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Saltwater stands as the most prevalent liquid on Earth. Consequently, substantial interest has been directed toward its characterization, both as an independent system and as a solvent for complex structures such as biomacromolecules. In the last few decades, special emphasis was placed on the investigation of the hydration properties of ions for the fundamental role they play in numerous chemical processes. In this study, we employed multi-wavelength Raman spectroscopy to examine the hydration shell surrounding bromide ions in solutions of simple electrolytes, specifically lithium bromide, potassium bromide, and cesium bromide, at two different concentrations. Cation-induced differences among electrolytes were observed in connection to their tendency to form ion pairs. An increased sensitivity to reveal the structure of the first hydration shell was evidenced when employing ultraviolet excitation in the 228–266 nm range, under resonance conditions with the charge transfer transition to the solvent peaked at about 200 nm. Other than a significant increase in the Raman cross-section for the OH stretching band when shifting from pure water to the solution, a larger enhancement for the Raman signal of the H–O–H bending mode over the stretching vibration was observed. Thus, the bending band plays a crucial role in monitoring the H-bond structure of water around the anions related to the charge distribution within the first hydration shell of anions, being an effective probe of hydration phenomena. [ABSTRACT FROM AUTHOR]

Vanadium haloperoxidases have been studied to understand their mechanism and halide specificity. Crystal structures of vanadium bromoperoxidase enzyme complexes from Corallina piluifera, with vanadate and bromide and with phosphate and chloride, show significant displacement of loop residues 336–338 upon halogen binding. This shows a “closed position” of Leu337 locking the bromide ion in a hydrophobic environment favoring the vanadium peroxide reaction with the halogen by retaining the resulting hypobromite in the enzyme active site. The bound cofactor exists as a mixture of free vanadate and histidine553‐vanadate adduct. A mutant enzyme  Arg397Trp also has been crystallized with bound phosphate and its structure determined with and without the bound bromide ion. The precise positions of the bromine have been determined using its anomalous signal. The bromide binding site in the mutant enzyme is displaced by 2.5 Å resulting in a mixed population of the “open” and the “closed” forms of Leu337. This allows additional chloroperoxidase activity due to re‐positioning of the halogen ion 0.6 Å closer to the vanadate ion. These studies support the application of vanadium haloperoxidase enzymes for selective halogenation of important drug molecules. [ABSTRACT FROM AUTHOR]

Reaction of 2-amino-5-iodo­pyridine (5IAP) with concentrated HBr at room temperature yielded 2-amino-5-iodo­pyridinium bromide, C5H6IN2+·Br− or (5IAPH)Br. The complex formed pale-yellow crystals, which exhibit significant hydrogen bonding between the amino and pyridinium N—H donors and bromide ion acceptors. Halogen bonding is also observed. Similarly, reaction of 5IAP with cobalt(II) chloride in mixed HCl/HBr in 1-propanol yielded 2-amino-5-iodo­pyridinium (2-amino-5-iodo­pyridine-κN¹)bromido/chlorido­(0.51/2.48)cobalt(II), (C5H6IN2)[CoBr0.51Cl2.48(C5H5IN2)] or (5-IAPH)[(5IAP)CoCl2.48Br0.51], as blue block-shaped crystals. Two of the three halide positions exhibit mixed occupancy [Cl/Br = 0.797 (5):0.203 (5) and 0.689 (6):0.311 (6)], while the third position is occupied solely by a chloride ion. Extensive hydrogen and halogen bonding is observed. [ABSTRACT FROM AUTHOR]

Seawater chlorination has three main industrial uses: disinfection of water and installations, control of biofouling, and preventing the transport of aquatic invasive species. Once in contact with seawater, chlorine reacts rapidly with water constituents (e.g. bromide ions, ammonia, and nitrogen-containing compounds) to form a range of oxidative species (e.g. bromine and N-haloamines), termed "chlorine-produced oxidants" (CPOs) or "total residual oxidants" (TRO). The chemical nature of CPOs and their concentration are a function of two categories of parameters related to treatment modality (e.g. chlorine dose) and water quality (e.g. temperature, pH, ammonia concentration, and organic constituents). The chlorination process may result in continuous or intermittent releases of CPOs in seawater. The reactivity and potential ecotoxicity of CPO species largely depend on their physical and chemical properties. Therefore, evaluation of the biocidal effectiveness of chlorination and its potential impacts requires not only determining the sum of CPOs (via a bulk parameter), but also their chemical speciation. The aim of this article – which is the first of a trilogy dedicated to the chemical speciation of CPOs in seawater – is to provide an overview of current knowledge about chlorine chemistry in seawater and to discuss the biocidal efficacy and the environmental fate of resulting CPOs. The 2nd and 3rd articles delineate a comprehensive and critical review of analytical methods and approaches for the determination of CPOs in seawater. [ABSTRACT FROM AUTHOR]

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Bromine chemistry is responsible for the catalytic ozone destruction in the atmosphere. The heterogeneous reactions of sea‐salt aerosols are the main abiotic sources of reactive bromine in the atmosphere. Here, we present a novel mechanism for the activation of bromide ions (Br−) by O2 and H2O in the absence of additional oxidants. The laboratory and theoretical calculation results demonstrated that under dark conditions, Br−, O2 and H3O+ could spontaneously generate Br and HO2 radicals through a proton–electron transfer process at the air–water interface and in the liquid phase. Our results also showed that light and acidity could significantly promote the activation of Br− and the production of Br2. The estimated gaseous Br2 production rate was up to 1.55×1010 molecules cm−2 ⋅ s−1 under light and acidic conditions; these results showed a significant contribution to the atmospheric reactive bromine budget. The reactive oxygen species (ROS) generated during Br− activation could promote the multiphase oxidation of SO2 to produce sulfuric acid, while the increase in acidity had a positive feedback effect on Br− activation. Our findings highlight the crucial role of the proton‐electron transfer process in Br2 production; here, H3O+ facilitates the activation of Br− by O2, serves as a significant source of atmospheric reactive bromine and exerts a profound impact on the atmospheric oxidation capacity. [ABSTRACT FROM AUTHOR]

3-Monochloropropane-1,2-diol (3-MCPD) and glycidol are process contaminants found in foods, especially fats and oils. Flour dough improvers containing diacetyl tartaric acid esters of monoacylglycerides (DATEM) have been reported to react with chloride ions to form 3-MCPD in white bread; however, this finding remains controversial. In this study, we aimed to determine the effects of DATEM on 3-MCPD and glycidol formation in white bread. White bread was baked using distilled monoacylglycerides (MAG) or DATEM as emulsifiers, and 3-MCPD and glycidol contents were quantified via an indirect method using gas chromatography triple quadrupole mass spectrometry. Neither MAG nor DATEM increased the amounts of 3-MCPD and glycidol in white bread, suggesting that MAG and DATEM do not affect the formation of 3-MCPD and glycidol. Bread contains chloride ions as well as trace amounts of bromide ions, which originate from salt, fumigated wheat, and potassium bromate. Despite being formed from bromide ions, 3-monobromopropane-1,2-diol (3-MBPD) was not detected in the white bread. The results of this study demonstrate that the dough improvers MAG, DATEM, and bromide ions do not influence 3-MCPD, 3-MBPD, or glycidol formation during bread baking. These results provide important information for food safety management in bread baking with dough improvers. [ABSTRACT FROM AUTHOR]

Bidentate and tetradentate chalcogen bonding host systems with SeCF3 functions as σ-hole donors in close proximity at the alkyne functions of 1,8-diethynylanthracene and its syn-dimer were prepared in quantitative yield by tin-selenium exchange reactions of the corresponding trimethylstannyl precursors with ClSeCF3. The bidentate system shows chalcogen bonding interactions with THF, but does not bind halide ions. The tetradentate system cooperatively chelates chloride, bromide and iodide ions with its four C≡C–SeCF3 units by rotating the four σ-holes towards the halide ion. The structures of these halide ion adducts were determined by X-ray diffraction. The hydrobromide and -iodide salts of the ethyl derivative of Schwesinger's phosphazene superbase served as halide salts with very weakly coordinating cations. [ABSTRACT FROM AUTHOR]

Conformationally flexible tertiary amine – thiourea−urea catalysts 1 and 2 for the Mannich reaction between imines and malonate esters are efficiently inhibited by quaternary ammonium halides. NMR titrations, isothermal titration calorimetry (ITC) and NOE experiments showed that the catalysts bind chloride and bromide ions with relatively high affinities (K=103–105 M−1 in acetonitrile). The halide ions not only block the active site of the catalysts, but they also induce refolding into catalytically inactive conformations upon complexation in an allosteric‐like event. At substoichiometric inhibitor:catalyst ratios, the catalysts displayed hypersensitivity to the inhibitors, with overall rates that were lower than those expected from simple 1st order kinetics and 1 : 1 inhibitor:catalyst stoichiometry. To rationalize the observed hypersensitivity, different kinetic scenarios were examined. For catalyst 2 and the Takemoto catalyst (6), the data is consistent with 2nd order dependency on catalyst concentration, suggesting that a mechanism involving only a single catalyst in the catalytic cycle is not operative. For catalyst 1, an alternative scenario involving 1st order in catalyst and catalyst poisoning at low concentrations of 1 could also rationalize the hypersensitivity. Interestingly, inhibition of catalysts 1 and 2 by halide salts led to significant loss of enantioselectivity, in contrast to the Takemoto catalyst 6 which was inhibited but with essentially no change in enantioselectivity. [ABSTRACT FROM AUTHOR]

An composite adsorbent, Diatomite-KH560 was prepared by loading 7- (2, 3-epoxypropoxy)propytrimethoxysilane (KH560) on the surface of cheap and easily obtained diatomite, and its high-efficiency adsorption performance for iodide in aqueous solution was investigated. KH560 Was loaded on diatomite by immersion and hydrolysis, and contact time, temperature, pH, initial concentration and coexisting ions were investigated to evaluate the adsorption performance of Diatomite-KH560 for iodide. The result showed that Diatomite-KH560 with mild preparation conditions has high thermal stability, and the modification amount of KH560 is more than 13.3%. It takes a long time for Diatomite-KH560 to reach adsorption equilibrium for iodide, which may be controlled by several factors such as the diffusion of iodide in aqueous solution and the adsorption reaction rate on the adsorbent surface. The rate-controlling step is trans-formed into chemical adsorption process with the increase of temperature. In weak acid environment, the epoxy group on Diatomite-KH560 is protonated, forming positively charged adsorption sites, which adsorbs iodide through electrostatic attraction. According to the anion composition characteristics of brine, the effect of high concentration of chloride ion and trace amount of bromide ion and sulfate on the adsorption of iodide was investigated. It was found that the adsorption capacity of Diatomite-KH560 on iodide remained at 0.63 mg/g when the initial Cl/I reached 2 500 times. On the basis of the characterization results of EDS and FTIR, combined with the molecular structure of KH560, Diatomite-KH560 may achieve highly selective adsorption of iodide through the protonation of epoxy groups. [ABSTRACT FROM AUTHOR]

Bismuth halide perovskites have emerged as promising alternatives for sustainable and efficient photocatalysts for light‐induced organic transformations. Caesium bismuth halide perovskites (Cs3Bi2(ClxBr1‐x)9) with different ratios of chloride and bromide were synthesised using a one‐step solution process. These perovskites were then employed as photocatalysts for the photocatalytic oxidative coupling of benzylamine (BZA) to produce N‐benzylidenebenzylamine (BZI) under ultraviolet‐visible light radiation at ambient conditions. The incorporation of bromide ions into the chloride‐based perovskite resulted in a noticeable reduction in the bandgap, leading to an enhancement in the photocatalytic activity. Conversely, the addition of chloride ions within the bromide‐based perovskite was found to be beneficial for the material's photostability while simultaneously maintaining its high photocatalytic activity. The optimal compromise between the stability and photocatalytic activity for the BZI production was achieved using Cs3Bi2(Cl0.8Br0.2)9, being attained a total BZA conversion and the maximum BZI production with 100 % of selectivity after 6 hours of irradiation. The efficiency of this photocatalyst was ascribed to the highest current density observed during the photocurrent experiments, which improves the charge carrier mobility of the resulting material. [ABSTRACT FROM AUTHOR]

Fixing the greenhouse gas CO2 through epoxide helps to mitigate worldwide ecological troubles. The applications of metal‐free and solvent‐free catalysts remain a challenge for CO2 catalytic conversion. In this work, an array of quaternary ammonium salts derived from polyethyleneimine with hydroxyl groups ([PEI‐GDMAB‐Cn]Br) were constructed by the reaction of branched PEI with a molecular weight of 10000 and glycidyl alkyl dimethylammonium bromide. A range of experiments were designed to demonstrate that [PEI‐GDMAB‐Cn]Br can be considered as a valid metal‐free and solvent‐free homogeneous catalyst for the CO2‐epoxide cycloaddition reaction. Among of [PEI‐GDMAB‐Cn]Br, [PEI‐GDMAB‐C18]Br catalyzed the model reaction of CO2 and epichlorohydrin under optimized reaction conditions (T=80 °C, 1.0 atm CO2, catalyst 1 mol%, ECH 15 mmol, 16 h) and the conversion achieved at 97.5 %. Moreover, the catalyst exhibited stable reusability and broad substrate applicability, which was used in the following cycle succinctly, because of self‐separated properties by temperature control. The [PEI‐GDMAB‐C18]Br catalyzed reaction process was detected as a pseudo‐first‐order reaction after kinetic studies and an Ea was calculated to be 50.65 kJ/mol. A combinatorial catalytic mechanism of hydrogen bonding and bromide ions is suggested to explain the remarkable catalytic performance of this bifunctional catalyst. [ABSTRACT FROM AUTHOR]

Due to their unique properties, organosols of silver nanoparticles are widely used in optical and semiconductor devices, to produce electrically and thermally conductive films, as catalysts, antibacterial materials, etc. This work proposes a simple and highly productive method for the preparation of silver organosols, which have a metal concentration as high as 1800 g/L and contain spherical nanoparticles with low polydispersity and a median size of 9.1 nm. The method consists in the initial preparation of silver nanoparticle hydrosols with a concentration of higher than 30 g/L followed by the transfer of the NPs into an organic phase of o-xylene. A set of physical research methods has been employed to study the regularities of the extraction of silver nanoparticles with o-xylene in the presence of cetyltrimethylammonium bromide (CTAB) and ethanol and to determine the optimal process conditions, under which the extraction degree is as high as 62.5%. It has been found that bromine anions contained in CTAB molecules cause the aggregation of some amount of silver nanoparticles with the formation of silver metal sediment in the aqueous phase. According to X-ray photoelectron spectroscopy data, the sediment contains bromide ions (up to 4 at %) on the particle surface. Organosols synthesized under optimal conditions are stable for more than 7 months and withstand repeated cycles of drying and redispersing. Silver organosols have been used to obtain metal films with an electrical conductivity of about 68 500 S/cm, which increases to 412 000 and 509 500 S/cm (87.8% of the electrical conductivity of bulk silver) after thermal treatment at 150 and 250°C, respectively. [ABSTRACT FROM AUTHOR]

A thiophane‐catalyzed dibromination of olefins using NBS as the sole bromine source has been developed, providing a low‐cost and mild methodology for preparing vicinally dibrominated compounds from electron‐neutral or ‐deficient alkenes. The mechanistic investigation showed that 2,3‐dihydrothiophene generated in situ from the reaction of thiophane with NBS was the actual catalyst, which reversed the polarity of NBS to yield bromide ion. [ABSTRACT FROM AUTHOR]

The morphology-dependent localized surface plasmon resonance of gold nanostructures has been widely utilized for designing sensors. One method relies on the color change of gold nanoparticles upon etching. In previous work, TMB2+ oxidized from 3,3′,5,5′-tetramethylbenzidine (TMB) was found to etch gold nanorods (AuNRs), leading to a spectrum of different colors. However, the preparation of TMB2+ needs the addition of a strong acid and other harsh conditions. Herein, a new colorimetric biosensing platform was developed using urchin-like gold nanoparticles (AuNUs). Compared with AuNRs, the etching of AuNUs can happen under mild conditions by TMB+ at pH 6, protecting enzymes and proteins from denaturation. The role of CTAB surfactant was dissected, and its bromide ions were found to be involved in the etching process. Based on these observations, a one-step colorimetric detection of H2O2 was realized by using horseradish peroxidase and H2O2 to oxidize TMB. Within 30 min, this system achieved a detection limit of 80 nM H2O2. This work offered fundamental insights into the etching of anisotropic gold nanostructures and optimized the etching conditions. These advancements hold promise for broader applications in biosensing and analytical chemistry. [ABSTRACT FROM AUTHOR]

Anion exchange membranes (AEMs) play a critical role in anion exchange membrane-unitized regenerative fuel cells (AEM-URFCs). In this study, we investigated the effect of different membrane treatment processes on the performance of AEM-URFCs. By replacing bromide ions (Br−) with hydroxyl ions (OH−), we were able to greatly enhance cell performance. We treated a membrane electrode assembly (MEA) with KOH solutions of varying solvents and concentrations, which caused the AEM to swell and replace Br− ions with OH− ions. We found that the concentration of OH− ions in the KOH solution had a significant impact on Br− ion replacement. The MEA treated with 1.0 M KOH in a mixture of isopropyl alcohol (IPA) and deionized water (H2O) (25/75 vol%) had the lowest Br− ion content and exhibited a current density of 215.0 mA cm−2 at 0.5 V (fuel cell mode) and 65.0 mA cm−2 at 2.0 V (water electrolyzer mode). These findings can inform future research on AEM-based fuel cells and water electrolyzers by identifying an optimal membrane pretreatment process. [ABSTRACT FROM AUTHOR]

We study the Murray adaptation of the Noyes-Field five-step model of the Belousov-Zhabotinsky (BZ) reaction in the case when a tuning parameter r, which determines the level of the bromide ion far ahead of the propagating wave, is bigger than 1 and when the delay in generation of the bromous acid is taken into account. The existence of wavefronts in the delayed BZ system was previously established only in the monostable situation with r∈(0,1], the physically relevant bistable situation where r>1 (in real experiments r varies between 5 and 50) was left open. We complete the study by showing that the BZ system with r>1 admits monotone traveling fronts. Note that one of the stable equilibria of the BZ model is not isolated. This circumstance does not allow the direct application of the topological or analytical methods previously elaborated for the analysis of the existence of bistable waves. [ABSTRACT FROM AUTHOR]

We prove the existence of the minimal speed of propagation c ⁎ (r , b , K) ∈ [ 2 1 − r , 2 ] for wavefronts in the Belousov-Zhabotinsky system with a spatiotemporal interaction defined by the convolution with (possibly, "fat-tailed") kernel K. The model is assumed to be monostable non-degenerate, i.e. r ∈ (0 , 1). The slowest wavefront is termed pushed or nonlinearly determined if its velocity c ⁎ (r , b , K) > 2 1 − r. We show that c ⁎ (r , b , K) is close to 2 if i) positive system's parameter b is sufficiently large or ii) K is spatially asymmetric to one side (e.g. to the left: in such a case, the influence of the right side concentration of the bromide ion on the dynamics is more significant than the influence of the left side). Consequently, this reveals two reasons for the appearance of pushed wavefronts in the Belousov-Zhabotinsky reaction. [ABSTRACT FROM AUTHOR]

A set of new generation N/O donors, maleonitrile tethered, tetradentate heteroscorpionate modified Schiff base type ligands, 2-((E)-2-hydroxybenzylideneamino)-3-(pyridin-2-ylmethylamino)maleonitrile (H2LH), 2-((E)-2-hydroxy-5-nitrobenzylideneamino)-3-(pyridin-2-ylmethylamino)maleonitrile (H2LNO2), and 2-((E)-2-hydroxy-3-methoxybenzylideneamino)-3-(pyridin-2-ylmethylamino)maleonitrile (H2LOMe) were synthesized. These ligands were reacted with a stoichiometric amount of zinc acetate to afford corresponding mononuclear Zn complexes [Zn(LH)] (1H), [Zn(LNO2)] (1NO2), and [Zn(LOMe)] (1OMe) with excellent yields. All metal complexes and ligands were fully characterized using all possible spectroscopic tools, including single-crystal X-ray structure analysis in some cases. The 1H NMR spectral feature was well explained in terms of the electronic effect of the ligand's substitution at the phenyl ring. Novel monomeric Zn complexes supported by heteroscorpionate ligands were explored as effective catalysts to convert CO2 and CS2 to cyclic carbonates and thiocarbonates, respectively, via epoxide ring opening under mild and solvent-free conditions where tetrabutylammonium bromide (TBAB) was used as co-catalyst. The synthesized catalyst activates CO2 and CS2 at ambient conditions, whereas most of the reported catalysts require harsh conditions. Electronically, the Zn center in 1H was found to have the highest Lewis acidity, enabling better catalytic activity with respect to other Zn complexes. The probable mechanisms of catalytic activity for CO2 and CS2 activation were also explained. Mechanistically, the {Zn–Br} unit serves as a Lewis acidic platform that stabilizes the activated epoxide intermediate after ring opening by bromide ion and provides suitable nucleophiles for a further attack at the CO2/CS2 center. Exclusive cyclic carbonate/thiocarbonate formation was explained as the cyclization of activated CO2/CS2 product occurring at the Zn center before it is released as an acyclic intermediate. [ABSTRACT FROM AUTHOR]

Based on the existing literature, active chlorine‐mediated electrochemical oxidation has been extensively studied when Cl‒ is added or Cl‒ is already present in the water matrices, as well as when Cl‒ is released from the target organic pollutants during their degradation. However, no attempts have been published concerning the fate and role of bromide (Br‒) ions released during the anodic oxidation (AO) of organobromine compounds. Therefore, the AO of bromophenol blue dye (BPB) was investigated in a parallel plate flow reactor using a boron‐doped diamond (BDD) anode. The effect of the applied current on the color removal efficiency and mineralization of BPB solution was examined and compared with AO of phenol red (PR) which has a similar molecular structure to BPB (but without Br) in order to understand the role of Br heteroatoms on the mineralization of BPB. Faster and higher mineralization and discoloration were achieved when treated with BPB solution compared to PR under similar experimental conditions. This behavior was associated with the electrogeneration of BrO‒, from the heteroatom Br which is released as the bromide ion (Br‒), during the degradation of BPB. The active bromine species are formed via direct and indirect oxidation approaches which were proposed based on ion chromatography and linear scanning voltammetry analysis. [ABSTRACT FROM AUTHOR]

The Cu(II) complexes (H-5-FAP)2CuBr4 (1) and (H-2,3-dimpy)2CuCl4 (2) have been prepared and characterized structurally and magnetically (H-5-FAP = 2-amino-5-fluoropyridinium; H-2,3-dimpy = 2,3-dimethylpyridinium). They crystallize in the space groups P-1 and Pbcn, respectively, in comparison to their halido counterparts (H-5-FAP)2CuCl4 (1a) and (H-2,3-dimpy)2CuBr4 (2a) which crystallize in the space groups P21/c and P21/n. The differences in crystal packing, resulting in part from the difference in distortion of the CuX42− ions, create different magnetic lattices. Data for 1 were fit to the strong-rail ladder model resulting in a Curie constant of 0.400(8) emu-K/mol-Oe, J/kB-rail = −5.77(1) K and J/kB-rung = 3.17(3) K. Data for 2 were fit to the Curie-Weiss law resulting in a Curie constant of 0.398(1) emu-K/mol-Oe and θ = −0.11(4) K, indicating a virtual lack of magnetic exchange interactions. The structures and magnetic properties are compared to literature compounds and general trends noted. The differences in the chloride/bromide ions in the structure lead to significant differences in the packing in the cases of both 1 and 2, which result in differences in the antiferromagnetic exchange in both complexes and, in the case of 2, versus 2a, an elimination of the antiferromagnetic properties. [ABSTRACT FROM AUTHOR]

Structural and spectroscopic characterization (SXRD, IR, liq. N2 temperature Raman, UV) of hexaamminecobalt(III) dibromide permanganate, [Co(NH3)6]Br2(MnO4) (compound 1), are described. There is a 3D hydrogen bond network including N-H⋯O-Mn and N-H⋯Br interactions, which could serve as potential reaction centres for solid-phase redox reactions between the ammonia ligands and/or bromide ions as reductants and permanganate ions as oxidant agents. The effect of the nature of halogen ions on the structural and spectroscopic properties of [Co(NH3)6]Br2(MnO4) and the analogous chloride compound, [Co(NH3)6]Cl2(MnO4) (compound 2), are discussed in detail. [ABSTRACT FROM AUTHOR]

Perovskite hydrates have attracted extensive attention in diverse fields with intriguing optoelectronic properties, while their structural distortions usually cause large band gaps, which yield inferior light absorption and diminished optoelectronic device performance. Herein, modulating the structural distortion by steric hindrance effects is reported. Specifically, an N,N,N′,N′‐tetramethyl‐1,4‐phenylenediammonium (TMPD)2+ is adopted to template regular BiBr5 chains by interacting with bismuth bromide via weakening and reorienting H‐bonds, yielding a mixed 0D/1D (TMPD)2Bi2Br10.H2O with a narrow bandgap of 1.89 eV. The 0D/1D (TMPD)2Bi2Br10.H2O can be reversibly transformed into 0D (TMPD)2Bi2Br10 (Eg = 2.55 eV) with good cycling behavior. The (TMPD)2Bi2Br10.H2O turns out to be more stable than (TMPD)2Bi2Br10, and a mechanism involving vacancy‐assisted bromide ion migration is proposed for understanding the formation of BiBr5 chains. Density functional theory (DFT) calculations indicate that the (TMPD)2+ triggered hydration has a crucial impact on the downshift of the conduction band edge, thus decreasing the band gap. Moreover, the (TMPD)2Bi2Br10.H2O single crystal exhibits promising photoconductive behavior under a high moisture atmosphere, showing superiority over the conventional CH3NH3PbI3 perovskites that cannot survive moisture. This finding offers new insights into developing narrow band gap perovskite hydrates toward practical optoelectronic applications. [ABSTRACT FROM AUTHOR]

In bromido(pyrrolidine-κN)gold(I) bis(pyrrolidine-κN)gold(I) bromide, [AuBr- (pyr)]⋅[Au(pyr)2]Br (pyr = pyrrolidine, C4H9N), 2, alternating [AuBr(pyr)] molecules and [Au(pyr)2]+ cations are connected by aurophilic contacts to form infinite chains of residues parallel to the b axis. The chains are cross-linked by three N--H⋯Br_ hydrogen bonds and an Au⋯Br contact to form a layer structure parallel to the ab plane. Trichlorido(piperidine-κN)gold(III), [AuCl3(pip)] (pip = piperidine, C5H11N), 3, consists of molecules with the expected square-planar coordination at the gold atom, which are connected by an N--H⋯Cl hydrogen bond and an Au⋯Cl contact to form a layer structure parallel to the ac plane. The structures of bis(piperidinium) tetrachloridoaurate( III) chloride, (pipH)2[AuCl4]Cl, 4, and bis(pyrrolidinium) tetrabromidoaurate( III) bromide, (pyrH)2[AuBr4]Br, 6, are closely related but not isotypic. Compound 6 crystallizes in space group Ibam; the Au and two Br atoms of the anion lie in the mirror plane x, y, 0, whereas the bromide ions occupy special positions 0, 0.5, 0 and 0, 0.5, 0.25, with site symmetry 2/m. The NH2 group forms a hydrogen bond to one bromide ion, and also a three-centre hydrogen bond to the other bromide atom and to a metal-bonded Br atom. The packing involves chains of hydrogen-bonded pyrrolidinium and bromide ions parallel to the c axis, combined with a layer structure of [AuBr4]- and bromide anions, parallel to the ab plane and involving Au⋯Br and Br⋯Br contacts. Compound 4, however, crystallizes pseudosymmetrically in space group Iba2; two chlorine atoms of the anion lie on the twofold axis 0.5, 0.5, z, and there are two independent cations. The packing is closely similar to that of 6, but there are no N--H⋯Cl hydrogen bonds to metal-bonded chlorines. The contact distances Au⋯Cl are appreciably longer than their Au⋯Br counterparts in 6, whereas the Cl⋯Cl contact is much shorter than Br⋯Br in 6. Tribromido(piperidine-κN)gold(III) crystallizes as its dichloromethane solvate, [AuBr3(pip)]•CH2Cl2, 7. It too displays a square-planar coordination at the gold atom. The packing involves hydrogen bonds N--H⋯Br, stacking of neighbouring AuBr3 units by Au⋯Br contacts, and a short Br⋯Br contact; these combine to form a layer structure parallel to the ac plane. [ABSTRACT FROM AUTHOR]

Members of the Gulf Cooperation Council countries Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates rely on desalination to produce water for domestic use. Desalination produces brine that may intrude into the aquifers to pollute the fresh groundwater because of the concentration gradient and groundwater pumping. Modeling the trends of saltwater intrusion needs theoretical understanding and thorough logical experimentation. The objective of this exercise was to understand the phenomenon of saltwater intrusion using an existing set of data analyzed with the convective–diffusion equation and the two-region mobile–immobile solution model. The objective was achieved by optimizing non-measurable solute transport parameters from an existing set of data generated from a series of logical miscible displacements of potassium bromide through sepiolite minerals and curve-fitting simulations. Assumptions included that solute displacements through sepiolite porous media and the related simulations represented the phenomenon of saltwater intrusion under non-equilibrium conditions of porous media mimicking the aquifers. Miscible displacements of potassium bromide were observed from a column of 2.0–2.8 mm aggregates of sepiolite over 4 ranges of concentration and at 11 displacement speeds under saturated vertical flow deionized water and vice versa. Breakthrough curves of both bromide and potassium ions were analyzed by a curve-fitting technique to optimize transport parameters assuming solute movement was governed (i) by the convective–diffusion equation and (ii) the two-region mobile–immobile solution model. Column Peclet numbers from the two analyses were identical for potassium ions but those for bromide ions were c. 60% greater from the two-region model than from the convective–diffusion equation. For the two-region model, dispersion coefficients were well defined and remained unchanged from the convective–diffusion equation for potassium ions but decreased for bromide ions. Retardation factors for bromide ions were approximately the same, but those for potassium ions, though > 1, were poorly defined. In order to design mitigation strategies for avoiding groundwater contamination, this study's findings may help model groundwater pollution caused by the activities of desalination of seawater, which produces concentrated liquid that intrudes into the coastal aquifer through miscible displacement. However, robust saltwater intrusion models may be considered in future studies to confirm the results of the approach presented in this exercise. Field data on the groundwater contamination levels may be collected to compare with simulated trends drawn from the saltwater intrusion models and the curve-fitting technique used in this work. A comparison of the output from the two types of models may help determine the right option to understand the phenomena of saltwater intrusion into coastal aquifers of various characteristics. [ABSTRACT FROM AUTHOR]

Upon white light illumination, the growth of the budding yeast Saccharomyces cerevisiae was extremely impaired only in the presence of iodide ions, but not fluoride, chloride and bromide ions. Action spectroscopy revealed that the maximum wavelength of the light is around at 373 nm, corresponding to the UVA region. Using a genetic approach, several genes, including OPY1, HEM1, and PAU11, were identified as suppressors of this growth inhibition. This iodide-dependent UVA-triggered growth inhibition method, along with its suppressive molecules, would be beneficial for understanding cell growth processes in eukaryotes and can be utilized for medium sterilization using UVA light. • The growth of Saccharomyces cerevisiae was extremely impaired only when both iodide ions and white light were present. • The maximum wavelength of the light is at 373 nm, corresponding to the UVA region. • Several genes including OPY1, HEM1 and PAU11 were identified as suppressive molecules. [ABSTRACT FROM AUTHOR]

Abstract Based on the existing literature, active chlorine‐mediated electrochemical oxidation has been extensively studied when Cl‒ is added or Cl‒ is already present in the water matrices, as well as when Cl‒ is released from the target organic pollutants during their degradation. However, no attempts have been published concerning the fate and role of bromide (Br‒) ions released during the anodic oxidation (AO) of organobromine compounds. Therefore, the AO of bromophenol blue dye (BPB) was investigated in a parallel plate flow reactor using a boron‐doped diamond (BDD) anode. The effect of the applied current on the color removal efficiency and mineralization of BPB solution was examined and compared with AO of phenol red (PR) which has a similar molecular structure to BPB (but without Br) in order to understand the role of Br heteroatoms on the mineralization of BPB. Faster and higher mineralization and discoloration were achieved when treated with BPB solution compared to PR under similar experimental conditions. This behavior was associated with the electrogeneration of BrO‒, from the heteroatom Br which is released as the bromide ion (Br‒), during the degradation of BPB. The active bromine species are formed via direct and indirect oxidation approaches which were proposed based on ion chromatography and linear scanning voltammetry analysis.

Phase transformation represents a fascinating way to tune the structural and optical properties of metal halide perovskites. Macrocyclic cyclodextrin could trigger transformation of cesium copper bromide, driven by strong interactions of the macrocyclic hydroxyl groups with the perovskite cesium and bromide ions. [ABSTRACT FROM AUTHOR]

Besides inherent fullerene-like hollow spheres, the metallasupramolecular chemistry of pentaphosphaferrocenes and CuBr2 afforded a conceptually new product, a compact 3.2 nm sized supramolecule [{1d}6(CuBr)32(CH3CN)6] formed by six largest pentaphosphaferrocene units [CpBIGFe(η5-P5)] (1d: CpBIG = η5-C5(4-nBuC6H4)5) so far and a framework of 32 copper and 32 bromide ions. [ABSTRACT FROM AUTHOR]

Besides inherent fullerene-like hollow spheres, the metallasupramolecular chemistry of pentaphosphaferrocenes and CuBr2 afforded a conceptually new product, a compact 3.2 nm sized supramolecule [{1d}6(CuBr)32(CH3CN)6] formed by six largest pentaphosphaferrocene units [CpBIGFe(η5-P5)] (1d: CpBIG = η5-C5(4-nBuC6H4)5) so far and a framework of 32 copper and 32 bromide ions. [ABSTRACT FROM AUTHOR]

A number of porous polymeric solid phase extracting sorbents were tested for selective removal of organic compounds from aqueous solutions in which bromide ions are to be determined, and the best were recommended. A methodology was developed to achieve selectivity as to bromide ion, the concentration of which should not change in the sample during sample pretreatment. In order to selectively remove dissolved organic compounds from water matrix intended for analysis for bromide, sample acidification to pH 2.0 is recommended followed by sample filtration through the reverse-phase sorbent of LC-18 type. In these conditions, 20 mg/dm3 of fulvic acid characteristic of Dnipro River water are effectively separated from 0.1 mg/dm3 Br-with minimal losses of the latter. Sample acidification promotes the formation of molecular non-dissociated forms of organic compounds in solution, which are effectively separated from bromide ions on reverse-phase sorbents. Artesian water and sea water contaminated with oil spills were analyzed using passing through LC-18 sorbent. Results of natural water analysis by photometric and ICP-MS methods prove the applicability of the approach proposed. [ABSTRACT FROM AUTHOR]

In this study, the spent bleaching earth carbon (SBE@C) was modified with iron to obtain the iron-modified spent bleaching earth carbon (defined as FexOy-SBE@C) to remove bromate. The pseudo-second-order kinetic model and Langmuir model could well fit the bromate removal process. When the temperature was increased from 25 to 45 °C, bromate removal efficiency increased, and FexOy-SBE@C exhibited the highest bromate removal capacity of 521.82 mg/g at 45 °C. The effect of coexisting anions was investigated, and their adverse effects decreased in the order of PO43->NO3->SO42-. The higher the concentration of coexisting ions, the greater their inhibitory effect on bromate removal. By studying the effect of pH, it was found that the bromate removal was the highest at pH = 3. Characterization analysis confirmed that the iron was successfully loaded on the surface of SBE@C. The main mechanism for bromate removal by FexOy-SBE@C was the reduction of zero-valent iron and divalent iron with bromate to form the bromide ion. Overall, FexOy-SBE@C is a high-performance material for bromate removal. [ABSTRACT FROM AUTHOR]

Gold(I) complexes with N‐heterocyclic carbene ligands functionalized with a pendant phosphonium moiety were synthesized by simple procedures. In particular, the simple addition of LiBr salt in the reaction media allows the formation of the NHC gold(I) mononuclear complexes, whilst in the absence of excess bromide ions the deprotonation of the methylene group in alpha position to the phosphonium group occurs, allowing the isolation of the dinuclear complexes with two C,C‐bridging NHC‐phosphonium ylide ligands. The complexes were characterized in solution with NMR spectroscopy and ESI‐MS spectrometry, as well as in the solid state by means of single crystal X‐ray diffraction analysis. Mononuclear gold(III) species were also isolated by Br2 oxidative addition to the mononuclear gold(I) species and fully characterized. Preliminary results of the biological effects on MCF7 cancer cells are also reported. [ABSTRACT FROM AUTHOR]

Trihalomethanes (THMs) are the first disinfectant by-products in the drinking water distribution network and are classified as potential carcinogens. The presence of THMs in chlorinated water depends on the pH, water temperature, contact time between water and chlorine, type and dose of disinfection, bromide ion concentration, and type and concentration of natural organic materials (NOMs). In the present study, the formation of THMs was evaluated by six simple and easy water quality parameters and modeled by an artificial neural network (ANN) approach through five water distribution networks (WDNs) and the Karoun River in Khuzestan province. The results of this study that was conducted from October 2014 to September 2015 showed that THM concentration ranged in five WDNs, including Shoushtar, Ahvaz (2), Ahvaz (3), Mahshahr, Khorramshahr, and total WDNs through N.D.–9.39 µg/L, 7.12–28.60, 38.16–67.00, 17.15–90.46, 15.14–29.99, and N.D.–156, respectively. The concentration of THMs exceeded Iran and EPA standards in many cases in Mahshahr and Khorramshahr WDNs. Evaluation of R2, MSE, and RMSE showed the appropriate correlation between measured and modeled THMs, indicating a reasonable ANN potential for estimating THM formation in water sources. [ABSTRACT FROM AUTHOR]

Dithienylethene-strapped calix[4]pyrrole is isomerized by 300/630 nm light between ring-open and -closed isomers, which affects the size of the anion binding site. Where for chloride this results in only a small change in affinity, that of the larger bromide and iodide ions is majorly affected, resulting in altered selectivity. [ABSTRACT FROM AUTHOR]

The evidence on deciphering nucleation and growth of cesium lead halide perovskite crystals, and establishing the phase diagram of cesium lead halide perovskites of different dimensions is still lacking. In this work, a facile method for the synthesis of cesium lead bromide crystals of different molecular level dimensions at room temperature is presented by varying the OA/OAm ratios without changing the proportions of Cs and Pb precursors. Bromide ions are gradually released in the systems through the gamma‐ray radiation chemistry of bromobenzene. As the volume ratios of OA/OAm increase, different products such as CsBr, Cs4PbBr6 (0D), white δ‐CsPbBr3 (1D), γ‐CsPbBr3 (3D) associated with PbBr2 sheets, and γ‐CsPbBr3 are obtained in order. 1D δ‐CsPbBr3 can be transformed into 2D CsPb2Br5 through CsBr stripping in water. The phase diagram established in this work is helpful for understanding the nucleation and growth mechanism of Cs–Pb–Br perovskite crystals of different dimensions. The nucleation of Cs–Pb–Br perovskite crystals is driven by the supersaturation of either CsBr or PbBr2 caused by varying OA/OAm ratios, i.e., 0D Cs4PbBr6 at the supersaturation of CsBr, while 3D γ‐CsPbBr3 at the supersaturation of PbBr2. 1D perovskite is the intermediate state between 0D and 3D perovskites. [ABSTRACT FROM AUTHOR]

Bromide ions are inevitable in aquatic environment and influence the degradation of contaminants in non-radical based advanced oxidation processes, but the role of reactive bromine species (RBS) remain obscure. This study investigated the role of bromide ions in the degradation of methylene blue (MB) during the base/peroxymonosulfate (PMS) process. The formation of RBS as a function of bromide ions were evaluated using a kinetic modelling. Bromide ions were shown to play crucial roles in MB degradation. Increasing the dosage of NaOH and Br- increased the transformation kinetics of MB. However, brominated intermediates which are more toxic than precursor MB were generated in the presence of Br-. The formation of adsorbable organic halides (AOX) was enhanced by elevating the dosage of Br-. The formation of AOX was even more significant in the absence of NaOH, and the AOX values decreased with the increasing alkalinity. The kinetic model indicated that the dominant reactive species formed in the base/PMS/Br- process are 1O2 and HOBr, and Br2 in the Br-/PMS process. Therefore, the influence of bromide ions should be taken into consideration in the application of the base/PMS process for organic matters in bromide-containing natural water. Strategies should be developed to make full use of RBS for the abatement of organic pollutants and to reduce the formation of AOX. This study reveals that in the treatment of saline wastewater by PMS-based processes, increasing the amount of NaOH may be an effective strategy to inhibit the accumulation of AOX. [ABSTRACT FROM AUTHOR]

Semiconductor photocatalytic performances can be modulated through morphology modification. Herein porous hierarchical BiOBr microspheres (BiOBr-MS) of ~3 μm was firstly self-assembled without the assistance of a template via a facile solvothermal synthesis in triethylene glycol (TEG) at 150 °C for 3 h. KBrO3 was exploited as a bromine source, which slowly provided bromide ions upon reduction in TEG and controlled the growth and self-assembly of primary BiOBr nanoplates. The addition of PVP during solvothermal synthesis of BiOBr-MS reduced the particle size by about three-fold to generate BiOBr sub-microspheres (BiOBr-sMS) of <1 μm. BiOBr-sMS exhibited significantly higher photocatalytic activity than BiOBr-MS for aerobic photooxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) under simulated sunlight irradiation (conversions of BzOH (50 mM) over BiOBr-sMS and BiOBr-MS were, respectively, 51.3% and 29.6% with 100% selectivity to BzH after Xenon illumination for 2 h at 25 °C). The photogenerated holes and ·O2− were found to be main reactive species for the BzOH oxidation over BiOBr spheres by scavenging tests and spin-trapping EPR spectra. The higher photocatalytic activity of BiOBr-sMS was attributed to its more open hierarchical structure, efficient charge separation, more negative conduction-band position and the generation of larger amounts of ·O2−. [ABSTRACT FROM AUTHOR]

A highly selective one-pot microwave-assisted synthesis of 9-methoxynaphtho[1,2-b]benzofuran was obtained by treating 1-naphthol with 1-bromo-4-methoxy-2-nitrobenzene and two molar equivalents of potassium tert-butoxide in dimethyl sulfoxide. The selectivity in the production of the title compound was addressed by the suitable position of the bromine and nitro group on the aryl reagent. Moreover, we highlight how the nitro group plays a dual role, as activator in the first nucleophilic substitution with the release of bromide ion and then as the leaving group in the furan cyclization. Eventually, the product was structurally characterized by MS and extensive NMR analyses. [ABSTRACT FROM AUTHOR]

Seawater desalination is practiced in many coastal countries, which is accepted as clean water by the general populations. The untreated seawater reported high concentrations of bromide (50,000 – 80,000 µg/L) and iodide (21 – 60 µg/L) ions, which are reduced to non-detectable levels during thermal desalination while the concentrations of bromide and iodide ions were reduced to 250–600 µg/L and < 4–16 µg/L, respectively during reverse osmosis processes. During the treatment and/or disinfection, many brominated and iodinated disinfection byproducts (Br-DBPs and I-DBPs) are formed in desalinated water, some of which are genotoxic and cytotoxic to the mammalian cells and possible/probable human carcinogens. In this paper, DBPs' formation in desalinated and blended water from source to tap, toxicity to the mammalian cells, their risks to humans and the strategies to control DBPs were investigated. The lifetime excess cancer risks from groundwater, and desalinated and blended water sourced DBPs were 4.15 × 10–6 (4.72 × 10–7 – 1.30 × 10–5), 1.75 × 10–5 (2.58 × 10–6 – 5.25 × 10–5) and 2.59 × 10–5 (4.02 × 10–6 – 8.35 × 10–5) respectively, indicating higher risks from desalinated and blended water (2.56 and 4.51 times respectively) than groundwater systems. Few emerging DBPs in desalinated/blended water showed higher cyto- and genotoxicity in the mammalian cells. The findings were compared with safe drinking water standards and strategies to produce cleaner desalinated water were demonstrated. [ABSTRACT FROM AUTHOR]

An effective approach for tuning CO2 adsorption, activation and transformations of various epoxides in CO2 fixation reactions is introducing functional groups into the pores of metal‐organic frameworks (MOFs) through ligand modification. Herein, a novel ionic ligand, 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene‐biphenyl‐4,4′‐dicarboxylic acid (H2BPDC−[TBD]+Br−), was synthesized to construct derivatives of the cationic guanidinium‐containing Zr‐MOF (UiO67‐[TBD]+Br−) with free bromide ions, as multifunctional heterogeneous catalysts. The materials were characterized comprehensively by multiple techniques such as PXRD, FTIR, TGA, SEM, EDS, 1H NMR, 13C NMR, mass spectrometry (MS), elemental analysis, as well as N2 and CO2 adsorption measurements. The synthesized UiO67‐[TBD]+Br− exhibits an efficient heterogeneous catalytic performance in the CO2 fixation reaction with epoxides, with high yield and selectivity, under mild conditions (0.1 MPa CO2, 80 °C, without co‐catalyst and solvent). In addition, these catalysts display good thermal stability, recyclability and could be reused at least five times without a significant decrease in their catalytic performance. [ABSTRACT FROM AUTHOR]

Supercapacitors have attracted tremendous attention due to their merits of excellent cycling stability, remarkable power density and low cost. Nevertheless, the low energy density of supercapacitors has encumbered their further development for practical applications. Development of advanced high-energy supercapacitors is considered to be of crucial importance. In this work, the capacitance of MOF-derived carbon-based supercapacitor is dramatically improved by addition of soluble redox-active LiBr electrolyte additive. The post analysis of this redox-active electrolytes reveal that the Br−/Br2 couple are the main pseudocapacitance contribution in the early cycles stages (

Understanding the behavior of surfactants at interfaces is crucial for many applications in materials science and chemistry. Optical tweezers combined with trajectory analysis can become a powerful tool for investigating surfactant characteristics. In this study, we perform trap-and-track analysis to compare the behavior of cetyltrimethylammonium bromide (CTAB) and cetyltrimethylammonium chloride (CTAC) at water–glass interfaces. We use optical tweezers to trap a gold nanoparticle and statistically analyze the particle's movement in response to various surfactant concentrations, evidencing the rearrangement of surfactants adsorbed on glass surfaces. Our results show that counterions have a significant effect on surfactant behavior at the interface. The greater binding affinity of bromide ions to CTA+ micelle surfaces reduces the repulsion among surfactant head groups and enhances the mobility of micelles adsorbed on the interface. Our study provides valuable insights into the behavior of surfactants at interfaces and highlights the potential of optical tweezers for surfactant research. The development of this trap-and-track approach can have important implications for various applications, including drug delivery and nanomaterials. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) hybrid organic–inorganic perovskites (HOIPs) have attracted tremendous research interest due to their unique structure and promising applications. However, research on the design, synthesis and properties of this kind of metal-free crystalline material is still in the exploratory stage. Herein, two 3D perovskite molecules [1,4-3.2.2-dabcn]NH4Br3 (1) and [1,4-3.2.2-dabcn]NH4I3·0.5H2O (2) were obtained by reacting 1,4-diazabicyclo[3.2.2]nonane (1,4-3.2.2-dabcn) with NH4X (X = Br and I) in the corresponding concentrated halogen acids. The single X-ray diffraction results demonstrated that the inorganic framework structures in compounds 1 and 2 constructed with NH4Br and NH4I are completely different, caused by the radius of the bromide ion being smaller than that of the iodide ion. The 3D framework of compound 1 is constructed with a coplanar dimer [(NH4)2Br6]2− as the basic building unit, leading to the expanded 3D perovskite framework structure with a larger cavity to accommodate the 1,4-3.2.2-dabcn molecule. Nevertheless, compound 2 adopts a familiar 3D crystal framework structure with corner-sharing [(NH4)I6] octahedra, where the [1,4-3.2.2-dabcn] cations and water solvent molecule are confined in the cavities enclosed by the octahedra. Notably, both compounds exhibit reversible phase transition, dielectric anomaly and the second harmonic generation (SHG) effect. From the perspective of molecular design, this work is of great significance to guide the construction of new 3D metal-free perovskite molecular materials with reversible properties. [ABSTRACT FROM AUTHOR]

Product safety is important for medicines. For drugs on the market, it must be demonstrated that the levels of toxic contaminants are below the permitted limits. These impurities are used as reagents or are generated during synthesis. N-bromosuccinimide is used as a brominating agent in the synthesis of some active pharmaceutical ingredients. The determination of N-bromosuccinimide is difficult due to its high reactivity. In this work, a high-performance ion chromatographic method was developed for the determination of N-bromosuccinimide. The ion chromatographic measurement can be performed in two ways, one involves the assay of the resulting bromide ion and the other is via the assay of the 3-carbamoyl propanoic acid ion produced from the succinimide. Both acid ions were analyzed on an anion exchange column by gradient elution with potassium hydroxide eluent and detection was performed by a suppressed conductivity detector. During the method development, the results showed that the measurement of bromide ion was more selective than the measurement of 3-carbamoyl propanoic acid ion. Two different types of active pharmaceutical ingredients (API), i.e., prasugrel and favipiravir, were chosen to test the developed method and sample preparation. For both APIs, sample preparation was performed in a vial and consists of liquid–liquid extraction with an alkaline reagent. Finally, the anion exchange ion chromatography method was validated at the limit value level, and harmonized with the guidelines. For prasugrel, the quantification limits and the accuracy at the limit level are 7.2 ppm and 96.4%, while for favipiravir these are 7.5 ppm and 114.7%, respectively. [ABSTRACT FROM AUTHOR]

With the advancement of nuclear energy, the safe disposal of radioactive materials, especially nuclear waste containing iodine, has become a serious issue attracting attention. Thus, reported here is a general strategy for creating a cationic covalent organic framework (TAPT-COF-AB) containing a significant number of free bromide ions through post-synthesis modification of a hydroxy-functionalized COF (TAPT-COF-OH) and exploration of the ionic covalent organic frameworks (iCOFs) for iodine adsorption. Owing to TAPT-COF-AB retaining good crystallinity and large BET surface area, it exhibits excellent adsorption capacity for iodine with a maximum adsorption capacity of up to 5.05 g/g. The results indicate an increase of 1.44 g/g compared to TAPT-COF-OH (3.61 g/g) and maintained its high performance even after five cycles. Furthermore, the calculation of density functional theory (DFT) shows the significant chemical interaction between iodine and the material frameworks and supports the accuracy of the experiment. The results performed that including ionic groups increased the affinity between COFs and iodine, thereby enhancing the iodine adsorption properties. This work opens an avenue for constructing functional COFs for environmentally relevant critical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A tetracationic ionic with bromide anions ionic liquid has been developed. • Dual Brønsted acid sites and four bromide ion sites allowed the synthesis of DFF in excellent yield and selectivity. • The catalyst can be reused in three consecutive runs. • The procedure can be applied to large-scale DFF synthesis. A plausible solution to the current energy crisis is the development of cost-effective and inherently secure methods for accelerating the sustainable production of value-added compounds from biomass. In this study, we have developed a highly efficient catalytic system for the conversion of fructose into 2,5-diformylfuran (DFF) using tetracationic ionic liquids with dual Brønsted acid sites and four bromide ion sites. The presence of Brønsted acid sites promotes the production of 5-hydroxymethylfurfural (HMF), while the bromide anions react to form a DFF, which undergoes further transformation via the Kornblum mechanism. Under optimized conditions, a remarkable DFF yield of 99.6 % was attained in dimethyl sulfoxide (DMSO) at 140 °C for 6 h. Moreover, the catalyst exhibited excellent stability and reusability, indicating its potential for industrial application in the synthesis of DFF from fructose. With the help of this effort, Br- anion may be able to throw some light on the oxidation of HMF to DFF. Overall, this study highlights the promising application of tetracationic ionic liquid catalyst systems, showcasing the potential for the efficient utilization of renewable biomass resources and the synthesis of high-value-added compounds. [ABSTRACT FROM AUTHOR]

• Defect-free Cu bottom-up filling in TSVs is achieved using CTA+ and Br-. • Negative differential resistance (NDR) behavior is observed with CTA+ and Br-. • The effect of CTA+ and Br- on the passive-active transition is investigated. • CTA+ determines the location in TSVs where the passive-active transition occurs. • Br- enhances the suppression with CTA+, preventing void entrapment inside TSVs. Suppressing additives for Cu electrodeposition play a critical role in inducing bottom-up filling in micrometer-scale features such as through-silicon vias (TSVs). This study explores the adsorptive behaviors of cetyltrimethylammonium cation (CTA+) and bromide ion (Br-) and their application to defect-free TSV filling. Electrochemical analyses reveal that both CTA+ and Br- suppress Cu electrodeposition, with only CTA+ exhibiting negative differential resistance (NDR) behavior. The addition of Br- to CTA+ enhances the suppression effect while maintaining the NDR behavior of CTA+. TSV filling experiments demonstrate that the NDR behavior of the CTA+ and Br- combination induces the passive-active transition on the sidewalls of TSVs, which is essential for Cu bottom-up filling. The effects of CTA+ and Br- concentrations on the passive-active transition are also investigated, showing that CTA+ determines the height at which the passive-active transition occurs, while Br- enhances suppression to inhibit Cu growth on the sidewalls in the active region. Based on these behaviors, the optimal CTA+-Br- combination leads to successful bottom-up filling in TSVs. The mechanisms of TSV filling with CTA+ and Br- are suggested based on electrochemical analyses and gap-filling results. The active region at the TSV bottom, formed via selective breakdown of suppressing adsorbates, is filled while effectively inhibiting Cu deposition on the sidewalls, followed by filling the remaining portion of TSVs with vertical Cu growth. [Display omitted] [ABSTRACT FROM AUTHOR]

Plasma-activated seawater (PASW) presents a promising approach for marine fish preservation, yet its antimicrobial efficacy and mechanisms remain unclear. This study found that PASW exhibits superior bactericidal properties against the fish spoilage bacterium Shewanella putrefaciens compared to plasma-activated water (PAW), and increased effectiveness in preserving fish fillets. To clarify the mechanisms, a detailed investigation was conducted, including the generation of reactive oxygen/nitrogen species (ROS/RNS) and active halogen species in PASW, and their antimicrobial efficacy. Findings showed greater nitrite and hydrogen peroxide production in PASW relative to PAW, as well as the conversion of chloride/bromide ions into active species, which collectively enhanced PASW's antimicrobial activity. The synergistic action of ROS/RNS and active chlorine/bromine species in PASW promoted the generation of intracellular ROS, causing increased membrane damage, redox imbalance, and consequently higher bacterial mortality. This study enhances our understanding of PASW's antimicrobial effects and highlights its potential applications in the seafood industry. [Display omitted] • PASW has higher antimicrobial activity than plasma-activated water (PAW). • More hydrogen peroxide (H 2 O 2) and nitrite (NO 2 −) are formed in PASW than in PAW. • Chloride/bromide ions are activated to active chlorine/bromine species in PASW. • H 2 O 2 , NO 2 −, and active halogen species synergistically enhance PASW's antimicrobial activity. • PASW's bactericidal components significantly damage bacterial membrane and redox systems. [ABSTRACT FROM AUTHOR]