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• Water probe can be applied to a wide range of pH for acidic and alkaline particles. • A standard spectral library was constructed that identifies ions in complex systems. • Successfully pH measurement for multicomponent particles. • Correlations between volatile acid evaporation and pH were established. The acidity of atmospheric aerosols influences fundamental physicochemical processes that affect climate and human health. We recently developed a novel and facile water-probe-based method for directly measuring of the pH for micrometer-size droplets, providing a promising technique to better understand aerosol acidity in the atmosphere. The complex chemical composition of fine particles in the ambient air, however, poses certain challenges to using a water-probe for pH measurement, including interference from interactions between compositions and the influence of similar compositions on water structure. To explore the universality of our method, it was employed to measure the pH of ammonium, nitrate, carbonate, sulfate, and chloride particles. The pH of particles covering a broad range (0–14) were accurately determined, thereby demonstrating that our method can be generally applied, even to alkaline particles. Furthermore, a standard spectral library was developed by integrating the standard spectra of common hydrated ions extracted through the water-probe. The library can be employed to identify particle composition and overcome the spectral overlap problem resulting from similar effects. Using the spectral library, all ions were identified and their concentrations were determined, in turn allowing successful pH measurement of multicomponent (ammonium-sulfate-nitrate-chloride) particles. Insights into the synergistic effect of Cl–, NO 3 –, and NH 4 + depletion obtained with our approach revealed the interplay between pH and volatile partitioning. Given the ubiquity of component partitioning and pH variation in particles, the water probe may provide a new perspective on the underlying mechanisms of aerosol aging and aerosol–cloud interaction. [Display omitted] [ABSTRACT FROM AUTHOR]

This work investigates the effects of irradiation on Ti 3 SiC 2 -containing interphase or coating in SiC f /SiC using a cooperative experiment involving H and He ions. SiC/TiC/Ti 3 SiC 2 /Ti 5 Si 3 C x and SiC/Ti 3 SiC 2 were irradiated at room temperature and then annealed at 320 °C for 24 h. Results showed the lattice swelling in all phases. With increasing irradiation dose, SiC and Ti 5 Si 3 C x underwent amorphization, while TiC and Ti 3 SiC 2 remained stable due to their ionic bonds. Annealing facilitated the migration of collision products and H, He ions to grain boundaries and phase interfaces, reducing lattice swelling rates of TiC and Ti 3 SiC 2. The SiC/TiC interface displayed ion cluster accumulation, impacting the interface bonding strength, while the Ti 3 SiC 2 /Ti 5 Si 3 C x interface exhibited the formation of cavities. Conversely, the TiC/Ti 3 SiC 2 and SiC/Ti 3 SiC 2 interfaces were stable. These findings indicate that interphase or coating containing Ti 3 SiC 2 monolithic or TiC/Ti 3 SiC 2 multilayered structures possess strong irradiation resistance. [ABSTRACT FROM AUTHOR]

In this work, a novel anti-reduction mechanism was put up by substituting (Mg 1/3 Ta 2/3)4+ complex ion for Ti4+ ion in Ba 4.2 Sm 9.2 Ti 18-x (Mg 1/3 Ta 2/3) x O 54 (0 ≤ x ≤ 0.1) ceramics. The influence of (Mg 1/3 Ta 2/3)4+ complex ion on the sintering behavior, crystal structure, anti-reduction mechanism and microwave dielectric properties of Ba 4.2 Sm 9.2 Ti 18-x (Mg 1/3 Ta 2/3) x O 54 ceramics was investigated. The results indicated that Ba 4.2 Sm 9.2 Ti 18-x (Mg 1/3 Ta 2/3) x O 54 ceramics maintained a typical single-phase tungsten bronze structure. After doping, the ceramic exhibited dense structure and typical columnar grains. Raman spectroscopy and XPS analysis confirmed the reduction of oxygen vacancies and obtained a 7.86 % decrease of Ti3+ ions. Due to the anti-reduction of Ti4+ ions, Ba 4.2 Sm 9.2 Ti 18-x (Mg 1/3 Ta 2/3) x O 54 ceramics possessed an improvement in microwave dielectric properties. In Ba 4.2 Sm 9.2 Ti 18-x (Mg 1/3 Ta 2/3) x O 54 (0 ≤ x ≤ 0.1) ceramics, the Ba 4.2 Sm 9.2 Ti 17·95 (Mg 1/3 Ta 2/3) 0.05 O 54 (x = 0.05) ceramic sintered at 1350 °C for 4 h showed the best integrated microwave dielectric properties with ε r = 79.62, Q f = 10,450 GHz and τ f = −10.66 ppm/°C. [ABSTRACT FROM AUTHOR]

In recent decades, high polarization and low residual polarization lead-free relaxor ferroelectric ceramics have attracted lots of focus due to their great potential in dielectric capacitors for energy storage. In this work, Na 0.35 Bi 0.35 Sr 0.3 Ti (1-x) (Al 0.5 Nb 0.5) x O 3 (x = 0.00, 0.01, 0.02, 0.03, 0.04, 0.05) lead-free ceramics have been fabricated by the traditional solid-stated reaction method. By doping (Al 0.5 Nb 0.5)4+ complex ions into 0.7Na 0.5 Bi 0.5 TiO 3 -0.3SrTiO 3 , pure perovskite phases and reduced grain sizes are obtained. Increasing the AN concentration not only moves the T s toward the lower temperature, but also keeps the permittivity at a high average value, which shows a good thermal stability of the dielectric properties (ε r 150°C ∼3903 ± 15% in the range of 42–232 °C). Furthermore, Na 0.35 Bi 0.35 Sr 0.3 Ti (1-x) (Al 0.5 Nb 0.5) x O 3 presents a reduced residual polarization due to the improved relaxor behavior, and achieves a moderate energy storage property at low electric field of 155 kV/cm (when x = 0.04, W rec is 1.85 J/cm3, and η is 89.0%). More importantly, the ceramic also possesses great frequency, temperature and cycle stability. Hence, the (Al 0.5 Nb 0.5)4+ modified 0.7Na 0.5 Bi 0.5 TiO 3 -0.3SrTiO 3 ceramics have exhibited a potential application in dielectric capacitors for energy storage. [ABSTRACT FROM AUTHOR]

The photolysis can separate the lithium and iron leached by oxalic acid and H 2 O 2 from spent lithium iron phosphate cathode. The process free the addition of precipitant and no hazardous waste is generated. [Display omitted] • Photolysis instead of additional precipitants for metal separation and recovery. • Rapid and selective leaching of active material elements from spent LFP cathode. • No wastewater or hazardous emissions generated from the process. Recovering valuable resources from spent cathodes while minimizing secondary waste generation is emerging as an important objective for the future recycling of spent lithium-ion batteries, including lithium iron phosphate (LFP) batteries. This study proposes the use of oxalic acid leaching followed by ferrioxalate photolysis to separate and recover cathode active material elements from spent LFP batteries. The cathode active material can be rapidly dissolved at room temperature using appropriate quantities of oxalic acid and hydrogen peroxide, as determined through thermodynamic calculations. The dissolved ferrioxalate complex ion (Fe(C 2 O 4) 3 3−) is selectively precipitated through subsequent photolysis at room temperature. Depending on the initial concentration, the decomposition ratio can exceed 95 % within 1–4 h. Molecular mechanism analysis reveals that the decomposition of the Fe(C 2 O 4) 3 3− complex ion into water-insoluble FeC 2 O 4 ·2H 2 O results in the precipitation of iron and the separation of metal elements. Lithium can be recovered as dihydrogen phosphates through filtration and water evaporation. No additional precipitant is needed and no other side products are generated during the process. Oxalic acid leaching followed by photolysis offers an environmentally friendly and efficient method for metal recovery from spent LFP cathodes. The photochemical process is a promising approach for reducing secondary waste generation in battery recycling. [ABSTRACT FROM AUTHOR]

Extensive efforts have been devoted to magneto-optical (MO) glass, owing to its remarkable potential in modern optics, encompassing diverse applications such as optical isolation, modulation, and sensing. Although the Tb ions doped glass has good MO properties, high concentrations of Tb ions tend to cluster, resulting in glass crystallization. To further improve the performance of MO glass, we must improve the solubility of Tb ions and inhibit the oxidation of paramagnetic Tb3+ to diamagnetic Tb4+ by adjusting the glass composition. In this work, we conducted a comparative study on GeO 2 -B 2 O 3 -X 2 O 3 glasses doped with Tb 2 O 3 (TGBX, where X represents Ga or La) to elucidate the effects of Ga 2 O 3 and La 2 O 3 on glass properties. Our findings reveal that TGBG glasses exhibit superior MO performance compared to TGBL glasses. Notably, the Verdet constant of TGBG glass with 45 mol.% Tb 2 O 3 at 650 nm reaches 105 rad/(T·m). Although TGBL glass exhibits a lower Verdet constant, its higher glass network connectivity and higher concentration of Tb3+ ions suggest its potential for preparing larger-sized glasses with an increased Tb3+ molar ratio. [ABSTRACT FROM AUTHOR]

Wettability is a crucial factor controlling fluid transport and distribution in reservoir rocks. A significant discrepancy of reported contact angles for air plasma cleaned calcite-water-gas systems are evident from the literature. This work focuses on finding possible explanations for these discrepancies by studying the effect of two surface cleaning methods on the surface chemistry, which was utilized by employing XPS and TOF-SIMS analysis. Observed chemical changes were then discussed in relation to wettability. The two methods are i) air plasma cleaning, and ii) argon cluster ion cleaning. Air plasma cleaning exhibits a degree of reactivity towards the surface. The two surface cleaning methods are very similar in regard to efficiency. Air plasma cleaning of calcite surfaces resulted in an accumulation of low levels of metal oxides/hydroxyls. It was found that both quartz and calcite remain intact after surface cleaning, that is, neither of the cleaning processes degrade the material. It is suggested that the discrepancies in reported contact angle values is a combined effect of several factors, such as different degrees of i) surface roughness, ii) unavoidable adventitiously adsorbed hydrocarbons on the sample surfaces, and iii) non-native bulk components such as metal oxide/hydroxyls and biomarker material. [Display omitted] • Contact angle measurements are discussed in terms of wettability, which is a crucial factor in reservoir rocks. • Air plasma and argon cluster cleaning both efficiently removes hydrocarbons from the calcite and quartz surfaces. • Air plasma introduces oxidative chemistry into the surface and causes accumulation of trace amount of metal oxides. • It was found that neither of the cleaning processes degrade quartz or calcite. [ABSTRACT FROM AUTHOR]

Fluoride molten salt (KAlF 4) can modify Y 2 O 3 to form YOF, but the reaction degree of this process is difficult to control and tends to form a large amount of yttrium fluoride (YF 3) with low-strength. The reaction degree of the modification process of fluoride molten salt with Y 2 O 3 can be suppressed by the synergistic effect of chlorides (KCl-CaCl 2), which is mainly determined by the diffusion of fluorine-containing complex ions (AlF 4 -) in the fluoride-chloride mixed molten salts (FCMMS). The low diffusion rate of AlF 4 - in FCMMS directly leads to the decrease of the fluorination reaction rate and delays or even prevents the deeper fluorination process. After the synergistic modulation of Y 2 O 3 by FCMMS, only YOF is formed, and the formation of YF 3 is completely avoided. The strategy and mechanism may be applied to the economical preparation of YOF protective layer or YOF powder on low-cost Y 2 O 3 template. [ABSTRACT FROM AUTHOR]

In this paper, a series of Li 2 Zn[Ti 1- x (Co 1/3 Nb 2/3) x ] 3 O 8 (0.0 ≤ x ≤ 0.4) ceramics were prepared via the conventional solid-state method. The influences of (Co 1/3 Nb 2/3)4+ complex ions on the phase composition, spectral characteristics, microstructure, and microwave dielectric properties of Li 2 Zn[Ti 1- x (Co 1/3 Nb 2/3) x ] 3 O 8 ceramics were studied systematically. XRD analysis accompanied with Rietveld refinements showed that pure Li 2 ZnTi 3 O 8 solid solution ceramics with the cubic spinel structure were obtained at x = 0.2–0.4. New Raman-active mode of about 858 cm−1 should be attributed to the vibrations of NbO 6 due to the high bond energy of Nb–O bonds, exerting a certain impact on the structure and performance of Li 2 Zn[Ti 1- x (Co 1/3 Nb 2/3) x ] 3 O 8 ceramics. XPS results indicated that Nb5+ ion donor suppressed the deoxidation process and therefore resulted in the disappearance of Ti3+ ion and oxygen vacancy. The downward trend variation in the ε r value with the increase of (Co 1/3 Nb 2/3)4+ content could be explained by the presence of "compressed" cations and "rattling" cations effect. In addition, the Q × f of the current ceramics was closely dependent on relative density, grain size, FWHM, and oxygen vacancy. Good combined microwave dielectric properties of ε r = 24.5, Q × f = 91,250 GHz, and τ f = −16.8 ppm/°C were achieved for the Li 2 Zn[Ti 0.8 (Co 1/3 Nb 2/3) 0.2 ] 3 O 8 ceramic sintered at 1120 °C. High quality factor gives evidence that the Li 2 Zn[Ti 0.8 (Co 1/3 Nb 2/3) 0.2 ] 3 O 8 ceramic is an appealing candidate for highly selective microwave devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Thermosensitivestar-shapedpoly- N -acyl-1,3-propylenimines with a macrocyclic trianglamine core were synthesized using a 'grafting-on' approach involving polymerization of 2-alkyl-5,6-dihydro-4 H -oxazines at free trianglamine. The resulting polymers form complexes with europium ions and curcumin and can be used in the creation of delivery systems for drugs as well as contrast agents for NMR tomography. [ABSTRACT FROM AUTHOR]

After a series of earthquakes, the Reykjanes peninsula in Iceland faced a volcanic eruption for the first time in 800 years. This volcanism of the 2021 Fagradalsfjall started on March 19, 2021, and lasted until September 18, 2021. In this study, the vestiges of the mutual interplay of Earth's different geophysical shells due to the local lithospheric changes around the Fagradalsfjall were extensively investigated with the help of satellite-based remotely sensed datasets. Firstly, the regional surface deformations caused by the pre-eruption seismic activity are determined using interferometric image pairs, and horizontal and vertical displacement rates are analyzed. Secondly, the satellite observations revealed that the land surface temperature of the entire area increased to a maximum of 40 °C during the maximum phase of lava discharge by the end of May 2021. Moreover, we observed that the surface mass concentrations of SO 2 and CO trace gases started to ascend in parallel with the lava discharge after the initial eruption, where their concentrations were doubled in April before reaching their maximum phases (three to four times more than the initial eruption) in May 2021. The cumulative concentrations of the trace gases in the atmosphere emitted from the Fagradalsfjall volcano pushed the regional atmospheric balance into a non-equilibrium state by creating air ionization through various chemical reactions with other atmospheric gases. These ion clusters underwent an ion hydration process that changed the electric conductivity of the atmospheric boundary layer, which covers the first two kilometers of the atmosphere. Finally, our observations showed a sharp decrease in the atmospheric relative humidity that led to an increase in the atmospheric air temperature due to this ion hydration process. The large ion clusters in the atmospheric boundary layer produced a vertical electric field that penetrated over the affected region and brought long-term changes in the ionosphere layer. This unique phenomenon of the simultaneous interaction of different geophysical layers was specifically observed during the maximum phase of the lava discharge and increased ion concentrations in the atmosphere. The used data sets cover the first three months of the volcanism, and this interval seemed to be sufficient to reveal the atmospheric traces. Our comprehensive study provides an important contribution to the theory of the coupling of volcanism and the Earth's atmospheric dynamics. [ABSTRACT FROM AUTHOR]

The healing process of infected wounds was limited by bacterial infection, excessive reactive oxygen species (ROS) accumulation, and tissue hypoxia. In order to alleviate the above situations, herein, a copper-rich multifunctional ultra-small Prussian blue nanozymes (HPP@Cu NZs) was constructed for infected wound synergistic treatment. Firstly, hyaluronic acid was modified by branched polyethyleneimine which could form a complex with copper ions, to construct copper-rich Prussian blue nanozymes. Secondly, the HPP@Cu NZs have a uniform ultra-small nano size and excellent photothermal response performance, exhibition of multifunctional enzymatic activity and anti-inflammatory properties. Finally, the slow release of copper ions in the HPP@Cu NZs could effectively promote the formation of new blood vessels, thus giving it multifunctional properties. In vitro and in vivo experiments showed that it not only could effectively inhibit and kill bacteria under 808 nm near-infrared laser but also could remove excessive ROS, regulate oxygen levels, and anti-inflammation. More importantly, the release of copper ions could synergistically promote the healing of infected wounds as well as good biocompatibility. Overall, our studies provide a multifunctional strategy for infected wounds with synergistic treatment based on carrier construction. [ABSTRACT FROM AUTHOR]

H 2 O:C 2 H 6 ice mixture, in a proportion of approximately 1:10 and at 60 K in average, is irradiated by energetic multicharged ions (≈ 65 MeV 252Cf fission fragments). The sputtered positive and negative secondary ions are analyzed by time-of-flight plasma desorption mass spectrometry (PDMS-TOF). Several ionic species are identified, indicating strong surface fragmentation and clusterization. The bombardment induces the formation of the ion cluster series: (CH 2) n X, where X = CH 3 + , C 2 H 6 + or CH + , and the carbon cluster series (C) n X, where X = CH 3 + or CH −. It is found that, in general, the yield distributions exhibit exponential decays, Y = Y 0 F e x p (− k F n) + Y 0 S e x p (− k S n) , where k F =1.11 u−1 and k S =0.11 u−1. Such finding may be useful to understand the processes by which, in cosmic space, ionized molecular species of hydrocarbons are delivery to the gas phase. [ABSTRACT FROM AUTHOR]

Anion exchange membranes (AEMs) with high OH- conductivity, good alkaline stability, and dimensional stability are still challenges for AEM fuel cells to be used in practice. In this study, high-performance cross-linked AEMs are developed. To construct the hydrophilic ionic channels, a series of polysulfone-based cross-linked AEMs were prepared utilizing the DABDA cation and two distinct cross-linkers (one with ether and one without ether). The cross-linking process enhanced aggregation of ion clusters, which resulted in the formation of ion-conductive channels and phase-separated hydrophilic/hydrophobic morphology, as well as enhancing the dimensional stability of the AEMs. The produced AEMs demonstrated good conductivity relative to their swelling ratio at 70 °C, and high conductivity in the range of 19.6–46.7 mS/cm between 25 and 70 °C. Additionally, the cross-linked AEMs revealed enhanced alkaline, mechanical and thermal stability. This work presents a promising strategy for developing high-efficiency AEMs for fuel cells. [Display omitted] [ABSTRACT FROM AUTHOR]

Two triperiodic frameworks are formed when 2,5-thiophenedicarboxylate complexes the uranyl ion in the presence of N,N -dimethylacetamide or triphenylphosphine oxide as unidentate coligands. Both assemblies display channels accommodating the latter coligands. [Display omitted] 2,5-Thiophenedicarboxylic acid (H 2 tdc) has been reacted with uranyl nitrate hexahydrate under solvo-hydrothermal conditions with N,N -dimethylacetamide (dma) as an organic cosolvent, giving the complex [UO 2 (tdc)(dma)] (1), isomorphous to the previously reported [UO 2 (tdc)(nmp)] (nmp = N -methyl-2-pyrrolidone). With tdc2− adopting the bis(μ 2 -κ1 O :κ1 O')-bridging coordination mode, complex 1 crystallizes as a triperiodic framework with the point symbol {42.84}. With acetonitrile as an organic cosolvent and in the presence of [Ni(PPh 3) 2 Br 2 ], triphenylphosphine oxide is formed in situ and it binds to uranyl to give [UO 2 (tdc)(OPPh 3)] (2). Complex 2 is also a triperiodic framework, with the point symbol {4.102} 2 {42.104} and the dmd topological type with uranium as 3-coordinated (3-c) nodes and tdc2− as either a 4-c node in its bis(μ 2 -κ1 O :κ1 O')-bridging mode, or a simple edge in the bis(κ2 O , O')-chelating mode. In both 1 and 2 , as in the previously described nmp complex, but not in [UO 2 (tdc)(dmf)] (dmf = N,N -dimethylformamide), coordination of a unidentate ligand disrupts the most common formation of diperiodic networks with tdc2− and tris-chelated uranyl, and promotes formation of frameworks in which channels accommodate the pendant, unidentate ligands. Complex 2 has a photoluminescence quantum yield of 3 % in the solid state, and its emission spectrum displays the typical vibronic progression with peak positions in the range usual for complexes with an O 5 equatorial uranyl environment; the "hot band" observed at room temperature disappears at 77 K. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amide and urea-based fluorometric receptors 1 and 2 were reported for I− and Hg2+ ions in aqueous medium. • Receptor 2 exhibited aggregation-induced emission at high pH. • Stern-Volmer plots and DFT studies explain fluorescence quenching with the presence of iodide ions. • Fluorescence turn-on phenomena were observed after adding Hg2+ ions to the iodide complexes of the receptors. • Practical utilities for detecting I− and Hg2+ ions were highlighted. Herein, we report pyrene-tagged amide and urea-based sugar derivatives 1 and 2 in a simple synthetic pathway to recognize I− and Hg2+ ions. Both molecules showed absorbance and fluorescence selectivity towards iodide ions in THF/H 2 O (7/3, v/v) medium. The selectivity and sensitivity of 2 for iodide ions are superior to 1 due to more H-bond donors in 2. Interestingly, fluorometric receptor 2 exhibited aggregation-induced emission (AIE) at higher pH with a remarkable fluorometric color change. The AIE phenomenon might be explained by the self-association of 2 after forming imine functionality in the alkali medium. The Stern-Volmer plot showed the fluorescence quenching constant of each receptor with an iodide ion and indicated the quenching pathway. The LODs of 1 and 2 for iodide ions were evaluated as 0.84 and 0.17 µM, respectively. The 1:1 binding stoichiometry of 1 or 2 with iodide was found from the Job plot and verified by measuring the complex mass. Further, the complexes of each receptor with I− ions can detect Hg2+ ions selectively by fluorescence turn-on method with low sensitivities (LODs: 0.008 µM for 1 and 0.01 µM for 2). DFT results were used to understand the binding mode of receptors 1 and 2 with iodide ions and the quenching process in the aqueous THF medium. The real application of the receptors was established for the recovery of iodide and Hg2+ ions from natural water samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • A TZPYZ sensor detects Ag+ ions using a photoluminescent "turn-on" mechanism. • In this spectrum, TZPYZ the probe shows absorbance at 410 nm and emission at 523 nm. • TZPYZ detects Ag+ ions UV–visible and photoluminescent at the lowest detection limits of 10.6 × 10−9 M and 6.74 × 10−9 M. • The designed probe TZPYZ has outstanding reversible and reproducible colorimetric & photoluminescent methods. • We analysed the probe TZPYZ and Ag+ ions using the human breast cancer cell line (MCF-7). In this work, a simple and versatile chemosensor receptor TZPYZ was synthesized through the combination of thiazole with pyrazine-2-carbohydrazide, resulting in a confirmed chemical structure via various analytical techniques including FT-IR, 1H, and 13C Nuclear Magnetic Resonance Spectroscopy, as well as High-Resolution Mass Spectroscopy analysis. TZPYZ exhibits specific colorimetric and photoluminescent responses to Ag+ ions in a solvent solution consisting of DMSO and H 2 O (7:3, v/v). Upon addition of Ag+ ions, noticeable changes in absorption spectra occur, resulting in a visible color change from pale yellow to blue. Additionally, an enhanced emission intensity with wavelength at 523 nm, when excited at 410 nm. Notably, TZPYZ demonstrated exceptional selectivity for Ag+ ions over other metal cations, achieving a detection limit (LOD) of 10.6 × 10−9 M and 6.74 × 10−9 M and using the UV–visible & photoluminescent titration method. Interference studies indicated minimal disruption from other metal ions on emission at 523 nm, highlighting TZPYZ discerning capability for Ag+ ions. With a binding affinity of 3.622 × 10−11 M−1, TZPYZ proved effective in detecting Ag+ ions across various water samples, showcasing its practical utility. The mechanism of interaction between TZPYZ and Ag+ ions was investigated using various experimental techniques, including Job's plot, Benesi-Hildebrand investigations, 1H NMR, and HRMS analysis. Test strips coated with TZPYZ showed selective detection of Ag+ ions, indicating its potential for on-site applications. Furthermore, DFT computations provided insights into the structural and electronic properties of TZPYZ and its complex with Ag+ ions, further elucidating the binding mechanism and stability of the complex. In addition, TZPYZ demonstrated compatibility with biological systems, as fluorescence imaging tests on MCF-7 breast cancer cells confirmed both its non-cytotoxic nature and its proficiency in detecting intracellular silver ions. Based on these findings, TZPYZ is highlighted as a highly sensitive and selective chemosensor for Ag+ ions, with promising applications in environmental analysis and bioimaging. [ABSTRACT FROM AUTHOR]

The electrochemical lithiation/delithiation (ELD) method with the typical active materials being LiFePO 4 and LiMn 2 O 4 , is the next generation technique for the selective lithium extraction from slat-lake brines owning to the advantages of high selectivity and excellent capacity and feasibility. However, the dissolution of LiFePO 4 /FePO 4 (LFP/FP) during the ELD is seldom studied and an inaccurate measurement method for dissolution may result in obtaining an incorrect feasible application range for LFP/FP. Here, electrochemical workstation-electrochemical quartz crystal microbalance (EW-EQCM) is first utilized in the brine system to acquire the in-situ dissolution behavior of LFP/FP redox couple and verify the inaccuracy principle of the dissolution measurement. Both experimental results and thermodynamic calculations demonstrated that the accurate dissolution ratios can only be obtained by iron ions and phosphates at pH < 2.7 and pH < 5.3, respectively, which is induced by the narrow soluble range of iron ions and the formation of Ca 5 (PO 4) 3 OH and Mg 3 (PO 4) 2 precipitation. In addition, the stable pH range of LFP and FP is 4 to 10 and 3 to 5, respectively, and the dissolution is caused by the formation of thermodynamically more stable metal ions, metal ion complexes, and metal ion hydroxides. At the optimum pH, the capacity can maintain 35 mg/g with average dissolution ratios of the cathode and anode lower than 0.1 %. This research sheds light on the accurate dissolution measurement range and method, dissolution mechanism and feasible application range of the LFP/FP redox couple. [Display omitted] • Feasible application range of LiFePO 4 /FePO 4 (LFP/FP) redox couple was proposed. • In-situ electrochemical analysis was first utilized to study dissolution behavior. • Thermodynamic calculations indicated the dissolution mechanism difference of LFP/FP. • The range of accurate dissolution calculated by irons was narrow. • A relatively accurate measurement method for the dissolution was clarified. [ABSTRACT FROM AUTHOR]

Magnesium ions (Mg2+) play an essential role in the metabolism and regeneration of bone tissue. Appropriate amounts of Mg2+ have been shown to promote osteogenic differentiation of bone-derived cells and angiogenesis of endothelial cells. However, the initial burst release of Mg2+ may compromise the osteogenic effect, so the controlled release of Mg2+ is the critical consideration of the magnesium-containing tissue-engineered bone materials. This study proposes a microsphere-hydrogel complex to enhance the sustained-release effect and prolong the release cycle of Mg2+. For the initial release of Mg2+, polylactic acid (PLA) microspheres containing MgO and MgCO 3 were fabricated with uniform morphology. Further microspheres were incorporated into the chitosan-based hydrogel to form microsphere- hydrogel complex for extended release. The complex demonstrated effective sustained release of Mg2+ over a period exceeding 28 days. In vitro cell experiments, CS/PLA@MgO-MgCO 3 significantly enhanced migration and osteogenic differentiation of MC3T3-E1. Meanwhile, it can facilitate the generation of blood vessels in HUVECs. In conclusion, the magnesium-loaded microsphere-hydrogel complex achieves excellent dual sustained-release properties with an extended-release cycle while enhancing vascularized osteogenic activity in vitro , showing promising prospects for clinical application in bone defect treatment. [ABSTRACT FROM AUTHOR]

Highly selective capture of Pb2+ is achieved by an barium-zinc-antimony-oxo cluster-based material in the presence of an excess of individual or multiple competing ions. The mechanism of the capturing and desorbing of Pb2+ ions is unveiled from the perspective of structural chemistry for the first time, that is, the ion exchange between Pb2+ and Ba2+ ions. [Display omitted] • A highly stable cluster-based material FJSM-BZA for lead remediation. • FJSM-BZA exhibits fast kinetic response and excellent selectivity for Pb2+. • Unprecedented SC-SC transformation during Pb2+ adsorption and elution. • Pb2+ capture mechanism illuminated at the molecular level for the first time. Efficient removal of Pb2+ from wastewater is of great significance for human health and environmental protection. However, Pb2+ capture from complex wastewater is still very challenging due to the strong competition with other metal ions. Herein, the highly selective removal of Pb2+ has been achieved by a cluster-based material, namely H 1.03 Ba 2.485 (H 2 O) 15 [Zn 2 Sb 12 (μ 3 -O) 8 (μ 4 -O) 3 (tta) 6 ]·8H 2 O (H 4 tta = tartaric acid) (FJSM-BZA). FJSM-BZA exhibits high adsorption capacity (199.29 ± 5.86 mg/g) and fast kinetic response (kinetic equilibrium is reached in 20 min) for Pb2+. In particular, even in the presence of competing ions Mn2+, Co2+, Ni2+, Cu2+, and Cd2+, FJSM-BZA maintains excellent selectivity for Pb2+ with removal rate much higher than that of other metal ions. The material after Pb2+ adsorption could be regenerated by a simple elution method. The unprecedented single-crystal-to-single-crystal (SC to SC) structural transformations during Pb2+ adsorption and elution are unveiled, which helps directly elucidate the distinctive mechanisms of ion exchange between Ba2+ and Pb2+. It is revealed that the strong coordination interactions of the active carboxyl groups at the periphery of the cluster with Pb2+ ions are the intrinsic driving forces for the ion-exchange. This work highlights the design and synthesis of crystalline metal-oxo cluster-based materials for highly selective removal of Pb2+. [ABSTRACT FROM AUTHOR]

A rapid, simple but sensitive analytical method for the simultaneous monitoring of heavy metal ions and illegal additives in complex samples remains lacking. We reported a difunctional capture–detection surface-enhanced Raman scattering (SERS) immunochromatographic assay (ICA) for the direct detection of the heavy metal residue Cd ion (Cd2+) and illegal additive clenbuterol (CLE) with high sensitivity and specificity herein. A novel magnetic SERS tag (Fe@RAu) with a Raman reporter molecule–embedded raspberry-like Au shell was fabricated via a one-step reduction reaction that not only simplified the fabrication of common magnetic SERS nanomaterials but also improved SERS activity to increase detection sensitivity. The difunctional SERS–ICA enabled the fast magnetic enrichment of the target small molecules in complex specimens and ultrasensitive and quantitative determination of CLE/Cd2+ on the two test lines of the ICA system. The limits of detection of the developed method for CLE and Cd2+ were as low as 0.48 and 1.88 pg/mL, respectively, and about 2000 and 500 times lower than those of conventional AuNP-based ICA strips. The excellent practicability of Fe@RAu–ICA for real food samples analysis was also demonstrated, revealing the potential of the proposed assay for rapid and on-site screening of small-molecule pollutants. [Display omitted] • A Raman reporter molecule–embedded magnetic SERS tag was reported for the first time. • Raman reporter–embedded magnetic tag was used as capture/detection difunctional tool for small molecule detection. • Simultaneous monitoring of heavy metal ions and illegal additives on SERS–ICA was first realized. • The detection limits for CLE and Cd2+ were as low as 0.48 and 1.88 pg/mL, respectively. [ABSTRACT FROM AUTHOR]

The conventional understanding about the specific ion effect from the coexisting electrolyte salts on the extraction and separation of target metal ions during liquid-liquid solvent extraction cannot explain some abnormal phenomena when more than one kind of background ions coexisting in the aqueous feed solutions to be separated. In this work, the specific ion effect of coexisting ions, Mg2+ and Al3+ as the example here, on extraction of Er3+ ion was investigated using gas bubble-supported organic liquid membrane. A very interesting phenomenon was noticed that, the difference in Er3+ extraction percentage was only 11.7 % in the Er-Mg solution system with addition of Al3+ ions or not, while it could reach 18.0 % in that of Er-Al with addition of Mg2+ ions or not. When Mg2+ and Al3+ coexisted simultaneously in the feed solutions, their specific ion effect on improving the extraction percentage of Er3+ was not equal to the sum of that when only single Mg2+ or Al3+ exists, respectively. Furthermore, a thinner organic liquid membrane supported by gas bubbles was in favor of enhanced interfacial enrichment of Er3+ and its diffusion mass transfer near the interface. During gas bubble-supported organic liquid membrane extraction, Mg2+ ions exhibited more obvious specific ion effect due to a weaker interaction with P507 molecules. However, a stronger hydration ability of Al3+ than Mg2+ ions induces a stronger competition of Al3+ with P507 molecules. Therefore, the coexistence of Mg2+ and Al3+ ions could play a synergistic role in enhancing enrichment of Er3+ on the basis of the mutual interference from the synergistic specific ion effect of coexisting Al3+ and Mg2+ ions. The research helps thoroughly understand the regulation mechanism on the synergistic specific ion effect for selective extraction of specified ions from the complex solutions containing multiple coexisting background ions. [Display omitted] • Interfacial effect from coexisting Mg2+ and Al3+ on extraction of Er3+ by gas BOLM. • Synergistic specific ion effect of coexisting Mg2+/Al3+ on enhanced Er3+ enrichment. • A thinner organic liquid membrane was in favor of enhanced interfacial enrichment. [ABSTRACT FROM AUTHOR]

• Trinuclear, 1D and 2D Cd–Ln heteronuclear complexes were synthesized. • The structures of the Cd–Ln complexes were regulated by co-ligand and Ln(III) ions. • The complex 2 exhibits corresponding Sm3+ ion characteristic emission. • The [CdL] unit is suitable for the sensitization of Sm3+ in solid and DMF. Four structurally different Cd-Ln heteronuclear complexes based on the linear chain ether Schiff base ligand (bis(3-methoxysalicylidene)-3-oxapentane-1,5-diamine (H 2 L) and the co-ligands 4,4′-bipyridine (bipy) or isonicotinate (IN), with composition [PrCd 2 L 2 (CH 3 COO) 2 ](NO 3)·CH 2 Cl 2 (1), {[SmCdL(bipy)(NO 3) 3 ]·CH 2 Cl 2 ·CH 3 CH 2 OH} n (2), [YbCdL(IN)(NO 3)(CH 3 COO)] n (3) and {[Nd 2 Cd 2 L 2 (IN) 2 (NO 3) 2 (CH 3 OH) 2 (CH 3 COO)](NO 3)} n (4), have been synthesized by interfacial diffusion methods. Structural regulation is achieved by changes in the co-ligands or Ln(III) ions of different radii: Single crystal X-ray analysis determined that 1 is a trinuclear cluster with the Pr(III) ion as a joint bridging of two CdL coordination units; 2 and 3 are both infinite one-dimensional zigzag coordination polymers consisting of CdLnL secondary units through coordination bridging bipy or IN; 4 is a two-dimensional graphene laminate structure formed by two types of CdNdL secondary units bridged by both IN and acetate simultaneously. In the solid state, the complexes 1–4 all exhibit fluorescence peaks based on H 2 L with blue shift and enhancement. The order of fluorescence peaks intensity of the complexes in N,N -dimethylformamide (DMF) solution is consistent with that in the solid state. Moreover, the corresponding characteristic emissions of Sm(III) ion in complex 2 can be observed in the fluorescence spectra in either solid state and DMF solution, indicating that [CdL] unit is suitable for the sensitization of Sm(III) ion. Four new Cd–Ln heteronuclear complexes based on the linear chain ether Schiff base ligand (bis(3-ethoxysalicylidene)-3-oxapentane-1,5-diamine have been synthesized, among which complex 1 is a trinuclear cluster, complex 2 and 3 are infinite one-dimensional zigzag coordination polymers, whereas 4 is a two-dimensional graphene laminate structure, which revealed that the introduction of co-ligands and the lanthanide contraction phenomenon can regulate the structures of the complexes to a certain extent. Fluorescence properties of 1 – 4 in the solid state and DMF solution at room temperature were also studied. It has been found that 2 exhibits corresponding Sm(III) ion characteristic emissions, suggesting that the [CdL] unit can sensitize Sm(III) ion. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Analysis of ion dynamics in Na 2 SO 4 -H 2 O using excess and 2D correlation Raman. • Evidence is provided for the formation of ion pairs and small ion clusters in Na 2 SO 4 -H 2 O. • MD calculations reveal that small ion clusters primarily consist of 2 and 3 ion pairs.. The ion association of salts aqueous solutions have long captivated the attention of researchers within the field of physical chemistry. In this paper, we have performed a comprehensive analysis of ion interactions in sodium sulfate (Na 2 SO 4) aqueous solutions using a combination of high-resolution techniques, including excess (ERS) and two-dimensional correlation (2DCRS) Raman spectroscopy in conjunction with molecular dynamics (MD) calculations. The Raman spectrum shows that two inflection points in the Raman shift of the O–H vibration are observed with the increase in Na 2 SO 4 concentration. Simultaneously, a new peak of the SO 4 2- vibration appears at first inflection point, representing the formation of ion association. Further analysis based on ERS and 2CRS reveals that these two inflection points correspond respectively to the formation of ion pairs (CIPs) and small ion clusters. Importantly, MD simulations confirm the above experimental results. Our study provides evidence for ion association and clustering in aqueous in salt ion aqueous solutions. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the morphologies, biocompatibility, and formation mechanism of lysozyme-hyaluronic acid complexes in the presence of various Hofmeister salts. During the complexation of lysozyme (Lys) and hyaluronic acid (HA), salts can control the formation of colloidal nanoparticles, amyloid-like aggregates, and amorphous aggregates. Circular dichroism spectra revealed that the α -helix content of Lys involved in complexation significantly increased from 21.40 % to 34.19 %, whereas the β -sheet content significantly decreased from 38.65 % to 24.42 % with increasing salt concentration. The fluorescence spectra indicated that the number of binding sites for HA and Lys decreased from 2.19 to 0.63 as the salt concentration increased from 0 to 300 mM, which was consistent with the different anion-specific effects (NaCl < NaBr < NaI). Interestingly, in vitro experiment results demonstrated that colloidal nanoparticles and amorphous aggregates have good biocompatibility, with NCM460 cell viability exceeding 85.92 %, whereas amyloid like aggregates exhibit certain cytotoxicity, with cell viability significantly reduced to 50.47 %. Overall, these findings provide a better understanding of the conformational changes of Lys involved in complexation with HA in the presence of salts, expanding its application in the food and pharmaceutical industries. • The presence of high concentration salts can completely inhibit the assembly process. • Salt ions control the microscopic morphology of formed LYS-HA complexes. • The formed amyloid-like aggregates exhibited highly toxic to the NCM460 cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metastable [Al(H 2 O) 6 3+]* cluster ions were prepared by Al-water reaction. • Metastable [Al(H 2 O) 6 3+]* cluster ions decompose H 2 O 2 into HO• in a full pH range. • [Al(H 2 O) 6 3+]* solution has an excellent recyclability up to ten cycles. • [Al(H 2 O) 6 3+]* solution has a lifetime of > 3 months. Our previous work indicated that hydroxyl radicals (HO•) exist in the filtrate of Al + acid + H 2 O 2 system. In this work, the behind mechanism was investigated in detail and a new catalyst for advanced oxidation processes (AOPs) was found for the first time. It was revealed that metastable hexacoordinated aluminum cluster ions ([Al(H 2 O) 6 3+]*), which are produced by Al-water reaction, can be as direct catalyst and decompose H 2 O 2 into HO• in a full pH range (2.5–12.0), and efficiently degrade and mineralize organic pollutants without precipitates. Of course, their catalytic activity in acidic aqueous solution is higher than that in neutral and alkaline solutions. Furthermore, [Al(H 2 O) 6 3+]* cluster ions have an excellent recyclability and their catalytic efficiency for generating HO• and degrading phenol and bisphenol A (BPA) did not decrease significantly even the cycling number was up to ten. Meanwhile, [Al(H 2 O) 6 3+]* cluster ions have a long lifetime and can keep their catalytic activity for more than three months under ambient condition. The present finding shows that Al3+ ions can be also as a cost-efficient catalyst for AOP technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • The inexpensive peptide-decorated C18 microspin columns were facilely prepared. • The peptide YYYCYCYYCR was discovered for the selective capture of arsenic (III) ion. • A method was developed for the high-throughput analysis of arsenic (III) ions in environmental water samples. In this study, a user-friendly, cost-effective, and high-throughput method was developed for the selective enrichment and accurate quantification of arsenic (III) ions using peptide-decorated C18 microspin columns, integrated with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) analysis. The manufacturing process of the peptide-decorated C18 microspin columns originated from C18 StageTips packing with 3 μm C18 beads, followed by decoration with the peptide YYYCYCYYCR, which contained the arsenic (III) ion-binding motif CXCXXC, where X represents any amino acid. The microspin columns were applied to selectively capture arsenic (III) ions in environmental water by forming arsenic (III)-peptide complexes. After elution and drying, the high m / z ions from these complexes were directly desorbed and ionized with MALDI-MS by the addition of the α-CHCA matrix solution, effectively reducing interference from matrix-related ions and small molecules in the low m / z range. The developed method demonstrated a linear range from 10 μg/L to 1500 μg/L, with a limit of detection of 0.7 μg/L. Remarkably, this method enabled rapid quantification of arsenic (III) ions in environmental water, averaging under one minute per sample, using only a small volume of 50 μL. The reported method for detecting arsenic (III) ions in environmental water offers a practical approach and holds promise for analyzing other emerging toxic elements in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • FA coordinates with Mg2+/Mg(OH) 2 to generate Mg-FA complex ions. • In strong alkaline medium, Mg(OH) 2 nanosheets aggregate to form Mg(OH) 2 -MNPs. • Mg(OH) 2 -MNPs-based surface-enhanced fluorescence was used for FA sensitive detection. We found an exciting fluorescence enhancement phenomenon of ferulic acid (FA) and magnesium ions in strong alkaline medium. In KCl/NaOH buffer solution with pH = 12.30, Mg2+ ions could coordinate with FA to generate Mg-FA complex ions and also combined with hydroxide ions to form Mg(OH) 2 nanosheets, and then the nanosheets further aggregated into Mg(OH) 2 -micro/nanoparticles (Mg(OH) 2 -MNPs). The Mg(OH) 2 -MNPs acted as potential matrix materials for surface-enhanced fluorescence (SEF). In this work, the fluorescence quantum yield and the fluorescence intensity of FA were significantly increased by about 50 times and hundreds of times by freshly formed Mg(OH) 2 -MNPs, respectively. Then, a highly sensitive method was developed for quantitative detection of FA. The fluorescence intensity at 440 nm under 370 nm light irradiation showed a good linearity with FA concentration in the range of 9.0 × 10−10 to 1.0 × 10–6 M (R 2 = 0.9984), and the limit of detection (at S/N = 3) was 2.7 × 10−10 M. And then a convenient method for FA detection by smartphone assisted was also proposed. These methods were applied for detecting FA in real samples, and the recovery rates were range from 98.3 % to 103.1 %. This work provided an effective way for improving FA analytical sensitivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • L-carnitine can effectively inhibit the dendrite and corrosion of Zn anodes. • L-carnitine ionic complexes build Zn2+ ion transport channels. • The zinc ion hybrid supercapacitors exhibit anti-self-discharge ability. Hydrogel-based zinc ion hybrid supercapacitors (ZHSCs) with high flexibility and appealing energy/power densities have attracted increasing attention in energy storage fields. However, the Zn dendrite growth, water-related side reactions, and fast self-charge issues lead to severe performance degeneration of hydrogel-based ZHSCs. Herein, a zwitterion L-carnitine (CN) was integrated into hydrogel electrolyte to construct a dendrite-free and anti-corrosive hydrogel-based ZHSC with a slow self-discharge rate. CN can enter the Zn2+ inner solvation sheath and isolate active water molecules from Zn anodes to induce homogeneous Zn2+ deposition and inhibit undesired side reactions. The CN ionic complexes serving as ion transport channels enable the Zn2+ to move along the migration channels, endowing the hydrogel electrolytes with a high Zn2+ transference number of 0.847. Besides, CN with zwitterionic groups forms electrostatic interactions with cations and anions, which prevents the diffusion of moveable ions from the electrode surfaces to hydrogel electrolytes, thus effectively prolonging the self-discharge time of ZHSCs. Accordingly, the hydrogel-based ZHSCs exhibit dendrite-free and corrosive-free behaviors on Zn electrodes after long-time operation, presenting a capacitance retention of 75 % after 2000 charge and discharge cycles at 1 A/g. The hydrogel-based ZHSC also display a long self-discharge time of 3h, which is more than 9 times that of the one without CN. This work provides guidance on the design of dendrite-free and anti-self-discharge hydrogel-based zinc ion energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Polysorbate 80 (PS80) is a non-ionic surfactant extensively utilized in biopharmaceutical formulations for stabilizing proteins. However, PS80 degradation has become a widespread concern throughout the industry over the past decade. In this work, the impact of most frequently employed pH/buffer systems on the stability of PS80 was assessed. PS80 degraded fastest in histidine buffer, followed by acetate and succinate buffers, whereas it remained stable in citrate, phosphate and tris buffers. When there was PS80 degradation, the extent of degradation was found to be pH-dependent. The predominant degradation pathway was oxidation mainly triggered by metal ions. The varying stability of PS80 across different pH/buffer systems was attributed to the role of buffer agents, which can either promote or inhibit the oxidation process through their interactions with metal ions. Specifically, buffers except histidine exhibited metal ion chelation similar to ethylenediaminetetraacetic acid (EDTA), which can suppress the oxidation of PS80, although the effectiveness of chelation varies to different extents. Furthermore, the binding capacity appeared stronger at higher pH in acetate and succinate buffers. Conversely, histidine was reported to form pro-oxidant complexes with metal ions to accelerate PS80 degradation, especially at higher pH levels. Our work for the first time offers a comprehensive understanding of PS80 oxidation in biopharmaceutical buffer systems. This provides a strong foundation for buffer and excipient selection in parenteral formulations. [ABSTRACT FROM AUTHOR]

We studied the emission of secondary ions using a cluster ion with MeV energy in transmission secondary ion mass spectrometry. The primary ions used were 0.6 MeV/atom C n +, where n ranges from 1 to 6. Single-layer graphene was used as a support membrane for depositing a biomolecular target of phenylalanine. Positive secondary ions emitted in both forward and backward directions were measured separately. We found that the yield of forward-emitted secondary ions was higher than that of backward-emitted secondary ions. Our results showed that the yield of secondary ions emitted in both directions increased as the size of incident cluster ions increased. This increase was non-linear and can be attributed to the track overlap effect of incident cluster ions. We also found a scaling parameter consistently describing the incident cluster size dependence of the forward and backward-emitted secondary ion yields. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal-earth ionosomes at the water/trifluorotoluene interface have been studied. • Single-entity electrochemistry shed properties of ionosomes. • It shed insights into the interface electric double layer through electrochemistry. • It provides potential application in the identification of high-pure water. Ionosomes are water clusters/droplets formed in an organic phase via the spontaneous assembly of ionic bilayers by hydrated cations or anions. The ionosomes formed by monovalent ions, i.e., Li+, Na+, K+, Cl−, etc., have been thoroughly investigated. Herein, single nanowater clusters (viz. ionosomes) in organic solutions, which are formed by the transfer of metal earth cations (i.e., Mg2+, Ca2+, Ba2+) into organic lipophilic electrolytes, were discovered using single-entity electrochemistry (SEE). The generation-fusion strategy involving two-step potentiostatic chronoamperometry was applied to investigate single Mg2+-ionosomes at the water/α,α,α-trifluorotoluene (w/TFT) interface. After an exciting potential forced the hydrophilic ion into the organic phase, a train of current spikes with information on the integrated charges, frequency, and duration were recorded to gain insight into the ionosomes. Variates were thoroughly investigated, including the exciting potential, exciting time, recording potential, size of the applied w/TFT interface, ion species, and concentration. These results suggest that: (1) the size of a single Mg2+-ionosome was revealed; (2) the fleshly formed ionosomes are mainly located on the organic side of the w/TFT interfacial surface instead of diffusing into the organic bulk; (3) when the interface decreases, fewer ionosomes form, and the size of the ionosomes decreases; (4) the mean charge carried by a single ionosome is positively related to the charge density of a single cation; (5) by alternating the recording potential, the negative zeta potential of Mg2+-ionosomes was revealed; (6) Mg2+-ionosomes can form when the aqueous solution contains only 2 μmol·L−1 Mg2+. This work thoroughly investigated hydrated metal earth ion clusters in the organic phase via SEE and provides insights into the interface electric double layer from the electrochemistry perspective. In addition to promoting the understanding of ionosomes, this strategy can provide potential applications to identify high-purity water. [ABSTRACT FROM AUTHOR]

For social security and safety, the sensitive explosives detection is crucial. Mass spectrometry (MS), a unique technique that may immediately reveal information about molecular structure, is considered as the "gold standard" in analytical science. Both science and technology now frequently employ MS-based techniques. This study developed an air-based low-pressure alternating current glow discharge (LP-acGD) ion source for MS to investigate its ionization efficiency in both positive and negative ion modes. The LP-acGD ion source gave O 3 −•, CO 3 −•, HCO 3 −, HCO 4 −, NO 2 − and NO 3 − ions that appeared at m/z 48, 60, 61, 77, 46 and 62, respectively in negative ion mode, some of these contributed to the formation of adduct ions. In positive ion mode, only protonated acetone, [Acetone + H]+ m/z 59, was detected at the beginning of the total ion current when 15 and 5 V were applied at orifices 1 and 2, respectively. However, the background ion signals were stabilized by protonated acetone and water cluster ions [(H 2 O) n + H]+ (n = 3, 4) as applied voltages were 40 and 0 V at orifices 1 and 2, respectively. Hydrogen peroxide, 3,4-dinitrotoluene, nitric acid, hexafluorobenzene, triacetone triperoxide and basil leaf were taken as model samples to investigate the efficiency of the ion source. In negative ion mode, H 2 O 2 and HNO 3 gave [H 2 O 2 +O 2 ]- m/z 66 and [HNO 3 +NO 3 ]- m/z 125, whereas 3,4-DNT and HFB exhibited mostly molecular ions. In positive ion mode, TATP yielded fragment ions of [C 3 H 6 O 2 +H]+ m/z 75 and [C 3 H 6 O 3 +H]+ m/z 91. The present method has been validated for detection and quantification of H 2 O 2 and HNO 3. Ion formation mechanisms are also discussed. Low pressure alternating current-glow discharge (LP-acGD) ion source for mass spectrometry. [Display omitted] • Fabrication of low pressure-acglow discharge ion source. • Charging effect plays vital role in formation of ions. • Air functions as carrier gas. • The ion source can be coupled with MS systems for analysis in real samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • Design and synthesis of dinitrophenyl and NBD platforms based fluorescent probes 1 and 2. • Highly selective and sensitive detection of Zn2+ in aqueous solution. • Extensive DFT simulations studies both on unbound and Zn2+ bounded sensors. • The formation of probes-Zn2+ complexes validated by both FT-IR and 1H NMR. • The LODs of 1 and 2 are 124 nM and 1.06 µM, respectively. The design and synthesis of two new fluorescent probes based on dinitrophenyl (1) and 7-nitrobenz-2-oxa-1,3-diazole (2) platforms is reported. Both probes, containing bis(pyridin-2-ylmethyl)amine as a receptor unit can efficiently detect zin ions (Zn2+) in aqueous solution, with limit of detections of 124 nM and 1.06 µM, respectively. Probe 1 and 2 led to 3-fold and 2.4-fold fluorescent enhancements, respectively, with the addition of Zn2+ which suggested that working mechanism of these probes is based on the inhibition of the photoinduced electron transfer from the electron donating receptor towards the excited fluorophore. Studying binding stoichiometry by job's plot suggested 1:1 complexation between the probe and Zn2+. Moreover, the formation of probes-Zn2+ complexes was validated by both FT-IR and 1H NMR wherein marked changes in the absorption frequencies as well as distinct downfield shifts in the resonance peaks of pyridine function along with the CH 2 group linked directly to the tertiary nitrogen of the DPA unit were observed. Density functional theory (DFT) calculations suggested that the electronic density of the HOMO in 1 was concentrated on the linker between DPA and dinitrophenyl, whereas the density of the LUMO was concentrated on dinitrophenyl moiety. Upon Zn2+ binding, the electronic density in HOMO and LUMO become more delocalized. However, in case of probe 2 the delocalization of electronic density does not appreciably occur. Based on DFT simulations, both sensors form thermodynamic stable complexes with Zn2+ ions. However, sensor 2 exhibited slightly better binding preference toward Zn2+ as compared to 1. The PET based probes exhibited good selectivity to detect Zn2+ in the presence of a variety of competing metal cations. These sensors have higher sensitivity and would be able to detect chronic level of Zn2+ in the freshwater (>1.84 μM) as permitted by the US EPA. [ABSTRACT FROM AUTHOR]

The behavior of metal ions is commonly studied in pure solvent although, in our daily life, these metals are involved in mixtures of solvents. In the present study, we investigated structures, relative stabilities and temperature dependance of solvated ferrous ion in water–ammonia mixture solvent at 0 K and at various temperatures ranging from 25 K to 400 K. All the calculations are performed at the MN15 level of theory associated with the aug-cc-pVDZ basis set. For deep understanding of binding patterns in solvated ferrous ion in water–ammonia mixture solvent, noncovalent interactions are presented based on the QTAIM analysis using AIMAll. Our results prove that the ferrous ion is more stable when it is solvated by ammonia instead of water. In addition, hydrogen bonds are weakened by the presence of ammonia molecules. The temperature dependence of the different obtained geometries indicates that from s = 6 (s is the sum of water and ammonia molecules around the ferrous ion), when the number of water molecules is almost equal to that of ammonia, the structures with coordination number 5 are dominant. However, the coordination number is six when there are a maximum water molecules (rich water solution) or maximum ammonia molecules (rich ammonia solution) around the ferrous ion (for s ≥ 6). The QTAIM analysis shows that there are two coordination bondings and four hydrogen bondings. Furthermore, it is found that the Fe 2 + ⋯ N coordination bondings are stronger than the Fe 2 + ⋯ O confirming that the ferrous ion prefers to be solvated by ammonia instead of water. [Display omitted] • Structures, relative stabilities and temperature dependence of solvated ferrous ion clusters in water–ammonia mixture solvent. • Binding patterns in solvated ferrous ions clusters in water- ammonia mixture. • Stability criteria of solvated ferrous ions clusters in water- ammonia mixture solvent. [ABSTRACT FROM AUTHOR]

This work reports on fabricating a flexible and reliable three-in-one solid-phase ocular sensor to perceive and confiscate the trace Pb2+, Hg2+, and Cd2+ using a structurally customized probe-anchored porous hybrid monolithic sensor. The dual combination of silica/polymer hybrid monolith was achieved from the bulk polymerization of 3-(trimethoxysilyl) propyl methacrylate (TSPM) and pentaerythritol trimethacrylate (PETMA), i.e., poly(TSPM-co-PETMA). The monolithic template delivered a well-ordered porous structure and greater surface area that enabled the regular impregnation of chromophoric probe (TAN), i.e., (E)-1-(thiazol-2-yldiazenyl) naphthalene-2-ol onto monolith surface for sensing target analytes under lower ppb levels. FE-SEM, HR-TEM, EDAX, SAED, p-XRD, FT-IR, TGA and N 2 isotherm were deployed to characterize the structural and exterior topographies of the hybrid sensor. The geometrically frozen TAN molecules onto the hybrid monolith form a charge transfer complex with the target ions, thereby rendering a consecutive color shift from light orange to brown for Pb2+, reddish maroon for Hg2+, and purplish pink for Cd2+. The sensor offered a linear response with metal ion concentrations ranging from 0.2 to 100 ppb with lower detection limit values of 0.42, 0.50, and 0.48 ppb for Pb2+, Hg2+, and Cd2+, respectively. The hybrid sensor affords distinct ion sensitivity and selectivity towards Pb2+, Hg2+, and Cd2+ with a quick response time of ≤ 80 s of contact. Furthermore, the sensor was tested with natural samples like environmental water and cigarette samples to validate the method's real-time monitoring ability. The resultant statistical data demonstrated that the proposed colorimetric sensor was renewable and more feasible for practical application. [Display omitted] • TAN probe hosted inorganic/organic hybrid monolith as a solid-phase optical chemo-sensor. • The hybrid monolith architecture of the sensor delivers effective metal ions dissemination probabilities. • The sensors render quick response kinetics towards sensing trace Pb2+, Hg2+, and Cd2+. • The hybrid opto-sensor is suitable for practical application in water and cigarette samples. • The sensor is affordable, reliable, recyclable, selective and ultra-sensitive. [ABSTRACT FROM AUTHOR]

• It is a great challenge to exhibit good antibiofilm activity of copper ions while minimize cell toxicity. • A metal-polyphenol-based catalytic system was designed to catalyze nitric oxide (NO) in combination with moderate photothermal/copper ions to systematically eradicate biofilms and promote wound healing process. • Subsequent treatments with moderate temperature (∼47℃) significantly enhanced bactericidal effect of low dose copper ions (∼1.2 μ g/mL) by deconstructing bacteria membrane. • The biofilm infection was successfully eradicated in only 250 min, significantly more effective than existing treatment methods. Copper ions are considered as a promising alternative to combat infected wound and accelerate wound healing. However, exhibiting good antibiofilm activity meanwhile minimizing cell toxicity remains a great challenge. To address this issue, we provide a sequential treatment strategy to combat biofilm infected wound with low copper ion (Cu2+) release (as low as 1.2 μg·mL−1). Polydopamine (PDA) adherent copper ion complex is constructed on thermoplastic polyurethane (TPU) to develop the Cu2+@PTPU nanofibers. With the application of Cu2+@PTPU wound dressing, nitric oxide (NO) gas is released by catalyzing endogenous donor, thereby rapidly eliminating more than 90 % biofilm biomass. Subsequent moderate photothermal treatment (∼47℃) significantly enhanced bactericidal effect by deconstructing bacteria membrane. As a result, the biofilm infection was eradicated in only ∼ 6h, significantly more effective than existing methods (∼24 h). Additionally, Cu2+@PTPU dressing not only exhibits excellent cell compatibility, but also promotes wound healing. In vivo study demonstrates that it reduces the level of inflammatory responses by 104 % and increases angiogenesis capacity by 115 %, compared with untreated group, thereby narrowing the wound site area by 72 % at day 14 after treatment. Overall, the Cu2+@PTPU dressing and sequential treatment strategy provide quick, safe, yet efficacious biofilm combating outcomes and facilitates rapid wound healing. [ABSTRACT FROM AUTHOR]

[Display omitted] • Elucidating the adsorbent materials of UES from a perspective of materials space-tectonics. • Evaluating UES materials based on adsorption capacity, selectivity, and durability. • Establishing the optimal "composition-structure-performance" relationship for efficient UES adsorbents. • Providing practical insights into the design of UES adsorbents by materials informatics and machine learning. Developing efficient adsorbents for uranium extraction from seawater (UES) poses a pressing challenge in the field of renewable energy. However, the low concentration of uranium in seawater (approximately 3.3 μg L-1), along with competition from various coexisting ions and the complex marine environment, poses challenges for UES. This review discusses the latest design and synthesis strategies for UES materials from the perspective of materials space-tectonics, encompassing "composition-structure-performance" with a focus on adsorption capacity, selectivity, and durability to facilitate identifying the optimal combination of parameters for individual building units. This approach holds the potential to overcome current limitations in UES material design for allowing the precise synthesis of target materials. This paper aims to provide practical insights into the design of UES adsorbents, offer perspectives on the development of the next generation of uranium adsorbents, and establish a theoretical foundation for UES adsorbent development. [ABSTRACT FROM AUTHOR]

• Preparation of two new complexes, [Co(CR) 3 (H 2 O)]Cl 2 and [Co(CR) 3 (H 2 O) 2 (2-NBA)]Cl 3. • The complexes have rod-shaped and nano-fibrous morphology respectively. • The oxidation states of cobalt ions in the complexes are +2 and +3 respectively. • The coordination process described here promises creatinine sensor development. Owing to creatinine's coordinating property with transition metal ions, its oxidation by 2-nitrobenzaldehyde, and the ability of the nitrite group to form chelate and bridging compounds with cobalt ions, different conditions-dependent pathways of reactions can be undertaken when any two of the three components (cobalt ion, creatinine, and 2-nitrobenzaldehyde) react. Bringing these three components together opens up multiple reaction possibilities. In this work, the effect of 2-nitrobenzaldehyde on a new complexation pathway of creatinine-cobalt has been explored, under some controlled conditions. As a result, a 4-coordinated complex, [Co(CR) 3 (H 2 O)]Cl 2, and a 7-coordinated complex, [Co(CR) 3 (H 2 O) 2 (2-NBA)]Cl 3 , were obtained, where CR= creatinine and 2-NBA= 2-nitrobenzaldehyde. P-XRD analysis confirmed the formation of new amorphous complexes and SEM analysis revealed their rod-shaped and nano-fibrous morphologies respectively. FTIR and Raman analysis established the coordination of cobalt ions with endocyclic nitrogen of creatinine and chelation with the nitro group of 2-NBA. From EDX analysis, close similarities between the experimental and theoretical elemental compositions of the complexes were determined. EPR analysis established the paramagnetic nature of the complexes. While DRS studies indicated different d -configurations of the cobalt ions in the complexes, CV and DPV confirmed their respective oxidation states to be +2 and +3. The coordination pathways described here can be put into a creatinine sensor development application. [Display omitted] [ABSTRACT FROM AUTHOR]

Heavy metals are one of the most important pollutants in the environment due to their toxic properties, accumulation, and indestructibility. So that when the metals enter the body of plants from natural and artificial sources, they accumulate in the organs and tissues. Therefore, in the present study, a sensitive and selective strategy is reported for the detection of cadmium(II) ions. To achieve this purpose, first sodium aluminate nanostructures were synthesized using a sol-gel method and green route. Then, using the nanostructures, a modified nanostructured sensor was designed. The characterization of the nanostructures was performed using various techniques. Next, the electrochemical behavior of the modified nanostructured electrode was investigated. The studies show the environment-friendly sensor has an enhanced voltammetric response than the unmodified sensor for cadmium(II) ions. After confirming the performance of the modified sensor, the analysis of cadmium(II) ions at the surface of the nanostructured modified electrode was investigated. Then, by differential pulse voltammetry (DPV) technique, the detection limit of cadmium(II) ions in optimal conditions was obtained at 1.10 nM with a broad dynamic linear range of 0.02–20.00 μM and 20.00–900.00 μM. Finally, the performance of the modified nanostructure sensor was investigated in food, biological and environmental samples, and acceptable results were obtained using the proposed method. • A green route for synthesis of sodium aluminate nanostructures. • Designing a novel nanostructured sensor for electrochemical studies of cadmium ions. • Determination of cadmium ions with low detection limit and broad linear range. • Sensitive and selective detection of cadmium ions in complex real samples. [ABSTRACT FROM AUTHOR]

The objectives of this study were to elucidate the effects of degree of methyl esterification (DM) and charge distribution of pectin on the stability of emulsions and to analyze bioaccessibility of curcumin incorporated in emulsions stabilized by pectins. Three commercial pectins, CP72 (DM72), CP50 (DM50), and CP7 (DM7), were used. MP50 (DM50) with consecutive demethylesterified galacturonic acid residues was prepared from CP72 via demethylesterification to induce different charge distributions. Emulsions containing curcumin were prepared and were stored for 30 days. The CP72 and CP50 emulsions remained relatively stable for 30 days. However, MP50 and CP7 were less effective at forming stable emulsions. When the pectin emulsions passed through each phase of the simulated gastrointestinal tract (GIT), the CP72 and CP50 emulsions retained their initial droplet structures after in vitro mouth and gastric digestion, whereas the MP50 and CP7 emulsions exhibited gel-like clusters, although the gel-like formation of MP50 was distinct from that observed in CP7. MP50 emulsion showed a high degree of final lipid digestion and high bioaccessibility of curcumin while CP72 emulsion displayed a low degree of final lipid digestion. CP50 exhibited low bioaccessibility of curcumin, which might have been contributed by its fast lipid digestion profiles. • MP50 with demethylesterified blocks was not effective in stabilizing the emulsion. • MP50 formed weaker gel clusters in ions than CP7, increased lipid digestion. • Lipid digestion can be delayed in emulsions stabilized with pectin. • Curcumin bioaccessibility varied based on DM and charge in pectin-stabilized emulsions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Herbs are utilized as a precursor of DVI-CDs-Cu. • DFT is used to assist in proving the possibility of material preparation. • A simple cascade catalytic reaction is constructed to enhance the scavenging of ROS. • DVI-CDs-Cu has potential usage in cigarette application scenarios. Oxidative stress is a growing concern, necessitating more effective antioxidants for complex environments. Herein, we developed a composite nanozyme, DVI-CDs-Cu, with exceptional antioxidant and antibacterial properties by utilizing DVI-CDs derived from Chinese herbs: Dandelion, Violet, and Isatis root, complexed with Cu2+ ions. The DVI-CDs with abundant surface functional groups exhibited excellent superoxide dismutase-like (SOD-like) activity while forming stable complexes with copper ions. The attached copper ions performed the peroxidase-like (POD-like) function and formed a cascade effect, greatly enhancing the antioxidant capacity of the DVI-CDs-Cu nanozyme and strengthening its antibacterial property. The nanozyme was able to comprehensively clear 90 % of reactive oxygen species (ROS) while killing approximately 98 % of bacteria. The potential application of the nanozyme as a ROS scavenger was demonstrated by exploring its application to cigarette filters, capable of eliminating approximately 80 % of ROS. This provides a new case for the design and development of CDs-metal ions synergistic bionano-enzymes. [ABSTRACT FROM AUTHOR]

• New polyamine bis(nitrophenylureylbenzamide) receptors (3A-3C) were synthesized. • Receptors 3A-3C form supramolecular aggregates with TBAX salts. • Receptors 3A-3C have interaction capacity towards anions and cations. • DFT-TD studies verified the experimental results obtained by UV–Vis. • DFT-TD allowed to propose the structure and supramolecular interactions in complexes. In this work the interaction of three new heterotopic polyamine bis(nitrophenylureylbenzamide) receptors ( R = 3A- 3C) with anions (A) and cations (M) was analyzed by UV–Vis spectroscopy and theoretical calculations. These receptors are highly pre-organized and form supramolecular complexes R-A at different ratios depending on the anion characteristics (1:1, 2:1, 3:1 and 4:3). The calculated log K values based on UV–Vis absorbance profiles and the structural information obtained from geometry optimizations using Density Functional Theory indicate strong stability in these complexes due to multiple intermolecular interactions between both species. Changes in the absorption band of receptors evidence the interaction with metallic ions forming complexes R-M (1:1) and the theoretical calculations predict the coordination with polyamine and amide groups adopting an aza-crown type conformation surrounding the Cu or Zn atoms. The subsequent formation of ternary complexes R-M-A with acetate showed different spectral changes for R-Cu and R-Zn ligands. The spectral changes with R-Cu ligands allowed to identified and calculated log K values for R-Cu-A and R-Cu-A 2 complexes. Moreover, the optimized structures for R-Cu-A and R-Cu-A 2 complexes show the coordination of one acetate ion with the metal center and a subsequent interaction of a second acetate with the urea groups in agreement with the experimental results. [Display omitted] [ABSTRACT FROM AUTHOR]

In the process of recycling cyanide solutions, the presence of metal-cyanide complex ions in gold leaching solutions leads to increased cyanide consumption and competition with gold for adsorption onto activated carbon. Consequently, the removal of metal cyanide complex ions from cyanide solutions is crucial. Polymer-quaternary ammonium salt aggregates (PAQs) have been used to precipitate metal cyanide complexes, but the polymer used is expensive and mainly aimed at single metal ion solution system. Therefore, in order to reduce the production cost and analyze the influence of coexisting ions on the removal effect, this study introduce Polyacrylamide (PAM) into a solution containing cetyltrimethylammonium bromide (CTAB), to form polymer-quaternary ammonium salt aggregates (PQAs) and enhance the removal efficiency of metal cyanide complex ions (Cu and Fe) from actual cyanide leaching solution of gold. CTAB forms micelle-like aggregates on the PAM backbone and the copper or iron cyanide complex ions adsorb onto the aggregates, which effectively removes copper and iron cyanide complex ions from actual cyanide solution. Meanwhile, the pH of cyanide solution has a great influence on the removal of metal cyanide complex ions, and the lower the pH, the better the removal effect. And the removal efficiency of copper and iron complexes ions can be obtained under the condition of pH 5.25, CTAB dosage 1 g/L, PAM dosage 100 mg/L, which was 95.49 % and 92.76 %, respectivity. Additionally, the longer the carbon chain of quaternary ammonium salt, the worse the removal effect of metal cyanide complex ions. SEM-EDS, FT-IR, and XPS analysis confirms the interaction between RN+ group of CTAB and metal cyanide complex ions, and also confirms that PAM participated in the precipitation process. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A cycloruthenated complex in the presence of F− could be used as an Ag+ colorimetric sensor. • The solution color and absorption spectral changes caused by Ag+ are different from the other metal ions. • The interaction mechanisms between metal ions and the complex in the presence of F− have been proposed. A cyclometalated ruthenium complex (1) using 2-phenylbenzimidazole as a C,N-ligand was developed as a colorimetric chemosensor to detect Ag+ ions. Upon the addition of Ag+ ions, the absorption spectra of complex 1 demonstrated no change in CH 3 CN solution. However, an excellent solution color change from dark-green to purple and absorption spectral change with a blue-shift of 27 nm (from 612 to 585 nm) were clearly observed after Ag+ ions were added to the solution of 1 with 2-fold of fluoride (denoted as 1 + F−). When Ag+ ions were replaced by other common metal ions, the solution color changed from green to red. Therefore, the solution of 1 + F− can be used to distinguish Ag+ from the other common metal ions. The absorption intensity at 612 nm exhibited a good linear correlation for the detection of Ag+ ion from 0 to 4 µM with a detection limit of 0.34 µM. According to the absorption and 1HNMR spectral changes of complex 1 , the reaction mechanism is proposed to be as a coordination between silver ion and the deprotonated nitrogen in imidazole. However, the interactions of other metal ions with 1 + F− are related to a proton transfer process. [ABSTRACT FROM AUTHOR]

Two uranyl ion complexes with a hemi-zwitterionic dicarboxylate ligand were synthesized, both crystallizing as diperiodic networks. One of them is luminescent and has one of the highest photoluminescence quantum yields among uranyl carboxylate complexes. [Display omitted] [UO 2 (L) 2 ] (1) and [(UO 2) 2 (L) 2 (C 2 O 4)] (2), where L– is 1,3-bis(carboxylatomethyl)-1H-benzimidazol-3-ium, are two uranyl ion complexes with a hemi-zwitterionic dicarboxylate ligand which have been synthesized under solvo-hydrothermal conditions and characterized by their crystal structure and luminescence properties. In both cases, the uranium atom is in a pentagonal-bipyramidal environment. Although diperiodic networks are formed in both cases, differences in the coordination mode of L– and the presence of bis-chelating oxalate anions generated in situ in 2 result in distinct topologies, hcb (with double edges) in 1 and V 2 O 5 in 2. Parallel-displaced π–π interactions occur in both cases but are particularly prominent in 2. While 2 is non-emissive under excitation at 420 nm, 1 gives a well-resolved spectrum with the maxima locations in agreement with those usual for O 5 equatorial uranyl environments. A photoluminescence quantum yield of ∼ 43 % has been measured for 1 in the solid state, this being among the highest values known for a uranyl carboxylate complex. [ABSTRACT FROM AUTHOR]

The high-magnesium gangue severely affects the melting performance and fluidity of slag in nickel matte smelting. To detect the adaptability when the CaO-modified slag for treating high-magnesia nickel sulfide concentrate in flash smelting, the synergistic effect of MgO and other oxides on the microstructure and physicochemical properties of slag were analyzed through molecular dynamics simulation associated with the experimental analysis. The results indicate that the MgO content increases from 5 wt% to 11 wt%, part of the Fe2+ ions in silicate are gradually replaced by Mg2+, and some of them are transformed into Fe3+ in the external atmosphere. Accordingly, the generated Fe3+ may destroy the bridge oxygen between Si4+-O2--Si4+ and more complex silicate ions will be dissociated into SiO 4 4+. As a consequence, the Q0 proportion in the modified high-magnesia smelting slag improved from 24.33% to 29.69%, and the n (BO/T) decreased from 1.45 to 1.29. However, when MgO content is high enough, SiO 4 4+ tetrahedron ions may attract Fe2+ and Mg2+ to form (Fe, Mg) 2 SiO 4 with a more robust interaction network structure, resulting in an adverse effect on melting temperature and ions diffusion coefficient. The modified nickel slags with 5–11 wt% MgO represent hospitable melting temperature less than 1320 °C, viscosity lower than 0.091 Pa s, and surface tension between 0.4811 N/m to 0.4838 N/m. In brief, the CaO-modified slag turned out to be conducive for treating high-magnesium nickel sulfide concentrates in flash matte smelting, especially for those containing MgO less than 7 wt%. [ABSTRACT FROM AUTHOR]

There is too much controversy and too little interdisciplinary analysis of the role of carbon electrodes in a wide range of electrochemical and electrocatalytic processes. Here we focus on vanadium redox flow batteries (VRFB), which play a central role in the transition to renewable energy sources in the electricity sector of the global economy. We used density functional theory (DFT) to determine the relationship between chemically and electrocatalytically active sites on the positive electrode and the effects of chemical surface modification that introduces a variety of oxygen functional groups. Carefully selected aromatic (Ar) model clusters were analyzed to assess the extent of the electron density accumulation on and around the free carbon sites at graphene edges. The results reveal trends that help to resolve the controversies surrounding the role of phenolic or carboxyl groups in the redox mechanism. We conclude, in agreement with other chemical and electrocatalytic reactions that involve oxygen transfer (e.g., CO 2 gasification or oxygen reduction reaction), that carbene-type edge carbon atoms are responsible for VO 2 + adsorption and reduction of V5+ to V4+ in VO2+. The presence of Ar-OH and Ar-COOH groups can actually inhibit the redox process as a consequence of hydrogen and/or oxygen migration to the adjacent active sites. The presence of Ar O groups, while affecting the electron density at the active sites, is confirmed to have a positive effect of stabilizing the free zigzag carbon sites in a triplet ground state. [Display omitted] [ABSTRACT FROM AUTHOR]