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Indoor imitation experimental study on driving factors of rainfall-runoff process

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Science china Earth sciences 2005年第3期48卷 417-428页

作者： ZHANG Shifeng1, LIU Changming 1, XIA Jun1, TAN Ge 1, LI Lin1, LIU Caitang1, ZHOU Changqing 1 & GUO Lei2.1. Institute of geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, china 2. college of Water Resources and Hydropower Engineering, Wuhan university, Wuhan 430072. china 1. Institute of geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. college of Water Resources and Hydropower Engineering Wuhan University 430072 Wuhan China

The driving actions of rainfall-runoff process can be attributed to two aspects. The first is the influence of precipitation process, and the second is that of the ground pad. The re- search results of 179 indoor experiments conducted to imitate rainfall-runoff process indicate that both precipitation duration and intensity play important roles in affecting confluence lag time, which is obviously inconsistent with the traditional hypotheses. The nonlinear relationship is of great significance to the confluence curve especially when the precipitation duration is less than the total confluence time or the precipitation intensity is small. Therefore it can be concluded that the unit hydrograph (UH) can be applied to rainfall-runoff process imitation in the humid areas in the south china region. However, the UH application should be strictly modified in accordance with precipitation conditions in the arid and semiarid region of north china where the precipitation duration is short and the intensity is unstable. It will be hard to get ideal imitation results if the UH is applied blindly without considering specific conditions in the north china region. This also explains the unsatisfactory imitation results caused by using various hydrological models in the north china region. When the precipitation duration is short, and the watershed has not reached total watershed concentration, the characteristics of confluence change greatly, which reflects the actual situation in the north china region. Therefore necessary nonlinear corrections should be made when UH is applied. If the duration is longer than the total confluence time and the balance between pondage and discharge is stricken, the imitation research results will be applicable to both rainfall-runoff relation with longer duration in the south china region and the basic theoreti- cal research on runoff generation and concentration. On conditions of adequate rainfall, peak discharge is in linear relationship with inten

关键词： rainfall-runoff, driving factors, indoor imitation, experiment.

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science china Earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3, LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of geographic sciences and Natural Resources Re-search, Chinese Academy of sciences, Beijing 100101, china 2. Institute of Forestry, Chinese Academy of Forestry sciences, Beijing 100091, china 3. Department of Civil Engineering, university of Hong Kong, Hong Kong, china 4. Eco-environmental Research Center, Chinese Academy of sciences, Beijing 100085, china 5. college of Resources and Environment, Southwest Agricultural university, {12. 400716, china Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. college of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 530 mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 30%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

Acyclic Edge Coloring of Planar Graphs without Adjacent Triangles

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Journal of Mathematical Research with Applications 2012年第4期32卷 407-414页

作者： Dezheng XIE 1,,Yanqing WU 1,2.1.college of Mathematics and Statistics,chongqing {2.,chongqing 401331,P.R.china 2.School of Mathematics and Computer Science,Shanxi normal {2.,Shanxi 041000,P.R.china college of Mathematics and Statistics Chongqing University Chongqing 401331

An acyclic edge coloring of a graph G is a proper edge coloring such that there are no bichromatic *** acyclic edge chromatic number of a graph G is the minimum number k such that there exists an acyclic edge coloring using k colors and is denoted by χ' a(G).In this paper we prove that χ ' a(G) ≤(G) + 5 for planar graphs G without adjacent triangles.

关键词： acyclic edge coloring acyclic edge chromatic number planar graph.

Effect of D-allethrin on proteinase activity in the midgut of the spider Pardosa pseudoannulata detected by bulk acoustic wave impedance technique

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Progress in Natural Science:Materials International 2007年第12期17卷 1521-1526页

作者： Wang Zhi1, Fu Xiuqin2. Rao Liqun1 and Lu Xiangyang1(1. college of Bioscience & Biotechnology, Hunan Agriculture university, Changsha 41012.,{2. 2. college of Life Science, Hunan normal university, Changsha 410081,{2.) college of Bioscience & Biotechnology Hunan Agriculture University Changsha 410128 China college of Life Science Hunan Normal University Changsha 410081 China

The piezoelectric bulk acoustic wave (BAW) impedance analysis method was employed to monitor in situ the proteinase-catalyzed hydrolyzation of casein and the effect of pesticide D-allethrin on the proteinase activity in the midgut of the spider Pardosa pseudoannulata, and the results obtained were verified by ultraviolet spectroscopy. The hydrolyzation was significantly increased in the presence of low-dose D-allethrin, whereas significantly inhibited in the presence of high-dose D-allethrin, and a correlation was found precisely between the enzyme activity reflected by the final frequency shift after the hydrolyzation and the concentration of D-allethrin, with a significant frequency response observed even at a 1.5×10-5 volume ratio of D-allethrin to distilled water. The present work may have presented a novel method feasible for study on the mechanism of excitability of spiders under low-dose D-allethrin pesticide and quick detection of proteinase activity.

关键词： Pardosa pseudoannulata D-allethrin proteinase activity ultraviolet spectroscopy piezoelectric bulk acoustic wave impedance method.

On (2.m + 1)-variable symmetric Boolean functions with submaximum algebraic immunity 2.(m-1)

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Science china Mathematics 2009年第1期52卷 17-28页

作者： LIAO QunYing1, LIU Feng2.& FENG KeQin2.1 college of Mathematics and Software sciences, Sichuan {2. university, Chengdu 610066, china 2.Department of Mathematical sciences, Tsinghua university, Beijing 100084, china college of Mathematics and Software sciences Sichuan Normal University Chengdu 610066 China Department of Mathematical sciences Tsinghua University Beijing 100084 China

All (2. +1)-variable symmetric Boolean functions with submaximal algebraic immunity 2.-1 are described and constructed. The total number of such Boolean functions is 32.·2.m-3 +3m-2.· 2. - 2.for m≥2.

关键词： symmetric Boolean function algebraic immunity cryptography

Ibsen’s Ethical Dilemma: A Case Study of Catiline

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外国文学研究 2005年第6期27卷 14-19页

作者： Zhu Weihong college of Literature, Central china {2. university English Department of college of Foreign Languages Central China Normal University China

Catiline, Ibsen’s first play, has often been undervalued. Ibsen’s comments on this play that the ideas he expressed in this juvenile attempt are still what he thinks of after he has made great achievements in dramatic creation exactly show its true value. To a large extent, it is Catiline’s persistent pursuit of his ideal that may have moved the dramatist who has throughout his own life pursued his own ideal. What’s more, Ibsen may also have noticed the similar ethical dilemma that faces him and Catiline: the contraction between his earthly duties and his pursuit of the ideal.

关键词：文学伦理学易卜生戏剧创作挪威

Development pattern of the industry form in mountains area:a case study of the Three Gorges Reservoir area

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Ecological Economy 2008年第1期4卷 74-84页

作者： Feng Quanguang Coollege of economics and management southwest universityChongqing 400716P.R.China School of Economics and management Chongqing normal universityChongqing 400047P.R.China

The mountainous areas （mountain, plateau and hilly area ） cover than 85% of total land territory of *** and humanity in very mountainous ares has its own geographic *** the process of industrialization and urbanization in china, realizing the sustainable development of the mouniainous areas, optimizing man-land system, and adopting and continuously developing corresponding economic modes of the mountainous areas with multi-functions of economy, ecalogy, culture and society to chararacterize production content, mode of production. mode of operation is not only helpful to econonty, society and ecological value and is of great aesthetic value,but also solve the technological problems of the subject of starting undertaking to finally transform the regional resource advantage of the mountainous area into the advantage of capital and technology for economic development and to get rid of the contradiction between underdeveloped economy and abundant resources. This paper takes the Three Gorges Reservoir（TGR） area for example to show that it＇s of great practical and theoretical significance ,regional distribution,variety structure and quality structure.

关键词： Mountainous area Regional mountain economy Mountain economic mode The TGR area

Improvement of sensitivity of graphene photodetector by creating bandgap structure

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Chinese Physics B 2017年第11期26卷 429-433页

作者：张倪侦何孟珂余鹏周大华 chongqing Key Laboratory of Photo-Electric Functional Materials College of Physics and Electronic EngineeringChongqing Normal University chongqing Key Laboratory of Multi-scale Manufacturing Technology Chongqing Institute of Green and Intelligent TechnologyChinese Academy of Sciences

Graphene has aroused large interest in optoelectronic applications because of its broad band absorption and ultrahigh electron mobility. However, the low absorption of 2.3% seriously limits its photoresponsivity and restricts the relevant applications. In this paper, a method to enhance the sensitivity of graphene photodetector is demonstrated by introducing electron trapping centers and creating a bandgap structure in graphene. The carrier lifetime obviously increases, and more carriers are collected by the electrodes. Compared with intrinsic graphene detector, the defective graphene photodetector possesses high photocurrent and low-driving-voltage, which gives rise to great potential applications in photodetector area.

关键词： graphene photodetector photocurrent bandgap

Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions

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Science china Earth sciences 2006年第2期49卷 193-201页

作者： LEI Tingwu1,2. LIU Han1, PAN Yinghua3, ZHAO Jun2. ZHAO Shiwei2.& YANG Yonghui2.1. The Key Laboratory of Modern Precision Agriculture System Integration Research, college of Hydraulic and Civil Engineer-ing, china Agricultural {2., Beijing 100083, china 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Yangling 712.00, china 3. geographic and Resources Management college, Yantai normal {2., Yantai 2.402., china 1. The Key Laboratory of Modern Precision Agriculture System Integration Research College of Hydraulic and Civil Engineering China Agricultural University Beijing 100083 China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Yangling 712100 China 3. geographic and Resources Management college Yantai Normal University Yantai 264025 China

The soil infiltrability of hill-slope is important to such studies andpractices as hydrological process, crop water supply, irrigation practices, and soil erosion. A newmethod for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-outwas advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimatedfrom the advances of runoff on soil surface and the water running out of the slope were *** of 2.cases were conducted. Case Ⅰ was done under a rainfall intensity of 2. mm/h, at aslope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case Ⅱ was under arainfall intensity of 60 mm/h and a slope of 2.° with a runoff/on length (area) ratio of 1 : *** ring method was also used to measure the infiltrability for comparison purposes. Theexperiments were done with soil moisture of 10%. Required data were collected from laboratoryexperiments. The infiltrability curves were computed from the experimental data. The resultsindicate that the method can well conceptually represent the transient infiltrability process, withcapability to simulate the very high initial soil infiltrability. The rationalities of the methodand the models were validated. The errors of the method for the two cases were 1.82./1.39% and4.49%/3.52.% (Experimental/Model) respectively, as estimated by comparing the rainfall amount withthe infiltrated volume, to demonstrate the accuracy of the method. The transient and steadyinfiltrability measured with double ring was much lower than those with this new method, due towater supply limit and soil aggregates breaking down at initial infiltration stage. The method canovercome the short backs of the traditional sprinkler method and double ring method for soilinfil-traility. It can be used to measure the infiltrability of sloped surface underrainfall-runoff-erosion conditions, in the related studies.

关键词： Infiltrability, runoff-on-out, rainfall, sloped surface, model.