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Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 5. Years

Wuhan university Journal of Natural sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2,3 , ZHOU Wancun 1 ,ZHOU Jieming 4., ZHU Mingcang 3,5.1. Institute of Mountain Hazards and environment, Chinese Academy of sciences , chengdu 61004.,{5.,{4. 2. Graduate university of Chinese Academy of sciences, Beijing 10004.,{4. 3.{5. Institute of Land Resource Management, chengdu 61004.,{5. ,{4. 4. department of Resources and environment science, sichuan normal university , chengdu 610061,{5.,{4. 5. College of Information Engineering, chengdu university of Technology, chengdu 61005.,{5.,{4. Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu Sichuan China Graduate university of Chinese Academy of sciences Beijing China sichuan Institute of Land Resource Management Chengdu Sichuan China department of Resources and environment science Sichuan Normal University Chengdu Sichuan China College of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995.the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 5. years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2, 3 ,HUANG Zhiqin 2, 3, 4.1. The Faculty of Geography and Resources science, sichuan normal university, {4. 610066, sichuan, china 2. Institute of Mountain Hazards and environment, Chinese Academy of sciences, {4. 61004., sichuan, china 3. Graduate university of the Chinese Academy of sciences, Beijing 10004., china 4. Information Center of Land and Resources department of sichuan Province, {4. 61004., sichuan, china The Faculty of Geography Resources science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of sciences 100049 Beijing China Information Center of Land Resources department of sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992 is extracted from the dynamic polygons of 2002. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35.. The areas of steep land cultivated had been slowly reduced from 1992 to 2002. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2, SUN Weiguo1, HOU Shilin3 & FENG Hao4.1. Institute of Physics, College of Chemical Engineering, sichuan university, chengdu 610065. china 2. Institute of Theoretical Physics, Xihua {4. university, Nanchong 637002, china 3. department of Physics, china Oceanography university, Qingdao 266003, china 4. College of Physics, sichuan university, chengdu 610065. china 1. Institute of Physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical Physics Xihua Normal University 637002 Nanchong China 3. department of Physics China Oceanography University 266003 Qingdao China 4. College of Physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3, LU Zhiheng4. & LONG Guilu1,5.1. Key Laboratory For Quantum Information and Measurements of MOE, department of Physics, Tsinghua university, Beijing 100084.china 2. department of Materials {4. and Engineering, Beijing normal university, Beijing 100875. china 3. Testing and Analytical Center, Beijing normal university, Beijing 100875.china 4. department of Physics, Beijing normal university, Beijing 100875. china 5. Key Laboratory For atomic and Molecular Nano{4.s, Tsinghua university, Beijing 100084.china 1. Key Laboratory For Quantum Information and Measurements of MOE Department of Physics Tsinghua University 100084 Beijing China 2. department of Materials science and Engineering Beijing Normal University 100875 Beijing China 3. Testing and Analytical Center Beijing Normal University 100875 Beijing China 4. department of Physics Beijing Normal University 100875 Beijing China 5. Key Laboratory For Atomic and Molecular Nanosciences Tsinghua University 100084 Beijing China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

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Shape Memory Effect of As-aged Fe-14.n-5.i-8Cr-4.i-0.2C Alloy

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Journal of Materials science & Technology 2000年第4期16卷 424-426页

作者： Yuhua WEN, Ning LI and Mingjing TU (department of Materials Shaping and Controlling Engineering, sichuan university, chengdu 610065.{4.) department of Materials Shaping and Controlling Engineering Sichuan University Chengdu 610065 China

The effects of aging temperature on shape memory effect, mechanical properties and microstruc-ture of Fe-14.n-5.i-8Cr-4.i-0.2C shape memory alloy have been studied. The results showed that the second phase particles rich in chromium, manganese and silicon precipitate during aging, and thereby increase the hardness and strength of the alloy. The shape recovery ratio can be remarkably improved by aging and a maximum value can be obtained at 1223 K, which is 68% higher than that of the specimen in solid solution state. When the aging temperature is below 1223 K, the amount of second phase particles increases as the aging temperature increases. The size of austenite grain increases with increasing aging temperature. When the temperature is over 1223 K, the second phase particles can not precipitate. The lack of second phase particles and the increase of grain size make the hardness and shape recovery ratio drastically decrease, when the temperature is over 1223 K.

关键词： Mn Shape Memory Effect of As-aged Fe-14.n-5.i-8Cr-4.i-0.2C Alloy As Fe Cr Ni Si

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Direct in vivo injection of ^(131)I-GMS and its distribution and excretion in rabbit

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World Journal of Gastroenterology 2010年第17期16卷 2120-2128页

作者： Yu Ma,Yi Wan,Li-Geng Duan,Xiao-Li Chen,The Research Unit of Hepato-Bilio-Pancreatology and department of Hepatic Surgery,West china Hospital of sichuan university,{4. 61004.,sichuan Province,china Dong-Hui Luo,Chuan-Qin Xia,College of Chemistry,sichuan university,{4. 61004.,sichuan Province,china Lin Li,department of Nuclear Medicine and The National Key Discipline of Medical Imaging and Nuclear Medicine,West china Hospital of sichuan university,{4. 61004.,sichuan Province,china The Research Unit of Hepato-Bilio-Pancreatology and department of Hepatic Surgery West China Hospital of Sichuan University Chengdu 610041 Sichuan Province China. zean_z@***

AIM: To explore the distribution and metabolism of 131 I-gelatin microspheres ( 131 I-GMSs) in rabbits after direct injection into rabbits’ ***: Twenty-eight healthy New Zealand rabbits were divided into seven groups,with four rabbits per *** rabbit’s hepatic lobes were directly injected with 4..336 ± 5.106 MBq 131 *** day after 131 I-GMSs administration,4.rabbits were randomly selected,and 25. μL of serum was collected for γ *** and thyroid functions were tested on days 1,4.8,16,24.32,4. and 64.after 131 I-GMSs ***-photon emission computed tomography (SPECT) was taken for each group on days 0,1,4.8,16,24.32,4.,64.after 131 I-GMSs administration.A group of rabbits were sacrificed respectively on days 1,4.16,24.32,4.,64.after 131 I-GMSs *** livers were taken out for histological ***: After 131 I-GMSs administration,the nuclide was collected in the hepatic area with *** radiation could be detected on day 4. after 131 IGMSs administration,and radiography could be seen in thyroid areas in SPECT on days 4.8,16 and *** day after 131 I-GMSs administration,the liver function was damaged but recovered 4.d *** days after 131 I-GMSs administration,the levels of free triiodothyronine and free thyroxin were reduced,which restored to normal levels on day *** examination showed that the microspheres were degraded to different degrees at 24.32 and 4. d after 131 I-GMSs *** surrounding parts of injection points were in fibrous *** microspheres were detected in histological examination on day 64.after 131 I-GMSs ***: Direct in vivo injection of 131 I-GMSs is safe in *** may be a promising method for treatment of malignant tumors.

关键词： 131 I Label Gelatin microspheres Animal Rabbit Hepatic Direct injection

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Factors Affecting Transformation Temperatures in Fe-Mn-Si-Cr-Ni Shape Memory Alloy

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Journal of Materials science & Technology 2000年第5期16卷 537-539页

作者： Yuhua WEN+, ding LI and Mingjing TU (department of Materials Shaping and Controlling Engineering, sichuan university, chengdu 610065.{4.) department of Materials Shaping and Controlling Engineering Sichuan University Chengdu 610065 China

The effects of prestrain and annealing temperature on phase transformation temperatures in Fel4.n5.i8Cr4.i shape memory alloy have been studied. The results showed that when the annealing temperature was 673 K, both the At and the Ms temperatures increased appreciably as the prestrain increased, the As temperature increased slightly with increasing prestrain; the resistivity difference at 303 K between the heating and cooling curve also increased with increasing prestrain, which agreed with the recovery strain. The shape memory effect in Fe-Mn-Si-Cr-Ni shape memory alloy is caused by the stress-induced γ→ε martensite transformation and its reverse transformation. When the prestrain was 10%, the Ms temperature decreased remarkably as the annealing temperature increased.

关键词： Factors Affecting Transformation Temperatures in Fe-Mn-Si-Cr-Ni Shape Memory Alloy Fe Mn Cr Ni Si

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Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 137Cs technique

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Chinese science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of environmental Change and Natural Disaster, the Ministry of Education of china, Beijing normal university, Beijing 100875. china 2. Institute of Desert Research, Chinese Academy of {5.s, Lanzhou 730000, china 3. Institute of Mountain Hazards and environment, Chinese Academy of {5.s, chengdu 61004., china 4. department of Physics, sichuan Union university, chengdu 61004., china Key Laboratory of environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu China department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-137 (137Cs) associated with the nuclear weapon tests during the 195.s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 and 2 376.04.Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 137Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 4. years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3) experienced the alternation of erosion and deposition,while the grasslands (S4. S6 and S7) and dry farmlands (S5. suffered erosion only. By using 137Csmodel, the average wind erosion rates for shrub coppice

关键词： 137Cs technique Qinghai-Tibetan Plateau wind erosion.

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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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science china Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2, JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5.& LI Zhen6 1. SKLLQG, Institute of Earth environment, Chinese Academy of sciences, Xi’an 710075. china 2. department of Urban and Resources sciences, Nanjing university, Nanjing 210093, china 3. department of Earth sciences, Nanjing university, Nanjing 210093, china 4. department of Geography, Shaanxi normal university, Xi’an 710062, china 5. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china 6 department of Geography, Qinghai normal university, Xining 810008, china 7. Graduate School of the Chinese Academy of sciences, Beijing 100039, china 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese Academy of sciences Beijing 100039 China 2. department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. department of Earth sciences Nanjing University Nanjing 210093 China 4. department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 25.visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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GIS-based risk analysis of debris flow:an application in sichuan, southwest china

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International Journal of Sediment Research 2008年第2期23卷 138-148页

作者： B.F.DI1,2,3,N.S.CHEN1,P.CUI1,Z.L.LI1,Y.P.HE4.and Y.C.GAO1 3 1 Ph.D.,chengdu Institute of Mountain Hazards and environment,CAS,chengdu 61004.,{5.,{4. of Architecture & environment,sichuan university,chengdu 610065.{5.,Graduate university of Chinese Academy of sciences,Beijing 10004.,{5.,2 Prof.,{4. of Architecture & environment,sichuan university,chengdu 610065.{5.,3 Graduate university of Chinese Academy of sciences,Beijing 10004.,{5. 4.{4. of Civil and environmental Engineering,San Diego State university,5.00 Campanile Dr.San Diego,CA 92121,USA [a]Ph.D. chengdu Institute of Mountain Hazards and environment CAS chengdu 61004. china department of Architecture & environment sichuan university chengdu 610065 china Graduate university of Chinese Academy of sciences Beijing 10004. china [b]Prof. department of Architecture & environment sichuan university chengdu 610065 china [c]Graduate university of Chinese Academy of sciences Beijing 10004. china [d]department of Civil and environmental Engineering San Diego State university 5.00 Campanile Dr. San Diego CA 92121 USA

Debris flow is a serious geologic hazard in *** is estimated that nationally debris flows cause up to 2 billion RMB(25. million US$) in damages and 300-600 deaths and injuries *** mitigate debris flow hazards,it is necessary to map,model,and identify zones of debris flow hazards and vulnerability as to inform the local people about the potential risk with a geographic information *** research presents a regional scale case study modeling debris flow risk(hazard and vulnerability) in sichuan Province,Southwestern *** this area,3,290 debris flows have been identified and the spatial-temporal distribution and activity characteristics of them have been *** on the available meteorological data,a Digital Elevation Model with the rate of 1:25.,000 and a regional geological map,the 24.hr rainfall threshold(y) for debris flow occurrence is closely related(significant at 99% confidence level) to the index(x) defined using a geology factor(rock hardness:a) and a topographical factor(channel gradient:d) where y = 21 + 10200 / x,in which x = 2.7 × ea + 1000 × *** discipline is constructive in developing the rainfall threshold for debris flow activity in remote mountainous areas that lack *** a given watershed,a four-level debris flow hazard map is developed by comparing the rainfall threshold to the design rainfall intensities with 5.-,20-,and 5.year average recurrence intervals,*** degree of debris flow vulnerability is determined by the watershed socio-economic conditions.A four-class debris flow risk map,at the final phase of the research,is generated by combining debris flow hazards and *** the debris flow risk assessment,the sichuan Province is classified into the slight,moderate,severe and very severe regions,which accounts for 36%,19%,20% and 25. of total area respectively.

关键词： Debris flow Geographic information system Hazard Vulnerability Risk Rainfall threshold

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