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The GPS-gravimetry boundary value problem

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Science China Earth Sciences 2005年第3期48卷 398-405页

作者： YU Jinhai1,2.& ZHANG Chuanding2.1. Institute of Geodesy and Geophysics of chinese academy of Sciences, Wuhan 430077, China 2. Zhengzhou Information Engineering University, Zhengzhou 450052. China Institute of Geodesy and Geophysics of chinese academy of Sciences Wuhan China Zhengzhou Information Engineering University Zhengzhou China

How to determine the earth’s external gravity field with the accuracy of O(T2. by making use of GPS data and gravity values measured on the earth’s surface is dealt with in this paper. There are two main steps: to extend these measured values on the earth’s surface onto the reference ellipsoid at first and then to seek for the integral solution of the external Neumann problem outside the ellipsoid. In addition, the corresponding judging criteria of accuracy to solve the GPS-gravity boundary value problem are established. The integral solution given in the paper not only contains all frequency-spectral information of the gravity field with the accuracy of O(T 2., but is also easily computed. In fact, the solution has great significance for both theory and prac- tice.

关键词： Neumann boundary value problem, integral solution, gravity disturbance.

Improvement of different source function expressions in SWAN model for the Bohai Sea

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Progress in Natural Science:Materials International 2005年第8期15卷 720-724页

作者： YIN Baoshu1*, YANG Dezhou1, SHA Rina 1,2.and CHENG Minghua1(1. Institute of Oceanology, chinese academy of Sciences, Qingdao 2.6071, China 2. Graduate School of the chinese academy of Sciences, Beijing 100039, China) Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China. Graduate School of the chinese academy of Sciences Beijing 100039 China

The simulating wave nearshore （SWAN） wave model has been widely used in coastal areas, lakes and estuaries. However, we found a poor agreement between modeling results and measurements in analyzing the chosen four typical cases when we used the default parameters of the source function formulas of the SWAN to make wave simulation for the Bohai Sea. Also, it was found that at the same wind process the simulated results of two wind generation expressions （Komen, Janssen） demonstrated a large difference. Further study showed that the proportionality coefficient α in linear growth term of wave growth source function plays an unperceived role in the process of wave development. Based on experiments and analysis, we thought that the coefficient α should change rather than be a constant. Therefore, the coefficient α changing with the variation of friction velocity U*was introduced into the linear growth term of wave growth source function. Four weather processes were adopted to validate the improvement in the linear growth term. The results from the improved coefficient α agree much better with the measurements than those from the default constant coefficient α. Furthermore, the large differences of results between Komen wind generation expression and Janssen wind generation expression were eliminated. We also experimented with the four weather processes to test the new white-capping mechanisms based on the cumulative steepness method. It was found that the parameters of the new white-capping mechanisms are not suitable for the Bohai Sea, but Alkyon's white-capping mechanisms can be applicable to the Bohai Sea after amendments, demonstrating that this improvement of parameter α can improve the simulated results of the Bohai Sea.

关键词： waves SWAN model wave growth source function new proportionality coefficient formula.

A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

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Science China Earth Sciences 2006年第6期49卷 622-631页

作者： TIAN Xiangjun1,2. XIE Zhenghui1, ZHANG Shenglei1 & LIANG Miaoling1 1. LASG, Institute of Atmospheric Physics, chinese academy of Sciences, Beijing 10002., China 2. Graduate School of the chinese academy of Sciences, Beijing 100039, China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate School of the chinese academy of Sciences Beijing China

Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often sin-gle-valued function of storage-discharge under a steady or “quasi-steady” state, which cannot rep-resent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new sub-surface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an ex-ample river basin, which shows that the new model can simulate the subsurface flow reasonably.

关键词： Zsubsurface runoff parameterization Boussinesq-storage equation waterstorage and recharge

Physical mechanisms of plant roots affecting weathering and leaching of loess soil

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Science China Earth Sciences 2006年第9期49卷 1002-1008页

作者： LI Yong1,2. ZHANG Qingwen1,2. WAN Guojiang3, HUANG Ronggui3, PIAO Hechun3, BAI Lingyu2.& LI Lu2.1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, chinese academy of Sciences, Yangling 712.00, China 2. Institute of Agro-Environment and Sustainable Development, chinese academy of Agricultural Sciences, Beijing 100081, China 3. Institute of Geochemistry, chinese academy of Sciences, Guiyang 550002. China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Yangling China Institute of Agro-Environment and Sustainable Development Chinese Academy of Agricultural Sciences Beijing China Institute of Geochemistry Chinese Academy of Sciences Guiyang China

Plant roots have potential impacts on soil mineral weathering and *** objective is to understand the physical mechanisms of plant roots affecting weathering andleaching of loess soil. Root densities were measured through the method of a large-size dug profile,and transport fluxes of soil elements were determined using an undisturbed monolith soilinfiltration device on the hilly and gully regions of the chinese Loess Plateau. The results showthat the improvement effects of soil environment by plant roots are mainly controlled by the densityand weight of the fibrous roots with the diameters less than 1 mm. Plant roots have the strongereffects on soil physical properties than chemical properties. The principal components analysis(PCA) indicates that soil physical properties by plant roots account for 56.7% of variations in soilenvironment whereas soil chemical properties and pH contribute about 2..2. of the soil *** roles of plant roots in controlling soil weathering and leaching increased in the followingorder: infiltration enhancement > increase of bio-active substance > stabilization of soilstructure. The effects of plant roots on soil mineral weathering and leaching can be quantifiedusing the multiple regression models with the high prediction accuracies developed in this study.

关键词： plant roots, soil weathering and leaching rates, soil environment field, principal components analysis (PCA), chinese Loess Plateau.

Evaluation of Sustainable Land Management and Diagnosis of Obstacle at County Scale in Sichuan Basin:Taking Lezhi County as Example

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2. 3 , LIU Qing 1 1. Chengdu Institute of Biology, chinese academy of Sciences, Chengdu 610041, Sichuan,China 2. Graduate University of chinese academy of Sciences, Beijing 100049, China 3. academy of Land Reconnaissance and Layout of Sichuan Province , Chengdu 610031, Sichuan, China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu Sichuan China Graduate University of chinese academy of Sciences Beijing China academy of Land Reconnaissance and Layout of Sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in Sichuan Basin, Southwest of China, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2.01. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2.01. The value of obstacles degree of five indicators exceeded 5 in 1990, but in 2.01, only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

Structural and microstructural transformations in Bi_2.r_2.a_(1-x)Y_xCu_2._(8+y) system

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chinese Science Bulletin 1997年第3期42卷 192-196页

作者： SONG Chengyu, WEN Shulin and CHE Guangcan1. Shanghai Institute of Ceramics, chinese academy of Sciences, Shanghai 2.0050, China 2. State Key Laboratory of Supercon-ductivity, Institute of Physics, chinese academy of Sciences, Beijing 100080, China Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai 200050 China

SINCE the discovery of high-Tc superconductors, experiments have revealed that the phase diagrams of La2.xSrxCuO4 and YBa2.u3O6+x resemble each other. The antiferromagnetic phase is commonly situated in the vicinity o... 详细信息

SINCE the discovery of high-Tc superconductors, experiments have revealed that the phase diagrams of La2.xSrxCuO4 and YBa2./sub>Cu3O6+x resemble each other. The antiferromagnetic phase is commonly situated in the vicinity of the superconductive phase. In Bi-2.12.sys-

关键词： Bi2.r2.a1-xYxCu2.y substitution structural transformation.

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2. 3, ZHANG Jin4 1. Institute of Geodesy and Geophysics, chinese academy of Sciences, Wuhan 430077, China 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, chinese academy of Sciences, Wuhan 430077, China 3. Graduate School of chinese academy of Sciences, Beijing 100049, China 4. Department of Surveying and Mapping, Taiyuan University of Technology, Taiyuan 03002., China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Key Laboratory of Dynamic Geodesy Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School of chinese academy of Sciences Beijing 100049 China Department of Surveying and Mapping Taiyuan University of Technology Taiyuan 030024 China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3 , YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, China 2. Center for Condensed Matter Physics, Institute of Physics, chinese academy of Sciences, Beijing 100080, China 3. BSRF, Institute of High Energy Physics, chinese academy of Sciences, Beijing 100039, China Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao China Center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China BSRF Institute of High Energy Physics Chinese Academy of Sciences Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.

chinese Society of Cardiology guidelines on the diagnosis and treatment of adult fulminant myocarditis

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Science China(Life Sciences) 2024年第5期67卷 913-939页

作者： chinese Society of Cardiology,chinese Medical Association,Writing Group Jiangang Jiang Hongyang Shu Dao Wen Wang Rutai Hui Chenze Li Xiao Ran Hong Wang Jing Zhang Shaoping Nie Guanglin Cui Dingcheng Xiang Qun Shao Shengyong Xu Discussion experts:Ning Zhou Yuming Li Wei Gao Yuguo Chen Yuan Bian Guoping Wang Liming Xia Yan Wang Chunxia Zhao Zhiren Zhang Yuhua Zhao Jianan Wang Shaoliang Chen Hong Jiang Jing Chen Xianjin Du Mao Chen Yinxian Sun Sheng Li Hu Ding Xueping Ma Hesong Zeng Li Lin Shenghua Zhou Likun Ma Ling Tao Juan Chen Yiwu Zhou Xiaomei Guo 不详 Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100037China Zhongnan Hospital of Wuhan University Wuhan 430062China Fuwai Huazhong Cardiovascular Hospital Zhengzhou 450003China Beijing Anzhen Hospital Capital Medical UniversityBeijing 100029China Guangzhou General Hospital of Guangzhou Military Command Guangzhou 510010China Harbin Medical University Cancer Hospital Harbin 150081China Union Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Taida Hospital Tianjin 300457China Peking University Third Hospital Beijing 100191China Qilu Hospital of Shandong University Jinan 250012China Kanghua Hospital DongguanGuangzhou 523080China Second Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310003China Nanjing First Hospital Nanjing Medical UniversityNanjing 210006China Renmin Hospital of Wuhan University Wuhan 430060Wuhan West China Hospital Sichuan UniversityChengdu 610044China First Hospital of China Medical University Shenyang 110002China General Hospital of Ningxia Medical University Yinchuan 750003China The Second Xiangya Hospital Central South UniversityChangsha 410012China The First Affiliated Hospital of USTC University of Science and Technology of ChinaHefei 230002China The First Affiliated Hospital of Air Force Medical University Xi’an 710032China Central Hospital of Wuhan City Wuhan 430014China Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030China

Fulminant myocarditis is an acute diffuse inflammatory disease of *** is characterized by acute onset,rapid progress and high risk of *** pathogenesis involves excessive immune activation of the innate immune system and formation of inflammatory *** to China’s practical experience,the adoption of the“life support-based comprehensive treatment regimen”(with mechanical circulation support and immunomodulation therapy as the core)can significantly improve the survival rate and long-term *** emphasis is placed on very early identification,very early diagnosis,very early prediction and very early treatment.

关键词： fulminant myocarditis guidelines life support-based comprehensive treatment regimen diagnosis treatment cytokine storm overactivation of immunity