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Application of the moist vorticity vector in the analysis of a heavy rainfall event in North china

Progress in Natural Science:Materials International 2007年第12期17卷 1457-1465页

作者： Zhao Yu1,2.3, Wang Jianguo4 and Xue Deqiang2.1. Laboratory of Cloud-Precipitation Physics and Severe Storms, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china 2. Shandong Provincial {2. Observatory, Jinan 2.0031, china 3. Graduate University of Chinese Academy of Sciences, beijing 100039, china 4. Shandong Provincial {2. Bureau, Jinan 2.0031, china) Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shandong Provincial meteorological Observatory Jinan 250031 China Graduate University of Chinese Academy of Sciences Beijing 100039 China Shandong Provincial meteorological Bureau Jinan 250031 China

The moist vorticity vector (MVV), defined as (ζa×▽qv)/ρ introduced by Gao et al. is used to study a heavy rainfall event in North china. The MVV has zonal, meridional and vertical components in a three-dimensional framework. Analysis of domain-mean and mass-integrated quantities shows that the variation of the vertical component of the MVV closely follows the variation of the cloud hydrometeors, with a linear correlation coefficient of 0.95, indicating that the vertical component of the MVV is strongly associated with midlatitude convection. Further analysis shows that the vertical component of the MVV reflects the interaction between the horizontal vorticity and the horizontal specific humidity gradient, which can associate dynamic and thermodynamic processes with cloud microphysical processes. Thus, this study can help to understand how the interaction between circulations and clouds aids the development of convection, and the MVV can be used to trace the development and evolution of heavy rainfall.

关键词： moist vorticity vector heavy rainfall modeling study.

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GEOSTIONARY meteorological SATELLITE FY-2.OF china

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空间科学学报 1998年第S1期18卷 71-74页

作者： FANG Zong-yi DONG Chao-hua (Natzonal Satellite meteorological center,{2. meteorological Administrution, beijing 100081)

The first FY-2.geostationary metebrological satellite was lauched June 10, 1997flom Xichang satellite launching center by Long March-3 launching *** paper is to provide users with a brief description of the satellite ... 详细信息

关键词： Geostationary meteorological satellite Radiometer Signal charactcristics

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A preliminary study on vegetation-erosion dynamics and its applications

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Science china Earth Sciences 2005年第5期48卷 689-700页

作者： WANG Zhaoyin 1,2., WANG Guangqian 1 , LI Changzhi 1 & WANG Feixin 1 1. Department of Hydraulic Engineering, Tsinghua University, beijing 100084, china 2. Inter{2. Research and Training center on Erosion and Sedimentation, beijing 100084, china 1. Department of Hydraulic Engineering Tsinghua University 100084 Beijing China 2. International Research and Training center on Erosion and Sedimentation 100084 Beijing China

Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

关键词： vegetation-erosion dynamics, human activities, coupled differential equations, erosion control, vigor ofvegetation.

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GLOBAL CLIMATE CHANGES AND THE TOURISM OF china

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Journal of Geographical Sciences 1996年第2期6卷 97-102页

作者： Ren Guoyu(national Climate center,{2.People’s Republic of china) national Climate center Beijing 100081 China

The future global climate changes induced by the increased atmospheric CO2.concentration is receiving much attention from the scientific community as well as the public. Model simulations and palaeoclimatic data studies show an evident change in temperature and precipitation over china will occur under conditions of the global warming. Possible scenarios of the future climates are given here for china on the basis of synthesizing model simulations and palaeoclimatic data. Most parts of china will experience an increase in temperature, but the warming may be more remarkable in winter in h1e northern half of the country. Increase in precipitation will be seen in nearly every parts of the eastern china, and it will be larger in North and Northeast china. Impacts of the climate changes on the national tourism are assessed. Regions suitable for tourisin development in terms of climate comfortable index will shift northward. Some scenic spots and toruism facilities will be damaged due to sea level rise and increased rainfall. Some regions will benefit from the dimate change, but the tourism industry as a whole will be negatively affected.

关键词： IPCC GLOBAL CLIMATE CHANGES AND THE TOURISM OF china

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Study on the unified algorithm for three-dimensional complex problems covering various flow regimes using Boltzmann model equation

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Science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 124-138页

作者： LI ZhiHui1,2.& ZHANG HanXin1 1 national Laboratory for Computational Fluid Dynamics, beijing 100083,{2. 2.2. Aerodynamics Research and Development center, Hypervelocity Aerodynamics Institute, Mianyang 62.000,{2. 1. national Laboratory for Computational Fluid Dynamics Beijing 100083 China 2. china Aerodynamics Research and Development center Hypervelocity Aerodynamics Institute Mianyang 621000 China

The Boltzmann simplified velocity distribution function equation describing the gas transfer phenomena from various flow regimes will be explored and solved numerically in this study. The discrete velocity ordinate method of the gas kinetic theory is studied and applied to simulate the complex multi-scale flows. Based on the uncoupling technique on molecular movement and colliding in the DSMC method, the gas-kinetic finite difference scheme is constructed to directly solve the discrete velocity distribution functions by extending and applying the unsteady time-splitting method from computational fluid dynamics. The Gauss-type discrete velocity numerical quadrature technique for different Mach number flows is developed to evaluate the macroscopic flow parameters in the physical space. As a result, the gas-kinetic numerical algorithm is established to study the three-dimensional complex flows from rarefied transition to continuum regimes. The parallel strategy adapted to the gas-kinetic numerical algorithm is investigated by analyzing the inner parallel degree of the algorithm, and then the HPF parallel processing program is developed. To test the reliability of the present gas-kinetic numerical method, the three-dimensional complex flows around sphere and spacecraft shape with various Knudsen numbers are simulated by HPF parallel computing. The computational results are found in high resolution of the flow fields and good agreement with the theoretical and experimental data. The computing practice has confirmed that the present gas-kinetic algorithm probably provides a promising approach to resolve the hypersonic aerothermodynamic problems with the complete spectrum of flow regimes from the gas-kinetic point of view of solving the Boltzmann model equation.

关键词： Boltzmann model equation kinetic theory velocity distribution function discrete velocity ordinate technique hypersonic flow parallel computing numerical methods

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A three-dimensional variational ocean data assimilation system:Scheme and preliminary results

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Science china Earth Sciences 2006年第11期49卷 1212-1222页

作者： ZHU Jiang1,2. ZHOU Guangqing1, YAN Changxiang1, FU Weiwei1 & YOU Xiaobao1,3 1. International center for Climate and Environment Sciences, Institute of Atmospheric Physics, Chinese Academy of Sciences, {2. 10002., china 2. Jiangsu Key Laboratory of meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 2.0044, china 3. {2. Institute of Applied Meteorology, {2. 10002., china 1. International center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Jiangsu Key Laboratory of meteorological Disaster Nanjing University of Information Science and Technology Nanjing 210044 China 3. beijing Institute of Applied Meteorology Beijing 100029 China

A new 3DVAR-based Ocean Variational Analysis System (OVALS) is developed. OVALS is capable of assimilating in situ sea water temperature and salinity observations and satellite altimetry data. As a component of OVALS, a new variational scheme is proposed to assimilate the sea surface height data. This scheme considers both the vertical correlation of background errors and the nonlinear temperature-salinity relationship which is derived from the generalization of the linear balance constraints to the nonlinear in the 3DVAR. By this scheme, the model temperature and salinity fields are directly adjusted from the altimetry data. Additionally, OVALS can assimilate the temperature and salinity profiles from the ARGO floats which have been implemented in recent years and some temperature and salinity data such as from expendable bathythermograph, moored ocean buoys, etc. A 2.-year assimilation experiment is carried out by using OVALS and the Tropical Pacific circulation model. The results show that the assimilation system may effectively improve the estimations of temperature and salinity by assimilating all kinds of observations. Moreover, the root mean square errors of temperature and salinity in the upper depth less than 42. m reach 0.63℃ and 0.34 psu.

关键词： data assimilation, 3DVAR, sea surface height, ARGO floats.

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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, {2. 100080, china 3. BSRF, Institute of High Energy Physics, Chinese Academy of Sciences, {2. 100039, china 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 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.

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AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

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Science china Chemistry 2006年第3期49卷 256-266页

作者： GE Xiaopeng1, ZHOU Yanmei2. Lü Chunhua1 & TANG Hongxiao1 1. State Key Laboratory of Environmental Aquatic Chemistry, Research center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085,{2. 2. School of Civil Engineering & Architecture, beijing Jiaotong University, beijing 100044,{2. 1. State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. School of Civil Engineering & Architecture Beijing Jiaotong University Beijing 100044 China

Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and Tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the Tianjin humic sample is found to form small spheres with 2.0 to 330 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indica- tive of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic sub- stances in the sorption of environmental pollutants.

关键词： atomic force microscopy (AFM) dissolved humic substances morphology aggregation adsorption

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Association between ICU quality and in-hospital mortality of V-V ECMO-supported patients—the ECMO quality improvement action(EQIA)study:a national cohort study in china from 2.17 to 2.19

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Frontiers of Medicine 2024年第2期18卷 315-326页

作者： Wei Cheng Jieqing Chen Xudong Ma Jialu Sun Sifa Gao Ye Wang Longxiang Su Lu Wang Wei Du Huaiwu He Yujie Chen Zunzhu Li Qi Li Jianhua Sun Hongbo Luo Jinbang Liu Guangliang Shan Bing Du Yanhong Guo Dawei Liu Chang Yin Xiang Zhou on behalf of the china national Critical Care Quality Control {2.-the ECMO quality improvement action(EQIA)study Department of Critical Care Medicine State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing100730China Information center Department/Department of Information Management State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalPeking Union Medical College&Chinese Academy of Medical SciencesBeijing100730China Department of Medical Administration National Health Commission of the People’s Republic of ChinaBeijing100044China School of Population Medicine and Public Health Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing100730China Department of Epidemiology and Biostatistics Institute of Basic Medicine SciencesChinese Academy of Medical Sciences(CAMS)&School of Basic MedicinePeking Union Medical CollegeBeijing100730China national Institute of Hospital Administration National Health Commission of the People’s Republic of ChinaBeijing100044China 不详

This cohort study was performed to explore the influence of intensive care unit(ICU)quality on in-hospital mortality of veno-venous(V-V)extracorporeal membrane oxygenation(ECMO)-supported patients in *** study involved all V-V ECMO-supported patients in 318 of 1700 tertiary hospitals from 2.17 to 2.19,using data from the national Clinical Improvement System and china national Critical Care Quality Control *** quality was assessed by quality control indicators and capacity *** the 2.63 V-V ECMO-supported patients in 318 hospitals,a significant correlation was found between ECMO-related complications and *** reintubation rate within 48 hours after extubation and the total ICU mortality rate were independent risk factors for higher in-hospital mortality of V-V ECMO-supported patients(cutoff:1.5%and 7.0%;95%confidence interval:1.05–1.48 and 1.04–1.45;odds ratios:1.2. and 1.2.;P=0.012.and P=0.015,respectively).Meanwhile,the V-V ECMO center volume was a protective factor(cutoff of≥50 cases within the 3-year study period;95%confidence interval:0.57–0.83,odds ratio:0.69,P=0.0001).The subgroup analysis of 864 patients in 11 high-volume centers further strengthened these ***,ICU quality may play an important role in improving the prognosis of V-V ECMO-supported patients.

关键词： veno-venous extracorporeal membrane oxygenation in-hospital mortality high-volume centers quality control intensive care unit capacity parameters

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Entropy of three-dimensional BTZ black holes

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中国科学：物理学、力学、天文学英文版 2004年第3期47卷 277-283页

作者： GAO Changjun1,2.& SHEN Yougen1,2.3,4 1.Shanghai Astronomical Observatory,Chinese Academy of Sciences,Shanghai 2.0030,china(mailing address) 2.national Astronomical Observatories,Chinese Academy of Sciences,{2. 100012.china 3.Institute of Theoretical Physics,Chinese academy of Sciences,{2. 100080,china 4.Shanghai United center for Astrophysics,Shanghai 2.02.4,china 1. Shanghai Astronomical Observatory Chinese Academy of Sciences 200030 Shanghai China 2. national Astronomical Observatories Chinese Academy of Sciences 100012 Beijing China 3. Institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China 4. Shanghai United center for Astrophysics 200234 Shanghai China

The entropies of scalar field and neutrino field are calculated in the background of three-dimensional BTZ black hole. Considering statistical physics,we propose not to consider the superraradiant modes for bosons (Fermion fields do not display supperradiance).In fact,the nonsuperradiant modes do contribute exactly the area entropy for both bosons and fermions. The result shows that the neutrino field entropy is 3/2.times the scalar one.

关键词： BTZ black holes, entropy, supperradiant modes.

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