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Growth of Carbon Encapsulated Long Nickel Nanorods on Bulk Nickel Substrate

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Journal of Wuhan University of Technology(Materials Science) 2011年第1期26卷 28-32页

作者：宾晓蓓 College of Resources & environment Engineering Wuhan University of Technology

Carbon nanotube encapsulated nickel nanorods were catalytic grown via pyrolysis of oil on a bulk nickel wire substrate. X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy and Raman spectroscopy were employed to characterize the as-prepared sample. The results show that, carbon nanotubes possess several microns in length, the filled metallic nickel nanorods with a uniform diameter of 3. nm were tightly encapsulated by the carbon capsules. The detailed formation mechanism for the carbon nanotubes encapsulated nickel nanorods were discussed briefly.

关键词： carbon nanotube nickel nanorod pyrolysis core-shell

Simulating Hydrologic Changes with Climate Change Scenarios in the Haihe River Basin

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Pedosphere 2005年第5期15卷 53-58页

作者： YUAN Fei 1,2, XIE Zheng-Hui1,* 2, LIU Qian1 and XIA Jun 3.1LASG, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029 (china). 2 College of Water Resources and environment, Hohai University, Nanjing 210098 (china)3.institute of Geographical Science & Natural Resources, Chinese Academy of Sciences, Beijing 100101 (china) institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 （china）. 2 College of Water Resources and environment Hohai University Nanjing 210098 （china）3.institute of Geographical Science & Natural Resources Beijing 100101 （china）

Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3.) land surface model forthe simulation of hydrologic processes at a spatial resolution of 0.25° × 0.25° in the Haihe River Basin. Three climatescenarios were considered in this study: recent climate (1961-1990), future climate A2 (1991-2100) and future climateB2 (1991-2100) with A2 and B2 being two storylines of future emissions developed with the Intergovernmental Panel onClimate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2 and B2, theHaihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production ascompared with recent climate, but would be still likely prone to water shortages in the period of 203.-2070. In addition,under future climate A2 and B2, an increase in runoff during the wet season was noticed, indicating a future rise in theflood occurrence possibility in the Haihe River Basin.

关键词： climate change regional climate modeling system runoff VIC-3. model

Palaeoenvironmental implication of the Plio-Pleistocene loess deposits in southern Tarim Basin

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Chinese Science Bulletin 2002年第8期47卷 700-704页

作者： ZHENG Hongbo, CHEN Huizhong & CAO JunjiLaboratory of Marine Geology, Tongji University, Shanghai 200092, china institute of Earth environment, Chinese Academy of Sciences, Xi’an 710054, china institute of environment and Engineering of Cold and Arid Regio Laboratory of Marine Geology Tongji University Shanghai 200092 China

The sedimentary characteristics, grain-size distribution, geochemical composition and surface characteristics of quartz grains, together with palaeoenvironmental reconnaissance, all point to an aeolian origin for the intercalated siltstone beds in the Plio-Pleistocene Artux and Xiyu Formations along the southern margins of the Tarim Basin, indicating that loess deposition in the region started, at least, in the Early Pliocene. Loess deposition in the southern Tarim Basin was a response to the global deterioration, which might be attributed to the uplift of the Tibetan Plateau.

关键词： eolian loess Plio-Pleistocene Tarim Basin.

Geochemical characteristics of pyrolysis gas from epimetamorphic rocks in the northern basement of Songliao Basin,Northeast china

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Science china Earth Sciences 2008年第S1期51卷 140-147页

作者： YANG Chun 1 ,LUO Xia 2 ,LI Jian 2 ,LI ZhiSheng 2 ,LIU QuanYou 3.&Wang YuLin 4 1 Department of Earth Sciences,Zhejiang University,Hangzhou 3.0027,china 2 Research institute of Petroleum Exploration and Development(Langfang Branch),Langfang 065007,china 3.Research institute of Petroleum Exploration and Development,Beijing 100083.china 4 Department of Source and environment,Liaoning Technical University,Fuxin 123.00,china Zhejiang Univ Dept Earth Sci Hangzhou 310027 Peoples R China Res Inst Petr Explorat & Dev Langfang Branch Langfang 065007 Peoples R China Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China Liaoning Tech Univ Dept Source & Environm Fuxing 123000 Peoples R China

The Xushen gas field,located in the north of Songliao Basin,is a potential giant gas area for china in the *** proved reserves have exceeded 1000×10 8 m 3.by the end of ***,the origin of natural gases from the deep strata is still in *** rocks as a potential gas source are widely spreading in the northern basement of Songliao *** to pyrolysis experiments for these rocks in the semi-confined system,gas production and geochemistry of alkane gases are discussed in this *** Carboniferous-Permian epimetamorphic rocks were heated from 3.0℃to 550℃,with temperature interval of 50℃.The gas production was quantified and measured for chemical and carbon isotopic *** show thatδ13. 1 is less than?20‰,carbon isotope trend of alkane gas isδ13. 1 3. 2 3. 3.orδ13. 1 3. 2 >δ13. 3.,these features suggest that the gas would be coal-type gas at high-over maturity,not be inorganic gas with reversal trend of gaseous alkanes (δ13. 1 >δ13. 2 >δ13. 3.).These characteristics of carbon isotopes are similar with the natural gas from the basin basement,but disagree with gas from the Xingcheng ***,the mixing gases from the pyrolysis gas with coal-typed gases at high-over maturity or oil-typed gases do not cause the reversal trend of carbon *** gas generation intensity for epimetamorphic rocks is 3.0×10 8 ―23.8×10 8 m 3./km 2 ,corresponding to Ro from 2.0%to 3.5%for organic matter.

关键词： Northern Songliao Basin epimetamorphic rock pyrolysis experiment gas generation potential carbon isotope

Neogene eolian deposits within the West Qinling Mountains:Climatic and tectonic implications

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Chinese Science Bulletin 2010年第15期55卷 1483-1487页

作者： GE JunYi 1,2 & GUO ZhengTang 3.1 State Key Laboratory of Loess and Quaternary Geology (SKLLQG),institute of Earth environment,Chinese Academy of Sciences,Xi’an 710075,china 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,china 3.Key Laboratory of Cenozoic Geology and environment,institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,china State Key Laboratory of Loess and Quaternary Geology (SKLLQG) Institute of Earth Environment Chinese Academy of Sciences Xi''an 710075 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Cenozoic Geology and environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

The Qinling Mountains constitute a key climate barrier between southern and northern *** recent investigations revealed widely spread eolian deposits of Neogene age mantling the piedmont highlands of the intermountain basins within West ***-mammalian fossils dated a 150.2 m section (NL-VI) near Xihe for the late Miocene to Pliocene (～10-4 Ma).Soil micromorphology,grain-size and geochemical analysis consistently define typical loess-soil alternations for the upper (0-66 m) and lower (98-150.2 m) parts of the section,with the middle section (66-98 m) having been affected by episodic slope *** results add important insights to the earlier studies about the widespread eolian deposition in northern china during the Miocene,prior to 8 *** also suggest that the basic configuration of the ridges and inter-ridge basins of West Qinling has already formed by ～10 *** well-preserved eolian deposits are unlikely to support intense substratum deformation and rapid uplift of West Qinling since the late Miocene.

关键词：秦岭山脉风尘堆积构造意义气候新近纪晚中新世地球化学分析风尘沉积

Distributions of fatty acids in a stalagmite related to paleoclimate change at Qingjiang in Hubei,southern china

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Science china Earth Sciences 2005年第9期48卷 1463-1469页

作者： XIE Shucheng1,HUANG Junhua1,WANG Hongmei2,YI Yi1,HU Chaoyong1, CAI Yanjun3.& CHENG Hai4 1. Faculty of Earth Science,china University of Geosciences,Wuhan 43.074,china 2. School of environmental Studies,china University of Geosciences,Wuhan 43.074,china 3. SKLLQG,institute of Earth environment,Chinese Academy of Sciences,Xi’an 710075,china 4. Department of Geology and Geophysics,University of Minnesota,MN55455,USA 1. Faculty of Earth Science China University of Geosciences 430074 Wuhan China 2. School of environmental Studies China University of Geosciences 430074 Wuhan China 3. SKLLQG Institute of Earth Environment Chinese Academy of Sciences 710075 Xi’an China 4. Department of Geology and Geophysics University of Minnesota 55455 MN USA

Fatty acids extracted from a subtropical stalagmite at Qingjiang in Southern china’s Hubei Province were analysed using gas chromatography-mass spectrometry. These n-alkanoic acids range from C14 to C26 in carbon number, maximizing at C16, with a second dominance at C22. In contrast to the stalagmite analysed, the overlying soils are characterized by the dominance of heavy-molecular-weight homologues (>C20). The n-fatty acids in the stalagmite were proposed to be contributed by both the soil ecosystems and the microbes harboring in the percolating water and the cave. The ratios of unsaturated to saturated n-fatty acids (C16:1i/C16:0, C18:1/C18:0) appear to show trends comparable with the oxygen isotope records of the stalagmite carbonate, with enhanced values associated with the cold episode such as Heinrich event 1. This paleoclimate-dependent record of the n-fatty acids might reflect microbial changes in physiology and activity in response to the temperature. This record shows somewhat difference from the previous paleoclimate signal extracted from n-alkanols and n-alkan-2-ones of the same stalagmite. The acid record fails to document the well-known Younger Dryas event which was effectively shown by the latter two biomarkers derived from soil ecosystems. This discrepancy might result from the changing biogeochemical impact on different lipid fractions as well as the varied organism populations in different ecosystems.

关键词： biomarker, ecosystem, microbe, speleothem, paleoclimate, Quaternary.

Magnetostratigraphy of Late Cenozoic fossil mammals in the northeastern margin of the Tibetan Plateau

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Science Bulletin 2003年第2期48卷 188-193页

作者： SONG Chunhui1,2,FANG Xiaomin 1,2,GAO Junping1, NIE Junsheng1,YAN Maodu1,3.XU Xianhai1 & SUN Dong1 1. MOE National Laboratory of Western china抯 environmental Systems & College of Resource and environment,Lanzhou University,Lanzhou 73.000,{3. 2. State Key Laboratory of Loess and Quaternary Geology ,institute of Earth environment,Chinese Academy of Sciences,Xi抋n 710075, china 3. Department of Geological Sciences,University of Michigan,AnnArbor,MI 48109,USA Univ Arizona Steward Observ Tucson AZ 85721 USA MOE National Laboratory of Western china\'s environmental Systems & College of Resource and environment Lanzhou University Lanzhou 730000 China

A number of fossil mammals have been found in the very thick Cenozoic stratigraphy of the Guide Basin in the northeastern margin of the Tibetan *** of these are of great significance in mammal evolution and stratigraphic correla-tion on and around the Tibetan Plateau and North ***,the chronology of these mamals is poorly *** of the mammals will not only place precise age constraints on the mammals,but also provide much inlormation on the related stratigraphy that records the uplift process of the Tibetan *** paleomagnetism of the upper part of the Cenozoic stratigraphy at He'erjia and Lajigai north of Guide County has revealed magnetic chrons that can be correlated to Ganss and 3.n *** the section spanning about 3.16.5 Ma and the *** and third layers of fossil mammals at about 5.25,5.1 and 4.4 Ma,*** of the significant genus Gazella kueitensis and the Chinese elephant Anancus sinensis are firstly constrained at about 5.25 MaBP and 4.4 Ma,*** mammalian evolution and the associated increase in coarse sediments and sedimentation rate may suggest that the northeastern Tibetan Plateau was uplifted rapidly at that time,and the eastern Tibetan Plateau with its neighboring regions was not high enough to stop mammal exchange between the northern and southern sides of the Tibetan Piateau.

关键词： Tibetan Plateau Guide Basin Late Cenozoic stratigra-phy fossil mammals paleomagnetism.

Variation of grain Cd and Zn concentrations of 110 hybrid rice cultivars grown in a low-Cd paddy soil

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Journal of environmental Sciences 2009年第2期21卷 168-172页

作者： SHI Jing,LI Lianqing,PAN Genxing institute of Resource,Ecosystem and environment of Agriculture,Nanjing Agricultural University,Nanjing 210095,china. institute of Resource Ecosystem and Environment of Agriculture Nanjing Agricultural University Nanjing 210095 China

Enhanced Cd uptake and Zn depletion in rice grains and high potential for food Cd exposure by the high-yielding hybrid cultivars of china had been addressed. A field experiment was conducted in 2006 to determine the difference in grain Cd and Zn between cultivars. Total 110 cultivars including super rice and common hybrid rice cultivars were grown on a single paddy soil （Entic Haplaquept） with a neutral reaction and low total Cd content. Grain Cd and Zn concentrations were determined with graphite atomic adsorption spectrophotometer （GFAAS） and flame atomic adsorption spectrophotometer （AAS） respectively. Wide variation of Cd content in grain was found in a range of 0.004-0.057 mg/kg, while the Zn content in a range of 10.25-3..06 mg/kg among the cultivars. Higher Cd but lower Zn concentration in grains of super rice cultivars was observed compared to the common hybrid ones. A highly significant positive linear correlation of grain Cd/Zn with grain Cd was found for super rice and common hybrid cultivars, meanwhile much higher slope for these hybrid cultivars than the reported non-hybrid cultivars was also observed. Using the limit value of the Chinese chemical guidelines for foods （MOHC and SSC, 2005）, calculated potential risk of food Cd exposure with ＂Zn hungry＂ through diet intake was prominent with all the studied 110 hybrid rice cultivars, possessing high potential health problems for rice production in South china using the super rice cultivars. Breeding of genotypes of rice cultivars with low grain Cd and low Cd/Zn ratio is needed for rice production in acidic red soils where Cd bioavailability is prevalently high.

关键词： rice cultivar rice grain cadmium zinc genotype difference

Temporal variations of δ^(18)O of atmospheric water vapor at Delingha

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Science china Earth Sciences 2008年第7期51卷 966-975页

作者： YIN ChangLiang1, YAO TanDong2, TIAN LiDe2, LIU DongNian3. YU WuSheng2 & QU DongMei2 1 State Key Laboratory of Cryoshperic Science, Cold and Arid Regions environmental and Engineering Research institute, Chinese Academy of Sciences, Lanzhou 73.000, china 2 Laboratory of environment and Processes, institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, china 3.Meteorological Observatory of Haixi Prefecture of Qinghai Province, Delingha 817000, china 1. State Key Laboratory of Cryoshperic Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. Laboratory of environment and Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 3. Meteorological Observatory of Haixi Prefecture of Qinghai Province Delingha 817000 China

Oxygen stable isotope of atmospheric water vapor is widely used to study the modern process of cli- mate. Atmospheric water vapor samples were collected at Dlingha, northeast of Tibetan Plateau during the period from July 2005 to February 2006. The variation of δ18O and the relationships between δ18O and both the temperature and specific humidity are analyzed in this paper. Results show that the sea- sonal variation of δ18O of atmospheric water vapor at Delingha is remarkable with higher δ18O in summer and lower δ18O in winter. The temporal variation of vapor δ18O shows obvious fluctuations, with magnitude of over 3.‰. The daily variation of the δ18O is highly correlated with air temperature. The relationship between δ18O and atmospheric water vapor content is complex. Study shows that δ18O of atmospheric water vapor is positively correlated with specific humidity in winter in seasonal scale and inversely correlated with specific humidity in summer rainy period. The δ18O values of at- mospheric water vapor are lower than those of precipitation at Delingha, and the average difference is 10.7‰. Variations of δ18O of atmospheric water vapor is also found to be affected by precipitation events, The model results show that the precipitation effect could have caused the vapor δ18O in the raining season to lower by 7% in average in July and August.

关键词： Delingha δ18O atmospheric water vapor