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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]

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]

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]

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]

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]

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]

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]

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]

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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]

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 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]

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]

At present, the National Metrology Institute of Japan provides six national primary pH buffers under the Japan Calibration Service System. Each batch of these buffers is certified by the primary pH method using a Harned cell. On the basis of these primary buffers, the designated laboratories supply the secondary and working pH standards using a high-precision pH meter. This paper provides an estimate of the batch-to-batch reproducibility of the primary pH standard production based on the history of the certification of primary carbonate buffers in NMIJ. This buffer, which was chosen as the subject of the study because of the relative difficulty of its measurements (and thus a greater dispersion of results), is nominally the 0.025 mol kg−1 equimolal solution of disodium carbonate and sodium hydrogen carbonate. As its pH value is significantly affected by the purity of the reagents used, the evaluation of their source materials is made by both pH measurements and acidimetric gravimetric back titrations. Considering the experimentally determined pH reproducibility of ca. 0.010, potential risks to the pH accuracy are discussed when using recipe-based carbonate pH standards. [ABSTRACT FROM AUTHOR]

The anthropogenic carbon dioxide (CO2) fixation and various engineering strategies are gaining very significant attention because of the expansion of the net‐zero carbon environment in the atmosphere. Herein, we designed a sodium aluminate@γ‐alumina (NaAlO2@γ‐Al2O3) catalyst by a simple and facile precipitation and impregnation tactics. A series of different weight percentage NaAlO2@γ‐Al2O3 materials were successfully synthesized and well characterized by using advanced analytical and spectroscopic techniques such as TGA, XRD, FE‐SEM, TEM/HR‐TEM, FT‐IR, Raman, TPD, and XPS analysis. The NaAlO2@γ‐Al2O3 catalyst was employed as a competent catalyst for the CO2 fixation under atmospheric pressure reaction conditions. The catalytic activity results evidently revealed that the cycloaddition reaction successfully achieved 94% styrene oxide conversion and 93% selectivity, along with an 87% yield of the styrene carbonate at 120 °C for 6 h. Furthermore, we comprehensively examined the effect of different reaction parameters such as the effect of sodium aluminate amount, co‐catalyst amount, temperature, and time for CO2 fixation reaction. Additionally, different terminal and internal epoxides were tested under optimized reaction conditions and achieved moderate to excellent yield of the desired cyclic carbonate products. Interestingly, a plausible reaction mechanism was proposed for the styrene carbonate synthesis using NaAlO2@γ‐Al2O3 catalyst surface with the support of characterization and experimental results. Remarkably, the NaAlO2@γ‐Al2O3 catalyst could be easily recoverable and successfully recyclable up to six consecutive cycles without declining its initial catalytic activity along with stable structural and physicochemical properties. [ABSTRACT FROM AUTHOR]

Maintaining soil fertility and structure in Libya requires attention to water quality and irrigation practices due to limited arable land. This study aims to assess groundwater quality in the BrackAshkada, Libya agricultural project based on physicochemical parameters such as electrical conductivity, total dissolved solids, total hardness and irrigation water quality index (IWQI), as well as some cations and anions, and irrigation indices such as sodium adsorption ratio (SAR), residual sodium carbonate, percentage sodium, permeability index, Kelly's index, potential salinity, total hardness (TH) and magnesium hazards percentage. The results indicated that IWQI is positively correlated with SAR and TH, and negatively correlated with the remaining indices. Based on the irrigation indices, the groundwater of the three wells was suitable for irrigation and can be classified as moderately water-restricted. The Piper diagram suggests that the mixed-type Ca-Mg-Cl-SO4 was dominant in the wells. The study concludes that groundwater is partially safe for agricultural use, but specific safety measures must be taken. These findings will assist farmers in enhancing soil management, crop cultivation and land sustainability. [ABSTRACT FROM AUTHOR]

The leaching solution from the direct reduction-sodium smelting process of ultra-poor vanadium-bearing titanomagnetite contained sodium, vanadium, and impurities. It was carbonated to ensure sodium recovery, and the recovery of vanadium proved challenging. This study proposed and optimized a novel process of extracting vanadium from this alkaline carbonated solution using the transformed organic phase of 20 vol% (0.44 mol/L) Aliquat 336, 8 vol% 2-octanol, and 72 vol% sulfonated kerosene. To achieve superior vanadium extraction, Aliquat 336 in the organic phase was transformed into carbonate type by successively washing with NaHCO3 and NaOH solutions. The single-stage extraction efficiency of vanadium exceeded 85% at a pH of 8.0‒9.0 and an organic-to-aqueous phase ratio of 1:1. The thermodynamics of the vanadium extraction process was examined, confirming that the extraction process is an exothermic reaction (ΔH0 = −9.56 kJ/mol). Furthermore, using a solution of 4 mol/L NH4Cl and 1 mol/L NH4OH with a pH of 8.8 as the effective stripping reagent to realize one-step stripping and precipitation of vanadium, the single-stage stripping efficiency of vanadium was 99.8%, and the precipitation efficiency was about 95%. Through this stripping-precipitation process, solid ammonium metavanadate with a purity of 98.14% was obtained in one step. The mechanisms of transformation, extraction, and stripping were studied via infrared spectra of the organic phases. [ABSTRACT FROM AUTHOR]

Rainfall does not always meet crop water demands in many areas, a problem that climate change is expected to exacerbate. Considering the high rate of seepage in earth ponds, there is an urgent need to improve irrigation effciency. This research evaluates an economic layer based on a simple technology to minimize seepage at the bottom. Therefore, it is recommended that sodium salts be used in combination with soil at the bottom of irrigation ponds. Three types of slightly plastic loamy soils were selected with clay contents of 20%, 15%, and 10%. The soil textures were determined first, followed by their chemical properties. Sodium carbonate was utilized at 0%, 2%, 4%, 6%, 8%, 10%, and 12% by soil weight. Finally, the falling head permeability test, Scanning Electron Microscope (SEM) analysis, pH, and compaction tests were conducted. Baed on the results, the maximum seepage reduction was achieved by using the silty-loamy soil sample with the lowest clay content compared to the other samples. The 10% sodium carbonate caused maximum reduction in permeability. For the pH and compaction test results, the addition of sodium carbonate decreased soil permeability and increased soil compaction. Overall, the results indicate that this pond sealer can effectively reduce seepage in farm irrigation ponds. [ABSTRACT FROM AUTHOR]

The present study explores a cost-effective method for using activated ground granulated blast furnace slag (GGBFS) and silica fume (SF) as cement substitutes. Instead of activating them with expensive alkali solutions, the present study employs industrial-grade powdered sodium aluminate (SA) and hydrated lime (HL) as activators, reducing expenses by about 94.5% compared to their corresponding analytical-grade counterparts. Herein, the exclusivity is depicted using less pure chemicals rather than relying on reagents with 99% purity. Two mixing techniques are compared: one involves directly introducing powdered SA and HL, while the other premixes SA with water before adding it to a dry powder mixture of GGBFS, SF, and HL. Microstructural analysis reveals that the initial strength results from various hydrate phases, including calcium–sodium–aluminate–silicate hydrate. The latter strength is attributed to the coexistence of calcium–silicate hydrate, calcium–aluminate–silicate hydrate, and sodium–aluminate–silicate hydrate, with contributions from calcite and hydrotalcite. The SF content significantly influenced the formation of these gel phases. Thermogravimetric analysis (TGA) reveals phase transitions and bound water related to hydration products. The optimal mix comprises 10% SF, 90% GGBFS, 9.26% HL, and 13.25% SA, with a water-to-solid ratio of 0.45. This approach yields a compressive strength of 35.1 MPa after 28 days and 41.33 MPa after 120 days, hence being suitable for structural construction. [ABSTRACT FROM AUTHOR]

Owing to their high discharge capacities, P2‐type transition metal layered oxides have attracted attention for use as positive electrode materials in Na‐ion batteries. However, owing to the Na‐deficient compositions of these oxides, additional Na+ must be supplied using a Na‐metal negative electrode to attain a high capacity in a half‐cell configuration. In this study, solid Na2CO3 powder was introduced into the P2−Na2/3Fe1/2Mn1/2O2 composite positive electrode as a sacrificial salt to compensate for the Na deficiency. Na+ was supplied through the electrochemical oxidative decomposition of Na2CO3 during the initial charging process; the decomposition mechanism responsible for this process was investigated in detail. Online electrochemical mass spectrometry confirmed that Na2CO3 was oxidatively decomposed in combination with the decomposition of the ethylene carbonate electrolyte. This reaction produced CO2, wherein the carbon source was derived from both Na2CO3 and the electrolyte. Consequently, Na+ supplementation improved the reversible capacity of the Na‐ion full cell. This study offers practical insights and a mechanistic understanding of the pre‐doping technique for Na‐free negative electrodes. This approach also compensates for the irreversible reductive capacity in a process that can be easily applied to practical sodium‐ and lithium‐ion batteries and capacitors. [ABSTRACT FROM AUTHOR]

'FL16045‐25' (Reg. no. CV‐1207, PI 704484), a soft red, facultative doubled‐haploid wheat (Triticum aestivum L.) cultivar, was developed and tested as FL16045DH‐25 by the University of Florida and released in October 2022. FL16045‐25 was derived from the cross MD07W478‐14‐5/GA06112‐13EE16. It is well adapted from Texas to Virginia and provides producers with an early‐season, facultative (Vrn‐A1_short), medium‐height, awned, semi‐dwarf (Rht2) cultivar that has high yield potential, good straw strength, good grain volume weight, and good end‐use quality. It expresses moderate‐to‐high levels of resistance to most diseases prevalent in the southern United States. Molecular marker analysis confirms the presence of Sbm1, Yr17/Lr37/Sr38, Lr18, Sr36/Pm6, Pm54, and Pm1a‐linked disease‐resistant genes. The yield average of FL16045‐25 from 41 environments during 2020–2022 ranged from 4211 to 5782 kg ha−1, which is competitive with check cultivars that are widely used in the southern part of the United States. The grain volume weight of FL16045‐25 ranged from 749 to 785 kg m−3 (32 environments), which was higher than most of the checks. FL16045‐25 has soft grain texture with softness equivalence varying from 51.3% to 59.3% and sodium carbonate solvent retention capacity (SRC) ranging from 66.8% to 68.5%. Flour yields on a Quadrumat Senior milling system varied from 68.7% to 69.5%. Flour protein content varied from 8.9% to 9.1%. Cookie spread diameter varied from 19.4 to 19.5 cm. The presence of TaSus2‐2B, Sucrose Synthase2 gene on 2B or 2G:2B, was confirmed by marker analysis. Core Ideas: FL16045‐25 is an early‐maturing, facultative, medium‐height wheat cultivar broadly adapted to the southern United States.FL16045‐25 has high yield potential and good straw strength, grain volume weight, and end‐use quality.FL16045‐25 demonstrated moderate‐to‐high levels of resistance to most diseases prevalent in the southern United States.Molecular marker analysis confirms the presence of Sbm1, Yr17/Lr37/Sr38, Lr18, Sr36/Pm6, Pm54, and Pm1a genes.It has above‐average resistance to Fusarium head blight disease. [ABSTRACT FROM AUTHOR]

In the present work, the development of geopolymeric materials with Na or K based on industrial kaolin samples, with variable kaolinite content and alkaline silicates, is studied. XRF, XRD, FTIR and SEM-EDS have been used as characterization techniques. Three ceramic kaolin samples, two from Algeria and one from Charente (France), have been considered. In particular, chemical and mineralogical characterization revealed elements distinct of Si and Al, and the content of pure kaolinite and secondary minerals. Metakaolinite was obtained by grinding and sieving raw kaolin at 80 μm and then by thermal activation at 750 °C for 1 h. This metakaolinite has been used as a base raw material to obtain geopolymers, using for this purpose different formulations of alkaline silicates with NaOH or KOH and variable Si/K molar ratios. The formation of geopolymeric materials by hydroxylation and polycondensation characterized with different Si/Al molar ratios, depending on the original metakaolinite content, has been demonstrated. Sodium carbonates have been detected by XRD and FTIR, and confirmed by SEM-EDS, in two of these geopolymer materials being products of NaOH carbonation. [ABSTRACT FROM AUTHOR]

We provide a synthesis of the history and the extent of human impact on the terrestrial ecosystems of the small islands and islets of the western Mediterranean. We focus on the exploitation of islands smaller than a few thousand hectares. The use of microinsular biotic resources (e.g., timber, soda ash, wild mammals) began as early as the Upper Palaeolithic, intensified during the Neolithic, and expanded during the Iron Age, peaking around the end of the nineteenth to the mid-twentieth century. As a consequence of long-lasting land exploitation, in many cases local terrestrial ecosystems were severely damaged and some of their living components disappeared. In other cases, even with uninterrupted human occupation over millennia, several insular resources have been sustainably managed. Although these small islands are currently under less pressure compared with neighbouring mainland coastlines, their protection or even the restoration is unquestionably necessary. [ABSTRACT FROM AUTHOR]

In this study, the fresh and hardened performance and durability of one-part ground granulated blast furnace slags (GGBFS) activated by solid CaO and Na2CO3 were discussed, and their hydration process and microstructure development were analyzed accordingly. Results showed that when the water-to-binder ratio was 0.32, the alkali-activated slag (AAS) paste exhibited lower flowability, higher yield stress and plastic viscosity. As the content of CaO and Na2CO3 increased, the yield stress, plastic viscosity, and compressive strength of AAS after hardening all increased. For the durability of the hardened sample, AAS with high content of activator have higher shrinkage strain and chloride ion flux. The microscopic analysis results indicated that AAS containing CaO and Na2CO3 exhibited more intense hydration heat release and rapid microstructure development in the early stage, thereby promoting the improvement of strength. The use of CaO and Na2CO3 to activate GGBFS has enormous application potential in solid waste utilization and carbon emission reduction, which can reasonably replace traditional Portland cement (PC) as a new generation of sustainable cementitious materials. [ABSTRACT FROM AUTHOR]

In this study, lithium was recovered from spent lithium-ion batteries through the crystallization of lithium carbonate. The influence of different process parameters on lithium carbonate precipitation was investigated. The results indicate that under the conditions of 90 °C and 400 rpm, a 2.0 mol/L sodium carbonate solution was added at a rate of 2.5 mL/min to a 2.5 mol/L lithium chloride solution, yielding lithium carbonate with a recovery rate of 85.72% and a purity of 98.19%. The stirring rate and LiCl solution concentration significantly impact the particle size of lithium carbonate aggregates. As the stirring rate increases from 200 to 800 rpm, the average particle size decreases from 168.694 μm to 115.702 μm. Conversely, an increase in the LiCl solution concentration reduces the lithium carbonate particle size, with an average particle size of only 97.535 μm being observed at a LiCl solution concentration of 2.5 mol/L. It was also observed that nickel and cobalt ions become incorporated into the crystal lattice of lithium carbonate, thereby affecting the growth and morphology of lithium carbonate. [ABSTRACT FROM AUTHOR]

Cotton stalks are residual biomass resulting from cotton bud harvesting, and they are composed primarily of lignocellulosic material. This material could be a source of functional polyphenols. To investigate this prospect, this study was undertaken with the view to examining whether an ethanol-based organosolv treatment could be suitable for producing extracts enriched in polyphenolic compounds. To this end, alkali catalysis was employed, and two catalysts, sodium hydroxide and sodium carbonate, were tested. The initial approach based on treatment severity showed that both catalysts may be equally effective in the recovery of polyphenols, yet in most cases studied, no clear trend between treatment severity and total polyphenol yield was recorded. The following study, based on response surface methodology, provided optimized conditions for both treatments, sodium hydroxide and sodium carbonate, where the recommended catalyst concentrations were 0.67 and 4%, respectively. Under a constant temperature of 90 °C and residence time of 300 min, the treatments with sodium hydroxide and sodium carbonate afforded total polyphenol yields of 18.4 ± 1 and 15.6 ± 1.9 mg CAE g−1 DM, respectively, which showed no significant statistical difference (p > 0.05). However, high-performance liquid chromatography analyses revealed that the sodium carbonate-catalyzed treatment produced extract particularly enriched in two hydroxycinnamate derivatives, ferulic and p-coumaric acid. This extract also exhibited increased antioxidant activity. The outcome of this study strongly suggests cotton stalks as a bioresource of functional substances, while mild alkali-catalyzed ethanol organosolv treatment appears to be a very promising technique for effectively delivering hydroxycinnamate-enriched extracts. [ABSTRACT FROM AUTHOR]

To investigate factors influencing the seed germination of Sichuan pepper (Zanthoxylum armatum DC.) and determine the optimal germination method, this study used an L16(43) orthogonal test. The effects of compound treatments, including 2.5% sodium carbonate degreasing time, indole acetic acid (IAA) concentration, and IAA soaking time on seed germination were examined. The results indicated that 2.5% sodium carbonate degreasing time was the primary factor affecting the germination rate and vigor index of the seeds. IAA concentration primarily affected the germination index and the duration of germination, whereas IAA soaking time primarily influenced the time lag of germination. In addition, the 2.5% sodium carbonate degreasing time had a significant effect on the germination rate; IAA concentration significantly impacted the germination index; and IAA soaking time had a significant effect on both the germination index and the time lag of germination. Through the analysis and evaluation of the membership function, the optimal treatment combinations for seed germination were determined to be a 24-hour degreasing time with 2.5% sodium carbonate, an IAA concentration of 200 mg·L−1, and an IAA soaking time of 12 hours. This study provides a valuable reference for the future propagation of Zanthoxylum armatum DC.

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.

Researchers have been chasing plastics that can automatically and fully degrade into valuable products under natural conditions. Here, we develop a series of water‐degradable polymers from the first reported fast and selective cationic copolymerization of formaldehyde (B) with cyclic anhydrides (A). In addition to readily accessible monomers, the method is performed at industrially relevant temperatures (~100 °C), takes tens or even minutes, and uses common acid as the catalyst. Interestingly, such polymers possess tunable AB/ABB‐type repeating units, which are considered to be thermodynamic and kinetic products, respectively, resulting in low carbon content ([O] : [C] up to 1 : 1). Notably, the polymers can completely degrade to valuable diacids within 150 days in water at ambient temperature owing to the incorporation of carboxyl terminals and acid‐responsive acetal units. By washing with aqueous sodium carbonate, the polymers are relatively stable over several months. [ABSTRACT FROM AUTHOR]

To develop a better process for synthesizing sodium percarbonate and getting separation of the sodium salt, the equilibrium of the ternary system Na2SO4–H2O2–H2O and Na2CO3–H2O2–H2O at 5 °C was determined using the isothermal method, and the appropriate synthesis conditions for sodium carbonate from a theoretical perspective was discussed. The Na2SO4–H2O2–H2O system phase diagram contains one co-saturated point of Na2SO4·0.5H2O2·H2O and Na2SO4·10H2O. The Na2CO3–H2O2–H2O system phase diagram contains three crystal zones: Na2CO3·10H2O crystallization field, 0Na2CO3·1.5H2O2·H2O crystallization field and Na2CO3·2H2O2·H2O crystallization field. According to the phase diagram, the suitable raw material ratio of sodium percarbonate synthesis was obtained, to get the maximum of product yield, the optimal mass ratio of Na2CO3 to 30% H2O2 is 0.609. [ABSTRACT FROM AUTHOR]

Diarylethene derivatives are one of the promising compounds for practical applications including optical memory, display, sensor, and photoactuator. In this work, we newly designed and synthesized an inverse type diarylethene derivative bearing sodium carbonate groups at the p‐position of the lateral phenyl ring and investigated the photochromic behavior in the presence and absence of cyclodextrins (CDs) (αCD, βCD, and γCD). Interestingly, only in the presence of βCD, the photocyclization reactivity decreased. From the results of job‐plots, NOESY spectra, and quantum chemical calculations, it was suggested that the distinctive interaction between the diarylethene and βCD leads to the restriction of molecular geometrical change, resulting in the suppression of the photocyclization reactivity. These results provide information on the rational designing of inverse type diarylethenes with advanced properties. [ABSTRACT FROM AUTHOR]

Corrosion-related damage incurs significant capital costs in many industries. In this study, an anti-corrosive pigment was synthesized by modifying calcium carbonate with sodium alginate (SA), and smart self-healing coatings were synthesized by reinforcing the anti-corrosive pigments into a polyolefin matrix. Structural changes during the synthesis of the anti-corrosive pigment were examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Moreover, thermal gravimetric analysis confirmed the loading of the corrosion inhibitor, and electrochemical impedance spectroscopic analysis revealed a stable impedance value, confirming the improved corrosion resistance of the modified polyolefin coatings. The incorporation of the anticorrosive pigment into a polyolefin matrix resulted in improved pore resistance properties and capacitive behavior, indicating a good barrier property of the modified coatings. The formation of a protective film on the steel substrate reflected the adsorption of the corrosion inhibitor (SA) on the steel substrate, which further contributed to enhancing the corrosion resistance of the modified coatings. Moreover, the formation of the protective film was also analyzed by profilometry and elemental mapping analysis. [ABSTRACT FROM AUTHOR]

Locally sourced agricultural residues are a promising feedstock for the production of reinforcement fibers for wastepaper-based packaging papers. An eco-friendly high yield process to generate fibers from wheat straw using high pressure steam and sodium carbonate is presented. The wheat straw was impregnated with up to 16% of sodium carbonate and steam treated for 10 min at temperatures from 148 °C to 203 °C. The pulps were characterized concerning their chemical composition and test sheets with 100% straw fibers and with 15% and 30% straw fibers blended with recycled pulp were prepared. Fiber yields ranged from 70% to 45%, wherein more severe treatment conditions contributed to increased paper strength but lower yields. At comparable fiber yields, treatments featuring a higher chemical input, coupled with lower treatment temperatures, resulted in improved paper strength. By blending recycled pulp with up to 30% of straw fibers with a beating degree of roughly 45 °SR, the burst, compression and tensile strength was enhanced by up to 66%, 74% and 59%, respectively. As the enhancement effect decreases with a high steam treatment intensity and a high proportion of wheat straw, a moderate treatment and limited use of wheat straw may be the best choice. [ABSTRACT FROM AUTHOR]

Analytical grade Sodium chloride (NaCl) is one type of salt with a purity of > 99.50 % NaCl content, including other impurities. In laboratories, salt is used as a reagent and a standard solution. This research carried out the salt production process through purification, acidification, neutralization, crystallization, and drying methods. Compared to existing technologies, the advantages of this technology are its simplicity and ability to produce accompanying products. In the first stage of the purification process, the precipitation of sulfate (SO4 2-) and magnesium (Mg2+) ions was examined. In this step, 20 % w/v barium chloride (BaCl2) ions using 20 % w/v sodium carbonate (Na2+) ions using 20 % w/v sodium carbonate (Na2CO3) solution, and the mixture was again separated by filtering after 12 hours. All stages of the purification process have shown that the ions concentration decreases by adding BaCl2, NaOH, and Na2CO3 solution. Furthermore, the acidification, neutralization, and crystallization processes can control pH and potassium (K+) content. The results demonstrated that the technology produced 30% analytical grade NaCl with purity > 99.50% and high brine solution as a by-product, which can be further processed for producing pharmaceutical and food-grade salts. [ABSTRACT FROM AUTHOR]

The hydration mechanism and strength development of alkaline salt-activated cementitious materials primarily rely on the alkaline activators and mineral admixtures employed. However, the impact of increased Mg2+, Al3+, and Si4+ resulting from the addition of MgO and steel slag (SS) on the hydration mechanism of these systems remains undetermined. This study delves into the hydration mechanism and mechanical properties of a Na2CO3-MgO-activated regenerated micropowder-slag-based cementitious material system. Mechanical properties were assessed by measuring dry shrinkage and compressive strength at various ages, up to 28 days. The reaction mechanism was scrutinized using X-ray diffraction and a thermogravimetric analysis. The main reaction products contributing to the strength development are C-S-H, C-(A)-S-H gel, and hydrotalcite. Other carbonate-containing phases make smaller contributions. The findings reveal that when SS usage is at 10%, it yields higher early strength compared to ordinary samples. Samples incorporating MgO and SS achieved strengths similar to or surpassing those of the control samples. A noteworthy observation is the synergistic excitation effect between sodium carbonate (NC) and MgO, leading to the generation of a significant amount of gelling substances. These substances fill the pores of the structure, resulting in the formation of a dense microstructure. Consequently, the enhanced interaction between NC and MgO contributes to the overall strength development of the cementitious material. [ABSTRACT FROM AUTHOR]

More than 60% of the world's sedimentary rocks are mudrocks (Potter et al., 1980; Schieber, 1998; Potter, 2003; the term mudrock is favored here over mudstone because the latter term was used to characterize a limestone texture; Dunham, 1962). From a palaeontological perspective these are, compared to sandstones and limestones, heavily undersampled. The main reason for this is that mudrocks decay in surface exposures to small chips, which develop with sun/heat and rain into an awkward pulp. The decay of the mudstone concomitantly destroys all macrofossils which are not durable. This comprises fossils with an aragonitic or delicate calcitic shell unless they are preserved as pyritic or internal calcitic molds or preserved within calcareous concretions. Therefore, most of the fossils are not recorded in surface exposures. In addition, sedimentologic investigations of mudrocks are hampered because (i) compaction makes sedimentary structures hardly recognizableand (ii) good thin sections of mudrocks are exceedingly difficult to manufacture. For micropalaeontological investigations, mudrocks rich in organic material are especially difficult to process. Standard treatments with boiling water, sodium carbonate solution, or peroxide H2O2 generally fail to dissolve much of the sediment so that the fine fraction (and in mudrocks we usually need the 63μm-fraction) largely consists of clay particle aggregates. Yet there are methods to dissolve these aggregates. Otherwise, picking the microfossils would become extremely laborious. In this paper, some guidelines for successful palaeontological work in mudrocks are outlined. These are based on the author's personal experience. Examples from Jurassic mudrocks of Switzerland/Europe show that such excavations can be very rewarding. [ABSTRACT FROM AUTHOR]