Hydrochloric Research Articles

Deviations from ideality in solutions of dicarboxylic acid salts modeled within a BiMSA theory for flexible chains.

The binding mean spherical approximation theory is used to describe the thermodynamic properties of dicarboxylic acid salts by adding a chain term in the free energy. The dianions in these solutions are modeled as flexible charged chains composed of two, three, or four spheres. Five aqueous solutions of such salts are studied in different concentration ranges: dipotassium oxalate, disodium malonate, disodium succinate, potassium tartrate, and sodium tartrate. A description of the experimental deviations from ideality (osmotic and activity coefficients) for these salts is obtained. The model is compared with a previous one that does not include a chain contribution. It is found that the model with a chain contribution provides a more physically sound framework.

Assessing the Photocatalytic Degradation of Penconazole on TiO2 in Aqueous Suspensions: Mechanistic and Ecotoxicity Studies in Aerated and Degassed Systems

Penconazole (C12H15Cl2N3) is widely used to prevent fungal infection of fruits. Since this toxic fungicide is recalcitrant to biological degradation, it has harmful impacts on aquatic ecosystems. TiO2-based heterogeneous photocatalysis proved to be an efficient method for its mineralization. To monitor the processes occurring under the influence of illumination, the light absorbance, the pH, and the TOC of the samples were measured. The concentration of the model compound and the degradation products were determined by HPLC and IC. Penconazole did not decompose under UV light (λmax = 371 nm) without a catalyst. In the presence of TiO2, mineralization took place. The initial degradation rate in air (7.7 × 10−4 mM s−1) was 5 times higher than under argon. The formation rate of hydrochloric acid (1.04 × 10−3 mM s−1) in the former case significantly contributed to the acidification of the liquid phase. NH4+ also formed, at the rate of 5.9 × 10−4 mM s−1, and very slightly transformed to NO3−. Due to the intermediates identified by HPLC-MS, hydroxylation, H abstraction, and Cl elimination are involved in the degradation mechanism, in which photogenerated HO● radicals, conduction-band electrons, and (under air) superoxide radical anions (O2●−) play considerable roles. The intermediates proved to be much less toxic than penconazole.

Efficacy of Biorational Insecticides and Entomopathogenic Fungi for Controlling Cassida vittata Vill. (Coleoptera: Chrysomelidae) in Sugar Beet Crops.

The sugar beet flea beetle, Cassida vittata Vill. (Coleoptera: Chrysomelidae), is a major pest in Morocco's sugar beet crops and is primarily controlled with chemical insecticides despite environmental concerns. Our aim was to assess the impact of three biorational insecticides (spinosad at 30-7.5cc/hL, mineral oil at 2000-250cc/hL, and potassium salts of fatty acids at 1500-375cc/hL) and two entomopathogenic fungi (Alternaria murispora and Alternaria destruens applied at 1.0 × 108, 5.0 × 107, and 2.5 × 107 conidia mL-1) both individually and in combination on C. vittata adults. All treatments were conducted at 25 ± 1°C, with mortality recorded over 10days. Conidial germination was highest for A. murispora with mineral oil (98.4%). Alternaria destruens showed consistently high germination across treatments. At 100% concentration, A. murispora + mineral oil and A. destruens + mineral oil treatments achieved 96.67 and 92.00% mortality, respectively. Median survival times (MST) for A. murispora were 6.0days at 100% concentration, increasing to 10.0days at lower concentrations, while A. destruens had a consistent 10.0days MST. LC50 for A. murispora was 1.3 × 107 conidia mL-1 alone, increasing to 2.2 × 107 with spinosad, but remained 1.7 × 107 with potassium salts of fatty acids. For A. destruens, LC50 was 4.2 × 107 conidia mL-1 alone, decreasing to 1.5 × 107 with mineral oil, and 3.1 × 107 with potassium salts of fatty acids. Combining A. murispora with mineral oil and potassium salts of fatty acids enhanced efficacy against C. vittata.

Influence of sand type on acid resistance and capillary absorption capacity

This study aims to investigate the effect of binary and ternary combinations of river sand (RS), crushed sand (CS) and dune sand (DS) on the physical and mechanical performance of concrete subjected to acidic curing environments. The RS was replaced by CS and DS in different mass proportions. The five concrete mixtures M21(RS), M04(0.6CS + 0.4DS), M10(0.2RS + 0.6CS + 0.2DS), M15(0.4RS + 0.6CS) and M16(0.6RS + 0.4DS) were prepared. The sorptivity was evaluated by measuring the sorptivity coefficient (S, cm*s-0.5) after 28 days of submersion in distilled water. Concrete specimens were submersed in distilled water, 5% sulfuric acid (H2SO4), and 5% hydrochloric acid (HCl) for up to 180 days in order to test their acid resistance. Visual inspection, changes in mass and changes in compressive strength were used to evaluate the specimens' resistance to acid attack. The results indicated that replacing RS with CS led to an increase in sorptivity, while replacing RS with DS resulted in a decrease. When both CS and DS were used in place of RS, acid resistance in 5% HCl solution decreased. In 5% H2SO4 solution, substituting RS with CS reduced mass loss, but replacing RS with both CS and DS weakened the concrete's compressive strength.

Corrosion inhibition effects of celery (Apium graveolens) seeds extract on carbon steel in acid medium

The present study highlights the inhibition performance of celery seeds (CS) extract on carbon steel immersed in 1M HCl, using electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization methods. This extract is selected due to biodegradable, renewable, and foremost aspect, is safe towards both the human being and environment. The studied inhibitor was easily extracted by using a simple aqueous extraction procedure. The experimental results show that the investigated inhibitor can effectively retard the corrosion process that occurs to carbon steel in hydrochloric acid solution. Electrochemical impedance spectroscopy (EIS) spectra showed that inhibition efficiency increases with the increasing of (CS) extract concentration. Among the studied inhibitor showed maximum inhibition efficiency of 96,86% at 250 ppm. Polarization curves indicate that (CS) extract acted as mixed type of inhibitors with a predominant effect on the anodic reactions. Basic calculations for the adsorption studies were also carried out. The adsorption of the extract onto carbon steel surface followed the Langmuir adsorption isotherm.

Characterizations of Pectin from Choerospondias axillaris Fruit Pulp: Comparison of Different Extraction Methods.

Generally, the extraction method has a great influence on the quality of pectin. However, there is little study on the effect of extraction method on the properties of Choerospondias axillaris fruit pulp pectin (CAPP). Accordingly, the physicochemical, structural, and functional properties of CAPP extracted by hot water (HWE), hydrochloric acid (HAE), ultrasound (UAE), and ultrahigh pressure (UPE) were investigated. Among these four CAPPs, UPE had the highest yield (15.79%) and GalA content (60.44%). UAE showed the most abundant side chains and RG-I region (55.12%). The lowest molecular weight (233.13 kDa) and yield (8.64%) were found in HAE. Though HWE exhibited better yield than HAE, its Mw was the highest. Different from physicochemical characteristics, the extraction method had a small effect on the structure of CAPP. The crystalline structure and functional group composition of different CAPPs were similar, while the surface structure of UAE and UPE had irregular circular holes in comparison with HWE and HAE. Furthermore, the extraction method also showed a great impact on the function. Compared with HWE and HAE, UAE and UPE presented better thermal stability and emulsifying properties. Meanwhile, HAE and UAE showed better antioxidant ability and prebiotic properties among these four CAPPs. The above results indicated that UAE showed better yield and functional properties. Hence, ultrasound extraction could be used as an effective method to extract CAPP.

Chloride Interferences in Wet Chemical Oxidation Measurements: Plausible Mechanisms and Implications.

Wet chemical oxidation (WCO) methods measure total organic carbon (TOC) in aqueous solutions through the formation and detection of carbon dioxide (CO2). Prior research documents chloride (Cl-) interference during WCO. However, the mechanism that determines WCO interference is not established. We investigate WCO and find that formic acid exhibits TOC recovery (89-108%) within measurement uncertainty in the presence of Cl-, while acetic acid recovery is substantially reduced (3-67%). We postulate that chlorine radical (•Cl) formation during WCO alters oxidation pathways for organic compounds with methyl groups to form stable halogenated organic species that are thus not detected as CO2, reducing observed TOC recovery. We develop a kinetic model of elementary step reactions that reproduces observed TOC recoveries at multiple organic (1 and 5 ppm of C) and Cl- (>0.01 M) concentrations for both acetic and formic acids. Independent experiments with pyruvic acid and different halogen salts are consistent with the proposed mechanism. Our findings provide a plausible mechanistic explanation for Cl- interference in WCO-derived TOC measurements of environmental samples for which halogenated salts are present. A plausible mechanism provides a more complete understanding of how and why the TOC is biased low in environmental aquatic samples from saline environments when WCO is employed.

Boosting Thermogalvanic Cell Performance through Synergistic Redox and Thermogalvanic Corrosion.

Thermogalvanic cells with organic redox couple (OTGCs) have received significant attention for low-grade heat harvesting due to their high thermopower, versatile molecular design, and tailorable physiochemical properties. However, their thermogalvanic conversion power output is largely hindered by slow kinetic rate, which limits practical applications. In this work, we demonstrate a high-performance liquid quinone/hydroquinone (Q/HQ) based OTGC by synergistic coupling redox reaction and thermogalvanic corrosion. By adding hydrochloric acid (HCl) into electrolyte solution, HCl not only boosts intrinsic redox kinetic rate of Q/HQ, but also induces rapid thermogalvanic corrosion of the copper electrode. Notably, these two processes reinforce each other kinetically. Consequently, the Q/HQ-based OTGC exhibits a rapid kinetic rate alongside an increased thermopower, leading to a significantly enhanced power output density. As a result, the Q/HQ-based OTGC achieves an enhanced effective electrical conductivity σeff of 4.22 S m-1 and a record high normalized power density Pmax (ΔT)-2 of 108.7 μW m-2 K-2. This strategy provides a feasible and effective method for development of high-performance OTGCs.

Thermodynamics of Micelle Formation of Selected Homologous 7-Alkyl Derivatives of Na-Cholate in Aqueous Solution: Steroid Skeleton and the Alkyl Chain Conformation.

Bile acid salts are steroid biosurfactants that build relatively small micelles compared to surfactants with an alkyl chain due to the rigid conformation of the steroid skeleton. In order to increase the capacity of micellar solubilization of the hydrophobic molecular guest, certain C7 alkyl derivatives were synthesized. Namely, introducing an alkyl group in the C7 position of the steroid skeleton results in a more effective increase in the micelle's hydrophobic domain (core) than the introduction in the C3 position. In comparison, fewer synthetic steps are required than if alkyl groups are introduced into the C12 position of cholic acid in the Grignard reaction. Here, the thermodynamic parameters of micellization (demicellization) of C7 alkyl (number of C atoms in the alkyl group: 2, 3, 4, and 8) derivatives of cholic acid anion in an aqueous solution without additives are examined (which have not yet been determined) in the temperature interval T (10-40) °C. The critical micellar concentration and the change in the standard molar enthalpy of demicellization (∆hdemic0) are determined by isothermal calorimetric titration (ICT). From the temperature dependence of ∆hdemic0, the change in the standard molar heat capacity of demicellization is obtained (∆Cdemic0), the value of which is proportional to the hydrophobic surface of the monomer, which in the micellar state is protected from hydrophobic hydration. The values of ∆Cdemic0 indicate that in the case of C7-alkyl derivatives of cholic acid anion with butyl and octyl chains, parts of the steroid skeleton and alkyl chain remain shielded from hydration after disintegration of the micelle. Conformational analysis can show that starting from the C7 butyl chain in the alkyl chain, sequences with gauche conformation are also possible without the formation of steric repulsive strain between the alkyl chain and the steroid skeleton so that the C7 alkyl chain takes an orientation above the convex surface of the steroid skeleton instead of an elongated conformation toward the aqueous solution. This is a significant observation, namely, if the micelle is used as a carrier of a hydrophobic drug and after the breakdown of the micelle in the biological system, the released drug has a lower tendency to associate with the monomer if its hydrophobic surface is smaller, i.e., the alkyl chain is oriented towards the angular methyl groups of the steroid skeleton (the ideal monomer increases the hydrophobic domain of the micelle, but in aqueous solution, it adopts a conformation with the as small hydrophobic surface as possible oriented towards the aqueous solution)-which then does not disturb the passage of the drug through the cell membrane.

A Fluorescent Covalent Organic Cage for Ultrafast Detection of Picric Acid and HCl Vapor Sensing.

Covalent organic cages (COCs) have recently gained massive attention owing to their solution processability and structural flexibility. Herein, we report an amine-linked fluorescent COC (COC2) synthesized by adopting dynamic covalent imine chemistry followed by imine bond reduction and characterized with different spectroscopic techniques. The COC2 was utilized for highly sensitive, selective, and ultrafast detection of picric acid at the nanomolar level. The fluorescence quenching efficiency of PA towards the COC2 is 98.6 %, with a detection limit of 2.7 nM. PA sensing with the COC2, coated on a TLC plate and paper strip, exhibited an outstanding fluorescence quenching property. Furthermore, the COC2 unveiled solid-state acidochromism upon exposure to HCl acid fumes and was transferred back to the original form on exposure to NH3 vapors.

Stepwise extraction of zinc, indium and lead from secondary zinc oxide dusts experimental study

Secondary zinc oxide dust is rich in high-grade metals such as Zn, In, Pb, and Ga, and in the face of the depletion of ore resources at home and abroad, it is of great significance to seek an efficient process to realize the full resource recovery of valuable metals in secondary zinc oxide dust. In this study, on the basis of the thermodynamic analysis of the wet treatment process, three wet treatment methods, namely “low acid leaching”, “high acid leaching” and “chlorination leaching”, were used to explore the suitable parameters for stepwise extraction of Zn, In and Pb metals. The results showed that the three wet treatment methods could effectively extract the corresponding main elements, and the optimal leaching rates of Zn, In and Pb were 73, 90 and 94%, respectively. Thermodynamic analysis shows that under ideal conditions, the “cascade separation” of some or all metals can be theoretically achieved by using a suitable leaching solvent for zinc oxide dust. The concentration of sulfuric acid, the ratio of liquid solid volume to mass and temperature had great effects on the leaching rate of Zn and In, and the leaching rate of Zn and In also increased with the increase of the values of the three experimental parameters, which was positively correlated. The leaching rate of Pb will increase with the increase of sulfuric acid concentration, but when the pH of the solution system is < 2, Pb will form PbSO4 precipitate, which inhibits the leaching ability of Pb. In the chlorinated leaching system with “ammonium chloride + hydrochloric acid” as the leaching solvent, the excess Cl− and Pb2+ fully coordinated to promote the efficient leaching of Pb metal, and the initial pH value of the solution had a great influence on the Leaching Rate of Pb. The multi-stage combined wet treatment process is an effective solution to realize the full quantitative recovery of valuable elements in Secondary zinc oxide dust, In this paper, the suitable process conditions for stepwise extraction of Zn, In and Pb metals were obtained through wet treatment experiments, and the cascade separation of metals in zinc oxide dust was preliminarily realized, which provided an important idea for the efficient utilization of metallurgical dust and sludge solid wastes, and at the same time provided theoretical support for the industrial practice of recycling valuable elements in metallurgical dust.

Lavandula angustifolia Extract as a Green Corrosion Inhibitor for Protection of Mild Steel in HCl Acid Solution

Lavandula angustifolia Extract as a Green Corrosion Inhibitor for Protection of Mild Steel in HCl Acid Solution

Lannea microcarpa Leaves Extract as Corrosion Inhibitor for Aluminium Metal in Acid Medium

Techniques for weight loss, electrochemistry, scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were used to investigate the inhibitory impact of Lannea microcarpa leaves extract. The weight loss data showed that the plant extract's ability to suppress corrosion increased with higher concentrations and decreased with higher temperatures and HCl acid concentrations. According to the electrochemical data, the plant extract uses a mixed type mechanism to limit both cathodic and anodic reaction rates. Calculated activation energies were found to be higher in inhibited systems than in uninhibited systems, indicating physisorption, while negative values of ∆G point to a process that is both possible and spontaneous. The inhibitory mechanism was demonstrated by FTIR spectra to be an adsorption process through the functional groups present in the phytochemicals of the plant extract onto the surface of Al metal. SEM surface morphology study demonstrated the protection that the extract provided on the metal surface. Compared to other isotherm models that were examined, the adsorption data were found to be more reliable and suited the Langmuir isotherm well.

Catalysts based on vanadium-containing heteropoly compounds: influence of the outer-sphere cation on physicochemical and catalytic properties of Si-W-V heteropolyacid

The effect of the introduction of catalytically active vanadium(V) atoms on the physicochemical properties of silicotungstic heteropolyacid has been studied. The insertion of vanadium(V) atoms into the framework of monovacant lacunar W-containing heteropolyanions in the form of a H6V10O28 solution prepared by an environmentally friendly peroxide method has been shown to ensure the formation of a mixed Si-W-V heteropolyanions while maintaining the integrity of the structure. It has been demonstrated that the partial replacement of protons with large cations, such as Cs+ and nBu4N+, leads to the precipitation of insoluble acid salts of the composition A4,5H0,5SiW11VO40, the properties of which vary significantly depending on the type of introduced counterion (A+). The textural characteristics of the synthesized salts have been compared, the TG/DTG/DSC profiles have been obtained, and a phase composition has been analyzed. Characterization of samples after hydrothermal treatment by IR, XRD, and ICP-AES methods has proved the high stability of the synthesized salts. The samples have demonstrated catalytic activity in the oxidation of 5-hydroxymethylfurfural in an aqueous medium, providing the formation of 2,5-diformylfuran with a yield of up to 89%, and the possibility of reusing.

Expression Variations of Chloride Ion Channel Related Genes During Diapause Termination in Silkworm, Bombyx mori.

Instant and refrigerated acid soaking are commonly used in cocoon production to prevent or break diapause, and provide developable silkworm eggs for sericulture, while their mechanisms have not been fully understood. This study aims to investigate the mechanisms by which hydrochloric acid (HCl) or dimethyl sulfoxide (DMSO) promotes embryonic development in silkworm Bombyx mori, focusing on the chloride ion (Cl-) related gene expression profiles. Our results revealed that the HCl treatment of up to 6 min enhanced hatchability in freshly picked and cold-stored eggs, whereas a slight decrease in hatchability was observed in those treated with DMSO for 40 min. The genes encoding chloride ion channel proteins were cloned and transcriptionally analyzed by quantitative real-time PCR in B. mori 932 strain. Bioinformatics analysis showed that BmCLIC, BmGluCl, and Bmγ-Cl mainly clustered with Lepidopteran insect homologs, while there existed a relatively low conservation from B. mori to mammals. We further explored the mRNA levels of BmCLIC, BmGluCl, and Bmγ-Cl in different egg processing conditions and embryonic developmental stages following HCl or DMSO treatments. Our results revealed that the mRNA expression profiles of BmCLIC, BmGluCl, and Bmγ-Cl increased in 20 h post-egg oviposition and refrigerated eggs after acid soaking. Moreover, the relative expression level of BmCLIC and BmGluCl gene was the highest on the first day, and maximum relative expression level of Bmγ-Cl gene presented on the second day in diapause eggs after treatment, and then it showed diversity. The expression profiles of the candidate genes seem like the same trend of changes during the development of eggs treated with instant acid soaking or DMSO treatment. In general, in the production practice of soaking silkworm eggs with HCl or DMSO, Cl- channel is likely to play an important subsidiary role to promot the relieving of diapause.

In silico design, synthesis and characterization of quercetin derivatives as anti-diabetic agents

Diabetes mellitus is a dominant metabolic condition noticeable by determined high blood sugar levels, stanching from either poor insulin production or insulin resistance. Managing diabetes often includes hindering enzymes, such as alpha-amylase and alpha-glucosidase to control blood glucose points after meals. Natural polyphenols, such as quercetin, have proved major enzyme inhibitory activity, leading to developing interest in reviewing quercetin derivatives as prospective antidiabetic agents. This research emphasizes on the design, synthesis, and assessment of quercetin ester derivatives for their antidiabetic activity by means of in silico docking studies. The key area is to investigate the binding affinity of these derivatives to indispensable enzymes involved in carbohydrate metabolism, while also assessing their drug-likeness and toxicity features. Quercetin ester derivatives, EQ1 and EQ3, were produced through esterification reactions. Quercetin was reacted with benzoic acid and gallic acid, in that order, in toluene, using hydrochloric acid as a catalyst under reflux settings. To calculate the binding affinities, in silico docking studies were supported with human pancreatic alpha-amylase (PDB ID: 2QV4) and acid alpha-glucosidase (PDB ID: 5NN8). Drug-likeness was explored according to Lipinski Rule of Five, and toxicity was projected by computational modeling procedures. Docking studies showed that EQ1 and EQ3 had concrete binding affinities for alpha-amylase and alpha-glucosidase, exceeding the standard drug acarbose. EQ1 attained the highest docking score, with essential interactions such as hydrogen bonding and pi-pi stacking. Drug-likeness evaluation revealed no major rule violations, indicating favorable oral bioavailability for both compounds. Furthermore, toxicity predictions confirmed that EQ1 and EQ3 are non-toxic, underscoring their potential safety. The synthesized quercetin derivatives, EQ1 and EQ3, exhibit considerable promise as antidiabetic agents by inhibiting key enzymes. Their strong binding affinities, favorable drug-likeness characteristics, and non-toxic profiles highlight their potential for further biological studies to validate their effectiveness and therapeutic value in diabetes management.. KEYWORDS :Alpha-amylase/glucosidase inhibition, Analytical evaluation, Drug development, In silico studies, Quercetin ester derivatives, Synthesis.

A Comparative Study of the Rheological Behavior of Solutions of the Chitin-Glucan Complex from the Fruit Bodies of Armillaria mellea in Acetic and Hydrochloric Acids

A Comparative Study of the Rheological Behavior of Solutions of the Chitin-Glucan Complex from the Fruit Bodies of Armillaria mellea in Acetic and Hydrochloric Acids

Biomimetic remineralization of eroded dentin by synergistic effect of calcium phosphate and plant-based biomodifying agents: An in vitro study

Context: Dentin, due to its organic content, exhibits a high susceptibility to dental erosion owing to its high permeability to intrinsic acids. A crucial challenge for successful remineralization of demineralized dentin is reestablishing a complete spatial relationship between the mineral and collagen. Aims: This study aimed to evaluate the synergistic effect of casein phosphopeptide amorphous calcium phosphate fluoride (CPP-ACPF) with plant-based dentin biomodifying agents: Grape seed extract (GSE), green tea extract (GTE), and cranberry extract (CE) on biomimetic remineralization of eroded dentin. Settings and Design: Dentin samples were prepared and subjected to surface microhardness (SMH) analysis at baseline followed by erosive challenge with hydrochloric acid (0.01M) and pH cycling with citric acid (0.05M) and artificial saliva. The samples in all the groups except the control were subjected to surface treatments: CPP-ACPF, GSE + CPP-ACPF, GTE + CPP-ACPF, and CE + CPP-ACPF. Subjects and Methods: Samples from all the groups were subjected to Vickers Hardness Tester for Post Treatment SMH analysis. Samples were qualitatively evaluated for changes in ultramorphological characteristics of dentin surface using scanning electron microscopy (SEM) and were quantitatively analyzed for changes in the calcium (Ca)/phosphorous (P) ratio using energy dispersive X-ray analysis (EDAX). Statistical Analysis Used: Data obtained were statistically analyzed using ANOVA, paired samples test, and Tukey HSD test. P value &lt; 0.05 was considered statistically significant. Results: The samples pretreated with GSE showed the highest mean SMH followed by GTE and CE. The difference in % change was significant when GSE was compared to GTE and CE (P = 0.001 and P = 0.000, respectively). SEM pictomicrographs of demineralized dentin samples revealed enlarged and exposed dentinal tubules, and most of these tubules were unobstructed with no obvious sediments. Samples treated with test agents demonstrated amorphous crystal-like deposits occluding the dentinal tubules with higher incidence observed in the groups treated with the combination of the agents. EDAX analysis revealed the highest mean wt% of Ca and P in groups pretreated with GSE followed by GTE and CE. GSE showed the highest mean Ca/P ratio followed by CE and GTE. Conclusions: The findings of this study demonstrated a synergistic effect when CPP-ACPF was used after pretreatment with plant-based dentin biomodifying agents in causing biomimetic remineralization of eroded dentin.

Investigating the environmental impacts of lithium-oxygen battery cathode production: A comprehensive assessment of the effects associated with oxygen cathode manufacturing

Lithium-oxygen batteries offer remarkably high energy density compared to current lithium-ion batteries. The key to their electrochemical performance lies in the processes occurring at the air cathode. However, the complexity of these reactions, coupled with the by-products generated during discharge, can make the reaction process slow or impede their efficiency. This study evaluates the environmental impact of high-efficiency lithium-oxygen batteries cathodes, including titanium oxide composites, graphene-based composites and activated carbon-based composites, through a life cycle assessment across 18 impact categories using a cradle-to-gate approach with a functional unit of 25 kWh. Results show that active material production was the largest contributor to environmental impact, particularly Global Warming Potential. Among the evaluated cathodes, reduced graphene oxide/α-mnaganese oxide/palladium (rGO/α-MnO2/Pd) demonstrated the highest environmental impact, with a global warming potential of 1130.71 kg carbon dioxide from active material production, due to its energy-intensive synthesis and the use of chemicals like sulfuric acid, sodium borohydride, hydrochloric acid, and hydrogen peroxide. Additionally, the rGO/α-MnO2/Pd cathode had the highest Human Toxicity Potential and Ozone Depletion Potential. Batteries with graphene-based cathodes achieved a specific capacity of 7500 mAh.g-1, underscoring their performance potential while highlighting the need for more sustainable cathode manufacturing methods. These findings emphasize the environmental considerations necessary for large-scale lithium-oxygen batteries implementation.

Precisely controlled electrostatically sprayed sodium alginate/carboxymethyl chitosan hydrogel microbeads as super-adsorbent for adsorption of cationic dye.

In this pioneering study, electrostatic spraying (ES) technology with high voltages is proposed to reduce the size of hydrogel microbeads further, aiming to enhance the adsorption rate of cationic methylene blue (MB) dye. The increased voltages, ranging from 0.0 to 13.0kV, further decreased the size of electrostatically sprayed hydrogel microbeads crosslinked by hydrogen bonds between sodium alginate (SA) and carboxymethyl chitosan (CMCS) in hydrochloric acid. The size of SA/CMCS hydrogel microbeads was successfully reduced from 2000±121μm (SC-2000) to 400±15μm (SC-400). Notably, SC-400 exhibits the highest maximum adsorption capacity (qm) and rate constant (k2) at 840.3mg/g and 0.0598g/mg/min, respectively, at pH9.0 and a temperature of 25°C in the absence of ionic compounds, which is three times higher than that of SC-2000, due to their high specific surface area and pore volume. Through a series of adsorption studies and characterization analyses, SA/CMCS hydrogel microbeads displayed heterogeneous adsorption behaviors towards MB dye through electrostatic interactions between the deprotonated carboxylic groups and cationic MB molecules, where MB adsorption efficiency could be significantly influenced by pH and ionic strength. These findings suggest that ES technology is effective in synthesizing smaller SA/CMCS hydrogel microbeads with enhanced MB removal rates and stable adsorption capacities and their applications could be further explored for removing other organic dyes and toxic metals in subsequent research studies.