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Here, we report curvature‐induced electron spin catalysis by using solid carbon spheres as catalysts, which were synthesized using positive curvature molecular hexabromocyclopentadiene as a precursor molecule, following a radical coupling mechanism. The curvature spin of carbon is regarded as an overlapping state of σ‐ and π‐radical, which is identified by the inverse Laplace transform of pulse‐electron paramagnetic resonance. The growth mechanism of carbon spheres abiding by Kroto's model, is supported by the density functional theory study of thermodynamics and kinetics calculations. The solid carbon spheres present excellent catalytic behaviour of oxidation coupling of amines to form corresponding imines with the conversion of >99 %, selectivity of 98.7 %, and yield of 97.7 %, which is attributed to the predominantly curvature‐induced electron spin catalysis of carbon, supported by the calculation of oxygen adsorption energy. This work proposes a view of curvature‐induced spin catalysis of carbon, which opens up a research direction for curvature‐induced electron spin catalysis. [ABSTRACT FROM AUTHOR]

The heterogeneous photo-Fenton system using Fe-Co/γ-Al2O3 as a catalyst was applied in the study of sulfamethoxazole(SMX) degradation. The morphology, structure, elemental composition and metal valence distribution of Fe-Co/γ-Al2O3 were found to be relatively stable before and after the reaction. The highest SMX degradation efficiency and mineralization (The ratio of organic matter being oxidized to carbon dioxide and water) were obtained under the conditions of 15% Fe-Co loading rate, 1:1 mass ratio of Fe and Co, 1 g/L catalyst dosage, 1.5 mL 30% H2O2 dosage, 18 W UV lamp power and 60 min reaction time, which were 98% and 66%, respectively. Radical quenching experiments and electronic paramagnetic resonance (EPR) characterization revealed that ·OH played an important role in the degradation and mineralization SMX in the Fe-Co/γ-Al2O3 heterogeneous photo-Fenton system. Combined with the analysis of N, S and intermediate products, there may be three degradation pathways of SMX in the heterogeneous photo-Fenton system. This work provides a technical reference for realizing the efficient degradation and mineralization of SMX in a heterogeneous photo-Fenton reaction system. [ABSTRACT FROM AUTHOR]

Effects of xanthene dyes and aerosil nanoparticles on the structure and dynamic characteristics of the cross-linked polyurethane were investigated by the IR-spectroscopy, dynamic-mechanical analysis, and electronic paramagnetic resonance methods. Dye molecule presence causes self-association of urethane groups within polymer rigid segments, weaker interactions between urethane groups and flexible oligoether parts and increased oligoether mobility. Increased mobility of flexible segments by xanthene dyes provides the necessary beam strength due to compensating the nanofiller network effect. The most efficient polyurethane material in the radiation resistance is expected to be a polymer composite with the highest permeability and the lowest modulus of elasticity. [ABSTRACT FROM AUTHOR]

Two complexes (C6H9N2)2[CuCl4] (1) and (C5H6N2Cl)2[CuCl4] (2) have been synthesized and characterized by single‐crystal X‐ray diffraction which revealed that these phases are centrosymmetric and crystallize, respectively, in monoclinic and triclinic symmetries. The thermal properties of both complexes are investigated as well as the UV‐Vis spectroscopic, photoluminescence properties, electronic paramagnetic resonance and biological activities. The crystal packing of the two compounds is guided by N−H⋅⋅⋅Cl hydrogen bonds and offset π–π stacking interactions; these interactions contribute to the overall stabilization of the structures as they connect anions and cations together into a three‐dimensional network. In addition, the optimized molecular structure was calculated by the Density Functional Theory (DFT) method using the B3LYP function with the LanL2DZ basis set. Subsequently, the thermal behavior was studied by TGA/DTA analyses. Moreover, the optical properties were studied using optical absorption UV‐visible and photoluminescence (PL) spectroscopy. The analysis of the magnetic properties is studied by electronic paramagnetic resonance (EPR). Simultaneously, compound (1) exhibits a potential inhibitory effect against the key enzymes associated with diabetes, obesity, and hyperlipidemia. It demonstrates IC50 values of 0.21 μM and 0.32 μM against α‐amylase and lipase, respectively. Consequently, it emerges as a promising candidate for the treatment of diabetes and obesity. [ABSTRACT FROM AUTHOR]

Here, we combined magnetometry, multi‐frequency electronic paramagnetic resonance, and wave function based ab initio calculations to investigate magnetic properties of two high spin Co(II) complexes Co(BDPRP) (BDPRP=2,6‐bis((2‐(S)‐di(4‐R)phenylhydroxylmethyl‐1‐pyrrolidi‐nyl)methyl)pyridine, R=H for 8; R=tBu for 9). Complexes 8 and 9 featuring effective D3h symmetry were found to possess D=24.0 and 32.0 cm−1, respectively, in their S=3/2 ground states of 1e''dxz/yz41e'dxy/x2-y221a1'dz21 ${{\left(1{{\rm e}}^{{\rm { {^\prime}}}{\rm { {^\prime}}}}\right({d}_{xz/yz}\left)\right)}^{4}{\left(1{{\rm e}}^{{\rm { {^\prime}}}}\right({d}_{{xy/{x}^{2}-y}^{2}}\left)\right)}^{2}{\left(1{{\rm a}}_{1}^{{\rm { {^\prime}}}}\right({d}_{{z}^{2}}\left)\right)}^{1}}$. Ligand field analyses revealed that the low‐lying d‐d excited states make either positive or vanishing contributions to D. Hence, total positive D values were measured for 8 and 9, as well as related D3h high spin Co(II) complexes. In contrast, negative D values are usually observed for C3v congeners. In‐depth analyses suggested that lowering symmetry from D3h to C3v induces orbital mixing between 1edxz/yz ${1{\rm e}\left({d}_{xz/yz}\right)}$ and 2edxy/x2-y2 ${2{\rm e}\left({d}_{{xy/{x}^{2}-y}^{2}}\right)}$ and admixes excited state 4A21e→2e ${{}^{4}{{\rm A}}_{2}\left(1e\to 2e\right)}$ into the ground state. Both factors turn the total D value progressively negative with the increasing distance (δ) of the Co(II) center out of the equatorial plane. Therefore, δ determines the sign and magnitude of final D values of five‐coordinate trigonal bipyramidal S=3/2 Co(II) complexes as measured for a series of such species with varying δ. [ABSTRACT FROM AUTHOR]

Halophyte species represent valuable reservoirs of natural antioxidants, and, among these, Salicornia europaea stands out as a promising edible plant. In this study, young and old S. europaea leaves were compared for the content of bioactive compounds and antioxidant activity to assess changes in different growth phases; then, the potential protective effects against low-dose CCl4-induced toxicant-associated fatty liver disease (TAFLD) were investigated by administering an aqueous suspension of young leaves to rats daily for two weeks. Quantification of total and individual phenolic compounds and in vitro antioxidant activity assays (DPPH, FRAP, and ORAC) showed the highest values in young leaves compared to mature ones. Salicornia treatment mitigated CCl4-induced hepatic oxidative stress, reducing lipid peroxidation and protein carbonyl levels, and preserving the decrease in glutathione levels. Electronic paramagnetic resonance (EPR) spectroscopy confirmed these results in the liver and evidenced free radicals increase prevention in the brain. Salicornia treatment also attenuated enzymatic disruptions in the liver's drug metabolizing system and Nrf2-dependent antioxidant enzymes. Furthermore, histopathological examination revealed reduced hepatic lipid accumulation and inflammation. Overall, this study highlights Salicornia's potential as a source of bioactive compounds with effective hepatoprotective properties capable to prevent TAFLD. [ABSTRACT FROM AUTHOR]

The measurement of partial pressures of oxygen (O2) and carbon dioxide (CO2) is fundamental for evaluating a patient's conditions in clinical practice. There are many ways to retrieve O2/CO2 partial pressures and concentrations. Arterial blood gas (ABG) analysis is the gold standard technique for such a purpose, but it is invasive, intermittent, and potentially painful. Among all the alternative methods for gas monitoring, non-invasive transcutaneous O2 and CO2 monitoring has been emerging since the 1970s, being able to overcome the main drawbacks of ABG analysis. Clark and Severinghaus electrodes enabled the breakthrough for transcutaneous O2 and CO2 monitoring, respectively, and in the last twenty years, many innovations have been introduced as alternatives to overcome their limitations. This review reports the most recent solutions for transcutaneous O2 and CO2 monitoring, with a particular consideration for wearable measurement systems. Luminescence-based electronic paramagnetic resonance and photoacoustic sensors are investigated. Optical sensors appear to be the most promising, giving fast and accurate measurements without the need for frequent calibrations and being suitable for integration into wearable measurement systems. [ABSTRACT FROM AUTHOR]

Two new pentagon‐embedded carbo[11]helicenes have been designed and synthesized in a three‐step process, which are the first example of carbo[11]helicenes through the post‐functionalization of twistacene. TD‐DFT analyses indicate that both of them possess high enantiomerization barriers of 42.29 kcal/mol and 40.76 kcal/mol, respectively. They emit strong red fluorescence and can be chemically oxidized into stable cationic radicals upon addition of AgSbF6 evidenced by the bathochromic‐shifted absorption spectra and the appearance of electronic paramagnetic resonance (EPR) signals. In addition, such helical derivatives can be chosen as radiative cooling materials in a glass model house, and the maxima of 5.4 °C for the former and 6.5 °C for the latter are found in the comparative tests, which might be caused by the NIR reflective response. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal encapsulated inside carbon aerogels were similar in physicochemical property. • The activity followed Co@CS>Fe@CS>Ni@CS>Zn@CS in heterogeneous EP. • Co@CS and Fe@CS exerted the superior activity for sole O 3 and H 2 O 2 decomposition. • The addition of M@CS enhanced the generation of · OH/ · O 2 −/1O 2 in EP. • M@CS/EP showed good applicability to various pollutants and real water. Transition metals have critical influences on the generation of reactive oxygen species in activating O 3 and H 2 O 2 , as the binary oxidant sources in electro-peroxone (EP). To evaluate the catalytic activity of different metals and reveal the reactive oxygen species generation in heterogeneous EP, series of metals encapsulated inside carbon aerogel spheres (M@CS, M=Fe, Co, Ni, Zn) were fabricated for strengthening EP. Atrazine was used as model pollutant due to its low reactivity with O 3 , and the abatement trends followed Co@CS > Fe@CS > Ni@CS > Zn@CS. Co@CS exhibited the superior catalytic activity with maximum metal active site utilization (1.28 × 103 min-1 mol-1 per mole Co atom sites at pH 7) and minimum electric energy consumption (0.106 kWh/m3-log). The catalytic activity of M@CS was related to the adsorption energies for O 3 and H 2 O 2 (Fe@CS > Co@CS > Ni@CS > Zn@CS) and the graphitization degree (Co@CS > Fe@CS > Ni@CS > Zn@CS). Verified by theoretical calculation and in-situ Fourier transformed infrared, the metal effectively promoted the adsorption and decomposition of O 3 and H 2 O 2 into the surface oxygen intermediates, finally generating · OH/ · O 2 -/1O 2. The carbon layer was conducive to the reduction of internal metal, ensuring catalyst durability. Electronic paramagnetic resonance and kinetic model revealed the occurrence, ratio and transient concentration of · OH/ · O 2 -/1O 2 in M@CS/EP. M@CS/EP showed good performance for pollutant removal in coexistence of anions, humic acid and real water. This study provides guidance for selecting the metal–carbon catalyst in heterogeneous EP. [ABSTRACT FROM AUTHOR]

The mechanism behind radiophotoluminescence (RPL) emission in Ag-doped alkali-phosphate glass remains unclear. To contribute to resolving this issue, the authors measured and analyzed the temporal change of electron spin/paramagnetic resonance (ESR) spectrum of a recently developed, weather-resistant RPL glass, named "SAPANS," after irradiation with X-rays. As a result, a continuous gradual increase in Ag2+-derived signals was observed even at four weeks post-irradiation, which corresponded well with the time build-up pattern of the RPL of SAPANS. In contrast, the signals derived from phosphorous-oxygen-hole centers (POHC) rapidly decreased over a few days. The peaks of Ag0 and Ag 2 + were not successfully separated from the ESR spectra because of the possible overlap of unidentified peaks, which implies a complex mechanism of RPL-center formation in Ag-doped alkali-phosphate glass that requires further investigation. • Temporal changes in the post-irradiation ESR spectrum of a recently developed RPL glass (SAPANS) were analyzed. • The Ag2+ signal gradually increased even at four weeks, which was similar to the time build-up pattern of RPL. • The signals from the phosphorus-oxygen-hole centers (POHC) sharply decreased over three days. [ABSTRACT FROM AUTHOR]

Human fingernails in combination with electron spin/paramagnetic resonance (ESR/EPR; hereafter "ESR") spectroscopy have high potential as an individual dosimetry tool in radiological accidents. For the practical realization of this technique, it is necessary to reduce the uncertainty due to the instability of ESR signals affected by both individual and environmental factors. In the present study, we examined the effects of different storage conditions (in a laboratory room, refrigerator, freezer, and vacuum) and prior sample treatment on the intensity and stability of ESR signals from the fingernails of a child, which has not been investigated in previous studies, in comparison with those of an adult. Fingernail samples collected from a 10 y/o female child and a 37 y/o male adult were irradiated with 160 kV X-rays at 10 Gy, and the time changes of radiation-induced ESR signal (RIS) and background signal (BKG) under different conditions were measured for up to 30 days. As results, the ESR signal intensities (peak-to-peak amplitudes) of both child and adult fingernails were the most stable under freezing conditions, while the intensities of both RIS and BKG of fingernails were notably higher and more stable in the child samples than in the adult samples. In addition, the child samples showed a better response to the prior treatment using ethanol and water; BKG faded significantly after treatment despite the original higher background. Further investigations with more samples from donors of different ages are needed to clarify and reduce inter- and intra-individual variability in the dosimetric properties of human fingernails. • The stability of ESR signals in child and adult fingernails was examined under four different storage conditions. • Freezing is preferred for long-term storage of fingernail samples. • Child fingernails showed a notable reduction in background ESR signals after treatment with ethanol and water. [ABSTRACT FROM AUTHOR]

• Double-vacancy-mediated S-scheme V O,S -Bi 2 WO 6 /CoIn 2 S 4 heterojunction was developed. • O, S double vacancies and S-scheme heterojunctions exhibited synergistic effect. • V O,S -Bi 2 WO 6 /CoIn 2 S 4 showed superior optical properties and degradation performance. • Degradation pathways of TC and CTC during co-existing degradation were proposed. • Toxicity of degradation intermediates of TC and CTC codegradation were analyzed. In this study, the V O,S -Bi 2 WO 6 /L-CoIn 2 S 4 heterojunction photocatalysts enriched with O and S double vacancies were prepared by L-cysteine self-doping strategy for efficient degradation of antibiotics. Results of X-ray photoelectron spectroscopy and electronic paramagnetic resonance (EPR) analysis demonstrated the existence of O and S vacancies in photocatalysts. Results of band structure analysis, electron spin resonance (ESR) and free radical capture experiments indicated that charges transfer pathway of the V O,S -Bi 2 WO 6 /L-CoIn 2 S 4 heterojunction conformed to S-scheme mechanism. Benefiting from the synergistic effects of O, S double defects, active sites of the heterojunction were increased, and separation of photogenerated carriers was promoted. The V O,S -Bi 2 WO 6 /L-CoIn 2 S 4 heterojunction achieved degradation efficiencies of 92.7%, 83.7%, and 40.7% for tetracycline (TC), Chlortetracycline (CTC), and Levofloxacin (LEV) within 100 min, respectively, with ·O 2 − as the dominated reactive species contributing to antibiotics degradation. The V O,S -Bi 2 WO 6 /L-CoIn 2 S 4 exhibited the highest kinetic constant, which was 1.73 and 1.33 times of those of the Bi 2 WO 6 and L-CoIn 2 S 4. Surprisingly, when TC and CTC were coexisted, the removal of TC decreased from 92.7% to 81%, while the removal of CTC increased to 88%, showing competitive effect. Possible degradation pathways of TC and CTC were proposed according to their degradation intermediates. Ecotoxicity of the main degradation intermediates were alomost lower than TC and CTC. This work provides a reference for developing efficient S-Scheme heterojunctions with dual-vacancy for efficient degradation of organic contaminants. [ABSTRACT FROM AUTHOR]