Search Results (474)

Designing ionic liquids (ILs) where a single functional group orchestrates a suite of enhanced properties remains a key challenge in materials science. Here, we introduce 1-butyl-3-methylimidazolium mandelate, [Bmim][Man], a novel IL where the hydroxyl group on the mandelate anion simultaneously enhances hydrogen bonding, thermal stability, antimicrobial activity, and extraction selectivity. The structure-property relationships of [Bmim][Man] were investigated through measurements of density, viscosity, and conductivity and were compared with analogous ILs. The presence of the hydroxyl group on the mandelate anion resulted in the highest density and viscosity among the series, attributed to strong hydrogen bonding and efficient ion packing. Notably, [Bmim][Man] exhibited a high molar conductivity that decouples from its high viscosity, suggesting an unusual degree of ion dissociation facilitated by the hydroxyl group. Thermogravimetric analysis revealed superior thermal stability. Furthermore, the investigated ionic liquid demonstrated a low critical aggregation concentration (CAC = 0.01982 mol·dm⁻³) in water, indicating a strong propensity for self-aggregation. [Bmim][Man] showed synergistic, enhanced antibacterial activity against E. coli and P. aeruginosa. Finally, the functional utility of this designed liquid was demonstrated in separation science, where [Bmim][Man]-based aqueous biphasic systems showed selective extraction capabilities for transition metals, a process driven by the same hydrogen-bonding and coordination interactions that define its bulk properties. These findings establish [Bmim][Man] as a promising multifunctional material where the mandelate anion concurrently dictates liquid microstructure, thermal resilience, antimicrobial performance, and application in extraction. Full article

Lithium (Li) is a critical metal element in geothermal systems, yet its enrichment mechanism in coastal geothermal waters remains poorly understood. This study focuses on the Xiamen coastal geothermal system, located in the South China granitic reservoir at the front of the Pacific subduction zone. Self-organizing map (SOM) classification, hydrogeochemical analysis, hydrogen–oxygen isotopic constraints, and a three end-member mass balance model were applied to identify the sources and enrichment mechanisms of Li. The geothermal waters are classified into two types: inland low-TDS (Cluster-1) and coastal high-TDS (Cluster-2). Isotopic data indicate a mixture of meteoric water and seawater as the recharge source. The model shows that seawater and groundwater mixing accounts for 2–45% of Li concentration, with over 55% derived from the rock end-member. The leaching of 0.002–0.187 kg of granite per liter of geothermal water explains the observed Li levels. Elevated temperature and low pH enhance Li⁺ release from silicate minerals, and reverse cation exchange further amplifies this process. A strong positive correlation between the CAI-II index and Li⁺ concentration reveals a synergistic effect of ion exchange in high-salinity environments. Overall, the results provide a quantitative framework for understanding Li enrichment and evaluating resource potential in coastal geothermal systems. Full article

There are 880 studies focused on trivalent chrome baths, and several studies suggest the formation of ${\left[Cr\left(III\right)L(H_{2}O{)}_5\right]}^{2+}$, where $L$ is an additive such as oxalate. The literature suggests that this compound decreases the energy needed in the electrodeposition process. We call this approach the inner-sphere complex hypothesis because these complexes are suggested, such as principal intermediate compounds. There are several disadvantages of this postulate, which are numbered in our study. This hypothesis was tested via Fourier transform infrared spectroscopy performed in attenuated total reflectance (ATR) mode. In addition, the potassium bis(oxalato) diaqua chromate (III) dihydrate ($K\left[Cr{\left(C_2{O}_4\right)}_2{\left(O{H}_2\right)}_2\right]·2H_{2}O$) compound was selected as a probe molecule because it contains bridging $C-O-Cr$ bonds, which are supposedly the largest number of bonds in the inner-sphere complexes in bath solutions. There is strong evidence of numerous bridging $C-O-Cr$ bonds in the solid sample; conversely, in solution, $Cr\left(III\right)$ prefers to form terminal bonds ($Cr-O$). These results suggest that the concentration of the inner-sphere complex is lower in solution. In solutions containing chromium (III) sulfate and oxalate anions, the concentrations of these complexes are much lower. Although some inner-sphere complexes are formed, their concentration does not seem to be relevant to the electrodeposition process. Otherwise, at high ionic strengths, the formation of ion pairs and hydrogen bonds between $Cr\left(III\right)$ and additives is probable. Our research highlights the importance of vibrational spectroscopy in resolving the mechanics of the trivalent chrome electrodeposition process. This is the first study reporting a band of $Cr-O$ bonds in trivalent chrome baths. Full article

The increasing contamination of neonicotinoid pesticides in the environment has become a growing concern, and biochar is considered a promising strategy for removing these pollutants. This study converted waste rice husks into biochar (RHB) via pyrolysis at 400–600 °C under anaerobic conditions, using dinotefuran (DIN) as a representative neonicotinoid. The physicochemical properties of RHB and its adsorption mechanisms for DIN were systematically investigated. Results showed that higher pyrolysis temperatures increased the specific surface area, microporosity, and aromaticity of biochar, while altering the distribution of surface functional groups. RHB prepared at 600 °C (RHB600) exhibited the highest adsorption capacity. The adsorption process followed the Sips isotherm and pseudo-second-order kinetic models, indicating a spontaneous and endothermic process involving heterogeneous physic–chemical adsorption. The primary mechanisms included pore filling, π–π interactions, and hydrogen bonding. The sequence of functional group response during DIN adsorption was C–O > C=C > C=O > –OH. Environmental factors such as solution pH and humic acid concentration significantly influenced adsorption, while phosphate ions caused strong competitive inhibition. An artificial neural network model accurately predicted adsorption under multiple interacting factors, and RHB600 demonstrated good regeneration after ethanol elution. This study confirms that RHB is an effective and practical adsorbent, providing a technical reference for agricultural waste valorization and pesticide-polluted water remediation. Full article

The fabrication of semiconductor devices with three-dimensional architectures imposes unprecedented demands on advanced plasma dry etching processes. These include the simultaneous requirements of high throughput, high material selectivity, and precise profile control. In conventional reactive ion etching (RIE), fluorocarbon plasma provides both accelerated ion species and reactive neutrals that etch the feature front, while the CF_x radicals promote polymerization that protects sidewalls and enhance selectivity to the amorphous carbon layer (ACL) mask. In this work, we present computational results on the role of CF₄ addition to hydrogen fluoride (HF) plasma for next-generation RIE, specifically cryogenic etching. Simulations were performed by varying the CF₄ concentration in the HF plasma to evaluate its influence on ion densities, neutral species concentration, and electron density. The results show that the densities of CF_x (x = 1–3) ions and radicals increase significantly with CF₄ addition (up to 20%), while the overall plasma density and the excited HF species remain nearly unchanged. The results of plasma density and atomic fluorine density are consistent with the experimental observations of the HF/CF₄ plasma using an absorption probe and the actimetry method. It was verified that the gas-phase reaction model proposed in this study can accurately reproduce the plasma characteristics of the HF/CF₄ system. The coupling of HF-based etchants with CF_x radicals enables polymerization that preserves SiO₂ etching throughput while significantly enhancing etch selectivity against the ACL mask from 1.86 to 5.07, with only a small fraction (~10%) of fluorocarbon gas added. The plasma simulation provides new insights into enhancing the etching performance of HF-based cryogenic plasma etching by controlling the CF₂ radicals and HF reactants through the addition of fluorocarbon gases. Full article

The purpose of this work was to develop and study catalytically active magnetic composites based on natural clays of Kazakhstan for their use in the process of catalytic wet peroxide oxidation (CWPO) of organic dyes. The synthesized materials, MnFe₂O₄/Shymkent and MnFe₂O₄/Ural, were obtained by intercalation of Fe²⁺, Fe³⁺, and Mn²⁺ ions into the interlayer spaces of natural aluminosilicates followed by heat treatment at 500 °C. The phase composition, morphology, and functional groups of the studied samples were characterized by the methods of elemental composition, X-Ray phase analysis, scanning electron microscopy, IR Fourier spectroscopy, and thermogravimetric analysis. The catalytic activity of the modified clays was evaluated in the decomposition reaction of methylene blue (MB) using hydrogen peroxide. To identify the influencing factors, adsorption experiments were conducted, including studying the effect of the adsorbent dose, the effect of pH on the degree of MB removal, and evaluating the activity of modified clays during the CWPO process under mild reaction conditions. The experiments were carried out at an initial dye concentration of C₀ = 50 mg/L, a catalyst dose of 0.25, 0.5, and 2.5 g/L, pH = 3 and 6, and a temperature of 50 °C. It was found that the degree of MB removal in adsorption experiments reaches 70% at a dose of 0.25 g/L and increases to 97.8–99% at 2.5 g/L. In terms of CWPO, with the addition of H₂O₂ complete degradation of MB was achieved within 120 min for MnFe₂O₄/Shymkent and 150 min for MnFe₂O₄/Ural. The high efficiency of the modified clays is explained by the formation of the MnFe₂O₄ ferritic spinel structure, an increase in porosity, specific surface area and hydrophilicity, as well as an improvement in the acid-base properties of the surface. The TGA results showed an increase in the thermal stability and uniformity of the composites. Thus, the developed magnetic composites can be considered as promising materials for the effective removal of organic pollutants from wastewater under mild CWPO conditions. Full article

Background/Objectives: Sleeve gastrectomy (SG) is the most commonly performed bariatric surgery worldwide. It results in significant weight loss and improves metabolic disorders such as hypertension. Weight loss is thought to be the main factor contributing to blood pressure (BP) reduction after SG. Small-intestinal hormones may also mediate the antihypertensive effects of SG. We aimed to investigate the mechanisms underlying the antihypertensive effects of SG through small-intestinal hormones independently of weight loss. Methods: This study involved male Sprague–Dawley rats that underwent a sham operation or SG, followed by a dietary intervention involving a standard diet, a high-fat and high-salt diet, or pair-feeding with SG. Results: Three weeks postoperatively, SG significantly reduced systolic blood pressure (SBP) and increased urinary sodium excretion. RNA sequencing of the small intestine revealed upregulation of the gene encoding prouroguanylin (proUGN). proUGN is a small-intestinal hormone that inhibits renal sodium reabsorption by converting sodium/hydrogen ion exchanger type 3 (NHE3) in the proximal tubules into the inactive phosphorylated form at Ser552 (pS552-NHE3). Furthermore, SG significantly increased proUGN levels in the ileum and plasma, as well as the levels of pS552-NHE3 in the renal cortex. The administration of exogenous uroguanylin, which is converted from proUGN, resulted in increased renal pS552-NHE3, increased urinary sodium excretion, and decreased SBP without body weight reduction. These effects were similar to those observed with SG. Conclusions: SG increases proUGN secretion from the small intestine, leading to increased blood concentration. This inhibits NHE3 activity in the proximal tubules, promotes natriuresis and reduces BP. Full article

The development of materials for the remediation and monitoring of water environments remains a significant challenge in the field of environment and materials science. In this study, a nickel-based coordination polymer, [Ni(L)(H₂O)₃]_n·nH₂O (1), was synthesized employing 4,4′-(1H,1′H-[2,2′-biimidazole]-1,1′-diyl)dibenzoic acid (H₂L). Single-crystal X-ray diffraction analysis showed that L²⁻ ligands connect Ni²⁺ ions into 1D Z-shaped chains via two coordination modes. The chains are further assembled into a 3D supramolecular structure through hydrogen bonding interactions. The photocatalytic test showed that complex 1 could effectively degrade the organic dye methylene blue (MB). Under the conditions of catalyst dosage 5 mg, MB initial concentration 20 ppm and pH 7, the degradation efficiency reached 87.7% within 180 min. In addition, complex 1 can be used for the electrochemical detection of norfloxacin (NOR) by differential pulse voltammetry (DPV), exhibiting a linear response in the concentration range of 2–197 μM and the detection limit (LOD) of 1.74 μM. These results demonstrate that complex 1 has bifunctional properties of photocatalytic degradation of organic dyes and electrochemical sensing of antibiotic NOR, making it a promising candidate material for the synergistic treatment of complex pollutants. Full article

Continental high water-cut reservoirs commonly exhibit strong heterogeneity, high viscosity, and insufficient reservoir drive, which has motivated the deployment of polymer-based composite chemical flooding, such as surfactant–polymer (SP) and alkali–surfactant–polymer (ASP) processes. However, conventional experimental techniques have limited ability to resolve intermolecular forces, and the coupled mechanism linking “formulation composition” to “microstructural evolution” remains insufficiently defined, constraining improvements in field performance. Here, scanning electron microscopy (SEM), backscattered electron (BSE) imaging, and molecular dynamics (MD) simulations are integrated to systematically investigate microstructural features of polymer composite systems and the governing mechanisms, including hydrogen bonding and electrostatic interactions. The results show that increasing the concentration of partially hydrolyzed polyacrylamide (HPAM) promotes hydrogen bond formation and the development of network structures; a moderate amount of surfactant strengthens interactions with polymer chains, whereas overdosing loosens the structure via electrostatic repulsion; the introduction of alkali reduces polymer connectivity, shifting the system toward an ion-dominated dispersed morphology. These insights provide a mechanistic basis for elucidating the behavior of polymer composite formulations, support enhanced chemical flooding performance, and ultimately advance the economic and efficient development of oil and gas resources. Full article

The development of durable and efficient catalysts capable of driving both hydrogen and oxygen evolution reactions is essential for advancing sustainable hydrogen production through overall water electrolysis. In this study, we developed a corrosion-mediated approach, where Ni ions originate from the self-corrosion of the nickel foam (NF) substrate, to construct Pt-modified NiFe layered double hydroxide (Pt-NiFeO_xH_y@NiFe-LDH) under ambient conditions. The obtained catalyst exhibits a hierarchical architecture with abundant defect sites, which favor the uniform distribution of Pt clusters and optimized electronic configuration. The Pt-NiFeO_xH_y@NiFe-LDH catalyst, constructed through the interaction between Pt sites and defective NiFe layered double hydroxide (NiFe-LDH), demonstrates remarkable hydrogen evolution reaction (HER) activity, delivering an overpotential as low as 29 mV at a current density of 10 mA·cm⁻² and exhibiting a small tafel slope of 34.23 mV·dec⁻¹ in 1 M KOH, together with excellent oxygen evolution reaction (OER) performance, requiring only 252 mV to reach 100 mA·cm⁻². Moreover, the catalyst demonstrates outstanding activity and durability in alkaline seawater, maintaining stable operation over long-term tests. The Pt-NiFeO_xH_y@NiFe-LDH electrode, when integrated into a two-electrode system, demonstrates operating voltages as low as 1.42 and 1.51 V for current densities of 10 and 100 mA·cm⁻², respectively, and retains outstanding stability under concentrated alkaline conditions (6 M KOH, 70 °C). Overall, this work establishes a scalable and economically viable pathway toward high-efficiency bifunctional electrocatalysts and deepens the understanding of Pt-LDH interfacial synergy in promoting water-splitting catalysis. Full article

The Ulan Buh Desert represents a quintessential desert ecosystem in the arid northwest of China. As the key factor to maintain the stability of ecosystem, the chemical characteristics of groundwater and its water relationship with vegetation need to be further studied. Through field sampling, hydrochemical analysis, hydrogen and oxygen isotope testing and the Bayesian mixing model (MixSIAR), this study systematically analyzed the chemical characteristics of groundwater, spatial distribution and vegetation water sources in the study area. The results show that the groundwater is predominantly of the Cl⁻–SO₄²⁻ type, with total dissolved solids (TDS) ranging from 0.34 to 9.56 g/L (mean: 2.03 g/L), indicating medium to high salinity and significant spatial heterogeneity. These characteristics are jointly controlled by rock weathering, evaporative concentration, and ion exchange. Soil water isotopes exhibited vertical differentiation: the surface layer (0–20 cm) was significantly affected by evaporative fractionation (δD: −72‰ to −45‰; δ¹⁸O: −9.3‰ to −6.2‰), while deep soil water (60–80 cm) showed isotopic enrichment (δD: −29‰ to −58‰; δ¹⁸O: −6.8‰ to 0.9‰), closely matching groundwater isotopic signatures. Vegetation water use strategies demonstrated depth stratification: shallow-rooted plants such as Reaumuria soongorica and Kalidium foliatum relied primarily on shallow soil water (0–20 cm, >30% contribution), whereas deep-rooted plants such as Nitraria tangutorum and Ammopiptanthus mongolicus predominantly extracted water from the 40–80 cm soil layer (>30% contribution), with no direct dependence on groundwater. Full article

In saline soil, legumes are restricted in their growth potential by osmotic stress, ion toxicity, and oxidative damage. We evaluated five halotolerant plant growth-promoting bacteria and selected Pseudomonas putida RT12 for its exceptional EPS production, tolerance to 600 mM NaCl, strong biofilm development, and plant growth-promoting traits (ACC-deaminase 2.86 µM·mg⁻¹; IAA 144 µM·mL⁻¹). RT12 was evaluated on two varieties of peas (peas2009 and 9800-10) with and without inoculation at 0, 75, and 150 mM NaCl concentrations. RT12 markedly protected growth under severe salinity: at 150 mM, shoot length rose to 23.13 cm (peas2009) and 17.44 cm (9800-10), in contrast to 11.18 cm and 12.32 cm in uninoculated specimens; root length and dry weight demonstrated comparable recovery (root length increased from 11.00 to 22.25 cm; dry weight of peas2009 from 0.15 to 0.17 and 0.41 to 0.71 g). RT12 sustained photosynthesis (total chlorophyll increased from 43.5 to 54.5), enhanced relative water content (to 94.1% and 97.2%), elevated osmolytes (total soluble proteins rose from 7.34 to 18.12 µg·g⁻¹ FW; total soluble sugars increased from 19.1 to 41.3 mg·g⁻¹ FW), and augmented antioxidant activities (catalase increased from 2.11 to 4.70; superoxide dismutase rose from 1.20 to 4.83; peroxidase increased from 0.08 to 0.18), while reducing malondialdehyde/hydrogen peroxide levels. RT12 was significant as it inhibited the accumulation of Na⁺ (from 23.95 to 16.32 mg·g⁻¹ DW), elevated K⁺ levels (from 17.76 to 29.12 mg·g⁻¹ DW), and restored the K⁺/Na⁺ ratio to normal (from 0.74 to 1.59) in inoculated plants compared to non-inoculated ones. A multivariate analysis linked growth protection to ionic homeostasis, osmotic control, and the detoxification of reactive oxygen species (ROS). RT12 is a promising bioinoculant for cultivating peas in saline-affected soils. Full article

Near-complete (>99%) dissolution of lithium and cobalt was achieved by the leaching of black mass from spent (end-of-life) lithium-ion batteries (LiBs) using 4 M H₂SO₄ or HCl at 60 °C. Raising the temperature to 90 °C did not increase the overall extraction of lithium or cobalt, but it increased the rate of extraction. At 60 °C, 2 M H₂SO₄ or 2 M HCl performed similarly to the 4 M H₂SO₄/HCl solution, although extractions were lower using 1 M H₂SO₄ or HCl (~95% and 98%, respectively). High extractions were also observed by leaching in low pulp density (15 g/L) at 60 °C with 2 M CH₂ClCOOH. Leaching was much slower with hydrogen peroxide reductant concentrations below 0.5 mol/L, with cobalt extractions of 90–95% after 3 h. Pulp densities of up to 250 g/L were tested when leaching with 4 M H₂SO₄ or HCl, with the stoichiometric limit estimated for each test based on the metal content of the black mass. Extractions were consistently high, above 95% for Li/Ni/Mn/Cu with a pulp density of 150 g/L, dropping sharply above this point because of insufficient remaining acid in the solution in the later stages of leaching. The final component of the test work used leaching parameters identified in the previous experiments as producing the largest extractions, and just sulphuric acid. A seven-stage semi-continuous sulphuric acid leach at 60 °C of black mass from LiBs that had undergone an oxidising roast (2h in a tube furnace at 500 °C under flowing air) to remove binder material resulted in high (93%) extraction of cobalt and near total (98–100%) extractions of lithium, nickel, manganese, and copper. Higher cobalt extraction (>98%) was expected, but a refractory spinel-type cobalt oxide, Co₃O₄, was generated during the oxidising roast as a result of inefficient aeration, which reduced the extraction efficiency. Full article

Background/Objectives: Tooth wear (TW) is a prevalent multifactorial condition resulting from chemical erosion and mechanical forces, yet the contributions of risk-group status and salivary factors remain insufficiently characterized. This study aimed to investigate the relationship between salivary characteristics and the severity of chemical and mechanical TW in at-risk groups, including gastroesophageal reflux disease (GERD), sleep bruxism (SB), eating disorders (EDs) and gambling disorder (GD). Methods: This cross-sectional observational study enrolled adults categorized into the four mutually exclusive at-risk groups and an age and sex-matched healthy control group. Demographic information, medical history, oral hygiene, diet, stress, and parafunctional habits were obtained through questionnaires. TW was assessed by a single examiner using TWES 2.0. Maximum bilateral force and salivary pH, flow and buffer capacity was measured. Correlations, multivariate linear regression, and mediation models were used to explore the relationships between the different variables and TW. Results: In total, 147 participants, divided into five groups (34 with GERD, 28 with SB 20 with GD, 20 with ED, and 45 controls) were included. The lowest resting salivary pH was observed in the GERD and ED groups (GERD: 6.63 ± 0.61; ED: 6.62 ± 0.52). The GERD group also exhibited the highest chemical (1.51 ± 0.58) and mechanical (1.08 ± 0.58) TW. Chemical and mechanical wear were strongly correlated, and mechanical wear increased with age. Risk-group status and salivary pH explained 47% of chemical wear, while age and bite force explained 54% of mechanical wear. Conclusions: Chemical TW was strongly linked to risk-group status—particularly GERD/ED—and low salivary pH, while mechanical TW related to age and bite force. Further longitudinal studies with larger samples, employing standardized methodologies and criteria are needed. Full article

We present an experimentally validated, engineering-oriented framework for the design and operation of pin-to-water (PTW) atmospheric discharges to produce hydrogen peroxide (H₂O₂) on demand. Motivated by industrial needs for safe, point-of-use oxidant supply, we combine time-resolved diagnostics (FTIR, OES), liquid-phase analysis (ion chromatography, pH, conductivity), and coupled plasma-chemistry/fluid simulations to link plasma state to aqueous H₂O₂ yield. Under the tested conditions (14.3 kHz, 0.2 kW; electrode to quartz wall distance 12–14 mm; coolant setpoints 0–40 °C), H₂O₂ concentration follows a reproducible non-monotonic trajectory: rapid accumulation during the early treatment (typical peak at ~15–25 min), followed by decline with continued operation. The decline coincides with a robust vibrational-temperature (T_vib) threshold near ~4900 K measured from N₂ emission, and with concurrent NO_X accumulation and bulk acidification. Global chemistry modeling and Fluent flow fields reproduce the observed trend and show that both vibrational excitation (kinetics) and convective transport (mass/heat transfer) determine the productive time window. Based on these results, we formulate practical design rules—electrode gap (power density), discharge current control, thermal/flow management, water quality, and OES-based T_vib monitoring with an automated stop rule—that maximize H₂O₂ yield while avoiding NO_X-dominated suppression. The study provides a clear path for transforming mechanistic plasma insights into deployable, industrial H₂O₂ generator designs. Full article