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Impact of land-use change on hydrological processes in the Maying River basin, china

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Science china Earth Sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1.3. ZHANG Yu2, LIU Guimin2 & CHEN Lin3.1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 61.041. china 2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, lanzhou 730000, china 3. Resource and Environment School,{3., lanzhou 730000, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Resource and Environment School Lanzhou University Lanzhou China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China

Since the 1.60s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of china. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest china, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1.65. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1.67, has resulted in a mean annual runoff decrease of 28.1.%, a base flow decline of 3..3.%, a drop in the maximum peak discharge of 3..77%, and mean discharge decreases in spring and autumn of 3..05% and 24.87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73.-81., and that to the influence of base flow reaching 62%-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1.2 and Li Jianping2(1. College of Atmospheric Sciences, lanzhou university,{1., china 2. LASG, Institute of Atmospheric {3., Chinese Academy of Sciences, Beijing 1.0029, china) College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Acad. of Sci. Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1.48—2005. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1.76. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Experimental study on high-voltage solar array sustained arc discharge induced by high charging

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Science china(Technological Sciences) 2007年第2期50卷 213-220页

作者： LI Kai1.2, XIE ErQing1. WANG Li2, LIU YanXia1. YANG Yang1. SUN YanZheng3. CUI XinYu3.& MAI ShengLi2 1.School of Physical Science and Technology, lanzhou university, lanzhou 730000, china 2 {3. Institute of physics, lanzhou 730000, china 3.Tianjin Institute of Power Source, Tianjin 3.03.1. china School of Physical Science and Technology Lanzhou University Lanzhou China lanzhou Institute of {1. Lanzhou China Tianjin Institute of Power Source Tianjin China

It has been reported that sustained arc discharge induced by electrostatic discharge (ESD) could cause permanent damage to high-power and high-voltage solar array of spacecrafts. The paper focuses on ESD simulating experiments on Si and GaAs samples, and induces sustained arc discharge. The physical mechanism of sustained arc discharge is discussed by comparing the charging/discharging phenomena between Si and GaAs samples. The experiments show that sustained arc discharge can produce a permanent short-circuit channel between solar cell strings through which the solar array’s photovoltaic power may flow out sustainedly. The analyses show that sustained arc discharge strongly depends on solar array structure, solar array operating voltage, ESD characteristics and cell materials. Keywords high-voltage solar array - electrostatic discharge - sustained arc discharge - mechanism Supported by the National Laboratory of Vacuum, Cryogenics Technology and physics (Grant No. 51.750{1.504DZ2801., and the National High Technology Development Program of china (Grant No. 2002AA7{1.1.8)

关键词： high-voltage solar array electrostatic discharge sustained arc discharge mechanism

Global analysis theory of climate system and its applications

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Chinese Science Bulletin 2003年第10期48卷 1034-1039页

作者： LI Jianping1.2 & CHOU Jifan2,3.1. LASG, Institute of Atmospheric {1., Chinese Academy of Sciences, Beijing 1.0029, china 2. Department of Atmospheric Sciences, lanzhou university,{3., china 3. Training Center for china Meteorological Administration, Beijing 1.0081. china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric Sciences Lanzhou University Lanzhou 730000 China Training Center for china Meteorological Administration Beijing 100081 China

The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.

关键词：整体分析理论气侯体系应用不定性计算法则气侯科学数字模型

Vertical quantitative and dominant population distribution of the bacteria isolated from the Muztagata ice core

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Science china Earth Sciences 2005年第10期48卷 1728-1739页

作者： XIANG Shurong1. YAO Tandong1. 2, AN Lizhe1. 3. WU Guangjian2, XU Baiqing2, MA Xiaojun 3. LI Zhen1. WANG Junxia1.& YU Wusheng1.1. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, lanzhou 730000, china 2. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 1.0085, china 3. College of Life Science,{3., lanzhou 730000, china Chinese Academy of Sciences lanzhou {1.

Vertical distribution of the main bacteria isolated from the Muztagata ice core (about 22.4 m) was investigated by means of cultivation and 1.S rRNA sequence analysis. The results showed that the amount of culturable bacteria fluctuated with ice core depth, and was more in dirty layer than in clean ice, which suggested the close corresponding relationship between high input of the bacteria deposited by wind and snowflow and dirty layer. Most of the bacteria were psychrophiles and psychrotolerants, including α- and γ-proteobacteria, Cryobacterium psychro-philum, CFB (Cytophaga-Flavobacterium-Bacteroides) group, high-G+C gram-positive bacteria (HGC). Acinetobacter sp. and HGC repeatly occurred in different ice depths, and their quantita-tive distribution was consistent with the change of the total amount of culturable bacteria with depth, which suggested the main bio-indicator; while Flavobacterium, Cryobacterium psychro-philum, and α-proteobacteria, also functioned as a secondary indicator of climatic and environ-mental changes. This study is the first report concerning continuous quantitative variation and pattern of the main culturable bacteria in ice core section.

关键词： Pamirs Plateau, ice core, pattern of bacteria, bio-indicator.

Effect of Oxygen Concentration and Annealing Theatment on the Optical Properties of the Transparent Conductive CdIn_2O_4 Thin Films

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Journal of Materials Science & Technology 1998年第2期14卷 161-166页

作者： Bin WU Changyong CHEN and Shibin ZHANG(physics Dept.,{1., lanzhou 730000,{3.)Wanlu WANG and Kejun LIAO(Applied physics Dept., Chongqing university, Chongqing 400044,{3.) physics Dept. Lanzhou University Lanzhou 730000 China Applied physics Dept. Chongqing University Chongqing 400044 China

Transparent conductive cadmium indium oxide films (CdIn2O4) were prepared by r.f. reactive sputtering from Cd-In alloy targets under an Ar-O2 atmosphere. Electrical conductivity of the order of 1.5Ω-1.m-1.and the optical transmission as high as 94% are easily attained by postdeposition annealing treatment. The effects of oxygen concentration in the reactive gas mixture and post-deposition annealing treatment on the optical transmittance as well as optical parameters, such as refractive index (n), extinction coefficient (k), real part (ε') and imaginary part (ε') of the dielectric constant, were studied in the visible and near-infrared region. The highfrequency dielectric constant ε∞ the plasma frequency ωP, and the conduction band effective mass mc of different samples were also investigated

关键词： Thin Effect of Oxygen Concentration and Annealing Theatment on the Optical Properties of the Transparent Conductive CdIn2O4 Thin Films

Two types of changes in apparent resistivity in earthquake prediction

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Science china Earth Sciences 2011年第1期54卷 145-156页

作者： DU XueBin1.2 1.0} Institute of Seismology,{1. Earthquake Administration, lanzhou 730000,{1. 2lanzhou Base of Earthquake Science Institute,{1. Earthquake Administration, lanzhou 730000,{1. lanzhou Institute of Seismology China Earthquake Administration Lanzhou China lanzhou Base of Earthquake Science Institute China Earthquake Administration Lanzhou China

Two types of changes in apparent resistivity (AR) have been linked to earthquake occurrences. This paper studies the changes and their causes, in detail with the ultimate purpose of developing and assessing a method of earthquake (EQ) prediction. The AR changes of the first type (CFT) are considered to be precursors related to earthquakes (EQs); these appear mostly in the medium-term period before EQs and in the short-term period preceding EQs. The changes of the second type (CST) are characterized by a turning anomaly of a long-trend AR variation or the drastically descending/ascending anomaly superimposed on such a variation; these appear synchronously in large areas, such as the Chinese mainland, and northern and northwestern china, ect. Their spatio-temporal clusters correspond well to high seismicities in the areas and distant great EQs around the Chinese mainland. Based on the behaviors of the two types of changes, the AR changes observed prior to the Ms8.0 Wenchuan EQ of 2008 are studied. The results show that in the medium-term period before the EQ, noticeable anomalies appeared synchronously at four stations around the Songpan-Ganzi active block, but only weak upward changes were observed in the short-term period preceding the EQ, which caused the prediction of the imminent EQ to fail.

关键词： strong earthquake apparent resistivity two types of changes spatio-temporal cluster Wenchuan earthquake

Organic geochemical studies of sinking particulate material in china sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

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Chinese Science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, SONG Jinming, ZHOU Shixin and LUO Binjie1. lanzhou Institute of Geology, Chinese Academy of Sciences,{1., china 2. Earthquake Research Institute of lanzhou, SSB,{1., china 3. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071. china lanzhou Institute of Geology Chinese Academy of Sciences Lanzhou China Earthquake Research Institute of lanzhou SSB Lanzhou China Institute of Oceanology Chinese Academy of Sciences Qingdao China

SINKING particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science china({1.,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1.3.4, JIANG YunGuo1.& LI XinGuo2,3.1.Institute of Theoretical physics, College of Applied Sciences, Beijing university of Technology, Beijing 1.0022, china 2 Institute of {3. physics, Chinese Academy of Sciences, lanzhou 730000, china 3.Center of Theoretical Nuclear physics, National Laboratory of Heavy Ion Collisions, Chinese Academy of Sciences, lanzhou 730000, china 4 china Center of Advanced Science and Technology (World Laboratory), Beijing 1.0080, china Institute of Theoretical physics College of Applied Sciences Beijing University of Technology Beijing China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou China china Center of Advanced Science and Technology (World Laboratory) Beijing China Institute of modern {1. Chinese Academy of Sciences Lanzhou China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity