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超流费米气体相滑移时的密度分布

物理学报 2006年第2期55卷 490-493页

作者：武宏宇尹澜北京大学物理学院北京100871

当前在冷原子和玻色爱因斯坦凝聚(BEC)领域的一个重要问题是在Feshbach共振附近的冷费米气体如何从BEC态演变到BCS(Bardeen Schrieffer Cooper)态.本文进一步研究在Feshbach共振附近超流态的相滑移现象.通过具体的数值计算,给出了费米... 详细信息

当前在冷原子和玻色爱因斯坦凝聚(BEC)领域的一个重要问题是在Feshbach共振附近的冷费米气体如何从BEC态演变到BCS(Bardeen Schrieffer Cooper)态.本文进一步研究在Feshbach共振附近超流态的相滑移现象.通过具体的数值计算,给出了费米气体在相滑移时的粒子数密度的分布,并对不同温度下的相滑移的大小进行了分析.结果表明,相滑移现象可以作为实验上判断系统是否处于超流态的一个可行的判据.

关键词：超流费米气体相滑移 Feshbach共振

Antagonistic Potential against Pathogenic Microorganisms and Hydrogen Peroxide Production of Indigenous Lactobacilli Isolated from Vagina of Chinese Pregnant Women

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Biomedical and Environmental Sciences 2008年第5期21卷 365-371页

作者： HENG-YI XU WAN-HONG TIAN CUI-XIANG WAN LI-JUN JIA lan-yin WANG JING YUAN CHUN-MEI LIU MING ZENG HUA WEI State Key Laboratory of Food Science and Technology Jiangxi-OAl Joint Research Institute Nanchang University Nanchang 330047 Jiangxi China National Institute for the Control of Pharmaceutical and Biological Products Beijing 100050 China Beijing Tiantan Hospital Beijing 100050 China Instiute of Disease Control and Prevention Academy of Military Medical Sciences Beijing 100071 China

Objective To investigate the indigenous lactobacilli from the vagina of pregnant women and to screen the isolates with antagonistic potential against pathogenic microorganisms. Methods The strains were isolated from pregnant women＇s vagina and identified using the API50CH system. The ability of the isolates to produce hydrogen peroxide was analyzed semi-quantitatively using the TMB-HRP-MRS agar. The antagonistic effects of the isolates on pathogenic microorganisms were determined with a double layer agar plate. Results One hundred and three lactobacilli strains were isolated from 60 samples of vaginal secretion from healthy pregnant women. Among them, 78 strains could produce hydrogen peroxide, in which 68%, 80%, 80%, and 88% had antagonistic effects against Candida albicans CMCC98001, Staphylococcus aureus CMCC26003, Escherichia coli CMCC44113, and Pseudomonas aeruginosa CMCC10110, respectively. Conclusion The recovery of hydrogen peroxide-producing lactobacilli decreases with the increasing pregnant age and time. The most commonly isolated species from vagina of Chinese pregnant women are Lactobacillus acidophilus and Lactobacillus crispatus. Most of L. acidophilus and L. crispatus produce a high H2O2 level.

关键词： Lactobacilli H2O2 Pregnant women Antagonistic Pathogen

An Optoelectronic thermometer based on microscale infrared-to-visible conversion devices

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Light(Science & Applications) 2022年第6期11卷 1158-1165页

作者： He Ding Guoqing Lv Xue Cai Junyu Chen Ziyi Cheng Yanxiu Peng Guo Tang Zhao Shi Yang Xie Xin Fu lan yin Jian Yang Yongtian Wang Xing Sheng Beijing Engineering Research Center of Mixed Reality and Advanced Display School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China Department of Electronic Engineering Beijing National Research Center for Information Science and TechnologyInstitute for Precision MedicineCenter for Flexible Electronics Technologyand IDG/McGovern Institute for Brain ResearchTsinghua UniversityBeijing 100084China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Thermometric detectors are crucial in evaluating the condition of target objects spanning from environments to the human ***-based thermal sensing tools have received extensive attention,in which the photon upconversion process with low autofluorescence and high tissue penetration depth is considered as a competent method for temperature monitoring,particularly in biomedical ***,we present an optoelectronic thermometer via infrared-to-visible upconversion,accomplished by integrated light receiving and emission *** fabricated thin-film,microscale devices present temperature-dependent light emission with an intensity change of 1.5%℃^(-1) and a spectral shift of 0.18 nm℃^(-1).The sensing mechanism is systematically characterized and ascribed to temperature dependent optoelectronic properties of the semiconductor band structure and the circuit operation *** device arrays showcase the capability for spatially resolved temperature ***,in vitro and in vivo experiments implemented with integrated fiber-optic sensors demonstrate real-time thermal detection of dynamic human activity and in the deep brain of animals,respectively.

关键词： visible optoelectronic thermal

Corrosion Behavior of Anodic Oxidized TiO_2 Film in Seawater

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Journal of Ocean University of China 2010年第4期9卷 376-380页

作者： WANG Min WANG Wei HE Benlin SUN Mingliang yin Yansheng LIU lan ZOU Wuyuan XU Xuefei Institute of Materials Science and Engineering Ocean University of China Qingdao 266100 P. R. China

TiO2 films were formed on metallic titanium substrates by the anodic oxidation method in H2SO4 solution under the 80V D.C..Phase component and microstructure were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).Water contact angles on titanium oxide film surface were measured under both dark and sunlight illumination *** tests were carried out in seawater under different illumination conditions by electrochemistry impedance spectrum (EIS) and polarization *** result showed that the TiO2 film prepared by the anodic oxidation method was anatase with a uniform structure and without obvious pores or cracks on its *** average water contact angle of the film was 116.4? in dark, in contrast to an angle of 42.7? under the UV illumination for 2 hours, which demonstrates good hydrophobic *** anti-corrosion behavior of the TiO2 film was declining with the extended immersion *** dark conditions, however, the hydrophobic TiO2 film retarded the water infiltrating into the *** impedance changed slowly and the corrosion current density was 2 orders of magnitude lower than that with the film illuminated by *** of those mentioned above indicate that the TiO2 film possesses much better performance under dark condition, and it can be applied as an engineering material under dark seawater environment.

关键词： TiO2 film anodic oxidation method hydrophobic corrosion resistance electrochemistry impedance spectrum(EIS)

The Cooperative Activities of CSLD2, CSLD3, and CSLD5 Are Required for Normal Arabidopsis Development

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Molecular Plant 2011年第6期4卷 1024-1037页

作者： lan yin Yves Verhertbruggen Ai Oikawa Chithra Manisseri Bernhard Knierim Lina Prak Jacob Kriiger Jensen Paul Knox Manfred Auer William G.T. Willatsa and Henrik Vibe Scheller Department of Plant Biology and Biotechnology Faculty of Life Sciences University of Copenhagen DK-1871 Frederiksberg C Denmark Joint BioEnergy Institute Feedstocks Division 5885 Hollis St Emeryville CA 94608 USA Present address： Department of Arctic and Marine Biology University of Tromso 9037 Tromse Norway Physical Biosciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Present address： Molecular Phytopathology and Genetics University of Hamburg D-22609 Hamburg Germany f Joint BioEnergy Institute Technology Division 5885 Hollis St Emeryville CA 94608 USA Life Sciences Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA Present address： Department of Plant Biology Michigan State University East Lansing MI 48824 USA Centre for Plant Sciences Faculty of Biological Sciences University of Leeds Leeds LS2 9JT UK Department of Plant and Microbial Biology University of California Berkeley CA 94720 USA Joint BioEnergy Institute Technology Division 5885 Hoilis St Emeryville CA 94608 USA

Glycosyltransferases of the Cellulose Synthase Like D （CS/D） subfamily have been reported to be involved in tip growth and stem development in Arabidopsis. The csld2 and csld3 mutants are root hair defective and the csld5 mutant has reduced stem growth. In this study, we produced double and triple knockout mutants of CSLD2, CSLD3, and CSLD5. Unlike the single mutants and the csld2/csld3 double mutant, the csld2/csld5, csld3/csld5, and csld2/csld3/csld5 mutants were dwarfed and showed severely reduced viability. This demonstrates that the cooperative activities of CSLD2, CSLD3, and CSLD5 are required for normal Arabidopsis development, and that they are involved in important processes besides the specialized role in tip growth. The mutant phenotypes indicate that CSLD2 and CSLD3 have overlapping functions with CSLD5 in early plant development, whereas the CSLD2 and CSLD3 proteins are non-redundant. To determine the biochemical function of CSLD proteins, we used transient expression in tobacco leaves. Microsomes containing heterologously expressed CSLD5 transferred mannose from GDP-mannose onto endogenous acceptors. The same activity was detected when CSLD2 and CSLD3 were coexpressed but not when they were expressed separately. With monosaccharides as exogenous acceptors, microsomal preparations from CSLD5-expressing plants mediated the transfer of mannose from GDP-mannose onto mannose. These results were supported by immunodetection studies that showed reduced levels of a mannan epitope in the cell walls of stem interfascicular fibers and xylem vessels of the csld2/csld3/csld5 mutant.

关键词： Cellulose synthase like hemicelluloses mannan glycosyltransferases polysaccharide plant development.

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光测法在混凝土表面裂缝测量中的应用

东南大学学报（自然科学版） 2005年第A1期35卷 19-22页

作者：王伟何小元尹兰东南大学土木工程学院南京210096

针对采集到的裂缝图像特征,提出一种裂缝定量分析法,即根据裂缝图像灰度。利用otsu提出的类判别法计算出图像分割的最佳阈值,进而提取图像的裂缝信息,然后通过编制的图像处理程序分析出研究区域的裂缝宽度及其方差.实验结果表明:该定量... 详细信息

针对采集到的裂缝图像特征,提出一种裂缝定量分析法,即根据裂缝图像灰度。利用otsu提出的类判别法计算出图像分割的最佳阈值,进而提取图像的裂缝信息,然后通过编制的图像处理程序分析出研究区域的裂缝宽度及其方差.实验结果表明:该定量分析法处理图像效果好,数据稳定,相关的计算结果可为实际工程的安全可靠性评估提供准确的基础数据.经实践验证,该方法简单易行.

关键词：表面裂缝光测法定量分析混凝土

A Survey on College English Learning Burnou

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Sino-US English Teaching 2013年第8期10卷 608-614页

作者： CHEN Ling JIN lan yin Zhu-hui LI Nan Beijing Information Science & Technology University Beijing China

Based on burnout theories and published researches in this field, a survey is done on non-majors＇ college English learning burnout through the methods of questionnaire and interview. A considerable degree of burnout is found among freshmen, sophomores, and juniors, regardless of gender, though there are gender differences in different aspects of learning burnout. Insights are drawn from the research data involving such aspects as learner autonomy, teaching style, curriculum design, rapport, modernized facilities, employment awareness, and so on, with an aim to suggest some strategies to overcome learning burnout and improve students＇ language competence. Future research might extend the present study to English majors and attempt a comparison in between.

关键词： English learning burnout non-majors

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煤炭企业科技创新项目全过程管理研究

煤炭技术 2021年第7期40卷 200-203页

作者：尹岚岚煤炭科学技术研究院有限公司北京100013 煤矿应急避险技术装备工程研究中心北京100013 北京市煤矿安全工程技术研究中心北京100013

开展科技创新项目是煤炭企业转型发展的重要支撑。为保障科技创新项目的顺利实施,提升项目成功率,提出了一种基于过程的煤炭企业科技创新项目管理模式。从决策管理、资源管理、项目实施、总结与改进4个方面介绍了煤炭企业科技创新项目... 详细信息

开展科技创新项目是煤炭企业转型发展的重要支撑。为保障科技创新项目的顺利实施,提升项目成功率,提出了一种基于过程的煤炭企业科技创新项目管理模式。从决策管理、资源管理、项目实施、总结与改进4个方面介绍了煤炭企业科技创新项目管理模式,为煤炭企业进行科技创新项目管理提供理论参考和决策建议。

关键词：煤炭企业科技创新项目过程管理

LiteST:一种无线传感器网络轻量级安全时间同步协议

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通信学报 2009年第4期30卷 74-85页

作者：尹香兰齐望东解放军理工大学计算机系江苏南京210007

提出了一个简单的时间同步广播报文完整性认证方法。在此基础上,结合单向链(而非复杂得多的μTESLA)提供的发送节点身份认证功能和冗余机制提供的防止内部节点攻击功能,设计了一个轻量级的安全时间同步协议LiteST(lightweight secure ti... 详细信息

提出了一个简单的时间同步广播报文完整性认证方法。在此基础上,结合单向链(而非复杂得多的μTESLA)提供的发送节点身份认证功能和冗余机制提供的防止内部节点攻击功能,设计了一个轻量级的安全时间同步协议LiteST(lightweight secure time)。理论分析和仿真实验结果表明,LiteST能够防御外部攻击并能容忍内部攻击节点发送错误信息,达到了目前最好的安全时间同步协议TinySeRSync类似的安全性。32个Mica2节点组成的原型系统实验结果表明LiteST协议取得了与没有安全机制的FTSP协议几乎相同的时间同步精度。LiteST协议与安全相关的计算开销大约只有TinySeRSync的五分之一;通信开销为其1/(2m+2),其中m为网络节点的平均邻居数;其存储开销在实际的场景下也显著降低。

关键词：无线传感器网络时间同步协议安全轻量级