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In this study, LiNaCO3‐ and (Li‐Na‐K)2CO3‐based porous carbon composites were synthesized from terephthalic acid, lithium hydroxide, sodium hydroxide, and potassium hydroxide at different calcination temperatures. These composite materials were characterized with X‐Ray diffraction, scanning electron microscopy, and nitrogen adsorption and desorption. According to their CO2 capture performance measured, LiNaC‐700 °C had the largest CO2 adsorption capacity of 66 mg CO2 g−1, while the CO2 capture capacity of other materials doped with three metal ions was only up to 8.57 mg CO2 g−1. Additionally, the CO2 adsorption capacity of each adsorbent was significantly higher than the N2 adsorption capacity, showing their high CO2 adsorption selectivity. Lithium‐containing carbonate‐based porous carbon materials (LiNaCO3‐ and (Li‐Na‐K)2CO3‐based porous carbon could effectively capture CO2 with excellent reproducibility. [ABSTRACT FROM AUTHOR]

The sagger, primarily composed of aluminum-silicon, serves as an essential vessel in the sintering process of ternary lithium battery anode materials (LiNi x Co y Mn 1-x-y O 2 , LNCM). However, the acidic oxide SiO 2 in the sagger material readily reacts with Li 2 O in the cathode material, forming substances such as LiAlO 2 or LiAlSiO 4 , resulting in volume expansion, which makes the sagger spalled and damaged. In this study, β-Al 2 O 3 –MgAl 2 O 4 multiphase materials with excellent alkali resistance were prepared using the high-temperature solid-state method. The effects of anhydrous sodium carbonate content and heat treatment temperature on the properties of the composites were investigated, and the thermal shock resistance of the specimens was evaluated by the water-rapid-cooling method, as well as the LNCM corrosion resistance of the specimens was evaluated by the static crucible method. The results showed that the overall performance of the specimens was the best at a anhydrous sodium carbonate content of 6 wt%, with a compressive strength of 57.50 MPa and a flexural strength of 42.49 MPa after firing at 1600 °C for 4 h. The strength retention of the specimens was 33.21 % after one thermal shock at a thermal shock temperature of 900 °C. The specimens showed excellent resistance to erosion as there were no obvious erosion traces on the surface of the specimens after undergoing five cycles of erosion. [ABSTRACT FROM AUTHOR]

Slaked lime was used to synergize with sodium carbonate to activate the slag. Experimental studies were carried out to investigate the effect of the proportion of activator on its workability and mechanical properties. The hydration products, microstructure changes, and strength enhancement mechanism were also explored by isothermal conduction calorimetry (ICC), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscope (SEM) tests. The results show that with the increase of slaked lime doping, the compressive strength increases and then decreases, the fluidity gradually decreases, and the setting time decreases and then increases. The maximum 7- and 28-day compressive strengths were 24.1 and 30.2 MPa at 6% slaked lime dosage, which were 4.8 times higher than those at 0% dosage. This is mainly due to the fact that the reaction products of slaked lime and sodium carbonate can promote the alkali activation reaction, in addition to the fact that higher Ca2+ in the system is favorable to promote C─ (A)─ S─ H generation. However, when the dosage of slaked lime is greater than 8%, the hydrated gel in the system decreases and precipitates more square flakes of Ca(OH)2 , which reduces the interlayer bonding of the hydrated gel, thus reducing the strength. The slaked lime admixture can effectively promote the internal Si and Al dissolution and condensation of slag, improve the rate of hydration reaction, and promote the generation of hydration gel C─ (A)─ S─ H, so that the alkali-activated slag matrix is denser and the strength is improved. [ABSTRACT FROM AUTHOR]

The utilization of calcium carbide residue (CCR) to activate solid wastes can effectively promote sustainable development. This paper explores adding sodium carbonate (Na2CO3) to CCR activators to improve the early reactivity of alkali-activated materials (AAMs) made from sewage sludge ash (SSA). The research focuses on the effects of Na2CO3 on setting, hardening, mechanical strength, and environmental benefits. The findings indicate that Na2CO3 can shorten the paste' hardening time and significantly enhance the early mechanical properties. The introduction of Na2CO3 accelerates the consumption of CCR during the early phases and facilitates the formation of C-(N)-A-S-H gels. Meanwhile, it can significantly reduce the porosity and refine the pore structure. When the dosage reaches 8%, the total intruded pore volume of the sample decreases to 0.15 mL/g. This activation method reduces energy consumption, CO2 emissions, and costs by 69%, 50%, and over 90%, respectively, making it an efficient, eco-friendly approach to AAM production. [ABSTRACT FROM AUTHOR]

Herein, we report a metal-free, base-promoted route for the synthesis of hybrid molecular scaffolds in which various 1,3-diones and 1,2,4-triazoles are linked by a benzyl bridge. This three-component, one-pot reaction was accomplished by first treating 4-hydroxycoumarin, trans-β-nitrostyrene, and aldehyde hydrazone in the presence of sodium carbonate. Further, this protocol was successfully expanded to other 1,3-diones, such as dimedone and 4-hydroxy-2-quinolone. A broad substrate scope, mild reaction conditions, and the metal and ligand/additive-free approach are the prominent features of this strategy. [ABSTRACT FROM AUTHOR]

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The loss of quality of wolframite concentrates determines the need to improve their processing method that ensures maximum conversion of tungsten into water-soluble wolframate and a reduction in water-soluble impurities. The results of thermodynamic modeling of the sintering of wolframite concentrate with sodium and potassium carbonates indicate a greater efficiency of K2CO3: The reagent consumption required for complete conversion of tungsten into solution decreases from 170% from stoichiometric sintering with Na2CO3 to 110% for K2CO3, as well as the proportion of soluble silicates up to 0.1%. In addition, sintering with K2CO3 is accompanied by the formation of compounds with a higher melting point, preventing melting and coating formation during the process. Mathematical sintering models were obtained by the method of probabilistically deterministic planning of this experiment. Optimal parameters have been determined: The extraction of tungsten into a solution of more than 95% is achieved by sintering with K2CO3 in an amount of 105–110% according to the stoichiometric requirements for the formation of K2WO4, K2MoO4, and K2SO4 at temperatures of 1073–1123 K for 100–120 min. Pilot tests have confirmed the effectiveness of the process. The possibility of sintering a cinder of wolframite concentrate with K2CO3 without the introduction of recycled materials has been established. Sintering under optimal conditions ensures the transition of tungsten to water-soluble tungstate by 97.5%. [ABSTRACT FROM AUTHOR]

The effect of partial whole wheat flour substitution by quinoa flour (QF) and defatted apple seed flour (DASF) on the nutritional, antioxidant and sensory properties of gingerbread cookies was studied. Four cookies were prepare with 10% quinoa flour, and three of them contained DASF in three different ratios: 5%, 10% and 15%. They were compared with a control cookie made from 100% whole wheat flour. To predict the functionality of composite flours, the assessment of their technological properties was conducted. Water holding capacity increased, but oil holding and swelling capacity did not change by the addition of DASF to gingerbread cookies. Solvent retention capacity tests revealed an increase in retention of water, lactic acid and sucrose solutions while retention of sodium carbonate decreased by the addition DASF to composite flours compared to the control. Proximate composition analysis suggested that the use of DASF increased lipid and crude fibre content in 15% DASF cookies while protein, ash, total carbohydrates and energy values were unchanged in all tested samples. Analysis of total phenolic, flavonoid and dihydroxycinnamic derivative content in gingerbread cookies extracts indicated that phenolic acids were the main extract constituents and mostly contributed to their antioxidant properties. Antioxidant tests showed that enrichment of gingerbread cookies with DASF improved their antioxidant properties, especially DPPH radical scavenging activity. Sensory analysis revealed that the DASF and quinoa enriched gingerbread cookies were in the category of excellent quality (overall sensory quality 4.91). [ABSTRACT FROM AUTHOR]

To study the effectiveness of dry water material in suppressing oil pool fires, the experimental platform of liquid fuel fire extinguishing was built, and the effectiveness test was carried out. The effect of releasing pressure on dry water suppressing oil pool fires of different sizes was analyzed, and the effectiveness of dry water extinguishing on polar and non-polar liquid fuel was studied. The inhibition efficiency and mechanism of dry water modified by two kinds of metal sodium salt on oil pool fires were revealed. The results show that the release pressure of 0.6 MPa is the most effective for extinguishing the oil pool fire. For methanol, ethanol, and n-heptane liquid fuels, dry water has the highest extinguishing efficiency. Among modified dry water, sodium carbonate dry water is better in fire extinguishing efficiency, while sodium acetate dry water is poor; by comparing the theoretical critical parameters and experimental values, it can be seen that the physical fire extinguishing mechanism of dry water on oil pool fire mainly includes cooling, oxygen isolation and air dilution, among which the cooling effect of fire plume and fuel surface is the dominant physical fire extinguishing mechanism. [ABSTRACT FROM AUTHOR]

Biofuel can be generated by different organisms using various substrates. The green alga Chlorococcum humicola OQ934050 exhibited the capability to photosynthesize carbonate carbon, maybe via the activity of carbonic anhydrase enzymes. The optimum treatment is C:N ratio of 1:1 (0.2 mmoles sodium carbonate and 0.2 mmoles sodium nitrate) as it induced the highest dry mass (more than 0.5 mg.mL−1). At this combination, biomass were about 0.2 mg/mL−1 carbohydrates, 0.085 mg/mL−1 proteins, and 0.16 mg/mL−1 oil of this dry weight. The C/N ratios of 1:1 or 10:1 induced up to 30% of the Chlorococcum humicola dry mass as oils. Growth and dry matter content were hindered at 50:1 C/N and oil content was reduced as a result. The fatty acid profile was strongly altered by the applied C.N ratios. The defatted leftovers of the grown alga, after oil extraction, were fermented by a newly isolated heterotrophic bacterium, identified as Bacillus coagulans OQ053202, to evolve hydrogen content as gas. The highest cumulative hydrogen production and reducing sugar (70 ml H2/g biomass and 0.128 mg/ml; respectively) were found at the C/N ratio of 10:1 with the highest hydrogen evolution efficiency (HEE) of 22.8 ml H2/ mg reducing sugar. The optimum treatment applied to the Chlorococcum humicola is C:N ratio of 1:1 for the highest dry mass, up to 30% dry mass as oils. Some fatty acids were induced while others disappeared, depending on the C/N ratios. The highest cumulative hydrogen production and reducing sugar were found at the C/N ratio of 10:1. [ABSTRACT FROM AUTHOR]

The current work introduces novel and low-cost AgNSs-A@CGGs and CuNRs-A@CGGs photoanodes for the photoelectrochemical (PEC) water-splitting reaction. The photoanodes were fabricated by anodizing commercial galvanized grids(A@CGGs) in the sodium carbonate solution followed by deposition of Ag or Cu through a simple electroless substitution. Surface studies showed that AgNSs-A@CGGs and CuNRs-A@CGGs photoanodes have a unique morphology including Ag nanospheres (AgNSs) and Cu worm-like nanorods (CuNRs) with huge surface area. The UV-VIS diffuse reflectance spectra (DRS) of AgNSs-A@CGGs and CuNRs-A@CGGs photoanodes displayed the lower band gap energies of 2.4 eV, and 2.83 eV respectively, which compared to 3.91 eV for the A@CGGs, showing excellent photoanodic behavior for AgNSs-A@CGGs and CuNRs-A@CGGs photoanodes. Investigations of photoelectrochemical water-splitting under visible light irradiation showed that the production amount of H 2 from AgNSs-A@CGGs and CuNRs-A@CGGs photoanodes was about 18570 and 6895 μmol h−1 cm−2 respectively. Moreover, AgNSs-A@CGGs showed 15.27 and 5.0 times higher photoconversion efficiency than CGGs and A@CGGs respectively. In this study, the introduced photoanode grids are expected to be used as cheap and industrial photoanodes for PEC water-splitting and hydrogen gas production. [Display omitted] • Ag nanospheres and Cu worm-like nanorod structures were developed using electroless substitution. • AgNSs-A@CGGs and CuNRs-A@CGGs showed outstanding photoelectrochemical activity. • The extremely high surface area was a factor contributing to this excellent performance. • The fabricated AgNSs-A@CGGs exhibited favorable photoanodic stability in hydrogen production. [ABSTRACT FROM AUTHOR]

In the present study, with a view to decreasing the inherent fire risk associated with the usage of wood, the flame-retardant efficacies of some additives for wood samples were investigated. The additives included: 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), triphenylphosphine (TPP), diammonium hydrogen phosphate ((NH4)2HPO4) and sodium carbonate (Na2CO3). The test samples incorporating the flame-retardant additives were primarily evaluated by thermo-gravimetric analysis (TGA). It was found that the presence of DOPO imparted some beneficial effects, especially, in terms of increased energetic needs for the second-stage decomposition of the lingo-cellulosic material, coupled to an enhanced production of char residues. However, with the other additive systems, such as TPP, Na2CO3 and (NH4)2HPO4, the flame-retardant effect seemed to arise from increased char production with a concomitant effect on the energetic requirements for the decomposition pathways, especially, at a high temperature. In terms of to the conversion degrees, for samples PFC2, PFC3 and PFC4, stage one was found to extend over the conversion range of 0 ≤ α ≤ 0.65, corresponding to temperatures from 30 to 350 °C. In contrast, for samples PFC5, PFC6 and PFC7, stage one seemed to span over a conversion range of 0 ≤ α ≤0.55, during the same temperature range. Additionally, PFC2 exhibited maximum char residue, indicating it may represent a more effective formulation. Furthermore, a detailed kinetic analysis would be processed in the future. [ABSTRACT FROM AUTHOR]

Groundwater quality was evaluated with a special emphasis on fluoride (F−) and iron (Fe) concentration, hydrogeochemical facies and suitability in terms of potability and irrigation (n = 32) was assessed in the mixed Ferricrete and Calcrete bearing region under 11 Gram-Panchayats in Gangarampur Block situated in South Dinajpur District of state of West Bengal in India in 2020. F− and Fe concentrations were beyond safe limits for drinking water (> 1.0 mg L−1) in 81.3% and 59.4% samples, respectively. Maximum recorded F− concentration was 4.6 mg L−1 while the lowest was 0.7 mg L−1 while Fe was 0.2–3.9 mg L−1. Nitrate (NO3−) concentration (13.4‒39.4 mg L−1) was found to be high vis a vis the reported levels of NO3 in some other regions of West Bengal but was always lower than the prescribed safe limit (45 mg L−1) for drinking water. Non-carcinogenic risk posed by F− exposure breached the Hazard Quotent limit in almost all samples for children (< 20 years) and adults (20–70 years) in the study area. A newly modified vulnerability assessment method was introduced and found 3 GPs amongst 11 GPs in the study area were highly vulnerable while 3 and 1 GPs respectively came under low and very low vulnerable areas. In the domain irrigation water quality, 62.5, 34.4, 25, 18.75 and samples were not found suitable for irrigating crops in terms of Permeability Index, Soluble Sodium Percentage, Residual Sodium Carbonate and Kelly's Index, respectively. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between groundwater quality and agricultural productivity across six experimental stations in Morocco: Doukkala, Bahira, Tassaout, Beni Amir, Beni Moussa and Tadla. To assess groundwater suitability for irrigation, a comprehensive suite of indices was employed, including the permeability index (PI), Kelly index (KI), sodium strength percentage (SSP), sodium adsorption ratio (SAR), residual sodium carbonate (RSBC), magnesium hazard (MH), Langelier saturation index (LSI), Ryznar stability index (RSI), aggression index (AI), Larson and Skold index (LS), and Puckorious saturation index (PSI). Results indicated significant variations among the stations. Doukkala showed moderate permeability and low salinity risk but high sodium levels (SSP 50.14, SAR 6.87). Bahira had similar trends with slightly higher PI and KI values. Tassaout demonstrated lower values across all indices, suggesting better groundwater quality. Beni Amir and Beni Moussa exhibited decreasing trends in indices, with Beni Moussa having the lowest values overall. Notably, Beni Amir had the most negative RSBC value, indicating a high sodium hazard and potential soil structure issues, while Tadla had the least negative RSBC value, indicating favorable conditions. Water in Beni Amir and Beni Moussa, with MH values of 56.37 and 56.84 respectively, was deemed unsuitable for irrigation, whereas Doukkala, Bahira, Tassaout, and Tadla, with MH values below 50, were considered suitable. The study concludes that groundwater quality varies significantly across regions, impacting agricultural productivity, with some regions posing higher risks due to sodium and magnesium hazards. [ABSTRACT FROM AUTHOR]

Environmental context: This manuscript focuses on the introduction of the conventional and modified Solvay processes. The Solvay process is used to produce sodium carbonate and sodium bicarbonate, while also providing brine management and CO2 capture. Optimal values must be used for reactant contents, temperature, salinity of the brine and stirring rate to enhance efficiency. The Solvay process is used to produce sodium carbonate and sodium bicarbonate. Simultaneous brine management and CO2 capture occur by the Solvay process. In this review, the Solvay process based on different solutions (i.e. NH3, KOH, CaO, Ca(OH)2 and alcohol amines) is reviewed. The most efficient processes considering CO2 uptake and Na+/Cl− removal are introduced. The Solvay process benefits from increasing NH3 content, salinity, stirring rate, decreasing temperature and using inert mixing particles in the reactor. Adding NH4HCO3, extra KOH in subsequent stages and brine pretreatment are recommended. The results show that a Ca(OH)2-based Solvay process, an NH3-based process running in contactor and reactor, and a 2-amino-2-methylpropanol-based Solvay process obtain the highest CO2 capture efficiencies of 99, 98 and 80% respectively. Environmental context. This manuscript focuses on the introduction of the conventional and modified Solvay processes. The Solvay process is used to produce sodium carbonate and sodium bicarbonate, while also providing brine management and CO2 capture. Optimal values must be used for reactant contents, temperature, salinity of the brine and stirring rate to enhance efficiency. (Image of the schematic diagram reproduced from with permission.) [ABSTRACT FROM AUTHOR]

Basic oxygen furnace slag (BOFS) is a high-volume waste resulting from the production of steel from pig iron. Due to its high free lime content, BOFS is difficult to recycle and/or include into conventional cement systems. Alkali-activation technology offers a pathway to transform industrial wastes such as BOFS into low-carbon cements. Alternative precursors for cement systems are needed as the reliance on commonly used materials like ground granulated blast furnace slag (GGBFS) is becoming unsustainable due to decreasing availability. This study investigates alkali-activated cements incorporating 20 and 30 wt.% of naturally weathered BOFS as a replacement for GGBFS, in both sodium silicate- and sodium carbonate-activated systems. A fraction of BOFS subject to mechanical activation is compared against the untreated BOFS in the 20 wt.% systems. It is observed that in naturally weathered BOFS, a significant portion of the free-lime is found to convert to portlandite, which accelerates alkali-activation kinetics. In sodium silicate-activated systems, the high pH of the activator results in incomplete reaction of the portlandite present in BOFS. The sodium carbonate-activated system shows near complete conversion of portlandite, causing an acceleration in the kinetics of reaction, setting, and hardening. These findings confirm the viability of sodium carbonate activated GGBFS-based systems with only a minor loss in strength properties. BOFS can be utilised as a valuable cement additive for the production of sustainable alkali-activated cements utilising sodium carbonate as a less carbon-intensive activator solution than the more commonly used sodium silicate. Mechanical activation of BOFS offers further optimisation potential for alkali-activation. [ABSTRACT FROM AUTHOR]

Residual arsenic in copper matte is a source of arsenic contamination in subsequent processes in the smelting section of copper pyrometallurgy. In order to solve the impact of arsenic in copper matte on the subsequent process of smelting, this study removes arsenic from copper matte by adding an arsenic removal agent to the molten copper matte. The results show that the most difficult arsenic phase in copper matte is the residual arsenic in copper-arsenic alloys, based on which sodium carbonate was selected as the arsenic removal agent. The arsenic content in the copper matte was reduced by 98% under the optimal experimental conditions of a reaction temperature of 1250 °C, 4% sodium carbonate addition, and a reaction time of 60 min. The experimental results of the reaction mechanism show that sodium carbonate plays two main roles in the process of removing the intractable residual arsenic in copper matte. One is that sodium carbonate has a low melting point, which enhances the fluidity of the reactants. The other is that it can provide oxygen to the reaction system and convert arsenic in the copper-arsenic alloy into gaseous arsenic and arsenate. This study can provide new ideas for controlling arsenic pollution in copper pyrometallurgy. [ABSTRACT FROM AUTHOR]

The current study was carried out to assess the suitability of laundry grey water (LGW) for reuse in irrigation so that it can help in the reduction of freshwater stress in irrigation sector. To address this objective, concentration of sodium (Na+), calcium (Ca2+), magnesium (Mg2+), carbonate (CO32−), bicarbonate (HCO3−), and phosphate (PO43−) were tested in fresh water (FW) collected before laundry washing and LGW generated after laundry washing from different households. The suitability of LGW for irrigation purpose was determined by using water quality indices such as Sodium adsorption ratio (SAR) and Residual Sodium Carbonate (RSC). The SAR values of FW at the rural and urban area sites varied from 0.84 to 1.10 and 0.82 to 4.30 respectively and remained in the excellent category for irrigation purpose. The SAR values of LGW at the rural and urban sites varied from 10.06 to 13.01 and 6.26 to 9.68, respectively. In contrast to the SAR values of the LGW at rural site, which remained under good quality category, SAR values remained under excellent category for irrigation purpose at urban sites. RSC values of FW and LGW were below 3.97 showing low or medium hazards associated with it for irrigation. [ABSTRACT FROM AUTHOR]

This is an article in the field of metallurgical engineering. Aiming at the limitation of low reactivity of barite and few chemical processing methods, a new soda ash conversion method is proposed. Firstly, the effect of barite reaction particle size, temperature, and sodium carbonate concentration on the production rate of barium carbonate by the hydrochloric acid hydrolysis method is explored. The results show that the sodium carbonate concentration has the greatest impact on the reaction conversion rate. At limited experimental conditions, when sodium carbonate is used when the concentration reaches 28.57%, the highest formation rate of barium carbonate reaches 90.05%. Secondly, in the subsequent reaction, ammonium chloride is selected to re-convert the barite conversion product to prepare ammonium carbonate. The barium carbonate produced by this method has a higher yield and purity. The new process breaks through the traditional misconception that barium sulfate does not react with soda ash. The process is simple and feasible, and ammonia and carbon dioxide can be recycled and reused, making the entire process a large cycle process, in line with the concept of green environmental protection, and recrystallization. The preparation of barium carbonate from stone provides a new production process.

In this work, copper carbonate/cobalt carbonate/manganese carbonate and copper oxide/cobalt manganese oxide/manganese oxide new nanocomposites were fabricated via precipitation of Cu(II)/Co(II)/Mn(II) solution using sodium carbonate and ignition of precipitate at 600°C for 3 h, respectively. Several instruments, including UV–Vis spectrophotometer, X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscope (TEM), nitrogen gas sorption analyser, and field emission scanning electron microscope (FE-SEM), were used to characterise the fabricated nanocomposites. Energy dispersive X-ray investigation confirmed that the composite produced owing to precipitation by sodium carbonate comprises carbon, oxygen, manganese, cobalt, and copper where the weight percentages are equal to 27.15, 52.49, 5.59, 5.75, and 9.02%, respectively. In addition, the composite produced owing to ignition at 600°C for 3 h comprises oxygen, manganese, cobalt, and copper where the weight percentages are equal to 8.62, 31.50, 38.58, and 21.30%, respectively. Transmission electron microscope examination confirmed that the composites produced owing to precipitation by sodium carbonate and ignition at 600°C for 3 h comprise polyhedral and spherical shapes with an average diameter of 36.85 and 22.34 nm, respectively. The BET surface area, average pore size, and total pore volume of the composite produced owing to precipitation by sodium carbonate are 29.8662 m2/g, 2.1634 nm, and 0.0323 cc/g, respectively. In addition, the BET surface area, average pore size, and total pore volume of the composite produced owing to ignition at 600°C for 3 h are 33.3714 m2/g, 5.2308 nm, and 0.0873 cc/g, respectively. 0.06 g of the fabricated nanocomposites degrade 100% of 60 mL of 15 mg/L of crystal violet dye solution within 20 min in the presence of hydrogen peroxide under UV irradiation. [ABSTRACT FROM AUTHOR]

Alkalization has been used in aquaculture to improve water quality and increase production. With its intensification, there is a demand for new alkalizing agents or the same agents but with different purities and particle sizes. Therefore, this study aimed to evaluate the effect of alkalizing on the cultivation of juvenile jundiá Rhamdia quelen in a recirculation system. The juveniles were cultured to four alkalization procedures: water without alkalization, water with sodium silicate, water with sodium bicarbonate, and water with calcium carbonate. At the end of the experiment, the biomass and biomass gain of the fish grown in sodium bicarbonate water were higher than those in the environment without alkalizing. There were no differences in other performance parameters such as weight, total length, head length, weight gain, length gain, survival, Fulton, or specific growth rate. The alkalinization doubled the alkalinity and increased the water pH, with the pH of calcium carbonate having the highest value and higher stability over time. The ammonia, nitrite, and nitrate concentrations demonstrated greater nitrification efficiency in waters that received alkalinization, mainly with calcium carbonate and sodium bicarbonate. Calcium carbonate water resulted in the highest hardness due to calcium, which provided the lowest phosphate concentration. The results, associated with the ease of obtaining and the price, suggest that sodium silicate has potential to alkalize and should be further studied. Sodium bicarbonate should be utilized as an alkalizing agent in the intensive cultivation of R. quelen juveniles. [ABSTRACT FROM AUTHOR]

A novel method for synthesizing dumbbell-shaped (Gd1−xTbx)2O(CO3)2·H2O (GOC:xTb3+) phosphors using sodium carbonate was investigated. An amount of 1 mmol of stable fluorescent powder can be widely prepared using 3–11 mmol of Na2CO3 at a pH value of 8.5–10.5 in the reaction solution. The optimal reaction conditions for the phosphors were determined to be 7 mmol for the amount of sodium carbonate and a pH of 9.5 in the solution. Mapping analysis of the elements confirmed uniform distribution of Gd3+ and Tb3+ elements in GOC:xTb3+. The analysis of fluorescence intensity shows that an optimal excitation wavelength of 273 nm is observed when the concentration of Tb3+ is between 0.005 and 0.3. The highest emission intensity was observed for GOC:0.05Tb3+ with a 57.5% maximum quantum efficiency. The chromaticity coordinates show that the color of GOC:Tb3+ is stable and suitable for fluorescence recognition. Latent fingerprint visualization reveals distinctive features like whorls, hooks, and bifurcations. Therefore, the sodium carbonate method offers an effective alternative to traditional urea chemical reaction conditions for preparing GOC:Tb3+. [ABSTRACT FROM AUTHOR]

Legumes, rich in protein, fiber, and micronutrients, are increasingly popular in pulse-based and gluten-free foods despite global consumption stagnating at 21 g/day due to taste, low protein digestibility, anti-nutrients, and long cooking times. Bean resistance to cooking causes textural defects like the hardshell and hard-to-cook phenomena. The pectin–cation–phytate hypothesis explains why soaking beans in sodium salts reduces cooking time by enhancing pectin solubility in water. Gradoli Purgatory beans (GPB), from Italy′s Latium region, were malted, reducing phytic acid by 32% and oligosaccharides by 63%. This study evaluated the hardness of cooked GPB seeds in various conditions, including decorticated or malted states, using a modified standard method. Cooking at 98 °C for 7–75 min on an induction hob with a water-to-seed ratio of 4 g/g was tested. Soaking was applied before cooking for conventional seeds only, followed by texture analysis. Conventional GPBs were adequately cooked if their cotyledons disintegrated upon pressing, requiring a force peak of 250 to 220 N and cooking times of 52 to 57 min. Malted, decorticated, and split GPBs cooked similarly to raw decorticated and split ones, with times of 32 and 25 min, respectively. Faster cooking was due to bean coat removal and splitting, not chemical changes. Sodium or potassium carbonate/bicarbonate at 1–2 g/L improved cooking efficiency, with 2 g/L of sodium carbonate reducing cooking time to 13 min. Higher concentrations caused non-uniform cooking. Cooking malted, decorticated, and split GPBs in sodium-carbonated water reduced greenhouse gas emissions from 561 to 368 g CO2e/kg, meeting the demand for eco-friendly and nutritionally enhanced plant protein sources. [ABSTRACT FROM AUTHOR]

High-iron Bayer red mud, containing over 30% of iron, is considered low-grade iron ore. Due to the global iron deficiency in recent decades, the effective utilization of the iron contained in high-iron red mud has received increasing attention. In this work, a technological scheme was developed for the extraction of iron into cast iron from red mud by smelting reduction, followed by rapid cooling to separate the metal from the slag. The influence of various experimental parameters, including temperature, basicity, and reduction time, on the recovery of iron from red mud was studied in detail. The results demonstrated that the separation of metal from slag was complete. The maximum extraction of iron into cast iron was obtained at a temperature of 1450 °C, with approximately 88.5% achieved in the absence of sodium carbonate and 91.5% with sodium carbonate. The optimal experimental result is of great importance for the large-scale and highly efficient recycling of red mud. [ABSTRACT FROM AUTHOR]

• In-situ BMED-CCUS realized high-value utilization of saline water and carbon as Na 2 CO 3. • Process parameters was optimized to improve carbon fixation performance and product quality. • This system outperforms the ex-situ method in process efficiency and integrity. In the context of carbon capture, utilization, and storage, the high-value utilization of carbon storage presents a significant challenge. To address this challenge, this study employed the bipolar membrane electrodialysis integrated with carbon utilization technology to prepare Na 2 CO 3 products using simulated seawater concentrate, achieving simultaneous saline wastewater utilization, carbon storage and high-value production of Na 2 CO 3. The effects of various factors, including concentration of simulated seawater concentrate, current density, CO 2 aeration rate, and circulating flow rate of alkali chamber, on the quality of Na 2 CO 3 product, carbon sequestration rate, and energy consumption were investigated. Under the optimal condition, the CO 3 2– concentration in the alkaline chamber reached a maximum of 0.817 mol/L with 98 mol% purity. The resulting carbon fixation rate was 70.50%, with energy consumption for carbon sequestration and product production of 5.7 kWhr/m3 CO 2 and 1237.8 kWhr/ton Na 2 CO 3 , respectively. This coupling design provides a triple-win outcome promoting waste reduction and efficient utilization of resources. [Display omitted] [ABSTRACT FROM AUTHOR]

Improvement of wear, corrosion, and heat-resistant properties of coatings to expand the operational capabilities of metals and alloys is an urgent problem for modern enterprises. Diffusion titanium, chromium, and aluminum-based coatings are widely used to solve this challenge. The article aims to obtain the corrosion-electrochemical properties and increase the microhardness of the obtained coatings compared with the initial Ti-6Al-4V alloy. For this purpose, corrosion resistance, massometric tests, and microstructural analysis were applied, considering various aggressive environments (acids, sodium carbonate, and hydrogen peroxide) at different concentrations, treatment temperatures, and saturation times. As a result, corrosion rates, polarization curves, and X-ray microstructures of the uncoated and coated Ti-6Al-4V titanium alloy samples were obtained. Histograms of corrosion inhibition ratio for the chromium–aluminum coatings in various environments were discussed. Overall, the microhardness of the obtained coatings was increased 2.3 times compared with the initial Ti-6Al-4V alloy. The corrosion-resistant chromaluminizing alloy in aqueous solutions of organic acids and hydrogen peroxide was recommended for practical application in conditions of exposure to titanium products. [ABSTRACT FROM AUTHOR]

The study object was slag from the Balkhash copper smelter, obtained by re-melting anode mud containing nonferrous metals. The process flow for processing these slags includes sintering with Na2SO4, Na2CO3, and coal, followed by soda-alkaline leaching of the sinter and extraction of metals from the solution into marketable products. Since sintering is the main operation providing high selectivity, the composition of the products of this process was studied. The main transformations during sintering were determined, and the optimal parameters were identified. The structures of slags and sintered materials obtained during the experiments were studied by electron-probe microanalysis. Sintering was performed at 600–800 °C. The best results for sulphidization of slag components were obtained at 800 °C; a further increase in temperature leads to the smelting of sinter particles and slows down sulphidization. The optimal quantities of additives, based on the weight of the slag, are Na2SO4—45%, Na2CO3—15%, and reducing agent—41%, with a sintering time of 2 h. These conditions enable the sulphidization of non-ferrous metals in the slag to the entire depth of the polymetallic globules. The distinct concentration of harmful impurities (Ni, As, and Sb) was observed in the fine structure of the polymetallic globules. [ABSTRACT FROM AUTHOR]

This work includes synthesis of the novel azo compound, which consists of diazotization of 3-nitroaniline followed by reaction with 4-hydroxybenzaldehyde in presence of sodium carbonate. The syanthesized azo compound was confirmed by characterization, using FT-IR, ¹HNMR, 13CNMR and GC-MS spectra. The azo compound was screened for solvatochromism, Halochromism using UV-Vis spectrophotometer, and found that the azo compound exhibited low solvatochromic and good Halochromic properties. While the dying study (Dye-doped Polymer Films), Poly ethylene was found the best polymer dyed by azo compound and showed good absorbance in the UV region. All fabrics were dyed with a yellow color except the cotton exhibiting a light brown color. [ABSTRACT FROM AUTHOR]

Recycling lithium (Li) from spent lithium-ion batteries (LIBs) due to the depletion of natural resources and potential toxicity is becoming a progressively favourable measure to realize green sustainability. Presently, the prevalent recycling technique relying on pyrometallurgy lacks the capability to extract lithium. Meanwhile, conventional hydrometallurgical processes frequently employ robust acidic solutions like sulfuric acid and precipitation agents such as sodium carbonate. Unfortunately, this approach tends to result in the extraction of lithium at the end of a lengthy process chain, leading to associated losses and creating challenges in managing complex waste. This study addresses a cost-effective and environmentally friendly early-stage lithium recovery from the thermally conditioned black mass. In this sense, a thermally conditioned black mass is subjected to the carbonization process in a water solution to transform the water-insoluble Li phase into soluble lithium bicarbonate (LiHCO3) and carbonate (Li2CO3) facilitating its selective separation from other elements. Response surface methodology (RSM)—a statistical tool integrated with central composite design (CCD) is employed to optimize the parameters for Li recovery. Temperature, solid–liquid (S/L) ratio, leaching time and CO2 flow rate are considered as variable factors in modelling the optimum recycling process. A quadratic regression model is developed for Li recovery and based on ANOVA analysis, (S/L) ratio, temperature and time are identified as statistically significant factors. Experimental results demonstrate a maximum leaching efficiency of lithium with optimized parameter set, achieving a recovery rate of 97.18% with a fit response of 93.54%. [ABSTRACT FROM AUTHOR]

Background: Tungiasis is a cutaneous parasitosis caused by the female flea Tunga penetrans. Two-component dimeticone (NYDA) is the only treatment for tungiasis recommended by the World Health Organization; however, this topical drug is not available in Kenya. In Western Kenya, sodium carbonate is commonly used in the treatment of tungiasis. This study evaluated the 7-day cure rates for tungiasis by comparing sodium carbonate and NYDA treatments in Homa Bay County, Kenya. Methodology/Principal findings: This was a randomized, observer-blinded, parallel-treatment cohort trial. Twenty-three eligible children with 126 flea infections were matched and randomized. All participants received both treatments, with one treatment on each foot. We recorded all health conditions/information, including inflammation scores and adverse events. Observations were performed on days 3, 5, and 7 using a digital microscope to confirm dead or live fleas based on the viability signs. Twenty-three children aged 3–13 years were analyzed. The proportion of dead fleas on day 7 was higher after NYDA treatment than after 5% sodium carbonate treatment (87% versus 64%, respectively, P = 0.01) NYDA. Median survival was 5 days for both treatments; NYDA had significantly higher trend of flea non-viability rate than 5% sodium carbonate (P<0.01). There were no significant differences in the inflammation score or pain/itchiness between the two treatments. On the last day, 14 children indicated their preference for NYDA in future treatment of tungiasis, whereas nine children preferred the 5% sodium carbonate solution. Conclusions/Significance: NYDA was significantly more effective than 5% sodium carbonate for tungiasis treatment. Both treatments were safe but the children preferred NYDA more. Future studies with more participants and an extended observation period are warranted to confirm our findings. The findings suggest that NYDA should be made more available in tungiasis endemic area. Trial registration: UMIN-CTR; UMIN 000044320 Author summary: Jigger infestation is caused by fleas. Most of the recommended treatments for jiggers are unaffordable; thus, local people experience difficulty with the usage. This study contribute to the understanding of the efficacy of two treatments against jigger infestation in the community: a local practice (soda ash solution) and a standard treatment (silicone oil). The study participants were 23 children aged 3–13 years with 126 fleas in Homa Bay County, Kenya. We administered the treatment only on day 1 and followed up on days 3, 5, and 7. At 7 days, the soda ash solution killed 64% of the fleas whereas the silicone oil killed 87% of the fleas. Thus, the safety of both treatments was confirmed. As this is the first step in investigating the efficacy and safety of the soda ash solution, we need to conduct further studies with more participants to compare both treatments. [ABSTRACT FROM AUTHOR]

This study investigated the sustainability aspect of the fly ash (FA)-based one-part geopolymers (OPGS) with various combinations and amount of alkali activators (AA). The three groups of OPG were: the M-OPG activated with solely sodium metasilicate-anhydrous (Na2SiO3), the MH-OPG with Na2SiO3 and sodium hydroxide (NaOH), and the MC-OPG with Na2SiO3 and sodium carbonate (Na2CO3). The compressive strength, embodied carbon, embodied carbon index, embodied energy and embodied energy index were identified. Test result shows that the M-OPG and MC-OPG with the AA/FA ratio of 0.20 attained 83 MPa and 75 MPa of compressive strengths, respectively. The MH-OPG with AA/FA ratio of 0.15 attained 72 MPa of compressive strength. The embodied carbon and embodied energy of the OPGs were mainly contributed by the Na2SiO3-anhydrous. The values were lowered when the Na2SiO3-anhydrous were partially substituted with NaOH or Na2CO3. Increasing the AA content increased the embodied carbon and energy. The embodied carbon index (3.80 kg CO2/m³/MPa) and embodied energy index (14.72 MJ/m³/MPa) of the MC-OPG with AA/FA ratio of 0.20 were the lowest. The outcome of this study supports the utilisation of Na2CO3 to partially substitute Na2SiO3 for the development of OPGs. [ABSTRACT FROM AUTHOR]

Bilayer hydrogels composed of poly(N-isopropylacrylamide) (PNIPAm) and poly(acrylic acid-co-acrylamide) (P(AAc-co-AAm)) are commonly utilized as anisotropic hydrogels with temperature and pH sensitivity. Nonetheless, PNIPAm is known to possess poor mechanical properties, a slow thermal response, and brittleness, which greatly restricts its application for temperature sensitivity. In order to overcome these limitations, a semi-interpenetrating network (semi-IPN) structure was created by combining PNIPAm with sodium alginate. This structure effectively addressed the issue of PNIPAm's brittleness, increased its tensile stress, and improved its tensile strain. Notably, a porogen such as sodium carbonate was incorporated to increase the porosity of the thermo-sensitive layer hydrogel, resulting in a faster thermal response rate. The bilayer hydrogel obtained can be used as a bidirectional hydrogel driver with both temperature and pH sensitivity. Mechanical manipulation through temperature changes or pH shifts can cause significant deformation in the hydrogel, making it a promising material for soft actuator applications. [ABSTRACT FROM AUTHOR]

The study presents results on the dependence of changes in the rheological characteristics (density and viscosity) of the products of phosphogypsum conversion with sodium carbonate on various factors, including temperature, concentration, sodium carbonate rate, stirring duration, and the temperature of the components mixture. Density was determined using the pycnometric method, and viscosity was measured with a VPJ-2 capillary viscometer. An increase in the concentration of sodium carbonate from 5 to 30%, maintaining it at a constant 105% of the stoichiometric rate, leads to an increase in the density and viscosity of the suspension from 1.0813 to 1.3922 g/cm3 and from 0.78 to 3.30 cP at 20°C, and from 1.0514 to 1.3091 g/cm3 and from 0.31 to 1.86 cP at 80°C, respectively. It was shown that increasing the stirring time from 15 to 120 minutes resulted in an average increase in the density and viscosity of the suspension by 1.02 to 1.08 times and 2.20 to 3.07 times, respectively, at 20°C and 80°C. The study revealed that the temperature of the mixture of phosphogypsum and sodium carbonate in the range of 20-90°C significantly increases the density and viscosity from 1.1922 to 1.2381 g/cm3 and from 1.35 to 2.75 cP, respectively, and from 1.1650 to 1.2033 g/cm3 and from 0.50 to 1.77 cP. With a 30-min conversion of phosphogypsum at varying rates (100–110%) and concentrations (10-30%) of sodium carbonate, the degree of phosphogypsum conversion increased from 84.09 to 97.07%. The optimal degree of phosphogypsum conversion (93.94%) was achieved at a sodium carbonate rate of 105% and a concentration of 20%. Experimental data on the rheological properties of the suspension obtained at various rates and concentrations of sodium carbonate showed the possibility of describing these properties using a linear and logarithmic function, with high correlation coefficient values (R2 = 0.95–0.99). The results provide an assessment of the feasibility of easily pumping the suspension in existing industrial equipment. [ABSTRACT FROM AUTHOR]

This research undertakes a comparative study between compacted phosphate-based (CPG) and alkaline-based (CAG) geopolymeric materials. The obtained materials underwent comprehensive evaluation through mechanical, physical, and chemical analyses. CPG exhibited superior mechanical strength, demonstrating an exponential growth with curing age in contrast to CAG. Both materials exhibited stable density over time, with CPG displaying a notably higher density attributed to its enhanced reactivity in an acidic medium. Dimensional variations revealed stable dimensions for CPG and subtle shrinkage for CAG, potentially associated with an observed efflorescence phenomenon. Visual assessments during water immersion highlighted the enhanced stability of CPG. Chemical analyses confirmed the persistence of mineralogical phases, such as quartz and illite, and the emergence of an amorphous geopolymeric network in both CPG and CAG samples. CPG materials featured aluminum phosphate phases, reinforcing structural integrity, while CAG materials exhibited sodium carbonate phases, introducing impurities, elucidating the superior performance of CPG over CAG. For the formation kinetics, CPG exhibited a faster reaction time than CAG, as evidenced by the evolution of pH, densification rate, and FTIR band over curing time. [ABSTRACT FROM AUTHOR]

• We study the chemistry of the core and ocean of Enceladus based on different core compositions. • We study the hydrothermal products from the ocean-core interaction in the context of the chemistry of the plume of Enceladus. • We evaluate the chemistry of the ocean based on its possible pH values and the saturation indices of mineral products. • We find that the actual composition of the core poses a somewhat wide range of possible compositional scenarios. Measurements made by the Cassini spacecraft instruments were able to reveal the composition of the geysers of the Saturn moon, Enceladus, among which salts (sodium chloride, sodium bicarbonate and/ or sodium carbonate) and traces of silica could be the result of hydrothermal processes from the interaction of an inner liquid ocean with the core of Enceladus. The chemistry of the ocean should be closely connected to the chemistry of the core. Even though. the actual composition of the core is unknown, Enceladus has been characterised as a moon with a silicate core and different authors have estimated the properties of the ocean. A core with a silicate composition alone, does not necessarily justify most of the observed species of the plume. Given the many uncertainties, in the current work, we study the possible chemistry of the core and the ocean in the context of a four-layered Enceladus (dry core, hydrated core, ocean and crust) with three different compositional scenarios for the core: primordial (represented by an ordinary chondrite), composite (represented by a carbonaceous chondrite with an igneous inclusion) and non primordial (epresented by a given peridotite). The scenarios comprise a set of minerals that interact with a primordial ocean (either pure or enriched water) at a given temperature and pressure, producing a series of secondary minerals and compounds, some of them, coincident with the chemical species observed in the geysers. Specifically, we make a chemical speciation for each proposed compositional scenario with the software PhreeqC, however our analysis is limited to the study of interactions that reach a given equilibrium. In particular, output values like the potential of hydrogen of the ocean or the saturation indices of mineral products may give us hints about the chemistry of the ocean and the core. We find that, based on the species observed in the plume, the actual composition of the core (and the ocean as well) poses a somewhat wide range of possible compositional scenarios and each of our proposed scenarios and their products justify, to some extent, the observations of the plume. [ABSTRACT FROM AUTHOR]

The direct electrochemical transformation of commercial LiFePO4 to NaxFePO4 olivine in a Na||LiFePO4 electrochemical cell with sodium electrolyte has been studied. Electrolytes containing 1 M of NaClO4 in ethylene carbonate (EC), dimethyl carbonate (DMC) and fluoroethylene carbonate (FEC) have been probed, and in the solvents with the ratio of EC:DMC:FEC=0.4:0.5:0.1 by volume, maximal values of the specific capacity (113 mAh g−1) with good cycling stability and maximal discharge currents are achieved upon sodiation. To determine the composition of the cathode material and utilization factor of LiFePO4, the dependence of open circuit voltage on specific capacity has been investigated. The general formula of the sodiation product can be written as Na0.88FePO4. Its theoretic specific capacity may be estimated as 135 mAh g−1. The composition of the products obtained is supported by XRD analysis, which suggests that in discharged cathodes, Coulombic influence of LiFePO4 crystallites on neighboring NaxFePO4 crystallites may enlarge the unit cell of the former and reduce its size of the latter. Probably, shrinkage in the presence of LiFePO4 stabilizes the olivine structure of NaxFePO4 and prevents its transformation from electrochemically active olivine to inactive maricite. [ABSTRACT FROM AUTHOR]

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

The study was conducted to determine the suitability of surface water from Oued El Gourzi for irrigation in the Fesdis area, Algeria, during irrigation season of July 2022. The suitability was assessed by analysing eight water samples collected from various sites along the Oued. A range of physicochemical parameters were examined, including EC, pH, Mg2+, Na+, Ca2+, K+, HCO3 - and Cl-, alongside other indices such as sodium absorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), permeability index (PI) and magnesium adsorption ratio (MAR) using standard procedures. The Richards classification shows that these waters are characterised by high salinity and low alkalinity hazard (C3-S1). According to the Wilcox classification, the majority of these waters are of doubtful quality, with only 25% exhibiting good quality for irrigation. Based on the RSC and MAR, all water samples are deemed safe and suitable for irrigation. However, PI values suggest that all sampling sites are of marginal quality for irrigation (class II). In terms of sodium and chloride concentration, all water samples were deemed unsuitable for irrigation. Based on these results, the waters pose risks for irrigation, particularly due to salinity, necessitating the implementation of special management practices and the selection of salt-tolerant crops. [ABSTRACT FROM AUTHOR]

In order to improve the fixational rate of reactive dyes, response surface methodology was used to optimize the dyeing process of cotbon fabric in systatin non-Rueous and less water medium. The interaction among sodium carbonate concentration, Fixation time and fixation temperature was studied, and the optimum process parameters were optimized^ sodium carbonate concentration 48 g/L, fixation time lOmin and fixation temperature 89 °C . According to the optimum process conditions, the predicted fixation rate is 75. 67%. The fixation rate calculated by experiment is 76. 73%, which is consistent with the predicted value [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco 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.)

In order to improve the utilization value of Perilla leaf polyphenol related food and food additives, and increase the edible added value of Perilla leaf, the polyphenol content of extracts from Perilla leaf was determined. The influence of Folin-Ciocalteu reagent dosage, sodium carbonate dosage, color developing temperature, color developing time and other factors on the determination of polyphenol content were investigated by single factor control variable method, and the determination conditions were optimized by response surface analysis. The experimental results showed that when the determination wavelength was 760 nm, the dosage of Folin-Ciocalteu reagent was 1.0 mL, the dosage of sodium carbonate reagent was 3.2 mL, the color development temperature was 30 °C, and the reaction time was 45 min, the optimal conditions for the determination of polyphenol content showed a good linear relationship with absorbance, and the regression equation was Y=0.0157X-0.0627, R2=0.9991. The stability, precision and reproducibility of the method met the requirements. The average recovery was 95.62% and the relative standard deviation (RSD) was 4.28%. The method was suitable for the determination of polyphenols in Perilla leaves, and the average content of polyphenols in Perilla leaves was 7.439 mg/g, RSD=4.34%. This study can provide data support for the development and researched of Perilla leaf polyphenols and food additives. [ABSTRACT FROM AUTHOR]

Enzyme‐catalyzed acylative kinetic resolution (KR) and dynamic kinetic resolution (DKR) of racemic primary and secondary alcohols have been widely reported to produce esters with high enantiomeric purity. In contrast, similar KRs of tertiary alcohols have been reported for only a limited range of substrates and require prolonged reaction times of several days. To gain deeper insight into the substrate scope and increase the process efficiency, we examined the reaction conditions using commercially available immobilized lipase A from Candida antarctica and found that the addition of the heterogeneous, inorganic base sodium carbonate significantly increased the reaction rate while maintaining high enantioselectivity. The use of vinyl hexanoate as the acyl donor provided esters that were stable during chromatography purification. The optimized reaction conditions were then successfully applied to a range of cyclic tertiary alcohols containing tetralin, dihydroindene, chromane, and thiochromane skeletons having, in part, a substituent on the aromatic ring. In this study on the structure–reactivity relationship of enzymatic KR‐type reactions, we achieved >30 % conversion for various tertiary alcohols in 24 h at 25 °C, producing optically active esters with 88–99 % ee. [ABSTRACT FROM AUTHOR]

The market for lithium-ion batteries (LiBs) is growing rapidly, the demand for lithium (Li) in the form of lithium carbonate (Li2CO3), which is the most common lithium mineralization form, is therefore also increasing significantly. Li is conventionally extracted as Li2CO3 using sodium carbonate (Na2CO3) to precipitate Li ions in an aqueous Li solution. However, Na2CO3 can also be replaced by CO2, which highlights the potential of using CO2 as a sustainable and economically viable alternative. This review focuses on technologies that utilize CO2 for Li2CO2 precipitation. First, the use of CO2 gas and Na2CO3 as carbonate sources are compared, and the need to consider important operating conditions with CO2 bubbling are then presented. Attempts made to increase the specific surface area of the reaction surface to enhance the utilization of CO2 gas and to produce micro-sized Li2CO3 powders are then reported, and the limitations associated with CO2 gas utilization are discussed. Although CO2 precipitation has limitations in terms of efficiency, scalability, and the fine-tuning of reaction conditions, this review shows that if CO2 precipitation technology is further developed, its use could be key to extracting and recycling next-generation Li. [ABSTRACT FROM AUTHOR]

The original non-conventional technique of preparing expanded bottle utilizing recycled bottle waste and a combination between glycerin in association with Na2SiO3 and Na2CO3, as liquid and respectively, solid expanding agents, was experimentally tested on an 800 W-electromagnetic wave oven and shown in this article. The work objective was obtaining a cellular glass with physio-mechanical and thermal features almost identical to those achieved by conventional techniques at industrial-scale. Thus, the heat conductivity was in the range of 0.060-0.072 W·m-1 ·K-1, while the compression resistance increased at 6.5-7.2 MPa. Also, the experimental results confirmed the remarkable power efficiency of the non-conventional process, the power use value being diminished to an extremely reduced measure (0.74-0.83 kWh*kg-1). In conclusion, the cellular product made by the unused technique worldwide proved to be suitable for application in special constructions. [ABSTRACT FROM AUTHOR]

Soil erosion poses a significant challenge to environmental management, threatening ecosystem health and sustainable development. Urgent action is required to implement effective erosion control measures within comprehensive environmental management strategies. This study investigates the effectiveness of sand crusts induced by Na2CO3-activated materials in mitigating soil erosion during various rainfall and windstorm events. The study evaluates the erodibility of Na2CO3-activated crusts under varying wind speeds (30, 60, 90, and 120 km/h) and rainfall intensities (30, 60, 90, and 120 mm/h) across 1 to 15 events. Surface strength is measured using penetrometer tests, and the microstructure of the formed crusts is examined through X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDS). The results underscore the effectiveness of Na2CO3-activated crusts in erosion control, with treated soil showing significantly reduced erosion compared to untreated soil under both wind and rainfall conditions. Penetrometer tests revealed a significant increase in surface strength, and microstructural analysis identified the formation of albite, anorthite, and brucite crystals, as well as various forms of calcite and portlandite phases in the treated soil. This study endorses Na2CO3-activated materials as a superior method for mitigating wind and rainfall erosion, highlighting their remarkable efficacy, eco-friendly properties, abundance of raw materials, straightforward implementation, and cost-effectiveness.