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Chinese Journal of Chemistry 2023年第16期41卷 1987-1993页

作者： zhenwei chu Jinhua Li Dafa Chen Zhengyu Lu Weiran Meng Ming Luo Haiping Xia Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong 518055China

Comprehensive Summary Metallacyclopentadienes play a vital role in transition-metal mediated and catalyzed cycloaddition reactions of *** versatile reactions of metallacyclopentadienes with alkynes have been disclosed,[2+1]cycloadditions of metallacyclopentadienes and alkynes have never been *** present work,we report the formal[2+1]cycloadditions of a metallacyclopentadiene unit with a broad scope of commercial alkynes,providing a facile strategy to construct tetracyclic conjugated *** deuterated experiment indicates a metal vinylidene intermediate has been involved in[2+1]***,the electrophilic substitution reaction of the tetracyclic conjugated compound with the aid of density functional theory(DFT)calculated Fukui functions is investigated.

关键词： Metallacycle Cycloaddition Alkynes Electrophilic substitution Conjugation

Aromatic chloroosmacyclopentatrienes

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National Science Review 2023年第3期10卷 163-168页

作者： zhenwei chu Guomei He chuan Shi Yuhui Hua Yaxi Huang Jiangxi Chen Hujun Xie Guochen Jia Department of Materials Science and Engineering College of Materials Xiamen University Department of Chemistry The Hong Kong University of Science and Technology Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University Department of Applied Chemistry Zhejiang Gongshang University

Aromatic metallacycles are of considerable current *** aromatic metallacycles are mainly those with carbon,nitrogen,oxygen and *** this work,we report the synthesis and characterization of aromatic chloroosmacyclopentatrienes,which represent the first structurally confirmed metallaaromatic with a chlorine atom in its ***-crystal X-ray diffraction studies show that these planar chloroosmacyclopentatrienes possess a very short Os-CIC distance suggesting M=CIC bond character.

关键词： metallacycles chlorometallacyclopentatriene osmium o-ethynylphenyl alkynes halocarbon complex

In vitro bio-corrosion behaviors of biodegradable AZ31B magnesium alloy under static stresses of different forms and magnitudes

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Journal of Magnesium and Alloys 2023年第3期11卷 1043-1056页

作者： Linyuan Han zhenwei Zhang Jianwei Dai Xuan Li Jing Bai Zhihai Huang Chao Guo Feng Xue Chenglin chu School of Materials Science and Engineering Southeast UniversityNanjing 211189China Jiangsu Key Laboratory for Advanced Metallic Materials Southeast UniversityNanjing 211189China School of Materials Engineering Nanjing Institute of TechnologyNanjing 211189China Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing 211189China

Biomedical degradable materials would be subjected to different degrees and forms of static stress after being implanted in the human *** this work,the biocorrosion behaviors of AZ31B magnesium alloy under different stress forms with different magnitudes(20~150MPa)were *** was found that the corrosion behaviors at stressed conditions were severer than those at unstressed conditions and corrosion rates were obviously *** biocorrosion behaviors are more sensitive to the effects of tensile loads than to compressive loads.A biocorrosion numerical model on the degradation process of Mg alloy under static loads was *** corrosion current density(i_(corr))of Mg alloy and the applied static stress(σ)matches a linear relationship of ln i_(corr)~σwell during the early stage(within 24 hrs)while deviated gradually in the latter period of *** work could provide a guidance and theoretical reference for further researches on the biocorrosion behaviors and practical clinical applications of the biomedical materials subjected to physiological loads.

关键词： Magnesium alloy Biodegradable alloy Biocorrosion behavior Tensile loading Compressive loading

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The influence of alternating cyclic dynamic loads with different low frequencies on the bio-corrosion behaviors of AZ31B magnesium alloy in vitro

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Bioactive Materials 2022年第1期7卷 263-274页

作者： Linyuan Han zhenwei Zhang Jianwei Dai Xuan Li Jing Bai Zhihai Huang Chao Guo Feng Xue Chenglin chu School of Materials Science and Engineering Southeast UniversityNanjing211189JiangsuChina Jiangsu Key Laboratory for Advanced Metallic Materials Southeast UniversityNanjing211189JiangsuChina School of Materials Engineering Nanjing Institute of TechnologyNanjing211189JiangsuChina Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing211189China

The real physiological environment of human body is complicated with different degrees and forms of dynamic loads applied to implanted medical devices due to the daily activities of the patients,which would have impacts on the degradation behaviors of magnesium alloy *** this work,the bio-corrosion behaviors of AZ31B magnesium alloy under alternating cyclic dynamic loads with different low frequencies(0.1-2.5 Hz)were specially *** was found that the bio-degradation performances under external dynamic stressed conditions were much severer than those under unstressed conditions and static *** corrosion rates were generally accelerated as the rise of cyclic *** a numerical model for the degradation process of Mg alloy was *** corrosion current density icorr of Mg alloy and the applied loading frequency f matches a linear relationship of ln icorr∝f,which is the result of interactions between the cyclic alternating load and corrosive *** work could provide a theoretical reference and an experimental basis for further researches on the biodegradation behaviors of biomedical materials under dynamic conditions.

关键词： Magnesium alloy Biocorrosion Fatigue Frequency

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健康医疗一体机在老干部保健工作中的应用

中国老年保健医学 2011年第6期9卷 38-39页

作者：王瑞李萍吕晓娟陈渝鉏振伟第二炮兵总医院 100088 第二炮兵礼士路门诊部 100045 清华大学计算机系 100084

随着老干部对日常医疗保健关注程度的提高,干休所医疗保健需求也日益增加。健康医疗一体机主要是针对慢患者群而设计的医疗服务终端,可提供便捷、高效、交互程度较高的基础健康监测与反馈信息,对于节约干休所人力资源、满足老年干部人... 详细信息

随着老干部对日常医疗保健关注程度的提高,干休所医疗保健需求也日益增加。健康医疗一体机主要是针对慢患者群而设计的医疗服务终端,可提供便捷、高效、交互程度较高的基础健康监测与反馈信息,对于节约干休所人力资源、满足老年干部人群的基础健康保健需求具有十分重要的作用。

关键词：医疗保健一体机医疗保健

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连接底开裂原因分析及改进措施

金属加工（热加工） 2024年第8期 106-109页

作者：石燕杨有才褚小菲李恩省王翠英刘振威史林豫西工业集团河南北方红阳机电有限公司河南南阳474678

对失效连接底金相组织、化学成分、裂纹形态等进行理化检测,分析连接底裂纹产生的原因。结果表明:连接底裂纹为淬火裂纹;连接底中心圆柱部与底部过渡弧R角半径较小是主要原因,致使淬火过程中应力集中导致开裂;原材料中心部位组织疏松和... 详细信息

对失效连接底金相组织、化学成分、裂纹形态等进行理化检测,分析连接底裂纹产生的原因。结果表明:连接底裂纹为淬火裂纹;连接底中心圆柱部与底部过渡弧R角半径较小是主要原因,致使淬火过程中应力集中导致开裂;原材料中心部位组织疏松和冷却速度较快,进一步促进裂纹萌生;通过增大R角、调整热处理工艺来降低淬火应力,从而避免连接底淬火开裂的产生。

关键词：连接底淬火裂纹应力集中热处理工艺

Safety of endovascular therapy for symptomatic intracranial artery stenosis:a national prospective registry

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Stroke & Vascular Neurology 2022年第2期7卷 166-171页

作者： Yabing Wang Tao Wang Adam Andrew Dmytriw Kun Yang Liqun Jiao Huaizhang Shi Jie Lu Tianxiao Li Yujie Huang zhenwei Zhao Wei Wu Jieqing Wan Qinjian Sun Bo Hong Yongli Li Liyong Zhang Jianfeng chu Qiong Cheng Yiling Cai Pengfei Wang Qi Luo Hua Yang Baijing Dong Yang Zhang Jun Zhao Zuoquan Chen Wei Li Xiaoxin Bai Weiwen He Xueli Cai Maimai Ti Osama O Zaidat Department of Neurosurgery Xuanwu HospitalBeijingChina Neuroendovascular Program Massachusetts General HospitalBostonMassachusettsUSA Department of Evidence-Based Medicine Xuanwu HospitalBeijingChina Department of Neurosurgery First Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiangChina Department of Radiology Xuanwu HospitalBeijingChina Center of Neurointerventional Therapy Henan Provincial People's HospitalZhengzhouChina Department of Neurology Nanjing Drum Tower HospitalNanjingJiangsuChina Department of Neurosurgery Tangdu Hospital Fourth Military Medical UniversityXi'anShaanxiChina Department of Neurology Shandong University Qilu HospitalJinanShandongChina Department of Neurosurgery Shanghai Jiao Tong University School of Medicine Affiliated Renji HospitalShanghaiShanghaiChina Department of Neurology Shandong Provincial HospitalJinanShandongChina Neusurgery Changhai HospitalShanghaiChina Department of Neurosurgery Second Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiangChina Department of Neurosurgery Liaocheng People's HospitalLiaocheng CityShandongChina Department of Neurosurgery Jining First People's HospitalJiningShandongChina Department of Neurology Fujian Provincial HospitalFuzhouFujianChina Department of Neurology 306 Hospital of People's Liberation ArmyBeijingChina Department of Neurosurgery Tianjin Huanhu HospitalTianjinTianjinChina Department of Neurosurgery Jilin University First HospitalChangchunJilinChina Department of Neurology Affiliated Hospital of Guiyang Medical CollegeGuiyangGuizhouChina Department of Neurosurgery Fourth Affiliated Hospital of Harbin Medical UniversityHarbinHeilongjiangChina Department of Neurosurgery Peking University First HospitalBeijingBeijingChina Department of Neurology Liaocheng Second People's HospitalLiaochengChina Department of Neurology Shanghai Tenth People's HospitalShanghaiChina Department of Neurosurgery Tianjin Medical University General HospitalTianjinTianjin

Introduction The safety outcomes of endovascular therapy for intracranial artery stenosis in a real-world stetting are largely *** Clinical Registration Trial of Intracranial Stenting for Patients with Symptomatic Intracranial Artery Stenosis(CRTICAS)was a prospective,multicentre,real-world registry designed to assess these outcomes and the impact of centre *** 1140 severe,symptomatic intracranial arterial stenosis(ICAS)patients treated with endovascular therapy were included from 26 centres,further divided into three groups according to the annual centre volume of intracranial angioplasty and stent placement procedures over 2 years:(1)high volume for≥25 cases/year;(2)moderate volume for 10–25 cases/year and(3)low volume for<10 cases/*** The rate of 30-day stroke,transient ischaemic attack or death was 9.7%(111),with 5.4%,21.1%and 9.7%in high-volume,moderate-volume and low-volume centres,respectively(p<0.05).Multivariable logistic regression confirmed high-volume centres had a significantly lower primary endpoint compared with moderate-volume centres(OR=0.187,95%CI:0.056 to 0.627;p≤0.0001),while moderate-volume and low-volume centres showed no significant difference(p=0.8456).Conclusion Compared with the preceding randomised controlled trials,this real-world,prospective,multicentre registry shows a lower complication rate of endovascular treatment for symptomatic ***-uniform utilisation in endovascular technology,institutional experience and patient selection in different volumes of centres may have an impact on overall safety of this treatment.

关键词： intracranial prospective stenosis

基于模糊多属性决策方法的枢纽机场服务质量评价研究

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综合运输 2022年第9期44卷 45-52页

作者：褚衍昌黄世伟宋振伟中国民航大学经济与管理学院天津300300 中国民航大学交通科学与工程学院天津300300

本文从旅客登机流程入手分析枢纽机场服务质量影响因素,构建枢纽机场服务质量评价指标体系。引入语言分量的概念,建立基于模糊Topsis、模糊灰色关联度和模糊VIKOR方法的组合评价模型,对首都机场、虹桥机场、浦东机场、白云机场、双流机... 详细信息

本文从旅客登机流程入手分析枢纽机场服务质量影响因素,构建枢纽机场服务质量评价指标体系。引入语言分量的概念,建立基于模糊Topsis、模糊灰色关联度和模糊VIKOR方法的组合评价模型,对首都机场、虹桥机场、浦东机场、白云机场、双流机场五个枢纽机场的服务质量进行实证分析。结合评价指标体系中各指标的重要程度和评价结果,从中枢航线网络建设、周边交通管理等方面提出提升枢纽机场服务质量的建议。

关键词：枢纽机场服务质量评价三角模糊数语言分量多属性决策

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Combining quantitative and qualitative magnetic resonance imaging features to differentiate anorectal malignant melanoma from low rectal cancer

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Precision Clinical Medicine 2021年第2期4卷 119-128页

作者： Zeyan Xu Ke Zhao Lujun Han Pinxiong Li zhenwei Shi Xiaomei Huang chu Han Huihui Wang Minglei Chen Chen Liu Yanting Liang Suyun Li Yanqi Huang Xin Chen Changhong Liang Wuteng Cao Zaiyi Liu School of Medicine South China University of TechnologyGuangzhou 510006China Department of Radiology Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080China State Key Laboratory of Oncology in South China Collaborative Innovation Center of Cancer MedicineGuangzhou 510060China Department of Radiology Sun Yat-Sen University Cancer CenterGuangzhou 510060China Department of Radiology the Affiliated Hospital of Southwest Medical UniversityLuzhou 646000China The Second School of Clinical Medicine Southern Medical UniversityGuangzhou 510080China Shantou University Medical College Shantou 515041China Guangdong Cardiovascular Institute Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080China Department of Radiology Guangzhou First People’s Hospitalthe Second Affiliated Hospital of South China University of TechnologyGuangzhou 510180China Department of Radiology the Sixth Affiliated Hospital of Sun Yat-Sen UniversityGuangzhou 510655China

Background:Distinguishing anorectal malignant melanoma from low rectal cancer remains challenging because of the overlap of clinical symptoms and imaging *** aim to investigate whether combining quantitative and qualitative magnetic resonance imaging(MRI)features could differentiate anorectal malignant melanoma from low rectal ***:Thirty-seven anorectal malignant melanoma and 98 low rectal cancer patients who underwent preoperative rectal MRI from three hospitals were retrospectively *** patients were divided into the primary cohort(N=84)and validation cohort(N=51).Quantitative image analysiswas performed on T1-weighted(T1WI),T2-weighted(T2WI),and contrast-enhanced T1-weighted imaging(CE-T1WI).The subjective qualitative MRI findings were evaluated by two radiologists in *** analysis was performed using stepwise logistic *** discrimination performance was assessed by the area under the receiver operating characteristic curve(AUC)with a 95%confidence interval(CI).Results:The skewness derived from T2WI(T2WI-skewness)showed the best discrimination performance among the entire quantitative image features for differentiating anorectal malignant melanoma from low rectal cancer(primary cohort:AUC=0.852,95%CI 0.788–0.916;validation cohort:0.730,0.645–0.815).Multivariable analysis indicated that T2WI-skewness and the signal intensity of T1WI were independent factors,and incorporating both factors achieved good discrimination performance in two cohorts(primary cohort:AUC=0.913,95%CI 0.868–0.958;validation cohort:0.902,0.844–0.960).Conclusions:Incorporating T2WI-skewness and the signal intensity of T1WI achieved good performance for differentiating anorectal malignant melanoma from low rectal *** quantitative image analysis helps improve diagnostic accuracy.

关键词： anorectal malignant melanoma low rectal cancer magnetic resonance imaging quantitative image analysis

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振动圆盘类转子构件在流体中受到的作用力

振动工程学报 2004年第Z1期17卷 6-8页

作者：袁振伟褚福磊王三保清华大学精密仪器与机械学系北京100084 郑州大学化工学院郑州450002 清华大学精密仪器与机械学系北京100084 郑州大学化工学院郑州450002

依据流体力学的粘性阻力理论,以运动的转子构件为主体,利用矢量分析方法,导出了薄圆盘单独在流体中分别作平移和转角振动时受到的流体阻力解析表达式,并得到几点结论.这些公式可用于转子系统的流固耦合动力学有限元建模,同时对流体机械... 详细信息

依据流体力学的粘性阻力理论,以运动的转子构件为主体,利用矢量分析方法,导出了薄圆盘单独在流体中分别作平移和转角振动时受到的流体阻力解析表达式,并得到几点结论.这些公式可用于转子系统的流固耦合动力学有限元建模,同时对流体机械及潜液机械构件的动力学设计具有一定指导意义.

关键词：圆盘转子构件振动流体阻力