Simple Solution Plasma Synthesis of Ni@NiO as High-Performance Anode Material For Lithium-ion Batteries Application.

The pursuit of straightforward and cost-effective methods for synthesizing high-performance anode materials for lithium-ion batteries is a topic of significant interest. This study elucidates a one-step synthesis approach for a conversion composite using glow discharge in a nickel formate solution, yielding a composite precursor comprising metallic nickel, nickel hydroxide, and basic nickel salts. Subsequent annealing of the precursor facilitated the formation of the Ni@NiO composite, exhibiting exceptional electrochemical properties as anode material in Li-ion batteries: a capacity of approximately 1000 mAh·g-1, cyclic stability exceeding 100 cycles, and favorable rate performance (200 mAh·g-1 at 10 A·g-1). Comparative analysis across various methods for synthesizing NiO-based materials underscored the superiority of the Ni@NiO composite. Furthermore, an assessment of resource costs demonstrated the cost-effectiveness and scalability of the approach in terms of resource consumption per Ah. Lastly, the integration of a Ni@NiO anode with an NMC532 cathode in a full battery highlights Ni@NiO's potential for conversion anodes, achieving a practical gravimetric energy density of 92 Wh kg-1.

High-strength gypsum binder with improved water-resistance coefficient derived from industrial wastes.

The article presents the possibility of increasing the water resistance of gypsum binders (GBs) obtained based on synthetic gypsum by introducing additives derived from industrial wastes. Regularities were obtained for the influence of the type and amount of additives on the water/gypsum ratio (W/G), strength indicators and water resistance of high-strength GB. The introduction of a single-component additive to improve water resistance does not have a significant effect. Complex additives based on Portland cement, granulated blast-furnace slag, electric steel-smelting slag, expanded clay dust and granite screenings of various fractions have been developed that make the maximum contribution to improving the water resistance of a high-strength GB based on synthetic calcium sulphate dihydrate, which made it possible to increase the water-resistance coefficient from 0.39 to 0.82.

Recovery of carbon from spent carbon cathode by alkaline and acid leaching and thermal treatment and exploration of its application in lithium-ion batteries.

The spent carbon cathode (SCC) is a hazardous solid waste from aluminum production. It has an abundant carbon source and a unique graphitic carbon layer structure, making it a valuable waste for recycling. This paper uses alkaline and acid leaching methods to report a straightforward way of extracting recovered carbon (RC) from SCC as anode material for lithium-ion batteries (LIBs). The results show that alkaline and acid leaching conditions at 70 °C with 1 M NaOH and HCl solution individually in 6 h and a liquid-solid ratio of 20:1 can result in RC with up to 94.63% carbon content than 49.38% in SCC, exhibiting a typical graphite structure. SCC and RC materials are obtained after calcination at 400 °C in an inert atmosphere and used as anode materials (SCC-400 and RC-400). In this paper, The initial charging specific capacities are 490.0 mA h g-1, 195.4 mA h g-1, and 423.2 mA h g-1and initial coulombic efficiencies (ICE) are 67.8%, 78.9%, and 72.0% of RC-400, SCC, and SCC-400. RC-400 also shows excellent capacity retention and impedance values. This exciting finding provides a viable, non-hazardous, and resourceful method for treating and disposing of SCC from aluminum electrolysis.

Combustion Synthesis of Magnesium-Aluminum Oxynitride MgAlON with Tunable Composition.

Magnesium-aluminum oxynitride MgAlON has garnered significant attention in recent years due to its unique properties and potential applications. Herein, we report a systematic study on the synthesis of MgAlON with tunable composition by employing the combustion method. The Al/Al2O3/MgO mixture was combusted in nitrogen gas, and the effects of Al nitriding and oxidation by Mg(ClO4)2 on the exothermicity of the mixture, combustion kinetics, and phase composition of combustion products were investigated. Our results demonstrate that the MgAlON lattice parameter can be controlled by varying the AlON/MgAl2O4 ratio in the mixture, which corresponds to the MgO content in the combustion products. This work provides a new pathway for tailoring the properties of MgAlON, which may have significant implications in various technological applications. In particular, we reveal the dependence of the MgAlON lattice parameter on the AlON/MgAl2O4 ratio. The limitation of the combustion temperature by 1650 °C resulted in obtaining submicron powders with a specific surface area of about 3.8 m/g2.

Development of a new design of deironing granulated filter for joint removal of iron and ammonium nitrogen from underground water.

Providing the population with high-quality drinking water is one of the main state tasks. Rural water supply systems and water supply systems of small settlements in the region require special attention, namely, the development of technologies for individual, small-sized water treatment equipment, as well as equipment for collective use, designed to purify groundwater for drinking purposes. In many areas, there are groundwaters containing excess levels of several pollutants, which makes their purification much more difficult. Elimination of shortcomings in the known methods of water iron removal is possible by reconstructing existing water supply systems from underground sources in small settlements. A rational solution is to search for groundwater treatment technologies that make it possible to provide the population with high-quality drinking water at a lower cost. The result of increasing the concentration of oxygen in water was obtained in the process of modifying the filter by changing the excess air exhaust system, which was made in the form of a perforated pipeline located in the lower half of the granular filter layer connected to the upper branch pipe. At the same time, high-quality groundwater treatment, sufficient simplicity and reliability in operation are ensured, local conditions and the inaccessibility of many objects and settlements in the region are taken into account as much as possible. After the filter was upgraded, the concentration of iron decreased from 4.4 to 0.27 mg/L and ammonium nitrogen from 3.5 to 1.5 mg/L.

Synthesis and effect of CoCuFeNi high entropy alloy nanoparticles on seed germination, plant growth, and microorganisms inactivation activity.

Implementation of nanotechnology in agriculture is of interest primarily to improve the growth and productivity of crops, and to minimize the use of traditional expensive chemical fertilizers. This work presents a simple energy-conservative approach for the synthesis of CoCuFeNi high entropy alloy nanoparticles (HEA-NPs) capable of forming a stable suspension with a concentration of 0.3 g/L. The size, composition, and morphology of the nanoparticles were analyzed by XRD, SEM, TEM, and EDS. Obtained HEA-NPs were characterized by fine crystallinity with an average size of 25 nm. The investigated suspensions of HEA-NPs were tested for seeds germination and plants growth. The use of suspension of CoCuFeNi HEA-NPs for plant irrigating together with ordinary water showed positive results in plant biostimulation, which resulted in the plant height up to 12% for watercress and up to 50% for oil radish. CoCuFeNi HEA-NPs showed nice inactivation activity for Pseudomonas aeruginosa that was comparable for the use of Tetracycline.

Approaches for filtrate utilization from synthetic gypsum production.

Waste recycling and industrial wastewater treatment have always been of interest. A green approach was developed for the filtrate of synthetic gypsum production from water treatment coagulation sediments and spent sulfuric acid. Due to the high concentration of iron sulfate, concentrated filtrate showed good coagulation results, which were 5% lower than pure iron sulfate. In addition, a high concentration of iron facilitates its use as a precursor for synthesizing magnetic sorbents and photocatalysts. Such materials were synthesized by the solution combustion synthesis method. Oil sorption capacity reached 1.8 g/g, comparable to some synthetic materials and higher than sorption materials based on natural materials. Photodegradation of acid telon blue dye after 90 min of irradiation time was 82.7% with catalyst derived from filtrate compared to the just dye solution with 17.6% efficiency. The reaction rate constant for the photocatalyst sample was up to 11.4-fold higher compared with only UV treatment. The neutralized filtrate containing sulfur, calcium, magnesium, and sodium has been tested as a complex fertilizer. The results of bioindication for oil radish showed up to a 15% increase in the shoot length. A number of techno-economic indicators show that such an approach is advantageous from a technological, environmental, and economic point of view.

Low-temperature method for desiliconization of polymetallic slags by ammonium bifluoride solution.

Throughout the period of operation of non-ferrous metal deposits, a significant amount of waste has been accumulated. The accumulated waste contains valuable metals in concentrations that allow considering them as valuable raw materials. However, it is worth noticing the presence of problems that previously did not allow for more complete extraction of the target components. Such problems include the presence of significant amounts of silicon dioxide in the form of a silicate matrix, the removal of which will allow the extraction of valuable components with the elimination of industrial waste areas. The paper considers a method for removing silicon from the polymetallic slags. According to the results of the work, it was found that silicon passes into solution in the form of ammonium hexafluorosilicate. Iron, aluminum, and a number of other components react with ammonium hydrofluoride, but do not leach into the solution due to their low solubility in the resulting system. After removing silicon, the solid residue was subjected to pyrohydrolysis to obtain a product that can be subjected to magnetic separation to obtain a magnetic iron concentrate and a non-ferrous metal concentrate. The formed concentrate can later be used to extract zinc, lead, silver, etc. The productive solution was directed to the deposition of silicon with the subsequent production of silicon dioxide. The resulting solution can be directed to evaporation in order to regenerate and reuse ammonium hydrodifluoride.

Reuse of walnut shell waste in the development of fired ceramic bricks.

The development of agricultural waste-doped fired bricks is an important step toward achieving lightweight eco-efficient bricks with improved thermal insulation property. Recent research in masonry has been tailored towards the production of energy-efficient building by incorporating waste materials as additives. This effectuates a safe waste disposal, cost effectiveness, and also serve as a giant stride towards environmental sustainability. This study examines the viability of using walnut shell as additive in fired clay at various firing temperatures. Pulverized walnut shell was added to clay at a proportion of 0-10 wt.% by weight of clay. The samples were fired at temperatures of 950 °C and 1100 °C. The samples were probed for mechanical properties and durability. Morphology of the brick samples were examined under scanning electron microscope. The result of the research showed increased water absorption and specific heat capacity while mechanical and bulk density were observed to reduce. Linear shrinkage and thermal conductivity reduced with increase in walnut content of which linear shrinkage and thermal conductivity values experienced at 1100 °C was higher than at 950 °C. Resistance of bricks to salt crystallization increased with firing temperature. All samples met various standard requirement for masonry except sample prepared with 10 wt.% walnut shell whose compressive and flexural strengths fell below the required standard. The study established the use of walnut shell for development of sustainable energy-efficient bricks.

Paperbricks produced from wastes: modeling and optimization of compressive strength by response surface approach.

The high cost of building materials occasioned by the increased cost of constituent materials has contributed immensely to the problem of housing deficit faced in Africa and major developing countries of the world. Waste paper can be recycled into bricks but there are limited studies to that effect. Waste glass is used as partial cement replacement to reduce the cost of cement and is also used as a pozzolan. This study focused on the development of paperbricks from the wastes of paper and glass. Response surface method (RSM) was involved in the design of the experiment involving 4 factors: glass powder replacement of cement (A), curing duration (B), compaction pressure (C), and water/cement ratio (D). Box-Behnken method was engaged for the 4-factor, 3-level design. The result of ANOVA showed that experimental inputs had a significant effect on compressive strength response. Factors A, B, and C had a synergetic effect on the response while factor D had an antagonistic effect on the response. Combined interaction between the factors that the response depended on the interactive patterns of the factors. A statistical fit model was developed to predict the compressive strength of the composite. RSM optimization revealed a combination of 36.68%, 57.82 days, 8.50 MPa, and 0.364 for factors A, B, C, and D, respectively, predicting a strength value of 7.358 MPa. Validation experiment carried out using the optimal conditions yielded 7.54 MPa; a deviation of + 0.0247. Since the deviation is less than ± 0.05, the model was statistically validated and fit.

Mathematical modelling, multi-objective optimization, and compliance reliability of paper-derived eco-composites.

The quest for cost-effective and thermal efficient structural materials onto beating the high cost of construction is gaining more attention among researchers. This study focused on the blending of cement and sand with waste paper pulp into cost-effective structural materials. The composites were prepared in four mix groups with each containing a fixed amount of sand at 5, 10, 15, and 20 wt.% (by weight of pulp). Cement was varied at 10, 20, 30, and 40 wt.% in each group, and curing was done for 28 days. Properties evaluated are compressive, bending, and splitting strengths. It was observed that increasing cement and sand contents enhanced strengths; howbeit, the blend of 30 wt.% cement/15 wt.% sand resulted in a reduction in bending strength even as 30 wt.% cement/20 wt.% sand engendered a decrease in bending and splitting strength. The microstructural features showed that inherent fibers of the pulp were well bonded with hydration products and sand content yielding good performance in the composites. The optimization procedure carried out depicted a combination of 35.27% cement and 20% sand as the optimum composition. Experimental outcomes were modelled for the purpose of prediction of responses. The models were confirmed statistically fit showing how varying cement content affected strength responses at fixed sand proportion. ANOVA affirmed the significant contribution of cement and sand on the strength responses. Compliance reliability was observed to be dependent on the interactive pattern between cement and sand. Going by the standard prescription for the strength properties, cement and sand content of 35.27 and sand 20 wt.% satisfied all strength requirements for low-cost construction having a compliance reliability of 1.31.

Modeling, multi-response optimization, and performance reliability of green metal composites produced from municipal wastes.

For the purpose of reducing and reusing municipal wastes, used aluminum products, waste glass, and rice husk were selected and reprocessed into green-metal composite. The process entailed recycling of waste glass and rice husk into glass powder (GP) and rice husk ash (RHA), respectively. These were employed as additives in recycled aluminum melt. Composite samples development entailed group mixes A, B, C, and D. Group mix A was prepared by the blend of 3 wt.% RHA at constant proportion with 2, 4, 6, 8, and 10 wt.% GP. Regarding group mixes B, C, D, the same proportion of GP was blended with 6, 9, 12% RHA at constant dosage respectively. Mechanical properties; tensile, impact, flexural and compressive strengths, and fracture toughness were investigated. The significance of the additives on the composites was appraised via performance reliability index (PRI) as a measure of effective property based on variable experimental inputs. From the results, the commix of 3% RHA and 4, 6, 8% GP; 6% RHA and 2, 4, 6% GP; 9% RHA and 2, 4% GP exhibited enhancement of effective property. The compressive strength of the composites was showcased to be the most improved mechanical property. Maximum improvement was obtained at the collage of 4% GP and 6% RHA, yielding a PRI of 1.35. Results of the ANOVA revealed that the experimental inputs had significant contribution on each property response. Mathematical models were developed for each property response, and multi-response optimization predicted an optimum mix of 3.93 wt.% GP and 6.14% RHA. The difference between the property value of the predicted and confirmation experiment is < ± 0.05, validating the models.

Mechanical performance and Taguchi optimization of kenaf fiber/cement-paperboard composite for interior application.

Demand for particleboards keeps increasing and as such more trees are fell for its production, engendering deforestation. For the purpose of reducing falling of trees, this study, focused on recycling of waste paper in the development of paperboard as alternative to particleboards used for furniture and interior household applications. Kenaf fiber (KF) was blended at varying proportions of 0, 1, 2, 3, 4, and 5 wt.% with 20 wt.% constant cement and 20 wt.% constant coconut shell powder while the remaining was paper pulp. Board specimen developed were cured for 14, 28, and 90 days and mechanical properties were examined. Results obtained showed that fiber dosage improved bond strength and screw holding strengths as compared with the control mix. Similarly, modulus of rupture was enhanced with KF loading as compared with control mix while 1 to 3 wt.% KF spawned enhancement of modulus of elasticity. However, 4 and 5 wt.% KF led to a reduction in the modulus. Infusion of the fiber enhanced tensile strength from 1 to 3 wt.% content. 14-day and 28-day curing periods were observed to improve properties while the 90-day curing period is detrimental to all properties. Optimization via signal-to-noise ratio revealed an optimum mix of 2 wt.% obtained for fiber and an optimum curing duration of 28 days.

Recycling of synthetic waste wig fiber in the production of cement-adobe for building envelope: physio-hydric properties.

Waste wigs are often disposed off in their volume on landfills, thus constituting a nuisance to the environment. Recycling these wigs in masonry bricks is a way via which they can be recycled and reused. On such premise, waste wig fiber (WWF) was recycled by incorporating into the cement-sand-clay composite mix for masonry bricks production. The challenges masonry bricks face include shrinkage and water susceptibility; hence, the contributory effect of WWF on physio-hydric properties was assessed in this study. Sample preparation entailed blending of cement, sand, clay soil, and waste wig fiber. The control mix was prepared by commixing clay with 10% cement (by clay volume) and 20% sand (by clay volume). Other mix proportions were reinforced with 1, 2, 3, 4, and 5% WWF by clay volume. Prepared composite brick samples were cured for 28 and 56 days and tested for physio-hydric properties. Results revealed WWF contributed significantly in improving hydro-resisting properties by minimizing porosity, water and moisture absorption, capillary suction, and water permeability. Furthermore, WWF contributed to dimensional stability by reducing shrinkages and weight loss. Hydration time impacts significantly in reducing apparent porosity, water permeability coefficient, moisture and water absorption, and capillary suction coefficient and increasing apparent density, weight loss, linear, and volumetric shrinkage. The general outcome depicts that WWF showed promising performance in bricks developed in enhancing water and moisture susceptibility resistance and promoting mass and dimensional stability, hence can be employed in reinforcing cement adobe bricks at an optimum mix of 5% vol fraction.

Ecological problems of environment mudflows and their prediction: experience of Georgia.

Among the natural disasters on the planet, especially in the mountainous and foothill regions, it is widespread erosive-debris flow events, which have the most significant environmental and economic damage to humanity. Georgia is no exception. This paper aims to develop a new methodology to calculate the predictive quantities of debris flow, essential for implementing anti-debris flow measures. Based on the available data and various calculations, a completely new empirical approach has been adopted to calculate predictive quantities of debris flow spent, predicting debris flow spent in the mountains and foothill regions of Georgia. The suggested methodology reflects the physics of debris-flow processes at a very high level and can be applied to calculate debris flow in various world regions.

Genotoxicity and inflammatory potential of stainless steel welding fume particles: an in vitro study on standard vs Cr(VI)-reduced flux-cored wires and the role of released metals.

Welders are daily exposed to various levels of welding fumes containing several metals. This exposure can lead to an increased risk for different health effects which serves as a driving force to develop new methods that generate less toxic fumes. The aim of this study was to explore the role of released metals for welding particle-induced toxicity and to test the hypothesis that a reduction of Cr(VI) in welding fumes results in less toxicity by comparing the welding fume particles of optimized Cr(VI)-reduced flux-cored wires (FCWs) to standard FCWs. The welding particles were thoroughly characterized, and toxicity (cell viability, DNA damage and inflammation) was assessed following exposure to welding particles as well as their released metal fraction using cultured human bronchial epithelial cells (HBEC-3kt, 5-100 µg/mL) and human monocyte-derived macrophages (THP-1, 10-50 µg/mL). The results showed that all Cr was released as Cr(VI) for welding particles generated using standard FCWs whereas only minor levels (< 3% of total Cr) were released from the newly developed FCWs. Furthermore, the new FCWs were considerably less cytotoxic and did not cause any DNA damage in the doses tested. For the standard FCWs, the Cr(VI) released in cell media seemed to explain a large part of the cytotoxicity and DNA damage. In contrast, all particles caused rather similar inflammatory effects suggesting different underlying mechanisms. Taken together, this study suggests a potential benefit of substituting standard FCWs with Cr(VI)-reduced wires to achieve less toxic welding fumes and thus reduced risks for welders.

Detection of gold cysteine thiolate complexes on gold nanoparticles with time-of-flight secondary ion mass spectrometry.

Gold (Au) nanoparticles (NPs) are widely used in nanomedical applications as a carrier for molecules designed for different functionalities. Previous findings suggested that biological molecules, including amino acids, could contribute to the dissolution of Au NPs in physiological environments and that this phenomenon was size-dependent. We, therefore, investigated the interactions of L-cysteine with 5-nm Au NPs by means of time-of-flight secondary ion mass spectrometry (ToF-SIMS). This was achieved by loading Au NPs on a clean aluminum (Al) foil and immersing it in an aqueous solution containing L-cysteine. Upon rinsing off the excessive cysteine molecules, ToF-SIMS confirmed the formation of gold cysteine thiolate via the detection of not only the Au-S bond but also the hydrogenated gold cysteine thiolate molecular ion. The presence of NaCl or a 2-(N-morpholino)ethanesulfonic acid buffer disabled the detection of Au NPs on the Al foil. The detection of larger (50-nm) Au NPs was possible but resulted in weaker cysteine and gold signals, and no detected gold cysteine thiolate signals. Nano-gold specific adsorption of L-cysteine was also demonstrated by cyclic voltammetry using paraffine-impregnated graphite electrodes with deposited Au NPs. We demonstrate that the superior chemical selectivity and surface sensitivity of ToF-SIMS, via detection of elemental and molecular species, provide a unique ability to identify the adsorption of cysteine and formation of gold-cysteine bonds on Au NPs.

Corrosion and transformation of solution combustion synthesized Co, Ni and CoNi nanoparticles in synthetic freshwater with and without natural organic matter.

Pure metallic Co, Ni, and their bimetallic compositions of Co3Ni, CoNi, and CoNi3 nanomaterials were prepared by solution combustion synthesis. Microstructure, phase composition, and crystalline structure of these nanoparticles (NPs) were characterized along with studies of their corrosion and dissolution properties in synthetic freshwater with and without natural organic matter (NOM). The nanomaterials consisted of aggregates of fine NPs (3-30 nm) of almost pure metallic and bimetallic crystal phases with a thin surface oxide covered by a thin carbon shell. The nanomaterials were characterized by BET surface areas ranging from ~ 1 to 8 m2/g for the Ni and Co NPs, to 22.93 m2/g, 14.86 m2/g, and 10.53 m2/g for the Co3Ni, CoNi, CoNi3 NPs, respectively. More Co and Ni were released from the bimetallic NPs compared with the pure metals although their corrosion current densities were lower. In contrast to findings for the pure metal NPs, the presence of NOM increased the release of Co and Ni from the bimetallic NPs in freshwater compared to freshwater only even though its presence reduced the corrosion rate (current density). It was shown that the properties of the bimetallic nanomaterials were influenced by multiple factors such as their composition, including carbon shell, type of surface oxides, and the entropy of mixing.

Pigments from spent Zn, Ni, Cu, and Cd electrolytes from electroplating industry.

One of the problems of electroplating industry is the periodic discharge of concentrated spent electrolytes together with rinsing wastewater. This leads to irreversible loss of valuable components, as well as to the risk of heavy metal ions entering the environment, which have toxic, mutagenic, and carcinogenic effects. The paper presents research on the processing of spent electrolytes from electroplating industry of zinc, nickel, copper, and cadmium plating, collected over 3 years. Pigments of various colors were obtained by precipitation of zinc, nickel, copper, and cadmium ions by phosphate, hydroxide, and sodium carbonate. By their properties, i.e., whiteness 95-97%, residue after sieving on a sieve up to 0.04 wt.%, etc., the resulting pigments are not inferior to those currently presented on the world market. Following previous studies, a basic technological scheme for processing waste electrolytes with pigments production is proposed. Processing of spent electrolytes according to the proposed technology will make it possible to reduce the concentration of heavy metal ions to acceptable values (0.13-0.65 mg/L) for discharge. This will ensure stable and uninterrupted operation of local treatment facilities of electroplating industry.

CO oxidation and organic dyes degradation over graphene-Cu and graphene-CuNi catalysts obtained by solution combustion synthesis.

Graphene and its analogs in combination with metal nanopowders are among the most promising catalysts for various industry valuable processes. The newly obtained solution combustion synthesized graphene-Cu and graphene-CuNi nanocomposites were examined in heterogeneous catalysis of thermal activated CO oxidation and photoactivated degradation of acid telon blue and direct blue dyes. The nanocomposites are characterized by a closely connected solution combustion synthesized graphene-metal structure with a number of graphene layers from 1 to 3 and fine metal grains sizes of 31 nm (Cu) and 14 nm (CuNi). The experimental data showed the obtained graphene-metal nanocomposites are among the most effective catalysts for CO oxidation with a temperature of 100% conversion of 150 °C and 200 °C for Cu and CuNi containing catalysts, respectively. At the same time, both nanopowders were found inactive for dyes degradation.