAg) hybrid was characterized using Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV–vis), high resolution transmission electron microscopy (HRTEM), and dynamic light scattering (DLS). UV-Visible spectrum at 406 nm revealed surface plasmon resonance (SPR) caused by the spherically shaped Ag-NPs. X-ray diffraction (XRD) and HRTEM studies confirmed the FCC crystalline structure of silver in the nanocellulose matrix. The Ag-NPs were uniform and spherical, with particle size ranging from 2 to 18 nm according to the TEM micrographs. NCAg hybrid was tested for antibacterial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis bacteria. The NCAg hybrid with controlled morphology, size and good antibacterial activity has potential applications in active packaging films, wound treatment, coatings, adhesives, and anti-biofouling films with good reinforcement ability. [ABSTRACT FROM AUTHOR]

By using Centella asiatica leaf extract, reduced graphene oxide (rGO) decorated PbS/CdO nanocomposite (rPC) was synthesized by reducing graphene oxide. To investigate the photocatalytic, electrochemical, and antibacterial properties of the synthesized rPC NC, different analytical techniques were employed and compared with those of the PbS/CdO NC synthesized by chemical precipitation. The XRD analysis of both samples revealed cubic structured peaks of PbS and CdO. Pb, S, Cd, O, and C can be detected from rPC's EDS spectrum. PC and rPC exhibited band gap energies of 2.28 and 2.21 eV, respectively. Both samples show FTIR peaks related to lead sulfide and Cd–O stretching vibrations. Interstitial sulfur and singly occupied oxygen vacancy peaks are evinced in the PL spectra. The PL intensity for rPC is reduced, which is indicative of low recombination rates for photogenerated e−/h+ pairs. Photodegradation efficiencies against methyl violet were 81.2 and 93.4% for PC and rPC catalysts. Electrochemical and antibacterial properties of PC improved with rGO inclusion. [ABSTRACT FROM AUTHOR]

Silver-based nanomaterials have proven interesting and promising material for numerous applications such as biosensor, antimicrobial, anticancer agent, catalyst, food and water treatment, energy storage devices etc. In this study, nanoparticles of Silver and Copper were prepared by chemical reduction method, using hydrazine hydrate and Sodium borohydride as reducing agent. Fine powder of Ag-Cu nanoparticles (NPs)was obtained. The structural analysis of the sample wasdone using Powder XRD, SEM and TEM images and particle size analysis by DLS.The chemical purity and the elemental compositions of synthesized NPs were studied using SEM-EDX. Optical properties of the Ag-Cu NPs were analyzed using UV-DRS spectrum and FTIR spectrum. PXRD reveals that the NPs are highly crystalline in nature. The average crystallite size is30 nm. SEM and TEM images confirm the spherical morphology, and the particle size is in nm. The DLS-particle size analyzer shows the size distribution of most of the NPs ranging from 9 nm to 100 nm. The EDX analysis reveals the percentage of elemental composition as 14.71, 9.06 and 76.23 for silver, copper and oxygen respectively. UV-DRS spectrum shows the absorption maximum occur at 371 nm. Due to the synergistic effect of silver and copper, there is blue shift in the absorption maximum. The IR spectrum discloses the metal oxide bond in the synthesized NPs. [ABSTRACT FROM AUTHOR]

The synthesis of gold nanoparticles (AuNPs) by bottom-up methods, such as redox reactions using amino acids and gold salts, has turned out to be a novel method for obtaining nanoparticles due to the reducing properties of these biomolecules and the ability to give the nanoparticle peculiar physicochemical characteristics for its biological application, thus derived from the known structure and amino acids functional groups. In this sense, this work shows the characterization using UV-Vis, DLS, FTIR, XPS, and HRTEM techniques of AuNPs synthesized using sodium borohydride (NaBH4) as a reducing compound and L-cysteine methyl ester hydrochloride (cysteine precursor) (HSCH2CH (NH2) COOCH3 • HCl) as a stabilizing agent. The above elucidates the reaction mechanisms for the formation of the nanoparticle through these reactions, as well as the stabilizing action and possible reducing potential of cysteine. Likewise, the resulting Cis@AuNP compounds were subjected to a preliminary biological evaluation using cell viability toxicity tests. The Cis@AuNPs showed high colloidal stability in a pH range of 3 to 11, where the L-cysteine methyl ester hydrochloride functional groups strongly influenced the hydrodynamic diameter and zeta potential behavior. Cytotoxicity assays in mouse leukocytes demonstrated the safety of these nanoparticles. These encouraging results open the way to explore the biological application potential of these systems with the perspective of their possible application in vaccinology. [ABSTRACT FROM AUTHOR]

Purpose: This paper explores a life cycle assessment (LCA) case study of two char carbon reductants for silicon alloys production, manufactured from Polish and Colombian hard coal. Life cycle assessment (LCA) of chars has not been thoroughly analysed and described in the scientific literature and the studies on high silicon alloys tend to focus solely on climate change with smaller consideration of other important environmental issues. Methods: This cradle-to-gate LCA of chars uses 1 tonne of final product as a functional unit. The method chosen for the life cycle impact assessment (LCIA) is Environmental Footprint 3.0 (EF 3.0) and five impact categories from the method were chosen for presenting environmental impacts (climate change, particulate matter, freshwater eutrophication, freshwater ecotoxicity, and fossil resource use), with remaining available in supplementary materials. Results and discussion: While the carbon footprint for char produced from Polish coal is 13% higher than for char derived from Colombian and amounts, respectively, to 1554.4 and 1373.3 kg CO2 eq, the freshwater ecotoxicity for char from Colombian coal achieving 113,956 CTUe outperforms the result of 11,749 CTUe measured for Polish char. When applying weighting aggregated into single score results, Polish and Colombian char obtained, respectively, 109.4 mPt and 160.1 mPt. Activities relating to the manufacturing stage had the largest impact on climate change and particulate matter due to the coal devolatilisation process but mining operations were most damaging to freshwater eutrophication, ecotoxicity, and fossil resource use. The paper also investigates and presents potential optimisation opportunities in the area of char production. Conclusions and recommendations: A comparative life cycle assessment of two chars fills the research gap in the literature. Results for selected impact categories of EF 3.0 method for both Polish and Colombian chars show variability of environmental loads, but clearly suggest that the greatest environmental burdens concern the coal extraction process. Most scientific literature on the metallurgy industry focuses on carbon footprint as the most important impact. While the carbon footprint of Polish char is slightly higher than that of its Colombian counterpart, other environmental impact categories can exhibit opposite trends. This is especially significant in the freshwater ecotoxicity category, which is ten times higher for Colombian char and can be attributed to the open-cast mining process. Therefore, it is important to analyse chars in terms of alternative technological solutions aimed at maintaining optimal usability in all life cycle stages, taking into account a holistic view to possibilities of reducing environmental impacts. [ABSTRACT FROM AUTHOR]

Recovery of valuable metals from used portable batteries is gaining widespread importance owing to the conservation of natural sources and possible environmental pollution from these batteries. In this paper, zinc (Zn) and manganese (Mn) recovery from waste zinc–carbon (Zn–C) batteries was investigated. For this purpose, two-stage leaching experiments were conducted in the laboratory. In the first stage, only sulfuric acid (H2SO4) solution was used, and in the second stage, ferrous ion (Fe2+) was added to the H2SO4 solution as a reducing agent. The burnt and wet sieved battery powder was obtained from manually disassembled waste Zn–C batteries. Particle size fraction of -75 + 53 µm battery powder contained 23.75% Zn and 48.47% Mn. Leaching experiments performed with a solid-to-liquid ratio of 4 g/L showed that Zn and Mn were leached with a recovery of 100% and 58.55%, respectively, using 400 rpm stirring speed, 0.25 M H2SO4 solution, and 70 °C temperature. Reductive leaching experiments showed that all of the Mn was recovered in 0.25 M H2SO4 solution using 3.6 × 10–2 M Fe2+ as a reducing agent at 60 °C temperature. [ABSTRACT FROM AUTHOR]

The steel industry accounts, according to the International Energy Agency, for ~6.7% of global CO2 emissions, and the major portion of its contribution is from steelmaking via the blast furnace (BF) route. In the short term, a significant reduction in fossil CO2 emissions can be achieved through the introduction of bio-coal into the BF as part of cold bonded briquettes, by injection, or as part of coke. The use of bio-coal-containing residue briquettes was previously demonstrated in industrial trials in Sweden, whereas bio-coal injection was only tested on a pilot scale or in one-tuyere tests. Therefore, industrial trials replacing part of the pulverized coal (PC) were conducted. It was concluded that the grinding, conveying, and injection of up to 10% of charcoal (CC) with PC can be safely achieved without negative impacts on PC injection plant or BF operational conditions and without losses of CC with the dust. From a process point of view, higher addition is possible, but it must be verified that grinding and conveying is feasible. Through an experimentally validated computational fluid flow model, it was shown that a high moisture content and the presence of oversized particles delay devolatilization and ignition, lowering the combustion efficiency. By using CC with similar heating value to PC, compositional variations in the injected blend are not critical.