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International Journal of Disaster Risk Science 2024年第3期15卷 434-452页

作者： Jian Ma Katsuichiro Goda Kai Liu Silva Vitor Anirudh rao Ming Wang Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationKey Laboratory of Earthquake Disaster MitigationMinistry of Emergency ManagementHarbin150080China School of national Safety and Emergency Management Beijing Normal UniversityBeijing100875China Department of Earth Sciences Western UniversityLondonN6A 5B7Canada Global Earthquake Model Foundation 27100PaviaItaly Shenzhen Key Laboratory of Urban Disasters Digital Twin Shenzhen518023China

This study presents a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in *** model comprises a township-level residential building exposure model,a vulnerability model derived from the Chinese building taxonomy,and a regional probabilistic seismic hazard *** three components are integrated by a stochastic event-based method of the OpenQuake engine to assess the regional seismic risk in terms of average annual loss and exceedance probability curve at the city,province,and regional *** novelty and uniqueness of this study are that a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in China is developed by considering the impact of site conditions and epistemic uncertainty from the seismic hazard model.

关键词： Beijing-Tianjin-Hebei region Epistemic uncertainty Seismic risk assessment Seismic risk model

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ECG心律分析的语法逼近

国际生物医学工程杂志 1982年第2期 112-118页

作者： JAYARAM K.UDUPA ivaturi S.n.MURTHY 李长运

一、概述 ECG心律监护是很重要的,然而也是冠心护理人员每日所面临的最困难的任务之一。自动系统多数能克服人工监护的紧张和繁锁,但是由于心律失常图形的变化范围很宽,并且缺乏简便的能够明确区分正常和异常的ECG图形的可测量的特征,... 详细信息

一、概述 ECG心律监护是很重要的,然而也是冠心护理人员每日所面临的最困难的任务之一。自动系统多数能克服人工监护的紧张和繁锁,但是由于心律失常图形的变化范围很宽,并且缺乏简便的能够明确区分正常和异常的ECG图形的可测量的特征,它们的处理过程是很复杂的。心脏活动周期正常是由窦房结开始。窦房结所产生的信号传导到心房,并通过房-室结和传导组织传送到心室。心脏正常传导活动中的任一扰动都被叫做心律失常。在心律失常中有一类是由室性早搏引起的,具

关键词： ECG 句法分析言语识别分段线性图形的图形识别图象识别心律数组语法文法

Comparison of the carbon isotope composition of total organic carbon and long-chain n-alkanes from surface soils in eastern China and their significance

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Chinese Science Bulletin 2008年第24期53卷 3921-3927页

作者： rao ZhiGuo JIA GuoDong ZHU ZhaoYu WU Yi ZHAnG JiaWu State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Western China's Environment Systems Ministry of Education Lanzhou University Lanzhou 730000 China

Surface soil samples collected over a high spatial resolution in eastern China were analyzed for carbon isotope composition(δ 13C) of total organic carbon(TOC) and higher plant-derived long-chain n-alkanes,with the latter reported as weighted mean *** two sets of δ 13C values are significantly correlated and show similar trends in spatial *** spatial distribution of δ 13C shows less negative values in the mid-latitudes between 31°n and 40°n and more negative ones at higher and lower *** is consistent with previously reported carbon isotope data from surface soil phytoliths in the same region and suggests that the mid-latitude area provides relatively favorable growing conditions for C4 ***,δ 13C values of both TOC and long-chain n-alkanes from 12 surface soil samples collected from a small grassland in north China displayed similar carbon isotope values and the difference between paired δ 13C of a soil samples remains relatively *** data demonstrate that in eastern China,soil δ 13C composition of both TOC and long-chain n-alkanes is effective indicators of C3/C4 ratios of the prevailing *** work suggests that -22‰ and -32‰ are good estimated end members for the weighted mean δ 13C values of long-chain n-alkanes(C27,C29 and C31 n-alkanes) from soils under dominant C4 or C3 vegetation,allowing us to reconstruct paleovegetation trends.

关键词：植物总有机碳碳同位素表面土壤

Photocatalytic properties of P25-doped TiO_2 composite film synthesized via sol–gel method on cement substrate

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Journal of Environmental Sciences 2018年第4期30卷 71-80页

作者： Xiang Guo Lei rao Peifang Wang Chao Wang Yanhui Ao Tao Jiang Wanzhong Wang Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of Education College of EnvironmentHohai University College of Mechanics and Materials Hohai University

TiO2 films have received increasing attention for the removal of organic pollutants via photocatalysis. To develop a simple and effective method for improving the photodegradation efficiency of pollutants in surface water, we herein examined the preparation of a P25-TiO2 composite film on a cement substrate via a sol–gel method. In this case, Rhodamine B（Rh B）was employed as the target organic pollutant. The self-generated TiO2 film and the P25-TiO2 composite film were characterized by X-ray diffraction（XRD）, n2 adsorption/desorption measurements, scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, and diffuse reflectance spectroscopy（DRS）. The photodegradation efficiencies of the two films were studied by Rh B removal in water under UV（ultraviolet） irradiation. Over 4 day exposure, the P25-TiO2 composite film exhibited higher photocatalytic performance than the self-generated TiO2 film. The photodegradation rate indicated that the efficiency of the P25-TiO2 composite film was enhanced by the addition of the rutile phase Degussa P25 powder. As such, cooperation between the anatase TiO2 and rutile P25 nanoparticles was beneficial for separation of the photo-induced electrons and holes. In addition, the influence of P25 doping on the P25-TiO2 composite films was evaluated. We found that up to a certain saturation point, increased doping enhanced the photodegradation ability of the composite film. Thus, we herein demonstrated that the doping of P25 powders is a simple but effective strategy to prepare a P25-TiO2 composite film on a cement substrate, and the resulting film exhibits excellent removal efficiency in the degradation of organic pollutants.

关键词： P25-TiO2composite film Doping Photocatalysis Sol–gel method Cement substrate Rhodamine B

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应变片法船舶推进轴系计算机辅助对中

船舶 1992年第1期3卷 46-52页

作者： M.n.Keshava rao 吴健芜湖长江轮船公司

本文介绍了用有限元法和应变片技术计算所有轴承反力的过程,如新旧船计算最佳的偏移以得到理想轴承反力的计算法和数字例子,轴系对中时用应变片法的优点,仅用应变片计算所有轴承(即使有3个不可接近的轴承)即时反力的过程以及轴系对中计... 详细信息

本文介绍了用有限元法和应变片技术计算所有轴承反力的过程,如新旧船计算最佳的偏移以得到理想轴承反力的计算法和数字例子,轴系对中时用应变片法的优点,仅用应变片计算所有轴承(即使有3个不可接近的轴承)即时反力的过程以及轴系对中计算机软件的框图;展现了运行条件下用应变片和船载计算机进行轴系诊断的技术。

关键词：船舶推进系统轴系 CAM

Slime coating of kaolinite on chalcopyrite in saline water flotation

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 481-488页

作者： Zhi-li Li Feng rao Shao-xian Song Yan-mei Li Wen-biao Liu COnACYT Instituto de Investigación en Metalurgiay Materiales Universidad Michoacana de San Nicolás de Hidalgo School of Resources and Environmental Engineering Wuhan University of Technology Departamento de Ingeniería en Minas Metalurgia y GeologíaUniversidad de Guanajuato Faculty of Land and Resource Engineering Kunming University of Science and Technology

In saline water flotation, the salinity can cause a distinguishable slime coating of clay minerals on chalcopyrite particles through its effect on their electrical double layers in aqueous solutions. In this work, kaolinite was used as a representative clay mineral for studying slime coating during chalcopyrite flotation. The flotation of chalcopyrite in the presence and absence of kaolinite in tap water, seawater, and gypsum-saturated water and the stability of chalcopyrite and kaolinite particles in slurries are presented. Zeta-potential distributions and scanning electron microscopy images were used to characterize and explain the different slime coating degrees and the different flotation performances. Kaolinite particles induced slime coating on chalcopyrite surfaces and reduced chalcopyrite floatability to the greatest extent when the p H value was in the alkaline range. At 0.24 wt% of kaolinite, the chalcopyrite floatability was depressed by more than 10% at alkaline p H levels in tap water. Salinity in seawater and gypsum-saturated water compressed the electrical double layers and resulted in extensive slime coating.

关键词： chalcopyrite clay minerals saline water flotation slime coating stability

The coupling between hydrodynamic and purification efficiencies of ecological porous spur-dike in field drainage ditch

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Journal of Hydrodynamics 2018年第3期30卷 373-383页

作者： Lei rao Pei-fang Wang Qing-song Dai Chao Wang College of Mechanics and Materials Hohai University Nanjing 211100 China Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of Education Hohai University Nanjing 210098 China College of Environment Hohai University Nanjing 210098 China

In this study, a series of ecological porous spur-dikes are arranged in an experiment channel to simulate a real field drainage ditch. The inside and outside flow fields of spur-dikes are determined by numerical simulations and experimental methods. An Ammonia-nitrogen（nH3-n） degradation evaluation model is built to calculate the pollution removal rate by coupling with the inner flow field of the porous spur-dikes. The variations of the total pollutant removal rate in the channel are discussed in terms of different porosities and gap distances between spur-dikes and inlet flow velocities. It is indicated that a reasonable parameter matching of the porosity and the gap distance with the flow velocity of the ditch can bring about a satisfactory purification efficiency with a small delivery quantity of ecological porous materials.

关键词： Porous water permeable material ecological spur-dike field drainage ditch pollutant removal rate coupling

Dehydroxylation action on surface of TiO_2 films restrained by nitrogen carrier gas during atomic layer deposition process

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Rare Metals 2014年第5期33卷 583-586页

作者： Zhi-Peng rao Bang-Wu Liu Chao-Bo Li Yang Xia Jun Wan Key Laboratory of Microelectronic Devices and Integration Technology Institute of Microelectronics Chinese Academy of Sciences Jiaxing Research and Commercialization Center for Microelectronics Equipment Zhejiang Institute of Advanced Technology Chinese Academy of Sciences Jiaxing Kemin Electronic Equipment & Technologies Co. LtdZhejiang Institute of Advanced Technology Chinese Academy of Sciences

A strong influence of nitrogen gas on the content of surface hydroxyl groups of TiO2 films by atomic layer deposition（ALD） was investigated by X-ray photoelectron spectroscopy（XPS）, contact angle measuring system, and UV–Vis spectrophotometer. XPS spectra of O 1s indicate that the content of surface hydroxyl groups is varied when using n2 as carrier gas. The results of water contact angles and optical reflection spectra show that the content variation of surface hydroxyl groups influences the wetting properties and optical reflectivity of TiO2 films. A surface reaction model is suggested to explain the ALD reaction process using n2 as carrier gas.

关键词： Atomic layer deposition TiO2 n2 Surface hydroxyl groups XPS Reaction model

Is the maximum carbon number of long-chain n-alkanes an indicator of grassland or forest? Evidence from surface soils and modern plants

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Chinese Science Bulletin 2011年第16期56卷 1714-1720页

作者： rao ZhiGuo WU Yi ZHU ZhaoYu JIA GuoDong HEnDERSOn Andrew Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Western China's Environmental Systems (Ministry of Education) Lanzhou University Lanzhou 730000 China Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Geographical & Earth Sciences University of Glasgow Glasgow G12 8QQ UK

The molecular distribution of long-chain n-alkanes in 62 soil samples collected from diverse locations across eastern China was *** long-chain n-alkanes were mostly dominated by n-C29 or n-C31,regardless of the overlying vegetation type at each *** results were compared with those summarized from the literature,covering more than 100 soil samples within China and more than 300 genera of modern plants distributed *** were similar n-alkane distribution patterns for most genera, with no clear differences among grasses,shrubs,and *** evidence from analyses of surface soils and modern plants indicates that the relationship between the molecular distribution of long-chain n-alkanes of surface soils and source vegetation is highly complex,and is influenced by many ***,it is suggested that source vegetation types should not be simply inferred from distribution patterns of long-chain n-alkanes in sediments.

关键词：长链正构烷烃土壤样品植物分析碳原子数证据表面中国东部地区森林

Structures of the n- and C-terminal domains of MHV-A59 nucleocapsid protein corroborate a conserved RnA-protein binding mechanism in coronavirus

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Protein & Cell 2010年第7期1卷 688-697页

作者： Yanlin Ma Xiaohang Tong Xiaoling Xu Xuemei Li Zhiyong Lou Zihe rao Life national Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Graduate University of the Chinese Academy of Sciences Beijing 100049China Laboratory of Structural Biology Tsinghua UniversityBeijing 100084China

Coronaviruses are the causative agent of respiratory and enteric diseases in animals and *** example is SARS,which caused a worldwide health threat in *** coronaviruses,the structural protein n(nucleocapsid protein)associates with the viral RnA to form the filamentous nucleocapsid and plays a crucial role in genome replication and *** structure of nterminal domain of MHV n protein also implicated its specific affinity with transcriptional regulatory sequence(TRS)*** we report the crystal structures of the two proteolytically resistant n-(nTD)and C-terminal(CTD)domains of the n protein from murine hepatitis virus(MHV).The structure of nTD in two different crystal forms was solved to 1.5Å.The higher resolution provides more detailed structural information than previous reports,showing that the nTD structure from MHV shares a similar overall and topology structure with that of SARS-CoV and IBV,but varies in its potential surface,which indicates a possible difference in RnA-binding *** structure of CTD was solved to 2.0-Åresolution and revealed a tightly intertwined *** is consistent with analytical ultracentrifugation experiments,suggesting a dimeric assembly of the n *** similarity between the structures of these two domains from SARS-CoV,IBV and MHV corroborates a conserved mechanism of nucleocapsid formation for coronaviruses.

关键词： crystal structure nucleocapsid protein murine hepatitis virus