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Highly efficient use of limited water in wheat production of semiarid area

Progress in Natural Science:Materials International 2003年第12期 1-8页

作者： DENG Xiping 1*, SHAN Lun 2. INANAGA Shinobu 3.and Mohanmed Elfatih K.ALI 4.1. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, institute of Soil and Water Conservation, Chinese Academy of Sciences, Shaanxi 712.00, China 2. Northwest Sci Tech University of Agriculture and Forestry, Shaanxi 712.00, China 3. Arid Land Research Center, Tottori University, Hamasaka 13.0, Tottori 680, Japan 4. El Obeid Research Station, Agricultural Research Corporation, P.O. Box 4.0}, El Obeid, Sudan) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Chinese Academy of Sciences Shaanxi 712100 China Northwest Sci-Tech University of Agriculture and Forestry Shaanxi 712100 China Arid Land Research Center Tottori University Hamasaka 1390 Tottori 680 Japan El-Obeid Research Station Agricultural Research Corporation P.O. Box 429 El-Obeid Sudan

To obtain a greater yield per unit rainfall is one of the most important challenges in dryland wheat production. Highly efficient use of limited water may be one means of achieving this goal. This paper reviewed wheat physiological adaptation and benefits associated with water deficit and variable conditions. In addition, it reveals the compensatory effect of limited irrigation and fertilizer supplement on wheat water use efficiency (WUE) and highlights the breeding of new varieties for high WUE that could improve wheat productivity under water limited environments in the semiarid area. Considerable potential for further improvement in wheat productivity in semiarid area seems to depend on effective conservation of moisture and efficient use of this limited water. Different crops, soil and water management strategies should be adjusted according to the conditions that prevail in the various semiarid areas. By combining soil and water conservation approaches with regulating the cropping system by cultivating drought tolerant and water saving cultivars, the increase in wheat productivity could be achieved.

关键词： semiarid area dryland wheat physiological adaptation WUE improvement.

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Paleoenvironments indicated by the fossil mammalian assemblages from red clay-loess sequence in the Chinese Loess Plateau since 8.0 Ma B.P.

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Science China Earth Sciences 2006年第5期49卷 518-530页

作者： XUE Xiangxu1,2. ZHANG Yunxiang1,2.& YUE Leping1,2.1. State Key Laboratory of Continent Dynamics (Northwest University), {3. of Cenozoic Geology and Environment, De- partment of Geology, Northwest University, Xi’an 710069, China 2. {3. of Earth Environment, State Key Laboratory of Loess and Quaternary Geology, Chinese Academy of Sciences, Xi’an 710075, China 1. State Key Laboratory of Continent Dynamics (Northwest University) Institute of Cenozoic Geology and Environment Department of Geology Northwest University Xi’an 710069 China 2. institute of Earth Environment State Key Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an 710075 China

Information from eleven profiles of eolian earthy red silty clay and loess of the middle of the Late Miocene to Holocene age have been studied and correlated. A complete summary profile with projected isotopic ages and fossil-bearing beds has been assembled. The profile is subdivided into 12.stratigraphic units proceeding from the lower (older) to the upper (younger) one. The character of mammalian assemblages contained in each unit was analyzed and the corresponding pa- leo-climatic environments were deduced. The environmental character of each period and the change from the middle of the Late Miocene at about 8.0 Ma B.P. up to the Holocene progressed from the hot semiarid and semi-moist, warmer-moist, warm-moister of the Late Miocene. To slightly less warm moist, cool-dry, slight-warmer-moister of the Pliocene; later the cool to cold dry periods alternated frequently with the mild semiarid and semi-moist periods of the Quaternary. Vegetation progressed from the grasslands with sparse woods, wooded shrub-grasslands and subtropical forest-grasslands of the Late Miocene age to sparse grasslands and dry grasslands of the Pliocene; and to sparse grasslands, dry grasslands and tundras of the Quaternary. The climate changes in the Neogene were of low-amplitute in a generally warm-humid background. Those of the Quaternary were of higher am- plitude with a longer phase. Cool or cold dry and slightly warm semiarid and semi-moist climates al- ternated on a generally cool-dry background. The tendency since the start of the Quaternary was the change to more northern and western shift in the Loess Plateau, with progressively cooler and dryer conditions. The dramatic uplift of the Qinghai-Xizang (Tibet) Plateau and the forming and expansion of the Arctic ice sheet might be the main reasons of the more pronounced changes in the Quaternary.

关键词： paleoenvironment, mammalian fossils, eolian red clay-loess sequence, Loess Plateau.

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Types, Metallogenic environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in China

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 79-92页

作者： Wang Zhitian and Qin Kezhang Beijing institute of Geology for Mineral resources, CNNC, Beijing Zhang Zhongmin CNNC BEIJING INST GEOL MINERAL RESOURCESBEIJINGPEOPLES R CHINA

Based upon a comprehensive study of 12. copper deposits in China. this paper reaches the following conclusions: 1. The crust in China was solidified pretty late; with the accretion of the plate, the copper mineralization moved towards its margin in space and became successively younger in age. 2. The major copper ore types ever found in the world have mostly been discovered in China, in which the porphyry type seems to be the most important and the massive sulfide type in the transitional bed between marine clastic and carbonate rocks is clearly defined. 3. Carbonate strata are widespread in China and their deposition lasted for a long geological period, so the proportion of copper deposits occurring in them is large as compared with other parts of the world. 4. Seven metallogenic epochs can be recognized, in which the Mesozoic one plays the leading role and the middle(late) Palaeozoic and Cenozoic ones are next in importance. Mineralization was comparatively simple in the early geological period. and became diversified later on. In the early epochs copper deposits related to basaltic magmatism and metamorphosed marine sediments predominated, whereas in the later epochs those related to granitic magmatism and continental sedimentation were dominant. 5. There exist in China thirteen metallogenic provinces, of which the Lower Yangtze downwarping belt, Sanjiang fold system, Jiangnan axis and Xikang-Yunnan axis are of greater significance. 6. The crustal mobility in China was rather pronounced, the polycyclic evolution of the crust has resulted in such obvious phenomena as the inheritance of mineralization, the coexistence of various types and the superposition of different genetic types.

关键词： Metallogenic environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in China Types

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DYNAMIC ANALYSIS OF PARTICLE FLYING VELOCITY IN HIGH VELOCITY OXYGEN FUEL SPRAY

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Chinese Journal of Mechanical Engineering 2000年第4期13卷 273-277页

作者： Wang Zhiping Dong Zujue Huo Shubin (Harbin Research institute of WeldingWenJinlin Shenyang polytechnic University) 哈尔滨焊接所黑龙江沈阳工业大学辽宁沈阳

Based on gas dynamics, thermodynamics, fluid dynamics of multiphase systems and other theories, the dynamic analyses of the particle flying velocity in a high velocity oxygen fuel spray (HVOF) is accomplished. The relationships between the flying velocity of a particle and the flying time or flying length, particle size, hot gas velocity, and pressure or density of the gas are proposed. Meanwhile, the influences of the velocity and mass rate of flow of the flame gas of a HVOF gun, and particle size on the particle flying velocity are discussed in detail. The dynamic pressure concept is introduced to express the flow capacity of hot gas of a HVOF gun, and the relationship between the dynamic pressure of a HVOF gun and the velocity of a particle for depositing is presented.

关键词： Spray Particle Velocity HVOF

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Detection of the urban heat island in Beijing using HJ-1B satellite imagery

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Science China Earth Sciences 2010年第S1期53卷 67-73页

作者： YANG Jun1,GONG Peng2.ZHOU JinXing3.HUANG HuaBing2.& WANG Lei2.1 Key Laboratory of Silviculture and Conservation,Ministry of Education,Beijing Forestry University,Beijing 100083.China 2.State Key Laboratory of Remote Sensing Science,jointly sponsored by the {4. of Remote Sensing Applications,Chinese Academy of Sciences and Beijing Normal University,Beijing 100101,China 3.{4. of Desertification Studies,Chinese Academy of Forestry,Beijing 100091 China 1. Key Laboratory of Silviculture and Conservation Ministry of Education Beijing Forestry University Beijing 100083 China2. State Key Laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China3. Institute of Desertification Studies Chinese Academy of Forestry Beijing 100091 China

Satellite images are used extensively in studying the urban heat island(UHI) *** evaluated the suitability of thermal infrared(TIR) data from the HJ-1B satellite for detecting UHI using a case study in *** modified algorithms for retrieving the land surface temperature(LST) from HJ-1B data were *** results were compared with LST images derived from a Landsat TM thermal band and the MODIS LST *** spatial pattern of UHI generated using HJ-1B data matched well with that produced using TM and MODIS *** the two algorithms,the mono-window algorithm performed better but further tests are *** more frequent coverage than TM and higher spatial resolution than MODIS,the HJ-1B TIR data present a unique opportunity to study thermal environments in cities in China and neighboring countries.

关键词： surface temperature NDVI mono-window algorithm single-channel algorithm

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2.04.全科学与技术国际会议

作者： NIU Guoqing1 2.XU Zhisheng1 & JING Guoxun2.(1 Disaster Prevention Science and Safety Technology institute Central South University Changsha {3.0075 Hunan China) (2.Department of Resource and Material Engineering {{3. {2. University jiaozuo {3.{3.00 {{3. China)

Coal mine is a system with accidents occurring frequently and complicate influential factors. Grey interrelated analysis is applied to analyze the six kinds of factors that affect the situation of pro

关键词： Grey interrelated analysis production system safety system advantage analysis

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南海东部海域表层沉积物类型的研究

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海洋学报 2004年第5期26卷 94-105页

作者：张富元章伟艳张德玉辛春英孟翊陈荣华国家海洋局海底科学重点实验室国家海洋局第一海洋研究所山东青岛266061 华东师范大学

南海东部海域表层沉积物可被分为11种类型:含岩块砾石黏土质粉砂、贝壳珊瑚砂、黏土质粉砂、钙质黏土、钙质软泥、有孔虫砂、深海黏土、含铁锰微粒粉砂质黏土、硅质黏土、含火山灰硅质黏土、含火山灰粉砂质黏土.这些类型按物源和成因可... 详细信息

南海东部海域表层沉积物可被分为11种类型:含岩块砾石黏土质粉砂、贝壳珊瑚砂、黏土质粉砂、钙质黏土、钙质软泥、有孔虫砂、深海黏土、含铁锰微粒粉砂质黏土、硅质黏土、含火山灰硅质黏土、含火山灰粉砂质黏土.这些类型按物源和成因可被分为陆源碎屑、钙质碎屑和硅质碎屑、火山碎屑3.类型,其中陆源碎屑分布面积约占50%,钙质碎屑占2.%,硅质碎屑和火山碎屑各占15%.在物质来源、海底地形、火山作用、生物作用、水动力条件等因素影响和控制下,由于沉积环境的差异,故区内褐色类沉积物最多(60 68%),灰色类沉积物次之(3. 2.%),黄色类沉积物最少(1 12.).台湾省以南到17°N以北海区沉积物以陆源沉积物分布为主;巴士海峡以西海区沉积物较粗,常含砂岩块和砾石;东沙群岛以东海区钙质生物碎屑沉积丰富;中、西部海区以含铁锰微粒沉积物为主;中、南部海区水深大,主要分布硅质沉积物;南部海区、礼乐滩北缘沉积物受礼乐滩珊瑚碎屑影响大,沉积物类型为钙质软泥.

关键词：南海东部表层沉积物沉积物类型沉积环境沉积作用

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Analysis on the Status and Problems of the Tourism Industry in henan Province

Analysis on the Status and Problems of the Tourism Industry ...

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第十五届工业工程与工程管理国际会议

作者： Wang Liping School of Economics and Management henan polytechnic University {2. P.R.China {3.{3.00

＜正＞Tourism industry is a highly market-based upgrading *** the gradual establishment and improvement of socialist market economic system,it has become the most powerful,the most potential economic growth point and growth *** the development of tourism industry in henan Province in recent 10 years,it has made great progress. This paper analyzes the situation and existing problems of henan tourism industry and puts forward some suggestions, which lays the foundation for further studies.

关键词： henan Problems Sustainable Development Tourism Industry

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Prediction of extreme wind speeds in Hong Kong using refined typhoon wind field model

Prediction of extreme wind speeds in Hong Kong using refined...

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第十四届全国结构风工程学术会议

作者： Wen-Feng Huang~1 You-Lin Xu~2.Chi-Wai Li~3.Hong-Jun Liu~4.(1,4.Harbin {3. of Technology Shenzhen Graduate School,Shenzhen 518055) (2.3.The Hong Kong polytechnic University,Hong Kong)

＜正＞A refined typhoon wind field model considering variation of atmospheric pressure with height has been recently proposed by the *** paper aims to use this model together with the Monte Carlo simulation and the typhoon wind decay model for predicting extreme wind speeds in Hong Kong based on 60-year typhoon wind field data recorded by the Hong Kong *** directional and non-directional extreme wind speeds of 50-year return period predicted by the proposed model for the Waglan Island of Hong Kong are compared with the statistical ones directly from the field wind data recorded by the anemometers installed on the *** results show that the proposed model could predict design wind speeds for Hong Kong satisfactorily.

关键词： Extreme wind speed refined typhoon wind field model Monte Carlo simulation typhoon wind data comparison

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Early tectonic uplift of the northern Tibetan Plateau

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Science Bulletin 2005年第15期 108-118页

作者： DAI Shuang1, FANG Xiaomin2.1, SONG Chunhui1, GAO Junping1, GAO Donglin3.& LI Jijun1 1. Key Laboratory of Western China’s Environmental Systems, Ministry of Education of China, and College of resources and Environment, Lanzhou University, Lanzhou 73.000, China 2. {3. of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 3. Qinghai {3. of Salt lakes, Chinese Academy of Sciences, Xining 810008, China

The Hexi Corridor is the northmost foreland basin of the Tibetan Plateau and its formation is controlled by the northern marginal fault of Tibet, Altyn Tagh Fault （ATF）-North Qilian Shan marginal Fault （NQF）, and the southern Kuantan Shan-Longshou Shan Fault （KLF）. So its study is important to understanding the mechanism of Tibet formation and its influence on global climate change. The oldest Cenozoic sediments in the Corridor is the Huoshaogou Formation which consists of terrigenous fine conglomerate, sandstone, sandy mudstone and mudstone, depositing in al-luvial to lacustrine and fan delta sedimentary environments. Detailed paleomagnetic measurements of this sequence at Yumen clearly reveal eleven pairs of normal and reversed polarities. Fossil mammals found around the section support that most of the observed polarities can be well correlated with chrons between 13. and 18r of the standard geomag-netic polarity time scale, yielding ages of 4..2.3..3. Ma. The mean declinations of this sequence and its immediately above stratigraphy indicate an 18.3. rapid clockwise rotation of the Hexi Corridor. Since this sequence has been strongly folded and is capped by an angular unconformity, we think that the presence of the thick alluvial fan conglomeration at the bottom of the foreland basin may indicate the initial de-formation and uplift of the northern Qilian Shan. This proc-ess could occur at latest at 4..2.Ma, driven by the faults NQF and KLF that thrust onto the Hexi corridor respectively from its southern and northern margins. These faults are in an early response to the collision of India with Asia, while the unconformable termination and rotation of the Huoshaogou Formation at3..3. Ma indicate other early episode of rapid tectonic deformation and uplift of the northern Tibet.

关键词： Hexi Corridor Huoshaogou Formation Cenozoic mag-netostratigraphy Tibet uplift.

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