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Environmental characteristics of Mid-Holocene recorded by lacustrine sediments from Lake Daihai, north environment sensitive zone, china

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science china Earth sciences 2006年第9期49卷 968-981页

作者： SUN Qianli1,2, ZHOU Jie1, SHEN Ji3. CHEN Peng1,2, WU Feng1,2 & XIE Xiuping1,2 1. State Key Lab of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2. Graduate University of Chinese Academy of sciences, Beijing 10003., china 3. nanjing Institute of Geography and Limnology, Chinese Academy of sciences, nanjing 210008, china State Key Lab of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of Chinese Academy of sciences Beijing China nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing China

Climate proxies, such as total organic carbon and nitrogen (TOC, TN), carbonate content (CaCO3., grain-size and pollen of the sediment core retrieved from enclosed Lake Daihai which lies in the north china environment sensitive zone are analyzed to reconstruct the environment evolution of the area based on high-resolution radiocarbon chronology. The results reveal that the TOC and TN contents of the sediments correlate well with pollen percentage and pollen flux variations during the Holocene, and both reach their peak values simultaneously at 6.7―3.5 ka BP (calendar age, 7.6―3.6 ka BP). Since 6.7 ka BP, both the CaCO3.and organic matter contents of the core have simultaneous variations, and their high values also occur during 6.7―3.5 ka BP. While during 9.0―6.7 ka BP (calendar age, 10―7.6 ka BP) relatively lower level of organic matter content and pollen flux corre- spond to the higher level of carbonate content. The above relations suggest that during 6.7―3.5 ka BP, the productivity and effective precipitation were greatly improved in the lake drainage area, and this would probably strengthen the hydrodynamic conditions, enhancing organic matter, pollen and carbonate inputs from terrestrial sources. Such processes would account for the enrichment of both organic matter and carbonate in the sediments. While during 9.0―6.7 ka BP, the lower level of or- ganic matter, pollen flux but high carbonate content show depressed productivity and declined vege- tation coverage. The higher carbonate content at this stage would have probably resulted from the higher evaporation ratio of the lake water under relatively drier climate conditions. Therefore, it is in- ferred that during 6.7―3.5 ka BP, the climate was more humid with abundant rainfalls and vegetation was more flourishing in the Lake Daihai area. This can be seen as Holocene Climate Optimum (HCO). As a result, this has evident discrepancies with the traditional notion that the HCO occurs at Early Holocene or early Mid

关键词： Lake Daihai, Mid-Holocene, lacustrine sediments, environmental characteristics.

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The microbial metallogeny of weathering crust REE deposits in South china

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Chinese science Bulletin 1999年第S2期44卷 71-73页

作者： CHEN Binghui~(1,2), WANG Zhimei~3. HUANG Limei~3. WU Fuhai~3. CHEN Jingde~2 and XU Wenlie~2 1. department of Earth sciences, nanjing University,{3. 2. department of Earth sciences, Zhongshan University, Guangzhou 510275, china 3. Guangdong Pharmaceutical College, Guangzhou 510244, china department of Earth sciences Nanjing University Nanjing 210093 China department of Earth sciences Zhongshan University Guangzhou 510275 China Guangdong Pharmaceutical College Guangzhou 510244 China

VERY little is known about the roles of microorganisms in the metallogeny of weathering crust REE deposits, although there has been much literature on REE behavior in weathering conditions. The present note deals with the microorganisms in 4 weathering profiles of an REE deposit and their roles in migration and accumulation of REE in weathering conditions. 1 Cultivation and identification of microorganisms Under strict sterilization, samples were collected from various parts of 4 weathering profiles of granites in a weathering crust REE deposit in South china. The samples were then cultivated for microorganisms with ordinary agars as culture media and then the cultivated microorganisms were dyed and identifiedunder a microscope. The sampled positions and cultivated numbers of microbial colonies are shown

关键词： microbial metallogeny weathering crust REE deposit South china.

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Early Hydration of Composite Cement with Thermal Activated Coal Gangue

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Journal of Wuhan University of Technology(Materials science) 2010年第1期25卷 162-166页

作者：郭伟 department of Material Engineering Yancheng Institute of Technology Institute of Material science and Engineering Nanjing University of Technology

Composite cement samples were prepared by mixing clinker, gypsum with burnt coal gangues which was calcined at various temperatures. The mechanical strength and Ca（OH）2 content in the cement paste were tested, and the paste composition and microstructure were analyzed by thermogravimetry-differential thermal analysis （TG-DSC）, X-ray diffraction（XRD）, scanning electronic microscopy （SEM） and pore structure analysis. Results demonstrate that the thermal activated coal gangue could accelerate the early hydration of cement clinker obviously, which promotes the gangue hydration itself. The early hydrated products of the cement are C-S-H gel, Ca（OH）2 and AFt. The cement with 3.% （in mass） the gangue exhibits higher mechanical strength, and among all the cement samples the one with the gangue burnt at 700 ℃ displays the highest hydration rate, mechanical strength, the most gel pores and the lowest total porosity.

关键词： blended cement hydration microstructure hydration product

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A new heuristic algorithm for the circular packing problem with equilibrium constraints

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science china(Information sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2,LI Gang 3.& GENG HuanTong 1 1 School of Computer and Software,nanjing University of Information science & Technology,nanjing 210044,{3. 2 Network Information Center,nanjing University of Information science & Technology, nanjing 210044,{3. 3.School of Mathematics and Physics,nanjing University of Information science & Technology,nanjing 210044,{3. School of Computer and Software Nanjing University of Information Science & Technology Network Information Center Nanjing University of Information Science & Technology School of Mathematics and Physics Nanjing University of Information Science & Tec

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

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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,{3. 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.

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南京雨花台区创新打造“幸福三圈”持续提升民生服务水平

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社会与公益 2024年第7期 8-10页

作者： Social Work department of nanjing Yuhuatai District Committee of the Communist Party of china 中共南京市雨花台区委社会工作部

近年来,雨花台区坚持共建共治共享理念,聚焦群众迫切需求和民生领域短板,布局建设民生事业“幸福三圈”,即5分钟社区商业圈、10分钟文化体育圈、15分钟健康服务圈,推出一系列具有针对性的改革创新举措。该区推动基层社区协同高效治理,... 详细信息

近年来,雨花台区坚持共建共治共享理念,聚焦群众迫切需求和民生领域短板,布局建设民生事业“幸福三圈”,即5分钟社区商业圈、10分钟文化体育圈、15分钟健康服务圈,推出一系列具有针对性的改革创新举措。该区推动基层社区协同高效治理,公共服务优质均衡发展,群众幸福指数持续提升,先后获评全国群众体育先进单位、省义务教育优质均衡发展区、首批“江苏省社区医院示范区”,入选全国智慧健康养老示范基地。

关键词：民生服务雨花台区商业圈创新举措民生事业体育先进单位幸福指数社区医院

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Predicting the Maintainability of Open Source Software Using Design Metrics

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Wuhan University Journal of Natural sciences 2008年第1期13卷 14-20页

作者： ZHOU Yuming1,2, XU Baowen1,3.1. School of Computer science and Engineering, Southeast University, nanjing 210096, Jiangsu,china 2. {3. of Computing, Hong Kong Polytechnic University, Hong Kong, china 3. Jiangsu Institute of Software Quality, nanjing 210096, Jiangsu,china School of Computer science and Engineering Southeast University Nanjing China department of Computing Hong Kong Polytechnic University Hong Kong China Jiangsu Institute of Software Quality Nanjing China

This paper empirically investigates the relationships between 15 design metrics and maintainability of 148 Java open source software. The results show that size and complexity metrics are strongly related to the maintainability of open source software. However, cohesion and coupling, as currently captured by existing metrics, do not seem to have a significant impact on maintainability. When used together, these metrics can predict system maintainability fairly accurately （mean MREs below 3.%）.

关键词： open source: object-oriented maintainability metric prediction regression

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Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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science china Earth sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2, DING Yihui3.& ZHANG Renhe2 1. Jiangsu Key Laboratory of Meteorological Disaster (KLME), nanjing Institute of Meteorology, nanjing University of Informa- tion science and Technology, nanjing 210044, china 2. State Key Laboratory of Severe Weather (LaSW), Chinese Academy of Meteorological sciences, Beijing 100081, china 3. National Climate Center, Chinese Meteorological Administration, Beijing 100081, china Jiangsu Key Laboratory of Meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing China State Key Laboratory of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing China National Climate Center Chinese Meteorological Administration Beijing China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-china Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-china Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-china Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-china Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-china Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-china Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-china Peninsula to South china Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-china Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

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An analysis on the evolvement processes of lake eutrophication and their characteristics of the typical lakes in the middle and lower reaches of Yangtze River

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Chinese science Bulletin 2006年第13期51卷 1603-1613页

作者： CHENG Xiaoying1,2,3.& LI Shijie1 1. nanjing Institute of Geography & Limnology, Chinese Academy of sciences, nanjing 210008, {3. 2. The Key Laboratory of Industrial Biotechnology, Ministry of Educa- tion, Southern Yangtze University, Wuxi 21403., {3. 3. School of Biotechnology, Southern Yangtze University, Wuxi 21403., {3. nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China The Key Laboratory of Industrial Biotechnology Ministry of Education Southern Yangtze University Wuxi 214036 China School of Biotechnology Southern Yangtze University Wuxi 214036 China

According to the study on the aquatic environment of the typical lakes in the middle and lower reaches of Yangtze River, lake eutrophication is a process in which the lake ecosystem degenerates, resulting in the deterioration of the water quality due to the enrichment of the nutrients. Moreover, the succession of lake ecosystem and change of water quality both couple well with the evolvement of tro- phic state. Then the conceptual model is mentioned and ten lake states are classified. Based on these, the authors analyzed the eutrophication processes of the typical lakes in the middle and lower reaches of Yangtze River. The large lakes with taking in - send- ing out water typical of Poyang Lake evolve from State 1 before the 1980s into State 2 after the 1980s, the large and medium lakes typical of Taihu Lake evolve from State 1-2 in the 1960s into State 8 in the 1980s then into State 9 in the 1990s, the medium and small shallow lakes typical of Honghu Lake evolve from State 1 in the 1960s into State 2 after the 1980s and the small city (suburban) lakes typical of Donghu Lake evolve from State 2 in the 1960s into State 9 after the 1970s. Further, the 1980s is the key con- version period of the lakes of various types typical of Poyang Lake, Honghu Lake and Taihu Lake con- verting into mesotrophic state, the 1990s is that of Taihu Lake into eutrophic state and the 1970s is thatof the small city (suburban) lakes typical of Donghu Lake into eutrophic state. The series of nutrient evolvement of different typical lakes are similar, but the processes are not synchronous, which is related to the various human and natural driving mechanisms in lake basins.

关键词：长江湖泊富营养化概念模型转变时期驱动机制

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Direct CP violation in hadronic B decays

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science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2 & Lü Caidian3.1. department of Physics, Lishui University, Lishui 3.3.00,china 2. department of Physics, Shanghai Jiaotong University, Shanghai 20003., china 3. Institute of High Energy Physics, Beijing 100049,china su.edu department of Physics Lishui University Lishui 323000 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

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