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New Damage-locating Method for Bridges Subjected to a Moving Load

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Journal of Ocean University of China 2007年第2期6卷 199-204页

作者： LIU Fushun LI Huajun YU Guangming ZHANG Yantao wang weiying SUN Wanqing College of Engineering Ocean University of China Qingdao 266071 P. R. China College of Civil Enginering Qingdao Technologyical University Qingdao 266033 P. R. China Shengli Engineering Consulting Co. Ltd Dongving 257026 P. R. China Center for Engineering Test and Appraisal Qingdao Technological University Qingdao 266033 P. R. China

A new damage-locating method for bridges subjected to a moving load is presented, and a new ‘moving load dam- age-locating indicator’ (MLDI) is introduced. A vehicle is modeled as a moving load, the bridge is simplified as an Euler-Bernoulli beam, and the damage is simulated by a reduction of stiffness properties of the elements. The curvature and MLDI values at each node of the baseline model (undamaged) and the damage model are computed respectively. Then the damage or damages can be located from a sudden change of the MLDI value. The feasibility and effectiveness of the proposed method are validated by nu- merical simulation. The results indicate that the method is effective, being able to not only locate a single damage accurately, but also locate multiple damages in simply-supported bridges, including multiple damages in continuous bridges. The results also indicate that the MLDI can accurately locate damages under 5% measurement noise.

关键词： damage-locating bridge moving load curvature

Differences in the gene expressive quantities of carbonic anhydrase and cysteine synthase in the weathering of potassium-bearing minerals by Aspergillus niger

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Science China Earth Sciences 2013年第11期56卷 2135-2140页

作者： SUN LeiLei XIAO LeiLei XIAO Bo wang weiying PAN Chen wang ShiJie LIAN Bin Jiangsu Key Laboratory for Microbes and Functional Genomics Jiangsu Engineering and Technology Research Center for MicrobiologyCollege of Life ScienceNanjing Normal University State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of Sciences

We investigated the differences in the gene expression of carbonic anhydrase （CA） and cysteine synthase （CysM） between two weathering conditions, with either soluble potassium or insoluble potassium. We cultured a strain of A. niger by adopting a variant Czapek medium （using NazHPO4 as a substitute for KzHPO4） in two groups, Group A （containing silicate minerals bearing potassium but without KC1） and Group B （with KCI） . We extracted the mRNAs of CA and CysM from these two groups and performed real-time quantitative polymerase chain reactions （RT-qPCR）. We constructed relative standard curves by using glyceraldehyde-3-phosphate dehydrogenase （GAPDH） as the reference to confirm a consistent amplification effi- ciency of the target genes （CA and CysM） and the reference gene and quantified the gene expression of the targets in a relative manner. Our results showed that CA and CysM in Group A were upregulated for 1.7 times and 11.7 times, respectively, com- pared with those in Group B. Furthermore, we also analyzed some metabolic pathways and functions of the A. niger-induced weathering of potassium-bearing minerals, which involved the synthesizing of these two enzymes. Thus our work provides materials for further study of the roles of A. niger in the metabolic regulation during the weathering process of potassi- um-beating minerals.

关键词： Aspergillus niger potassium-bearing minerals potassium feldspar carbonic anhydrase cysteine synthase RT-qPCR

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Dark current mechanism of unpassivated mid wavelength type II InAs/GaSb superlattice infrared photodetector

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Chinese Science Bulletin 2014年第28期59卷 3696-3700页

作者： Qiong Li Wenquan Ma Yanhua Zhang Kai Cui Jianliang Huang Yang Wei Ke Liu Yulian Cao weiying wang Yali Liu Peng Jin Laboratory of Nano-Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences

We investigate the dark current mechanism for an unpassivated mid wavelength(MW) type II InAs/GaSb superlattice infrared photodetector by doing the variablearea diode tests. The bulk resistance-area product and the resistivity due to the surface current are determined to be17.72 X cm2 and 704.23 X cm at 77 K, respectively. It is found that for all the mesa sizes used, the dark current is dominated or predominated by the surface component, and with scaling back the mesa size, the surface current increases while the bulk component decreases. The activation energy is determined to be 145 meV for the temperature range around 140–280 K, while it is 6 meV when temperature is below 100 K. It is also found that the dark current is dominated by the generation-recombination current for the MW device when temperature is between140 and 280 K.

关键词： InAs 电流机制红外光电探测器波长型超晶格锑化镓钝化温度范围

Catalytic activity of Setd2 is essential for embryonic development in mice: establishment of a mouse model harboring patient-derived Setd2 mutation

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Frontiers of Medicine 2024年第5期18卷 831-849页

作者： Shubei Chen Dianjia Liu Bingyi Chen Zijuan Li Binhe Chang Chunhui Xu Ningzhe Li Changzhou Feng Xibo Hu weiying wang Yuanliang Zhang Yinyin Xie Qiuhua Huang Yingcai wang Stephen DNimer Saijuan Chen Zhu Chen Lan wang Xiaojian Sun Shanghai Institute of Hematology State Key Laboratory of Omics and DiseasesNational Research Center for Translational Medicine at ShanghaiRuijin Hospital Affiliated to Shanghai Jiao Tong University School of Medicineand School of Life Sciences&BiotechnologyShanghai Jiao Tong UniversityShanghai 200025China CAS Key Laboratory of Tissue Microenvironment and Tumor Shanghai Institute of Nutrition and HealthShanghai Institutes for Biological SciencesUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200031China Department of Clinical Laboratory The First People's Hospital of LianyungangThe Affiliated Lianyungang Hospital of Xuzhou Medical UniversityLianyungang 222000China Sylvester Comprehensive Cancer Center and Department of Medicine University of Miami Miller School of MedicineMiamiFL 33136USA Department of Biomedical Science Schmidt College of MedicineFlorida Atlantic UniversityBoca RatonFL 33431USA

SETD2 is the only enzyme responsible for transcription-coupled histone H3 lysine 36 trimethylation(H3K36me3).Mutations in SETD2 cause human diseases including cancer and developmental *** mice,Setd2 is essential for embryonic vascular *** that many epigenetic modifiers have recently been found to possess noncatalytic functions,it is unknown whether the major function(s)of Setd2 is dependent on its catalytic activity or ***,we established a site-specific knockin mouse model harboring a cancer patientderived catalytically dead Setd2(Setd2-CD).We found that the essentiality of Setd2 in mouse development is dependent on its methyltransferase activity,as the Setd2 CD/CD and Setd2^(−/−)mice showed similar embryonic lethal phenotypes and largely comparable gene expression ***,compared with Setd2^(−/−),the Setd2 CD/CD mice showed less severe defects in allantois development,and single-cell RNA-seq analysis revealed differentially regulated allantois-specific 5′Hoxa cluster genes in these two ***,this study clarifies the importance of Setd2 catalytic activity in mouse development and provides a new model for comparative study of previously unrecognized Setd2 functions.

关键词： Setd2 H3K36 methylation epigenetics embryonic development cancer

Measurement and Scaling of Mercury on Soil and Air in a Historical Artisanal Gold Mining Area in Northeastern China

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Chinese Geographical Science 2019年第2期29卷 245-257页

作者： wang Zhaojun ZHANG Gang CHEN Xiaobing ZHAO Qiaojing wang weiying SHENG Lianxi BIAN Hongfeng LI Zhenxin wang Deli State Key Lab for Environmental Protection Wetland Ecology and Vegetation Restoration Northeast Normal University School of Environment Northeast Normal University Institute of Grassland Science Northeast Normal University School of Food and Environment Dalian University of Technology

The Jiapigou gold mine area, located in the upper reaches of the Songhua River, was the first and largest artisanal gold mine once in China, and it used to be prominent in two marking years(1870 and 1974). Jiapigou area had a gold mining history of more than 190 years, which was first opened in 1820. Gold extraction with algamation was applied as the dominant method of excavation from 1940 to 2008, and a total of more than 100 t of gold were extracted from the mine using this method and it was estimated that 100–200 t Hg were released, thus causing severe mercury environmental pollution in the mining area. In the experimental campaigns of this study, in situ air and soil Hg concentrations and air-soil Hg fluxes were measured from April 2009 to December 2011. The results showed that in the study area the total gaseous mercury(TGM) concentration exhibited remarkable spatial and temporal distribution patterns, i.e. the TGM gradually decreased following the increase in distance to gold mining sites in space, and the values in spring, summer and autumn were elevated by 1–2 orders of magnitude in comparison with those in winter. Furthermore, at other sampling sites the total soil mercury(TSM) concentration in spring was higher than that in autumn, except for the contrary laws demonstrated at the Erdaogou mining site. However, in spring and winter the Hg flux between air and soil was under the control of different environmental factors, and the characteristics were clear and distinct. In spring the Hg flux between air and soil was directly under the control of solar irradiation, and the releasing process was predominant with a remarkable positive correlation to solar irradiation. Nevertheless, in winter the Hg fluxes were indirectly under the control of solar irradiation, which caused thermal inversion due to the thick snow cover. The depositing process was predominant and the correlations between Hg flux and air temperature was remarkably negative, and there was a positiv

关键词： artisanal gold mine mercury(Hg) algamation flux terrain soil

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聚合物驱最佳驱油速度的选择

石油钻采工艺 1996年第1期18卷 66-68,75页

作者：汪伟英江汉石油学院开发系

聚合物溶液在孔隙介质中流动时，有效粘度、粘弹性、分子滞留量都是速度的函数。本文研究了聚合物溶液在孔隙介质中的流变特性，找出聚合物开始产生拉伸变形所对应的临界流速VC1以及开始出现胀流型特征的临界流速VC2。在此基础之上，通... 详细信息

聚合物溶液在孔隙介质中流动时，有效粘度、粘弹性、分子滞留量都是速度的函数。本文研究了聚合物溶液在孔隙介质中的流变特性，找出聚合物开始产生拉伸变形所对应的临界流速VC1以及开始出现胀流型特征的临界流速VC2。在此基础之上，通过驱油试验进一步研究过反对聚合物驱采收率的影响，认为存在一个最佳驱油速度范围，在此速度范围内采收率最高。

关键词：聚合物多孔介质粘弹性驱油效率化学驱油

加强国家科普能力建设,服务新时代国家战略需求

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中国科学院院刊 2023年第5期38卷 740-747页

作者：王挺王唯滢王丽慧中国科普研究所北京100081

新时代国家科普能力表现为一个国家向公众持续提供有效科普产品和服务,提升全民科学素质、营造科学文化、促进科技成果转化进而支撑创新发展的综合实力。文章基于我国科普能力的理论研究与建设实践,分析了当前我国科普能力建设中的不足... 详细信息

新时代国家科普能力表现为一个国家向公众持续提供有效科普产品和服务,提升全民科学素质、营造科学文化、促进科技成果转化进而支撑创新发展的综合实力。文章基于我国科普能力的理论研究与建设实践,分析了当前我国科普能力建设中的不足和服务新时代国家发展战略的科普能力发展方向,尝试为加强国家科普能力建设、服务创新驱动发展、助力实现中国式现代化提出有益建议。

关键词：国家科普能力科普能力建设科学普及中国式现代化

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文本信息辅助图像差异描述生成

北京航空航天大学学报 2022年第8期48卷 1436-1444页

作者：陈玮婧王维莹金琴中国人民大学信息学院北京100872

图像描述生成任务要求机器自动生成自然语言文本来描述图像所呈现的语义内容,从而将视觉信息转化为文本描述,便于对图像进行管理、检索、分类等工作。图像差异描述生成是图像描述生成任务的延伸,其难点在于如何确定2张图像之间的视觉语... 详细信息

图像描述生成任务要求机器自动生成自然语言文本来描述图像所呈现的语义内容,从而将视觉信息转化为文本描述,便于对图像进行管理、检索、分类等工作。图像差异描述生成是图像描述生成任务的延伸,其难点在于如何确定2张图像之间的视觉语义差别,并将视觉差异信息转换成对应的文本描述。基于此,提出了一种引入文本信息辅助训练的模型框架TA-IDC。采取多任务学习的方法,在传统的编码器-解码器结构上增加文本编码器,在训练阶段通过文本辅助解码和混合解码2种方法引入文本信息,建模视觉和文本2个模态间的语义关联,以获得高质量的图像差别描述。实验证明,TA-IDC模型在3个图像差异描述数据集上的主要指标分别超越已有模型最佳结果12%、2%和3%。

关键词：图像差异描述模态融合图像描述计算机视觉自然语言处理

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中国科幻小说的文学价值与审美批评

中州学刊 2008年第1期 229-233页

作者：王卫英武汉大学文学院湖北武汉430072

科幻小说是科学与文学相结合的产物,在文学审美本质上,它的价值既不是科学本身,也不是传统意义上的文学幻想,而是基于科学背景上的人类幻想,或以幻想形式表达出来的人们对科学精神的向往。科学性和幻想性是科幻小说的两大基本美学特性... 详细信息

科幻小说是科学与文学相结合的产物,在文学审美本质上,它的价值既不是科学本身,也不是传统意义上的文学幻想,而是基于科学背景上的人类幻想,或以幻想形式表达出来的人们对科学精神的向往。科学性和幻想性是科幻小说的两大基本美学特性。从我国20世纪科幻小说整体发展状况看,中国科幻小说创作经历了从"科普论"、"科学人生观"到"回归自我"的价值转变,在这个转变过程中,"科普论"创作曾一度处于中心价值。

关键词：中国科幻小说文学价值审美批评