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Study on the changes of water cycle and its impacts in the source region of the Yellow River

Science china(Technological Sciences) 2004年第z1期47卷 142-151页

作者： ZHANG Shifeng1. JIA Shaofeng1. LIU Changming1. CAO Wenbing2, HAO Fanghua3. LIU Jiuyu4 & YAN Huayun5 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 1.01.1.{1. 2.{1. university of {3., Beijing 1.0083,{1. 3. Beijing Normal university, Beijing 1.0875,{1. 4. Bureau of Hydrology of Yellow River Conservancy Commission, Zhengzhou 450003.{1. 5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province, Xining 81.001.{1. 1. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China2. China University of Geosciences 100083 Beijing China3. Beijing Normal University 100875 Beijing China4. Bureau of Hydrology of Yellow River Conservancy Commission 450003 Zhengzhou China5. Bureau of Hydrology and Water Resource Investigation of Qinghai Province 810001 Xining China

The water cycle in the source region of the Yellow River underwent great changes in the 1.90s. The major features of the changes are as follows: the gauged runoff declined significantly while the precipitation increased slightly, and the runoff process was more concentrated on the flood season. Water balance analyses indicate that the pondage was kept in the status of negative equilibrium, causing eco-environmental problems. The runoff decrement is due to evaporation increment in this region. Studies show that the runoff process in this region is closely related to that of the other hydrological stations in the upper reaches. When the runoff declines in the source regions, the amount of water also declines in the whole upper reaches of the Yellow River, affecting the balance between water demand and supply. Meanwhile changes will take place in the water cycle of the river course system when the eco-environment deteriorates. The trend of water cycle change in the source region is that the runoff will keep declining with the increment of evaporation caused by temperature rise in the northwest of china in the 21.t century. But the hydraulic engineering in the source region will help to mitigate the deterioration of local eco-environment system, though the impacts to the lower reaches of this project may not be the case.

关键词： source region of the Yellow River, water cycle, evaporation, negative equilibrium.

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Subsidence control and farmland conservation by solid backfilling mining technology

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中国有色金属学会会刊：英文版 2011年第S3期21卷 665-669页

作者： GUO Guang-li1. 2, FENG Wen-kai3. ZHA Jian-feng1. 2, 3. LIU Yuan-xu1. 2, WANG Qiang1. 2 1. Key Laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping, china university of Mining and Technology, Xuzhou 221.1., china 2. Jiangsu Key Laboratory of Resources and Environmental Information Engineering, china university of Mining and Technology, Xuzhou 221.1., china 3. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu university of Technology, Chengdu 61.059, china [a] Key Laboratory for Land Environment and Disaster Monitoring of the State Bureau of Surveying and Mapping China University of Mining and Technology Xuzhou 221116 China [b] Jiangsu Key Laboratory of Resources and Environmental Information Engineering China University of Mining and Technology Xuzhou 221116 China [c] State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

Solid backfilling mining technology, which decreases the height of fissure zone and caving zone, and alleviates the subsidence, is a new technology for farmland conservation. Based on the situation analysis of farmland destruction in mining area, three ways for farmland protection were proposed. In order to improve the feasibility of this technology, the limited filling materials should be used to increase resources recovery ratio, and then the surplus materials could be backfilled into goaf. An index, namely farmland conservation ability, was put forward to optimize the ways for farmland conservation. At last, the Wanbei coal mine was taken as a case for farmland conservation. It was shown that 3.40 t dull coal was substituted and 52 hm2 farmland was conserved by solid backfilling mining in this coal mine.

关键词： solid backfilling farmland conservation mining subsidence equivalent mining height

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Size distributions and magic number characteristics of cluster configurations formed during solidification processes of liquid metal Al

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Science china(Technological Sciences) 2006年第2期49卷 172-187页

作者： LIU Rangsu1. LIU Fengxiang1. DONG Kejun1. ZHENG Caixing1. LIU Hairong2, PENG Ping2 & LI Jiyong3.1. Department of Physics, Hunan {1., Changsha 41.082, china 2. Department of Material Science and Engineering, Hunan {1., Changsha 41.082, china 3. Department of Chemistry, Hunan {1., Changsha 41.082, china 1. Department of Physics Hunan University Changsha 410082 China 2. Department of Material Science and Engineering Hunan University Changsha 410082 China 3. Department of Chemistry Hunan University Changsha 410082 China

A molecular dynamics simulation study has been performed for a large systemconsisting of 1.0000 liquid metal Al atoms to investigate the formation and magic numbercharacteristics of the cluster configurations formed during the rapid solidification processes. Thecluster-type index method (CTIM) has been adopted to describe various types of clusterconfigurations. The results indicate that the icosahedral clusters (1. 0 1. 0) and theircombinations play the most important role in the rnicrostructure transitions during solidificationprocesses; for the cluster configurations of different levels formed by various combinations withdiffering numbers of basic clusters, their size distributions possess obvious magic number sequencewhich is in turn as 1.0}1.0}, 1.(21., 26-28(27), 3.-3.(3.), 3.-40, 43.44, 48..., (those in bracket arethe corresponding value in liquid state); the magic numbers correspond to the peak value positionsof the cluster numbers for corresponding level formed with various combinations by 1. 2, 3. 4, 5, 6,7, ...basic clusters, respectively. This magic number sequence is in good agreement with theexperimental results obtained by Harris et al. At the same time, this simulation study also gives ascientific and reasonable explanation to these experimental results.

关键词： liquid metal, solidification processes, cluster configuration, magic numbers, computer simulation.

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Solving the input data in error correc-tion of optical fabrication by finite Fourier coefficient algorithm

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Science china(Technological Sciences) 2006年第1期49卷 50-60页

作者： CHENG Haobo1.2, SUN Guozheng3.& FENG Zhijing2 1. Department of Optical Engineering, Beijing Institute of Technology, Beijing 1.0081.{1. 2. Department of Precision Instruments and Mechanology, Tsinghua university, Beijing 1.0084,{1. 3.{1. North Industries Group Corporation, Beijing 1.0089,{1. 1. Department of Optical Engineering Beijing Institute of Technology Beijing 100081 China 2. Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China 3.{1. North Industries Group Corporation Beijing 100089 China

A free-form lens (FFL) is a special surface that is difficult to be fabricated. FFL are usually fabricated by computer-controlled optical surfacing (CCOS) technique. During CCOS, the material removal amount is determined by the unit removal function (URF) convoluting with the input data――the dwell time. When the removal amount and the URF are known, how to solve the input data involves the special algorithm――deconvolution. Usually, the input data are solved by virtue of low pass filter or iterative methods. However, an approximation solution would destroy the machining stability nec-essary to perform precisely CCOS. In this paper, to solve the input data, a new method that is based on the finite Fourier coefficient is put forward. It can give a continuous and accurate solution for fabricating choice. Several parameters are simulated, which influ-ence the process of CCOS, and evaluating on the effect of the method is also carried out. Experimental results verify that this method is suitable for guiding the manufacturing of high precision FFL.

关键词： optical fabrication, computer controlled optical surfacing, free-form lens, finite Fourier coefficient, error correction.

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Landscape ecological assessment and eco-tourism development in the South Dongting Lake Wetland, china

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Journal of Environmental Sciences 2003年第2期15卷 271-278页

作者： HE Ping 1.2, WANG Bao-zhong 1.3.(1.Central South Forestry {1., Zhuzhou 41.006, china 2.china International Engineering Consulting Corporation, Beijing 1.0044, china 3.Nanjing {1., Nanjing 21.093. china Central South Forestry university Zhuzhou 412006

As an important resource and the living environment of mankind, wetland has become gradually a highlight, strongly concerned and intensively studied by scientists and sociologists. The governments in the world and the whole society have been paying more and more attention on it. The Dongting Lake of china is regarded as an internationally important wetland. For a rational development and protection of the wetland, an investigation and studied on its resources and its value to tourism in the South Dongting Lake was conducted, to create an assessment system of the ecological landscapes, and to evaluate qualitatively and quantitatively the value of wetland landscape to the eco-tourism. The results showed that the scenic value of the South Dongting Lake Wetland satisfied the criterion of AAAA grade of china national scenic attraction. The eco-tourism value of the landscape cultures in the South Dongting Lake Wetland was discussed with emphasis. It were formulated that a principle and frame of sustainable exploitation of the wetland landscapes and it was proposed as well that establishing a Wetland Park and developing eco-tourism in the South Dongting Lake. Wetland is a fragile ecosystem with low resistance to the impact of the exploitation. Thus, we must pay intensively attention to the influence of exploitation on the landscape, take the ecological risk in account to employ a right countermeasure and avoid the negative affection.

关键词： South Dongting Lake wetland landscape eco-tourism Wetland Park ecological assessment

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Cretaceous-Early Eocene Tectonic Stress Field in china

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Acta Geologica Sinica(English Edition) 1989年第3期63卷 227-239页

作者： Wan Tianfeng and Zhu Hong china {1. of geosciences, Beijing, china 2Wan Tianfeng male born in 1938 engaged in geological education since 1959 and now is a professor of the Teaching and Research Group of Structural Geology China University of Geosciences Beijing 100083. china {1. of geosciences Beijing China

The Cretaceous-early Eocene tectonic stress field in china was reconstructed using the data of {1.9 largeand medium-scale flexural folds and 1.7 joint sets. It was found that the maximum compressive principal stress axis in eastern china dips {1.° NE (nearly horizontal), and strikes SW 21.°, whereas that in western china dips 1.° NE (also nearly horizontal) and trends SW 1.5°. The estimation of the dip angles of fold limbs and the palaeotectonic stress values indicates that there was a tendency of gradual weakening of tectonism from southwestern to northeastern china in the Cretaceous-early Eocene. At the depth of 2-{1.km, the differential stress value changes from 1.{1.MPa in Tibet to 1.0 MPa in North and East china.The authors consider that the tectonic stress of this period was related to the north-northeastward movement and push of the Indian-Australian plate.

关键词： Cretaceous-Early Eocene Tectonic Stress Field in china

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Measurement of the linear electro-optic coefficient of a minute cBN sample

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Science china(Technological Sciences) 2005年第2期48卷 233-340页

作者： DOU Qingping1. , MA Haitao1. JIA Gang1. CHEN Zhanguo1.2 & ZHANG Tiechen3.1. College of Electronic Science and Engineering, State Key Laboratory on Integrated Optoelectronics, Jilin {1., Changchun 1.0}023. china 2. Mudanjiang Normal Institute, Mudanjiang 1.701., china 3. State Key Laboratory of Superhard Materials, Jilin {1., Changchun 1.0}01., china 1. College of Electronic Science and Engineering State Key Laboratory on Integrated Optoelectronics Jilin University 130023 Changchun China 2. Mudanjiang Normal Institute 157012 Mudanjiang China 3. State Key Laboratory of Superhard Materials Jilin University 130012 Changchun China

Cubic boron nitride (cBN) is a kind of artificial (synthetic) crystal. Transverse electro-optic modulation in a minute cBN sample was carried out. Basing on the practical form of the crystal, we established the theoretical and experimental method according to the sample. For the first time, the linear electro-optic effect was observed in cBN, and half-wave voltage of the cBN sample was measured successfully. Furthermore, its linear electro-optic coefficient was calculated at 1.1.×1.?1. m/V.

关键词： cBN crystal, linear electro-optic effect, half-wave voltage, linear electro-optic coefficient.

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Hydrocarbon test in lower-layer atmosphere to predict deep-sea petroleum or hydrate in the Okinawa Trough: an example

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Acta Oceanologica Sinica 2003年第4期22卷 569-576页

作者： Gong Jianming1. Chen Jianwen 1. 2, Li Gang1. Zhang Xunhua1. Li Jipeng3. Huang Fulin1.1. Qingdao Institute of Marine Geology, Qingdao 266071.{1.. 2. Ocean university of{1., Qingdao 266003.{1. 3. Hefei Institute of Petroleum Chemical Exploration,{1. Petroleum Exploration and Development Research Institute, Hefei 23.022,china Qingdao Inst Marine Geol Qingdao 266071 Peoples R China Ocean Univ china Qingdao 266003 Peoples R China china Petr Explorat & Dev Res Inst Hefei Inst Petr Chem Explorat Hefei 230022 Peoples R China

Light hydrocarbon (methane, ethane, propane, butane and CO2) test and C isotopic analysis of CO are conducted for over 1.0 lower-layer atmospheric samples from the East china Sea slope and the Okinawa Trough. The results show that the lower-layer atmosphere mainly consists of CO2 and then of CH4, and the CO2 concentrations are calculated to have a high average value of 0.87 omega/1.(-2) about three times that of the regional background (0-{1.omega/1.(-2)). The result also shows that the average value of C isotope - 20.8 x 1.(-{1. is given to the CO2, inferring that it is inorganic gas. Thus, for the future 's work in the Okinawa Trough, special attention should be paid to CO2 hydrate, which is very possibly an important hydrate type.

关键词： lower-layer atmosphere hydrocarbon test C isotopic analysis deep-sea petroleum gas hydrate

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Analytical method of Cr stable isotope and its application to water pollution survey

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Chinese Science Bulletin 2010年第7期55卷 664-669页

作者： GAO YongJuan 1.2,3.MA Teng 4,5,LING WenLi 1.2,LIU CunFu 4,5 & LI Li 4,5 1.aculty of Earth Science,{1. university of geosciences,Wuhan 43.074,{1. 2State Key Laboratory of Geological Processes and Mineral Resources,{1. university of geosciences,Wuhan 43.074,{1. 3.Graduate School,{1. university of geosciences,Wuhan 43.074,{1. 4 Biogeological and Environmental Geology Laboratory of Ministry of Education({1. university of geosciences) ,Wuhan 43.074,{1. 5 Sino-Hungary Joint Laboratory of Environmental Sciences and Health,{1. university of geosciences,Wuhan 43.074,{1. Faculty of Earth Science China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Graduate School China University of Geosciences Wuhan 430074 China Biogeological and Environmental Geology Laboratory of Ministry of Education (china {1. of geosciences) Wuhan 430074 China Sino-Hungary Joint Laboratory of Environmental Sciences and Health China University of Geosciences Wuhan 430074 China

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei Province were analyzed by this *** samples showδ53.r values ranging from-1.7‰to 7.3.and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53.r value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术

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Size fractionated biomass and productivity of phytoplankton and new production in the Prydz Bay and the adjacent Indian sector of the Southern Ocean during the austral summer 1.98/1.99

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Acta Oceanologica Sinica 2003年第4期22卷 651-670页

作者： Cai Yuming 1.3. Ning Xiuren 1.2,3. Zhu Genghai3. Shi Junxian3.1. Key Laborary of Submarine geosciences of State Oceanic Administration,Hangzhou 3.001.,china. 2. Key Laborary of Ocean Dynamic Processes and Satellite Oceanography of State Oceanic Administration,Hangzhou 3.001.,china 3. Second Institute of Oceanography of State Oceanic Administration, Hangzhou 3.001.,china Key Lab Submarine Geosci State Ocean Adm Hangzhou 310012 Peoples R China Key Lab Ocean Dynam Proc Satellite Oceanog State Ocean Adm Hangzhou 310012 Peoples R China Inst Oceanog State Ocean Adm 2 Hangzhou 310012 Peoples R China

The paper deals with the studies on the cell abundance, the composition of dominant species, size fractionated biomass and productivity of phytoplankton, new production, the environmentally restricted mechanism in the Prydz Bay and the adjacent Indian sector of the Southern Ocean during the austral summer 1.98/1.99. The results showed that there was marked feature of spatial zonation in the sea areas investigated. In the Prydz Bay and its adjacent continental shelf, the biomass and productivity of phytoplankton were high; those of continental slope and open ocean area were obviously low. The nutrient concentration had opposite distribution trend, due to the consumption of phytoplankton. It mainly affected by the vertical stability of water column, grazing pressure of zooplankton, temperature and light etc. The results of size-fractionation showed that the average contribution of netplankton to total chlorophyll a in studied sea areas was 52.2 %, those of nano- and picoplankton were 29.4 % and 1..4 %, respectively. The average contribution of netplankton to total primary production was 52.4 %, those of nano- and picoplankton were 28.7 % and 1..9 %, separately. It is same as previous conclusion that the contribution of picoplankton to productivity is slightly larger than that to biomass of phytoplankton communities. The average new production and f-ratio were 23..6 mg/ (m(2.)d) and 0.43. respectively.

关键词： phytoplankton standing stock primary productivity size-fractionation new production the Southern Ocean

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