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The stability of ionic conducting membranes is a crucial concern for using as the electrolyte in electrochemical devices. Herein, aminated lignin (AL) is used as the cross-linker and free radical scavenger to enhance the properties of anion exchange membranes (AEMs) based on quaternized poly (terphenyl piperidinium-co-trifluoroacetophenone) (QPTPT). The prepared membranes achieve a hydroxide conductivity of 112 mS cm−1 and a proton conductivity of 210 mS cm−1 at 80 °C. The presence of AL obviously improves the resistance of the AEMs to the attack of both OH− ions and free radicals. A conductivity retention rate of about 80 % is achieved by the prepared membranes after soaking in 2 mol L−1 KOH solutions at 80 °C for 1500 h. Meanwhile, the retained tensile stress at break of these aged membranes is within the range of 26 to 37 MPa. The amphoteric water electrolytic cell using the proposed membrane as the diaphragm achieves a current density of 954 mA cm−2 under 2 V at 80 °C. This electrolytic cell can work stably at a current density of 100 mA cm−2 at 20 °C for 83 h with an initial energy consumption of 2.8 kWh m−3 for hydrogen production. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Tri-metal heterojunction catalyst was synthesized by sequential hydrothermal process. • FSW exhibited remarkable electron transfer efficiency and kinetic rate. • Synchronization of persulfate activation and photocatalysis by FSW/PMS/vis system. • DFT calculations confirmed the enhanced adsorption and charge density of FSW to PMS. • Nonbiological toxicity of intermediates indicated the environmental appropriateness of the system. The outstanding performance of advanced oxidation processes based on self-generated active species in the decomposition of antibiotics has attracted widespread attention. Herein, a novel heterojunction flower-shaped microsphere Iron-based Hydroxide/Tungstate Antimony Oxide (FSW) composed of nanosheets with synchronous persulfate activation and photocatalytic properties were proposed to achieve efficient degradation of sulfadiazine (SDZ) by enhanced active oxidation species. Constructed FSW/PMS/vis system realized the improved removal of SDZ at pH 2–6, with a degradation efficiency of 96.6 % in just 6 min (electron transfer efficiency, 6.19 × 10–4 A/cm2; kinetic rate, 2-ORR). Investigation of density functional theory demonstrated the superiority of FSW catalysts (Eads = -1.63 eV), indicating that FSW can not only enhance the adsorption of PMS but also activate PMS to generate a large number of free radical ions, realizing rapid carrier movement and effective charge transfer, which highlights the application prospects of the system in eliminating antibiotics in environmental water bodies. [ABSTRACT FROM AUTHOR]

A fast and effective technique is the need of the hour for the treatment of dye polluted wastewater to safeguard living beings and the environment. Photocatalysis treatment of dye contaminated wastewater has emerged to be an appealing approach. Here in the present report, novel nitrogen doped‑carbon dots (N-C-dots) are produced by simple pyrolysis approach at 300 °C for different time intervals of 1 h, 2 h and 3 h using garlic (Allium Sativum) for the degradation of crystal violet (CV) dye. The resulting N-C-dots have crystalline nature, nearly spherical with particle size ranging from 3.06 to 15.97 nm, and biocompatible. Also, these N-C-dots showed excellent capability as photocatalyst (0.06 g) by degrading 40 ppm of CV dye up to 99.13 % at pH = 5 under UV irradiations in just 80 min. The capture studies showed that superoxide ions and hydroxyl radicals are primary components in the photocatalytic degradation of CV dye. Furthermore, these N-C-dots exhibited the excellent reusability, stability and biocompatibility sequentially. [Display omitted] [ABSTRACT FROM AUTHOR]

Spiropyrans and spirooxazines (SP) are known to undergo photochromism to form merocyanines (MC). In this study, upon pulsed electron radiolysis of SP in organic solvents, we observed the transient absorption spectra of SP radical ions in the visible wavelength region. Based on first-order kinetics in the microsecond time domain, the absorption spectra changed to different ones, which were plausibly due to the radical ions of the corresponding MC. The reaction rates from SP radical ions to MC ones were determined. Using heats of formation for the radical ions of SP and MC evaluated with DFT calculations, the differences in heats of formation between the radical ions of SP and MC were determined to be exothermic. The reaction rate correlated with the difference in heat of formation, which depended on the parity of the radical ions. Time-dependent DFT calculations provided the SOMO surfaces of the radical ions of SP and MC. Comparing the SOMO with the LUMO, HOMO, and HOMO-1 surfaces of the neutral SP, we found that the attached electron locates on the LUMO upon one-electron reduction in SP, whereas the HOMO-1 of SP is involved in one-electron oxidation of SP rather than the HOMO. • Pulsed electron radiolysis of spiropyrane and spirooxazine (SP) was performed to obtain the radical ions. • The radical ions of SP were found to change to those of the corresponding merocyanines (MC). • Rates for the radiochromic reaction of SP were determined. • Differences in heats of formation for the radical ions rationalized the radiochromism of SP. [ABSTRACT FROM AUTHOR]

This work reports, improved photo catalytic performance of ZnO by band gap engineering via Eu doping (0.5–2.0 %). Single phase wurtzite structure of sol gel derived ZnO and Eu (0.5–2.0 %) doped ZnO are confirmed by XRD, FTIR and Raman spectra. Slight variation in structural parameter, FTIR stretching mode at 677 cm−1 and Raman E 2 peak position indicate substitution of Eu+3 in ZnO. Calculated band gap decreases [3.05-2.89] with Eu concentration due to generation of charge trap level. Dye degradation of MO improved in Eu doped ZnO as compare to ZnO. The catalytic effectiveness is clearly shown by significant breakdown of a commonly used MO dye (at a concentration of 120 mg l−1). ZnO: Eu 2 % has a remarkable clearance rate of 99.37 %, which is explained by pseudo-first-order kinetics. The increase in oxygen radical ion concentration due to presence of Eu 2 O 3 impurity phase in Eu 2 % doped ZnO supports MO degradation mechanism. [ABSTRACT FROM AUTHOR]

Although the research on self-healing waterborne polyurethane has been relatively in-depth, accomplishing rapid self-healing at room temperature along with superior mechanical properties remains a substantial challenge. Herein, a three cross-linking waterborne polyurethane (TeWPU–Zn-x) with triple dynamic bonds was prepared by adding ditellurium glycol, isophorone diamine, and trimethylolpropane to the backbone of the waterborne polyurethane, forming coordination bonds between carboxyl groups on the backbone of the waterborne polyurethane and zinc ions. Owing to the cooperative action of three distinct types of cross-linking and triple dynamic bonds, the film of TeWPU–Zn-3 exhibits outstanding mechanical features (the tensile strength, 40.58 MPa; the fracture toughness, 20.75 MJ m2; the elongation at break, 629.15 %) and a remarkable self-healing efficiency (89.43 % under a trace amount of ethanol induction and visible light irradiation at room temperature for a duration of 2 h) simultaneously, demonstrating an exceptional balance between mechanical robustness and rapid room temperature self-healing, whose two characteristics outperforms those of the self-healing waterborne polyurethane reported so far. After reprocessing, the TeWPU–Zn-3 film cut into particles is basically restored to its original state and the reprocessing film can easily weigh 5 kg dumbbells. Moreover, due to the incorporation of zinc ions and ditellurium bonds, TeWPU–Zn-3 film is endowed with good antibacterial properties (S. aureus , 99.3 %; E. coli , 97.5 %). Importantly, when used as leather coating, TeWPU–Zn-3 also shows a protective self-healing ability on the leather. In summary, this work provides a promising avenue for the creation of waterborne polyurethane distinguished by their superior mechanical attributes, rapid room temperature self-healing, reprocess ability, and antibacterial properties. [Display omitted] • A novel strategy fabricates a three cross-linking WPU with triple dynamic bonds. • The strategy achieves mechanical robustness and rapid room temperature self-healing. • The presence of triple dynamic bonds enables the reprocessing of the WPU films. • The WPU film with zinc ions and tellurium radicals almost completely kills bacteria. • The WPU emulsion as a leather coating can repair itself under mild conditions. [ABSTRACT FROM AUTHOR]

In this study, antioxidant nanofiber-based food packaging material composed of polylactic acid (PLA) and mangiferin (MG) was produced to reduce food spoilage. To this end, MG was extracted from Mangifera indica and chemically characterized. In vitro assays for scavenging several radical ions showed excellent antioxidant properties of MG. Thereafter, MG was blended with PLA to form nanofibers (PLA-MG) using electrospinning. The Field Emission-Scanning Electron Microscopy (FE-SEM) images of the prepared nanofibers displayed defect-free homogeneous morphology with an average fiber diameter of 176.89 ± 61.97 nm. Fabricated nanofibers were physico-chemically characterized. From chromatography, mangiferin content in the PLA-MG fiber was found to be 40.55 ± 3.7 μg/mg of fiber. Contact angle measurements of the fabricated nanofibers showed the hydrophobic nature of PLA-MG nanofibers. PLA-MG nanofibers demonstrated a significantly higher antioxidant activity compared to PLA nanofibers (**** p < 0.0001), as evidenced by their superior performance in DPPH, ABTS, and FRAP assays. Specifically, PLA-MG nanofibers exhibited 3676 ± 3.46 mg/100 g vitamin C equivalents in antioxidant activity (VCEAC) and 1866 ± 2.12 VCEAC in ABTS and DPPH radical scavenging assays respectively. Further, apples wrapped with PLA-MG nanofibers showed that the browning of the fruit decreased when compared with controls. The MTT assay and live-dead assay indicated that the fabricated nanofibers were cytocompatible with L929 fibroblasts. The results showed that the fabricated PLA-MG nanofibers can be an effective non-toxic food packaging material to increase the shelf-life of the food. Finally, PLA-MG nanofiber-coated food container production was demonstrated to be commercialized for the effective transportation of food. [Display omitted] • Mangiferin extracted for fabrication of antioxidative nanofibers. • Mangiferin containing nanofibers characterized. • Cyto-compatibility of nanofibers confirmed. • Prevention of browning of apples achieved with nanofibers. • Possible application as food packaging material. [ABSTRACT FROM AUTHOR]

Light hydrocarbons (C 1 -C 9) offer a specific opportunity to study petroleum generation mechanisms. However, a significant amount of light hydrocarbons evaporate during sample collection, preservation, and preparation. This study aims to identify the origin of light hydrocarbons preserved in the closed pores of Jurassic shale strata from the Sichuan Basin where evaporative losses have been minimized. Twenty-one samples of various maturity levels and lithofacies were investigated using a new approach based on online decrepitation-gas chromatography. Light hydrocarbons were released from the closed pores of finely stratified mudstone, limestone, and siltstone. Among these, gaseous hydrocarbons in the C 1 -C 5 range were utilized to discriminate between petroleum generated by two opposing reactions, i.e., free radical and carbenium ion cracking. Accordingly, in situ petroleum can be divided into three types. (1) Free radical cracking type: a predominance of methane and straight-chain alkanes in the gaseous hydrocarbon range; (2) Carbenium ion cracking type: a deficiency of methane and straight-chain alkanes in gaseous hydrocarbons; (3) Mixed cracking type: their gaseous hydrocarbons exhibit intermediate compositions between those of free radical and carbenium ion cracking types. Differences in the chemical composition of the gaseous hydrocarbons, which can be used to discriminate between the two generation mechanisms, were further supported by variations in the mineral composition, e.g., calcite and mixed-layer clay minerals are characteristic of free radical reaction and carbenium ion reaction, respectively. The present classification diagrams for gaseous hydrocarbons are based on the Jurassic shale strata of the Sichuan Basin. This novel approach for determining the whole range of hydrocarbons from closed pores shows promising prospects for deciphering the origin of light hydrocarbons and thus may be extended to other regions of interest. • A novel approach is proposed based on online decrepitation-gas chromatography for obtaining hydrocarbons in closed pores. • The grain density and nitrogen adsorption results of various particle sizes revealed the presence of closed pores in the strata from the Fuxing area. • The hydrocarbons from closed pores can be utilized to discriminate the source of organic matter and the petroleum generated by two generation mechanisms (free radical cracking and carbenium ion cracking) in the Fuxing area. [ABSTRACT FROM AUTHOR]

Explosion-proof electrical equipment must be tested with the spark test apparatus (STA). This discharge was important for electrical explosion-proof safety. This study aimed to investigate the effect of field emission on the contact spark of the STA. Results show that the primary discharge modes were field emission and electron impact ionization. The gap width was estimated to be 6–8 μm. The distribution of the ions and radicals were revealed under the different field emissions. The impact of radicals on ignition was also discussed. [Display omitted] • GC was used to analyse the gas composition, so as to ascertain whether methane participated in the discharge process. • The gap distances at which contact spark discharges of STA can occur were estimated by analysing the discharge mechanism. • A one-dimensional fluid model was used to discuss the impact of FE on discharge and particle generation. • A zero-dimensional model was constructed to discuss the effect of radicals on methane ignition. [ABSTRACT FROM AUTHOR]

[Display omitted] • Molecular engineering strategies for improving NAORFBs cycling performance. • The effect of the supporting electrolyte on NAORFB cycle stability is reviewed. • Using ion-exchange membranes and bipolar electroactive molecules reduces crossover. • Major challenges to the commercialization of NAORFBs are highlighted. • The prospects for robust NAORFB development are discussed. Redox flow batteries (RFBs) have attracted researchers due to their decoupled nature of energy and power modulations, suitability for large-scale stationary energy storage, and integration of renewable intermittent energy sources such as solar and wind power. Water's narrow electrochemical stability window limits the energy density of aqueous redox flow batteries. Thus, a shift to non-aqueous organic redox flow batteries (NAORFBs) is necessary to achieve high energy density while benefiting from organic solvents' expansive electrochemical stability windows. Nonetheless, the degradation and crossover of organic electroactive materials cause rapid capacity loss in NAORFBs. To improve the cycling stability of NAORFBs, molecular engineering is required to enhance the stability of redox-active species, particularly charged species, and the solubility of redox-active species. An appropriate ion-selective membrane that mitigates crossover by selectively allowing the passage of ions of supporting salts needs to be developed. This review discusses molecular design strategies that may improve radical ion stability, increase the solubility of redox-active species, and reduce redox-active species crossover and the selection of appropriate supporting electrolytes and separators/membranes for the overall enhancement of the cycle life and performance. [ABSTRACT FROM AUTHOR]

• The charge carriers of the mono- and bis-phenothiazinyl-substituted compounds have been investigated using EPR and UV-vis-NIR spectroelectrochemistry. • In bis-phenothiazinyl-substituted compounds with thiophene linker, the charge is predominantly localized on the thiophene moiety. • For the compounds containing central phenyl rings in the thiophene linker, the oxidation is phenothiazine-based. The charged species of 10 H -phenothiazinyl-substituted thiophenes have been investigated by means of combined in situ electron paramagnetic resonance (EPR) and ultraviolet−visible−near infrared (UV−Vis−NIR) spectroelectrochemistry. The molecular structure of the compounds under study contains one or two phenothiazine moieties, which are connected by various thiophene linkers in the case of the latter. The optical and magnetic properties of the radical cations and dications as well as the information about their stability were provided. The impact of the linker structure on charge localization (on phenothiazine or thiophene moiety) for bis-phenothiazinyl-substituted compounds was investigated. The experimental data were supported by density functional theory (DFT) calculations, which predicted the favored charged structures of the studied compounds. [Display omitted] [ABSTRACT FROM AUTHOR]

• Tetrathiafulvalene demonstrates versatility in molecular electronics. • Experimental and computational methods integrate for a redox-active hybrid. • Crystal structure analysis exposes a deformed pyramid in Copper (II) complex. • Noteworthy charge transfer in electronic properties hints at photoelectron conversion suitability. • Reactivity analysis pinpoints potential attack sites, highlighting sulfur atom reactivity. This paper presents a comprehensive study that combines experimental techniques and Density Functional Theory (DFT) to investigate a newly synthesized mixed-ligand complex, [Cu(hfac) 2 (Me 3 TTF-CH=CH-Pyr)] (where hfac is hexafluoroacetylacetonate), and a novel mixed-valence radical ion salt (Me 3 TTF-CH=CH-Pyr) 2 (PF 6) 3. Both are constructed using ligands derived from the tetrathiafulvalene (TTF) donor molecule. These materials are meticulously characterized through single-crystal X-ray diffraction analysis. The complex crystallizes in the monoclinic system, specifically in the C2/c space group, with the following lattice parameters: a = 24.583(2) Å, b = 21.613(2) Å, c = 14.2066(13) Å, β = 99.789(5)°, and a volume of V = 7438.3(12) Å3. It exhibits five-coordinate behavior, forming a slightly distorted pyramid with a square base. The paper also provides a detailed account of the crystal structures and reports spectroscopic study results. Electrochemical behavior is explored through cyclic voltammetry in CH 2 Cl 2 as the solvent. Additionally, the reactivity of these compounds is predicted using various theoretical tools, such as Local and Global reactivity descriptors, Hirshfeld charge analyses, and Molecular Electrostatic Potential. To elucidate charge transfer processes, Time-Dependent Density Functional Theory is utilized. Various types of interactions are analyzed through the Quantum Theory of Atoms in Molecules and Non-Covalent Interaction analyses. Finally, conductivity is estimated using frontier molecular orbitals (FMO) and gap energies as crucial parameters. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Peroxyoxalate chemiluminescence in aqueous medium is several orders of magnitude less efficient than in anhydrous aprotic organic solvents. • However, water addition of up to 0.7 mol/L to an aprotic organic medium results in a significant increase of singlet excitation quantum yields. • Contrarily, higher water concentrations result in a drastic quantum yield decrease, which is not only due to oxalic ester hydrolysis. • Photophysical studies with several chemiluminescence activators confirm the mechanism of the chemiexcitation step in partially aqueous media. Chemiluminescence transformations are widely utilized in analytical and bioanalytical applications. Specifically, the peroxyoxalate system can be employed for sensitive quantification of a wide variety of analytes. Under anhydrous conditions, the peroxyoxalate reaction shows extremely high emission quantum yields, comparable to highly efficient bioluminescence systems. However, in aqueous media, important for bioanalytical applications, the emission efficiency suffers a significant decrease of several orders of magnitudes, although the reason for this loss in efficiency is unknown up to now. In the present work, we show the results of a detailed photophysical study on the effect of water on the chemiexcitation efficiency of the peroxyoxalate reaction using bis(2,4-dinitrophenyl) oxalate as reagent and imidazole as base catalyst in the presence of different chemiluminescence activators. It is shown that in 1,2-dimethoxyethane/water mixtures (DME:H 2 O), singlet quantum yields increase with increasing the water concentrations up to 0.7 mol/L, followed by a steady decrease at higher water concentrations. The decrease in quantum yields is not predominantly due to concurrent ester hydrolysis, as quantum yields could be corrected for this side reaction. This indicates that the quantum yield decrease is due to the diminished chemiexcitation efficiency in the presence of water. Using different activators, it is shown that chemiexcitation occurs via electron transfer and electron back-transfer steps between a high-energy intermediate and the activator. Additionally, its efficiency is governed by the energetics of the electron back-transfer step, in agreement with the Chemically Initiated Electron Exchange Luminescence (CIEEL) mechanism, also in partially aqueous environment. Lower excitation efficiency in aqueous media may be due to formation of solvent-separated radical ion pairs, inhibiting chemiexcitation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Redox reactions in groundwater can help define earthquake chemical precursors. • H 2 O 2 and ∙OH radicals play key roles in generating the chemical precursors. • Advanced oxidation contributes greatly to the oxidation of organic compounds. • Behavioral changes in organisms before earthquake can help validate precursors. • Earthquake chemical precursors could be supportive to developing early warning system. To minimize the loss of life caused by earthquakes, it is crucial to have early warning tools that provide sufficient warning time. Although various methods are available, their accuracy is uncertain. This review explores alternative indicators related to hydrogeochemical anomalies that appear before earthquakes, which could potentially offer earlier warnings. It presents a theoretical basis for ionic and molecular changes initiated by the generation of hydroxyl radicals (•OH) and hydrogen peroxide (H 2 O 2) in groundwater before an earthquake. The review analyses 32 earthquake events by measuring ionic anomalies through standard reduction potential. The study also identifies significant pre-seismic erosional activity in minerals exposed to hydrogen peroxide. Additionally, the oxidation of organic compounds is shown to predict notable geochemical changes. The changes in the groundwater chemistry can also be validated by examining simultaneous microbial/ zooplankton responses. The findings suggest that the ionic, mineral, organic, and microbiological changes triggered by hydroxyl radicals and hydrogen peroxide could serve as a multi-parametric earthquake early-warning system. Implementation of such a system could improve the accuracy and timeliness of earthquake warning systems potentially reducing the associated risks and damages. [ABSTRACT FROM AUTHOR]

[Display omitted] • Intense ECL from Ir(ppy) 3 was realized by using the radical anion of benzonitrile. • The ECL intensity of the mixed system was ∼ 250 times greater than that of the single system. • The ECL intensity increased by ∼ 90 times with the radical cation of thianthrene. • The mechanism of enhancing the ECL with several radical cations and anions is discussed. The electrogenerated chemiluminescence (ECL) of 0.2 mM tris(2-phenylpyridinato)iridium(III) (Ir(ppy) 3) in acetonitrile with a potential step method was dramatically enhanced by the electrochemically generated radical cation of 10-methylphenothiazine (MePT), thianthrene (TH), and dibenzo-1,4-dioxin (DD) or the radical anion of benzophenone (BP) and benzonitrile (BN). In the case of using the radical cation of phenothiazine (PT), no ECL was seen. Among the binary systems containing 0.2 mM Ir(ppy) 3 and 10 mM parent molecule of the radical ions, intense annihilation ECL of Ir(ppy) 3 was observed from a solution containing BN; the ECL intensity was about 250 times greater than that of the single system of 0.2 mM Ir(ppy) 3. Among the cases using the radical cations, the ECL intensity with TH was the largest (about 90 times higher than that of the single system). The mechanism for enhancing the ECL is discussed based on the redox potential, energy level of the lowest triplet excited (T 1) state, and electron-donating and −accepting characteristics. The electron transfer reaction between the reduced form of Ir(ppy) 3 (Ir(ppy) 3 •−) and the radical cations can produce the T 1 state of Ir(ppy) 3 (3Ir(ppy) 3 *) and that of MePT, TH, and DD, whereas the electron transfer reaction between the oxidized form of Ir(ppy) 3 (Ir(ppy) 3 •+) and the radical anions can produce 3Ir(ppy) 3 * but not the T 1 state of BN or BP. The lower ECL intensity using the radical cations relative to that of using BN suggests that the triplet energy transfer from the parent molecule of the radical cations to Ir(ppy) 3 is not efficient. It is also shown that the homogeneous electron transfer reaction between Ir(ppy) 3 and the electrochemically generated radical cation of TH and radical anion of BN to produce Ir(ppy) 3 •+ and Ir(ppy) 3 •−, respectively, which facilitates an ion annihilation reaction between Ir(ppy) 3 •− and Ir(ppy) 3 •+, is also responsible for the intense ECL. [ABSTRACT FROM AUTHOR]

• Uranium can be removed efficiently in air under natural solar with addition of benzyl alcohol without photocatalyst. • The residual concentration of U(VI) after photo-autocatalysis is lower than the emission standard in GB 23727-2020. • The intermediate [UO 2 +, Ph·CHOH] caused by U(VI) and benzyl alcohol can improve the photosynthesis of H 2 O 2. • The removal rate of simulated uranium-containing effluent could get to 99.08 %, suggesting great application potential. Photocatalysis, one of the environment-friendly and efficient technology, showed application prospects on uranium removal and recovery in spite of the expensive photocatalysts. Herein, we reported a novel strategy induced by benzyl alcohol for photo-autocatalytic removal and recovery of uranium, which achieved excellent removal rate and avoided the dependence on photocatalysts. The results showed that, in slightly acidic environments, the uranium removal rate could achieve over 99 % under air within an hour illumination via the redox reaction of radical ion pair [UO 2 +, Ph·CHOH], which can be produced by the photoactivation of benzyl alcohol for the active benzylic C(sp3) − H bonds. At the same time, benzyl alcohol was selectively oxidized to benzaldehyde, an important industrial feed stock of significance in fine and chemical industries. Moreover, uranium could be removed to 186 ppb within 4 h of illumination, which was up to the emission standard proposed in GB 23727–2020. This strategy exhibited excellent removal performance upon solar illumination and recovered uranium with 99.08 % removal rate in the existence of heteroions, which indicated that our strategy has important application potential. [ABSTRACT FROM AUTHOR]

We present a comprehensive review of the photochemical and electrochemical methodologies employed in the α-C–H functionalization of tertiary amines. The discussion starts with an introduction to α-C–H functionalization strategies, emphasizing the generation of radical species. The iminium ion and α-aminoalkyl radical are identified as key intermediates interacting with various organic functional groups. The review is divided into two main sections: photocatalytic and electrocatalytic α-C–H functionalization. In the photocatalytic section, we classify the functionalization into photocatalyst-mediated and photocatalyst-free approaches. Photocatalyst-mediated functionalization is further categorized into four mechanisms: Nucleophilic substitution, Transition-metal complexing, Giese-type reaction, and Radical-radical cross-coupling. Photocatalyst-free functionalization focuses on the direct excitation of the substrate and the EDA complex pathways, with particular emphasis on the latter. The electrocatalytic section explores both direct and indirect electrolysis techniques, highlighting the role of redox mediators in the indirect approach. Each section critically analyzes recent research examples from the past five years. This review aims to elucidate the current state of α-C–H functionalization research and suggest promising directions for future investigations. [Display omitted] [ABSTRACT FROM AUTHOR]

Organic sulfur compounds (S-markers) such as benzothiophene (BT), dibenzothiophene (DBT), and benzonaphtothiophene (BNT) have been used for depositional paleoenvironment interpretations. In this study, the broader range of S-markers was semi-quantified by Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FTICR-MS) using atmospheric pressure photoionization in positive ion mode (APPI-P) for the interpretation of the depositional paleoenvironment and lithology in Amaral Machado's outcrop, Irati Formation, Paraná Basin for the first time. The variations in chemical composition, aromaticity as well as alkylation degree of the monosulfur compounds (S 1) and hydrocarbons (HC) classes (radical and protonated ions) analyzed in APPI-P were discussed in detail. The S-markers were semi-quantified using the internal standard DBT-d 8. The results from both S 1 and HC showed a clear distinction in the depositional paleoenvironment of the organic matter (OM) present in the evaluated samples. The S-markers interpretations were confirmed by classical biomarkers (regular steranes C 29 /C 27 , tetracyclic polyprenoids TPP/C 27 , diasteranes DIA 27 , steranes/17α-hopanes, gammacerane/C 30 , and pristane/phytane). The similarity in depth profiles using concentrations and peak intensities indicated that the ionization of major compound classes from extracts analyzed in APPI-P mode is not compromised by ion suppression. The double bond equivalent (DBE) distribution of S 1 and HC, together with the DBT/Phen ratio, provided valuable insights into the type and source of OM contributing to the reconstruction of the depositional paleoenvironment. S-markers semi-quantification was efficient in characterizing depositional paleoenvironment and allowed evaluation of different proxies of the outcrops. The base of the Amaral Machado outcrop presents an anoxic redox condition, typically hypersaline and abundant in S 1. The middle of the outcrop shows a strong marine influence with a contribution from terrestrial OM. Towards the top of the outcrop, belonging to the Serra Alta Formation, the environment is oxidizing with low concentrations of sulfur and typically terrigenous. • Evaluation from Paleoenvironment in Irati Formation, Amaral Machado outcrop by S-markers. • Semi-quantification of organic sulfur compounds and HC class by FTICR-MS. • Paleoenvironments are distinguished by molecular composition. • S-Marker C 40 proved to be a good paleoenvironment indicator. [ABSTRACT FROM AUTHOR]

The degradation of 8 structurally diverse pharmaceuticals and personal care products (PPCPs) by UV/chlorine and the effects of Cl- and SO 4 2- were systematically investigated. The 8 PPCPs are divided into 2 groups based on their stability under UV light. This is the first time the kinetic degradation of the 8 PPCPs in the presence of Cl- and SO 4 2- have been intensively evaluated. The results showed that the high degradation rate of the PPCPs is attributed to their second-order rate constants towards radicals (i.e., •OH, and reactive chlorine species (RCS)). 0–500 mM Cl- enhanced k PPCPs , while this range of SO 4 2- inhibited most of them (except in the case of ciprofloxacin (CIP)). An overview of the effect of 0–200 mM Cl-/SO 4 2- on the degradation of micropollutants by different UV-based advanced oxidation processes (UV-AOPs) in previous studies indicates that Cl-/SO 4 2- can cause varying effects on the degradation rate of pollutants (i.e., "increase", "decrease", or "no effect"), depending on the type of pollutant and the process. Cl-/SO 4 2- did not change the trend of pH influence on the PPCPs degradation rates by UV/chlorine. Acidic and neutral conditions were favorable to the degradation of the PPCPs in all cases. Under three operating conditions (i.e., the control process, 500 mM Cl- and SO 4 2-), [•OH]ss decreased considerably, but [Cl•]ss or ([Cl•]ss + [SO 4 •-]ss) slightly fluctuated when the pH was increased from 2.5 to 10.5. The synergistic effect of seawater and Cl-/SO 4 2- significantly improved some k PPCPs , thereby, decreasing energy consumption. [Display omitted] • Kinetic degradation of eight PPCPs were investigated in UV/chlorine. • The degradation of PPCPs can be divided into two groups based on UV and seawater effects. • 0–500 mM Cl- can enhance k PPCPs , while this range of SO 4 2- inhibited them. • pH from 2.5 to 10.5 reduced [•OH]ss but had negligible effect towards [Cl•]ss or ([Cl•]ss + [SO 4 •-]ss). • The synergy effect of seawater and Cl-/SO 4 2- can significantly improve some k PPCPs. [ABSTRACT FROM AUTHOR]

• A strategy to enhance charge separated state lifetimes in compact dyads is reported. • Lifetime enhancement is nearly 1000 times. • Long lifetime is confirmed through secondary electron transfer experiments. • Long lifetime was attributed to low D-A electronic coupling. • The low electronic coupling is due to orthogonal orientation of D and A. Design of compact donor-acceptor dyads that can exhibit charge separated (CS) state lifetimes extending to the microsecond time domain remains a major challenge even today. A simple but effective design strategy that can lead to long CS state lifetimes, in at least a few compact dyads, is still elusive. Herein we propose that use of adamantane (AD) as bridge can enhance CS state lifetimes in small molecule donor-acceptor dyads. This paper reports AD-bridged dyads, AN-AD-NB and PY-AD-NB, wherein the anthracene (or pyrene) donor and nitrobenzene acceptor are attached to bridgehead positions of AD. The singlet CS states generated upon irradiation were long-lived (lifetimes >1 μs) and decayed to the ground and local triplet states, simultaneously. Electron transfer reactions of the CS state with secondary donor and acceptor established that the CS state is sufficiently long-lived to participate in intermolecular reactions. X-ray crystal structure of the AN-AD-NB dyad reveals that the donor and acceptor are orthogonally oriented, which reduces the donor-acceptor interaction, and thereby the charge recombination rate, significantly. By analysing the X-ray structure, we predict that all adamantane-bridged compact dyads will have orthogonal donor-acceptor orientation and exhibit long-lived CS states. We also report studies with bisadamantyl-substituted dyads and the results confirmed that the local triplets are formed from the CS state through hyperfine interaction. Based on our work we propose that the hyperfine interaction, which is not expected to occur in compact dyads because of the short donor-acceptor separation, can indeed occur if the CS state is sufficiently long-lived. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous nanofiber membrane gives gel electrolyte excellent liquid absorption rate and ultra-high ionic conductivity, • The dissociation and transport of lithium ions favored by NO 3 − anions, • Nanofiber membranes facilitate the interfacial stability and cycling efficiency. A nanofiber gel electrolytes with excellent physical properties, electrochemical properties, and cycle life based on poly(vinylidene fluoride)-hexafluoropropylene copolymer modified by magnesium–aluminum bilayered nanosheets (MgAl-LDs) intercalated with different acidic roots ions is prepared by electrostatic spinning. The electrolytes exhibit the best elongation at break of 166 % and tensile strength of 6.59 MPa, and the electrochemical windows are all higher than 5 V. Meanwhile, the ionic conductivity number of nano-GPE intercalated with CO 3 2–, ClO 4 −, and NO 3 – reach 5.55*10−3 S/cm, 5.04*10−3 S/cm, and 6.93*10−3 S/cm, respectively. The Li//Li symmetric battery can be stably cycled for more than 1000 h at 1 mA/cm2 with an overpotential of less than 50 mV. The LiFePO 4 // Li batteries assembled with nano-GPE modified by MgAl-LDs (s = NO 3 –) show better 0.1-2C multiplicity performance than CO 3 2– and ClO 4 −, accompanied by an optimal discharge capacity of up to 155 mAhg−1 at 0.1C as well as a high reversible capacity of 135 mAhg−1 and a capacity retention rate of 90 % after 100 cycles at 0.5C. In addition, the results of polarization, X-ray photoelectron spectroscopy (XPS), Computed Tomography (CT), and scanning electron microscope (SEM) tests show that a stable SEI film is formed between nano-GPE and Li anode. [ABSTRACT FROM AUTHOR]

In hydrothermal fluids, disulfur (S 2 •−) and trisulfur (S 3 •−) radical anions have been observed to coexist with the major hydrogen sulfide and sulfate species. These radical ions have potentially important effects on the solubility, transport and fractionation of metals and sulfur, with consequences for ore deposit formation and, more generally, for geochemical cycles of metals and volatiles. It is therefore essential to know the intrinsic isotopic properties of these important sulfur species in order to use sulfur isotopes for tracing different geological processes. Here, the theoretical equilibrium isotopic properties of the disulfur and trisulfur radical ions are computed and compared to the hydrogen sulfide (H 2 S) and sulfate ion (SO 4 2−), using, for the first time, a first-principles molecular dynamics (MD) approach. The isotopic properties are calculated directly from molecular dynamics trajectories using the vibrational density of states and the atomic kinetic energy, and then compared to the more established method based on sampling of several snapshots. This comparison allowed us to validate the new modelling method and to assess its advantages and limitations. The predicted equilibrium isotope fractionation in terms of 34S/32S between S 2 •− and S 3 •− is small, i.e. <1‰, with a slight enrichment in the heavier isotope for S 3 •−, over the temperature range 200–500 °C. Both radical ions are slightly depleted in the heavier isotope, by 1 to 2‰, relative to aqueous H 2 S. Our results help tuning sulfur isotope fractionation models used for tracing the origin and evolution of hydrothermal fluids. Our method opens large perspectives for using the rapidly growing body of MD simulation data in geosciences on structure and stability of aqueous complexes to assess in parallel element isotope fractionations from MD-generated trajectories. • S isotope fractionation among SO 4 2−, H 2 S, S 3 •− and S 2 •− in hydrothermal fluids. • Direct quantification of isotopic properties from molecular dynamics trajectories. • Assessing advantages and limitations of the novel molecular dynamics (MD) approach. • Perspectives opened by the MD method for predicting element isotope fractionations. [ABSTRACT FROM AUTHOR]

[Display omitted] • ED was coupled with AC for enhancing chlorine-resistant bacteria inactivation. • ED/AC had synergistic effects on chlorine-resistant/sensitive bacteria inactivation. • ED/AC had ∼ 2.5 times lower energy consumption for cell inactivation than AC alone. • EP/AC prompted the formation of neutral HClO molecules and free chlorine radicals. • ED/AC enabled oxidative damage of cell structures for bacterial inactivation. The widespread use of chlorination prompts the selection of chlorine-resistant bacteria in drinking water, posing a great threat to public health. Herein, according to sequential electrochemical oxidation/reduction (Ox/Red) processes with a flow-through mode, electrochemical devices (ED) with sequential Ox-Red, Red-Ox and Ox-Red-Ox processes were coupled with chlorination (AC) to evaluate their synergistic effects and mechanisms for inactivation of chlorine-resistant bacteria in drinking water. ED/AC enabled ∼ 3.0 log of synergistic effect and ∼ 2.5 times lower energy consumption for inactivation of various chlorine-sensitive/-resistant bacteria and gram-positive/-negative bacteria in DI and tap waters. Especially, ED/AC with Ox-Red-Ox device exhibited the best disinfection performance with achieving over 6.7 log inactivation of Bacillus cereus at 4.0 V and 0.5 mg/L-Cl 2 as compared with ED alone (∼1.25 log) and AC (∼2.67 log) disinfection. The electrochemical oxidation on Ti 4 O 7 -based anode promoted the generation of free chlorine radicals and H+ ions, which was accompanied with the formation of neutral HClO molecules. Characterizations of SEM and flow cytometer suggested that oxidative species of neutral HClO molecules and free chlorine radicals enhanced the bacterial inactivation via severe damages of cell structures. This work provided a promising strategy via coupling electrochemical oxidation and chlorination for eliminating chlorine-resistant bacteria in drinking water. [ABSTRACT FROM AUTHOR]

• The enhancement of CO 3 2− and Li+/K+ ions on Na 4 SiO 4 were stronger than other ions. • The cyclic capacity of Na 4 SiO 4 was enhanced about 40.0% after the Li 2 CO 3 doping. • CO 2 adsorbed on oxysalts modified Na 4 SiO 4 surfaces were studied by DFT method. • The theoretical calculation results accurately fitted with the experimental values. • The effects of water vapor on Na 4 SiO 4 and Na 4 SiO 4 -K 2 CO 3 were firstly simulated. Eutectic doping has been considered as one of the most efficient ways to modify the Na 4 SiO 4 -based CO 2 sorbent. Nevertheless, the effects of different acid radical ions and alkali metal cations of the oxysalts on the CO 2 capture performances of Na 4 SiO 4 have never been explored. In this study, Na 4 SiO 4 -based CO 2 sorbents were prepared using four kinds of oxysalts as the dopants. The effects of acid radical ions/alkali metal cations, doping ratios and sorption/desorption temperatures on the CO 2 capture performances of sorbents were investigated. The results showed that the promotion effects of CO 3 2− and Li+/K+ ions were stronger than others, the maximum CO 2 sorption capacity of Na 4 SiO 4 -30Li 2 CO 3 and Na 4 SiO 4 -30K 2 CO 3 at 700 °C reached 20.6 wt% and 19.5 wt%, respectively. The cyclic sorption capacity of Na 4 SiO 4 -30Li 2 CO 3 was 8.5 wt%, which was 40.0% higher than that of Na 4 SiO 4. Further, the oxysalt dopants could enhance the CO 2 adsorption energy on the Na 4 SiO 4 surfaces and reduce the energy level of the systems using density functional theory calculation, which were consistent with the experimental values. Finally, the effects of water vapor on the sorption of Na 4 SiO 4 and Na 4 SiO 4 -K 2 CO 3 were simulated, which could enhance the activity of O atoms on sorbent surfaces and promote rapid carbonization during the sorption progress. Thus, Na 4 SiO 4 doped with oxysalts exhibit promising potential for high-temperature CO 2 capture application. [ABSTRACT FROM AUTHOR]

Inorganic polysulfur compounds (polysulfides, S x 2 - ; polysulfur radical ions, S x · - ; thiosulfate, S 2 O 3 2 - ; polythionate, S x O 6 2 - ; elemental sulfur, e.g. S 8 ) participate in numerous geochemical processes related to the sulfur cycle. These include authigenic pyrite formation in sediments undergoing early stages of diagenesis, reactions associated with magmatic-hydrothermal processes, and numerous other aquatic sulfur redox processes (e.g., pyrite and sulfide oxidation). Sulfur isotope fractionations among many of these and associated compounds (e.g., H 2 S, HSO 4 - ) are either unknown or unconstrained over wide ranges of temperatures. We present theoretical estimates of equilibrium sulfur isotope fractionation factors among aqueous polysulfur compounds (including select polysulfides, polysulfur radical anions, and polythionates) and select aqueous sulfide and sulfate compounds that correspond to all three stable isotope ratios of sulfur ( 33 S/ 32 S, 34 S/ 32 S, 36 S/ 32 S). Our estimates are based on electronic structure calculations performed at the B3LYP/6–31+G(d,p) level of theory and basis set implemented in concert with an explicit solvation model whereby molecules are encapsulated in water clusters of varying size (30–52 H 2 O) to simulate the aqueous solvation environment. These calculations yield relatively small magnitude fractionation factors between aqueous polysulfides, polysulfur radicals, and reduced sulfur moieties in polythionates relative to the aqueous sulfide compounds but reveal numerous crossovers that result in non-intuitive temperature dependencies. Our predictions of 34 S/ 32 S-based fractionation factors among aqueous sulfur compounds generally agree with previous experimental constraints where available within estimated uncertainties (e.g., HSO 4 - / H 2 S (aq) , H 2 S (aq) / HS - , HSO 4 - / S 0 , H 2 S (aq) / S 0 ). We use our calculations to explore equilibrium isotope fractionations among polysulfur and sulfide compounds that are precursors to authigenic pyrite in the framework of established mechanisms (e.g., the polysulfide mechanism). We examine possible explanations for why pyrite formation may be associated with relatively small isotope fractionation with respect to precursor aqueous sulfur compounds. We additionally use our theoretical calculations to constrain multiple sulfur isotope ( 33 S / 32 S , 34 S/ 32 S, 36 S/ 32 S) mass balance models associated with the abiotic hydrolytic disproportionation of intermediate sulfur compounds ( SO 2 , S 8 , S 3 · - ) relevant to hydrothermal-magmatic-volcanic systems in order to illustrate the potential for subtle but potentially resolvable effects expressed in values of Δ 33 S and Δ 36 S associated with these processes. We apply a SO 2 disproportionation mass balance model based on previous work but newly constrained by our theoretical calculations to (hyper-) acid crater lakes associated with active volcanoes, and newly highlight the potential for the utility of multiple sulfur isotope analyses in volcanic gas monitoring and constraining sulfur cycling processes in such systems. [ABSTRACT FROM AUTHOR]

Copper indium sulfide (CuInS 2) and CuInS 2 modified with different percentages of CdS (10% CdS@CuInS 2 , 20% CdS@CuInS 2 , and 30% CdS@CuInS 2) were successfully synthesized, as confirmed by structural, optical, and morphological characterization. The photocatalytic performance of the CuInS 2 and CdS@CuInS 2 composites was evaluated by degrading brilliant green (BG) dye and converting 4-nitrophenol under visible light irradiation. Amongst the synthesized photocatalysts, 30% CdS@CuInS 2 exhibited the highest photocatalytic activity, degrading 96.8% of BG within 5 h. The active species involved in the degradation processes were investigated by performing degradation experiments in the presence of suitable trapping agents for superoxide radical ions (O 2 •−), hydroxyl radicals (•OH), and valence band holes (h+). It was found that O 2 •− is the main active species in the photocatalytic degradation of BG by CdS@CuInS 2. Moreover, the photocatalytic conversion of 4-nitrophenol was also enhanced up to 95.5% under visible light irradiation, and h+ is the main active species involved in the conversion. This work opens new avenues for the development of highly efficient photocatalysts for practical wastewater remediation. The effect of CdS on structural, optical, and morphological properties of the CuInS 2 synthesized using a microwave method for photocatalytic degradation of brilliant green and conversion of 4-nitrophenol. [Display omitted] • CuInS 2 and CdS@CuInS 2 synthesized using microwave-assisted method. • Effect of CdS on the structural, optical, and morphological properties of CuInS 2. • Photocatalytic degradation brilliant green using CuInS 2 and CdS@CuInS 2. • Photocatalytic conversion of 4-nitrophenol using CuInS 2 and CdS@CuInS 2. • Determination of active species involved in the photocatalytic processes. [ABSTRACT FROM AUTHOR]

Kraft lignin (KL) holds significant potential as a renewable resource for the development of innovative materials that are currently not fully utilized. In this study, a novel iminated lignin (IL) was synthesized by grafting primary amine lignin (N−KL) onto salicylaldehyde. The effects of the dosage and reaction temperature on the nitrogen content of N-KL were evaluated. The maximum nitrogen content in N-KL reached to 3.32 %. Characterization by spectroscopy techniques (FT-IR, XPS, and NMR), elemental analysis, and gel permeation chromatography confirmed the imination of lignin. Additionally, the antioxidant activity of the lignin samples was investigated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability. Moreover, the DPPH radical scavenging capacity of IL-6 (IC 50 = 38.6 ± 3.9 μg/mL) was close to that of commercial antioxidant butylated hydroxytoluene (BHT) (IC 50 = 37.7 ± 4.5 μg/mL). Furthermore, the adsorption equilibrium results indicated that IL-6 had a maximum uptake of 115.6 mg/g Pb2+, which was 3.2-fold higher than that of KL. Kinetic adsorption experiments suggested that IL-6 adsorption follows a pseudo-second-order model. Therefore, the synthesized iminated lignin is a promising candidate for the development of environmentally friendly materials with applications as an antioxidant and lead-ion adsorbent. [Display omitted] • The developed synthesis process for iminated lignin is facile and green. • Introducing amino and imine groups into kraft lignin boosts its antioxidant activity. • Iminated lignin demonstrates a notable ability to scavenge lead ions. • Pb(II) adsorption on iminated lignin relies mainly on its chelation with N atoms. [ABSTRACT FROM AUTHOR]

[Display omitted] • Kinetics of fHAT and SET mechanism of HOO• and CH 3 OO• scavenging by α-tocopherol and its derivatives was theoretically estimated. • M06-2X functional reproduces experimentally determined rate constants of HOO• scavenging by Trolox and PMHC better than the M05-2X functional. • Rate constant of HOO• scavenging in pentyl ethanoate is also estimated by using Snelgrove−Ingold equation and Abraham's β 2 H solvent parameter. • α-CEHC, ultimate catabolite of α-tocopherol, has higher HOO• and CH 3 OO• scavenging and iron chelating potency than parent molecule. In this research, antioxidant potency (in terms of peroxyl radical scavenging and catalytic iron ions sequestration) of α-tocopherol and its analogues, has been theoretically investigated. A DFT based kinetic estimation of HOO• radical scavenging potency of PMHC (lipophilic α-TOH derivative) and Trolox (hydrophilic α-TOH derivative) was performed in eight solvents of different polarity. Calculations employing M06-2X functional, accompanied by 6-311++G(d,p) basis set and SMD solvation model, were found as more accurate in reproducing experimentally determined rate constants than M05-2X functional. Rate constant of Trolox in pentyl ethanoate also was estimated by using Snelgrove−Ingold equation and Abraham's β 2 H solvent parameter. Scavenging of CH 3 OO• and HOO• radicals, which is influenced by location, orientation, and dynamics of α-TOH and its derivatives in the membrane lipid bilayer, was estimated by using M06-2X functional. Position of α-TOH phenolic OH group is opposite to that of its metabolite α-CEHC: α-TOH's OH group is located at the membrane-water interface, and α-CEHC's OH group is deeply buried into the bilayer. In the aqueous phase both fHAT and SET were investigated, and inside the bilayer only fHAT was considered as feasible. The spontaneous disproportionation of HOO•/O 2 •− in aqueous solutions should be taken into account to predict potency of antioxidant in scavenging of HOO• radicals. Iron chelating ability of α-TOH and α-CEHC was also investigated. Obtained results indicate α-CEHC, α-tocopherol final catabolite, as more potent scavenger of CH 3 OO• and HOO• radicals and iron ions chelator than the parent molecule. [ABSTRACT FROM AUTHOR]

The reactions of protein oxidation play a significant role in many biological processes, especially in diseases development. Therefore, it is important to understand, how the protein molecule behaves in the presence of oxidants. In the present work, photo-oxidation of phytohormone-binding plant protein (VrPhBP) was investigated using light and 3-carboxybenzophenone (3CB) as a sensitizer (one electron oxidant). The protein interacts with the sensitizer in the ground state forming a weak binding complex leading to the presence of bound and free 3CB in solution. The early events and transient species (such as radicals and radical ions) formed during irradiation were characterised by transient spectroscopy showing the formation of the sulphur radical cation Met>S●+ (stabilized by (S ∴ N)+)and the tyrosyl radical TyrO● on VrPhBP. Thus the 3CB excited triplet state was quenched by the Met and Tyr residues and mostly by Met (based on the deconvoluted transient absorption spectra).The presence of a Tyr side chain in the vicinity of a Met residue results in intramolecular electron transfer from Tyr to the Met>S●+ radical cation, leading to regeneration of the thioether side chain and formation of TyrO●. The presence of other side chains close to Met, such as Arg or Lys can induce the stabilization of Met>S●+ via the formation of two-centered three-electron bonded species (S ∴ N)+. The transient species were additionally confirmed by stable product analysis. Based on SDS-PAGE, chromatography and mass spectrometry, the formation of methionine sulphoxide and Met-3CB adduct was identified together with di-Tyr cross links. On the basis of the experimental results the overall mechanism of VrPhBP photo-oxidation, from its early events to the formation of stable products, is described. In addition, a good correlation between the mechanisms of photooxidation of model compounds such as Met derivatives and peptides and those for real biological systems is emphasized. [Display omitted] • One-electron photo-oxidation of methionine residue in proteins highly depends on the environment. • Electron transfer from tyrosine residue to radicals formed on methionine in protein models occurs like in model compounds, e.g. Met-Enkephalin. • The major product of photo-oxidation of Met residue in proteins in ate absence of oxygen is methionine sulphoxide and adduct with quencher molecule – 3-carboxybenzophenone • The mechanism of photo-oxidation of Met-residue was described by time resolved methods and stable products identifications. [ABSTRACT FROM AUTHOR]

• Isotope signatures of sulfur species and pyrite have been studied in hydrothermal fluids. • MDF equilibrium and kinetic SO 4 -H 2 S and pyrite-H 2 S factors are quantified. • No MIF anomalies are detected in the presence of sulfur radical ions. • Isotope signature of molecular sulfur fingerprints the different mechanisms of S0 formation. • Several environments offer potential for MIF generation in fluid-mineral systems. This study is aimed to evaluate the role played by the sulfur radical ions (S 3 − and S 2 −) and molecular sulfur (S0) on sulfur isotope fractionation and to investigate if these species may leave an isotope fingerprint in hydrothermal systems. For this purpose, we combined (i) experiments using a hydrothermal reactor with aqueous S 3 −(S 2 −)-S0-sulfate-sulfide fluids and pyrite across a wide range of temperatures (300–450 °C), pressures (300–800 bars), fluid acidity (4 < pH < 8) and with elevated total sulfur concentrations (0.1–1.0 mol/kg fluid) favorable for formation of those polymeric sulfur species, (ii) precise quadruple S isotope analyses of the different S-bearing aqueous species in sampled fluids and in-situ precipitated pyrite, and (iii) thermodynamic modeling of sulfur aqueous speciation and solubility. Our results quantitatively confirm both equilibrium and kinetic SO 4 -H 2 S and pyrite-H 2 S mass dependent fractionation (MDF) factors previously established using extensive experimental and natural data from more dilute fluids in which polymeric sulfur species are negligible. MDF signatures of S0 measured in the sampled fluids of this study reveal different S0-forming pathways such as (i) breakdown on cooling of S 3 − (and S 2 −) and other chain-like S0 polymers only stable at high temperature and being isotopically identical to H 2 S; (ii) cyclooctasulfur (S 8 0, liquid or solid) precipitating by recombination of sulfate and sulfide and/or by exchange with polysulfide dianions (S n 2−) on cooling and being slightly 34S-enriched compared to H 2 S (by ∼2‰ of δ34S); and iii) a different type of S0 resulting from thiosulfate irreversible breakdown and being highly 34S-depleted (by ∼12‰) relative to H 2 S. Our data do not show any significant mass independent fractionation (MIF) of 33S and 36S, with Δ33S and Δ36S values of any S aqueous species and pyrite being within ±0.1‰ and ±1.0‰, respectively. Therefore, under the investigated experimental conditions, the radical S 3 − ion is unlikely to generate significant MIF in the hydrothermal fluid phase and in pyrite and native sulfur precipitated therefrom. Our study supports the existing interpretations of small Δ33S and Δ36S variations between sulfide/sulfate-bearing fluid and pyrite as MDF in terms of reaction kinetics, different reaction pathways, and mass conservation effects such as mixing of S reservoirs or Rayleigh distillation. Our data extend, across a wider range of sulfur concentration and chemical speciation, the existing multiple S isotopes models that exploit such variations as a complement to the traditional δ34S tracer to monitor the approach to equilibrium and evolution of hydrothermal fluids. [ABSTRACT FROM AUTHOR]

New Schiff base germanate derivative containing the chain Ar–C=N→Ge←N=C–Ar was synthesized and characterized by physical methods including X-ray diffraction. The stability of the corresponding radical anion obtained electrochemically was confirmed by cyclic voltammetry, the results were compared with UV-VIS data and quantum chemical calculations. [ABSTRACT FROM AUTHOR]

Carbon nanotips and nanowhiskers were produced through etching of an amorphous carbon layer (ACL) by controlling the plasma environment. Discharge types and different gases induced significant changes in the carbon nanostructure owing to the independent or combined effect of ions and radicals. The carbon nanowhiskers were obtained by both ion bombardment and oxygen radicals in a radiofrequency (RF) capacitively coupled plasma (CCP) under the O 2 gas environment. In contrast, RF CCP in an Ar gas environment or inductively coupled plasma (ICP) in an O 2 gas environment formed carbon nanotips or nanodots, respectively, through the rearrangement of carbon atoms due to ion bombardment or chemical etching by radicals. The carbon nanowhiskers and nanotips were vertically grown in these plasma conditions due to the effect of an electric field, and its effect on the vertical growth was confirmed when using ICPs with RF bias where the electric field of the plasma sheath is controlled. Raman spectroscopy and high-resolution transmission electron microscopy measurements indicate that the crystalline area in carbon nanostructures increased during the rearrangement of the ACL induced by ion bombardment and radical reaction. Image 1 [ABSTRACT FROM AUTHOR]

• Four polysaccharides of Amana edulis were sulfated, phosphorylated and carboxymethylated, respectively. • P-AEPs displayed the highest DPPH, hydroxyl radical and ferrous ions radical scavenging ability. • S-AEPs were observed with high reducing ability. • C-AEPs maintained moderately stable antioxidant ability. In this study, four sequentially extracted polysaccharides (AEPs) from Amana edulis were modified by sulphation, phosphorylation, and carboxylation modifications (S-AEPs, P-AEPs, C-AEPs), and compared for their anti-oxidant activities. After modification, sugar and protein contents were decreased and uronic acid content was increased in comparison to native AEPs. UV absorption showed similar maximum absorption peaks of modified derivatives which indicated their homogeneous nature. FTIR spectra confirmed the conversion of hydroxyl groups to O S, COO, and P OH bonds, respectively. The phosphorylated derivatives (P-AEPs) displayed the highest DPPH, hydroxyl radical, and ferrous ions radical scavenging abilities. Sulfated polysaccharides (S-AEPs) were observed with high reducing ability. The C-AEPs maintained the stable antioxidant properties after carboxylation modification. Our results indicated that the chemical modification of different polysaccharide components has significantly affected their antioxidant potential for their use in food industry and human health. [ABSTRACT FROM AUTHOR]

• ZnO NPs were biosynthesized from Barleria mysorensis by hydrothermal process. • Biosynthesized ZnO NPs were of high quality, hexagonal shape with structural stability. • Biosynthesized ZnO NPs efficiently degraded MB dye with potential reusability. • The photodegradation of MB dye by ZnO NPs followed the pseudo-first-order kinetics. • Mineralization studies proved ZnO NPs didn't produce non-toxic end products. During the study, Barleria mysorensis B.Heyne ex Roth was selected for biosynthesizing zinc oxide nanoparticles (ZnO NPs) and evaluating its photocatalytic properties. The structural and morphological characterization of the synthesized particles were performed by UV–Vis diffusion reflectance spectroscopy (UV–Vis DRS), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDS), Fourier-Transform Infrared (FT-IR) spectroscopy and Braunauer–Emmett–Teller (BET) studies. The results indicate high-quality ZnO NPs of 34.36 nm crystallite size with 92.32 % elemental purity (ZnO) and an energy band gap of 3.18 eV. According to the BET study, the synthesized particles had a surface area of 21.626 m2 g–1 with 0.001354 cm3g−1 (p/po=0.908) total pore volume of 0.001354 cm3g−1 (p/po=0.908) and 7.34 nm of mean pore diameter. The electron resonance spectroscopy (ESR) revealed that upon interaction of ZnO NPs revealed the formation superoxide radical ions. The photocatalytic degradation of methylene blue (MB) dye using the synthesized nanoparticles revealed a degradation efficiency of approximately 91.32 % within 120 min of exposure at a rate constant of 18.34 × 10−3 min−1 and it was also noted that the dye degradation process followed pseudo-first-order kinetics. Besides, reusability and structural stability studies of ZnO NPs as photocatalysts revealed a stable performance up to five cycles. In addition, mineralization studies revealed a steady decrease in COD and TOC content with an increase in reaction time, indicating an improvement in mineralization. In conclusion, biosynthesized ZnO NPs get rid of the dye and lower the solution's COD and TOC, ensuring that the dye in question breaks down and non-toxic end products are made. [Display omitted] [ABSTRACT FROM AUTHOR]

Damage caused to biological targets through sunlight photosensitized reaction is of paramount importance due to their potential effects on human health. In these processes, a chemical alteration of a biomolecule may occur as a result of the initial radiation absorption by another chemical species called photosensitizer. In this respect, pterins are endogenous photosensitizers able of inducing chemical modifications in DNA, proteins and lipids. These molecules are present in many living organisms and play different biological functions. In humans, aromatic pterins (Pt) accumulate in the depigmentation patches on the skin of patients suffering vitiligo. Interestingly, 5-hydroxytryptophan (5-OH-Trp), a common oxidation product of tryptophan acting as a potential endogenous antioxidant, is also present in the skin under oxidative stress conditions, such as those produced by vitiligo. However, the photochemical interaction between Pt and 5-OH-Trp has not been considered yet. With this background, the goal of the present work is to deepen the knowledge of the capability of Pt to photoinduce damage to 5-OH-Trp. By combining different analytical and spectroscopic techniques, we establish that 5-OH-Trp is damaged by Pt through a photosensitized type I process initiated by an electron transfer from the 5-OH-Trp to the Pt triplet excited state that yield the corresponding radical ions. In air-equilibrated aqueous solution four products were identified, two of which correspond to 5-OH-Trp dimers, while the others are a 5-OH-Trp trimer and a dione, in which the 5-OH-Trp has incorporated an oxygen atom. No consumption of Pt was observed in the presence of O 2. However, in the absence of O 2 , further free-radical reactions lead to the reduction of the photosensitizer, and dimers and trimer were the only 5-OH-Trp-derived products detected. The biomedical implications of the generation of this kind of products, in proteins, are discussed. [Display omitted] • 1-Pterins, endogenous sensitizers, induce the photodegradation of 5-hydroxytryptophan. • Photosensitization is initiated by the one-electron oxidation of 5-hydroxytryptophan. • The photodegradation of 5-hydroxytryptophan strongly depends on the O 2 concentration. • Regardless of the O 2 concentration, dimer and trimer of 5-hydroxytryptophan are formed. • In the presence of O 2 a dione product, which absorbs in the visible region, is generated. [ABSTRACT FROM AUTHOR]

A standard sample mixture containing thirty-seven fatty acid methyl esters (FAMEs) was measured by femtosecond laser ionization mass spectrometry. FAME molecules with double bonds were efficiently ionized via resonance-enhanced two-photon ionization by absorbing the first photon at 206 nm at the edge of the absorption band of the π→π* transition and subsequently ionized by absorbing the second photon at 257 nm. The intensity of the molecular radical ion was enhanced significantly using this two-color ionization scheme, which minimizes the excess energy in the ionized state, when compared with electron ionization mass spectrometry and vacuum-ultraviolet photoionization mass spectrometry. This approach was then used for the reliable identification of FAMEs contained in an actual sample of biofuel. [Display omitted] • Fatty acid methyl esters (FAMEs) were measured by mass spectrometry. • FAMEs were ionized using a femtosecond laser as the ionization source (fsLIMS). • FAMEs were ionized using a two-color two-photon ionization scheme at 206/257 nm. • The signal intensity of a molecular radical ion was enhanced for unsaturated FAMEs. • FAMEs contained in a real sample of biofuel was determined using this technique. [ABSTRACT FROM AUTHOR]

The pursuit of sustainable and inexpensive systems for the degradation of organic aquatic pollutants working under sunlight or even without irradiation is still open. Herein, an amorphous titanium oxide modified with dibenzoylmethane, an aromatic diketone, is proposed as a solar photocatalyst showing oxidative activity also in the dark. Ti(IV)-dibenzoylmethanate (dbm) complexes form during the sol-gel synthesis and are dispersed throughout the oxide gel structure. This ligand-to-metal charge transfer complex plays a dual role: it enables visible light absorption, narrowing the apparent band gap, and provides localized surface charge, promoting the spontaneous formation and stabilization of superoxide radical ions by reduction of O 2. The activity of the TiO 2 -dbm hybrid was assessed in the removal of methylene blue from aqueous solution. The results demonstrated a rather stable photocatalytic activity under natural sunlight, exceeding 80% dye removal after 1 h in four subsequent tests, a value that was mostly recovered after a mild regeneration. Considerable efficiencies were also achieved in the dark, owing to the immobilized superoxide radicals acting as initiators of degradation pathways. Finally, the influence of the operating conditions (pH, illumination, mixing method, water contact) on the efficiency and durability of the performances was evaluated to survey the long-term utilization in water decontamination. The behaviour of this hybrid material resembles a "photocatalytic memory" effect and may widen the perspectives for the development of heterogeneous advanced oxidation processes. [Display omitted] • TiO 2 -dibenzoylmethane hybrid catalysts are produced by a sol-gel route. • The ligand-to-metal charge transfer complexes activate visible light response. • The complexes induce the formation of stable superoxide radicals at the surface. • Methylene blue removal from water is achieved both under sunlight and in the dark. • Solar light improves the oxidative degradation rate and the reuse stability. [ABSTRACT FROM AUTHOR]

Organic materials were developed for use as tissue-equivalent dosimeters operating on the principle of organic radiophotoluminescence (ORPL) based on the emission-switching of fluorescein and p -benzoquinone (BQ) in polymethylmethacrylate and propylene carbonate. The BQ-derived radical ions generated by X-ray irradiation open the lactone ring of fluorescein, thereby producing emissive molecules. The fluorescence properties and potential applications of the dosimeters were investigated. At the optimal composition (1 wt% fluorescein and 10 wt% BQ), the linear range was 0–4 Gy. Furthermore, the dose sensitivity in this range was significantly higher than that of Ag-phosphate glass. The sensitivity range and high radiation-dose-sensitivity make the material suitable for use in radiotherapy. • Organic radiophotoluminescence (ORPL) that can be used as tissue-equivalent dosimeters was achieved. • The sensitivity range and high radiation-dose-sensitivity make the material suitable for use in radiotherapy. • ORPL based on the emission-switching of fluorescein and p-benzoquinone (BQ) in the polymers were investigated. [ABSTRACT FROM AUTHOR]

Curcumin (CU), a natural polyphenol exhibits free radical scavenging activity by three main mechanisms namely, HAT (hydrogen atom transfer), SPLET (sequential proton loss electron transfer) and SET-PT (sequential electron transfer-proton-transfer). In this study, the influence of structural modification of curcumin to its isoxazole (CI) and pyrazole (CP) on their free radical scavenging mechanism has been investigated. For this, CI and CP were first screened for their free radical scavenging ability using different free radicals like DPPH• (1,1-diphenyl-2-picrylhydrazyl), ABTS•– (2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)), O 2 •– (superoxide), N 3 • (azide), CCl 3 O 2 • (trichloromethyl peroxyl), lipid peroxyl (LOO•) radicals, FRAP (Ferric reducing antioxidant power) assay and the results were compared with CU. The reaction mechanism was explained by complementing the experimental results with molecular descriptors obtained from quantum chemical calculations. The dependence of the scavenging activity on the acidity of the solvent indicated that CU and its derivatives reacted with DPPH•, ABTS•–, O 2 •–, LOO• radicals and ferric ion by SPLET mechanism, while they reacted with N 3 • and CCl 3 O 2 • radical by SET-PT mechanism. In case of free radicals neutralized by SPLET mechanism, the IC 50 value of the polyphenols (the concentration of the polyphenol required to scavenge 50% radical) increased in the order CU < CI ≈ CP. However when they neutralized the free radicals by SET-PT mechanism, their reactivity increased in the order CP > CI > CU. Using DFT calculations, the pK a of the parent molecule and their corresponding one-electron oxidized radicals were calculated. In the case of parent molecule the pK a increased in the order CU < CI ≈ CP, however in the case of the one-electron oxidized radical the trend was reversed (CP < CI < CU), indicating that modification of diketo moiety of CU to isoxazole and pyrazole govern the mechanism under SET-PT. The intrinsic stability of the phenoxyl radical formed by the free radical scavenging of CU, CI and CP was expressed in terms of radical delocalization values (RDV), which showed that the phenoxyl radical of CP was more stable as compared to CI and CU. The lower pK a value of the radical of CP as compared to CU and CI indicated that modification of CU to CP tends to orient the reaction mechanism from SPLET to SET-PT. These studies revealed that substitution of the diketo moiety with the pyrazole moiety improved the peroxyl scavenging as well as the stability of the resulting radical, serving pyrazole moiety as a useful template for the rational design of novel antioxidants that are more effective than the curcumin. Image 1 • Curcumin pyrazole (CP) & isoxazole (CI) are diketo modified derivatives of curcumin. • Physico-chemical properties were used to explain antioxidant activity. • Radical delocalization value was used to measure the stability of the phenoxyl radical. • From DFT calculation CP have higher HOMO value and low bond dissociation energy. • Lower pKa of CP radical cation tends to orient the reaction mechanism by SET-PT. [ABSTRACT FROM AUTHOR]

In the current work, for the first time, the conjugation structure, electronic properties, and UV–visible spectral characteristics of a series of 1-amino-9,10-anthraquinone oligomers, oligo(AAQs), are studied using the density functional theory (DFT) method. The required computations are performed on the 2AAQ, 4AAQ, 6AAQ, and 8AAQ oligomers in their ground state and radical ion forms as the potential candidates for the conducting polymers. The geometric characteristics, frontier molecular band gap energy, ionization potential, electron affinity, and UV–visible spectral characteristics of the understudied oligo(AAQs) are investigated by the B3LYP/6-31G(d,p) level of theory and the time-dependent DFT method. The results obtained show that the oligo(AAQ) chains are twisted from the planarity structure due to the steric strain of the AAQ repeating units along the oligomer chain. This deviation from planarity decreases as the oligomer chain increases. Our calculations show that the n- and p-doped oligo(AAQ)s are more favorable than their ground states and that the doped phases have more satisfactory properties, reflecting the electron and hole transport characteristics for conductivity. The results obtained allow one to understand the qualitative structure-property correlation and a new vision into the conduction and the emission process of poly(AAQ) for a better use in the opto-electronic applications. "A comprehensive theoretical study was carried out on a co-oligomer made up of the aniline (AN) and 1-amino-9,10-anthraquinone (AAQ) monomers. This novel theoretical study allows us to understand the structure-property correlation and a new insight in to the conduction process and the emission of poly(AN-AAQ) for better use in opto-electronic devices". Image 1 • The growth of a series of 1-amino-9,10-anthraquinone oligomers, oligo(AAQ)s, yielded an increase in their conjugation length. • The HOMO-LUMO gaps for the oligo(AAQ)s decreased significantly in the p- and n-doped states. • The IP and EA values for the oligo(AAQ)s correlated linearly with the inverse oligomer length values. • The UV–visible spectra for the oligo(AAQ)s showed a red shift with increase in the oligomer chain length. • The results obtained can be used to predict the poly(AAQ) properties. [ABSTRACT FROM AUTHOR]

• Investigating the validity of colorimetric methods to screen phenolic bioactives. • Identification and quantification of phenolics from grape processing by-products. • Peroxyl radical and ferric ion as oxidants of biological importance. • Reduction of NF-κB activation was anticipated by ORAC and FRAP assays. • Decrease in the activation of NF-κB may be attributed to antioxidant pre-treatment. Free radical imbalance is associated with several chronic diseases. However, recent controversies have put in check the validity of colorimetric methods to screen the functionality of polyphenols. Therefore, in this study two antioxidant methods, based on chemical reactions, were tested for their ability in anticipating the reduction of the activation of NF-κB using LPS-activated RAW 264.7 macrophages, selected as a biological model. Grape processing by-products from winemaking showed higher total phenolic content (TPC), antioxidant capacity towards peroxyl radical (31.1%) as well as reducing power (39.5%) than those of grape juice by-products. The same trend was observed when these samples were tested against LPS-activated RAW 264.7 macrophages by reducing the activation NF-κB. Feedstocks containing higher TPC and corresponding ORAC and FRAP results translated to higher reduction in the activation of NF-κB (36.5%). Therefore, this contribution demonstrates that colorimetric methods are still important screening tools owing their simplicity and widespread application. [ABSTRACT FROM AUTHOR]

{100} planes of CeO 2 are unstable polar surfaces and important to enhance the oxygen storage capacity. However, a convenient method is still needed for the synthesis of ceria nanocubes which expose six {100} facets. Here, a new and facile synthesis strategy has been developed to synthesize single-crystalline nanocubes of CeO 2. According to transmission electron microscopy, these nanocubes are enclosed by six {100} facets. It is proved that in the synthesis process, the acetate radical ions would adsorb on the positive charged Ce(OH) 3 formed from the reaction of Ce3+ and ammonia, then partially inhibit the redox between Ce(OH) 3 and NO 3 − and protect the {100} facets during crystal growth. Meanwhile, the Ce4+ ions would act as crystal seeds to facilitate the formation of single crystals. Both of the addition of Ce4+ ions and CH 3 COO− ions are necessary for the synthesis of monocrystal ceria nanocubes. Throughout the synthesis process, it is moderate reaction conditions that the pressure is atmospheric pressure and temperature is no higher than 80 °C. [ABSTRACT FROM AUTHOR]

Integrated photocatalytic composite adsorbents (IPCA) are used to degrade toxic organic and inorganic compounds in presence of UV/visible light irradiation. The compound preserves all the existing features of individual components and at the same time overcome drawbacks like rapid recombination of photogenerated electrons, low absorptivity and hindrance effect of the photocatalyst. Herein, an integrated Photocatalytic Chitosan-La3+-Graphite composite adsorbent was synthesized and the resultant composites were characterized by FTIR, XRD, TGA, EDX and SEM analysis. The UV–visible diffusion reflectance spectroscopy (UV–vis DRS) was used for the band gap measurement and it was found to be 3.2 eV. An aqueous solution of methylene blue (MB) dye (30 mL of 100 mg/L) was used to study the photocatalytic efficiency of the prepared IPCA. The Chitosan-La3+-Graphite Composite (CS-La-GR) (100 mg of dosage) exhibits enhanced photocatalytic degradation efficiency (93.5% in 40 min) for Methylene blue under UV light irradiation. The highest photodegradation was due to the stronger adsorption of MB dye on the surface of highly porous IPCA. Moreover, the reactive species, ·OH radical and O 2 ·− radical ions play a major role in the photocatalytic degradation of Methylene blue over composite photocatalyst. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • UVA irradiation induced FeIII-NTA reduction for S 2 O 8 2− activation at neutral pH. • Both SO 4 − and HO were involved in UVA/FeIII-NTA/S 2 O 8 2− process. • The rate constant of NTA reacting with SO 4 − was determined at 5.89 × 107 M−1 s−1. • The critical NTA:FeIII molar ratio for UVA/FeIII-NTA/S 2 O 8 2− process was 1:1. • UVA/FeIII-NTA/S 2 O 8 2− was less effective than UVA/FeIII-NTA/H 2 O 2 in degrading CBZ. Abstract Ferrous ion (FeII)-induced activation of persulfate (S 2 O 8 2−), reference to the generation of sulfate radical (SO 4 −), has attracted considerable attention in water treatment for refractory organic contaminants removal. However, two major challenges, i.e., the required acidic pH condition and the extremely slow FeIII/FeII redox cycle, limit the application of FeII/S 2 O 8 2− process. Herein, the present work addresses S 2 O 8 2− activation in aqueous solutions at neutral pH by a ferric-nitrilotriacetic (FeIII-NTA) complex under low pressure UVA irradiation. The results showed that UVA irradiation-induced FeIII-NTA reduction could effectively enhance FeIII/FeII redox cycle for the S 2 O 8 2− activation under neutral pH condition. Electron spin resonance spectroscopy (ESR) and radicals quenching tests indicated that the major reactive species included SO 4 − and hydroxy radicals (HO) in UVA/FeIII-NTA/S 2 O 8 2− process, which contributed more than 80% degradation of a model compound carbamazepine (CBZ). In addition, comprehensive investigations were conducted on the important parameters including NTA:FeIII molar ratio, initial pH, FeIII-NTA and S 2 O 8 2− dosages and their impacts on CBZ degradation kinetics. The critical NTA:FeIII molar ratio was determined at 1:1, above this ratio the excess NTA would act as a scavenger of SO 4 −/HO thereby inhibiting the degradation of CBZ. The secondary reaction rate constant of NTA with SO 4 − was determined at 5.89 × 107 M−1 s−1. Moreover, the degradation of CBZ by UVA/FeIII-NTA/S 2 O 8 2− process in real water matrix (lake water, groundwater and tap water) with environmentally relevant concentration were conducted, and the efficacies were compared with UVA/FeIII-NTA/H 2 O 2 (i.e., photo-Fenton-like) process. The degradation mechanism and pathway of CBZ were proposed on the basis of the identified intermediates by using LC-QTOF-MS technique. [ABSTRACT FROM AUTHOR]

Abstract Today, the problem of antimicrobial resistance is the most important cause of morbidity and mortality in the treatment of infectious diseases worldwide. Therefore, alternative treatment strategies are important for controlling infectious diseases. In the basic principle of antimicrobial photodynamic therapy (aPDT), when harmless light at the appropriate wavelength absorbed by the photosensitizer, undergoes a transition from a ground state to a triplet state. The triplet state photosensitizer can interact with enzym and substrate molecules to produce free radicals and radical ions, or with molecular oxygen resulting in the generation of singlet oxygen which leads to cell cytotoxicity of the microorganism. For this purpose, axially {4-[(1 E)-3-oxo-3-(2-thienyl) prop-1-en-1-yl]phenoxy} group substituted silicon phthalocyanine (Es-SiPc) and subphthalocyanine (Es-SubPc) were synthesized by reaction of SiPcCl 2 , SubPcCl with (2 E)-3-(4-hydroxyphenyl)-1-(2-thienyl)prop-2-en-1-one in the presence of NaH in toluene. The new Es-SiPc and Es-SubPc were characterized by standard spectroscopy methods. The effects of aPDT in the presence of phthalocyanines were investigated against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) strains. Also, singlet oxygen generation of Es-SiPc and Es-SubPc were investigated. Our results suggest that the aPDT in the presence of newly synthesized Es-SiPc and Es-SubPc has promising antibacterial effects on Gram-positive and Gram-negative bacteria. Graphical abstract Image 1 Highlights ► Synthesis of new silicon phthalocyanine. ► Synthesis of subphthalocyanine ► Antimicrobial photodynamic activity of phthalocyanines. [ABSTRACT FROM AUTHOR]

Three new lanthanide complexes based on a nitronyl nitroxide radical [Ln(hfac) 3 (NIT3Ph3Py)] 2 (Ln = Dy(1), Tb(2), Gd(3); hfac = hexafluoroacetylacetonate, NIT3Ph3Py = 2-(3′-(3″-pyridyl)-phenyl)-4,4,5,5- tetramethylimidazoline-1-oxyl-3-oxide) have been successfully synthesized, characterized structurally and magnetically. Single crystal X-ray diffraction analysis reveals that complexes 1 – 3 are isomorphous in which NIT3Ph3Py acts as a bridging ligand linking two Ln(III) ions through the nitrogen atom of pyridine ring and the oxygen atom of N O group to form a four-spin system. The magnetic studies reveal that the ferromagnetic interactions between the Ln(III) ions and nitronyl nitroxide radicals in the complexes. Moreover, alternating current (ac) magnetic susceptibilities show that Dy(III) complex exhibits frequency-dependent signals at low temperature. Three cyclic lanthanide–nitronyl nitroxide radical complexes were successfully synthesized and characterized magnetically. The magnetic studies reveal that Dy(III) complex displays frequency-dependent signals at low temperature. Unlabelled Image • Three isomorphous Ln-radical complexes • Ferromagnetic coupling interaction between Ln(III) ions and radicals • Dy(III) complex exhibits frequency-dependent out-of-phase signals. [ABSTRACT FROM AUTHOR]

A series of isoprene and sodium styrene sulfonate copolymers (poly(I- co -NaSS)) was synthesized with systematically varied concentrations of ions using radical emulsion polymerization. Their chemical structures and morphologies were characterized and structure-mechanical relationships were determined. The SAXS scattering profiles and the thermal properties remained unchanged as ion content increased. In contrast, the toughness and stiffness of the copolymers increased and the adhesion strength was significantly improved as the ion content increased from 1.2 mol % to 4.6 mol % NaSS. Image 1 • Copolymers of isoprene and sodium styrene sulfonate create ionomers with properties that change in relation to ion content. • Large-scale aggregation was not shown in thermal properties, or small angle x-ray scattering. • As ion concentration increased properties including stress relaxation, tensile, hysteresis, and adhesion improved. • Property changes are due to chemical crosslinking and systematic increases in physical crosslinking with ion content. [ABSTRACT FROM AUTHOR]

Highlights • We evaluated thirteen hydrophobic ionic liquids (ILs) for destruction of three halogenated hydrocarbons. • We evaluated the effect of contact time on the destruction efficiency of ILs. • We also assessed the effect of potassium superoxide (KO 2) dose on the destruction efficiency. • We interpolated physico-chemical properties of halogenated hydrocarbons regarding the destruction efficiency. Abstract Ionic liquids (ILs) have been investigated as a media for destruction of halogenated hydrocarbons (HHCs) because of their affinity to solubilize pollutants, hydrophobicity, ability to generate and maintain free radicals, and long term stability with superoxide ion radical (O 2 −). Three HHCs (CCl₄, CHCl 3 , and CHBr 3) were successfully destructed by O 2 − in 13 hydrophobic ILs, including two piperidinium (PIP-ILs), four pyrrolidinium (PYRR-ILs), and seven ammonium-cation based ILs (AM-ILs). The effects of contact time and potassium superoxide (KO 2) dose on the destruction efficiency were evaluated using analysis of variance. 1-propyl -1- methylpiperidinium, 1-octyl-1-Methylpyrrolidinium, and octyltriethylammonium paired with bis (trifluoromethylsulfonyl) imide were found to be the best performers amongst PIP-ILs, PYRR-ILs, and AM-ILs. CHCl 3 , CCl₄ and CHBr 3 consumed about 8, 11, and 14 KO 2 /HHC mole ratio to achieve 95% of optimum destruction efficiency. High viscosity was identified as the main drawback of [N8881][Tf 2 N] and [N4441][Tf 2 N]. Destruction was moderately fast and steady state efficiency was achieved within 30 min. The strong correlations between empirical polarity E T N of HHCs, work as co-solvents, and destruction efficiencies were obtained with R 2 values higher than 0.99. The study presents a useful insight to use ILs as alternative solvents for treatment of hazardous wastes. [ABSTRACT FROM AUTHOR]

This paper reports for the first time the strong cathodic electrochemiluminescence (ECL) behavior of quinoline, isoquinoline and their derivatives in aqueous solution with K 2 S 2 O 8 as coreactant. The effects of K 2 S 2 O 8 concentration, pH and scan rate on the ECL intensity have been studied in detail. Calculations of the HOMO-LUMO energy gap for the ECL reaction indicated that isoquinoline is more likely to produce an excited state radical ion than quinoline. The effects of different functional groups on the ECL of isoquinoline were then compared and a possible ECL reaction mechanism was discussed. This work provides a simple and sensitive ECL method for the detection of quinoline and isoquinoline, which are important drug intermediates. Unlabelled Image • Isoquinoline showed excellent electrochemiluminescence (ECL) performance when using K 2 S 2 O 8 as coreactant. • Quinoline and isoquinoline have similar structures, but the ECL properties are quite different. • Electron-withdrawing and electron-donating functional groups have opposite effects on the ECL of isoquinoline. [ABSTRACT FROM AUTHOR]

Microplastics are recognized as an emerging critical issue for the environment. Here an innovative chemical approach for the treatment of microplastics is proposed, based on an oxidative process that does not require any direct energy source (irradiation or heat). Linear low-density polyethylene (LLDPE) was selected as target commodity polymer, due to its widespread use, chemical inertness and inefficient recycling. This route is based on a hybrid material coupling titanium oxide with a bio-waste, rosin, mainly constituted by abietic acid, through a simple sol-gel synthesis procedure. The ligand-to-metal charge transfer complexes formed between rosin and Ti4+ allow the generation of reactive oxygen species without UV irradiation for its activation. In agreement with theorical calculations, superoxide radical ions are stabilized at ambient conditions on the surface of the hybrid TiO 2. Consequently, an impressive degradation of LLDPE is observed after 1 month exposure in a batch configuration under indirect daylight, as evidenced by the products revealed by gas chromatography-mass spectrometry analysis and by chemical and structural modifications of the polymer surface. In a context of waste exploitation, this innovative and sustainable approach represents a promising cost-effective strategy for the oxidative degradation of microplastics, without producing any toxic by-products. [Display omitted] • A new hybrid material (T- Abi) was synthesized by a waste-to-wealth approach. • Rosin bio-waste acts as ligand to Ti4+ forming charge-transfer complex. • O 2 •– radicals are generated on T- Abi without the need for any energetic source. • A new oxidative degradation process using indirect daylight is exploited. • After 1 month, alkanes, alcohols, esters are the LLDPE degradation by-products. [ABSTRACT FROM AUTHOR]