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This study investigated cellobionate production from a lignocellulosic substrate using Neurospora crassa HL10. Utilizing NaOH-pretreated wheat straw as the substrate obviated the need for an exogenous redox mediator addition, as lignin contained in the pretreated wheat served as a natural mediator. The low laccase production by N. crassa HL10 on pretreated wheat straw caused slow cellobionate production, and exogenous laccase addition accelerated the process. Cycloheximide induced substantial laccase production in N. crassa HL10, enabling the strain to yield approximately 57 mM cellobionate from pretreated wheat straw (equivalent to 20 g/L cellulose), shortening the conversion time from 8 to 6 days. About 92% of the cellulose contained in the pretreated wheat straw is converted to cellobionate. In contrast to existing methods requiring pure cellobiose or cellulase enzymes, this process efficiently converts a low-cost feedstock into cellobionate at a high yield without enzyme or redox mediator supplementation.

This article systematically investigated the improvement effect of polypropylene fiber (PPF) on the mechanical and freeze–thaw properties of alkali-activated fly ash slag concrete (AAFSC) with high fly ash content and cured at room temperature. Fly ash and slag were used as precursors, with fly ash accounting for 80% of the total mass. A mixed solution of sodium hydroxide and sodium silicate was used as alkali activator, and short-cut PPF was added to improve the performance of AAFSC. Firstly, the strength characteristics of AAFSC at different curing ages were studied. Then, key indicators such as morphology, residual compressive strength, weight loss, relative dynamic modulus of elasticity (RDME), and pore characteristics of AAFSC after different freeze–thaw cycles were tested and analyzed. The strength performance analysis showed that the optimal dosage of PPF was 0.90%. When the alkali equivalent of the alkali activator was increased from 4% to 6%, the frost resistance of AAFSC could be improved. Furthermore, adding 0.90% PPF could increase the freeze–thaw cycle number of AAFSC by about 50 times (measured by RDME). With the increase in freeze–thaw cycles, the porosity of AAFSC increased, the fractal dimension decreased, and the proportion of harmless and less harmful pores decreased, while the proportion of harmful and multiple harmful pores increased. The relationship model between the porosity and compressive strength of AAFSC after freeze–thaw cycles was established. [ABSTRACT FROM AUTHOR]

The rising demand for materials that can be sustained over time and the growing worries about the decline of the environment have resulted in a noteworthy rise in the attention towards environmentally friendly composites in recent times. This study aims to develop a bio-composite by reinforcing ramie fiber (RF) within the ABS/CS blend matrix, to enhance the mechanical characteristics and biodegradability. The surface roughness of the fibers increased by chemical treatment using sodium hydroxide (NaOH). The ABS/CS/RF composites underwent compounding through a two-roll mill, and sheets containing different weight percentages (5, 10, 15, 20) of RF were produced using a hot compression molding machine. The prepared composites were tested to evaluate their biodegradability, water absorption, mechanical properties, and viscoelastic characteristics. The biodegradation test results demonstrated that there was a positive correlation between the concentration of fibers in neat ABS and the degree of biodegradation. The tensile strength and modulus of the ABS/CS blend increased by 60% and 14.28% respectively. The impact strength improved by 117% when 20 wt% of the RF was added. The degradation of the ABS/CS/RF composite increased by 1.375% after 45 days. However, the DMA results showed an adverse effect on the storage modulus. [ABSTRACT FROM AUTHOR]

High-strength carbon fibers were recovered by a new method, involving the decomposition of the thermosetting resin part of carbon fiber-reinforced plastic (CFRP) by heating it in a mixture of sodium hydroxide (NaOH) and potassium hydroxide (KOH). Alkali molten hydroxide was prepared by heating the mixture of NaOH and KOH at various ratios (NaOH: KOH = 1:0, 3:1, 1:1, 1:3, 0:1) at 400oC, and the CFRP was then heated with the aforementioned alkali molten hydroxide under a nitrogen atmosphere at 200–400oC for 0–90 min. Subsequently, the CFRP was washed with distilled water and filtered to recover the carbon fibers, and its tensile strength was estimated. Carbon fibers with higher strength can be recovered by heating the CFRP with an alkali molten hydroxide. As the temperature increased, the strength of the recovered carbon fiber decreased owing to the increase in gas generation caused by the decomposition of the thermosetting resin and carbon fiber in the molten hydroxide, such as H2 and CH4. KOH increase in the alkali molten hydroxide promoted decomposition of the resin, whereas the fiber was degraded. High-strength carbon fiber, nearly the same as virgin fiber, can be recovered at 200oC using the NaOH: KOH molten hydroxide at a ratio of 1:3. [ABSTRACT FROM AUTHOR]

This study comprises two distinct but interrelated parts. The first part involves optimizing the conditions for the conversion of phosphogypsum to a Ca(OH)2 and Na2SO4 solution. The second part focuses on enhancing the mechanical properties of gypsum through the use of a sodium sulphate additive derived from the conversion of phosphogypsum. An ultrasonic disperser was employed to accelerate the reaction between phosphogypsum and a sodium hydroxide solution. The mean dispersion time was found to be 0.2, 0.5, 1.0, and 2.0 min. The resulting product was a solution of calcium hydroxide and sodium sulfate. The impact of varying quantities of Na2SO4 on the compressive strength and density of building gypsum samples was investigated. An increase in the quantity of sodium sulphate from 0.2% to 2% resulted in a notable rise in the density of the building gypsum samples, from 1127 kg/m3 in the reference sample to 1264 kg/m3 in the sample containing 2% sodium sulphate. Therefore, in all instances, the utilization of the Na2SO4 additive in the gypsum samples resulted in elevated compressive strengths (4.8–8.6 MPa) in comparison to the reference sample devoid of this additive (1.6 MPa). [ABSTRACT FROM AUTHOR]

As carbon dioxide (CO2) emissions rapidly increase, alternative strategies are needed to capture and mitigate carbon dioxide using microorganisms. To enhance CO2 fixation and biomass production in microalgae, achieving the optimum concentration of dissolved carbon in the culture medium is essential. This study focuses on enhancing biomass production and CO2 biofixation efficiency in Chlorella sp. BRE5 by increasing dissolved inorganic carbon (DIC) through the strategic use of sodium hydroxide (NaOH) and CO2. Under shake flask study, the highest specific growth rate of 0.195 day−1, biomass productivity of 123.2 mg/L/day, and CO2 biofixation rate of 231.6 mg/L/day were found at NaOH dose of 0.25 g/L with CO2 (1%, v/v) supplementation. Further, optimized NaOH with different supply strategies of 1% CO2 was conducted in a photobioreactor (PBR) study. The best result was observed in PBR, where 1% CO2 strategically sparged (3-day intervals) with optimum NaOH dose. Under this condition, biomass yield, CO2 consumption rate, lipid productivity, and lipid content were found to be 2.25, 2.25, 4.19, and 1.87 times higher than the control. The outdoor cultivation of microalgae using a DIY bottle bioreactor (DIY BBR) was performed, resulting in less biomass and lipid productivity than that of the PBR study due to uncontrolled environmental conditions. The fatty acid methyl ester (FAME) profile comprised C16-C18 (84.86–90.69%), indicating the suitability for biodiesel production. This strategic supply of combined NaOH and CO2 enhances DIC in the medium, facilitating both the CO2 biofixation rate and biomass production. [ABSTRACT FROM AUTHOR]

The use of mixed microalgae offers an effective solution for the management of contamination risks in cultivation while enhancing economic viability. In this study, mixed microalgae were used for the first time for the removal of copper (Cu) and nickel (Ni) from aqueous solutions. The characteristics of the adsorbents were examined thoroughly, and the adsorption process was assessed using isotherms, kinetics, and thermodynamics. Particle size, concentration, contact time, temperature, and pH were among the variables assessed. The findings demonstrated that, at an initial concentration of 100 mg L–1 and a pH of 6, the maximum adsorption of Cu with a particle size of 1 mm (90.20%) took place in 60 min. The highest adsorption rate (78.25%) was found for Ni. Microalgae performed best over 180 min at room temperature and at pH values that promoted metal dissolution. The removal percentages of wet and dried microalgae were comparable, and the wet adsorbent was more economical. It was feasible to remove both metals at the same time. Up to three cycles of adsorbent reuse were possible, with sodium hydroxide treatment offering superior removal to hydrochloric acid. Thermodynamic analysis demonstrated that this process, which results in a disordered state, is exothermic and spontaneous. [ABSTRACT FROM AUTHOR]

The mineral carbonation process was proposed for effective CO2 capture and utilization from flue gas streams, such as those emitted by coal-fired power plants. In the present work, an alternative technology using sodium hydroxide (NaOH) solution as an absorbent for capturing CO2 and converting it into value-added materials while mitigating emissions was provided. This research examined the use of a packed bed reactor and a bubble column reactor for CO2 absorption and carbonation of NaOH solution to produce sodium bicarbonate (NaHCO3), offering a more environmentally friendly production process compared to traditional methods. The influence of significant operating parameters, namely pH value, gas flow rate, and absorbent flow rate, on CO2 capture in a bubble column reactor was experimentally explored using NaOH solution. The formation of sodium bicarbonate during the carbonation experiment was confirmed by X-ray diffraction (XRD) and thermal gravimetric analysis (TGA). The experimental results show a CO2 removal efficiency exceeding 95% and a NaHCO3 purity above 94% when utilizing a bubble column reactor. [ABSTRACT FROM AUTHOR]

The hydrothermal treatment of Moroccan coal fly ash (CFA) in a basic medium leads to the selective formation of Na-X zeolite. By fusion with sodium hydroxide in the presence of CFA, the particles are transformed into sodium silicate and sodium aluminate, from which hydrothermal reaction favourably results in the production of a pure Na-X zeolite. A good crystallinity of Na-X zeolite was attained at NaOH:fly ash ratio of 1.2. Their high surface area and pore characteristics make the Na-X zeolite useful for the removal of the model anionic dye RY145 from water. The adsorption efficiency of the synthesised Na-X zeolite was evaluated and compared to raw CFA. Dye adsorption is more significant at acid pH, suggesting that the zeolite surface is positively charged. Kinetic and isotherm models applied to fit the experimental data reveal that the adsorption process is physisorption. It results that zeolite X is an efficient adsorbent for the extraction of dyes. [ABSTRACT FROM AUTHOR]

Compared with traditional cement pastes, geopolymer pastes can effectively alleviate environmental and economic problems caused by the construction industry as they are characterised as low carbon dioxide materials, with energy reduced energy consumption and emissions. However, the mechanical properties of geopolymer pastes are greatly affected by the composition of the alkaline activators used in their preparation, and existing research results on this influence is not consistent. In this study, the effects of alkaline activators composed of varying concentrations of sodium hydroxide (NaOH) solution under standard curing conditions on the mechanical properties and material characteristics of geopolymer pastes made with fly ash and slag were investigated. Under standard curing conditions, the mechanical properties of the geopolymer pastes increased with an increase of sodium hydroxide solution (SHS) concentration in the alkaline activator. The use of alkaline activator with 16 M SHS led to the greatest flexural and compressive strengths of the geopolymer pastes at 28 days, reaching values of 5.43 MPa and 39.13 MPa, respectively. Increasing the SHS concentration in the alkaline activator promoted the production of gel products such as N-A-S-H, which formed a dense microstructure and led to higher mechanical properties. [ABSTRACT FROM AUTHOR]

Dechlorination is a crucial strategy for archeological bronze stabilization to resist corrosion induced by cuprous chloride (CuCl). Conventional samples, either archeological or simulated ones, have deficiencies in revealing dechlorination mechanisms for their complex rust layers and difficulties in quantifying chlorine content. In this work, samples with fixed chlorine amounts were prepared by compressing method to solve overcomplicated and unquantifiable problems. Then, patina profiles and desalinization solutions were analyzed to revisit the dechlorination mechanism across varying solution concentrations and current densities after dechlorination treatments. Results indicate that the sodium hydroxide (NaOH) desalinization method is achieved by converting CuCl to trihydroxychloride (Cu2(OH)3Cl). However, this transformation leads to an expansion of the CuCl layer, nearly doubling the CuCl layer thickness at the current density of 25 μA/cm2. Dechlorination solution measurements provide information on quantifying chlorine removal and dechlorination progress. Theoretically, the endpoint (c0) for the NaOH dechlorination method is supposed to be a chloride ion concentration of 358.2 ppm. As the NaOH solution concentrations vary from 10−6 to 10−2, CuCl dechlorination progress (Et=24h) calculations are at about 3% to 6% at 24 h. Applying the current significantly improves the effectiveness of dechlorination at 2.5 μA/cm2. However, the chloride ion concentration in the solution starts to decrease after reaching a current density of 12.5 μA/cm2, even dropping to 12.07 ppm at 25 μA/cm2. According to a theoretical analysis, chlorine evolution during electrolytic processes would be responsible for this phenomenon. [ABSTRACT FROM AUTHOR]

Recycling the metals found in spent batteries offers both environmental and economic benefits, especially when extracted and purified using environmentally friendly processes. Two basic leaching agents were tested and compared: ammonium hydroxide (NH4OH) and sodium hydroxide (NaOH). Using NH4OH 4 M at 25 °C, 30.5 ± 0.7 wt. % of zinc (Zn) was dissolved for a solid/liquid (S/L) ratio of 1/10 (g of black mass (BM)/mL of solution); meanwhile, with NaOH 6 M at 70 °C, and an S/L ratio of 1/5 (g of BM/mL of solution), 69.9 ± 2.8 wt. % of the Zn initially present in the BM of alkaline batteries was leached. A virtual representation of the experimental data through digital twins of the alkaline leaching process of the BM was proposed. For this purpose, 90% of the experimental data were used for training a supervised learning procedure involving 600 different artificial neural networks (ANNs) and using up to 12 activation functions. The application was able to choose the most suitable ANN using an ANOVA analysis. After the training step, the network was tested by predicting the outputs of inputs that were not used in the training process, to avoid overfitting in a validating process with 10% of the data. The best model was employed for estimating the degree of leaching of different metals that can be obtained from BM, obtaining a data deviation of less than 10% for highly concentrated compounds such as Zn. [ABSTRACT FROM AUTHOR]

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

We report the successful synthesis of hydrophilic thioester-containing polyacrylamide copolymers by the RAFT and free-radical copolymerisation of dibenzo[c,e]oxepane-5-thione with either acrylamide or N-isopropylacrylamide. These copolymers efficiently degrade in aqueous solutions of sodium hydroxide, isopropylamine, L -cysteine, and household bleach, reducing the weight-average molecular weight by up to ∼90%. [ABSTRACT FROM AUTHOR]

Starch‐based biocomposites exhibit great potential as an alternative to fossil‐based materials. This work focused on investigating the properties of the starch‐based biocomposite reinforced by cellulose nanofibers derived from sugarcane bagasse (SCB). The sodium hydroxide (NaOH) concentration was varied from 4%, 8%, and 12% wt/vol for the SCB extraction process. The obtained nanofibers, respectively called SCBNF4, SCBNF8, and SCBNF12, were characterized by various techniques prior to being incorporated into modified starch (MS). The effects of the type and amount of SCBNF on the mechanical properties, thermal behavior, optical transparency, and moisture absorption of the biocomposite films were examined. All SCBNF samples had a cellulose type I structure with a diameter on the nanometer scale, regardless of the NaOH concentration. The SCBNF's diameter decreased, whereas the crystallinity index increased with increasing NaOH concentration. When incorporated into MS, the higher SCBNF loading resulted in enhancements of mechanical properties and resistance to moisture absorption with the sacrifice of optical transparency. The biocomposite filled with SCBNF12 exhibited better overall performance at a certain filler loading due to the greater filler‐polymer interaction. The benefits of greater strength, light weight, and eco‐friendliness of the developed biocomposites make them suitable for many applications, including packaging. Highlights: Diameter and crystallinity index of SCBNF were governed by NaOH concentration.Adding SCBNF to MS greatly improved the biocomposite's mechanical properties.SCBNF12 showed the highest biocomposite's overall performance.The maximum strength was achieved at 1 phr of SCBNFs.The addition of SCBNFs reduced water and moisture absorption. [ABSTRACT FROM AUTHOR]

Backfill materials are used in underground engineering to fill voids and buried excavated parts. In this study, solid waste was utilised as a raw material mixed with different amounts of polypropylene fibres to determine the optimal sodium hydroxide content, water—solid ratio, and fibre content. The uniaxial compressive strength (UCS) of the produced backfill materials was measured, and the interfacial structures were analysed via scanning electron microscopy. The results revealed that the mechanical properties of the backfill materials were influenced in the order sodium hydroxide doping > water—solid ratio > fibre doping. The optimal material composition corresponded to a sodium hydroxide content of 3%, water—solid ratio of 0.28, and fibre content of 5 ‰. The slag produced a C—S–H gel. Meanwhile, the fly ash and gangue contained large amounts of aluminium, which formed hydrated aluminosilicates. The addition of polypropylene fibres reduced the number of internal defects in the backfill structure and increased the UCS. [ABSTRACT FROM AUTHOR]

Current methods for separating critical materials from feedstock solutions remain chemistry- and energy-intensive. We demonstrate the rapid extraction of a pure magnesium phase from seawater via precipitation with sodium hydroxide in a flow-gel device. Our approach is scalable, suitable for high-throughput extraction, and does not rely on specialty chemicals. [ABSTRACT FROM AUTHOR]

This manuscript presents a novel hybrid technique for assessing the geopolymer concrete' properties incorporating recycled concrete aggregates. Named AO-GBDT, this hybrid approach combines the Aquila Optimizer (AO) and the Gradient Boosting Decision Tree algorithm. The primary objective is to reduce errors and predict the optimal strength of RCA geopolymers. The method investigates the interaction of key parameters and prediction values, like sodium silicate and sodium hydroxide to improve the binding materials. AO is specifically utilised for optimising the mixture proportions of RCA geopolymers, while GBDT is used to forecast the compressive strength of the optimised concrete mixtures. Additionally, the effects of fly ash (FA) and ground granulated blast furnace slag (GGBS) on the concrete's hardened and fresh characteristics are investigated. Performance evaluation conducted in MATLAB demonstrates the effectiveness of the proposed system, which is contrasted to existing strategy. The proposed strategy exhibits a root-mean-square error of 1.8, a correlation coefficient (R) of 0.95 and a mean absolute error of 0.9, indicating its superior predictive accuracy and efficacy compared to existing approaches. [ABSTRACT FROM AUTHOR]

This study investigates the field emission characteristics of coated and uncoated graphite fiber tips under high vacuum conditions in the pressure range of 10–6 Pa. A 2 M Sodium hydroxide (NaOH) solution was used in the electrochemical etching procedure to produce an uncoated etched graphite fiber emitter with a diameter of 436.5 nm. An epoxy coating 2301 dielectric material with a thickness of 61 ± 1 nm was used to coat the fiber tip. Field-emitter emission micrographs, current stability, and current-voltage (I-V) characteristics were recorded. Murphy's Good plots were used to examine and analyse the I-V characteristics. An orthodoxy test was performed to evaluate the Murphy Good plots. In the reported results, at low applied voltages, the uncoated graphite fiber emitter passed orthodoxy tests, and generated a steady current with 0.03 µA uncertainty. However, the coated graphite fiber emitter showed an increase in the applied voltage and threshold voltages but had no impact on the sample emission characteristics. [ABSTRACT FROM AUTHOR]

The durability properties of geopolymer mortars prepared using different contents of slag and glass powder (GP) were examined and compared with the properties of Portland cement mortar (PCM). The slag–GP mixes were activated with a 6 M sodium hydroxide solution at a liquid-to-solid ratio of 0.35. The performance of 28-day cured specimens after high-temperature exposure, wetting–drying and freezing–thawing cycles, water slaking, surface abrasion and alkali–silica reaction (ASR) were examined. Scanning electron microscopy was carried out to identify the microstructural changes in the materials. The results showed that an appropriate GP content (10%) enhanced the performance of the slag–GP binary geopolymer and improved its durability. However, ASR expansion was found to increase marginally. The geopolymer specimens achieved higher strength and durability than PCM due to their dense and compact microstructure with significant gel formation. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a versatile biopolymer with significant potential across biomedical, food, and industrial applications. To remove bacterial contaminants, such as protein and DNA, BC pellicles undergo purification, which traditionally relies on harsh alkali treatments, such as sodium hydroxide or strong surfactants, which present environmental concerns. In response, this study evaluates the efficacy of various non-conventional surfactants—both non-biodegradable and biodegradable—as alternatives for BC purification. Among the surfactants tested, sodium cocoyl isethionate (SCI), a mild anionic and biodegradable surfactant, emerged as particularly effective, achieving an 80.7% reduction in protein content and a 65.19% reduction in double-stranded DNA (dsDNA) content relative to untreated samples. However, these advantages were not without additional challenges, such as the appearance of residual surfactants. Given SCI's promising performance and biodegradability, it was further examined in two-step treatment protocols; additionally, sodium dodecyl sulfate (SDS) was also examined as a more traditional anionic surfactant as well as NaOH. For the two-step treatment protocol, BC pellicles were treated with one reagent for 3 h, followed by a second reagent for an additional 3 h. Notably, by using NaOH as the final step in the two-step treatment protocol, residual surfactant was not detected in the FTIR analysis. Overall, this work demonstrates that SCI, in addition to subsequent NaOH treatment, can be used as a surfactant-based approach for BC purification, representing a potential environmentally friendly alternative to traditional surfactant-based approaches for BC purification. [ABSTRACT FROM AUTHOR]

Rare earth acid insoluble slag (REAIS) is a low-level radioactive slag that is stored in most enterprises nowadays. Because of the pressure from negative environmental consequences and stock saturation, it is imperative to reduced dispose of REAIS. In this paper, we propose a sodium hydroxide-assisted low-temperature roasting method for the conversion of barium sulfate in REAIS (approximately 25% of REAIS). And the effects of the mixing method, mass ratio, carbon dioxide flow rate, roasting temperature, and roasting time on the conversion of barium salt were investigated. The results showed that the optimized process, which included a slurry mixing with a REAIS/NaOH mass ratio of 1:1, roasting for 3 h at 425 °C, and a carbon dioxide flow rate of 3 L min−1, produced more than 96% conversion rate of barium salt, 33% efficiency of sodium hydroxide, and 65% reduction rate of REAIS. The efficient conversion of barium salts in the REAIS could lead to the recovery of barium resources. This has made a significant contribution to REAIS reduction, lessening the impact on the environment and public health, and has provided a directional guideline for the reduction of REAIS emissions. [ABSTRACT FROM AUTHOR]

To investigate the effects of repeated sodium hypochlorite stress on the resistance of Salmonella enterica Serovar Enteritidis (S. Enteritidis) LWCC1051. LWCC1051 was exposed to Trypticase Soy Broth (TSB) containing sodium hypochlorite concentrations of 9 mmol/L, 10 mmol/L, and 11 mmol/L. After 13 repeated transfers and incubations, three sodium hypochlorite resisted LWCC1051 strains were obtained. The D-values and colony morphologies of these strains were assessed. Their survival rates at 60 °C, 65 °C, 70 °C, 75 °C, and − 20 °C were determined and lethality curves at these temperatures were fitted using the Weibull model. Additionally, the Minimal Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) for these strains in various chemicals, including malic acid, citric acid, ascorbic acid, acetic acid, lactic acid, hydrochloric acid, sodium hydroxide, potassium hydroxide, calcium chloride, sodium chloride, and potassium chloride were ascertained. Sodium hypochlorite concentrations of 9 mmol/L, 10 mmol/L, and 11 mmol/L in TSB induced sodium hypochlorite resistance in S. Enteritidis. D-value increased with the frequency of stress exposure. Higher concentrations of sodium hypochlorite resulted in greater D-values and noticeable differences in colony morphologies. The Weibull model accurately represented the temperature resistance curves of LWCC1051 at the specified temperatures. With increasing sodium hypochlorite stress, both high and low-temperature resistances of LWCC1051 improved. Furthermore, under acetic acid stress, the MIC and MBC values of LWCC1051 strains, post exposure to 9 mmol/L, 10 mmol/L, and 11 mmol/L sodium hypochlorite, doubled. Sodium hypochlorite stress enhances the cross-resistance of LWCC1051 to high temperature, low temperature, and acetic acid treatments. [ABSTRACT FROM AUTHOR]

Denver Water used a variety of water treatment and chemistry approaches to resolve fluctuating pH levels and meet its Lead and Copper Rule variance requirements. [ABSTRACT FROM AUTHOR]

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

This study presents the results of experimental determination and theoretical calculations of the thermal effect of aluminum dissolution in alkaline solutions accompanied by hydrogen evolution. The experiments were conducted using an EK1 calorimeter, with temperature measurements recorded every 10 seconds. Potassium hydroxide solutions with concentrations ranging from 0.5 to 5 mol/L were utilized. It was demonstrated that the temperature variation curves over time, the temperature dynamics at different solution concentrations, and the aluminum dissolution rate exhibit an S-shaped profile. The rate of aluminum dissolution in aqueous alkaline solutions depends on the KOH concentration. As the KOH concentration increases from 0.5 to 2 mol/L, the thermal effect of the reaction rises. Further increasing the alkali concentration to 5 mol/L results in almost no change in the thermal effect. The thermal effect of aluminum dissolution in 3-5 mol/L sodium hydroxide solutions was found to be 1300 J/g. The experimentally determined thermal effect falls within the range of values calculated from thermodynamic data (from 1165 to 1528 J/g). The results obtained in this study can be applied to the development of relatively low-cost hydrogen production technologies. [ABSTRACT FROM AUTHOR]

Drylands in Brazil have been exploring sisal (Agave sisalana) as an essential source of income. However, the solid residues generated because of this activity still need suitable destinations; therefore, research has been carried out to transform them into added-value products. Therefore, the present study evaluated the potential of sisal or agave solid residue as a precursor feedstock for second-generation ethanol production. Acid and acid–alkaline pretreatments were carried out on sisal residues to enrich the biomass with cellulose and maximize enzymatic digestibility. Second-generation ethanol production was carried out using Semi-simultaneous saccharification and fermentation (SSSF). Regardless of catalyst dosage and incubation time, oxalic acid pretreatments generated samples with a similar chemical composition to those pretreated with sulfuric acid. However, samples pretreated with oxalic acid showed lower enzymatic digestibility. Samples pretreated with oxalic acid and sodium hydroxide obtained 14.28 g/L of glucose and cellulose conversion of 79.1% (at 5% solids), while 21.49 g/L glucose and 91.2% of cellulose conversion were obtained in the hydrolysis of pretreated samples with sulfuric acid and sodium hydroxide combined pretreatments. The pretreatment sequence efficiently reduced cellulase dosage from 20 to 10 FPU/g without compromising sugar release. SSSF achieved maximum production of 40 g/L ethanol and 43% ethanol conversion using 30% solids and gradually adding biomass and cellulases. [ABSTRACT FROM AUTHOR]

Mild conditioned, second-life ternary nickel–cobalt–manganese (NCM) black powder regeneration from spent lithium-ion batteries' (LIBs) black powder mixture was demonstrated after mild conditioned p-toluenesulphuric acid (PTA)-assisted wet leaching. The NCM ratio was tailored to several combinations (333, 523, 532, and 622) by adding a suitable amount of metal (Ni, Co, Mn)-sulphate salt to the leachate. Regenerated NCM was obtained by co-precipitation with sodium hydroxide pellets and ammonia pH buffering solution, followed by lithium (Li) sintering under ambient air and size sieving. The obtained regenerated NCM powder was used for the energy storage materials (ESM) in coin cell (Li half-cell, CR2032) evaluation. Systematic characterization of regenerated NCM showed that the NCM ratio was close to the target value as assigned in the tailored process, and regenerated 622 (R622) exhibited strong activity in CR2032 coin cell testing among all four ratios with a maximum discharge capacity of 196.6 mAh/g. [ABSTRACT FROM AUTHOR]

This paper studies the extraction of alumina from kaolin through an acidic leaching process. The kaolin sample used in this study was taken from the Zonuz kaolin mine (Iran Porcelain Industries Company) at particle sizes smaller than 150 microns. Calcination of the kaolin sample was conducted at 700 ºC for 2 hours. Aluminum was leached from calcined kaolin with an H2SO4 acid solution. Temperature and time of leaching, acid concentration, and liquid-to-solid ratio were investigated as leaching parameters. The optimal leaching conditions were considered at 90 °C, 3 hours duration, 2.5 M acid concentration, 7 ml/g liquid-to-solid ratio, and 600 rpm stirring speed, and under these conditions, aluminum leaching recovery was obtained at 94.87%. To remove the iron impurity that is transferred to the solution during leaching, the pregnant leaching solution was purified. Purification was done by solvent extraction with an organic phase containing D2EHPA as an extractant and oil as a diluent, iron removal was achieved at 88.71%. By precipitating the aluminum hydroxide from a solution of aluminum sulfate with sodium hydroxide followed by calcination of the produced aluminum hydroxide at a temperature of 1200 °C for 2 hours, alumina with a purity of 97% was produced. The total recovery of alumina obtained from the studied kaolin under optimal conditions was 89.46%, which is desirable. [ABSTRACT FROM AUTHOR]

Tungsten carbide (WC-Co) with a cobalt binder has been widely used in industrial application. Through their high wear resistance and hardness, which make it a challenge to machine. Electrochemical discharge machining (ECDM) is a newly developed hybrid technique used to machine conductive and nonconductive materials. Tungsten carbide machining is an area that needs more investigation. In this study, different types of electrolytes have been tested in the electrochemical machining of tungsten carbide. It has been concluded that tungsten carbide was successfully machined with electrolytes that were either neutral salts or a combination of neutral salts and hydroxides, the highest material removal rate achieved was (0.09250 g/min), and the average surface roughness achieved in this work was measured at (Ra 0.9275 µm). However, deposition took place on the surface of machined tungsten carbide when the samples were treated with sodium hydroxide and potassium hydroxide. EDX analysis of successfully machined tungsten carbide samples reveal the presence of carbon (C) due to diffusion from the base material and oxygen (O), most likely due to oxidation brought on by the high temperatures utilized. Scanning electron microscopy confirmed that the machined surfaces had craters, pores, restricted microcracks, and re-deposited melt particles, among other things. [ABSTRACT FROM AUTHOR]

Starch from jackfruit seeds shows potential for use in food production processes with high starch content. Modification of jackfruit seed starch to increase the resistant starch content makes it a promising candidate for prebiotics in the food industry. Carboxymethylation can provide benefits for starch utilization in improving starch functional properties such as solubility, viscosity, and resistant starch content. This study chemically modified starch through carboxymethylation at different concentrations of sodium hydroxide to investigate the effect of carboxymethyl substitution on the digestible properties of the starch. Carboxymethylation exhibited a high degree of substitution from 0.28% to 0.57% as a function of the concentration of sodium hydroxide (5–10 wt%). The treatment enhanced the swelling, water solubility, and water/oil absorption. The resistant starch content increased from ~ 21 to ~ 39.67%. However, the high degree of substitution showed structural deformation of the starch granules with a decrease in crystallinity from about 35 to 1% by SEM and XRD. The degree of carboxymethyl substitution increased resistant starch content, reduced rapidly digestible starch, and had negligible impact on slowly digestible starch. Jackfruit seed starch treated with 10% by weight of NaOH was the optimal value that increased carboxymethyl substitution to 0.57% and resistant starch content to ~ 40%. This concentration was also optimal for the functional properties of starch with the highest values of swelling degree (~ 27 g/g), water solubility (~ 50%), freeze–thaw stability (~ 20% of syneresis after 4 freeze–thaw cycles), and oil and water absorption (150% of oil absorption and 180% of water absorption). [ABSTRACT FROM AUTHOR]

Dry‐gel conversion (DGC), which directly converts zeolite gel into crystals by vapor, is considered a promising method for reducing amounts of zeolite precursors and easily controlling crystallization. Synthesis of MFI zeolites employing the DGC method with different amounts of tetrapropylammonium bromide (TPABr) and sodium hydroxide (NaOH) was studied to investigate the effect of TPABr and NaOH on the crystallization of MFI zeolite, with the optimal condition for synthesis found to be 0.05625 for both NaOH/SiO2 and TPABr/SiO2. Additionally, carbon black (CB) was added onto the MFI zeolite precursor gel as a hard template to generate mesopores into zeolite frameworks. The resultant MFI zeolite with CB synthesized by the DGC method showed mesoporosity, with pore size distribution similar to the particle size of CB. However, the conventional hydrothermal method could not generate mesopores in MFI zeolite due to the separation of zeolite crystals from CB templates during crystallization. [ABSTRACT FROM AUTHOR]

Patient: Male, 23-year-old Final Diagnosis: Mycobacterium marinum infection Symptoms: Multiple sporotrichoid skin lesions Clinical Procedure: -- Specialty: Infectious Diseases Objective: Unknown etiology Background: Mycobacterium marinum is a slow-growing non-tuberculous mycobacterium that is known to cause skin and soft tissue infections, even in healthy patients, and is commonly associated with fish and aquatic environments. Case Report: A 23-year-old man working in aquarium management presented with a chronic progression of multiple skin nodules on his right forearm and thumb. The patient was referred from the Dermatology Department to the Outpatient Clinic due to suspected skin tuberculosis, as indicated by a positive T-SPOT.TB test. A second excisional biopsy tested positive for M. marinum via PCR sequencing by the National Institute of Infectious Diseases, confirming the diagnosis. The initial treatment consisted of rifabutin at 300 mg/day and clarithromycin at 800 mg/day. However, due to liver dysfunction, the regimen was changed to moxifloxacin at 400 mg/day and rifabutin. Moxifloxacin was discontinued due to nausea. Finally, the treatment was adjusted to linezolid at 1200 mg/day and clarithromycin. The patient's skin condition improved, with the nodular lesions showing a trend toward resolution. Culturing is time-consuming, and the sensitivity can be reduced when using N-acetyl-l-cysteine--sodium hydroxide in the pre-treatment process; therefore, caution with its use is necessary. Pathological examination can initially show inflammatory changes, and granulomatous lesions with caseous necrosis are not always present. Antibiotics such as rifampicin, rifabutin, moxifloxacin, and clarithromycin are used, but there is scant evidence for treatment regimens, often resulting in prolonged monotherapy or combination therapy. Conclusions: In cases presenting chronic lesions resembling multiple sporotrichoid forms, repeated biopsies are crucial due to the challenges associated with culturing. [ABSTRACT FROM AUTHOR]

This paper explores the use of a ternary blended geopolymer concrete (TBGPC) incorporating metakaolin (MK), pond ash (PA), and Alccofine 1203 (AF). Three combinations of MK (25%, 50%, and 75%) with varying proportions of PA and AF were prepared, validating against M30 grade cement concrete (CC). TBGPC was prepared with an 8 molarity sodium hydroxide, sodium silicate to sodium hydroxide ratio of 2.0, liquid to binder ratio of 0.5, and an ambient curing mode. For CC, a water to cement ratio of 0.42 and water curing mode were adopted. The mechanical properties and durability behavior of TBGPC and CC specimens were evaluated through compressive strength, rapid chloride penetration test, permeability test, sorptivity test, and water absorption test. The M50P35A15 mix demonstrated remarkable compressive strength improvements, showing a 203% increase over the CC mix at 1 day and 250% by 3 days. This trend continued with a 155% increase at 7 days, 68% at 28 days, and 52% at 90 days, consistently outperforming the CC mix. Additionally, microstructure characteristics of the M50P35A15 mix were analyzed through SEM studies, providing validation for the observed strength development. Notably, M50P35A15 mix demonstrated substantially higher early and later strength gain. This enhancement in strength was attributed to the gradual densification of the microstructure over time and the formation of additional NASH and CASH gel in M50P35A15 mix. At 28 days, the M50P35A15 mix exhibited excellent durability characteristics, with a Coulomb value of 1008, permeability of 10 mm, sorptivity of 0.45 mm/√min × 10−4, and water absorption of 1.07%. This study demonstrates the potential of MK, PA, and AF as viable materials for sustainable geopolymer concrete, offering a low-carbon alternative to traditional cement concrete with superior strength and durability aspects. [ABSTRACT FROM AUTHOR]

In this study, several methods for a novel binderless technology were explored, the effects of treatment conditions on the adhesive performance were examined and the surface was characterized during adhesion. The method entailed a three-step process for bonding solid wood, which involved immersion in sodium hypochlorite–containing treatment solutions, surface scratching, and drying with pressing. Various treatment conditions were investigated, including solution types, immersion durations, scratch treatment materials, and pressing methods. The resulting shear strength was 9.7 MPa, which is well above the Japanese Agricultural Standards value for laminated wood (6 MPa). In this method, the specimens were immersed in a bleach solution containing a surfactant for 16 h, followed by pressurization at 1 MPa for 24 h at 60 ℃ using a pressure-controlled press. Around the bonding area in the specimens, the cells in the immersed area were significantly compressed, and the aldehyde groups of the coniferyl aldehyde in the lignin were denatured or lost. Based on these findings, a new binderless technology was developed for solid wood without a high-temperature, high-pressure pressing step. [ABSTRACT FROM AUTHOR]

Modification of polyester (poly(ethylene terephthalate)) fabric by grafting with poly(methacrylic acid) was studied. The objective was to improve the hydrophilicity of polyester and, hence, its water uptake. The modified polyester fabrics were characterized by gravimetric method, Fourier transform infrared, dynamic mechanical analysis, and scanning electron microscopy. It was found that grafting of methacrylic acid onto polyester fabrics could be effected by radical reaction using benzoyl peroxide as radical initiator. Swelling of polyester fabric with benzyl alcohol was also found to be necessary for grafting to occur. The parameters which affected the modification reaction were initiator concentration, monomer to fabric ratio, reaction temperature, and reaction time. In addition, it was shown that the percentage uptake of moisture of the modified fabric (1–4.6%) increased with increase in the extent of grafting (5–32%). The modified fabric tended to be stiffer than the unmodified fabric, but they could be softened by controlled treatment with aqueous solution of sodium hydroxide. The stability of the modified polyester fabric, however, was found to decrease with increase in the extent of modification (high monomer to fabric ratio) and increasing concentration of sodium hydroxide solution. Thus, careful control of sodium hydroxide treatment process was necessary to prevent deterioration of the modified polyester fabric. [ABSTRACT FROM AUTHOR]

Cement Asphalt Mortar (CAM) is widely applied in infrastructure, particularly in railways, bridge expansion joints, and pavements, due to its combination of cement's load-bearing capacity and asphalt's flexibility. Conventional CAM formulations, however, often encounter challenges such as extended setting times, high shrinkage, and limited durability under extreme environmental conditions. This study addresses these limitations by integrating bio-oil and polymer additives to enhance both the sustainability and performance of CAM mixtures. CAM mixtures were evaluated with cement-to-asphalt emulsion (C/AE) mass ratios of 75:25 and 50:50, incorporating bio-oil contents of 2% and 4% by mass and latex–acrylic polymer proportions ranging from 1% to 2% by mass. The optimized mix design, with a 75:25 cement-to-asphalt emulsion (C/AE) mass ratio, 2% bio-oil, and 1.5% polymer, improved flowability by 25%. This formulation achieved a flow diameter of approximately 205 mm and reduced the flow time to 72 s. Compressive strength tests indicated that this formulation reached an early-stage strength of 10.45 MPa (a 20.8% improvement over the control) and a 28-day strength of 24.18 MPa. Thermal stability tests at 45 °C demonstrated that the optimized CAM retained 86.6% of its compressive strength, compared to a 25% reduction in unmodified mixtures. Chemical resistance assessments in 5% sulfuric acid and 5% sodium hydroxide solutions showed strength retention of 95.03% and 91.98%, respectively, outperforming control mixtures by 17% and 13%. SEM examination revealed a dense, cohesive microstructure, reducing shrinkage to 0.01% from 0.15% in the control. These findings underscore the potential of bio-oil and latex–acrylic polymers to improve the performance and sustainability of CAM mixtures, making them well suited for resilient, rapid-setting infrastructure applications. [ABSTRACT FROM AUTHOR]

To meet the needs of consumers for high-quality textiles, the blended fabrics gradually become the mainstream of the market. However, developing the union dyeing blended fabrics in finished fabrics is still challenging. In this paper, different mass fractions of urea, caustic soda, ethylenediamine, and ethylenediamine + urea + water fiber swelling agent were used to modify the blended fabric. The barium values for the two fibers, adsorption swelling time and temperature were measured. The results showed that ethylenediamine + urea + water displayed the best combination candidates for the union dyeing of the blended fabric, which had a certain degree of elimination of crystallinity on cotton fibers. The optimal swelling process parameters of ethylenediamine:urea:water were 75:15:10, the temperature is 30 °C, and the time is 90 min. Under this process, washing under different conditions had a significant effect on the union dyeing of the blended fabric. After the fabric was washed with alcohol, the cotton fiber configuration also changed from cellulose type I to cellulose type I (12) + EDA-I (88), with a high degree of transformation and a high degree of decrystallization (30.98%). The modal fiber configuration changed from cellulose type II to cellulose type II (77) + EDA- II (23), with a low degree of transformation and a low degree of decrystallization (8.83%).Finally, the union dyeing values were increased from 0.4 ~ 0.5 to 0.85 ~ 1.1 without.the change of style and feel of the blended fabric. Notably, the breaking strength of the blended fabrics was reinforced. This work has significant implications for the development of high-quality cotton/modal blended fabrics with high union dyeing and fixation rate. [ABSTRACT FROM AUTHOR]

The aim of the study was to utilize the waste generated from Bullseye (Priacanthus hamrur) fish processing to recuperate proteins. Considering the cost-effectiveness, versatility, and color improvement after the pH shift method, proteins from this waste were extracted by the pH shift method using hydrochloric acid and sodium hydroxide. The properties of extracted proteins were studied in detail. During the protein solubility measurement, maximum solubilization was found at pH 3.0 (13.10 mg/mL) on the acidic side and pH 11.0 (14.25 mg/mL) on the alkaline side with a total yield of 51.62 ± 0.23 and 45.42 ± 0.29 (%), respectively. The process variables tested in this study showed a significant effect on protein solubility (p < 0.05). The protein content of the isolates extracted from the waste was 23.80 ± 0.49 and 22.48 ± 0.39% for acid and alkali processed isolates, which was significantly higher than the mince (19.46 ± 0.67%). pH shift processing of Bullseye proteins caused a significant reduction in its pigments, lipids, and myoglobin content (p < 0.05). Proteins extracted using alkali had significantly higher values for foaming stability, water holding capacity, and emulsion capacity than proteins extracted using acid. An overall assessment indicated that protein isolates obtained using alkali extraction were better in terms of textural attributes, gelling ability, and amino acid profile than protein isolates extracted using the acid process. [ABSTRACT FROM AUTHOR]

Researchers and scientists have focused on the development and future opportunities of flexible sensors in food, environment and defense fields. In this study, we propose a flexible substrate material‐based nanofibril cellulose empty fruit bunch (NEFB)‐reinforced thermoplastic polyurethane (TPU) blend nanocomposite for flexible substrate materials. Untreated and treated nanofibril cellulose samples of empty fruit bunch (NEFB, 0, 1, 2, 3, 4 wt. %) were treated with 6 wt.% sodium hydroxide (NaOH) and subjected to internal Brabender mixer followed by a hot‐pressing machine. The density and tensile and dynamic mechanical properties of the nanocomposites were investigated for the treated and untreated samples. Tensile properties were characterized using a Universal Testing Machine, and the fracture mechanism after post‐tensile testing was determined by scanning electron microscopy (SEM). Increasing the content of untreated NEFB/TPU improved the tensile strength compared with 6% treated NEFB/TPU blend nanocomposites. Incorporating the nanofibril cellulose of empty fruit bunch at 2% into the TPU blend nanocomposites significantly increased E′, E" and Tg compared with other formulations. Highlights: Nanocellulose derived from plants is considered a promising material for flexible substrates in electronics due to its robust mechanical properties and eco‐friendliness.Malaysia's abundant empty fruit bunch (EFB) resources make it a possible source of nanocellulose, which improves the properties of polymers.The effect of sodium hydroxide (NaOH) treatment on the compatibility of EFB‐derived nanocellulose with polymer matrices was investigated.The addition of nanocellulose, particularly at a concentration of 1%, significantly increases the tensile strength of thermoplastic polyurethane nanocomposites, whereas 6% NaOH treatment has no effect.Dynamic mechanical analysis reveals high storage modulus at 2% nanofibril cellulose empty fruit bunch (NEFB) and energy dissipation at 4% NEFB as well as enhanced interfacial bonding at 1% NEFB. [ABSTRACT FROM AUTHOR]