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Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu chen Jie li chen Zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai 200240China

We report a novel cyano migration-mediated radical-polar crossover process,whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently *** transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic *** studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution,leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Towards a blank design method for manufacturing big-tapered profiled ring disk by spinning-rolling process

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Chinese Journal of Aeronautics 2025年第1期38卷 70-86页

作者： Xuechao li lianggang GUO Xiaoqing chen Heng li State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China School of Materials Science and Engineering Xinjiang UniversityUrumqi 830017China National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China CNPC Baoji Oilfield Machinery Co. LtdBaoji 721000China

The big-tapered profiled ring disk is a key component of engines for rockets and missiles.A new forming technology,as called spinning-rolling process,has been proposed previously for the high performance,high efficiency and low-cost manufacturing of the *** design is the key part of plastic forming process *** spinning-rolling process,the shape and size of the blank play a crucial role in process stability,deformation behavior and dimensional *** this work proposes a blank design method to determine the geometry structure and sizes of the *** mathematical model for calculating the blank size has been deduced based on volume conservation and neutral layer length invariance *** FE simulation and corresponding trial production of an actual big-tapered profiled ring disk show that the proposed blank design method is *** order to obtain a preferred blank,the influence rules of blank size determined by different deformation degrees(rolling ratio k)on the spinning-rolling process are revealed by comprehensive FE *** considering the process stability,circularity of the deformed ring disk and forming forces,a reasonable range of deformation degree(rolling ratio k)is recommended for the blank design of the new spinning-rolling process.

关键词： Blank design method Spinning-rolling process Big-tapered profiled ring disk Rolling ratio Intelligent FE simulation

Forming solid electrolyte interphase in situ in an ionic conducting li_(1.5)Al_(0.5)Ge_(1.5)(PO_4)_3-polypropylene(PP) based separator for li-ion batteries

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Chinese Physics B 2016年第7期25卷 103-107页

作者：吴娇杨凌仕刚杨琪李泓许晓雄陈立泉 Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Ningbo Institute of Material Technology Engineering Chinese Academy of Sciences

A new concept of forming solid electrolyte interphases（SEI） in situ in an ionic conducting li（1.5）Al（0.5）Ge（1.5）（PO4）3-polypropylene（LAGP-PP） based separator during charging and discharging is proposed and demonstrated. This unique structure shows a high ionic conductivity, low interface resistance with electrode, and can suppress the growth of lithium dendrite. The features of forming the SEI in situ are investigated by scanning electron microscopy（SEM） and x-ray photoelectron spectroscopy（XPS）. The results confirm that SEI films mainly consist of lithium fluoride and carbonates with various alkyl contents. The cell assembled by using the LAGP-coated separator demonstrates a good cycling performance even at high charging rates, and the lithium dendrites were not observed on the lithium metal electrode. Therefore, the SEI-LAGP-PP separator can be used as a promising flexible solid electrolyte for solid state lithium batteries.

关键词： solid state lithium batteries solid electrolyte interphase ionic conductor coated separator lithium dendrite

Deciphering environmental factors influencing phytoplankton community structure in a polluted urban river

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Journal of Environmental Sciences 2025年第2期148卷 375-386页

作者： Xiaxia li Kai chen Chao Wang Tianyu Zhuo Hongtao li Yong Wu Xiaohui Lei Ming li Bin chen Beibei Chai School of Water Conservancy and Hydroelectric Power Hebei University of EngineeringHandan 056038China Collaborative Innovation Center for Intelligent Regulation and Comprehensive Management of Water Resources School of Water Conservancy and HydroelectricHebei University of EngineeringHandan 056038China Hebei Key Laboratory of Intelligent Water Conservancy Hebei University of EngineeringHandan 056038China Tianjin Water Group Binhai Water Co. Ltd.Tianjin 300308China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China School of Architecture and Civil Engineering Xi’an University of Science and TechnologyXi’an 710054China chengdu University of Technology Chengdu 610059China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing 100875China

Tuojiang River Basin is a first-class tributary of the upper reaches of the Yangtze River—which is the longest river in *** phytoplankton are sensitive indicators of trophic changes inwater bodies,characterizing phytoplankton communities and their growth influencing factors in polluted urban rivers can provide new ideas for pollution ***,we used direct microscopic count and environmental DNA(eDNA)metabarcoding methods to investigate phytoplankton community structure in Tuojiang River Basin(chengdu,Sichuan Province,China).The association between phytoplankton community structure and water environmental factors was evaluated by Mantel *** environmental monitoring data were used to pinpoint major factors that influenced phytoplankton growth based on structural equation *** the phylum level,the dominant phytoplankton taxa identified by the conventional microscopic method mainly belonged to Bacillariophyta,Chlorophyta,and Cyanophyta,in contrast with Chlorophyta,Dinophyceae,and Bacillariophyta identified by eDNA ***α-diversity analysis,eDNA metabarcoding detected greater species diversity and achieved higher precision than the microscopic *** growth was largely limited by phosphorus based on the nitrogen-to-phosphorus ratios>16:1 in all water *** analysis and structural equation modeling also confirmed that the nitrogen-to-phosphorus ratio was the principal factor influencing phytoplankton *** results could be useful for implementing comprehensive management of the river basin *** is recommended to control the discharge of point-and surface-source pollutants and the concentration of dissolved oxygen in areas with excessive nutrients(e.g.,Jianyang-Ziyang).Algae monitoring techniques and removal strategies should be improved in 201 Hospital,Hongrihe Bridge and Colmar Town areas.

关键词： Environmental DNA Microscopic count Phytoplankton growth Structural equation modeling Tuojiang River Basin

紫檀芪对中波紫外线照射的HaCaT细胞抗氧化物酶表达及活性的影响

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中华皮肤科杂志 2018年第4期51卷 274-278页

作者： Deng Huiyan, li Huaping, chen quan, li Runxiang, liang Bihua, Gao Aili, Zhou Xin, Zhu Huilan 510095 广州市皮肤病防治所皮肤科 10095 广州市皮肤病防治所皮肤科

目的探讨紫檀芪对HaCaT细胞急性中波紫外线（UVB）损伤的防御作用及相关机制。方法 MTS法和流式细胞仪检测不同浓度紫檀芪作用后HaCaT细胞增殖活性及凋亡与坏死率，筛选无毒性紫檀芪浓度。HaCaT细胞随机分为对照组（不做任何处理）、UV... 详细信息

目的探讨紫檀芪对HaCaT细胞急性中波紫外线（UVB）损伤的防御作用及相关机制。方法 MTS法和流式细胞仪检测不同浓度紫檀芪作用后HaCaT细胞增殖活性及凋亡与坏死率，筛选无毒性紫檀芪浓度。HaCaT细胞随机分为对照组（不做任何处理）、UVB组和2.44、4.88、9.75 μmol/L紫檀芪组及2.44、4.88、9.75 μmol/L紫檀芪＋ UVB组。Western印迹法检测紫檀芪和UVB处理前后HaCaT细胞内Nrf2核转位情况，定量PCR检测过氧化氢酶（CAT）和超氧化物歧化酶（SOD）的表达，EliSA检测CAT和SOD活性。结果 MTS法和流式细胞仪检测结果显示，2.44、4.88和9.75 μmol/L紫檀芪对HaCaT细胞无毒性作用。对照组Nrf2胞质蛋白1.03 ± 0.08、胞核蛋白1.04 ± 0.11；与对照组比较，2.44、4.88和9.75 μmol/L紫檀芪组Nrf2胞质蛋白和胞核蛋白均无明显变化，UVB组Nrf2胞质蛋白无明显变化，但Nrf2胞核蛋白显著增加（1.77 ± 0.08，q = 17.24，P 〈 0.01）。与对照组及UVB组比较，2.44、4.88和9.75 μmol/L紫檀芪＋ UVB组Nrf2胞质蛋白浓度均显著下降（0.86 ± 0.10、0.87 ± 0.11、0.46 ± 0.11，均P 〈 0.05），胞核蛋白浓度则显著升高（2.38 ± 0.11、2.57 ± 0.11、2.07 ± 0.13，均P 〈 0.01）。qPCR显示，与对照组相比，UVB照射对CAT mRNA表达有明显的抑制作用（P 〈 0.05），对SOD mRNA表达则无明显影响（P 〉 0.05），2.44、4.88和9.75 μmol/L紫檀芪组CAT和SOD的表达亦均无明显变化（P 〉 0.05）。然而，2.44、4.88、9.75 μmol/L紫檀芪可减轻UVB对CAT表达的抑制（P 〈 0.05），并上调SOD的表达（P 〈 0.05）。EliSA显示，UVB照射可显著降低HaCaT细胞内CAT和SOD活性（均P 〈 0.001），2.44、4.88、9.75 μmol/L紫檀芪可减轻UVB对CAT和SOD活性的抑制作用（P 〈 0.05），但其活性仍明显低于对照组（P 〈 0.05）。结论紫檀芪可通过激活Nrf2通路，上调其下游抗氧化物酶CAT、SOD表达，防御HaCaT细胞急性UVB损伤。

关键词：紫檀芪 HaCaT细胞 UVB Nrf2 抗氧化物酶

Timing of biomarker changes preceding Alzheimer's disease: for diagnosis, treatment or prevention?

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Science China life Sciences 2025年第2期68卷 575-577页

作者： Meina quan Innovation Center for Neurological Disorders and Department of Neurology Xuanwu HospitalCapital Medical University National Medical Center for Neurological Diseases and National Clinical Research Center for Geriatric Diseases Center of Alzheimer's Disease Beijing Institute of Brain DisordersCollaborative Innovation Center for Brain Disorders

The pathophysiological and behavioural features of Alzheimer's disease(AD) have been extensively investigated in transgenic mouse models, including the temporal sequence of each pathophysiological change and behavioural abnormality, a summary of which was recently presented by our team in this Journal(li et al.,2023). Nevertheless, studying such features and timings directly in human patients before symptoms occur is challenging.

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Soil colloids can significantly enhance spreading of polybromodiphenyl ethers in groundwater by serving as an effective carrier

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Journal of Environmental Sciences 2025年第1期147卷 93-100页

作者： lin Duan Min li Jiameng liu Wei chen College of Environmental Science and Engineering Ministry of Education Key Laboratory of Pollution Processes and Environmental CriteriaTianjin Key Laboratory of Environmental Remediation and Pollution ControlNankai UniversityTianjin 300350China

Polybromodiphenyl ethers(PBDEs),the widely used flame retardants,are common contaminants in surface soils at e-waste recycling *** association of PBDEs with soil colloids has been observed,indicating the potential risk to groundwater due to colloid-facilitated ***,the extent to which soil colloidsmay enhance the spreading of PBDEs in groundwater is largely ***,we report the co-transport of decabromodiphenyl ester(BDE-209)and soil colloids in saturated porous *** colloids released froma soil sample collected at an e-waste recycling site in Tianjin,China,contain high concentration of PBDEs,with BDE-209 being the most abundant conger(320±30 mg/kg).The colloids exhibit relatively high mobility in saturated sand columns,under conditions commonly observed in groundwater ***,under all the tested conditions(i.e.,varying flow velocity,pH,ionic species and ionic strength),the mass of eluted BDE-209 correlates linearly with that of eluted soil colloids,even though the mobility of the colloids varies markedly depending on the specific hydrodynamic and solution chemistry conditions ***,the mass of BDE-209 retained in the columns also correlates strongly with themass of retained ***,the PBDEs remain bound to soil colloids during transport in porous *** in this study indicate that soil colloidsmay significantly promote the transport of PBDEs in groundwater by serving as an effective *** might be the reason why the highly insoluble and adsorptive PBDEs are found in groundwater at some PBDE-contaminated sites.

关键词： Polybromodiphenyl ethers Soil colloids E-waste recycling sites Groundwater Facilitated transport

Research on the hazards of gas leakage and explosion in a full-scale residential building

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Defence Technology(防务技术) 2025年第1期43卷 168-181页

作者： chengjun Yue li chen Zhan li Bin Feng Ruizhi Xu Engineering Research Center of Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityNanjing 211189China

The gas explosion in residential building has always been a highly concerned *** in homogeneous mixtures have been extensively ***,mixtures are often inhomogeneous in the practical scenarios due to the differences in the densities of methane and *** order to investigate the effects of gas explosions in inhomogeneous mixtures,experimental studies involving gas leakage and explosion are conducted in a full-scale residential building to reproduce the process of gas *** fitting the dimensionless buoyancy as a function of dimensionless height and dimensionless time,a distribution model of gas in large-scale spaces is established,and the mechanism of inhomogeneous distribution of methane is also be ***,the stratified reconstruction method(SRM)is introduced for efficiently setting up inhomogeneous concentration fields in *** simulation results highlight that for the internal overpressure,the distribution of methane has no effect on the first overpressure peak(ΔP1),while it significantly influences the subsequent overpressure peak(ΔP2),and the maximum difference between the overpressure of homogeneous and inhomogeneous distribution is174.3%.Moreover,the initial concentration distribution also has a certain impact on the external overpressure.

关键词： Methane distribution Inhomogeneous mixture Gradient layer Gas explosion Explosive simulation

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H_(2)O_(2) synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye li Shuang Pan Yihuang chen Qiong liu College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou 325035ZhejiangChina Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology(China) Institute of AnalysisGuangdong Academy of Sciences(China National Analytical CenterGuangzhou)Guangzhou 510070GuangdongChina

Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production ***,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H_(2)O_(2)and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride(CNRb).The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h^(-1)for H_(2)O_(2)generation and photooxidation rate of 3.75 mM h^(-1)for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion(SCC)efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H_(2)O_(2)coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Photocatalytic H_(2)O_(2)synthesis Rubidium atom coordination Biomass valorization