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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 210093.{3. 2 State Key Laboratory of Coordination Chemistry, Coordination Chemistry institute, nanjing university, nanjing 210093.{3. 3.Jiangnan institute of Computing technology, Wuxi 214083.{3. 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 0.5H2O (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

A general model for estimating actual evaporation from non-saturated surfaces

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Journal of Geographical sciences 2002年第4期12卷 479-484页

作者： QIU Xinfa1,2, ZENG Yan3. LIU Changming3.1. Dept. of Urban && Resource science, nanjing university, nanjing 210093. china 2. Dept. of Geography, nanjing institute of meteorology, nanjing 210044, china 3. Inst. of Geographic sciences and Natural Resources Dept. of Urban & Resource science Nanjing University Nanjing China Dept. of Geography Nanjing Institute of Meteorology Nanjing China Inst. of Geographic sciences and Natural Resources Research CAS Beijing China

Based on energy balance equation and mass transfer equation, a general model to estimate actual evaporation from non-saturated surfaces was derived. Making use of two concepts, “relative evaporation” and “relative drying power”, a relationship was established to account for the departure from saturated conditions. Using this model, the actual evaporation (evapotranspiration) can be calculated without the need of potential evaporation estimation. Furthermore, the model requires only a few meteorological parameters that are readily and routinely obtainable at standard weather stations. Based on nearly 3. years data of 43. meteorological stations and 512 hydrological stations in china, in combined with GIS, nine typical river basins were selected. Using the data of the selected river basins, the model was tested. The results show that the actual evaporation rate can be estimated with an error of less than 10% in most areas of china, except few years in the Yellow River Basin.

关键词： potential evaporation actual evaporation

Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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science china Earth sciences 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2, TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. nanjing institute of Geology and Palaeontology, Chinese Academy of sciences, nanjing 210008, china 2. Henan institute of Geological Survey, Zhengzhou 450007, china 3. State Key Laboratory of Geological Processes and Mineral Resources at china university of Geosciences, Wuhan 43.074, china 4. Faculty of Material sciences and Chemical Engineering, china university of Geosciences, Wuhan 43.074, china nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China Henan institute of Geological Survey Zhengzhou China State Key Laboratory of Geological Processes and Mineral Resources at china university of Geosciences Wuhan China Faculty of Material sciences and Chemical Engineering China University of Geosciences Wuhan China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

Distribution characteristics of terrestrial heat flow density in Jiyang depression of Shengli Oilfield, East china

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science china Earth sciences 2004年第9期47卷 804-812页

作者： GONG Yuling1,2, WANG Liangshu1, LIU Shaowen1, LI Cheng1, HAN Yongbing1, LI Hua1, LIU Bo1 & CAI Jingong3.1. Department of Earth sciences, nanjing university, nanjing 210093. china 2. Department of Exploration and Information technology of East china institute of technology, Fuzhou 3.4000, china 3. Earth science Institution of Shengli Oilfield, Dongying 257015, china Department of Earth sciences Nanjing University Nanjing China Department of Exploration and Information technology of East china institute of technology Fuzhou China Earth science Institution of Shengli Oilfield Dongying China

Based on the geo-temperature data of 13.systematically continuous temperature log curves and 700 testing oil boreholes in Jiyang depression, Shengli Oilfield, and the measured thermal conductivities of 47 rock samples, the terrestrial heat flow densities of 114 boreholes of Jiyang depression and its surrounding areas are determined, including 13.of those data derived from systemically continuous temperature logging. The results show that Jiyang depression has a relatively high background heat flow with an average value (65.8 5.4) mW/m2. The lateral variation of heat flow in basin has negative correlation with basement depth. Moreover, heat flow of uplift areas with shallower basement is high, so are those of regions with volcanic rocks, and those of depression areas with deep basement are relatively low. The heat flow densities of different structural units of Jiyang depression can be summarized as follows: The average heat flow value of Zhanhua sag is (67.4 5.3. mW/m2, higher than that of the whole basin, that of Dongying sag is (66.0 6.1) mW/m2, and that of Chezhen sag is (65.1 3.7) mW/m2. It is apparent that these latter two values are approximate to the average value of the whole Jiyang depression, while the average value of Huimin sag is (63.65.0) mW/m2, lower than that of the whole basin. In fact, the basement depth and the distribution framework of uplift and depression areas are all controlled by the process of lithosphere extension. In addition, the distribution of volcanic rocks in basin is also relatively close to this extension geodynamic process. In summary, the distribution characteristics of terrestrial heat flow of Jiyang depression is determined by the Cenozoic tectono-thermal events of this region.

关键词： Jiyang depression, terrestrial heat flow, thermal conductivity.

SENSITIVE NUMERICAL SIMULATION AND ANALYSIS OF RAINSTORM USING NESTED WRF MODEL

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Journal of Hydrodynamics 2006年第5期18卷 578-586页

作者： WANG Shu-chang HUANG Si-xun LI Yi institute of meteorology PLA University of Science and Technology Nanjing 211101 China

Nowadays, the nested grid model is widely used to increase the resolution of numerical model. An attempt to investigate the influence of the newly developed nesting technique of WRF model on the mesoscale numerical simulation of severe storm is described in this article. The results of sensitivity tests infer that the WRF model give more accurate and vivid prediction of severe storm with nesting scheme. As is shown in the tests, simulating value of the precipitation centers using nesting scheme are larger than those without using nesting scheme, which indicates that the simulating precipitation of nested storm is closer to the real rainfall. And there is obvious improvement of distribution of rain area and position of precipitation centers. According to the high resolution output data of the WRF model, deep and detailed analysis of characters of the mesoscale system that triggers the rainstorm is reported in this article, and the thermal and dynamical characters of this Meiyu front severe storm are also discussed.

关键词： WRF nesting numerical simulation mesoscale analysis

Seismic wave propagating in Kelvin-Voigt homogeneous visco-elastic media

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science china Earth sciences 2006年第2期49卷 147-153页

作者： YUAN Chunfang1, PENG Suping1, ZHANG Zhongjie2 & LIU Zhenkuan3.1. china university of Mining & technology, Beijing 100083. china 2. institute of Geophysics, Chinese Academy of sciences, Beijing 100101, china 3. Exploration and Development Research institute of Daqing Oilfield, Daqing 163.12, china china university of Mining & technology Beijing China institute of Geophysics Chinese Academy of Sciences Beijing China Exploration and Development Research institute of Daqing Oilfield Daqing China

This paper studies, under a small disturbance, the responses of seismic transient wave in the visco-elastic media and the analytic solution of the corresponding third-order partial differential equation. A plane wave solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differ-ential equation with a pulse source is obtained. By the principle of pulse stacking of particle vibration, the result is extended to the solution of Kelvin-Voigt homogeneous visco-elastic third-order partial differential equation with any source. The velocities of seismic wave propagating and the attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are discussed. The velocities of seismic wave propagating and the coefficient of attenuation of seismic wave in Kelvin-Voigt homogeneous visco-elastic media are derived, expressed as functions of density of the media, elastic modulus and visco-elastic coefficient. These results can be applied in inversing lithology parameters in geophysical prospecting.

关键词： Kelvin-Voigt visco-elastic velocity attenuation seismic wave.

Approximation of dense-n/2-subgraph and table compression problems

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science china Mathematics 2005年第9期48卷 1223-1233页

作者： XU Dachuan~1 HAN Jiye~2 & DU Dongle~3.1. College of Applied sciences,Beijing university of technology,Beijing 100022,{3. 2. institute of Applied Mathematics,Academy of Mathematics and Systems science,Chinese Academy of sciences,Beijing 100080,{3. 3. Faculty of Administration,university of New Brunswick,P.O.Box 4400,Fredericton,NB E3. 5A3.Canada College of Applied sciences Beijing University of Technology Beijing 100022 China institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Faculty of Administration University of New Brunswick P.O. Box 4400 Fredericton NB E3B 5A3 Canada

We develop improved approximation algorithms for two NP-hard problems: the dense-n/2-subgraph and table *** on SDP relaxation and advanced rounding techniques,we first propose 0. 5982 and 0. 5970-approximation algorithms respec- tively for the dense-n/2-subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 6243.and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP *** results for TCP beat the 0. 5 bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way.

关键词： dense-n/2-subgraph problem(DSP) table compression problem(TCP) SDP approximation ratio

Determination of the Thermal Expansion Coefficient of Concrete at Early Ages by Using Temperature-stress Testing Machine

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Journal of Wuhan university of technology(Materials science) 2006年第4期21卷 146-149页

作者：霍凯成 Hubei Key Laboratory of Roadway Bridge & Structure Engineering Wuhan University of TechnologyWuhan 430070China

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved ： temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolation process should be taken into consideration in the same time. Proper chemical admixtures and mineral cornpasitions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

关键词： concrete coefficient of thermal expansion temperature-stress test

Communication network designing:Transmission capacity,cost and scalability

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science china(Information sciences) 2012年第11期55卷 2454-2465页

作者： ZHANG GuoQiang1,2,3.& ZHANG GuoQing1 1institute of Computing technology,Chinese Academy of sciences,Beijing 100190,{3. 2School of Computer science and technology,nanjing Normal university,nanjing 210046,{3. 3.rovincial Key Laboratory for Computer Information Processing technology,Soochow university,Suzhou 215000,{3. institute of Computing technology Chinese Academy of Sciences Beijing China School of Computer science and technology Nanjing Normal University Nanjing China Provincial Key Laboratory for Computer Information Processing technology Soochow University Suzhou China

Despite the growing number of works centering around the traffic dynamics on complex networks,these researches still have some common shortcomings,e.g.,too simple traffic flow model and lack of considerations for the designing cost and scalability *** paper builds on a more realistic traffic flow model,and offers a holistic view on the network designing *** addition to the extensively studied transmission capacity,this paper takes designing cost and scalability as two other designing objectives,and presents a quantitative study of how different designing choices independently and collectively influence these objectives by the introduction of a cartesian coordinate *** is shown that different kinds of network topologies display different shapes of achievable solution spaces and exhibit different abilities to achieve cost-effective and scalable *** particular,we find the philosophy underlying empirical network designing and engineering today fails to meet the cost-effective and scalable designing requirements,and propose a cost-effective and scalable designing scheme for BA-like networks,i.e.,the efficient routing combined with effective betweenness based link bandwidth *** addition,when designing a thoroughly new network from the beginning,we find that ER network is a good candidate to achieve cost-effective and scalable designing in most settings.

关键词： cost-effective communication network designing network transmission efficiency network topology traffic dynamics next generation network scalable network designing

Ca^(2+) signals induced from calcium stores in pancreatic islet β cells

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Chinese science Bulletin 2000年第1期45卷 51-56页

作者： ZENG Xuhui, QU Anlian, LOU Xuelin, XU Jianhua, WANG Junjian, WU Hongxiu & ZHOU Zhuan1. institute of Biochemistry and Biophysics, Huazhong university of science and {3., Wuhan 43.074, china 2. Pharmacology, Huazhong university of science and {3., Wuhan 43.074, china 3. School of Life sciences, university of science and {3. of china, Hefei 23.027, china Correspondence should be addressed to Zhou Zhuan. institute of Biochemistry and Biophysics Huazhong University of Science and Technology Wuhan China Pharmacology Huazhong University of Science and Technology Wuhan China School of Life sciences University of Science and Technology of China Hefei China

In single rat pancreatic βcells, using fura-2 microfluorometry to measure [Ca2+] response upon different stimuli, the ways of calcium regulation have been studied. When the extracellular calcium concentration was 2.5 mmol/L, either 60 mmol/L KCI, 20 mmol/L D-glucose or 0.1 mmol/L tolbutamide induced increase in [Ca2+]. Such increase in [Ca2+] was absent when the same stimuli were applied under zero extracellular calcium. These results indicate that the increase of [Ca2+] is induced by the activation of voltage-dependent calcium channels in p celis. The manifold forms of [Ca2+] change induced by glucose imply that the effects of glucose are complex. 5 mmol/L caffeine or 5 mmol/L MCh increase the [Ca2+], which is independent of the external calcium, suggesting that [Ca2+] can be regulated by Ca2+ release from not only the IP3.sensitive but also the ryanodine sensitive calcium stores in p celis. The latency of Ca responses for IP3.pathway (5 s) is faster than that for ryanodine pathway (3. s), it is

关键词： pancreatic β cell [Ca2+]i calcium stores glucose fura-2.