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Sorption behavior of U(VI), ^(2.4)U(VI) and ^(2.8)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in china

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Science china Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3, WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of Earth Sciences, State Key Laboratory of Mineral Deposit Research, Nanjing University, Nanjing 2.0093, china 2. center of Materials {2., Nanjing University, Nanjing 2.0093, china 3. Department of Environmental Science and Engineering, Nanjing University, Nanjing 2.0093, china 4. beijing Geology Institute, Nuclear Industry, beijing 10002., china Nanjing University Nuclear Industry

The first results of sorption experiments of U(VI), 2.4U(VI) and 2.8U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 2.4U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

Improving the accuracy of image-based forest fire recognition and spatial positioning

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Science china(Technological Sciences) 2010年第S1期53卷 184-190页

作者： JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2.& CHENG Xi 1,3 1 Institute of Geographical Sciences and Natural Resources Research,Chinese Academy of Sciences,beijing 100101,china 2.2. center for Resources Satellite Data and Applications,beijing 100094,china 3Graduate University of Chinese Academy of Sciences,beijing 100049,china Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China china center for Resources Satellite Data and Applications Beijing China Graduate University of Chinese Academy of Sciences Beijing China

Forest fires are frequent natural *** is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest *** paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial ***,we discuss a method of forest fire recognition in visible-light *** are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2.excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3)improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image ***,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature ***,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central *** studies are examined and the results are found to be satisfactory.

关键词： forest fire monitoring spatial positioning accuracy improvement

Predictive Values of Body Mass Index and Waist Circumference for Risk Factors of Certain Related Diseases in Chinese Adults - Study on Optimal Cut-off Points of Body Mass Index and Waist Circumference in Chinese Adults

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Biomedical and Environmental Sciences 2002年第1期15卷 83-96页

作者： ZHOU BEI-FAN2.ooperative Meta-analysis Group of the Working Group on Obesity in china Cooperative Meta-analysis Group of the Working Group on Obesity in china

Objective For prevention of obesity in Chinese population, it is necessary to definethe optimal range of healthy weight and the appropriate cut-off points of BMI and waistcircumference for Chinese adults. The Working Group on Obesity in china under the supportof International Life Sciences Institute Focal Point in china organized a meta-{2. on therelation between BMI, waist circumference and risk factors of related chronic diseases (e. g.,high diabetes, diabetes mellitus, and lipoprotein disorders). Methods 13 population studiesin all met the criteria for enrollment, with data of 2.9 972.adults (2.-70 year) surveyed inthe 1990s. Data on waist circumference was available for 111411 persons and data on serumlipids and glucose were available for more than 80 000. The study populations located in2.provinces, municipalities and autonomous regions in china's Mainland as well as inTaiwan. Each enrolled study provided data according to a common protocol and uniformformat. The center for data management in Department of Epidemiology, Fu Wai Hospitalwas responsible for statistical {2.. Results and conclusion The prevalence ofhypertension, diabetes, dyslipidemia and clustering of risk factors all increased withincreasing levels of BMI or waist circumference. BMI at 2. with best sensitivity andspecificity for identification of the risk factors, was recommended as the cut-off point foroverweight, BMI at 2. which may identify the risk factors with specificity around 90 % wasrecommended as the cut-off point for obesity. Waist circumference beyond 85 cm for menand beyond 80 cm for women were recommended as the cut-off points for central *** of population attributable risk percent illustrated that reducing BMI to normalrange (2.) could prevent 45%-50% clustering of risk factors. Treatment of obese persons(BMI≥2.)with drugs could prevent 15%-17% clustering of risk factors. The waistcircumference controlled under 85 cm for men and under 80 cm for women

关键词： Chinese adults Overweight Obesity BMI Waist circumference

analysis of the severe group dust storms in eastern part of Northwest china

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Journal of Geographical Sciences 2002年第3期12卷 357-362页

作者： ZHOU Zijiang, WANG Xiwen(1. National Meteorological center, beijing 100081,{2. 2. Lanzhou Central MeteorologicalObservatory, Lanzhou 73002.,{2.) National Meteorological center 北京 100081 Lanzhou Central Meteorological Observatory Lanzhou 730020

Based on the available original dust storm records from 60 meteorological stations, we discussed the identification standard of severe dust storms at a single station and constructed a quite complete time series of severe group dust storms in the eastern part of Northwest china in 1954–2.01. The result shows that there were 99 severe group dust storms in this region in recent 48 years. The spatial distribution indicates that the Alax Plateau, most parts of the Ordos Plateau and most parts of the Hexi Corridor are the main areas influenced by severe group dust storms. In addition, the season and the month with the most frequent severe group dust storms are spring and April, accounting for 78.8% and 41.4% of the total events respectively. During the past 48 years the lowest rate of severe group dust storms occurred in the 1990s. Compared with the other 4 decades, on the average, the duration and the affected area of severe group dust storms are relatively short and small during the 1990s. In 2.00 and 2.01, there were separately 4 severe group dust storms as the higher value after 1983 in the eastern part of Northwest china.

关键词： eastern part of Northwest china severe group dust storms temporal and spatial distribution characteristics

Study on Transformation of CaO-Al_2._3-SiO_2.MgO System Inclusions in ZG06Cr13Ni4Mo Stainless Steel

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Journal of Iron and Steel Research International 2011年第S2期18卷 341-346页

作者： LIU Jian-hui1,3, DONG Han1,3, ZHU Rong2. LI Shi-qi2.(1. Institute for Structural Materials,Central Iron and Steel Research Institute, beijing 100081,china 2. School of Metallurgical and Ecological Engineering,University of Science and Technology beijing, beijing 100083,china 3. National Engineering Research center of Advanced Steel Technology, beijing 100081,china) Cent Iron & Steel Res Inst Inst Struct Mat Beijing 100081 Peoples R China Natl Engn Res Ctr Adv Steel Technol Beijing 100081 Peoples R China Univ Sci & Technol beijing Sch Met & Ecol Engn Beijing 100083 Peoples R China

This paper aims at generally studying on the inclusions of ZGG06Cr13Ni4Mo ultra-low carbon stainless steel used for large scale hydraulic turbine sets. On the basis of analysis the industrial test samples, thermodynamic software FactSage is used to study inclusions transformation process in CaO-SiO2.Al2.3-MgO system while stainless steel is been smelting. The results illustrate the inclusions melting points and plasticity variation law. The reasonable inclusions plasticity controlling area is found out in low melting point. The melting point is up to 12.0℃ While MgO weight concentration is 10% in CaO-SiO2.Al2.3-MgO system, SiO2. Al2.3 and CaO in inclusions are in weight concentration range of 50-70%, 10-2.% and 10-40%, respectively. For purpose of gaining low melting point inclusions, silicon alumina radio in deoxidant should be controlled between 2.5 for ultra-low carbon stainless steel refining in industry.

关键词： ZG06Cr13Ni4Mo stainless steel low melting point inclusion thermodynamic calculation

analysis on Some of Software Reliability Models

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Journal of Systems Engineering and Electronics 2001年第1期12卷 88-96页

作者： Song Xiaoqiu Software Evaluation and Test center of china Aerospace Corporation, {2. 100854, P. R. china Software Evaluation and Test center of china Aerospace Corporation Beijing 100854 P. R. China

Software reliability and maintainability evaluation tool (SRMET 3.0) is introducted in detail in this paper, which was developed by Software Evaluation and Test center of china Aerospace Mechanical Corporation. SRMET 3.0 is supported by seven software reliability models and four software maintainability models. Numerical characteristics for all those models are deeply studied in this paper, and corresponding numerical algorithms for each model are also given in the paper.

关键词： Software Reliability Evaluation Model

Magnetic Fabric of Cuizhao Pluton and ItsEmplacement Significance

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Journal of Earth Science 1999年第3期18卷 274-279页

作者： Zhou Weixin(Institute of Geology, china seismological bureau, beijing 10002.)Wan Tianfeng(Department of Geology and Mineral Resources,{2. University of Geosciences, beijing 100083) Institute of Geology China Seismological Bureau Beijing 100029 Department of Geology and Mineral Resources China University of Geosciences Beijing 100083

The new micro-structural and magnetic fabric data on Cuizhao plutou and their emplacement implications are demonstrated in this peper. The magnetic foliations develop better and the degree of magnetic susceptibility anlsotropy is larger in the margin of the pluton than that in the center,which reveals mainly horizontal compression or magma during emplacement- The mapnetic lineations are not very well developed. The magnetic fabrics in the Cuizhao pluton reveal horizontal compression like the bollooning model during emplacement near the Earth surrace. This feature was fixed in later tectonic events.

关键词： granitoid pluton magnetic fabric foliation lineation emplacement mechanism

Physical analysis and numerical simulation for the dynamic behaviour of vehicles in pitching oscillations or rocking motions

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Science china(Technological Sciences) 2007年第4期50卷 385-401页

作者： ZHANG HanXin1,2.3, ZHANG Zhao1,3, YUAN XianXu1,2. LIU Wei1, XIE YuFei1,2.& YE YouDa1,2.1 china Aerodynamics Research and Development center, Mianyang 62.000, china 2.National Laboratory for Computational Fluid Dynamics, beijing University of Aeronautics and Astronautics, beijing 100083, china 3 School of Aerospace, Tsinghua University, beijing 100084, china china Aerodynamics Research and Development center Mianyan China National Laboratory for Computational Fluid Dynamics Beijing University of Aeronautics and Astronautics Beijing China School of Aerospace Tsinghua University Beijing China

Analytical methods of nonlinear dynamics and numerical simulations for the cou-pling equations of Navier-Stokes and flight mechanics are used to study the dynamic behaviour of pitching motions of reentry capsules with the variation of Mach number, and rocking motions of swept wings with the variation of angle of attack. Conditions under which the dynamic instability, Hopf bifurcation and saddle-node bifurcation occur are obtained. The node-saddle-node topological structure in the phase portrait, i.e. the state of bi-attractors (attracting basins) is described. The evolving process of dynamic behaviour and flow fields are given. The theories are compared with some numerical simulations conducted by the authors. Besides, some verifiable experi-mental results are cited. The agreement between them is very well.

关键词： physical analysis numerical simulation pitching oscillation rocking motion bifurcation

Thermal Shock Property of Al/Ni-ZrO2.Gradient Thennal Barrier Coatings

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材料热处理学报 2004年第5期 974-976页

作者： FAN Jin-juan1, WANG Quan-sheng2. ZHANG Wei-fang1 1. Failure analysis center of {2. Institute of Aeronautical Materials, {2., china 2.Department of material science and engineering, {2. Institute of Technology, {2., china

Al/Ni-ZrO2.gradient thennal barrier coatings are made on aluminum substrate using plasma spraying method and one direction thermal shock properties of the coatings are studied in this paper. The results show that pores in coatings link to form cracks vertical to coating surface. They go through the whole ZrO2.coating once vertical cracks form. When thermal shock cycles increase, horizontal cracks that result in coatings failure forms in the coatings and interface. And vertical cracks delay appearance of horizontal cracks and enhance thermal shock property of coatings. Failure mechanisms of coating thermal shock are discussed using experiments and finite element method.

关键词： gradient thermal barrier coatings one direction shock finite element method