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Industrial biotechnology and biocatalysis can provide very effective synthetic tools to increase the sustainability of the production of fine chemicals, especially flavour and fragrance (F&F) ingredients, the market demand of which has been constantly increasing in the last years. One of the most important transformations in F&F chemistry is the reduction of C C bonds, typically carried out with metal-catalysed hydrogenations or hydride-based reagents. Its biocatalytic counterpart is a competitive alternative, showcasing a range of advantages such as excellent chemo-, regio- and stereoselectivity, ease of implementation, mild reaction conditions and modest environmental impact. In the present review, the application of biocatalysed alkene reductions (from microbial fermentations with wild-type strains to engineered isolated ene-reductase enzymes) to synthetic processes useful for the F&F industry will be described, highlighting not only the exquisite stereoselectivity achieved, but also the overall improvement when chirality is not involved. Multi-enzymatic cascades involving C C bioreductions are also examined, which allow much greater chemical complexity to be built in one-pot biocatalytic systems. [Display omitted] • C C reduction is a key transformation in the synthesis of flavours and fragrances. • Biocatalytic alternatives involve ene-reductases or microorganisms habouring them. • Many examples of industrially relevant molecules are provided and discussed. • Multi-enzymatic systems involving C C bioreductions are also examined. [ABSTRACT FROM AUTHOR]

In the design of photoelectrocatalytic cells, a key element is effective photogeneration of electron‐hole pairs to drive redox activation of catalysts. Despite recent progress in photoelectrocatalysis, experimental realization of a high‐performance photocathode for multi‐electron reduction of chemicals, such as nitrate reduction to ammonia, has remained a challenge due to difficulty in obtaining efficient electrode configurations for extraction of high‐throughput electrons from absorbed photons. This work describes a new design for catalytic photoelectrodes using chromophore assembly‐functionalized covalent networks for boosting eight‐electron reduction of nitrate to ammonia. Upon sunlight irradiation, the photoelectrode stores a mass of reducing equivalents at the photoexcited chromophore assembly for multielectron reduction of a copper catalyst, enabling efficient nitrate reduction to ammonia. By introducing the new photoelectrode structure, it is demonstrated that the electronic interplay between charge photo‐accumulating assembly and multi‐electron redox catalysts can be optimized to achieve proper balance between electron transfer dynamics and thermodynamic output of photoelectrocatalytic systems. [ABSTRACT FROM AUTHOR]

Using KOH-modified wheat straw as the precursor, wheat straw biochar was produced through carbonization at 500 °C. Subsequently, a synthetic material containing nano-zero-valent iron (nZVI) was prepared via liquid phase reduction (nZVI-WSPC). To enhance its properties, chitosan (CTS) was used by crosslinking to form the new adsorbent named CTS@nZVI-WSPC. The impact of CTS on parameters such as mass ratio, initial pH value, and adsorbent dosage on the adsorption efficiency of Cr(VI) in solution was investigated through one-factor experiments. Isotherm adsorption and thermodynamic analysis demonstrated that the adsorption of Cr(VI) by CTS@nZVI-WSPC conforms to the Langmuir model, with a maximum adsorption capacity of 147.93 mg/g, and the adsorption process is endothermic. Kinetic analysis revealed that the adsorption process follows a pseudo-second-order kinetic model. The adsorption mechanism, as elucidated by SEM, FTIR, XPS, and XRD, suggests that the process may involve multiple mechanisms, including pore adsorption, electrostatic adsorption, chemical reduction, and surface chelation. The adsorption capacity of Cr(VI) by CTS@nZVI-WSPC remains high after five cycles. The adsorbent is simple to operate, economical, efficient, and reusable, making it a promising candidate for the treatment of Cr(VI) in water. [ABSTRACT FROM AUTHOR]

This review article is a comprehensive and current overview on chalcones, covering their sources, identification methods, and properties with a particular focus on their applications in the agricultural sector. The widespread use of synthetic pesticides has not only led to increased resistance among weeds and pests, resulting in economic losses, but it has also raised significant health concerns due to the overuse of these chemicals. In line with the European Green Deal 2030 and its Farm to Fork strategy, there is a targeted 50% reduction in the use of chemical pesticides by 2030, emphasizing a shift towards natural alternatives that are more environmentally sustainable and help in the restoration of natural resources. Chalcones and their derivatives, with their herbicidal, fungicidal, bactericidal, and antiviral properties, appear to be ideal candidates. These naturally occurring compounds have been recognized for their beneficial health effects for many years and have applications across multiple areas. This review not only complements the previous literature on the agricultural use of chalcones but also provides updates and introduces methods of detection such as chromatography and MALDI technique. [ABSTRACT FROM AUTHOR]

Borane–trimethylamine complex (Me3N·BH3; BTM) is the most stable of the amine–borane complexes that are commercially available, and it is cost-effective. It is a valuable reagent in organic chemistry with applications in the reduction of carbonyl groups and carbon–nitrogen double bond reduction, with considerable examples in the reduction of oximes, hydrazones and azines. The transfer hydrogenation of aromatic N-heterocycles and the selective N-monomethylation of primary anilines are further examples of recent applications, whereas the reduction of nitrobenzenes to anilines and the reductive deprotection of N-tritylamines are useful tools in the organic synthesis. Moreover, BTM is the main reagent in the regioselective cleavage of cyclic acetals, a reaction of great importance for carbohydrate chemistry. Recent innovative applications of BTM, such as CO2 utilization as feedstock and radical chemistry by photocatalysis, have extended their usefulness in new reactions. The present review is focused on the applications of borane–trimethylamine complex as a reagent in organic synthesis and has not been covered in previous reviews regarding amine–borane complexes. [ABSTRACT FROM AUTHOR]

Recently, aiming for the enhanced dispersibility of graphene-based nanomaterials in lubricating oil matrices to serve as highly efficient lubricant additives, numerous modification approaches have been extensively studied. However, these previous modification routes usually involve a tedious multistep modification process or multitudinous toxic reagents, restricting their extensive practical application. In this work, novel graphene oxide (GO) nanoadditives (RGO-g-BO) featuring excellent durable dispersion capability and remarkable tribological performance were successfully prepared via an environmentally friendly one-step approach consisting of surface grafting of long-chain bromooctadecane (BO) and in situ chemical reduction. Benefiting from the greatly improved lipophilicity (resulting from the introduction of hydrophobic long-chain alkane groups and chemical reduction), along with the miniaturization effect, RGO-g-BO exhibits superior long-term dispersion stability in the finished oil. Moreover, the tribological properties results demonstrated that the finished oil filled with RGO-g-BO nanolubricants achieved an outstanding friction-reducing and antiwear performance. Particularly, under the optimum content of RGO-g-BO (as low as 0.005 wt%), the friction coefficient as well as the wear volume of the composite finished oil were greatly reduced by 13% and 53%, respectively, as compared with nascent finished oil. Therefore, in view of the advantages of low-cost, one-step facile synthesis, desirable dispersion capability, and remarkable tribological performance, RGO-g-BO holds great prospects as a highly efficient lubrication additive in the tribology field. [ABSTRACT FROM AUTHOR]

Molybdenum‐ or tungsten‐dependent formate dehydrogenases have emerged as significant catalysts for the chemical reduction of CO2 to formate, with biotechnological applications envisaged in climate‐change mitigation. The role of Met405 in the active site of Desulfovibrio vulgaris formate dehydrogenase AB (DvFdhAB) has remained elusive. However, its proximity to the metal site and the conformational change that it undergoes between the resting and active forms suggests a functional role. In this work, the M405S variant was engineered, which allowed the active‐site geometry in the absence of methionine Sδ interactions with the metal site to be revealed and the role of Met405 in catalysis to be probed. This variant displayed reduced activity in both formate oxidation and CO2 reduction, together with an increased sensitivity to oxygen inactivation. [ABSTRACT FROM AUTHOR]

Asymmetric reduction of the conjugated CC bonds by the old yellow enzymes (OYEs) presents a promising field in the synthesis of chiral chemicals. Nevertheless, few natural OYEs have been applied in large-scale applications due to the requirement of costly NADPH and low operational stability. Herein, a stable and efficient fusion of YqjM from Bacillus subtilis and glucose dehydrogenase (GDH) from Bacillus megaterium was constructed to stereoselectively reduce the conjugated CC bonds in a self-sufficient continuous process. The effects of the enzyme order and different linkers on the fusions were investigated by structural analysis and all-atom molecular dynamics simulation. The best fusion YqjM_G_GDH gave 98% conversion of 100 ​mmol/L 2-methylcyclopentenone with an excellent ee value (>99%) in 3 ​h, while the mixture of individual enzymes only obtained 68% conversion after more than 8 ​h. The improved substrate conversion of YqjM_G_GDH fusion was probably attributed to the increased flexibility of each fused enzyme and the shortening of the diffusion distance of NADPH regenerated. A one-pot process was designed to purify and immobilize the fusion on the Ni2+-nitrilotriacetic acid functionalized magnetic mesoporous silica nanoflowers. The resulting immobilized biocatalyst not only catalyzed the asymmetric reduction of various α,β-unsaturated ketones (20 ​mmol/L) continuously with only 50 ​μmol/L NADP+ to initiate the whole process, but also retained more than 82% of the initial activity after seven cycles, serving as a good candidate for the industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • IrCo 0.13 nanoalloy is prepared by chemical reduction and electrochemical treatment. • Abundant Co vacancies and atomic heterostructure facilitate OER and HER. • Strong interaction of Ir and Co contributes to remarkable stability and activity. • IrCo 0.13 exhibits an overpotential of 238 (OER) and 18.6 mV (HER)@10 mA cm−2, respectively. • Bifunctional IrCo 0.13 as both anode and cathode displays 1.68 V@1 A cm−2 in PEMWE. Exploring the electrocatalysts with high intrinsic activity and stability for both anode and cathode to tolerate the extremely acidic condition in proton exchange membrane water electrolyzer (PEMWE) is crucial for widespread industrial application. Herein, we constructed the bifunctional IrCo x nanoalloys with abundant metal vacancies via the combination of chemical reduction and electrochemical treatment for overall water splitting. The developed IrCo 0.13 exhibits ultra-low overpotentials of 238 mV for OER and 18.6 mV for HER at 10 mA cm−2 in 0.1 M HClO 4 , and achieves the exceptional stability of 1000 h for OER and 100 h for HER at 10 mA cm−2. Further, the cell voltage is only 1.68 V to reach a high current density of 1 A cm−2 in PEMWE with IrCo 0.13 as the both cathode and anode catalytic layer, and it shows excellent corrosion resistance in acidic environment, evidenced by 415 h stable operation at 1 A cm−2. The strong electronic interactions in the Ir-Co atomic heterostructure and the in-situ generation of Co vacancies by electrochemical oxidation synergistically contribute to the enhanced activity and stability via optimizing the electronic structure of adjacent Ir active sites, enhancing the conductivity and electrochemical active surface area of the catalyst, accelerating charge transfer and kinetics. This work provides a new perspective for designing bifunctional catalysts for practical application in PEMWE. [ABSTRACT FROM AUTHOR]

[Display omitted] Production of C 2 chemicals (such as C 2 H 4 , C 2 H 5 OH, etc.) from CO 2 electroreduction reaction (CO 2 ER) has been regarded as a promising route to solve the environmental problems and energy crisis. In this work, mesoporous Cu 2 O microspheres of ca. 700 nm diameter size with low crystallinity were fabricated to enable efficient conversion of CO 2 to C 2 chemicals by electrocatalytic reduction. It is revealed that compared with bulk Cu 2 O, the obtained mesoporous Cu 2 O microspheres have larger surface area, more grain boundaries and defects (unsaturated coordination sites), which facilitate the adsorption and stabilization of the important intermediates, such as *CO, on the route to C 2 chemicals formation. As a result, the Faraday efficiency (FE) of C 2 products reaches as high as 82.6 % and 78.5 % in an H-cell and a flow cell, respectively. In situ Raman and FT-IR spectra reveal that during CO 2 ER test there exists abundant *CO on the mesoporous Cu 2 O surface, thus increasing the opportunity of C C coupling. And the high coverage of *CO on catalyst surface during CO 2 ER protects and stabilizes the oxidation state of Cu species. This work demonstrates an effective strategy to introduce mesoporous structures and decreased crystallinity for improving the performance of CO 2 ER to C 2 products. [ABSTRACT FROM AUTHOR]

A Cs 3 Bi 2 Br 9 @Nb 2 O 5 S-scheme photocatalyst is constructed by embedding Cs 3 Bi 2 Br 9 perovskite quantum dots into mesoporous Nb 2 O 5. Profiting from the boosted charge separation, as well as the enhanced CO 2 adsorption contributed by mesoporous Nb 2 O 5 , the Cs 3 Bi 2 Br 9 @Nb 2 O 5 nanocomposite exhibits excellent CO 2 photoreduction performance. [Display omitted] Solar-energy-powered CO 2 reduction into valuable chemical fuels represents a highly promising strategy to address the currently energy and environmental issues. Owing to the nontoxicity and robust reduction capability, lead-free Cs 3 Bi 2 Br 9 perovskite quantum dots (PQDs) are regarded as an attractive material for CO 2 photoreduction. Nevertheless, the potential of their applications in this field has been restricted by the severe charge recombination, resulting in unsatisfactory photocatalytic performance. Herein, a step-scheme-based Cs 3 Bi 2 Br 9 @Nb 2 O 5 (CBB@Nb 2 O 5) nanocomposite was fabricated by embedding the CBB PQDs into mesoporous Nb 2 O 5. Experimental studies, along with theoretical calculations, revealed that the charge migration route in the CBB@Nb 2 O 5 nanocomposite conformed to the step-scheme (S-scheme) mode, enabling effective charge separation and strong redox ability preservation. Profiting from the promoted charge separation, as well as the improved CO 2 adsorption contributed by mesoporous Nb 2 O 5 , the CBB@Nb 2 O 5 nanocomposite unveiled superior CO 2 photoreduction performance, with CO evolution rate reaching 143.63 μmol g−1h−1. The present study provides a potential strategy to manufacture highly-efficient perovskite-based photocatalysts for achieving carbon neutrality. [ABSTRACT FROM AUTHOR]

In this study, a series of cobalt-based spinel ferrites catalysts, including nickel, cobalt, zinc, and copper ferrites, were synthesized using the sol–gel auto-combustion method followed by a chemical reduction process. These catalysts were employed for accelerating hydrogen generation via the sodium borohydride hydrolysis process. A continuous stirred tank reactor was used to perform catalytic reactor tests. All samples were subjected to analysis using XRD, FESEM, EDX, FTIR, and nitrogen adsorption–desorption techniques. The results revealed that the cobalt-based copper ferrite sample, Co/Cu-Ferrite, exhibited superior particle distribution, and porosity characteristics, as it achieved a high hydrogen generation rate of 2937 mL/min.gcat. In addition, the higher electrical donating property of Cu-Ferrite which leads to the increase in the electron density of the cobalt active sites can account for its superior performance towards hydrolysis of NaBH4. Using the Arrhenius equation and the zero-order reaction calculation, activation energy for the sodium borohydride hydrolysis reaction on the Co/Cu-Ferrite catalyst was determined to be 18.12 kJ/mol. This low activation energy compared to other cobalt-based spinel ferrite catalysts confirms the catalyst's superior performance as well. Additionally, the outcomes from the recycling experiments revealed a gradual decline in the catalyst's performance after each cycle during 4 repetitive cycles. The aforementioned properties render the Co/Cu-Ferrite catalyst an efficient catalyst for hydrogen generation through NaBH4 hydrolysis. [ABSTRACT FROM AUTHOR]

[Display omitted] Although solar steam generation is promising for seawater desalination, it is less effective in purifying wastewater with both salt/heavy metal ions and organic contaminants. It is thus imperative to develop multifunctional integrated solar-driven water purification systems with high solar-thermal evaporation and photocatalytic degradation efficiencies. Herein, a lamellar reduced graphene oxide (L-RGO) foam with the vertical lamellar structure is fabricated by bidirectional-freezing, lyophilization, and slight chemical reduction for water purification. The unique vertical lamellar structure not only accelerates upward transport of water for facilitating water evaporation but also endows the L-RGO foam with superb high elasticity for tuning the interlayer distance and varying interactions between the oxygen-containing groups and water molecules to adjust water energy state. As a result, the L-RGO foam achieves a superb water evaporation rate of 2.40 kg m−2 h−1 along with an energy efficiency of 95.3 % under the compressive strain of 44.7 % under 1-sun irradiation. Equally importantly, the decoration of L-RGO foam with polypyrrole is capable of efficiently degrading organic pollutants while retaining high solar steam generation performances, exhibiting great potential in the comprehensive treatment of various water sources for relieving freshwater crisis. [ABSTRACT FROM AUTHOR]

In this work, UV-Vis spectrophotometry, High Resolution Scanning Transmission Electron Microscopes and selected experimental conditions were used to screen the colloidal system. The obtained results complement the established knowledge regarding the mechanism of nanoparticle formation. The process of gold nanoparticles formation involves a two-step reduction of Au ions to Au(0); atom association and metastable cluster formation; autocatalytic cluster growth; ultra-small particle formation (1–2 nm, in diameter); particle growth and larger particles formation; and further autocatalytic crystal growth (D > 100 nm). As a reductant of Au(III) ions, a cinnamon extract was used. It was confirmed that eugenol as one of the cinnamon extract compounds is responsible for fast Au(III) ion reduction, whereas cinnamaldehyde acts as a gold-particle stabilizer. Spectrophotometry studies were carried out to track kinetic traces of gold nanoparticle (D > 2 nm) formation in the colloidal solution. Using the Watzky—Finke model, the rate constants of nucleation and autocatalytic growth were determined. Moreover, the values of energy, enthalpy and entropy of activation for stages related to the process of nanoparticle formation (Index 1 relates to nucleation, and Index 2 relates to the growth) were determined and found to be E1 = 70.6 kJ, E2 = 19.6 kJ, ΔH1 = 67.9 kJ/mol, ΔH2 = 17 kJ/mol, ΔS1 = −76.2 J/(K·mol), ΔS2 = −204.2 J/(K·mol), respectively. In this work the limitation of each technique (spectrophotometry vs. HRSTEM) as a complex tool to understand the dynamic of the colloidal system was discussed. [ABSTRACT FROM AUTHOR]

Acanthopanax senticosus polysaccharide–nano-selenium (ASPS-SENPS) and A. selenopanax selenized polysaccharides (Se-ASPS) were synthesized, and their characterization and biological properties were compared. The acid extraction method was used to extract the polysaccharides of A. selenopanax, followed by decolorization using the hydrogen peroxide method and deproteinization based on the Sevage method, and the purification of A. senticosus polysaccharides (ASPS) was carried out using the cellulose DEAE-52 ion column layer analysis method. An A. senticosus polysaccharide–nano-selenium complex was synthesized by a chemical reduction method using ASPS as dispersants. The selenization of polysaccharides from A. selenopanax was carried out using the HNO3-Na2SeO3 method. The chemical compositions, scanning electron microscopy images, infrared spectra, and antioxidant properties of ASPS-SENPS and Se-ASPS were studied, and they were also subjected to thermogravimetric analysis. The results indicated that the optimal conditions for the synthesis of ASPS-SENPS include the following: when ASPS accounts for 10%, the ratio of ascorbic acid and sodium selenium should be 4:1, the response time should be 4 h, and the reaction temperature should be 50 °C. The most favorable conditions for the synthesis of Se-ASPS were as follows: m (Na2SeO3):m (ASPS) = 4:5, response temperature = 50 °C, and response time = 11.0 h. In the in vitro antioxidant assay, when the mass concentration of Se-ASPS and ASPS-SENPS was 5 mg/mL, the removal rates for DPPH free radicals were 88.44 ± 2.83% and 98.89 ± 3.57%, respectively, and the removal rates for ABTS free radicals were 90.11 ± 3.43% and 98.99 ± 1.73%, respectively, stronger than those for ASPS. The current study compares the physiological and bioactivity effects of ASPS-SENPS and Se-ASPS, providing a basis for future studies on polysaccharides. [ABSTRACT FROM AUTHOR]

One of the main problems in current agriculture is the reduction of chemical fertilizers by replacing them with biofertilizers composed of beneficial microorganisms for soils and plants. Therefore, the present work aims to evaluate the effect of Pseudoxanthomonas indica named H32, previously isolated from healthy tomato plants rhizosphere, on the growth, development and yield of chard, carrot and radish crops. To this end, its ability to produce indoleacetic acid (IAA) was determined. In addition, its property to solubilizing insoluble phosphate in Pikovskaya-agar medium. The seeds were inoculated by soaking in a H32 cells suspension with 105 UFC/mL in 0.1 % carboxymetyl cellulose solution, for 3 h. A similar procedure using only carboxymetyl cellulose solution was done for non-inoculated seeds. All Seeds were then sown in 1 x 10 m plots. H32 was inoculated around the root of the seedlings of inoculated seeds, seven days after germination. The results showed that plants from inoculated seeds had greater humid weight, greater height, and roots with greater length and weight than plants from non-inoculated seeds (P < 0.01). The inoculation of the seeds and soil with H32 increased the yield by 19 % for radish, 88.7 % and 68.5 % for chard and carrot, respectively. These results show that Pseudoxanthomonas indica H32 has potential for use as a growth promoter in the crops studied. [ABSTRACT FROM AUTHOR]

The endohedral lithium fulleride, Li+@C60•−, is a potential precursor for new families of molecular superconducting and electronic materials beyond those accessible to date from C60 itself. Solid Li@C60 comprises (Li@C60)2 dimers, isostructural and isoelectronic with the (C59N)2 units found in solid azafullerene. Here, we investigate the structural and vibrational properties of Li@C60 samples synthesized by electrolytic reduction routes. The resulting materials are of high quality, with crystallinity far superior to that of their antecedents isolated by chemical reduction. They permit facile, unambiguous identification of both the reduced state of the fulleride units and the interball C-C bonds responsible for dimerization. However, severe orientational disorder conceals any crystal symmetry lowering due to the presence of dimers. Diffraction reveals the adoption of a hexagonal crystal structure (space group P63/mmc) at both low temperatures and high pressures, typically associated with close-packing of spherical monomer units. Such a situation is reminiscent of the structural behavior of the high-pressure Phase I of solid dihydrogen, H2. [ABSTRACT FROM AUTHOR]

Reducing fertilizer usage is a crucial measure for achieving high-quality development in Chinese agriculture. Utilizing panel data from 31 Chinese provinces spanning from 2004 to 2019, this study empirically analyzes the dynamic relationship between fertilizer application and grain production, exploring the underlying mechanisms. The study findings reveal that the application of fertilizers maintains a positive impact on grain production. The two variables will demonstrate a dynamic alternation between "strong decoupling" and "retreat decoupling," suggesting that grain production may either increase or gradually decline, while fertilizer application exhibits a decreasing trend. Mechanism analysis reveals a distinct substitution relationship between fertilizer use efficiency and application quantity. Increasing fertilizer use efficiency while reducing application quantity still facilitates the stable and increased production of grains. Heterogeneity analysis indicates that the efficiency of fertilizer use has a more pronounced impact on grain yield in the eastern and western regions. Increasing fertilizer quantity is detrimental to wheat yield but has a promoting effect on corn yield. However, in the main grain-producing areas, increasing fertilizer quantity can enhance wheat yield but is unfavorable for the overall grain yield. Additionally, nitrogen fertilizer input has exceeded the optimal level compared to potassium fertilizer. Continuously increasing nitrogen fertilizer input will hinder the increase in grain yield. Therefore, there is a need to shift from the notion of "more fertilizer is better" and focus on improving fertilizer use efficiency to transition from the emphasis on "quantity" to "quality" of fertilizer application. [ABSTRACT FROM AUTHOR]

Durum wheat is one of the main crops in the Mediterranean region, which is characterized as the hotspot of climate change, with large year-to-year weather fluctuations. Although chemical input reduction in agriculture is strongly demanded, as well as healthy food, there is still a lack of stable and high-yielding crop varieties specifically adapted for organic conditions. This study evaluates the performance of fifteen durum wheat varieties in terms of suitability for organic farming in central Italy and assesses the impact of the genotype–environment interaction (GEI) on productive and quality traits. Variety performance was evaluated in field experiments over four successive seasons. In addition, a genotypic diversity analysis of 38 microsatellites associated with traits important for organic farming was performed. The AMMI (additive main effects and multiplicative interaction) stability analysis revealed that the best and most stable genotype regarding quality traits, such as thousand-kernel weight, protein content, and test weight was the ancient variety, Senatore Cappelli. The most stable and high yield was determined for the Fuego, Iride, and Mv-Pelsodur genotypes. Moreover, SSR markers that could be used for plant breeding, targeting organic farming systems based on molecular markers and GEI results, were identified. [ABSTRACT FROM AUTHOR]

The monitoring of low gaseous elemental mercury (GEM) concentrations in the atmosphere requires continuous high-resolution measurements and corresponding calibration capabilities. Currently, continuous calibration for GEM is still an issue at ambient concentrations (1–2 ngm-3). This paper presents a continuous flow calibration for GEM, traceable to NIST 3133 Standard Reference Material (SRM). This calibration approach was tested using a direct mercury analyser based on atomic absorption spectrometry with Zeeman background correction (Zeeman AAS). The produced continuous flow of GEM standard was obtained via the reduction of Hg2+ from liquid NIST 3133 SRM and used for the traceable calibration of the Zeeman AAS device. Measurements of atmospheric GEM using the calibrated Zeeman AAS were compared with two methods: (1) manual gold amalgamation atomic fluorescence spectrometry (AFS) calibrated with the chemical reduction of NIST 3133 and (2) automated gold amalgamation AFS calibrated using the mercury bell-jar syringe technique. The comparisons showed that a factory-calibrated Zeeman AAS device underestimates concentrations under 10 ngm-3 by up to 35 % relative to the two other methods of determination. However, when a calibration based on NIST 3133 SRM was used to perform a traceable calibration of the Zeeman AAS, the results were more comparable with other methods. The expanded relative combined uncertainty for the Zeeman AAS ranged from 8 % for measurements at the 40 ngm-3 level to 91.6 % for concentrations under 5 ngm-3 using the newly developed calibration system. High uncertainty for measurements performed under 5 ngm-3 was mainly due to instrument noise and concentration variation in the samples. [ABSTRACT FROM AUTHOR]

Conjugated polymers are promising tools to differentiate various types of semiconducting single-walled carbon nanotubes (s-SWCNTs). However, their synthesis is challenging. Insufficient control over molecular weights, and unpredictive/unrepeatable batches hinder possible applications and scale-up. Furthermore, commercial homogeneous catalysts often require inert conditions and are almost impossible to recycle. To overcome these problems, we present a nanocatalyst consisting of magnetic nickel nanowires decorated with highly active palladium nanoparticles. A two-step wet chemical reduction protocol with the assistance of sonochemistry was employed to obtain a heterogeneous catalyst capable of conducting step-growth Suzuki polycondensation of a fluorene-based monomer. Additionally, we enhanced the performance of our catalytic system via controlled microwave irradiation, which significantly shortened the reaction time from 3 d to only 1 h. We studied the influence of the main process parameters on the yield and polymer chain length to gain insight into phenomena occurring in the presence of metallic species under microwave irradiation. Finally, the produced polymers were used to extract specific s-SWCNTs by conjugated polymer extraction to validate their utility. [ABSTRACT FROM AUTHOR]

Hierarchical porous nanostructure alumina ceramics (HP-Al 2 O 3) were prepared through a novel approach involving polymer-assisted freeze-drying and subsequent calcination. The resulting material exhibits interconnected micro-meso-macro pores, distinguishing it from traditional Al 2 O 3 nanoparticles (Al 2 O 3 -Nps) prepared without freeze-drying. By manipulating freeze-drying precursors and calcination temperatures, we tailor the morphology and structure of HP-Al 2 O 3. Notably, the HP-Al 2 O 3 demonstrates a remarkable 5.3-fold increase in adsorption efficiency for Congo red compared to Al 2 O 3 -Nps, attributed to its significantly larger specific surface area. The HP-Al 2 O 3 is a versatile platform for building multi-functional composites, proved by immobilizing silver nanoparticles (AgNps) and graphitized carbonitride (g-C 3 N 4) through chemical reduction and gas-solid reaction methods, respectively. When employed for the reduction of 4-nitrophenol and the degradation of Rhodamine B, Ag/HP-Al 2 O 3 and g-C 3 N 4 /HP-Al 2 O 3 display approximately 2.5 and 2.4 times higher reaction rate constants compared to Ag/Al 2 O 3 -Nps and g-C 3 N 4 /Al 2 O 3 -Nps. This enhanced catalytic performance is attributed to several key factors: the 3D porous framework of the HP-Al 2 O 3 facilitates efficient catalyst immobilization, the microporous and mesoporous nature increases the active site and specific surface area, and the hierarchical porous structure enhances mass diffusion and light capture. Moreover, the self-supporting nature of the HP-Al 2 O 3 simplifies separation and recovery from reaction solutions. With the integration of its hierarchical porous structure and commendable recovery properties, HP-Al 2 O 3 emerges as a promising candidate for various functional applications, particularly in catalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • The carbonized recycled melamine sponge obtained excellent low-cost porous matrix. • FeNi@NCS shows lower reaction potential and higher electron transfer ability on UOR. • Successfully assembled the DBHPFC using urine as fuel. • DUHPFC presents excellent open circuit voltage. The direct urea fuel cell (DUFC) is a power generation equipment with urea-rich wastewater or urine as fuel source. It has the unique ability to purify sewage while simultaneously generating electricity, making it a highly efficient and environmentally friendly option. In this paper, pomegranate seed-like Ni nano-blocks and Fe nanosheets were synthesized by electrodeposition and chemical reduction and attached to the carbonized melamine sponge matrix. The N -doped carbon sponge (NCS) provided a large number of polyhedral holes, which allowed for efficient gas escape through channels. The combination of Fe reduces the initial urea oxidation potential, reaction activation energy and reaction resistance. The synthesized FeNi supported on N -doped carbon sponge composite (FeNi@NCS) has a catalytic current density of 625 mA cm−2 and a Tafel slope of 42.51 mV dec−1 for urea electrooxidation reaction (UOR). Assembling the direct urine-hydrogen peroxide fuel cell (DUrHPFC) resulted in the highest performance output. The open circuit voltage (OCV) was 0.98 V, and the peak power density reached 9.61 mW cm−2. The results show that the prepared catalyst provides an opportunity to solve the problems that hinder the development of urea green cycle at present. [ABSTRACT FROM AUTHOR]

[Display omitted] • Expanded vermiculite is integrated with a photoactive COF polymer. • Total Cr removal is realized by combining Cr(VI) reduction with Cr(III) exchange. • The spent catalyst is recycled for efficient ciprofloxacin and NO photooxidation. Design and fabrication of feasible remediation composites for total Cr (Cr(T)) removal is still challenging but urgently required. Herein, eco-friendly expanded vermiculite (VE) is integrated with a photoactive covalent organic framework (COF) polymer, in which photoinduced electrons of surface anchored COF can freely transfer to Cr(VI) for chemical reduction, and layered expanded VE allows ion exchange between resultant Cr(III) cations and interlayered K+, Ca2+, Mg2+, Na+, etc. The Cr(T) removal capacities of the surface-modified VE with important parameters (solution pH value, initial Cr(VI) concentration, etc.) are discussed extensively to understand how to select the best conditions for optimum Cr(T) removal performance. More interestingly, from a circular economy view point, spent Cr-loading VE-based waste can serve as a photocatalyst towards oxidation conversion of ciprofloxacin and NO gas subsequently. Explanations for different effects on physicochemical properties as well as catalytic activities of the reused Cr-loading waste are given. This strategy could provide valuable and promising contribution towards the development of sustainable low-cost mineral materials for Cr(T) removal. These findings also shed new light on the research of recycling spent photocatalyst for resource and reutilization. [ABSTRACT FROM AUTHOR]

Selenium, an essential micronutrient for plants and animals, can cause selenium toxicity as an oxyanion or at elevated doses. However, the toxic selenite (SeO32−) oxyanion, can be converted into less harmful elemental nano-selenium (Se0), with various practical applications. This research aimed to investigate two methods for reducing SeO32−: abiotic reduction using cell-free extract from Enterococcus spp. (abiotic-SeNPs) and chemical reduction involving L-ascorbic acid (chemical-SeNPs). Analysis with XPS confirmed the presence of Se0, while FTIR analysis identified surface functional groups on all SeNPs. The study evaluated the effects of SeO32−, abiotic-SeNPs, and chemical-SeNPs at different concentrations on the growth and germination of Pisum sativum L. seeds. SeO32− demonstrated detrimental effects on germination at concentrations of 1 ppm (germination index (GI) = 0.3). Conversely, both abiotic- and chemical-SeNPs had positive impacts on germination, with GI > 120 at 10 ppm. Through the DPPH assay, it was discovered that SeNPs exhibited superior antioxidant capabilities at 80 ppm, achieving over 70% inhibition, compared to SeO32− (less than 20% inhibition), therefore evidencing significant antioxidant properties. This demonstrates that SeNPs have the potential to be utilized as an agricultural fertilizer additive, benefiting seedling germination and development, while also protecting against oxidative stress. [ABSTRACT FROM AUTHOR]

In recent decades, nanoscale zero-valent iron (nZVI) has been extensively studied for application in environmental remediation because it is an eco-friendly, inexpensive nanomaterial with high reactivity. The chemical reduction of iron ions using NaBH4 in a liquid solution is the most frequently used method to obtain nZVI, but its drawbacks are the use of expensive and toxic NaBH4 and the secondary pollution caused by the B(OH)3 by-product. In this study, in order to obtain nZVI in a cleaner manner, we used a reduction method for Fe2O3 using CaH2, which is non-toxic and generates no pollutants. The results of X-ray diffraction, nitrogen adsorption, and scanning electron microscopy for the obtained samples indicated the formation of zero-valent iron nanopowder (22.5 m2/g) that was obtained via reduction at 220 °C for 5 h. The obtained nZVI was finally tested in the catalytic hydrogenation of p-nitrophenol as a model reaction of water remediation, verifying its good catalytic performance. [ABSTRACT FROM AUTHOR]

This document discusses the process of CO2 methanation, which involves converting carbon dioxide and hydrogen gases into methane and water. This reaction is important for carbon capture and utilization strategies, as it allows for the recycling of CO2 emissions into valuable methane. The document explores different catalysts and reactor types used in CO2 methanation, as well as studies on catalyst deactivation and regeneration, reactor performance prediction, plasmonic catalysts, chemical reduction methods, and fluidized-bed reactor design. The Special Issue on "Catalytic CO2 Methanation Reactors and Processes" provides valuable insights into catalyst preparation, reaction kinetics, and reactor modeling, contributing to advancements in renewable energy storage. [Extracted from the article]

Microbial biocontrol agents have emerged as a promising alternative for the management of plant diseases and the reduction of chemical pesticide dependence. However, a significant challenge in using these agents is their inconsistent performance under field conditions, often caused by the poor establishment and limited spread of microorganisms. Entomovectoring, a system where microbial biocontrol agents are dispersed to crops via pollinators, provides a potential solution to these challenges. Still, there are limited examples of successful systems, and no studies have tested this technology with versatile and generally beneficial lactobacilli. Here, we demonstrate that Lactiplantibacillus plantarum AMBP214 shows potential as a biocontrol agent displaying antimicrobial activity in an in vitro and a gnotobiotic seedling experiment, and the ability to establish itself in strawberry flowers. An innovative formulation and dispersal strategy were proven successful with this strain, as it could be formulated into a spray-dried powder that could be loaded onto bumblebees via a dispenser. When loaded bumblebees were released into a greenhouse with strawberry plants, L. plantarum AMBP214 was effectively dispersed to flowers, resulting in high bacterial abundances (on average 1 × 105 CFUs per flower) and consistent coverage across all sampled flowers. We could not show a protective effect of AMBP214 against Botrytis cinerea in a greenhouse trial with strawberry flowers under the tested conditions, so that further screening of other strains against this major pathogen will be necessary. However, our study provides the necessary proof of concept data that spray-dried lactobacilli can be used with entomovectoring, providing a novel and promising approach to biocontrol. These results pave the way for further research and development of spray-dried non-spore-forming bacteria in entomovectoring strategies, which hold great promise for enhancing plant health and mitigating the negative impacts of plant diseases. IMPORTANCE Plant protection products are essential for ensuring food production, but their use poses a threat to human and environmental health, and their efficacy is decreasing due to the acquisition of resistance by pathogens. Stricter regulations and consumer demand for cleaner produce are driving the search for safer and more sustainable alternatives. Microbial biocontrol agents, such as microorganisms with antifungal activity, have emerged as a promising alternative management strategy, but their commercial use has been limited by poor establishment and spread on crops. This study presents a novel system to overcome these challenges. The biocontrol agent Lactiplantibacillus plantarum AMBP214 was spray-dried and successfully dispersed to strawberry flowers via bumblebees. This is the first report of combining spray-dried, non-spore-forming bacteria with pollinator-dispersal, which scored better than the state-of-the-art in terms of dispersal to the plant (CFU/flower), and resuscitation of the biocontrol agent. Therefore, this new entomovectoring system holds great promise for the use of biocontrol agents for disease management in agriculture. [ABSTRACT FROM AUTHOR]

It is still challenging to avoid polyaniline agglomeration and fabricate polyaniline-based adsorbents with stable structure, excellent adsorption performance. Herein, we synthesized montmorillonite/humic acid/polyvinyl alcohol@polyaniline (MMT/HA/PVA@PANI) composite porous hydrogel adsorbent by Pickering emulsion template-in situ chemical oxidative polymerization, and the enhancement effect of this design idea on the adsorption performance of PANI was studied with heavy metal ion hexavalent chromium Cr(VI) as the target adsorbate. The in-situ polymerization of aniline at the Pickering emulsion interface and the unique three-dimensional network structure of the hydrogel act as an effective "confinement" for the growth of the polyaniline. The porous structure of hydrogel can be used as water channel, which can accelerate the combination of adsorbate and adsorption site, and significantly improve the adsorption capacity and adsorption rate. Compared with the pure PANI (43.48 mg g−1 PANI), MMT/HA/PVA@PANI (1753.60 mg g−1 PANI) obviously had significantly higher removal efficiency, which increased the removal efficiency of Cr(VI) by about 40 times. Adsorption experiments suggest that solution pH, adsorbent dosage, contact time and initial concentration all have certain effects on adsorption performance. According to the FESEM, EDX, FTIR and XPS analysis of the materials before and after adsorption, the removal of Cr(VI) is mainly enhanced by ion exchange, electrostatic attraction and chemical reduction. In conclusion, MMT/HA/PVA@PANI adsorbent has novel design, good adsorption performance and strong stability, and it has great development prospects in removing heavy metal ions from wastewater. [ABSTRACT FROM AUTHOR]

The debate between ontological reductionists and emergentists in chemistry has revolved around quantum mechanics. What Franklin and Seifert (BJPS 2020) add to the long-running dispute is an attention to the measurement problem. They contend that all three realist interpretations of the quantum formalism capable of resolving the measurement problem also obviate any need for chemical emergence. I push their argument further, arguing that the realist interpretations of quantum mechanics actually subvert the basis for reduction as well, by undercutting the idea that fundamental physical particles are actual parts of molecules. With both reduction and traditional synchronic emergence pictures ruled out, the only option for realists about quantum chemistry is strong Thomistic emergence. [ABSTRACT FROM AUTHOR]

This study demonstrated a rapid method of producing PtPd via chemical reduction by varying metal composition and types of capping agents. The effect of different compositions between the two-metal precursor, Pt and Pd, is invested by tuning at various volume ratios of 3:1, 1:3, and 1:1 and comparing them with their single counterparts. The FESEM results show that all prepared samples exhibit nanosponges structure. PtPd of 1:1 ratio has the highest ECSA of 14.25 m²/g, while PtPd with PVP exhibits a high ECSA value of 692.7 m²/g compared to those without capping agent (287.8 m²/g), indicating large active sites, which increases its catalytic function. [ABSTRACT FROM AUTHOR]

The monitoring of low gaseous elemental mercury (GEM) concentrations in the atmosphere requires continuous high-resolution measurements and corresponding calibration capabilities. Currently, continuous calibration for GEM is still an issue at ambient concentrations (1-2 ng m-3). This paper presents a continuous flow calibration for GEM, traceable to NIST 3133 Standard Reference Material (SRM). This calibration approach was tested using a direct mercury analyser based on atomic absorption spectrometry with Zeeman background correction (Zeeman AAS). The produced continuous flow of GEM standard was obtained through reduction of Hg2+ from liquid SRM NIST 3133 and used for traceable calibration of Zeeman AAS. Measurements of atmospheric GEM using the calibrated Zeeman AAS were compared with two methods: manual gold amalgamation atomic fluorescence spectrometry (AFS) calibrated with the chemical reduction of NIST 3133 and automated gold amalgamation AFS calibrated using the mercury bell-jar syringe technique. The comparisons showed that factorycalibrated Zeeman AAS underestimates concentrations under 10 ng m-3 by up to 35 % relative to the two other methods of determination. However, when a calibration based on SRM NIST 3133 was used to perform a traceable calibration of Zeeman AAS, the results were more comparable with other methods. The expanded relative combined uncertainty for Zeeman AAS ranged from 8 % for measurements at the 40 ng m-3 level to 91.6 % for concentrations under 5 ng m-3 using the newly developed calibration system. High uncertainty for measurements performed under 5 ng m-3 was due mainly to instrument noise and concentration variation in the samples. [ABSTRACT FROM AUTHOR]

The article presents the results of mechanical testing of Ni-P/Si3N4 nanocomposite and hybrid Ni-P/Si3N4/graphite coatings deposited on AW-7075 aluminum alloy using the chemical reduction method. In terms of mechanical testing, microhardness was measured, and surface roughness and adhesion of the coatings to the aluminum substrate were determined using the "scratch test" method. The surface morphology of the deposited layers was also analyzed using light microscopy and scanning electron microscopy. Samples made of AW-7075 aluminum alloy with electroless deposited Ni-P/Si3N4 nanocomposite, Ni-P/graphite composite and hybrid Ni-P/Si3N4/graphite coatings with different content of dispersed phases were tested, and also, for comparison purposes, the Ni-P layer that constituted the matrix of the tested materials. Reinforcing phases in the form of silicon nitride nanoparticles and graphite particles were used in the layers. The purpose of the research was a thorough characterization of the coating materials used on aluminum alloys in terms of mechanical properties. Graphite is considered in this paper as it enables the reduction of the coefficient of friction through its lubricating properties. Unfortunately, graphite is difficult to use in selected layers as the only dispersion phase, because it has much lower hardness than the Ni-P coating. For this reason, a layer with a single dispersion phase in the form of graphite will be characterized by worse mechanical properties. It is necessary to add particles or nanoparticles with hardness higher than the base Ni-P coating, e.g., Si3N4, which improve the mechanical properties of the coating. The presented analyses of the results of the conducted research complement the previous studies on selected properties of nanocomposite layers with an amorphous structure and supplement the knowledge regarding their suitability for application to aluminum machine parts. [ABSTRACT FROM AUTHOR]

In this work, palladium nanoparticles, supported by polyaminals (Pd@PAN-NA), were synthesized via a reverse double solvent approach and used as a nano catalyst. The thermogravimetric and the elemental analysis revealed that the catalyst had good dispersity and improved thermal stability. The catalytic activity of the prepared Pd@PAN-NA catalyst was studied for a methylene blue chemical reaction in the presence of NaBH4 as a reducing agent. The effect of the catalyst dose, pH, and dye initial concentration were examined to optimize the chemical reduction conditions. The prepared catalyst Pd@PAN-NA removed 99.8% of methylene blue organic dye, indicating its potential effect for treating waste and contaminated water. [ABSTRACT FROM AUTHOR]

Triazolo[4,3-a]pyrimidine is one of the promising structural fragments for the development of drugs, including anticancer drugs. This work is devoted to the synthesis of a number of new 2-arylhydrazone derivatives of thiazolo[3,2-a]pyrimidine, which are synthetic precursors for triazolo[4,3-a]pyrimidines. The crystal structure of 6-acetyl-7-methyl-5-phenyl-2-(2-phenylhydrazineylidene)-5H-thiazolo[3,2-a]pyrimidin-3(2H)-one was established by SCXRD. In the reduction reaction of the compound, the following system was used: vanadium(V) oxide, and sodium borohydride in ethanol at room temperature, which led to the formation of only one pair of diastereomers (1R*)-1-((5S*,6R*,7R*)-(1-(hydroxymethyl)-7-methyl-1,5-diphenyl-1,5,6,7-tetrahydro[1,2,4]triazolo[4,3-a]pyrimidin-6-yl)ethan-1-ol. [ABSTRACT FROM AUTHOR]

The development of cost-efficient electrocatalysts for oxygen evolution reaction (OER) with high efficiency is crucial to widespread applications of water splitting for hydrogen production. In this work, porous three-dimensional (3D) amorphous NiFe nanoaggregates composed of interconnected nanograins were synthesized by a cyanogel-based wet chemical reduction method using the NiCl2/Na4Fe(CN)6 cyanogel as the precursor and NaBH4 as the reducing agent. The influence of the incorporated Fe amount was carefully studied by slightly changing the feeding molar ratios of the Ni/Fe atoms in the precursors. The intrinsic 3D backbone structure of the cyanogel resulted in crystal nuclei tending to generate along with the backbones, which is key to the formation of NiFe nanoaggregates with a porous 3D interconnected structure. The synthesized NiFe nanoaggregates with a 3D interconnected structure and high porosity, as well as the incorporation of Fe, are in favor of high surface area, more active sites, and abundant oxygen vacancies, leading to superior activity and stability of OER in alkaline electrolytes with a low overpotential of 0.35 V at 10 mA cm−2, a high current density of 24.8 mA cm−2 at 1.65 V, a small Tafel slope of 76.9 mV dec−1, and attractive durability in 1 M KOH solution. [ABSTRACT FROM AUTHOR]

One of the development directions in the nanotechnology field is the synthesis of nanoparticles in the direction of green synthesis. In this study, Ag@AgCl nanoparticles were synthesized via the chemical reduction method using purple Cam leaf extract as reducing and capping/stability agents. The products were characterized by X-ray diffraction (XRD), Raman, field emission scanning electron microscope and UV–Vis techniques. The results XRD contributed to the Ag@AgCl nanoparticles were successfully synthesized with an average diameter of 15 nm. The ratio of Ag and AgCl depends on the volume of AgNO3 used. Raman spectroscopy indicates different group functions responsible for reducing agents and stabilizers in the reaction. The analysis by UV–vis spectra confirmed the formation of Ag@AgCl nanoparticles following the Lambert–Beer theorem and stabilize after 20 days. The Ag@AgCl nanoparticles exhibited the catalysis activity of decomposing red Congo, which is 6–31 times that of reaction without using catalysis. [ABSTRACT FROM AUTHOR]

The zirconium QDs have been synthesized using the chemical reduction method by using sodium borohydride as a reducing agent. The purity of the synthesized QDs was determined using EDS and EDX techniques. The XRD data indicate that the Zr QDs exist in both cubic and hexagonal lattice forms. The morphology of the Zr QDs is characterized by HRTEM and FESEM as homogeneous, small, spherical QDs of 5 nm to 6 nm diameter. The QDs exhibit chemiluminescence. The H2O2 sensitivities of Zr QDs have been studied. The changes in the intensity of emission spectra of Zr QDs at different wavelengths (406 nm, 430 nm, and 413 nm) satisfy the Stern–Volmer equation, thus proving to be promising candidates for their applications in biological science and as energy materials. [ABSTRACT FROM AUTHOR]

The OVs-rich BiOBr-(0 0 1)/Bi 2 SiO 5 /Bi S-scheme hybrid photocatalyst with efficient electron/hole separation and highly active for CO 2 reduction was designed and synthesized by the facile solvothermal strategy for high-efficient photocatalytic CO 2 reduction activity and stability to CO under simulated sunlight irradiation. [Display omitted] Photocatalysis CO 2 reduction into high-value-added chemical feedstocks is desirable for simultaneously addressing the solar energy storage, CO 2 excess and energy shortage issues. In this work, a kind of original S-scheme BiOBr-(0 0 1)/Bi 2 SiO 5 /Bi (OSB) heterostructure photocatalyst with rich oxygen vacancies is in-situ synthesized, which significantly promotes the photocatalytic CO 2 reduction performance. Interestingly, the lower formation energy of oxygen vacancy exhibits the easy feasibility on the BiOBr-(0 0 1) surface via the assistant of ultrasound. There exists the highest photocatalytic CO 2 reduction activity to CO of 234.05 μmol g-1h−1 for OSB-20 sample (ultrasound time: 20 min), higher 3.3 times than OSB-0 sample (without ultrasound). Combined with experimental and calculated results, the significative formation mechanism, widened light-response range, highly-efficient separation/transfer paths and improved redox-reduction abilities of photogenerated electron-hole pairs for S-scheme OSB-20 heterostructure are investigated and proposed. Our findings provide new insights for the construction and synthesis of the S-scheme Bi-based heterojunction photocatalyst system. [ABSTRACT FROM AUTHOR]

The size of silver nanoparticles plays a crucial role in their ultimate application in the medical and industrial fields, as their efficacy is enhanced by decreasing dimensions. This study presents two chemical synthesis procedures for obtaining silver particles and compares the results to a commercially available Ag-based product. The first procedure involves laboratory-based chemical reduction using D-glucose (C6H12O6) and NaOH as reducing agents, while the second approach utilizes trisodium citrate dehydrate (C6H5Na3O7·2H2O, TSC). The Ag nanoparticle suspensions were examined using FT-IR and UV-VIS spectroscopy, which indicated the formation of Ag particles. The dimensional properties were investigated using Atomic Force Microscopy (AFM) and confirmed by Dynamic Light Scattering (DLS). The results showed particle size from microparticles to nanoparticles, with a particle size of approximately 60 nm observed for the laboratory-based TSC synthesis approach. [ABSTRACT FROM AUTHOR]

Graphene-based materials may pose a potential risk for human health due to occupational exposure, mainly by inhalation. This study was carried out on bronchial epithelial 16HBE14o− cells to evaluate the role of chemical reduction and formulation of graphene oxide (GO) on its cytotoxic potential. To this end, the effects of GO were compared to its chemically reduced form (rGO) and its stable water dispersion (wdGO), by means of cell viability reduction, reactive oxygen species (ROS) generation, pro-inflammatory mediators release and genotoxicity. These materials induced a concentration-dependent cell viability reduction with the following potency rank: rGO > GO >> wdGO. After 24 h exposure, rGO reduced cell viability with an EC50 of 4.8 μg/mL (eight-fold lower than that of GO) and was the most potent material in inducing ROS generation, in contrast to wdGO. Cytokines release and genotoxicity (DNA damage and micronucleus induction) appeared low for all the materials, with wdGO showing the lowest effect, especially for the former. These results suggest a key role for GO reduction in increasing GO cytotoxic potential, probably due to material structure alterations resulting from the reduction process. In contrast, GO formulated in a stable dispersion seems to be the lowest cytotoxic material, presumably due to its lower cellular internalization and damaging capacity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrogen spillover induced a cooperative catalysis between Pd particles and Pd single atoms supported on carbon supports. • Few-layer graphene (FLG) support allows more extended H-spillover than multi-walled carbon nanotubes (CNT) • Pd/FLG is more active for solvent-free total hydrogenation of squalene than Pd/CNT but deactivated. • A new mechanism of thermal catalyst deactivation induced by H-spillover is proposed. General interest in solvent-free catalytic processes is driven by the development of environmentally and economically acceptable procedures. Such processes require the use of highly active and stable catalysts. This study reports on the synthesis, characterization, and kinetic evaluation of two highly active Pd catalysts supported on different carbons support, i.e., multi-walled carbon nanotubes (CNT) and few-layer graphene (FLG). These catalysts, with similar Pd loading (∼2 wt%) and containing both Pd single atoms (Pd SA) and nanoparticles (Pd NP), were systematically tested for solvent-free total hydrogenation of squalene (SQE) to obtain high-purity squalane (SQA). Thanks to the unique cooperative catalysis between Pd SA and Pd NP involving H-spillover, the activities of both catalysts were high compared to catalysts described in the literature. Solvent-free total hydrogenation of SQE could be performed under mild conditions (120 °C, 20 bar H 2 , 4 h) using ultralow Pd loading (60 ppm). However, since this reduction reaction is highly exothermic (ΔH R = − 765 kJ.mol−1), heat management during the reactor operation with these highly active catalysts is crucial to avoid deactivation and thermal runaway. Under these conditions, Pd/FLG was highly active but deactivated, unlike Pd/CNT, which still has high activity, but does not deactivate. Characterizations (ICP, XPS, Raman, TPD-MS, HAADF-STEM) of the Pd/FLG catalyst before and after reaction, supported by calculations based on density functional theory, allowed us to propose a new mechanism of catalyst deactivation involving the chemical reduction of specific surface oxygen groups of the carbon support induced by H-spillover. [ABSTRACT FROM AUTHOR]

Introduction: Non‐small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutation has a higher incidence of brain metastases than wild‐type EGFR mutations. Osimertinib, a third‐generation EGFR tyrosine kinase inhibitor (TKI), targets both EGFR‐TKI sensitizing and T790M‐resistance mutations and has a higher brain penetration rate relative to first‐ and second‐generation EGFR‐TKIs. Therefore, osimertinib has become a preferred first‐line therapy for advanced EGFR mutation‐positive NSCLC. However, lazertinib, an emerging EGFR‐TKI, has shown higher selectivity toward EGFR mutations and improved penetration of the blood–brain barrier compared to osimertinib in preclinical studies. This trial will evaluate the efficacy of lazertinib as a first‐line therapy in patients with EGFR mutation‐positive NSCLC who have brain metastases, with or without additional local therapy. Methods: This is a single‐center, open‐label, single‐arm phase II trial. A total of 75 patients with advanced EGFR mutation‐positive NSCLC will be recruited. Eligible patients will receive oral lazertinib 240 mg, once daily until disease progression or intolerable toxicity is detected. Patients with moderate to severe symptoms related to brain metastasis will simultaneously receive local therapy for the brain. The primary endpoints are progression‐free survival and intracranial progression‐free survival. Discussion: Lazertinib, in combination with local therapy for the brain, if necessary, is expected to improve the clinical benefit in advanced EGFR mutation‐positive NSCLC with brain metastases, as a first‐line treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] Solar-energy-driven CO 2 reduction for chemical reagents production, such as CH 3 OH, CH 4 and CO, has tremendous potential for carbon neutrality in the energy industries. However, the low reduction efficiency limits its applicability. Herein, W 18 O 49 /MnWO 4 (WMn) heterojunctions were prepared via one-step in-situ solvothermal process. Through this method, W 18 O 49 tightly combined with the surface of MnWO 4 nanofibers to form nanoflower heterojunction. It was found that under full spectrum light irradiation for 4 h, the yields of photoreduction of CO 2 to CO, CH 4 and CH 3 OH by 3–1 WMn heterojunction were 61.74, 71.30 and 18.98 μmol/g, respectively, which were 2.4, 1.8 and 1.1 times that of pristine W 18 O 49 , and ca.20 times that of pristine MnWO 4 towards CO production. Furthermore, even in the air atmosphere, the WMn heterojunction still performed excellent photocatalytic performance. Systematic investigations demonstrated that the catalytic performance of WMn heterojunction was improved by superior light utilization and more efficient photo-generated carrier separation and migration as compared with W 18 O 49 and MnWO 4. Meanwhile, the intermediate products of the photocatalytic CO 2 reduction process were also studied in detail by in-situ FTIR. Therefore, this study provides a new way for designing high efficiency of heterojunction for CO 2 reduction. [ABSTRACT FROM AUTHOR]

The Yellow River Delta is an important grain production base in China, and it is a typical Yellow River irrigated area. Chemical fertilizer overuse has seriously affected grain production safety, and understanding the fertilizer application situation is useful for scientific agronomy management. In this study, we collected the data of the N, P, K fertilizers for crop cultivation in Donging City from 2011 to 2020, and we collected 185 investigating questionnaires to gather information on the fertilizer application rate for small farmers. The results showed that the amount of total fertilizer used has decreased from the year 2015, but the macro element fertilizer rate for crop cultivation exceeded the recommended dosage. The application of compound fertilizer increased during the investigated 10 years, and its proportion in 2020 was 1.65 times higher than in 2011. For obtaining an ideal grain yield, the N and P2O5 had relative reduction rates of 67.8% and 69.6% for wheat planting. Furthermore, the relative reduction rates of N, P2O5, and K2O were 25.9%, 69.6%, and 59.7%, respectively, for maize cultivation when compared to the recommended dosage. During wheat growth, the potassium fertilizer was needed to increase the dosage, although the K element content in the soil was high. Furthermore, the medium and trace elements are all important nutrients for improving crop yield and quality which need to be studied. More scientific measurements should be conducted to match chemical fertilizer reduction to constructing healthy and sustainable agriculture in the Yellow River irrigated area. [ABSTRACT FROM AUTHOR]

In this study, 2D Co-B nanosheet-decorated 1D TiO2 nanofibers (2D Co-B NS-decorated 1D TiO2 NFs) are synthesized via electrospinning and an in situ chemical reduction technique. The as-prepared catalyst showed excellent catalytic performance in H2 generation from sodium borohydride (SBH). When compared to naked Co-B nanoparticles, the catalytic activity of the 2D Co-B NS-decorated 1D TiO2 NFs catalyst for the hydrolysis of SBH is significantly enhanced, as demonstrated by the high hydrogen generation rate (HGR) of 6020 mL min−1 g−1 at 25 °C. The activation energy of hydrolysis was measured to be 30.87 kJ mol−1, which agreed with the reported values. The catalyst also showed good stability. Moreover, the effects of SBH, catalyst concentration, and temperature on the catalytic performance of 2D Co-B NS-decorated 1D TiO2 NFs were studied to gain a comprehensive understanding of the dehydrogenation mechanism of SBH. Based on these findings, we conclude that 2D Co-B NS-decorated 1D TiO2 NFs are effective catalytic materials for the dehydrogenation of SBH. [ABSTRACT FROM AUTHOR]

This document is an editorial summary of a special issue of the journal "Materials" focused on the recovery of non-ferrous metals from metallurgical residues. The issue includes papers on various topics such as the recovery of metals from historic slag, the application of microwave technology in metal recovery, and the preparation of advanced materials using chemical reduction methods. It also covers attempts to optimize traditional metallurgical processes, such as limonite pellet technology for iron making and the use of electromagnetic stirring in steel production. The summary provides a brief overview of the articles included in the special issue, highlighting their key findings and contributions to the field. [Extracted from the article]

Dopamine was used to modify polytetrafluoroethylene (PTFE) in order to obtain functional polydopamine (PDA) surface-modified PTFE microporous film (PTFE@PDA). Ag was deposited on the surface of PTFE@PDA using electroless plating in order to obtain Ag-wrapped PTFE@PDA film (PTFE@Ag). A liquid-phase chemical reduction method was employed to prepare nickel nanochains. A Ni@PVDF cast film was obtained by mechanically blended nickel nanochains and polyimide (PVDF). The above two films were hot pressed to give a flexible, ultra-thin, and highly effective electromagnetic shielding composite film with a "3+2" layered structure. IR, XRD, and TEM results showed the PTFE@PDA film surface was coated by a tight plating layer of Ag particles with a particle size of 100~200 nm. PTFE@Ag+Ni@PVDF composite film exhibited excellent electromagnetic shielding effectiveness, with the conductivity of 7507.5 S/cm and the shielding effectiveness of 69.03 dB in the X-band range. After a 2000-cycle bending, this value still remained at 51.90 dB. Furthermore, the composite film presented excellent tensile strength of 62.1 MPa. It has great potential for applications in flexible and wearable intelligent devices. [ABSTRACT FROM AUTHOR]

The role of nanotechnology is increasingly important in our society. Through it, scientists are acquiring the ability to understand the structure and properties of materials and manipulate them at the scale of atoms and molecules. Nanomaterials are at the forefront of the rapidly growing field of nanotechnology. The synthesis of nanostructured materials, especially metallic nanoparticles, has attracted tremendous interest over the past decade due to their unique properties, making these materials excellent and indispensable in many areas of human activity. These special properties can be attributed to the small size and large specific surface area of nanoparticles, which are very different from those of bulk materials. Nanoparticles of different sizes and shapes are needed for many applications, so a variety of protocols are required to produce monodisperse nanoparticles with controlled morphology. The purpose of this review is firstly to introduce the reader to the basic aspects related to the field of nanotechnology and, secondly, to discuss metallic nanoparticles in greater detail. This article explains the basic concepts of nanotechnology, introduces methods for synthesizing nanoparticles, and describes their types, properties, and possible applications. Of many methods proposed for the synthesis of metal nanoparticles, a chemical reduction is usually preferred because it is easy to perform, cost-effective, efficient, and also allows control of the structural parameters through optimization of the synthesis conditions. Therefore, a chemical reduction method is discussed in more detail—each factor needed for the synthesis of nanoparticles by chemical reduction is described in detail, i.e., metal precursors, solvents, reducing agents, and stabilizers. The methods that are used to characterize nanomaterials are described. Finally, based on the available literature collection, it is shown how changing the synthesis parameters/methods affects the final characteristics of nanoparticles. [ABSTRACT FROM AUTHOR]

The NaGdF4:Nd3+@Ni core@shell nanoparticles were synthesized and characterized. First, core@shell nanoparticles were synthesized using a solvothermal method to obtain the NaGdF4:Nd3+ core with hexagonal phase; subsequently, a chemical reduction was performed to stimulate the growth of the Ni shell with cubic phase. NaGdF4:Nd3+@Ni nanoparticles were characterized by transmission electron microscope, zeta potential, X-ray diffraction, scattered energy spectroscopy, UV-Vis, and photoluminescence emission spectra. The nanoparticles were round in shape, with mean sizes around 250 nm. The core@shell nanoparticles presented a homogenous composition and good stability. The photoluminescent emission of the nanoparticles was recorded at 1059 nm in the near-infrared spectral range; this band corresponds to the 4F3/2→4I11/2 radiative transitions of Nd3+ ions. The synthesized nanoparticles, being hydrophilic, have potential for use in different areas, one of them could be in anaerobic digestion. [ABSTRACT FROM AUTHOR]