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Pedosphere 2006年第3期16卷 319-325页

作者： ZHANG Tong-Hui SU Yong-Zhong CUI Jian-Yuan ZHANG Zhi-Hui CHANG Xue-Xiang cold and arid regions Environmental and {3. research institute Chinese Academy of Sciences Lanzhou 730000 （China）

Caragana microphylla Lam., a pioneer leguminous shrub species for vegetation re-establishment, is widely distributed in the semi-fixed and fixed sandy lands of the Horqin region. Some soil chemical and physical properties were measured under the canopy of C. microphylla and in the adjacent open areas to determine the effects of individual shrubs on soil properties. The influence of isolated C. microphylla on chemical and physical properties of the topsoil was significantly different between plots under the shrub canopy and in the shrub interspaces. Beneath the shrub canopy greater amounts of fine particle fractions, a higher water-holding capacity, and a lower bulk density, as well as higher aboveground and belowground litter biomass were found. Soil organic C and total N concentrations were 23.-3..6% and 14%-27.2% higher under the shrub canopies than in the shrub interspaces, respectively, giving rise to 'islands of fertility'. In a desertified sandy grassland ecosystem, C. microphylla was believed to play a major role in organic C sequestration, N accumulation, and the hydrologic cycle. Additionally, it has been found to be of ecological importance for vegetative restoration and reversal of desertification.

关键词： Caragana microphylla Lam. degraded sandy grassland soil chemical properties soil physical properties

Processing technique of target capsule's micro inflation hole with a scanning probe

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Science china(Technological sciences) 2004年第1期47卷 77-84页

作者： SUN Tao, YAN Yongda, GAO Dangzhong, TANG Yongjian, FU Yibei & DONG ShenPrecision engineering research institute, Harbin institute of Technology, Harbin 150001, china research Centre of Laser Fusion, chinese academy of engineering Plysics, Mianyang 621900, china institute of Nuclear Physics and Chemistry, chinese academy of engineering Physics, Mianyang 621900, china 1. Precision engineering research institute Harbin Institute of Technology 150001 Harbin China 2. research Centre of Laser Fusion Chinese Academy of Engineering Plysics 621900 Mianyang China 3. institute of Nuclear Physics and Chemistry Chinese Academy of Engineering Physics 621900 Mianyang China

To resolve inflation of inertial confinement fusion (ICF) target and encapsulation of micro inflation hole with adhesive, a scanning probe microscope (SPM) diamond microprobe was used as the cutting tool with SPM in contact mode. Some parameters influencing the quality of micro inflation hole, such as the scanning direction of the diamond tip, the scanning rate and the contact force are discussed. Accurate taper hole was achieved whose climension and precision could meet the requirements of inflation and encapsulation technique of micro hole. The experimental results show that using SPM diamond microprobe as the cutting tool and with special processing technique, the precision machining of target capsule's taper inflation hole can be realized. A novel operative technology for filling high Z gas to target is provided.

关键词： target capsule, scanning probe microscope (SPM), diamond microprobe, processing technique, brittle material.

Sintering of Doped, Nanocrystalline CeO_2 Powders Prepared under Hydrothermal Conditions

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Journal of Materials Science & Technology 1995年第6期11卷 429-434页

作者： Yanchun ZHOU(institute of Metal research, chinese academy of sciences, Shenyang, 110015,{3.)M.N.Rahaman (Ceramic engineering Department, University of Missouri-Rolla, Rolla, MO 65401, USA) Inst of metal research Chinese Acad of Sciences Shenyang China

Nanocrystalline CeO2 powders (particle size ≈10-15 nm), doped with up to 20 at.-% of Mg,Ca or Y were prepared by chemical precipitation under hydrothermal conditions. The particle size and shape of the powders change slightly with the dopant concentrations. The the of the dopants on the sintering of the compacted powders was investigated during heating at a constant rate of 10℃/min. The elemental composition and the concentration of the dopant has significant efFect on the densification and grain growth. Compared to undoped CeO2, the dopants produce a shift in the densification curve to higher temperatures. For the same dopant concentration and under identical sintering conditions, the Ca doped samples reach nearly full density with the smallest grain size (≈50 nm), however, the Mg doped sample has the lowest density (≈95% of the theoretical) with the largest grain size (≈1 μm)

关键词： Brook TGA Nanocrystalline CeO2 Powders Prepared under Hydrothermal Conditions Sintering of Doped

Hydrological Characteristics of the Rongbuk Glacier Catchment in *** Region in the Central Himalayas,china

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Journal of Mountain Science 2010年第2期7卷 146-156页

作者： LIU Weigang REN Jiawen QIN Xiang LIU Jingshi LIU Qiang CUI Xiaoqing WANG Yetang State Key Laboratory of Cryospheric sciences Cold andArid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 10085 China

From 8 April to 11 October in 2005, hydrological observation of the Rongbuk Glacier catchment was carried out in the Mr. Qomolangma （Everest） region in the central Himalayas, china. The results demonstrated that due to its large area with glacier lakes at the tongue of the Rongbuk Glacier, a large amount of stream flow was found at night, which indicates the strong storage characteristic of the Rongbuk Glacier catchment. There was a time lag ranging from 8 to 14 hours between daily discharge peaks and maximum melting （maximum temperature）. As melting went on the time lag got shorter. A high correlation was found between the hydrological process and daily temperature during the ablation period. The runoff from April to October was about 80% of the total in the observation period. Compared with the discharge data in 1959, the runoff in 2005 was much more, and the runoff in June, July and August increased by 69%, 3.% and 14%, respectively. The rising of temperature is a major factor causing the increase in runoff. The discharges from precipitation and snow and ice melting are separated. The discharge induced by precipitation accounts for about 20% of the total runoff, while snow and ice melting for about 80%.

关键词： Central Himalayas Mt. Qomolangma Rongbuk Glacier Hydrological characteristics

Regional Summer Temperature Decrease against Global Warming in china, Landform Effect?

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Journal of Mountain Science 2007年第1期4卷 86-90页

作者： LU Aigang PANG Deqian HE Yuanqing PANG Hongxi WANG Tianming GE Jianping Ministry of Education Key Laboratory for Biodiversity Science and engineering College of Life SciencesBeijing Normal University Beijing 100875 China institute of C-eography research Weinan Teachers College Weinan 714000 Shaanxi China cold and arid regions Environmental and {3. institute Chinese Academy of SciencesLanzhou 730000 Gansu China

The data of 16o national meteorological observatory （NMO） stations with long-term monthly temperature data for china were analyzed in this study to show the basin-centered summer temperature decrease against global warming in the past half century. The summer and winter isotherm structures of 1950s and 1990s worked out by interpolation show the isotherm structure variations： the isotherm structure generally moves northward in winter, but in summer it is characterized with separate high-temperature and low-temperature centers and the isotherm structure moves inward the centers with global warming, indicating that the temperature in the highland areas increases but that in the lowland areas decreases in the summer of the duration. The possible mechanism of the basin-centered temperature decrease in summer is discussed in this paper.

关键词： Isotherm structure seasonal variation summer temperature decrease plateau-basin effect china

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敦煌地区大气气溶胶的辐射效应

太阳能学报 2004年第3期25卷 320-324页

作者：李韧季国良中国科学院寒区旱区环境与工程研究所兰州730000

利用敦煌地区1981～1983.地面实测的太阳直接辐射资料计算了该地区大气气溶胶的透射比及气溶胶对辐射削弱量,通过分析大气气溶胶的透射比与直接辐射、散射副射、S′/Q、D/Q的关系以及气溶胶对辐射削弱量与气温、直接辐射、气熔胶透射... 详细信息

利用敦煌地区1981～1983.地面实测的太阳直接辐射资料计算了该地区大气气溶胶的透射比及气溶胶对辐射削弱量,通过分析大气气溶胶的透射比与直接辐射、散射副射、S′/Q、D/Q的关系以及气溶胶对辐射削弱量与气温、直接辐射、气熔胶透射比的关系,讨论了大气气熔胶的辐射效应,得出了一些初步结论,随着气溶胶透射比的增大直接辐射、Q、S′/Q增大,D/Q减少;气溶胶对辐射的削弱增大时,气温减小,垂直于太阳光束面上的直接辐射减小,气溶胶透射比减小;在干旱地区晴空气溶胶对辐射的削弱占主导地位。

关键词：气溶胶辐射效应

Challenges and innovations in green process intensification

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Science china Chemistry 2010年第7期53卷 1470-1475页

作者： LIU HuiZhou,LIANG XiangFeng,YANG LiangRong & CHEN JiaYong institute of Process engineering,chinese {3. of sciences,Beijing 100190,china 1. institute of Process engineering Chinese Academy of Sciences Beijing 100190 China

Process intensification is one of the most significant trends in current chemical engineering and process *** recent years,the desire to become more "green" in processing has always been tied to the requirement of being *** review discusses the challenges of process engineering and summarizes the key role of fundamentals for green process intensification.

关键词： green chemistry process intensification

Seasonal transition and its boundary layer characteristics in Anduo area of Tibetan Plateau

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Progress in Natural Science:Materials International 2005年第3期 47-53页

作者： ZUO Hongchao ˇˇ ,HU Yinqiao,LI Dongliang,L Shihua and MA Yaoming (cold and arid regions Environmental and {3. research institute,chinese academy of sciences,lanzhou73.000,china) cold and arid regions Environmental and {3. research institute Chinese Academy of Sciences Lanzhou 730000 China

Using the data,especially the GPS rawinsode data,observed in Anduo area of the Tibetan Plateau during the intensive observation period of GAME/Tibet in1998,the transition from the dry to the rainy season along with their boundary layer characteristics is analyzed *** result shows that the formation of the rainy season in Anduo area is related closely to the general atmo-spheric *** westerly belt moving north and the southeast damp current are basic conditions for development of the rainy season in Anduo *** the dry season,the air is drier,air temperature higher,and the atmospheric boundary layer is strongly developed to cause its maximum height to reach *** the sensible heat flux is dominant,and the latent heat flux is small in the in-teraction of land-atmosphere energy exchange,and a reverse humidity phenomenon occurs *** the rainy season,the air is damper,air temperature lower,and the ABL height,with maximum of only about23.0m,is *** the sensible heat flux becomes much smaller,the latent heat flux much larger in the interaction of land-atmosphere energy *** reverse humidity phenomenon disappears.

关键词： dry season rainy season seasonal transition general atmospheric circulation land-atmosphere energy exchange.

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,{3. 2. institute of Forestry, chinese academy of Forestry sciences, Beijing 100091,{3. 3. Department of Civil engineering, University of Hong Kong, Hong Kong,{3. 4. Eco-environmental research Center, chinese academy of sciences, Beijing 100085,{3. 5. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716,{3. 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 53. 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 3.%.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.