检索结果-南通市图书馆

Study on the two and three-parameter working stability regions of 3.-TZP suspension

在线全文

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2. ZHANG Xinni3. CHEN Sha’ou3.& QI Ping3.1. Department of Chemistry, Qingdao university, Qingdao 2.6071, china 2. Department of Chemistry, Tsinghua university, {3. 100084, china 3. Department of Physics, Qingdao university, Qingdao 2.6071, china Department of Physics Qingdao University

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3.-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3.-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3.-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3.-TZP, suspension, stability, DLVO theory, interparticle potential energy.

Teleconnection between the Indian summer monsoon onset and the Meiyu over the Yangtze River Valley

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2008年第7期51卷 1021-1035页

作者： LIU YunYun1,2.3.& DING YiHui2.1 Chinese Academy of Meteorological sciences, {2. 100081, china 2.National Climate Center, {2. 100081, china 3.graduate university of Chinese Academy of sciences, beijing 100049, china Chinese Academy of Meteorological sciences Beijing China National Climate Center Beijing China graduate university of Chinese Academy of {2. Beijing China

Based on the Indian and Chinese precipitation data and the NCEP-NCAR reanalysis circulation data, the relationship between the Indian summer monsoon (ISM) onset and the Meiyu over the Yangtze River Valley has been discussed by the methods of correlation analysis and composite analysis. The results show that the date of ISM onset over Kerala in the southwestern coast of the Indian Peninsula is about two weeks earlier than the beginning of the Meiyu over the Yangtze River Valley. After the outbreak of ISM, the teleconnection mode sets up from the western coast of India via the Bay of Bengal (BOB) to the Yangtze River Valley and southern Japan. It is different both in time and space from the telecon- nection mode which is from the northwest of India via the Tibetan Plateau to northern china. The for- mer mode is defined as the "south" teleconnection of the Asian summer monsoon, forming in the pe- riod of ISM onset; while the latter mode is called the "north" teleconnection, mainly occurring in the Asian monsoon culminant period. During the process of the "south" teleconnection’s formation, the Asian monsoon circulation has experienced a series of important changes: ISM onset, the northward movement of the south Asia high (SAH), the onset vortex occurrence, the eastward extension of the stronger tropical westerly belt, and the northeastward jump of the western Pacific subtropical high (WPSH), etc. Consequently, since ISM sets up over Kerala, the whole Asian continent is covered by the upper SAH after about two weeks, while in the mid- and lower troposphere, a strong wind belt forms from the Arabian Sea via the southern India, BOB and the South china Sea (SCS), then along the western flank of WPSH, to the Yangtze River Valley and southern Japan. With the northward moving of the subtropical jet streams, the upper westerly jet stream and the low level jet have been coupled ver- tically over east Asia, while the Yangtze River Valley happens to locate in the ascending motion

关键词： Indian summer monsoon (ISM) the Meiyu over the Yangtze River Valley teleconnection mode

The role of aerial algae in the formation of the landscape of the Yunnan Stone Forest,Yunnan Province, china

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2004年第9期47卷 846-864页

作者： TIAN Youping1,3. ZHANG Jie2. SONG Linhua1 & BAO Haosheng2.1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101,{3. 2. Department of Geography, Nanjing university, Nanjing 2.0093.{3. 3. School of Earth sciences and Resources,{3. university of Geosciences, beijing 100083.{3. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China School of Earth sciences and Resources China University of Geosciences Beijing China Department of Geography Nanjing University Nanjing China

Aerial algae on the surface of carbonate rocks at the Stone Forest, Shilin County, Yunnan Province, china, and their bioerosion were investigated in the field and studied in the laboratory in detail. Through the observation, identification and statistics of more than one hun- dred algal samples and rock samples with the optical microscopes (stereomicroscope, biological microscope) and the scanning electronic microscope (SEM), the relationships between erosional forms on the surface of the Stone Forest and algae and/or algal communities and the genetic mechanism for the formation of erosional forms were analyzed. It is suggested that aerial algae play an active role in bioerosive processes that may affect the formation of karst erosional forms. These effects include both direct and indirect ones. The direct effect is the initiative control (algal shape-controlling role) of algae on the formation of karst forms of various scales, mostly mi- cro-scale (3.) and minor-scale (10-3.10-1m) erosional forms. The algal shape-controlling roles can be divided into the algal individual shape-controlling role and the algal community shape-controlling role. The former mostly controls the formation of micro-scale erosional forms, while the latter mostly controls the formation of micro-scale and smaller minor-scale erosional forms. The indirect effect refers to the promoting role of algae in the formation of karst forms, which may affect the formation of karst forms of all types and scales. The bioerosion of algae accelerates the weathering process of the whole Stone Forest karst landforms.

关键词： aerial algae, bioerosion, the Stone Forest, Yunnan Province, china.

A 12.bit multichannel ADC for pixel detectors in particle physics and nuclear imaging

在线全文

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2010年第5期53卷 1208-1214页

作者： WEI Wei1,2.3.WANG Zheng1,3.& ZHAO JingWei1,3.1 Institute of High Energy Physics,Chinese Academy of sciences,beijing 100049,{3. 2.graduate university of Chinese Academy of sciences,beijing 100049,{3. 3.Key Lab of Nuclear Detection Technology and Nuclear Electronics of Chinese Academy of sciences,beijing 100049,{3. Institute of High Energy Physics Chinese Academy of Sciences graduate university of Chinese Academy of {2. Key Lab of Nuclear Detection Technology and Nuclear Electronics of Chinese Academy of sciences

Modern pixel detectors in nuclear and particle physics experiments and also in nuclear imaging,starve for highly integrated application specified integrated circuit(ASIC),whereas in china the study of ASIC still stays far away from practical *** lack of ASIC strictly limits the research and development of domestic high energy physics field.A 12.bit multichannel ADC designed for high density readout is introduced as a major candidate for solution.A precise model is discussed and the simulation fully agrees with the model,which indicates a key principle of *** is performed according to the given rule,and novel layout techniques are carried *** results in all aspects are also obtained,showing an excellent real performance,which satisfies the practical requirement.

关键词： application specified integrated circuit high density readout Wilkinson ADC multi-channel ADC

Effect of rock mass structure and block size on the slope stability——Physical modeling and discrete element simulation

在线全文

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2005年第z1期48卷 1-17页

作者： LI Shihai1, LIAN Zhenzhong1,2.& J. G. Wang3.1. Institute of Mechanics, Chinese Academy of sciences, {2. 100080, china 2. {3. School, Chinese Academy of sciences, {2. 100060, china 3. Tropical Marine Science Institute, National university of Singapore, Singapore 1192.0 Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China graduate School Chinese Academy of Sciences Beijing 100060 China Tropical Marine Science Institute National University of Singapore Singapore 119260 Singapore

This paper studies the stability of jointed rock slopes by using our improved three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, joints configuration effect, limit equilibrium method.

Modeling and verifying Web services driven by requirements:An ontology-based approach

在线全文

学校读者我要写书评

暂无评论

Science in china(Series F) 2006年第6期49卷 792-820页

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

在线全文

学校读者我要写书评

暂无评论

Wuhan university Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. LIU Chuang1, 3.1. Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101,{3. 2. graduate university of Chinese Academy of sciences, beijing 100049,{3. 3. College of Resources Science and Technology, beijing Normal university, beijing 100875,{3. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate university of Chinese Academy of {2. Beijing China College of Resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993.the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the china-Brazil earth resources satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993.to 2.08. There were 12.63..54 hm2.cropland de-creased between 1993.and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the china-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

Cotton pixel identification with CBERS-02.CCD data based on spectral knowledge

在线全文

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2005年第S2期48卷 129-144页

作者： LI Jing1,2.3. LIU Qinhuo1,3. LIU Qiang1, CHEN Liangfu1, BO Junhua3.& LI Shaokun3.1. State Key Laboratory of Remote Sensing Science, IRSA, Chinese Academy of sciences, beijing 100101, china 2. {3. university of Chinese Academy of sciences, beijing 100049, china 3. The Key Oasis Eco-agriculture Laboratory of Xinjiang Production and Construction Corps, Shi Hezi 83.000, china State Key Laboratory of Remote Sensing Science IRSA Chinese Academy of Sciences graduate university of Chinese Academy of {2. The Key Oasis Eco-agriculture Laboratory of Xinjiang Production and Construction Corps

In this paper the in-situ experiment data are collected from the Spectral Library to estimate the possible values of the primary structural parameters in each cotton growing season by statistics. Based on these values the spectra of the cotton major growing seasons were simulated and analyzed using the canopy reflectance model, SAILH. In this way we also simulated the cotton pixel spectra corresponding to CBERS-02.CCD and took them as the reference spectra for spectra fitting. Then No.143.Regiment of No.8 Agricultural Division of Xinjiang Production and Construction Corps (XPCC) was chosen as the study area, and two spectra fitting methods, Mahalanobis distance and spectra angle, were used to identify cotton pixel from CBERS-02.CCD image of the study area. At last we analyzed the effect of the calibration coefficients error on cotton identifying. The results showed that within 4% error the spectral angle classifier can still have a good performance.

关键词： CBERS-02 cotton pixel identification spectra fitting.

Zhang-Xuan thermal uplift and its genesis

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2005年第8期15卷 725-732页

作者： SHAO Ji'an1*, NIU Shuyin2. ZHANG Lüqiao3.and LI Hongyang2.1. School of Earth and Space sciences, Peking {2., beijing 100871,{3. 2. Shijiazhuang {2. of Economics, Shijiazhuang 05003.,{3. 3. Geological Bureau of Inner Mongolia, Huhhot 01002.,{3.) School of Earth and Space sciences Peking University Beijing 100871 China. Shijiazhuang university of Economics Shijiazhuang 050031 China. Geological Bureau of Inner Mongolia Huhhot 010020 China

Based on the researches of the Mesozoic thermal evolution history, the deformed structures, and fission track analysis of the Zhangjiakou-Xuanhua area, we obtained the following knowledge: the area experienced in 140 Ma an underplating which is marked by emplacement of mantle derived magma; during 13.—110 Ma a series of eruptions and intrusions happened, and during 80—10 Ma a rising process occurred which is synchronous with the adjacent Taihang and Yanshan Mountains and was accompanied by a series of structures down slipping from the just formed Zhang-Xuan uplift toward its periphery. Combining the Zhang-Xuan thermal lift with the large detachment structure in Baoding depression of the North china Basin in the Late Mesozoic confirms that an even larger extensional tectonic background existed in North china during this period.

关键词： Zhang-Xuan area underplating thermal uplift fission track extensional structure.