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Hyperbranched poly(ether amine)(hPEA)as novel backbone for amphiphilic one-component type-Ⅱ polymeric photoinitiators

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Chinese Chemical Letters 2018年第3期29卷 451-455页

作者： tiantian li Zhilong Su Hongjie Xu Xuesong Jiang Xiaodong Ma Jie Yin Shanghai Key Laboratory of Electrical Insulation and Thermal Ageing State Key Laboratory for Metal Matrix Composite MaterialsSchool of Chemistry &Chemical Engineering Shanghai jiao Tong University

To make photoinitiators （PI） to be polymeric and water-soluble is an effective approach to develop the high efficient photoinitiator systems with low-migration, low-toxic and environment-friend. We developed a series of novel amphiphilic hyperhranched polymeric photoinitiators （hPEA-TXs, and hPEA- BPs） by introducing thioxanthone （TX） or benzophenone （BP） moieties into the periphery of the hyperbranched poly（ether amine）（hPEA） comprised of the hydrophilic poly（ethylene oxide）（PEO） short chain and coinitiator amine moieties in the backbone. Compared with their water-soluble low-molecular weight analogues, the resulting hyperbranched polymeric photoinitiators hPEA101-TX, hPEA211-TX, hPEA101-BP and hPEA211-BP could be dissolved very well not only in many organic systems including acrylate monomers, but also in water with high solubility of 10 wt~. The photopolymerization kinetics of water-soluble monomer acrylamide （AM） and three hydrophobic multifunctional acrylate monomers initiated by these hyperbranched photoinitiators were investigated in detail by photo-differential scanning calorimetric （photo-DSC）. Both hPEA-TXs and hPEA-BPs can initiate photopolymerization of AM as efficiently as their low-molecular weight analogues MGA-TX and MGA-BP, respectively. The final double bond conversion （DBC） of oil-soluble monomer hexanediol diacrylate （HDDA） photoinitiated by these hyperbranched photoinitiators can reach as high as 99%. Especially for photopolymerization of multifunctional monomers initiated by these hyperbranched polymeric photoinitiators, the final DBC of trimethylolpropane triacrylate （TMPTA） and pentaerythritol tetraacrylate （PETTA） can reach 80% and 60%, respectively, which is much higher than that of low-molecular weight photoinitiators.

关键词： Hyperbranched poly(ether amine) Polymeric photoinitiator Amphiphilic Hydrogen-abstracting Photopolymerization

Recent advances in transition-metal-free C–H functionalization of imidazo[1,2-a]pyridines

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Green Synthesis and Catalysis 2022年第3期3卷 227-242页

作者： linlin Shi tiantian li Guang-Jian Mei Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China

Imidazo[1,2-a]pyridines are unique nitrogen-containing organic compounds with wide applications in pharma-ceuticals,natural products,material science and *** to their significant biological and synthetic value,the construction of imidazo[1,2-a]pyridine scaffolds has been a highly intriguing research topic,and substantial progress had been made in the past *** this review,we aim to summarize the current advances in direct C–H functionalization of imidazo[1,2-a]pyridines under transition-metal-free *** the selected examples,we focused on the design and catalytic cycle mechanism,as well as on representative outcomes and applications.

关键词： Imidazo[1,2-a]pyridines Transition metal-free Iodo-mediated Organocatalyst Oxidant-mediated Base-mediated Catalyst-free

Temperature-Modified Acute Effects of Ozone on Human Mortality-Beijing Municipality,Tianjin Municipality,Hebei Province,and Surrounding Areas,China,2013-2018

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China CDC weekly 2021年第45期3卷 964-968页

作者： Chen Chen Jing liu Wanying Shi tiantian li Xiaoming Shi China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina

Summary What is already known about this topic?Ozone(O_(3))is a weather-driven photochemical ambient pollutant,and its harm to human health may be affected by meteorological factors such as ***,there is conflicting ev... 详细信息

关键词： ozone ambient Modified

基于RNA测序技术鉴定和分析绒山羊毛囊不同生长期mRNA的可变剪接

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中国草食动物科学 2024年第4期44卷 1-7页

作者：李莹莹董华娇梁千千张洁李甜甜许赫马月辉韩吉龙杨敏石河子大学动物科技学院石河子832003 中国农业科学院北京畜牧兽医研究所北京100193

可变剪接(Alternative splicing,AS)是在转录后水平调控基因表达的一种重要方式。为挖掘调控绒山羊毛囊周期性生长相关的关键可变剪接,通过比较绒山羊绒毛不同生长时期的皮肤转录组数据,以P0.1为标准筛选差异的可变剪接,并进行功能分析... 详细信息

可变剪接(Alternative splicing,AS)是在转录后水平调控基因表达的一种重要方式。为挖掘调控绒山羊毛囊周期性生长相关的关键可变剪接,通过比较绒山羊绒毛不同生长时期的皮肤转录组数据,以P0.1为标准筛选差异的可变剪接,并进行功能分析。结果显示,转换期Ⅰ、Ⅱ、Ⅲ、Ⅳ中分别鉴定到1615、1667、1387和1522个差异可变剪接,分别对应了1202、1268、1073、1170个基因;这些基因主要富集于Notch、Hedgehog、mTOR、AMPK、PI3K-Akt、Wnt、TGF-β等与毛囊发育相关的信号通路;蛋白互作网络结合富集分析表明,Ctnnb1、Gsk3b、Tgfbr1、Vegfa、Gli1等基因产生的可变剪接可能参与调控毛囊周期性生长。综上可知,可变剪接在绒山羊毛囊周期性生长过程中普遍存在,且在不同发育阶段间存在差异;鉴定到调控绒山羊毛囊周期性生长发育相关的关键差异可变剪接基因及其重要信号通路。

关键词：绒山羊毛囊周期性生长可变剪接转录组测序

基于对苯二甲酸的MOFs对含氧阴离子的吸附及光降解研究

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化工新型材料 2024年第7期52卷 273-278页

作者：陈悦李田甜种仙娥池立欣钱俊峰张致慧常州大学石油化工学院江苏省绿色催化与技术重点实验室常州213164

以对苯二甲酸为配体与金属盐反应得到两个金属-有机框架材料Cd-MOF和UiO-66,通过X射线粉末衍射仪(XRD)、热分析仪(TG)以及氮气吸脱附对两种MOFs材料进行表征,测试材料的纯度、热稳定性以及多孔性。用所合成的材料进行吸附和光催化降解... 详细信息

以对苯二甲酸为配体与金属盐反应得到两个金属-有机框架材料Cd-MOF和UiO-66,通过X射线粉末衍射仪(XRD)、热分析仪(TG)以及氮气吸脱附对两种MOFs材料进行表征,测试材料的纯度、热稳定性以及多孔性。用所合成的材料进行吸附和光催化降解含氧阴离子实验。结果表明:Cd-MOF对MnO^(-)_(4)、Cr_(2)O_(7)^(2-)和CrO_(4)^(2-)的吸附率分别可以达到100%、57%、62%,经过光降解后的去除率可达到100%、84%、87%,UiO-66对MnO^(-)_(4)、Cr_(2)O_(7)^(2-)、CrO_(4)^(2-)的吸附率分别可以达到66%、25%、60%,经过光降解后的去除率可达到99%、40%、87%。相对于吸附能力,两种MOFs材料对含氧阴离子尤其是含Cr阴离子均表现出更好的光催化降解能力,Cd-MOF对含氧阴离子的去除率优于UiO-66。机理研究表明,在光催化降解过程中产生了活性物质·O^(-)_(2)和·OH,它们的产生有助于提高降解效率。

关键词：金属-有机框架材料含氧阴离子吸附光催化降解对苯二甲酸配体

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《高温热浪公众健康防护指南》解读

中华预防医学杂志 2024年第5期58卷 588-591页

作者：李湉湉陈晨张梦雪刘彦雯潘力军孙庆华刘园园张翼王林中国疾病预防控制中心环境与人群健康重点实验室中国疾病预防控制中心环境与健康相关产品安全所北京100021

近年来,高温热浪已对我国居民健康造成严重影响,我国对高温热浪公众健康防护指南有重要需求。国家疾病预防控制局组织专家充分调研全球及我国高温热浪人群健康流行病学研究证据,解析不同人群的健康危害及防护需求,提出切实有效的个体防... 详细信息

近年来,高温热浪已对我国居民健康造成严重影响,我国对高温热浪公众健康防护指南有重要需求。国家疾病预防控制局组织专家充分调研全球及我国高温热浪人群健康流行病学研究证据,解析不同人群的健康危害及防护需求,提出切实有效的个体防护措施及健康建议。基于此编制的《高温热浪公众健康防护指南》(简称《指南》)于2023年6月正式发布。本文围绕《指南》的制定背景与意义、编制原则、主要依据、核心内容、实施与推广等方面进行解读,以促进对《指南》内容理解、加强《指南》宣贯实施。

关键词：高温热浪健康防护指南

Metal-organic Chemical Vapor Deposition of GaSb/GaAs Quantum Dots： the Dependence of the Morphology on Growth Temperature and Vapour V/Ⅲ Ratio

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Chemical Research in Chinese Universities 2014年第1期30卷 13-17页

作者： YANG Haoyu liU Renjun LU You WANG liankai li tiantian li Guoxing ZHANG Yuantao ZHANG Baolin State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 P. R. China

GaSb quantum dots have been widely applied in optoelectronic devices due to its unique electrical and optical *** effects of metal-organic chemical vapor deposition（MOCVD） parameters,such as growth temperature and vapour V/Ⅲ ratio[V/Ⅲ ratio means the molar ratio of trimethylgallium（TMGa） and triethylantimony（TESb）],were systematically investigated to achieve GaSb quantum dots with high quality and high *** features of surface morphology of uncapped GaSb quantum dots were characterized by atomic force microscope（AFM） *** results show that the surface morphologies of quantum dots are strongly dependent on growth temperature and vapour V/Ⅲ *** quantum dots with an average height of 4.94 nm and a density of 2.45× 1010 cm-2 were obtained by optimizing growth temperature and V/Ⅲ ratio.

关键词： GaSb quantum dot Surface morphology Metal-organic chemical vapor deposition Atomic force microscope

Increased Mortality Risks from a Spectrum of Causes of Tropical Cyclone Exposure — China, 2013–2018

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China CDC weekly 2023年第6期5卷 119-124,I0001-I0007页

作者： Yuanyuan liu Meilin Yan Hang Du Qinghua Sun G.Brooke Anderson tiantian li China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina School of Ecology and Environment Beijing Technology and Business UniversityBeijingChina Department of Environmental&Radiological Health Sciences Colorado State UniversityFort CollinsCOUSA

What is already known about this topic?Tropical cyclone(TC)has a substantial and adverse impact on non-accidental ***,whether heterogeneity exists when examining deaths from subcauses and how TC impacts non-accidental mortality in the short term remain *** is added by this report?This study found substantial associations at lag 0 between TC exposure and circulatory and respiratory *** exposures were associated with increased risks for several mortality sub-causes at lag 0 day,including ischemic heart disease,myocardial infarction,cardiac arrest,cerebrovascular disease,stroke,chronic obstructive pulmonary disease,and Parkinson’s *** are the implications for public health practice?This finding suggests an urgent need to expand the public health focus of natural disaster management to include non-accidental mortality and sub-causes.

关键词： mortality disaster Tropical

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