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Novel, Green, Simple and Uncatalyzed Route for High Yield Preparation of Benzaldehyde Glycol Acetal

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Chemical Research in Chinese Universities 2011年第5期27卷 799-802页

作者： TANG Jia SONG Ji-yuan WANG ge YANG mu GUO Wan-chun School of Material Science and Engineering University of Science and Technology Beijing Beij＇ing 100083 P. R. China

A simple approach for the condensation of benzaldehyde with ethylene glycol was adopted without employing any catalyst. The study reveals that factors including temperature, molar ratio of reactants, and the water removal significantly influence the conversion ratio of benzaldehyde. The results indicate that the use of optimal reaction conditions such as temperature and water removing exhibits more pronounced effects on the conversion ratio of benzaldehyde compared with the use of catalysts. In a word, a green and simple method for the condensation of aldehyde and menthandiol has been devised and investigated.

关键词： Condensation Benzaldehyde Ethylene glycol

Superconductivity at 10.4 K in a novel quasi-one-dimensional ternary molybdenum pnictide K2Mo3As3

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Science Bulletin 2018年第15期63卷 952-956页

作者： Qing-ge mu Bin-Bin Ruan Kang Zhao Bo-Jin Pan Tong Liu Lei Shan gen-Fu Chen Zhi-An Ren Institute of Physics and Beijing National Laboratory for Condensed Matter Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China

Here we report the discovery of the first ternary molybdenum pnictide based superconductor K2Mo3As3. Polycrystalline samples were synthesized by the conventional solid state reaction method. X-ray diffrac- tion analysis reveals a quasi-one-dimensional hexagonal crystal structure with （Mo3As3）2 linear chains separated by K^＋ ions, similar as previously reported K2Cr3As3, with the space group of P-6m2 （No. 187） and the refined lattice parameters a = 10.145（5） A and c = 4.453（8） A. Electrical resistivity, magnetic susceptibility, and heat capacity measurements exhibit bulk superconductivity with the onset Tc at 10.4 K in K2Mo3As3 which is higher than the isostructural Cr-based superconductors. Being the same group VIB transition elements and with similar structural motifs, these Cr and Mo based superconductors may share some common underlying origins for the occurrence of superconductivity and need more investigations to uncover the electron pairing within a quasi-one-dimensional chain structure.

关键词： Superconductivity K2Mo3As3 Quasi-one-dimensional Chevrel phase

Polycyclic aromatic hydrocarbon:environmental sources,associations with altered lung function and potential mechanisms

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Chinese Medical Journal 2020年第13期133卷 1603-1605页

作者： Li-Min Cao ge mu Wei-Hong Chen Department of Occupational&Environmental Health School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China Key Laboratory of Environment and Health Ministry of Education&Ministry of Environmental Protectionand State Key Laboratory of Environmental Health(Incubating)School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei 430030China

Polycyclic aromatic hydrocarbon(PAH)molecules are a large group of organic compounds with two or more fused benzene rings arranged in various confgurations."To date,hundreds of PAHs have been *** are widespread environmental contaminants formed as a result of incomplete combustion of carbonaceous materials in both natural and anthropogenic *** to the natural sources,such as volcanic eruptions and wild fires,anthropogenic sources,such as industrial processes,cigarette smoke,vehicular exhaust,residential heating fuels and charcoal-grilled and flame-broiled food,make a larger contribution to the generation of atmospheric PAHs.'Through inhalation,ingestion and dermal contract,PAHs from all sources can easily be absorbed in the body and further metabolized and excreted in *** urinary monohydroxylated PAH(OH-PAH)has been widely considered as a biomarker to represent individual PAH exposure levels in many studies.

关键词： process. aromatic incomplete

Discovery of a novel 112-type iron-pnictide and La-doping induced superconductivity in Eu_(1-x)La_xFeAs_2(x=0–0.15)

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Science Bulletin 2017年第3期62卷 218-221页

作者： Jia Yu Tong Liu Bo-Jin Pan Bin-Bin Ruan Xiao-Chuan Wang Qing-ge mu Kang Zhao gen-Fu Chen Zhi-An Ren Institute of Physics and Beijing National Laboratory for Condensed Matter Physics Chinese Academy of Sciences Beijing 100190 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100039 China

We report the discovery and characterization of a novel 112-type iron pnictide EuFeAs2, with La-doping induced superconductivity in a series of Eu1- xLaxFeAs2. The polycrystalline samples were synthesized through solid state reaction method only within a very narrow temperature window around 1073 K. Small single crystals were also grown from a flux method with the size about 100μm. The crystal structure was identified by single crystal X-ray diffraction analysis as a monoclinic structure with space group of P2 1/m. From resistivity and magnetic susceptibility measurements, we found that the parent compound EuFeAs2 shows distinct anomalies probably due to the Fe2＋ related antiferromagnetic/structural phase transition near 110K and the Eu2＋ related antiferromagnetic phase transition near 40K. La-doping suppressed both phase transitions to lower temperatures and induced superconducting transitions with a Tc - 11 K for Eu0.85La0.15FeAs2.

关键词： EuFeAs2 Superconductivity La-doping Antiferromagnetic transition

The dual effect of OxyR on cell response to ZnO Nanoparticles in E. coli

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The dual effect of OxyR on cell response to ZnO Nanoparticle...

Colloidal quantum-dot light emitting diodes with bias-tunable color

江苏省遗传学会第九次会员代表大会暨学术研讨会

作者： mu ge Lin Xiao State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University

The increasing use of zinc oxide nanoparticles（ZnO NPs） is likely to increase their release to the aquatic environment, and raises concerns about their environmental impacts. We explored the toxicity of ZnO NP using an oxidative stress sensitive E. coli mutant（△oxyR） and the wild type strain MG1655. Growth inhibition test revealed that the ZnO NPs displayed similar toxicity with Zn2+;however, bactericide tests revealed that the toxicity of ZnO NPs was higher than Zn2+ and the generation of reactive oxygen species（ROS） by ZnO NPs could be the main cause of toxicity under such low dissolution circumstance. The extracellular polymeric substances（EPS）, acting as a barrier, could protect E. coli against toxicity of ZnO NPs, but the formation of biofilm was more sensitive to ZnO NPs and Zn2+ toxicity than growth inhibition, indicating the function of cells was more sensitive to pollutant toxicity.

关键词： ZnO NPs E.coli △oxy R mutant ROS EPS

来源： cnki会议评论

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Photonics Research 2022年第7期10卷 1633-1639页

作者： ge mu TIANYU RAO MENGLU CHEN YIMEI TAN QUN HAO XIN TANG School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory for Precision Optoelectronic Measurement Instrument and Technology Beijing 100081China Yangtze Delta Region Academy of Beijing Institute of Technology Jiaxing 314019China

Although the performance of quantum-dot-based light emitting diodes(QLEDs)has been significantly enhanced over the past years,conventional full-color QLED displays still rely on the side-by-side pattern techniques of red(R)/green(G)/blue(B)quantum dots(QDs).Such lateral integration of multi-color pixels imposes technological difficulty in the development of high-resolution displays due to limited pixel density and fill ***,we demonstrate the development of full-color QLEDs with bias-tunable emission spectra by engineering mixed R/G/B QDs as light emitting *** Commission Internationale de l'Eclairage(CIE)chromaticity coordinates,QLEDs with bias-tunable color exhibit wide color variation ranging from red(0.649,0.330)to green(0.283,0.305)to blue(0.255,0.264)upon increasing voltages and can be tuned to emit white light(0.316,0.325).More importantly,the fabricated multi-color QLEDs show high luminance approaching 103cd m^(-2)and superior external quantum efficiency of 13.3%.Benefitting from the wide spectral tunability and light emitting efficiency,we believe the proposed multi-color QLEDs have great application prospects for both displays and lighting.

关键词： tunable diodes emitting

Superconductivity at 7.8 K in the ternary LaRu2As2 compound

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Science Bulletin 2016年第12期61卷 921-924页

作者： Qi Guo Bo-Jin Pan Jia Yu Bin-Bin Ruan Dong-Yun Chen Xiao-Chuan Wang Qing-ge mu gen-Fu Chen Zhi-An Ren Institute of Physics and Beijing National Laboratory for Condensed Matter Physics Chinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Quantum Matter Beijing 100190 China

Here we report the discovery of superconductivity in the ternary LaRu2As2 compound. The polycrystalline LaRu2As2 samples were synthesized by the conventional solid state reaction method. Powder X-ray diffraction analysis indicates that LaRu2As2 crystallizes in the ThCr2Si2-type crystal structure with the space group 14/ mmm （No. 139）, and the refined lattice parameters are a = 4.182（6）A and c = 10.590（3）A. The temperature dependent resistivity measurement shows a clear superconducting transition with the onset Tc （critical tempera- ture） at 7.8 K, and zero resistivity happens at 6.8 K. The upper critical field at zero temperature μ0Hc2（0） was estimated to be 1.6 T from the resistivity measurement. DC magnetic susceptibility measurement shows a bulk superconducting Meissner transition at 7.0 K, and the isothermal magnetization measurement indicates that LaRu2As2 is a type-II superconductor.

关键词： Superconductivity LaRu2As2 - Ternarycompound ThCr2Si2-type Magnetization Uppercritical field

Image of the Child Based on the Observation at UBC Child Care Service

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海外英语 2018年第10期 241-242页

作者：孙畅 DONG mu-ge CHEN Xuan-yu 北京航空航天大学 100083 Ningbo University Ningbo 315211China

Today our topic is Images of the Child:Teaching Methods,Teacher’s Role,and Notions of *** Malaguzzi said,"There are hundreds of different images of child."Children’s lives are lived through childhoods constructed for them by adult understandings of childhood and what children are and should *** have choices to make about who we think the child *** we are going to illustrate this topic based on the observation in UBC childcare *** this is our outline in 6 aspects.

关键词： Children UBC

稽留流产患者血液和绒毛中雌激素受体a基因多态性的表达

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中华医学杂志 2012年第9期92卷 616-619页

作者：刘芳其木格内蒙古医学院附属医院妇产科呼和浩特010059

目的通过研究绒毛与血清中雌激素受体a（ERa）基因多态性在稽留流产患者和正常妊娠者间分布的差异，分析ERa基因多态性与稽留流产病因之间的关系。方法选择100例稽留流产患者作为实验组，以同时期自愿选择人工流产术终止妊娠的正常早孕... 详细信息

目的通过研究绒毛与血清中雌激素受体a（ERa）基因多态性在稽留流产患者和正常妊娠者间分布的差异，分析ERa基因多态性与稽留流产病因之间的关系。方法选择100例稽留流产患者作为实验组，以同时期自愿选择人工流产术终止妊娠的正常早孕妇女102例作为对照组，取受试者空腹外周全血2ml及无菌条件下取得的绒毛组织。采用聚合酶链式反应一限制性片段长度多态性（PCR—RFLP）方法研究ERa基因的PvuⅡ和XbaI酶切多态性。并通过数据分析探讨ERa基因多态性分布与稽留流产之间的关系。结果血液、绒毛ERa基因PvuⅡ酶切等位基因P、P频率实验组与对照组比较差异有统计学意义（血液）（2=5．542，P〈0．05）（绒毛X。=7．559，P〈0．01），血液0R值：1．742；绒毛OR值：1．948。血液、绒毛ERa基因XbaI酶切等位基因X，X频率实验组与对照组比较差异有统计学意义（血液）（2=15．205，P〈0．01）（绒毛x2=13．750，P〈0．01），血液OR值：2．519，绒毛OR值：2．499。Kappa相关分析实验组P基因和X基因在血液和绒毛中表达均呈正相关。结论ERa基因多态性与稽留流产病因之间有关系，P、X等位基因可能是其发病易感基因。同时基因在血液和绒毛中表达的相关分析得出为正相关，基因检测可以用血液代替绒毛组织。

关键词：雌激素受体a 基因多态性稽留流产 Hardy—Weinberg遗传平衡定律