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Analysis on electrical transport characteristic.of 8-hydroquinoline aluminum film

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Chinese Science Bulletin 1998年第2期43卷 121-124页

作者： Ligong Zhang Dapeng Jiang Xinguang Ren Xueyan Liu Yajun Li Ande Lu Jinshan Yuan Chinese Acad Sci Changchun Inst Phys Changchun 130021 Peoples R China

The current_voltage and capacitance_voltage characteristic.of the organic single_layered electroluminescent diode utilizing 8_hydroquinoline aluminum as active layer have been measured under bias ranging from -5 V to 28 V in this work. A simple model for charge transport process of 8_hydroquinoline aluminum layer is proposed to illuminate the conductivity characteristic.of the diode.

关键词： hydroquinoline aluminum current-voltage characteristic capacitance-voltage characteristic.

characteristic.analysis for a polynomial-like iterative equation

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Chinese Science Bulletin 1998年第3期43卷 192-196页

作者： Janusz Matkowski 1 and ZHANG Weinian 2 1. Department of Mathematics, Technical University, 43_300 Bielsko_Biala, Poland 2. Department of Mathematics, Sichuan Union University, Chengdu 610064, China Department of Mathematics Technical University Bielsko-Biala Poland Department of Mathematics Sichuan Union University Chengdu China

In the light of Euler’s idea for differential equations,a polynomial_like n _order iterative equation is discussed through analyzing its characteristic.polynomial. An unproved result is verified rigorously for the fi... 详细信息

关键词： iterative dynamics functional equation characteristic.

Study on ground temperature change and characteristic.response of engineering geology of permafrost along Qinghai-Tibet Railway

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Science China(Technological Sciences) 2003年第Z1期46卷 78-90页

作者： PAN Weidong, WANG Quancai, YU Shaoshui & ZHANG Xiaoyan Department of Mechanics, School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China Institute of Mountain Hazards and Environment, Chinese Academy of Sciences and Ministry of Water Resources, Chengdu 610041, China State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environment and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China Sichuan Provincial Communications Department, Chengdu 610041, China Lanzhou Univ Dept Mech Sch Phys Sci & Technol Lanzhou 730000 Peoples R China Chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China Chinese Acad Sci State Key Lab Frozen Soil Engn Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China Sichuan Prov Commun Dept Chengdu 610041 Peoples R China

Along with the global warming in the recent scores of years, comparatively big changes have taken place in the weather and other environmental conditions of the permafrost area in the Qinghai-Tibet Plateau, and very big changes have also occurred in the engineering geological conditions of the permafrost area. Based on a large volume of field survey data, this paper discusses the regularities of horizontal and vertical distribution of permafrost, with its focus of analysis on the temperature change characteristic. of the soil in different frozen-soil zones, as well as presents simulation analysis and research for the engineering geologic characteristic.response changes that would occur in the future when the temperature of the frozen soil in different zones rises by 1 and 2.6℃ respectively, which will have a tremendous impact on the stability of constructional work.

关键词： Qinghai-Tibet Railway, permafrost, ground temperature, engineering geological characteristic.

Study on Soil and Water Loss characteristic.of the Railway Construction in Mountain Area

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地球科学进展 2004年第S1期19卷 232-237页

作者： BAI Ming-zhou~1, XU Zhao-yi~1, HUO Yu-hua~1, DONG Yong~2 (1. School of Civil Engineering and Architecture of Beifing JiaoTong University, Beijing 100044,China 2. Personnel Division of the First Railway Survey & Design Institute, Lanzhou 730000, China)

The factor of human project activity is often the immediate cause resulting in soil and water loss. The Baoji-Lanzhou second railway in construction is an example. The soil and water loss law caused by earth and stone mountain railway engineering construction in the northwestern China is studied systematically and that caused possibly by the road bed project, the road moat project, the field project, the tunnel project and the service road project in construction is probed. At the same time, the type, t...

关键词： Mountain railway Soil and water loss characteristic.

Surface texture of quartz grain in booming sand and its acoustic significance

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Chinese Science Bulletin 1995年第20期40卷 1719-1723页

作者：屈建军孙波张伟民王远萍康国定 Institute of Desert Research Chinese Academy of Sciences Lanzhou 730000 China

Booming sand is regarded as a rare and interesting natural phenomenon. Scientists have put forward a variety of inferences and hypotheses on the sound-producing mechanism of booming sand. In recent several decades, scientists have conducted quite a lot of research work on booming sand but little progress has been made in the acoustic mechanism of booming sand due to its complexity. So far, there still exist some divergences of views concerning the influences of surface texture of quartz grain on the sonorous property of booming sand. In this research we have made a systematic analysis on the influence

关键词： booming sand surface texture of quartz grain acoustic characteristic.

Raman spectroscopic characteristic. of microcosmic and photosensitive damage on space structure of liposomes sensitized by hypocrellin and its derivatives

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Science China(Life Sciences) 1998年第5期41卷 459-464页

作者：许以明张志义张伟 Institute of Biophysics Chinese Academy of Sciences Beijing China

Raman spectroscopic characteristic. of microcosmic and photosensitive damage on space structure of DPPC liposomes sensitized by hypocrellin and its derivatives are obvious. The trans conformation decreased and the gauche conformation increased. The longitudinal order_parameter in chains and the lateral order_parameter between chains decreased in different degrees. The lateral packing became loose. Photodamage on the liposomes sensitized by 5 Br hypocrellin B was stronger than that by hypocrellins A and B.

关键词： hypocrellin and its derivatives DPPC liposomes microcosmic and photosensitive damage space structure Raman spectroscopic characteristic.

New Procedure to Derive the Performance Indices Associated with Reservoir Operation Rule

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Journal of Donghua University(English Edition) 2002年第4期19卷 111-114页

作者：王金文张勇传张友权 College of Hydropower and Information Engineering Huazhong University of Science and TechnologyWuhan430074P.R.China School of Electric Power Engineering Kunming University of Science and TechnologyKunming650051P.R.Ching.

Stochastic dynamic programming (SDP) is extensively used in the optimization for long-term reservoir operations. Generally, both of the steady state optimal policy and its associated performance indices (PIs) for multipurpose reservoir are of prime importance. To derive the PIs there are two typical ways: simulation and probability formula. Among the disadvantages, one is that these approaches require the pre-specified operation policy. IHuminated by the convergence of objective function in SDP, a new approach, which has the advantage that its use can be concomitant with the solving of SDP, is proposed to determine the desired PIs. In the case study, its efficiency is also practically tested.

关键词： Dynamic conv ergence, performance index,stochastic dynamic programming, reservoir operation,Markovian characteristic.

Phylogeny reconstruction based on protein phylogenetic profiles of organisms

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Progress in Natural Science:Materials International 2003年第2期 31-35页

作者： CHENG Miao, RUAN Ge and RAO Zihe(Laboratory of Structural Biology & MOE Laboratory of Protein Sciences, Tsinghua University, Beijing 100084, China) Laboratory of Structural Biology & MOE Laboratory of Protein Sciences Tsinghua University Beijing 100084 China

Abstract With the coming of the Post Genomic Era, more and more genomes have been sequenced and it has become possible tostudy phylogeny reconstruction at genome level. The concept of protein phylogenetic profiles of organisms is defined in this work which isused in phylogeny reconstruction by proteome comparisons. This method is more stable than the prevailing molecular systematics methodsand can be used widely. It will develop very fast with the rapid progress in genome sequencing.

关键词： protein phylogenetic profiles molecular evolution proteome characteristic.