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Regioselectivity of Pd-catalyzed o-carboranearylation: a theoretical view

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Organic Chemistry Frontiers 2022年第6期9卷 1686-1695页

作者： Jiying Liu dongmin Fu Zitong Chen Tiantian Li Ling-Bo Qu Shi-Jun Li Wenjing Zhang Yu Lan Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhouHenan 450001China School of Chemistry and Chemical Engineering and Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 400030China

The mechanism and the regioselectivity of Pd-catalyzed B(4)–H arylation and B(4,5)–H diarylation foro-carborane with bidentate directing groups were investigated. The complete catalytic cycle involves Pdmediated concerted metalation–deprotonation, oxidative addition, counterion exchange, and reductiveelimination, where counterion exchange is critical. The reductive elimination is the rate- and regioselectivity-determining step for the whole catalytic cycle. B(3)-Arylation is unfavorable because the stericrepulsion between the substituent group on C(2) and the metal moiety would lead to significant distortionof o-carborane and would result in a higher activation energy for reductive elimination. The distortion ofo-carborane can be clearly observed from the change of its aromaticity in the corresponding transitionstates by the calculation of nucleus-independent chemical shifts. Moreover, counterion exchange withcarboxylate before reductive elimination significantly increases the positive charge of palladium, whichleads to a lower activation free energy for the sequential step.

关键词： elimination catalyzed reductive

HIV and syphilis infections among street-based female sex workers in China, 2010-2012

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Chinese Medical Journal 2014年第4期127卷 707-711页

作者： Li dongmin wang Lu Lin Wen Li Peilong wang Lan Guo Wei Ge Lin Ding Zhengwei Cui Yan wang Ning Division of Epidemiology National Center for Acquired Immune Definciency Syndrome/Sexually Transmitted Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing 102206 China Santa Clara County Public Health Department California 95126USA

Background Female sex workers （FSW） were high-risk population for HIV and other sexually transmitted diseases （STD） earlier,and now are an important driver of the HIV/AIDS epidemic in China.Sentinel surveillance for FSW was set up to monitor the trend of HIV prevalence and risk behavior-related HIV infection.This study collected the data on street-based FSW from HIV sentinel surveillance system to understand HIV and syphilis infections,risk behaviors,and intervention in China from 2010 to 2012.Methods The study population was the street-based FSW who were recruited for the national HIV integrated biological and behavioral surveillance between 2010 and 2012.Demographic information,HIV-related risk behaviors,and HIV and syphilis testing results were described and trend analysis was performed.Results Between 2010 and 2012,the number of street-based FSW surveyed was 3725,3425,and 3335,respectively.HIV knowledge awareness rate significantly increased from 74.6% in 2010 to 76.8% in 2011 and 82.2% in 2012 （P 〈0.01）.More FSW consistently used condom in the last month （49.0% in 2010; 51.0% in 2011; and 59.0% in 2012） and in the last commercial sex （72.0% in 2010; 78.5% in 2011; and 80.0% in 2012） over time.The proportions of individuals who received HIV testing in the last year were 31.2% （2010）,37.0% （2011）,and 36.9% （2012）（P-trend 〈0.01）.HIV prevalence rate changed from 1.5% in 2010 to 1.4% in 2011 and 2.3% in 2012 （P-trend=0.01）.Syphilis prevalence rate was 6.9%,7.2%,and 7.1% in the same period.The top three provinces with the highest average HIV prevalence rates over the 3 years were Guangxi （5.9%）,Yunnan （4.2%）,and Sichuan （1.2%）.Conclusions Street-based FSW are at high risk of HIV and syphilis infections.Intervention efforts need to target streetbased FSW who are of old age and minority,who use illicit drugs and have syphilis infection.

关键词： street-based female sex worker HIV syphilis prevalence risk behaviors

基于熵值模糊层次分析法的碳化硅负荷接入位置对电网影响评估

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电力需求侧管理 2024年第2期26卷 41-48页

作者：李德智龚桃荣吴俊涛宫建锋于东民需求侧多能互补优化与供需互动技术北京市重点实验室(中国电力科学研究院有限公司) 北京100192 南昌大学南昌330031 国网宁夏电力有限公司经济技术研究院银川750004

高载能负荷参与需求侧响应已成为促进新能源消纳的重要举措,未来新型电力系统面临新能源占比不断提高及高载能负荷大规模接入的情况。亟需研究高载能负荷大规模接入对电网影响,以合理规划新能源机组与高载能负荷在配电网中的位置与容量... 详细信息

高载能负荷参与需求侧响应已成为促进新能源消纳的重要举措,未来新型电力系统面临新能源占比不断提高及高载能负荷大规模接入的情况。亟需研究高载能负荷大规模接入对电网影响,以合理规划新能源机组与高载能负荷在配电网中的位置与容量。为此,以碳化硅负荷为研究对象,基于Matlab/Simulink仿真平台构建含高比例风电的IEEE33节点系统。基于参数摄动法,从电能质量、技术经济性、安全性3个方面评估风电机组与碳化硅负荷不同接入位置对电网的影响。应用熵值模糊层次分析法对仿真结果进行综合评估;评估结果与理论分析一致,验证了熵值模糊层次分析法的有效性。

关键词：熵值模糊层次分析法高载能负荷接入电网影响指标体系综合评价

Preparation of MCM-41-supported chiral Salen Mn (III) catalysts and their catalytic properties in the asymmetric epoxidation of olefins

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Chinese Science Bulletin 2007年第17期52卷 2337-2344页

作者： ZHAO dongmin ZHAO JiQuant ZHAO ShanShan HE LeQin wang WeiYu School of Chemical Engineering Hebei University of Technology Tianjin 300130 China

A secondary amino-modified mesoporous molecular sieve MCM-41 was obtained by reaction of bis(3-(triethoxysilyl)propyl)amine with MCM-41. The chiral Salen-Mn (III) complex was anchored onto the modified MCM-41 by a multi-step grafting method and two heterogenized catalysts with different Mn contents were obtained. The catalysts were characterized by XRD, N2 adsorption, ICP, FT-IR and DR UV-Vis. Their catalysis on asymmetric epoxidation of several olefins was studied with NaClO and m-CPBA as oxidants respectively. It was found that both the activity and enantioselectivity of the cata- lysts decreased after the homogeneous catalyst was heterogenized. The reasons resulting in the de- crease of catalytic performance were discussed.

关键词：分子筛 MCM-41 不对称环氧化作用 α-甲基苯乙烯锰手性化合物

Progress Towards the 90-90-90 Targets for Controlling HIV --China, 2018

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China CDC weekly 2019年第1期1卷 4-7页

作者： Yan Zhao Mengjie Han Ye Ma dongmin Li National Center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina.

What is already known about this topic?Since the Joint United Nations Programme on HIV and AIDS(UNAIDS)announced the 90-90-90 targets to control the global HIV epidemic in 2014,many countries have undertaken innovative measures to achieve this goal.The National Center for AIDS/STD Control and Prevention(NCAIDS)of China CDC convenes experts annually to evaluate the national progress towards these indicators.The most recent progress of 90-90-90 targets in China has not been previously published.What is added by this report?At the end of 2018,the percentage of living with HIV(PLWH)who had received a confirmed HIV diagnosis in China was 68.9%(61.5%-78.3%).The antiretroviral treatment coverage of diagnosed PLWH was 83.4%,and among patients on treatment for at least 12 months,94.2%achieved viral suppression.This provides most recent progress of 90-90-90 target in China.What are the implications for public health practice?China has made significant strides in curbing the HIV epidemic,but analysis on progress for the first 90 target for HIV testing remains out of reach.Innovative testing strategies may need to be developed to ensure that more PLWH can be identified.

关键词： diagnosis testing annually

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刘敞《先秦古器记》文献二种考论

美术研究 2023年第5期 25-32,41-45页

作者：王东民宁波大学潘天寿建筑与艺术设计学院 315211

以《先秦古器记》为名的刘敞文献有两种:一是现存于刘敞文集《公是集》中的记文;二是已佚的包含11件古器的图录,“记文”长久以来被视为“图录”的序言。然而,“记文”“图录”两种文献都存在疑点。在宋代文献中,仅见王应麟《玉海》及... 详细信息

以《先秦古器记》为名的刘敞文献有两种:一是现存于刘敞文集《公是集》中的记文;二是已佚的包含11件古器的图录,“记文”长久以来被视为“图录”的序言。然而,“记文”“图录”两种文献都存在疑点。在宋代文献中,仅见王应麟《玉海》及薛尚功《历代钟鼎彝器款识法帖》对“图录”的具体内容有引用。通过这些引用内容来考察“图录”的文本,可发现明显的器目杂糅、文题不符情况,其内容为拼凑、篡改刘敞文集相关篇目而来。“记文”原本是皇祐时期刘敞在汴京为御府所藏古器所作的一篇文章,并非嘉祐时期在长安为私人藏器图录所作的序言。历史上流传的“图录”很可能为南宋时人移植、拼凑刘敞《公是集》中的“记文”及其他文章而成的一卷伪托之作,刘敞并未著过“图录”。刘敞《先秦古器记》的文献考辨,对于早期金石学的重要文本、相关史实,以及发展脉络的认识都有重要的意义。

关键词：刘敞《先秦古器记》文献考辨金石学

Comparison of Extractive Distillation and Pressure-Swing Distillation for Methanol and Acetonitrile Separation

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China Petroleum Processing & Petrochemical Technology 2020年第4期22卷 137-146页

作者： Han dongmin Chen Yanhong Department of Chemical Engineering Shengli CollegeChina University of PetroleumDongying257061

In the present work,a comparative study of the extractive distillation and pressure swing distillation for methanol-acetonitrile separation is performed for the first time.Different separation alternatives,including the conventional extractive distillation,the extractive distillation with vapor or liquid side-stream,the pressure-swing distillation with or without full heat integration,and the heat-pump assisted pressure-swing distillation are rigorously simulated and optimized based on the minimum total annual cost(TAC)via the sequential iterative strategy.The results show that TAC and CO2 emission of the new extractive distillation with vapor side-stream(Vapor-SED)are similar to those of the extractive distillation with liquid side-stream(Liquid-SED).Furthermore,the Vapor-SED and Liquid-SED can achieve 30.01%and 30.56%reduction in TAC and 23.32%and 23.49%reduction in CO2 emission,respectively,over the most competitive fully heat-integrated PSD configuration.Hence,the extractive distillation with vapor or liquid side-stream appears to be a better option economically and environmentally for the separation of methanol and acetonitrile.

关键词： azeotrope extractive distillation pressure swing distillation TAC methanol/acetonitrile

A Visualized Fusion Protein Based on Self-assembly Hydrophobin HGFI

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Chemical Research in Chinese Universities 2015年第5期31卷 781-786页

作者： ZHAO Liqiang LIU Jinyuan SONG dongmin wang Xiangxiang TAI Feifei XU Haijin QIAO Mingqiang Key Laboratory of Bioaetive Materials Ministry of Education College of Life Sciences Nankai University Tianjin 300071 P. R. China

Hydrophobins are a type be used to modify material surfaces of small amphipathic proteins with a and adsorb enzymes, antibodies and unique self-assembly property, which can even cells. In this study, a fusion protein consisting of hydrophobin HGFI and green fluorescent protein（GFP） was successfully obtained from Pichia patoris （P. pastoris）. Water contact angle（WCA） measurement proves that the wettability of the surfaces of different materials was changed. We further demonstrated the self-assembly ability of HGFI-GFP, which can be used to disperse the multi-walled carbon nanotubes（MWCNTs）. Finally, the adsorption of HGFI-GFP onto the surface of the tissue engineering material poly（ε-caprolactone）（PCL） was evaluated by detecting the fluorescence of the fusion protein itself. The resalt demonstrates that both the basic self-assembly activity of the HGFI domain and the functional activity of the GFP domain were still remained.

关键词： Self-assembly Hydrophobin Fusion protein Dispersion Modification

Frailty:Past,present,and future?

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Sports Medicine and Health Science 2021年第1期3卷 1-10页

作者： dongmin Kwak LaDora V.Thompson Division of Sport Science Hanyang UniversityAnsanSouth Korea Department of Physical Therapy and Athletic Training Boston UniversityBostonMAUSA

The prevalence of frailty across the world in older adults is increasing dramatically and having frailty places a person at increased risk for many adverse health outcomes,including impaired mobility,falls,hospitalizations,and mortality.Globally,the concept of frailty is gaining attention and the scientific field has made great strides in identifying and conceptually defining frailty through consensus conferences,in advancing the overall science of frailty by drawing on basic science discoveries including concepts surrounding the hallmarks of aging,resilience,and intrinsic capacities,and in identifying the many challenges faced by professionals within diverse clinical settings.Currently,it is thought that frailty is preventable,thus the identification of a person's degree of frailty is vital.Identification of frailty is achievable through widely used frailty screening tools,which are valid,reliable,and easy to use.Following the identification of a person's degree of frailty,targeted intervention strategies,such as physical activity programs must be implemented.In this perspective,we provide a historical perspective of the frailty field since the last quarter of the 20th century to present.We identify the proposed underlying patho-physiology of multiple physiological systems,including compromised homeostasis and resilience.Next,we outline the available screening tools for frailty with a physical performance assessment and highlight specific benefits of physical activity.Lastly,we discuss current scientific evidence supporting the physical activity rec-ommendations for the aging population and for older adults with frailty.The goal is to emphasize early detection of frailty and stress the value of physical activity.

关键词： Frailty phenotype Intrinsic capacity Physical activity guidelines Multicomponent physical activity programs 2018 PAGAC Scientific Report