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Chinese Chemical Letters 2020年第1期31卷 103-106页

作者： Qing-Song xu Chen Li Yong xu Defeng xu Mei-hua Shen hua-dong xu School of Pharmaceutical Engineering & Life Science Changzhou University

A ruthenium based catalytic system([Ru(p-cymene)Cl2]2/XantPhos with substoichiometric Cs2CO3)has been established to effectively achieve the first direct amination cyclization of 1,2,4-butanetriol with primary aromati... 详细信息

关键词： Amination cyclization N-Alkylation 1,2,4-Butanetriol 3-Pyrrolidinol Borrowing hydrogen Hydrogen autotransfer [Ru(p-cymene)Cl2]2

Rhodium catalyzed regioselective arene homologation of aryl urea via double C–H bond activation and migratory insertion of alkyne

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Chinese Chemical Letters 2017年第1期28卷 92-96页

作者： Yan Wang Hao Zhou Ke xu Mei-hua Shen hua-dong xu School of Pharmaceutical Engineering and Life Science Changzhou University Changzhou 213164 China

A convenient rhodium catalyzed oxidative arene homologation of aniline derivatives with symmetrical or unsymmetrical alkynes using Cu（OAc）2 as oxidant is described. Urea group is shown to be effective as a directing group for initial ortho C–H activation. Two migratory insertion events of alkyne into Rh–C bond occur successively, both with complete regioselectivity. This method is particularly useful for synthesis of polyarenes with different substituents, which has not been reported with conventional protocol. A mechanism has been proposed to explain the observed data.

关键词： Urea Directing group C-H Activation Arene homologation Asymmetric alkynes Oxidative cyclization

Copper catalyzed borylative cyclization of 3-arylallyl carbamoyl chloride with B_(2)pin_(2):stereoselective synthesis of cis-2-aryl-3-boryl-γ-lactams

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Chinese Chemical Letters 2021年第7期32卷 2297-2300页

作者： Mei-hua Shen Ting-Biao Wan Xiu-Rong huang Yan Li Dan-hua Qian hua-dong xu Defeng xu Jiangsu Key Laboratory of Advanced Catalytic Materials&Technology School of PharmacyChangzhou UniversityChangzhou 213164China

Borylative cyclization of E-3-arylallyl carbamoyl chlorides is achieved through copper catalyzed intramolecular carboboration with B_(2)pin_(2).2-Aryl-3-boryl-γ-lactams are formed with exclusive ***-Dppp combination ... 详细信息

关键词： Carboboration Borylative cyclization Copper catalysis Allyl carbamoyl chloride Borocupration γ-Lactam

Allylation and alkylation of oxindoleketimines via imine umpolung strategy

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Chinese Chemical Letters 2021年第7期32卷 2313-2316页

作者： Mei-hua Shen Chen Li Qing-Song xu Bin Guo Rui Wang Xiaoqian Liu hua-dong xu Defeng xu Jiangsu Key Laboratory of Advanced Catalytic Materials&Technology School of PharmacyChangzhou UniversityChangzhou 213164China

When treated with an alkoxide base like t-BuOK in aprotic solvent,N-di phenyl methyl imino oxindoles,made conveniently through condensation of corresponding isatins with N-di phenyl methyl amine,are deprotonated to form azaallyl *** and alkylation of this type of intermediates proceed smoothly with diverse *** work up finishes 3-amino-3-allyl/alkyl *** overall transformation equals to an umpolung process at the C3 of isatins.

关键词： Allylation Alkylation Azaallylaion Umpolung Oxindleketamine Spiro oxindole

One-pot synthesis of tetrahydroindoles via a copper catalyzed N-alkynation/[4+2] cycloaddition cascade

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Chinese Chemical Letters 2019年第1期30卷 266-268页

作者： Chun Jiang Piao-Piao Yu Qing Zhang hua-dong xu Mei-hua Shen School of Pharmaceutical Engineering & Life Science Changzhou University

A CuSO_4 catalyzed ynamide formation/[4+2] cycloaddition relay reaction was achieved in *** 4,7-cis-dihydroindolines were produced in good to high yields. The one-pot operation in conjunction with the cheap and benign... 详细信息

关键词： Tetrahydroindole N-Alkynation Intramolecular [4+2]cycloaddition Copper catalysis Ynamide Relay reaction

Experimental Study on Mixed-Mode(Ⅰ–Ⅱ)Fracture Toughness of Freshwater Ice

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Acta Mechanica Solida Sinica 2024年第2期37卷 252-264页

作者： Yaozhong xu Mao Zhou Xian Yi Wen hua Jiuzhou huang Wenyu Zhang Shiming dong Key Laboratory of Deep Underground Science and Engineering Ministry of EducationCollege of Architecture and EnvironmentSichuan UniversityChengdu610065China Failure Mechanics and Engineering Disaster Prevention Key Laboratory of Sichuan Province Sichuan UniversityChengdu610065China China Aerodynamics Research and Development Center/Low Speed Aerodynamics Research Institute Mianyang621000China College of Mechanical and Electrical Engineering Xichang UniversityXichang615000China

In recent years,the issue of aircraft icing has gained widespread *** breaking and detachment of dynamic ice can pose a threat to flight ***,the shedding and fracture mechanisms of dynamic ice are unclear and cannot meet the engineering needs of ice-shedding hazard ***,studying the fracture toughness of ice bodies has extremely important practical *** address this issue,this article uses a centrally cracked Brazilian disk(CCBD)specimen to measure the pure modeⅠtoughness and pure modeⅡfracture toughness of freshwater ice at different loading *** mixed-mode(Ⅰ–Ⅱ)fracture characteristics of ice are discussed,and the experimental results are compared and analyzed with the theoretical values of the generalized maximum tangential stress(GMTS)criterion considering the influence of *** results indicated that as the loading rate increases,the pure modeⅠtoughness and pure modeⅡfracture toughness of freshwater ice decrease,and the fracture toughness of freshwater ice is more sensitive to the loading rate.Ⅰn terms of fracture criteria,the theoretical value of the ratio of pure modeⅡfracture toughness to pure modeⅠfracture toughness based on the GMTS criterion is in good agreement with the experimental value,while the theoretical value based on the maximum tangential stress(MTS)criterion deviates significantly from the experimental value,indicating that the GMTS criterion considering the influence of T-stress can better predict the experimental results.

关键词： Freshwater ice Fracture criteria Centrally cracked Brazilian disk(CCBD) Mixed-mode(Ⅰ-Ⅱ) Loading rate

An Investigation of Oxidative DNA Damage in Pharmacy Technicians Exposed to Antineoplastic Drugs in Two Chinese Hospitals Using The Urinary 8-OHdG Assay

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Biomedical and Environmental Sciences 2012年第1期25卷 109-116页

作者： huaNG Yu Wen JIAN Le ZHANG Mei Bian ZHOU Quan YAN Xiao Feng hua xu dong ZHOU Ying HE Ji Liang The Second Affiliated Hospital of College of Medicine of Zhejiang University Hangzhou 310009 Zhejiang China School of Public Health Curtin Health Innovation Research Institute Curtin University of Technology Perth 6845 Australia Zhejiang Provincial Center for Disease Control and Prevention Hangzhou 310051 Zhejiang China Sir Run Run Shaw Hospital of College of Medicine of Zhejiang University Hangzhou 310020 Zhejiang China Zhejiang Provincial Hospital of Traditional Chinese Medicine Hangzhou 310012 Zhejiang China Zhejiang University Medical College Institute of Environmental Medicine Hangzhou 310058 Zhejiang China

Objective To investigate oxidative DNA damage in pharmacy technicians preparing antineoplastic drugs at the PIVAS （Pharmacy Intravenous Admixture Service） in two Chinese hospitals. Methods Urinary 8-OHdG served as a biomarker. 5-Fluorouracil （5-FU） concentrations in air, masks and gloves were determined. The spill exposure of each PIVAS technician to antineoplastic drugs was investigated. Eighty subjects were divided into exposed group t, II, and control group I, II. Results 5-FU concentration ratios for gloves and masks in exposed group I were significantly higher than those in exposed group II （P〈0.05 or P〈0.01）. The average urinary 8-OHdG concentrations in exposed group I, control group I, exposed group II, and control group II were 24.69＋0.93, 20.68＋1.07, 20.57＋0.55, and 12.96_＋0.73 ng/mg Cr, respectively. Urinary 8-OHdG concentration in exposed group I was significantly higher than that in control group I or that in exposed group 11 （P〈0.02）. There was a significant correlation between urinary 8-OHdG concentrations and spill frequencies per technician （P〈0.01）. Conclusion There was detectable oxidative DNA damage in PIVAS technicians exposed to antineoplastic drugs. This oxidative DNA damage may be associated with their spill exposure experience and contamination of their personal protective equipment.

关键词： Urinary 8-OHdG Oxidative DNA damage Antineoplastic drugs Occupational exposure Pharmacy Intravenous Admixture Service

Aldehyde oxidase mediated enantioselective metabolic health risk of dinotefuran

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Science China Chemistry 2024年第6期67卷 2079-2091页

作者： Liwei xu Xinxin xu hua Kuang Chuanlai xu Xiaoling Wu State Key Laboratory of Food Science and Resources Jiangnan UniversityWuxi214122China International Joint Research Laboratory for Biointerface and Biodetection and School of Food Science and Technology Jiangnan UniversityWuxi214122China Collaborative Innovation center of Food Safety and Quality Control in Jiangsu Province Jiangnan UniversityWuxi214122China

Chiral pollutants often pose significant differential environmental health *** this study,the biotransformation of chiral dinotefuran(DIN)and its enantioselective metabolic toxicity mechanisms have been systemically ***,reversedphase chromatography-high resolution mass spectrometry was developed to quantify the content of DIN R/S chiral enantiomer with pg level sensitivity,revealing a lower elimination rate constant(K_(e))of S-DIN(0.730 h^(-1))than R-DIN(0.746 h^(-1)).Secondly,the interaction mechanism between DIN metabolism and important endogenous bioactive molecules,such as aldehyde oxidase(AOX)and neurotransmitters,was *** DIN nitro-group was converted into a guanidine group by the reducing site of nearby flavin adenine dinucleotide(FAD)in AOX with the preferred higher affinity of ***,the endogenous tryptophan(Trp)aldehyde metabolic intermediate,5-hydroxyindoleacetaldehyde(5-HIAL),provides a persistent electron donor for DIN reduction via the oxidation-catalyzed site in AOX,resulting in remarkable up-regulation of monoamine neurotransmitters such as serotonin and ***,the higher level of neurotransmitters further mediated dysregulation of oxylipin homeostasis via the serotonergic pathway,where S-DIN exhibited more pronounced liver lipid damage and environmental health risk with the accumulated lipid biomarkers,oxidized triglyceride(OxTG)and oxidized sphingomyelin(OxSM).This study elucidates the AOX-mediated enantioselectivity metabolic pathway of DIN,providing a new analytical method for chiral pollutants and paves the way for their health risk assessments.

关键词： neonicotinoid dinotefuran enantiomer aldehyde oxidase metabolomics health risk

A General Simulation Method for Complex Deformation of Irregular-Shaped Origami Configurations

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Acta Mechanica Solida Sinica 2024年第1期37卷 90-98页

作者： Zhaochen dong Yichao Zhu xu Guo State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian 116023China

Most existing treatments for origami-folding simulations have focused on regular-shaped *** article aims to introduce a general strategy for simulating and analyzing the deformation process of irregular shapes by means of computational capabilities *** better simulate origami deformation with folding orders,the concept of plane follow-up is introduced to achieve automated computer simulation of complex folding patterns,thereby avoiding intersection and penetration between *** on the evaluation criteria such as the lowest storage energy with tightening and the fastest pace from tightening to unfolding,the optimal crease distribution patterns for four irregular(‘N’-,‘T’-,‘O’-,and‘P’-shaped)origami configurations are then presented under five *** the dimensions of the origami are fixed,it is discovered that simpler folding patterns lead to faster deformation of the origami *** the folding complexity is fixed,higher strain energy results in more rapid origami expansion.

关键词： Irregular-shaped origami Complex deformation Computer-aided origami design General simulation

Synergistic Impacts of Indian Ocean SST and Indo-China Peninsula Soil Moisture on the 2020 Record-breaking Mei-yu

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Advances in Atmospheric Sciences 2024年第9期41卷 1735-1750页

作者： Yinshuo dong Haishan CHEN xuan dong Wenjian hua Wenjun ZHANG Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China School of Atmospheric Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Bureau of Hydrology ChangJiang Water Resources CommissionWuhan 430010China

The Yangtze River basin(YRB)experienced a record-breaking mei-yu season in June‒July *** unique long-lasting extreme event and its origin have attracted considerable *** studies have suggested that the Indian Ocean(IO)SST forcing and soil moisture anomaly over the Indochina Peninsula(ICP)were responsible for this unexpected ***,the relative contributions of IO SST and ICP soil moisture to the 2020 mei-yu rainfall event,especially their linkage with atmospheric circulation changes,remain *** using observations and numerical simulations,this study examines the synergistic impacts of IO SST and ICP soil moisture on the extreme mei-yu in *** show that the prolonged dry soil moisture led to a warmer surface over the ICP in May under strong IO SST *** intensification of the warm condition further magnified the land thermal effects,which in turn facilitated the westward extension of the western North Pacific subtropical high(WNPSH)in June‒*** intensified WNPSH amplified the water vapor convergence and ascending motion over the YRB,thereby contributing to the 2020 *** contrast,the land thermal anomalies diminish during normal IO SST backgrounds due to the limited persistence of soil *** roles of IO SST and ICP soil moisture are verified and quantified using the Community Earth System *** synergistic impacts yield a notable 32%increase in YRB *** findings provide evidence for the combined influences of IO SST forcing and ICP soil moisture variability on the occurrence of the 2020 super mei-yu.

关键词： super mei-yu Indian Ocean SST soil moisture Indochina Peninsula