检索结果-南通市图书馆

Chinese Chemical Letters 2013年第7期24卷 605-608页

作者： xiao-chun yu Bo Li Bao-Hua yu Qing Xu College of Chemistry and Materials Engineering Wenzhou University

Tetrabutylammonium fluoride （TBAF） effectively facilitated a denitrative substitution reaction of electron-deficient nitroarenes with phenylthiotrimethylsilane （PhSTMS） under mild and base-free neutral conditions at room temperature, providing a practical and efficient synthesis of useful unsymmetrical diaryl thioethers. Nitroarenes bearing ortho- and para-positioned electron-withdrawing groups are the most reactive substrates, indicating that this reaction most possibly proceeded via the nucleophilic aromatic substitution （SNAr） mechanism.

关键词： Phenylthiotrimethylsilane Nitroarenes Denitrative substitution Unsymmetrical diaryl thioethers Nucleophilic aromatic substitution

Effect of isothermal temper embrittlement and subsequent hydrogen embrittlement on tensile properties of 2.25Cr-1Mo-0.25V base metal and welded metal

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2021年第11期28卷 1426-1438页

作者： Zhi-peng Shen Wei Fu Ling-rui Kong Han-han Ma xiao-hua He xiao-chun yu Chang-yu Zhou School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816JiangsuChina Jiangsu Key Lab of Design and Manufacture of Extreme Pressure Equipment Nanjing 211816JiangsuChina

2.25Cr–1Mo–0.25V base metal(BM)and welded metal(WM)with different temper embrittlement states were obtained by isothermal temper embrittlement *** ductile–brittle transition temperature and the carbide size of temper embrittled 2.25Cr–1Mo–0.25V BM and WM increased with the isothermal tempering *** increase in temper embrittlement time leads to a decrease in yield strength(YS)and ultimate tensile strength(UTS).Hydrogen embrittlement(HE)can decrease the ductility and increase YS and UTS of the *** hydrogen embrittlement sensitivity and microstructure analysis both show a combined effect of HE and temper *** deeper the temper embrittlement,the more sensitive the material to *** the hydrogen content in the material is low,the WM is less susceptible to HE due to its welding defects.

关键词： 2.25Cr–1Mo–0.25V base metal Temper embrittlement Hydrogen embrittlement Mechanical property Combined effect

Rhodium-catalyzed aerobic N-alkylation of sulfonamides with alcohols

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2011年第9期22卷 1021-1024页

作者： Sun Lin Feng Chuan Zhi Liu Qiang Li xiao chun yu Qing Xu College of Chemistry and Materials Engineering Wenzhou University Wenzhou 325035 China

By using the famous Wilkinson＇s catalyst, N-alkylation of sulfonamides can be easily realized under mild aerobic conditions by using alcohols as the alkylating reagent, giving monoalkylated sulfonamides in high yields and selectivities with water produced as the only byproduct. This advantageous aerobic method is potentially general in substrate scope that it can also be applied to other amides, amines and alcohols.

关键词： Alcohols Sulfonamides Rhodium catalyst N-Alkylation reaction Aerobic reaction

An Optimized Approach for Extracting Approximate Functional Dependencies in XML Documents

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural Sciences 2006年第1期11卷 127-132页

作者： SHI Lei YANG xiao-chun yu Ge WANG Bin ZHOU Hua-hui School of Information Science and Engineering Northeastern University Shenyang 110004 Liaoning China

In this paper, the definition of approximate XFDs based on value equality is proposed. Two metrics, sup port and strength, are presented for measuring the degree of approximate XFD. A basic algorithm is designed for extracting minimal set of approximate XFDs, and then two optimized strategies are proposed to improve the performance. Finally, the experimental results show that the optimized algorithms are correct and effective.

关键词： XML functional dependencies strength of functional dependencies

Acupuncture at heterotopic acupoints enhances jejunal motility in constipated and diarrheic rats

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2014年第48期20卷 18271-18283页

作者： Qing-Guang Qin Xin-Yan Gao Kun Liu xiao-chun yu Liang Li Hai-Ping Wang Bing Zhu Department of Physiology Institute of Acupuncture and Moxibustion China Academy of Chinese Medical Sciences Department of Acupuncture and Moxibustion Henan Orthopedics Hospital Institute of Acupuncture and Moxibustion China Academy of Chinese Medical Sciences Shanxi University of Traditional Chinese Medicine

AIM: To investigate the effect and mechanism of acupuncture at heterotopic acupoints on jejunal motility, particularly in pathological conditions.

关键词： Acupuncture Heterotopic acupoint LI11 ST37 BL25 Jejunal motility Constipation Diarrhea C fibers Muscarinic receptors

Enhancement of bending toughness for Fe-based amorphous nanocrystalline alloy with deep cryogenic-cycling treatment

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Foundry 2025年第1期22卷 99-107页

作者： Yi-ran Zhang Dong Yang Qing-chun Xiang Hong-yu Liu Jing Pang Ying-lei Ren xiao-yu Li Ke-qiang Qiu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Qingdao yunlu Advanced Material Technology Co. Ltd.Qingdao 266232ShandongChina

The effects of deep cryogenic-cycling treatment(DCT)on the mechanical properties,soft magnetic properties,and atomic scale structure of the Fe_(73.5)Si_(13.5)B_(9)Nb_(3)Cu_(1)amorphous nanocrystalline alloy were *** DCT samples were obtained by subjecting the as-annealed samples to a thermal cycling process between the temperature of the supercooled liquid zone and the temperature of liquid *** flat plate bending testing,hardness measurements,and nanoindentation experiment,it is found that the bending toughness of the DCT samples is improved and the soft magnetic properties are also slightly *** are attributed to the rejuvenation behavior of the DCT samples,which demonstrate a higher enthalpy of ***,DCT is an effective method to enhance the bending toughness of Fe-based amorphous nanocrystalline alloys without degrading the soft magnetic properties.

关键词： deep cryogenic-cycling treatment Fe-based amorphous nanocrystalline alloy bending toughness rejuvenation

Comparison of Lipopolysaccharide and Protein Immunogens from Pathogenic Yersinia enterocolitica Bio-serotype 1B/O:8 and 2/O:9 using SDS-PAGE

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2012年第3期25卷 282-290页

作者： GU Wen Peng WANG Xin QIU Hai Yan LUO Xia xiao yu chun TANG Liu Ying KAN Biao XU Jian Guo JING Huai Qi National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and PreventionState Key Laboratory Jbr Infectious Disease Prevention and Control Beijing 102206China National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China

Objective Yersinia enterocolitica is an extracellular pathogen and its related antigens interact with the host immune system. We investigated the difference in immunological characteristics between a highly pathogenic and poorly pathogenic strain of Y. enterocolitico. Methods We used SDS-PAGE and western blotting to characterize lipopolysaccharide （LPS）, Yersinio outer membrane proteins （Yops）, membrane proteins, and whole-cell proteins from poorly pathogenic Y. enterocolitico bio-serotype 2/0：9, isolated from China, and highly pathogenic bio-serotype 1B/O：8, isolated from Japan. Results These two strains of Y. enterocolitica had different LPS immune response patterns. Comparison of their Yops also showed differences that could have accounted for their differences in pathogenicity. The membrane and whole-cell proteins of both strains were similar; immunoblottting showed that the 35 kD and perhaps the 10 kD proteins were immunogens in both strains. Conclusion The major antigens of the two strains e and membrane proteins, as shown by comparing preparations. citing the host immune protein samples with response were the LPS reference and purified

关键词： Immunogens Lipopolysaccharides Outer membrane proteins Whole-cell proteins Pathogenic Yersinia enterocolitica

Distribution, characteristics, metallogenic processes and prospecting potential of terrestrial brine-type lithium deposits in the world and lithium demand situation

在线全文

学校读者我要写书评

暂无评论

China Geology 2025年第1期8卷 1-25页

作者： Dian-he Liu Cheng-lin Liu chun-lian Wang xiao-can yu MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Peking University School of Earth and Space SciencesBeijing 100871China School of Earth Resources China University of Geosciences(Wuhan)Wuhan 430074China Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China

In response to the rise of the energy storage industries such as new energy vehicles and the wide application of lithium in various fields worldwide,the global demand for lithium resources has been in explosive *** order to further comprehensively understand the global supply and demand pattern,development and utilization status,genesis of ore deposits and other characteristics of lithium resources,based on the achievements of many researchers at home and abroad,this paper systematically summarized the lithium supply and demand situation,resource endowment,deposit classification and distribution,typical geological characteristics,metallogenic factors and metallogenic regularity of terrestrial brine-type lithium deposits which are the main types of development and utilization all over the *** review shows that brine-type lithium resource and(or)reserves in the plateau salt lakes are huge and play an important *** addition,the mineralization potential of the underground brine-type lithium deposit is broad *** potential resources of underground brines are enormous,and the geothermal spring water type is also worthy of *** lithium deposits are mainly controlled by the subduction and collision of regional plate tectonics,arid climate and provenance *** of the scientific research on underground brines in the future is expected to provide another significant support for the global demand for lithium resources.

关键词： Brine in plateau salt lake Underground brine Geothermal spring brine Terrestrial brine classification Lithium migration mechanism Brine genesis Mineral exploration engineering Lithium enrich mechanism

基于MTS理论的浙江民营企业团队学习水平的调查研究

在线全文

学校读者我要写书评

暂无评论

商业经济与管理 2009年第3期 22-26页

作者：肖余春浙江工商大学工商管理学院浙江杭州310018

团队学习是企业不断发展的动力,也是近年来研究的一个热点。浙江民营企业是中国最活跃的有代表性的经济因素。基于多团队理论对浙江民营企业的团队学习进行调查研究的目的是了解它们内部团队的学习现状,分析其原因并提出建议,为当前浙... 详细信息

团队学习是企业不断发展的动力,也是近年来研究的一个热点。浙江民营企业是中国最活跃的有代表性的经济因素。基于多团队理论对浙江民营企业的团队学习进行调查研究的目的是了解它们内部团队的学习现状,分析其原因并提出建议,为当前浙江民营企业顺利转型和持续发展提供理论依据。研究发现,民营企业团队学习的内动力不足;男性团队成员内动力学习高于女性团队成员;不同年龄的团队成员在团队学习方面有显著差异;不同学历的团队成员在团队学习方面有显著差异。

关键词： MTS理论团队学习民营企业动力水平

在线全文

学校读者我要写书评

暂无评论

浙商经济转型中的组织、心理与行为机制研究

商业经济与管理 2006年第10期 9-12,21页

作者：肖余春浙江工商大学浙江杭州310018

在日趋多元化的全球化时代,浙商这个走在时代前列的经济群体也开始出现转型的需要。经济转型是社会转型的重要组成部分,要完成经济转型必先认识其动力机制,组织、心理和行为三要素是实现浙商经济转型的动力系统。浙商的成功实践证明,充... 详细信息

在日趋多元化的全球化时代,浙商这个走在时代前列的经济群体也开始出现转型的需要。经济转型是社会转型的重要组成部分,要完成经济转型必先认识其动力机制,组织、心理和行为三要素是实现浙商经济转型的动力系统。浙商的成功实践证明,充分认识和运用这种机制对于帮助浙商转型有十分重要的价值。

关键词：经济转型浙商组织心里行为机制动力系统