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稀有金属材料与工程 2012年第S1期41卷 57-60页

作者： Wu, g. M. Tu, K. N. Kuo, C. C. Univ Calif Los Angeles Dept Mat Sci & Engn Los Angeles CA 90095 USA Chang gung Univ Inst Electroopt Engn Tao Yuan 333 Taiwan

High quality gaN epitaxy thin films have been desired for the energy-efficient,solid-state semiconductor illuminating *** substrates offer high crystal quality,low wafer cost,large wafer size,and potential integration with the well-established silicon processing ***,due to the large mismatch in lattice constants and thermal expansion coefficients,it is still challenging to grow high quality gaN on silicon *** this study,high quality gaN epitaxy has been engineering designed to grow on Si(111)substrate using varying gaN/AlgaN composite buffer structures by an Axitron 200 metal-organic vapor phase epitaxy deposition system.A thin AlN seed layer of 25 nm was firstly grown at 720℃.AlgaN layer of different thickness was then grown at 1050℃with subsequent gaN thin film until the total thickness reached 500 *** thickness of the subsequent gaN thin film could be increased by reducing the AlgaN thickness in the composite buffer *** results have shown that the lower gaN/AlgaN thickness ratio would decrease the dislocation density and provide crack-free,mirror-like upper gaN crystal thin *** the other hand,the gaN/AlgaN thickness ratio could be designed to be 2-6 to balance the processing cost and the thin film quality for engineering *** dislocation density has been about 2×10 9 *** addition,dislocation close loop was observed near the gaN/AlgaN *** annihilation mechanism could be depicted by the reduction in dislocation strain energy.

关键词： gallium nitride dislocation density silicon substrate buffer layer

Polyethylene glycol(PEg-400):An efficient and recyclable reaction medium for the synthesis of novel 1,5-benzodiazepines and their antimicrobial activity

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Chinese Chemical Letters 2011年第1期22卷 65-68页

作者： Shankaraiah g.Konda Baseer M.Shaikh Sanjay A.Chavan Bhaskar S.Dawane Organic Research Laboratory Department of Chemistry Yeshwant MahavidyalayaNanded-431602(M.S) India

A new series of imidazole-containing 1, 5-benzodiazepines have been synthesized by the condensation of chalcones with o- phenylenediamine using piperidine in polyethylene glycol （PEg-400） as an efficient and green reaction solvent. The advantages of this protocol are environmental friendliness, easy work-up, high yields, mild reaction condition and avoidance of expensive catalyst. Furthermore, newly synthesized compounds were evaluated for their antimicrobial activity.

关键词： PEg-400 Chalcones: o-Phenylenediamine 1 5-Benzodiazepines: Antimicrobial activity

Optical Switching of a Quantum Cascade Laser in Continuous Wave Operation

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Chinese Physics Letters 2010年第1期27卷 268-270页

作者： gang Chen Seong-wook Park I-Chun A. Chen Clyde g. Bethea Rainer Martini Department of Physics and Engineering Physics Stevens Institute of Technology Castle Point on Hudson Hoboken N3 07030 USA College of Optoelectronic Engineering Chongqing University Chongqing 400044

We demonstrate an optical switching in a middle infrared continuous-wave quantum cascade laser operated in single mode by illuminating its front facet with a near infrared laser. A decrease in the laser net gain is observed in the amplified spontaneous emission spectrum. This is attributed to an increase of the carrier concentration caused by the near infrared excitation. The net gain reduction allows the quantum cascade laser to be completely switched off from single mode lasing. This optical switching can be used to convert near infrared signals into middle infrared signals for free space communication.

关键词： Chinese climate network complex systems small world community

STRUCTURE IMPROVEMENT AND TEMPERATURE FIELD SIMULATION OF PREPARINg NANOPOWDER BY EVAPORATION-CONDENSATION METHOD

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Acta Metallurgica Sinica(English Letters) 2008年第3期21卷 178-182页

作者： J.S. Bao Y. Yin T.g. Liu Z.Y. Yang School of Mechanical and Electrical Engineering China University of Mining and Technology Xuzhou221116 China

A new apparatus, with a segregable conical water cooling condenser, which is heated by an electric arc using the evaporation-condensation method to prepare carbon-coated nanopowder, has been developed by the authors. Numerical simulation of the temperature field is done by the ANSYS software, and temperature in the reaction vessel is measured with the help of an experiment, to verify the simulation result. Influence of the temperature field in the reaction vessel, on the process of preparing nanopowder is then discussed simply. It is shown that the segregable conical water cooling condenser and carbon-coated surface process can be used to prepare steady carbon-coated metal nanopowder, at a lower cost and higher yield rate than the traditional structure. Simulation of the temperature field in the apparatus shows that the arc heating method can form a temperature field in the apparatus, which is quite favorable for nanopowder formation. Experiments show that the rational parameters using this apparatus, with the arc heating method to prepare carbon-coated nanopowder are electricity 60-100 A and arc length 5-8 mm.

关键词： Evaporation-condensation method Electric arc heating Temperature field Condenser structure

Assessment of nanocomposite photonic systems with the X-ray photoelectron spectroscopy

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Optoelectronics Letters 2007年第3期3卷 192-194页

作者： L. Minati g. Speranza M. Anderle M. Ferrari A. Chiasera g. C. Righini ITC-IRST Sommarive str. 18 38050 PovoItaly CNR-IFN CSMFO groupSommarive str. 1438050 Povo-TrentoItaly CNR Department of Materials and DevicesPiazzale A. Moro 700185 Romaand CNR IFAC50019 Sesto FiorentinoItaly

The chemical compositions of Ag-Er co-doped phosphate and silicate glasses were investigated with X-ray photoelectron spectroscopy with the purpose to identify the chemical state of silver. The analysis of the Ag 3d core lines show the presence of nanometer-sized silver particles in each of the annealed samples,even if these Ag 3d lines appear to be very different from each other. We explain these results as a different interaction of silver with the two glasses matrix,which leads to a different nucleation rate of the Ag clusters.

关键词：纳米复合光子系统评价 X线光电子光谱学磷酸盐玻璃硅酸盐玻璃 Ag-Er共掺杂

Nanoengineering of amino-functionalized mesoporous silica nanospheres as nanoreactors

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Progress in Natural Science:Materials International 2018年第2期28卷 242-245页

作者： Jinsuo gao Shouchun Wu Feng Tan Hao Tian Jian Liu g.Q.Max Lu Key Laboratory of Industrial Ecology and Environmental Engineering (MOE) School of Environmental Science and Technology Dalian University of Technology State Key Laboratory of Catalysis iChEM Dalian Institute of Chemical Physics Chinese Academy of Sciences Department of Chemical and Process Engineering and Advanced Technology Institute University of Surrey Vice-Chancellor's Office University of Surrey

Selective functionalization of mesoporous silica nanospheres（MSNs） is crucial for nanoengineering of ***, we have combined "surface-protected etching strategy" and "cationic surfactant assisted etching strategy" to prepare functionalized MSNs with externally attached amino groups. The externally attached NH;groups endow the catalysts with excellent catalytic performance for nitroaldol reaction between nitromethane and benzaldehyde. In addition, those NH;-MSNs can also be used to support gold nanoparticles, which display very good catalytic performance for reduction of 4-nitrophenol. It can be envisioned that the synthesis protocol developed in this work could also be extended to nanoengineered MSNs, which provides opportunities for nanoreactors design.

关键词： Mesoporous silica nanospheres Nanoengineering Nanoreactors Catalysis

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2BCM-6型茬地免耕播种机的研制

农业工程学报 2001年第3期17卷 174-176页

作者：王维新坎杂田学艳江英兰陈永成吴雪飞丛锦玲石河子大学机械电气工程学院新疆石河子832003

新疆无霜期短 ,为了实现一年两熟 ,改变传统的耕播方式 ,从而研制出 2 BCM- 6型茬地免耕播种机 ,实现了新疆麦茬地免耕覆盖播种油葵。主要介绍该机的组成、工作原理、主要部件设计 ,并对田间试验进行了研究分析。试验结果表明 :该机平... 详细信息

新疆无霜期短 ,为了实现一年两熟 ,改变传统的耕播方式 ,从而研制出 2 BCM- 6型茬地免耕播种机 ,实现了新疆麦茬地免耕覆盖播种油葵。主要介绍该机的组成、工作原理、主要部件设计 ,并对田间试验进行了研究分析。试验结果表明 :该机平均每穴粒数为 1.6 9粒 ,合格指数大于 98.7% ;穴长在 1～ 3cm内的占 99.3%以上 ;整机平均粒距为 19cm,变异系数小于 19.6 % ,粒距合格指数大于 94.9% ,重播指数小于 1.8% ,漏播指数小于 2 .9%。该机各项性能指标达到设计要求 ,并且较为稳定 ,工作可靠性较高。与传统耕播相比 ,可抢时播种 ,减少水分蒸发 ,减少径流 ,增加土壤的蓄水、保墒能力。

关键词：茬地免耕播种机单圆盘点种器设计

Bile acid formation in primary human hepatocytes

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World Journal of gastroenterology 2000年第4期6卷 522-525页

作者： Curt Einarsson Ewa Ellis Anna Abrahamsson Bo-gran Ericzon Ingemar Bjrkhem Magnus Axelson Division of gastroenterology and Hepatology Department of Medicine Department of Transplantation Surgery Department of Clinical Chemistry Karolinska Institutet at Huddinge University Hospital StockholmSweden Department of Clinical Chemistry Karolinska Institutet at Karolinska Hospital StockholmSweden

AIM To evaluate a culture system for bile acidformation in primary human hepatocytes incomparison with Hepg2 *** Hepatocytes were isolated fromnormal human liver tissue and were cultured inserum-free William’s E *** medium wascollected and renewed every 24 *** acids andtheir precursors in media were finally analysed bygas chromatography-mass *** Cholic acid(CA)andchenodeoxycholic acid(CDCA)conjugated withglycine or taurine accounted for 70% and 25% oftotal steroids.A third of CDCA was alsoconjugated with sulphuric *** thyroid hormone alone or in combination didnot significantly effect bile acid *** of cyclosporin A(10 μmol/L)inhibited thesynthesis of CA and CDCA by about 13% and30%,*** Isolated human hepatocytes inprimary culture behave as in the intact liver byconverting cholesterol to conjugated CA *** is in contrast to cultured Hepg2 cells,which release large amounts of bile acidprecursors and unconjugated bile acids into themedium.

关键词： bile acid formation cell culture cholesterol metabolism cyclosporin human hepatocytes

Environmental siblings of black agents of human chromoblastomycosis

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Fungal Diversity 2014年第2期65卷 47-63页

作者： V.A.Vicente M.J.Najafzadeh Jiufeng Sun R.R.gomes D.Robl S.g.Marques C.M.P.S.Azevedo g.S.de Hoog CBS-KNAW Fungal Biodiversity Centre P.O.Box 851673508AD UtrechtThe Netherlands Microbiology Parasitology and Pathology Post-graduation ProgramDepartment of Basic PathologyFederal University of ParanáCuritibaPRBrazil Institute for Biodiversity and Ecosystem Dynamics University of AmsterdamAmsterdamThe Netherlands Peking University Health Science Center Research Center for Medical MycologyBeijingChina Sun-Yat-sen Memorial Hospital Sun Yat-sen UniversityGuangzhouChina Second Medical Military University ShanghaiChina King Abdulassiz University Jeddah JeddahSaudi Arabia Department of Parasitology and Mycology and Cancer Molecular Pathology Research CenterGhaem HospitalSchool of MedicineMashhad University of Medical SciencesMashhadIran guangdong Provincial Institute of Public Health Guangdong Provincial Center for Disease Control and PreventionGuangzhouChina Federal University of Maranhão University Hospital of the Federal University of MaranhãoSão LuísBrazil Cedro Laboratory and University Hospital of the Federal University of Maranhão São LuísBrazil Institute of Biomedical Sciences University of São Paulo(USP)CEP 05508-900 São PauloBrazil

Agents of human chromoblastomycosis,a skin disease almost exclusively caused by members of the order Chaetothyriales,are assumed to be traumatically inoculated into the skin with sharp environmental materials such as plant thorns or wooden splinters carrying the respective *** the supposition that such fungi should have their main habitat in the environment,we investigated the occurrence of black fungi in living areas of patients with *** South America Fonsecaea agents are prevalent as agents of the disease,while also related Cladophialophora species,known from other types of skin infections,are known from the *** environmental isolates were preliminarily selected as possible agents of chromoblastomycosis,based on *** from ITS sequence data isolates were attributed to the genera Cladophialophora,Cyphellophora,Exophiala,Fonsecaea,Phialophora,and Veronaea.A total of 45 fungi morphologically identified as Fonsecaea or Cladophialophora isolated from debris and thorns of living prickly plants in Brazil were processed for taxonomic *** analysis revealed that the isolates indeed belonged to the Chaetothyriales,but only rarely an agent of chromoblastomycosis was concerned;only two strains of *** and one *** were isolated from debris *** remaining isolates belonged to hitherto unknown molecular siblings of *** novel taxa are introduced.

关键词： Black yeasts Environmental isolation Chromoblastomycosis Opportunistic fungi Virulence Infection route

载脂蛋白B介导致动脉粥样硬化脂蛋白代谢的分子机制

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中华心血管病杂志 2006年第6期34卷 571-573页

作者：李刚 Schonfeld g 重庆医科大学附属第一医院老年科心血管病组 400016 美国华盛顿大学医学院医学系动脉粥样硬化科

一、动脉粥样硬化发病最新的"潴留反应"学说　　动脉粥样硬化发病率尽管过去十年无明显上升,但依然是西方国家心脑血管疾病死亡的主要原因.迄今为止已确定许多动脉粥样硬化的危险因素,包括遗传、脂代谢异常、高血压及糖尿病,其中血脂异... 详细信息

一、动脉粥样硬化发病最新的"潴留反应"学说　　动脉粥样硬化发病率尽管过去十年无明显上升,但依然是西方国家心脑血管疾病死亡的主要原因.迄今为止已确定许多动脉粥样硬化的危险因素,包括遗传、脂代谢异常、高血压及糖尿病,其中血脂异常被认为是主要元凶。

关键词：致动脉粥样硬化脂蛋白代谢载脂蛋白B 分子机制介导脂代谢异常疾病死亡心脑血管西方国家危险因素