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Enantioselective reductive conjugate alkenylation ofα,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo Qiu-Quan Pan Qi-Wei Yao Xing-zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis,yet their asymmetric variant remains ***,asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–*** manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl *** method facilitates the enantioselective addition of keto alkenyl groups toα,β-enones,resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access *** use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

Posttraumatic stress symptoms among Chinese university students during the COVID-19 pandemic:Prevalence,correlates,and mental health help-seeking

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World Journal of Psychiatry 2025年第1期15卷 145-152页

作者： Rui-Yao Wu Lin-Feng Ge Bao-Liang zhong Department of Psychiatry The Affiliated Wuhan Mental Health CenterTongji Medical College of Huazhong University of Science&TechnologyWuhan 430012Hubei ProvinceChina Department of Psychiatry Wuhan Mental Health CenterWuhan 430012Hubei ProvinceChina

BACKGROUND Revisiting the epidemiology of posttraumatic stress symptoms(PTSSs)among university students during the coronavirus disease 2019(COVID-19)pandemic as well as understanding the mental health help-seeking behavior of individuals with PTSSs has critical implications for public mental health strategies in future medical *** To investigate the prevalence and correlates of PTSSs among university students during the first wave of the COVID-19 pandemic in China and to examine mental health help-seeking behaviors among these *** A total of 2507 Chinese university students were recruited via snowball *** students completed the Seven-item Screening Scale for Post-traumatic Stress Disorder during the first wave of the COVID-19 pandemic in ***-graphic characteristics,pandemic-related characteristics,and mental health help-seeking behaviors of students with PTSSs were also *** The prevalence of PTSSs among the participants was 28.0%.Seven significant correlates of PTSSs were identified(odds ratio=1.23-3.65,P≤0.024):Female sex,being 19 years old or older,living with others or alone,a low level of family economic status,fair or poor interpersonal relationships,severe or very severe local pandemic,and having family members diagnosed with ***,only 3.28%of the students with PTSSs reported seeking help from mental health *** the 23 students who sought help from mental health specialists,13 opted for online or telephone-based psychological *** Our data suggest that there was a high risk of PTSSs among university students and a high level of unmet mental health needs during the COVID-19 *** delivery of mental health services online or via telephone is a promising approach to address these unmet needs.

关键词： Posttraumatic stress symptoms University students COVID-19 Mental health help-seeking China

Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu zhong CAS Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of TechnologyHefei 230009China State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic MaterialsWuhan UniversityWuhan 430072China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601China Key Laboratory of Photochemical Conversion and Optoelectronic Materials&CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Photoactive complexes of nonprecious transition metals,mainly including those in the first-row and partially the second-row of the Periodic table of elements,have received increasing attention in view of their low cost and long-term *** are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices,artificial photosynthesis,photocatalysis,biodiagnostics,and therapeutics,*** review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes,including photoactive Zr,V,Cr,Mo,and W complexes,Mn complexes and hybrids,Fe,Co,Ni,and Cu complexes,and Zn and Cd complexes and hybrids.A particular focus is given on the molecular design,modulation of photophysical and photochemical properties,and applications of the representative and lately-developed nonprecious metal *** addition,a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

Sodium citrate enhancing electrodeposition of metallic arsenic from toxic trivalent arsenic and the mechanism understanding

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Journal of Environmental Sciences 2025年第5期151卷 79-87页

作者： Shuiping zhong Tingyu Xu Hang Chen Ding Tang Wen Tan Wei Weng Yanru Shi Zijin School of Geology and Mining Fuzhou UniversityFuzhou 350108China Fujian Key Laboratory of Green Extraction and High-value Utilization of New Energy Metals Fuzhou UniversityFuzhou 350108China Zijin Mining Group Co. Ltd.ShanghangLongyan 364200China Inner Mongolia Academy of Science and Technology Hohhot 010010China

Electrochemical conversion of hypertoxic trivalent arsenic to value-added metallic arsenic can not only contribute to pollution abatement,but also resources reutilization,therefore being widely *** reduction of trivalent arsenic as a promising way is widely ***,the high efficiency conversion is retarded by the sluggish reduction kinetics of AsO33−and fierce evolution of side products of both H_(2)and toxic AsH_(3).Herein,by using the sodium citrate as the additive,the current efficiency for metal arsenic production is increased greatly from 60%to 91%,with the accompanied evolution of hypertoxic AsH_(3)being restrained from 0.15 Nm^(3)/t_(As)to 0.022 Nm^(3)/t_(As),promising a high-efficiency and green *** electrochemical tests and electrode surface characterizations aswell as DFT calculations indicate that the added sodium citrate promotes both the diffusion of reactive AsO_(3)^(3−)towards the cathode and its subsequent adsorption on the Ti cathode,contributing to smoother reduction for generating metal arsenic,with the evolution of toxic AsH_(3)being hindered at the same *** results can provide new insights for the highefficiency and greener conversion of hypertoxic trivalent arsenic to value-added metallic arsenic.

关键词： Toxic arsenic Electrochemical conversion Metallic arsenic Sodium citrate

Thermal-flow-electric coupling performance analysis of a liquid-immersed battery thermal management system

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Science China(Technological Sciences) 2025年第1期68卷 153-172页

作者： Qiang GAO Jun TIAN Chujin BAO Yangfan zhong Chengbin ZHANG Yongping CHEN School of Energy and Environment Southeast UniversityNanjing 210096China Battery Testing Center China North Vehicle Research InstituteBeijing 100072China Zhejiang Immertech Co. Ltd.Hangzhou 310000China Alibaba Cloud Computing Co. Ltd.Shenzhen 518100China

Ensuring the safety and performance of lithium-ion batteries(LIBs)is a significant challenge for electric *** tackle this issue,an innovative liquid-immersed battery thermal management system(LIBTMS)using bionic baffles with fish-like perforations is *** thermal-flow-electric coupling characteristics of LIBTMSs with different baffle structures(no baffle,conventional baffle,baffle with circular perforations and baffle with fish-like perforations)are systematically investigated using experimental and numerical *** results indicate that the forced flow scheme exhibits better thermal management performance and voltage equalization than static ***,the LIB temperatures and voltage deviations of different LIBTMSs increase quickly with increasing discharge *** importantly,the innovative LIBTMS exhibits the best thermoelectric performance due to its excellent thermoelectric equilibrium behavior caused by high electrical and temperature consistency,as well as the best overall performance involving the balance between the pressure loss and heat transfer capacity of the *** with other structures,the innovative LIBTMS using baffles with fish-like perforations exhibits a maximum reduction of 10.1%,15.2%,25.8%and 9.0%in LIB maximum temperature,maximum temperature difference,system pressure drop and voltage deviation,respectively,under the same operating ***,for the LIBTMS using baffles with fish-like perforations,the bottom inlet and top outlet configuration and coolant precooling are suggested to enhance cooling performance.

关键词： baffle liquid-immersed thermoelectric performance lithium-ion battery battery thermal management

Unraveling the reaction mechanism of high reversible capacity CuP_(2)/C anode with native oxidation PO_(x) component for sodium-ion batteries

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Chinese Chemical Letters 2025年第1期36卷 574-578页

作者： Huixin Chen Chen Zhao Hongjun Yue Guiming zhong Xiang Han Liang Yin Ding Chen State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China CAS key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China College of Materials Science and Engineering Co-Innovation Center of Efficient Processing and Utilization of Forest ResourcesNanjing Forestry UniversityNanjing 210037China Laboratory of Advanced Spectro-electrochemistry and Li-ion Batteries Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Institute of Physics Chinese Academy of SciencesBeijing 100190China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi institutesChinese Academy of SciencesXiamen 361021China

Phosphorus-based anode is a promising anode for sodium-ion batteries(SIBs)due to its high specific capacity,however,suffers from poor electronic conductivity and unfavorable electrochemical *** metals such as copper(Cu)into phosphorus has been demonstrated to not only improve the electronic conductivity but also accommodate the volume change during cycling,yet the underline sodiation mechanism is not ***,take a copper phosphide and reduced graphene oxide(CuP_(2)/C)composite as an example,which delivers a high reversible capacity of>900 mAh/***,it is revealed that the native oxidation PO_(x)components of the CuP_(2)/C composite show higher electrochemical reversibility than the bulk Cu P_(2),based on a quantitative analysis of high-resolution solid-state^(31)P NMR,ex-situ XPS and synchrotron X-ray diffraction characterization *** sodiation products Na_(3)PO_(4) and Na_(4)P_(2)O_(7) derived from PO_(x) could react with Na-P alloys and regenerate to PO_(x) during charge process,which probably accounts for the high reversible capacity of the Cu P_(2)/C *** findings also illustrate that the phosphorus transforms into nanocrystalline Na_(3)P and Na_(x)P alloys,which laterally shows crystallization-amorphization evolution process during cycling.

关键词： CuP_(2)/C composite POx component Reaction mechanism Solid-state NMR Sodium-ion batteries

Development of a net ozone production rate detection system based on dual-channel cavity ring-down spectroscopy

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Journal of Environmental Sciences 2025年第3期149卷 419-430页

作者： Jinzhao Tong Renzhi Hu Changjin Hu Xiaoyan Liu Haotian Cai Chuan Lin Liujun zhong JiaweiWang Pinhua Xie School of Environmental Science and Optoelectronic Technology University of Science and Technology of ChinaHefei 230026China Anhui Institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China School of Pharmacy Anhui Medical UniversityHefei 230032China

A novel system for measuring net photochemical ozone production rates in the atmosphere based on cavity ring-down spectroscopy(OPR-CRDS)was *** system consists of two chambers(a reaction chamber and a reference chamber)and a dual-channel O_(x)-CRDS *** minimize the wall loss of O_(x)in the chambers,the inner surfaces of both chambers are coated with Teflon *** performance of the OPR-CRDS system was *** was found that even though the photolysis frequency(J value)decreased by 10%,the decrease in the P(O_(3))caused by the ultraviolet-blocking film coating was less than 3%.The two chambers had a good consistency in the mean residence time and the measurement of NO_(2)and O_(x)under the condition of no *** detection limit of the OPR-CRDS was determined to be 0.20 ppbv/*** further verify the accuracy of the system,the direct measurement values of the OPR-CRDS systemwere comparedwith the calculation results based on radical(OH,HO_(2),and RO_(2))reactions,and a good correlation was obtained between the measured and calculated ***,the developed instrument was applied to obtain the comprehensive field observations at an urban site in the Yangtze River Delta(China)for 40 days,the time series and change characteristics of the P(O_(3))were obtained directly,and the good environmental adaptability and stability of the OPR-CRDS system were *** is expected that the new instrument will be beneficial to investigations of the relationship between P(O_(3))and its precursors.

关键词： Ozone Net photochemical production rate CRDS Atmospheric chemistry

Efficient propane dehydrogenation catalyzed by Ru nanoparticles anchored on a porous nitrogen-doped carbon matrix

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Chinese Chemical Letters 2025年第2期36卷 230-233页

作者： Tianyi Yang Fangxi Su Dehuan Shi Shenghong zhong Yalin Guo Zhaohui Liu Jianfeng Huang State Key Laboratory of Coal Mine Disaster Dynamics and Control Institute of Advanced Interdisciplinary StudiesSchool of Chemistry and Chemical EngineeringChongqing University Key Laboratory of Advanced Materials Technologies International (HongKong Macao and Taiwan) Joint Laboratory on Advanced Materials TechnologiesCollege of Materials Science and EngineeringFuzhou University

Propane dehydrogenation （PDH） is a vital industrial process for producing propene,utilizing primarily Cr-based or Pt-based *** catalysts often suffer from challenges such as the toxicity of Cr,the high costs of noble metals like Pt,and deactivation issues due to sintering or coke formation at elevated *** introduce an exceptional Ru-based catalyst,Ru nanoparticles anchored on a nitrogendoped carbon matrix （Ru@NC）,which achieves a propane conversion rate of 32.2%and a propene selectivity of 93.1%at 550°C,with minimal coke deposition and a low deactivation rate of 0.0065 *** using techniques like TEM and XPS,along with carefully-designed controlled experiments,reveal that the notable performance of Ru@NC stems from the modified electronic state of Ru by nitrogen dopant and the microporous nature of the matrix,positioning it as a top contender among state-of-the-art PDH catalysts.

关键词： Electronic interaction Porous carbon matrix Propane dehydrogenation Ru nanoparticles Ru@NC

Multicomponent polymerization of elemental sulfur,difluoromethylene phosphobetaine and aryl silyl ethers toward aromatic poly(O,O′-monothiocarbonate)s

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Science China Chemistry 2025年

作者： Yongjiang Yu Rongrong Hu Ben zhong Tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates South China University of Technology School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong Kong AIE Institute

Polythiocarbonates with similar structures to polycarbonates, have emerged as a group of promising sulfur-containing polymers with a range of practical applications, taking advantages of their excellent optical properties, good thermal stability and filmforming ability, and so on. However, the synthesis of polythiocarbonates generally suffered from mixed isomeric structures of repeating units, and hazardous sulfur-containing reagents. In this work, an efficient multicomponent reaction of elemental sulfur,difluoromethylene phosphobetaine（PDFA）, and aryl silyl ethers was designed with the assistance of organic base 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene（MTBD） to produce 12 kinds of O,O′-monothiocarbonate compounds in up to 93% yields,taking advantages of the unique chemical property of difluorocarbene, and the deprotection of silyl group by F-generated from PDFA. Most importantly, the MTBD-assisted multicomponent polymerization of bis（aryl silyl ether）s, elemental sulfur, and PDFA was developed, affording 12 kinds of poly（O,O′-monothiocarbonate）s with well-defined structures, high Mws of up to16900 g/mol and high yields（up to 99%）. These poly（O,O′-monothiocarbonate）s possessed good film-forming properties and thermal stability, high light refractive indices and transmittance. The facile synthesis of these polymonothiocarbonates might pave the way for the development of promising sulfur-containing polymer materials.

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