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research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

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Science china(Technological sciences) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1,CAO Wei 1,WANG HongMei 1,SUN ShuangKe 2 &CHEN QiuWen 3.1 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,china 2 china institute of Water Resources and Hydropower {3.,Beijing 10003.,china 3.{3. Center for Eco-Environmental sciences,chinese academy of sciences,Beijing 100085,china 1. Ertan Hydropower Development Company Ltd. Chengdu 610051 China2. China Institute of Water Resources and Hydropower Research Beijing 100038 China3. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 3.5 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

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植被(植物群落)稳定性研究评述

生态学杂志 2003年第4期22卷 42-48页

作者：张继义赵哈林中国科学院寒区旱区环境与工程研究所兰州730000

稳定性是植物群落结构与功能的一个综合特征。本文对影响植被稳定性的主要干扰因素、群落多样性 (复杂性 )与稳定性的关系、植被稳定性的判定与测度指标、稳定性的机制等方面的研究进展进行了阐述。指出应加强干扰对植被稳定性影响及提... 详细信息

稳定性是植物群落结构与功能的一个综合特征。本文对影响植被稳定性的主要干扰因素、群落多样性 (复杂性 )与稳定性的关系、植被稳定性的判定与测度指标、稳定性的机制等方面的研究进展进行了阐述。指出应加强干扰对植被稳定性影响及提高干旱区人工植被稳定性的技术措施的的研究 ,以指导自然植被的保护利用和人工植被的建设 ,对植被稳定性机制的认识需要从植物群落内部的生物学生态学过程方面进行深入研究。

关键词：植被稳定性多样性干扰测度指标

A NEW APPROACH TO THE PROBLEM OF GRAIN IMPINGEMENTIN MODELLING RECRYSTALLIZATION TEXTUREDEVELOPMENT

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Acta Metallurgica Sinica(English Letters) 1997年第4期10卷 342-348页

作者： L.Q Chen Z. Yingand Z.D. Liang(institute of Metal research, chinese academy of sciences, Shenyang 110015,{3.)(Department of Materials Science and engineering, Northeastern University, Shenyang 110006,{3.) Inst of Metal research Chinese Acad of Sciences Shenyang China

The recrpstallization texture evolution of an interstitial-free (IF) sheet steel dumngannealing is modellcd by Monte Carlo method. A new approach to the problem ofgraln impingement in modelling the development of recrystallization texture is fullydescri6ed, which is based on detailed site analysis and the introduction of proba6ilityvalue Pij for the tro nsition between dtherently oriented groins. As an illustmtive *** theory of orlented nucleation and two critical sizes of nuclei are selected to modelthe mechanism of recrystallization texture formation. The results simulated for severalrepresentative texture components are in agreement with the known experiments.

关键词： IF steel recrystallization texture modelling Monte Carlo method site analysis

Influence of Degree-Day Factor Variation on the Mass Balance of Glacier No. 1 at the Headwaters of ürümqi River,china

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Journal of Earth Science 2013年第6期24卷 1008-1022页

作者：崔玉环叶柏生王杰刘友存 State Key Laboratory of Cryospheric sciences Cold and Arid Regions Environment and Engineering Research InstituteChinese Academy of Sciences School of Resources and Environmental engineering Anhui University Key Laboratory of Water Resources and Environment Tianjin Normal University

The degree-day factor （DDF） is a key parameter in the degree-day model, and the varia- tions in DDF have the significant effects on the accuracy of glacier mass balance modeling. In this study, Glacier No. 1 at the headwaters of Uriimqi （-~O）~Z~=） River in china was selected, and the estimated DDF by stakes-observed mass balance and meteorological data from 1983.2006 was used to analyze the spatio-temporal variability of DDF and its influencing factors, such as climate condition, surface fea- ture, and topography. Then, the ablations from the 1980s to 2000s were estimated using the degree-day modei, and the ablation change from the 1980s to 2000s was divided into the changes caused by climate change and by the ice-surface feature. The following results were obtained：（1） The annual change in DDF for snow was not obvious, whereas that for ice increased, and the increasing trend on the lower glacier was more significant than that on the upper glacier because of decreased albedo caused by vari- ations in ice-surface feature; （2） The DDF for ice clearly decreased with altitude by approximately 0.046 and 0.043.mm.＇C-l-d-Lm-1 on the east and west branches, respectively, and the DDF of the west branch was obviously larger than that of the east branch in the same altitude belt; （3. the changes in mass balance in the summers from the 1980s to 2000s were -3.1 and -467 mm on the east and west branches, respectively. Among the total changes, the components directly caused by climate change were -193.and -198 mm, whereas those indirectly caused by ice-surface feature change were -198 and -269 mm on the east and west branches, respectively.

关键词： degree-day factor mass balance,Glacier No. 1 climate change.

Instabilities of thermocapillary-buoyancy convection in open rectangular liquid layers

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chinese Physics B 2017年第11期26卷 316-323页

作者：姜欢段俐康琦 Key Laboratory of Microgravity Institute of Mechanics Chinese Academy of Sciences School of engineering sciences University of Chinese Academy of Sciences

This article presents the experimental investigation on instabilities of thermocapillary-buoyancy convection in the transition process in an open rectangular liquid layer subject to a horizontal temperature gradient. In the experimental run,an infrared thermal imaging system was constructed to observe and record the surface wave of the rectangular liquid layer. It was found that there are distinct convection longitudinal rolls in the flow field in the thermocapillary-buoyancy convection transition process. There are different wave characterizations for liquid layers with different thicknesses. For sufficiently thin layers, oblique hydrothermal waves are observed, which was predicted by the linear-stability analysis of Smith ＆ Davis in 1983. For thicker layers, the surface flow is distinct and intensified, which is because the buoyancy convection plays a dominant role and bulk fluid flow from hot wall to cold wall in the free surface of liquid layers. In addition, the spatiotemporal evolution analysis has been carried out to conclude the rule of the temperature field destabilization in the transition process.

关键词： thermocapillary-buoyancy convection instability open rectangular liquid layer spatiotemporal evolution

Experimental investigation on a parabolic trough solar collector for thermal power generation

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Science china(Technological sciences) 2010年第1期53卷 52-56页

作者： LIU QiBin1,WANG YaLong1,2,GAO ZhiChao1,2,SUI Jun1,JIN HongGuang1 & LI HePing3.1 institute of engineering Thermophysics,chinese {3. of sciences,Beijing 100190,china 2 Graduate University of chinese academy of sciences,Beijing 100049,china 3.8} Huadian engineering Co.,Ltd,Beijing 100044,china 1. institute of engineering Thermophysics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. China Huadian Engineering Co. Ltd Beijing 100044 China

Developing solar thermal power technology in an effective manner is a great challenge in *** this paper an experiment platform of a parabolic trough solar collector system(PTCS) was developed for thermal power generation,and the performance of the PTCS was experimentally investigated with synthetic oil as the circulate heat transfer fluid(HTF).The solar collector's efficiency with the variation of the solar flux and the flow rate of the HTF was *** collector efficiency of the PTCS can be in the range of 40%-60%.It was also found that there existed a specified delay for the temperature of the HTF to response to the solar flux,which played a significant role in designing the *** heat loss effect on collector efficiency was also studied,which was about 220 W/m for the receiver with a 180°C temperature difference between the collector temperature and the ambient temperature,amounting to about 10% of the total solar energy incident on the *** encouraging results can provide fundamental data for developing the parabolic trough solar thermal power plant in china.

关键词： solar energy parabolic trough solar collector collector efficiency lag behind heat loss

Agro-ecological engineering in china: a way towards sustainable agriculture

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Journal of Environmental sciences 2000年第4期12卷 422-429页

作者： LIU Guo\|hua, FU Bo\|jie (research Center for Eco Environmental sciences, chinese academy of sciences, Beijing 100085,{3.) research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China

Sustainable development, as a “hot topic”, concerns not only economic development but also environmental protection. Agriculture, the base of other economic activities, has faced many difficulties that include over growth population, land decrease, and land degradation and so on. Therefore, how to increase the food supply, to meet the over\|growth population demands, is the main task all over the world at present, especially in the developing countries, such as china, but we also must protect agricultural environment for medium\| and long\|term development simultaneously. Hence, sustainable development in agriculture is the most important estate that we must concern. Its sustainable development determines the sustainability of other economic development to a great extent. Despite chinese government has paid much attention to develop agricultural production and obtained great successions, there are also many shortcomings in chinese agriculture. Therefore, china must seek new approaches for its development and environmental protection that suit local conditions and are based on local resources. Agro ecological engineering, the application of ecological engineering in agriculture, is very thriving in china in recent decades. In this paper, the ecological, economic and social benefits of agro\|ecological engineering are analyzed. The principles are discussed. The results indicated that agro\|ecological engineering can meet the farmer′s short\|, medium\| and long\|term benefits. In the meanwhile, it also concerns not only economic benefits but ecological and social benefits. Therefore, agro\|ecological engineering is a way that leads to sustainable agriculture in the future in china.

关键词： agro-ecological engineering sustainable agriculture sustainable development china

Laboratory test on the combined cooling effect of L-shaped thermosyphons and thermal insulation on high-grade roadway construction in permafrost regions

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research in cold and arid {3. 2009年第4期1卷 307-315页

作者： YuanHong Dong,YuanMing Lai,MingYi Zhang,ShuangYang Li State Key Laboratory of Frozen Soil engineering,cold and arid {3. Environmental and engineering research institute,chinese academy of sciences,lanzhou,Gansu 73.000,china. State Key Laboratory of Frozen Soil engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences cold and arid regions Environmental and {3. research institute Chinese Academy of Sciences

With the completion of the Qinghai-Tibetan Railway,economic development of related areas has been greatly ***,in return,calls for building or upgrading more roadways,especially high-grade *** cold regions,the thawing of permafrost can induce settlement damage of and even failure to railway (or roadway) *** (self-powered refrigera-tion devices that are used to help keep the permafrost cool) have proved effective in mitigating thaw settlement by maintaining the thermal stability of the ***,for high-grade roadway embankments of great width,stabilizing or cooling ef-fects of traditional geotechnological measures may be *** enhance the cooling effect of thermosyphons,an L-shaped thermosyphon was designed.A laboratory test was carried out to study the combined cooling effect of the L-shaped thermosyphon and thermal insulation applying to roadbed *** angle between the evaporator and condenser sections of the L-shaped thermosyphon is 13. degrees,and the L-shaped thermosyphon was inserted into the soil at an angle of 5 degrees with the road *** tested results show that the L-shaped thermosyphon is effective in removing heat from a roadway in *** the ambient air temperature is lower than the soil temperature,the thermosyphon is active and extracts the heat in the soil around *** the ambient air temperature is higher than the soil temperature,the thermosyphon is inactive,and no heat is in-jected into the soil through the L-shaped *** to embankments with straight thermosyphons,the inner parts of the embankments with L-shaped thermosyphons were significantly *** is hoped that the present study would be useful to the application of L-shaped thermosyphons in the construction of high-grade roadways in cold regions.

关键词： L-shaped thermosyphon thermal insulation cooling effect foundation soils high-grade roadway

The Protection Policy of Eco-environment in Desertification Areas of Northern china:Contradictions and Countermeasures

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AMBIO－人类环境杂志 2006年第3期35卷 133-134页

作者： Ma Yonghuan cold and arid regions Environmental and {3. research institute,chinese academy of sciences,260 Dong Gang West Road,lanzhou 73.000,People’s Republic of china.mayonghuan2OOO@sina.com.cnFan Shengyue cold and arid regions Environmental and {3. research institute,chinese academy of sciences,260 Dong Gang West Road,lanzhou 73.000,People’s Republic of china.syfan@***

中国北方沙漠化土地以其广泛的分布和迅速发展构成了区域环境和社会经济发展的丰题。截止2000年，中国北方沙漠化土地面积达3.857×10^5km^2，并且正以每年3.95km^2的速度住扩展。为了遏制不断恶化的生态环境，中国政府曾诉诸丁生物技... 详细信息

中国北方沙漠化土地以其广泛的分布和迅速发展构成了区域环境和社会经济发展的丰题。截止2000年，中国北方沙漠化土地面积达3.857×10^5km^2，并且正以每年3.95km^2的速度住扩展。为了遏制不断恶化的生态环境，中国政府曾诉诸丁生物技术措施和工程措施，但收效甚微。20世纪90年代末，中央政府在陕北看到了退耕还林（草）和封山绿化对保护生态环境的作用，于是节约用水、退耕还林（草）、禁牧以及移民搬迁等生态保护政策便成为中国沙漠化地区生态环境治理的主要内容。但由于生态保护政策与保护生态环境的现实产生了一系列的矛盾，并没有改变牛态环境局部治理、整体恶化的态势。

关键词：保护生态环境环境保护政策沙漠化地区中国北方矛盾退耕还林(草) 20世纪90年代生态环境治理