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Interaction Theory of Asphalt and Rubber

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Journal of Wuhan University of Technology(Materials Science) 2010年第5期25卷 853-855页

作者：高英 Transportation School Southeast University

Through scanning electron microscope （SEM）, spectral analysis, and component analysis tests, the interaction theory between asphalt and rubber was discussed. It is concluded that rubber powder become soft and bond together with each other after being mixed with asphalt. The asphalt changes from a smooth homogeneous matter to a continuous mixing system which is composed of rubber powder and asphalt. The interaction is mainly physical diffusion, but there are some chemical reactions in the process, especially at long reaction time.

关键词： crumb rubber asphalt rubber interaction theory physical diffusion chemical reactions

Sand-dust storms in china: temporal-spatial distribution and tracks of source lands

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Journal of Geographical Sciences 2001年第3期11卷 253-260页

作者： QIU Xin-fa1, ZENG Yan2. MIAO Qi-long2.(1. Urban & Resource Department, nanjing University, nanjing 2.0009,{2. 2. Department of Environmental Science, nanjing institute of meteorology, nanjing 2.0044,{2.) Urban Resource Department Nanjing University Department of Environmental Science Nanjing Institute of Meteorology

Sand-dust storm is a special natural disaster that frequently occurs in deserts and their surrounding areas. With the data published onSurface Meteorological Monthly Bulletin andSurface Chart during 1971–1996, the temporal-spatial distribution and annual variation of sand-dust storms are analyzed on the basis of the case study of atmospheric processes. Furthermore, the tracks and source areas of sand-dust storms are determined with the aid of GIS. The results show that except some parts of Qinghai Province and Inner Mongolia as well as Beijing, sand-dust storms decrease apparently in time and space in recent decades in china. Sand-dust storms occur most frequently in spring, especially in April. According to their source areas, sand-dust storms are classified into two types, i.e., the inner-source and outer-source sand-dust storms. Most of the outer-source sand-dust storms move along the north and west tracks. The north-track outer-source sand-dust storms always intrude into china across the Sino-Mongolian border from Hami, a city in the eastern part ofXinjiang, to Xilin Gol, a league in Inner Mongolia, while the west-track ones intrude into china from both southern and northern Xinjiang. The source lands of inner-source sand-dust storms concentrate in the Taklimakan Desert and its surrounding areas in southern Xinjiang, southern part of the Junggar Basin in north of Xinjiang, the Hexi Corridor in western Gansu Province, the dry deserts of Inner Mongolia and the Qaidam Basin in Qinghai.

关键词： sand-dust storm temporal-spatial distribution tracks source lands

Crystal structure and single crystal EPR of (NH_4)_2.15-crown-5)_3[Cu(mnt)_2. and (NH_4)_2.benzo-15-crown-5)_4[Cu(mnt)_2.·0.5H_2.

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Science china Chemistry 2007年第5期50卷 607-613页

作者： SUI YunXia1, WEN LiLi2. ZHANG Huan3 & MENG QingJin2.1 Center of Modern Analysis, nanjing University, nanjing 2.0093,{2. 2.State Key Laboratory of Coordination Chemistry, Coordination Chemistry institute, nanjing University, nanjing 2.0093,{2. 3 Jiangnan institute of Computing Technology, Wuxi 2.4083,{2. Center of Modern Analysis Nanjing University Nanjing China State Key Laboratory of Coordination Chemistry Coordination Chemistry Institute Nanjing University Nanjing China Jiangnan institute of Computing Technology Wuxi China

The X-ray crystal structures of (NH4)2.15-crown-5)3[Cu(mnt)2. (1) and(NH4)2.benzo-15-crown-5)4-[Cu(mnt)2. ident to 0.5H2. (2. were *** single crystals arecomposed of distinct structures of ammonium-crown ether supramolecular cation and [Cu(mnt)2.^(2.)*** triple-decker dication in complex 1 and a sandwich dimmer in complex 2.wereobserved.X-Band EPR studies on the single crystals of both complex 1 and complex 2.have been carriedout at room temperature,which revealed that complex 2.showed a perfect hyperfine structure of Cuwhereas that of complex 1 could not be *** principal values and direction cosines of theprincipal axes of the g and A tensors were computed by a least-squares fitting *** spindensity of Cu(ll) was estimated according to the principal values of the A tensors and compared wellwith the results calculated based on DFT method.

关键词： supramolecular cation, H-bonding interaction, EPR, g and A tensors, DFT

Study on design pressure of in-service welding pipes

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Science china(Technological Sciences) 2006年第4期49卷 434-444页

作者： XUE Xiaolong1, ZHU Jiagui2.& SANG Zhifu1 1. College of Mechanical and Power Engineering, nanjing University of Technology, nanjing 2.0009,{2. 2. nanjing Yangzi Petrochemical Maintenance and Installation Co. Ltd., nanjing 2.0048,{2. College of Mechanical and Power Engineering Nanjing University of Technology Nanjing China nanjing Yangzi Petrochemical Maintenance and Installation Co. Ltd. Nanjing China

A method of predicting design pressure and burn-through of in-service welding pipes was established. Temperature distributions of in-service welding under variable parameters were simulated by FEM. The effect of flowing of internal media was regarded as forced convection. Based on the numerical results, design pressure of the pipe can be obtained and burn-through can be predicted. It can be concluded that the design pressure decreases with the increasing of heat input. RSF and design pressure of the pipe increase with the increasing of flow rate. There is a range in which the increase changes greatly. For in-service welding, the range should be considered adequately to determine operating condition optimally. RSF increases with the increasing of pipe wall thickness. While the thickness increases to an extent, RSF shows little increase. Accord- ing to the curves of design pressure versus different parameters, safe working pressure can be achieved.

关键词： in-service welding, heat input, flow rate, pipe wall thickness, design pressure.

Research on the evaluation model of the modernization level of urban construction in Jiangsu Province,china

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Science china(Technological Sciences) 2010年第9期53卷 2510-2514页

作者： YANG JunYan1 & CHEN Wen2.1 School of Architecture,Southeast University,nanjing 2.0096,china 2.nanjing institute of Geography and Limnology,Chinese Academy of Sciences,nanjing 2.0008,china School of Architecture Southeast University Nanjing China nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing China

The modernization of urban construction is a key index in the process of urbanization,and also is an important index to measure the level of socio-economic and cultural *** paper analyzes and explores the related concepts of modernization of urban construction,analyzes the situation and identity of urban construction layer by layer so as to establish an evaluation index system of the modernization level of urban construction and then the paper evaluates the modernization level of urban construction from four different angles,which are the perspectives of the urban planning control,the level of urban facilities,urban management,urban construction *** later analyzes the evaluation results by choosing Jiangsu Province as a research hierarchy from the scale chains of urban study and makes efforts to the operative and directive development direction.

关键词： modernization of urban construction index system evaluation model

New species and new records of diatoms from Lake Fuxian,china

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Journal of Systematics and Evolution 2010年第1期48卷 65-72页

作者： 1 Yan-Ling LI 1 Zhi-Jun GONG 2.Chun-Chao WANG 1 Ji SHEN 1(State Key Laboratory of Lake Science and Environment,nanjing institute of Geography and Limnology,Chinese Academy of Sciences,nanjing 2.0008,china) 2.nanjing institute of Geology and Palaeontology,Chinese Academy of Sciences,nanjing 2.0008,china) (State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China) (nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China)

One new species,four newly recorded genera,and two newly recorded species of diatoms are described from *** are Sellaphora fuxianensis ***,Sellaphora Mereschkowsky,Karayevia Round & Bukhtiyarova,Placoneis Mereschkowsky,Fallacia Stickle & Mann,Placoneis prespanensis Levkov,Krstic & Nakov,and Fallacia lucinensis(Hustedt) *** taxa were collected from Lake Fuxian in Yunnan Province,*** species were observed with light and scanning electron microscopes,and their taxonomic characters are discussed.

关键词： china diatom new records new species.

Comparing logic coverage criteria on test case prioritization

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Science china(Information Sciences) 2012年第12期55卷 2826-2840页

作者： FANG ChunRong 1,2.CHEN ZhenYu 1,2.& XU BaoWen 1 1 State Key Laboratory for Novel Software Technology,nanjing University,nanjing 2.0093,{2. 2.Software institute,nanjing University,nanjing 2.0093,{2. State Key Laboratory for Novel Software Technology Nanjing University Nanjing China Software institute Nanjing University Nanjing China

Logic coverage criteria have been widely used in the testing of safety-critical *** the past few years,fault-based logic coverage criteria have been studied intensively both in theory and in ***,there is a lack of authentic evidence of the comparison of fault-based logic coverage criteria with other logic coverage criteria,such as branch coverage and modified condition/decision coverage(MC/DC).In this paper,we present a comprehensive empirical study that compares these logic coverage criteria on test case prioritization,which is currently a hot topic in software *** useful conclusions are drawn from our research:(1) Fine-grained coverage criteria are always more effective and efficient.(2. The effectiveness of fault-based logic coverage criteria is not significantly different from that of MC/DC in terms of statistics,but the former is more stable.(3) A random strategy is more effective than branch coverage if a certain number of test cases are redundant.

关键词： fault detection capability logic coverage fault-based testing test case prioritization

Geochemical simulation of the formation of brine and salt minerals based on Pitzer model in Caka Salt Lake

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Science china Earth Sciences 2004年第8期47卷 720-726页

作者： LIU Xingqi1, CAI Keqin2.& YU Shengsong3 1. nanjing institute of Geography and Limnology, Chinese Academy of Sciences, nanjing 2.0008, china 2. china University of Geosciences, Beijing 100083, china 3. institute of Salt Lakes, Chinese Academy of Sciences, Xining 810008, china nanjing institute of Geography and Limnology Chinese Academy of Sciences Nanjing China china University of Geosciences Beijing China institute of Salt Lakes Chinese Academy of Sciences Xining China

The geochemical simulation of the formation of brine and salt minerals based on Pitzer model was made in Caka Salt Lake. The evolution of the mixed surface-water and the mineral sequences were calculated and compared with the hydrochemical compositions of the brine and the salt minerals of the deposit in Caka Salt Lake. The results show that the formation temperature of the lake is between 0°C and 5°C, which is well identical with other studies. The mixing of salt-karst water with the surface waters, neglected by the former researchers, is very important to the formation of the lake, indicating that the initial waters resulting in the formation of the lake are multi-source. It is the first time to use Pitzer model in china for making geochemical simulation of the formation and evolution of inland salt lake and satisfactory results have been achieved.

关键词： Pitzer model,Caka Salt Lake,geochemical simulation,salt-karst water.

Reducing component estimation for varying coefficient models with longitudinal data

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Science china Mathematics 2008年第2期51卷 250-272页

作者： TANG QingGuo~(1,2.) WANG JinDe~2.1 institute of Sciences,People’s Liberation Army University of Science and Technology,nanjing 2.0007,{2. 2.Department of Mathematics,nanjing University,nanjing 2.0093,{2. institute of Sciences People’s Liberation Army University of Science and Technology Nanjing China Department of Mathematics Nanjing University Nanjing China

Varying-coefficient models with longitudinal observations are very useful in epidemiology and some other practical *** this paper,a reducing component procedure is proposed for es- timating the unknown functions and their derivatives in very general models,in which the unknown coefficient functions admit different or the same degrees of smoothness and the covariates can be time- *** asymptotic properties of the estimators,such as consistency,rate of convergence and asymptotic distribution,are *** asymptotic results show that the asymptotic variance of the reducing component estimators is smaller than that of the existing estimators when the coefficient functions admit different degrees of *** sample properties of our procedures are studied through Monte Carlo simulations.

关键词： varying coefficient model longitudinal data nonparametric estimation reducing component estimators asymptotic normality 62.07