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Synthesis of Cyclic Carbonates from Alkenyl and Alkynyl Substrates

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Chinese Journal of Chemistry 2017年第5期35卷 541-550页

作者： Bo Zou changwen hu Key Laboratory of Cluster Science Ministry of Education of ChinaSchool of Chemistry and Chemical Engineering Beo'ing Institute of Technology Beo'ing 100081 China

As an extensively used chemical product,cyclic carbonate was generally synthesized by transesterification,or the cycloaddition of epoxides,diols with CO2.To reduce the production costs and expand the raw materials,alkenyl and alkynyl substrates have caused much attention in the synthesis of cyclic carbonates,such as olefins,allyl alcohols and propargylic alcohols.Based on the alkenyl substrate,the synthetic process involves a continuous reaction of oxidative carboxylation,with epoxide or halohydrin as an intermediate usually.Therefore,peroxides and nucleophiles （halogens or organic bases） are often necessary in the conversion.Using propargylic alcohols to produce a-alkylidene cyclic carbonates,noble metal catalysts play crucial roles in alkynyl activation,and organic bases are considered to assist the intramolecular and intermolecular proton transfer and combine CO2 molecular.As the carboxyl sources in products,inorganic carbonates and organic carboxylic acids also have some applications instead of CO2.In this review,we summarized the synthetic routes of cyclic carbonates from alkenyl and alkynyl substrates in the aspect of catalyst,mechanism and the development tendency.

关键词： cyclic carbonates CO2 conversion olefins propargylic alcohols

Magnetic properties of heteropolyoxometalates

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Chinese Science Bulletin 1999年第6期44卷 481-488页

作者： Lin Xu changwen hu Enbo Wang NE Normal Univ Dept Chem Changchun 130024 Peoples R China

The progress of the study on the magnetic properties of heteropolyoxometalates during the late decade is reviewed. Some anions of heteropolyoxometalates containing magnetic atoms, such as [M4（H2O）4(PW9O342]10- and [M4（H2O）4(P2W15O562]16-[M= Co（ Ⅱ ）, Zn（ Ⅱ ）, Cu（ Ⅱ ）, Mn（ Ⅱ ）,Ni（ Ⅱ ）], and [GaW9O37M3（H2O）3]n-[M= Fe（ Ⅲ ）, Cu（ Ⅱ ）, Co（ Ⅱ ）], showed ferromagnetic and antiferromagnetic properties. The combination of heteropoly anions and organic π-donor of TTF+ （tetrathiofulvalene cation） results in a variety of magnetic properties. Furthermore, there is an interaction between the inorganic and organic components. The electrocrystallization technique can prepare the organic-inorganic salts of this kind, which will become the new member of molecular magnetic materials.Heteropoly blue is a kind of the mixed-valence complexes and its reduction electrons can be delocalized over anionic framework. The further study on the magnetic properties of heteropolyoxometalates

关键词： heteropolyoxometalates magnetic properties progress.

H_(3)PMo_(12)O_(40)-catalyzed coupling of diarylmethanols with epoxides/diols/aldehydes toward polyaryl-substituted aldehydes

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Chinese Chemical Letters 2020年第12期31卷 3233-3236页

作者： Guoping Yang Yufeng Liu Ke Li Wei Liu Bing Yu changwen hu Key laboratory of Cluster Science of Ministry of Education.Beijing Key Laboratory of Photoelectronic/Elecrophotonic School of chemistry and Chemicad EngineeringBeijing Instirute of TechnologyBeijing 100081China Jiangxi Key Laboratory for Mass Spectrormetry and Instrunentation East China University of TechnologyNanchang 330013China Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou 450001China

A versatile heteropoly acid(H_(3)PMo_(12)O_(40))-catalyzed coupling of diarylmethanols with epoxides was established for the synthesis of polyaryl-substituted aldehydes.Furthermore,the catalytic system was also suitable for the reaction of diarylmethanols and diols/aldehydes.The application of such an earthabundant,readily accessible,and nontoxic catalyst provides a green approach for the construction of polyaryl-substituted aldehydes.

关键词： Polyoxometalates Diarylmethanols Epoxides Polysubstituted aldehydes Acid catalysis

三角形Au@TiO_(2)介孔催化剂可见光降解亚甲蓝

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无机化学学报 2024年第5期40卷 941-952页

作者：刘兵张黄韩洪亮胡长文张英磊北京首创生态环保集团股份有限公司北京100037 北京首创北科环境科技研究院有限公司北京100044 北京工业大学环境与能源工程学院北京100124 首都师范大学化学系北京100089 北京理工大学化学与化工学院北京102401

利用溶胶凝胶法制备出一种三角形Au@TiO_(2)核壳材料。经过水热晶化,该材料膨胀至300 nm,壳层TiO_(2)晶化为介孔锐钛矿相,但核心三角形Au颗粒的形貌保持不变。采用粉末X射线衍射(PXRD)、ζ电位、高分辨透射电子显微镜(HRTEM)、热重分析(... 详细信息

利用溶胶凝胶法制备出一种三角形Au@TiO_(2)核壳材料。经过水热晶化,该材料膨胀至300 nm,壳层TiO_(2)晶化为介孔锐钛矿相,但核心三角形Au颗粒的形貌保持不变。采用粉末X射线衍射(PXRD)、ζ电位、高分辨透射电子显微镜(HRTEM)、热重分析(TGA)、光致发光(PL)光谱、光电流(i-t)以及光催化降解技术,对样品的结构和性能进行了系统、详细的检测与分析。经过晶化处理的Au@TiO_(2)在可见光波段的光降解亚甲蓝性能比未晶化时有了显著的提升,1 mg·mL^(-1)Au@c-TiO_(2)可以在可见光照射1 h后实现对60 mg·L^(-1)亚甲蓝全降解。电子顺磁共振(EPR)测试表明·O_(2)^(-)和·OH两种自由基对光降解起到了很大作用。通过综合分析实验结果和时域有限差分(FDTD)分析,探究了催化反应的机理。

关键词：光降解二氧化钛三角形金颗粒可见光

Syntheses and lyotropic liquid crystal properties of a series of sandwich-type tungstoarsenates heteropoly compounds with As/W ratio of 4/30

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Chinese Science Bulletin 1999年第21期44卷 1964-1967页

作者： Rudan huang Lihua Bi Enbo Wang Baoli Fei Lin Xu changwen hu NE Normal Univ Dept Chem Changchun 130024 Peoples R China

A series of sandwich-type tungstoarsenates heteropoly compounds with As/W ratio of 4/30, Na16[As4W30M4(H2O)2O112]·XH2O (M = Zn,Cu,Co,Ni,Mn and Cd), have been synthesized for the first time and structurally characterized by elemental analysis, IR and 183W NMR spectra. The crystal structure of Na16[As4W30Cu4(H2O)2O112]·63H2O was determined to be a triclinic system, of P1 symmetry, a = 1.2721(3) nm, b = 2.451 6(5) nm, c = 2.6450(5) nm,

关键词： tungstoarsenate heteropoly compounds synthesis lyotropic liquid crystal.

Conformational dynamics in GPCR signaling by NMR

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Magnetic Resonance Letters 2022年第3期2卷 139-146页

作者： Yunfei hu changwen Jin Joint Laboratory of the National Centers for Magnetic Resonance in Wuhan and in Beijing Wuhan430071China Beijing Nuclear Magnetic Resonance Center College of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in WuhanKey Laboratory of Magnetic Resonance in Biological SystemsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan430071China

G-protein-coupled receptors(GPCRs)mediate a wide range of cellular responses to various ligands or stimuli,and are the most important drug targets associated with human diseases.While major advances in GPCR structural biology have greatly deepened our understanding of its activation mechanism,the highly complex changes in the structural dynamics of GPCRs during activation remain underdetermined and their links to physiological functions largely unknown.Solution nuclear magnetic resonance(NMR)spectroscopy is an essential technique that allows the characterization of protein structural dynamics at atomic level,and has been applied in the studies of GPCR structural-function relationship in the past decade.Herein,we summarize a few specific studies in which solution NMR methods were employed and provided novel insights into questions difficult to be addressed by other methods.

关键词： G-protein-coupled receptor(GPCR) Membrane protein Dynamics Nuclear magnetic resonance(NMR) Cell signaling

星状Au@TiO_(2)介孔催化剂光催化降解刃天青

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化工环保 2024年第3期44卷 432-440页

作者：刘兵刘智强张黄韩洪亮胡长文张英磊北京首创北科环境科技研究院有限公司北京100044 中国铁路北京局集团有限公司北京100860 北京工业大学环境与能源工程学院北京100124 首都师范大学化学系北京100089 北京理工大学化学与化工学院北京102401

采用溶胶-凝胶法制备了一种核壳材料星状Au@TiO_(2),对其进行了水热晶化处理,并运用多种技术手段进行了表征,考察了星状Au@TiO_(2)对溶液中刃天青的光催化降解性能,探讨了降解机理。表征结果显示:晶化处理后,核心星状Au的形貌未发生改变... 详细信息

采用溶胶-凝胶法制备了一种核壳材料星状Au@TiO_(2),对其进行了水热晶化处理,并运用多种技术手段进行了表征,考察了星状Au@TiO_(2)对溶液中刃天青的光催化降解性能,探讨了降解机理。表征结果显示:晶化处理后,核心星状Au的形貌未发生改变,壳层TiO_(2)由无定形转化为锐钛矿型。实验结果表明:晶化处理后,星状Au@TiO_(2)的光催化性能增强,在初始刃天青质量浓度6 mg/L、催化剂加入量1 g/L、暗反应30 min、氙灯(500 W)照射60 min的条件下,星状Au@TiO_(2)经4次循环实验后,刃天青去除率由99.2%逐渐降低至91.0%,表现出良好的重复使用性能;经4次循环使用后,星状Au@TiO_(2)的结构未发生明显变化,稳定性良好。星状Au@TiO_(2)光催化降解刃天青的机理为:在可见光照射下,星状Au会产生局域表面等离子共振(LSPR)效应,当热电子能量积累超过Au的功函数时,热电子就会迅速迁移到星状Au外层的TiO_(2)表面并参与还原反应,产生·O_(2)^(-);同时,TiO_(2)表面光生空穴会氧化吸附的水分子,产生·OH;刃天青在·O_(2)^(-)和·OH的作用下,被氧化降解。

关键词：光催化二氧化钛星状金可见光

Generation of ultrafast radially polarized pulses through chirp-assisted femtosecond optical parametric amplification

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Science China(Physics,Mechanics & Astronomy) 2022年第5期65卷 51-57页

作者： SaiSai hu JieFeng huang XinHao Ren changwen Xu ShiXiang Xu DianYuan Fan HaiZhe Zhong International Collaborative Laboratory of 2D Materials for Optoelectronic Science&Technology of Ministry of Education Institute of Microscale OptoelectronicsShenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

Radially polarized beams characterized by an axially symmetric polarization distribution can be sharply focused to produce strong longitudinal fields in the vicinity.Future applications of these beams will be facilitated by the availability of higher powers and shorter durations.Currently,the ultrafast radially polarized pulse is typically generated via wavefront reconstruction from conventional linearly polarized states.Achievable pulse duration and intensity limits are strictly dependent on extra-cavity optics.Herein,a chirp-assisted near-degenerate type-II parametric process is presented as a pulse-energy-scalable method of accessing ultrafast radially polarized pulses.In a proof-of-principle experiment,the broadband gain balance between the orthogonally polarized signal components was realized via controlling the chirp of the pump pulse.Through an analogous pulseduration transfer effect,the radially polarized signal inherited the temporal and spectral characteristics of the pump pulse and maintained the radial polarization state of each frequency component of the signal.With a shorter pump pulse,the generation of few-cycle radially polarized pulses should be achievable,which may facilitate a wide range of ultrafast applications such as vacuum electron acceleration and high-harmonic generation.

关键词： radially polarized beam optical parametric amplifier ultrafast lasers spectral broadening optical parametric phase

Long-term asymptomatic SARS-CoV-2 infection associated with deficiency on multiple immune cells

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Biosafety and Health 2022年第3期4卷 205-208页

作者： Gang He Xia Chuai Dan Liang Chunyu Chen Changzheng hu changwen Ke Bixia Ke Peilin Zhen huajun Zhang Jiangmen Central Hospital affiliated with Jiangmen Hospital of Sun Yat-Sen University Jiangmen 529000China Department of Pathogenic Biology Hebei Medical UniversityShijiazhuangHebei 050017China Guangdong Center for Disease Control and Prevention Guangzhou 511430China State Key Laboratory of Virology Wuhan Institute of VirologyCenter for Biosafety Mega-ScienceChinese Academy of SciencesWuhan 430071China

The immune responses and the function of immune cells among asymptomatic severe acute respiratory syndrome coronavirus 2(SARS‐CoV‐2)infection cases,especially in immuno‐compromised individuals,remain largely unknown.Here we present a case of asymptomatic SARS‐CoV‐2 infection that lasted for at least 67 days.The patient has administrated Thymalfasin as 1.6 mg per dose every other day from Day 45 to 70,plus 200 mg per dose Arbidol antiviral therapy three doses per day from Day 48 to 57.Throughout the infection,no anti‐SARS‐CoV‐2 specific IgM or IgG antibodies were detected.Instead,the patient showed either a low percentage or an absolute number of non‐classical monocytes,dendritic cells(DCs),CD4^(+)T cells,and regulatory T cells(Tregs),which may account for the clinical feature and absence of antibody response.This case may shed new light on the outbreak management related to control/prevention,treatment,and vaccination of SARS‐CoV‐2 and other virus infections in immunocompromised individuals.

关键词： SARS‐CoV‐2 COVID‐19 Asymptomatic infection Antibody response Immune cells