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The reconstruction and interpretations of lake status at 6 ka and 1. ka *** inland mainland Asia

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chinese Science Bulletin 1998年第14期43卷 1145-1157页

作者： QIN Boqiang 1. SHI Yafeng 1.and YU Ge 2, 3.1. Nanjing {1. of Geography & Limnology, chinese Academy of Sciences, Nanjing 21.008, china 2. Dynamic Palaeoclimatology, Lund University, PO Box 1.7, S 221.00, Lund, Sweden 3. Department of Nanjing institute of Geography & Limnolagy Chinese Academy of Sciences Nanjing China Dynamic Palaeoclimatology Lund University Lund Sweden Department of Geology and Ocean Sciences Nanjing University Nanjing China

By means of survey of literature through compilations of sedimentological, biogeological and geomorphologic data, the inland lake level changes in arid or semi arid mainland Asia at 6 and 1. ka B.P. have been reconstructed. The results showed that the lakes from western and northwestern Asia were characterized by very high water levels at 1. ka B.P., but low or intermediate water stands at 6 ka B.P. The high lake level in this region was associated with the southward displacement of westerlies, therefore, the extent of the high lake stand indicated the southern flank of westerlies during the glaciation. conversely, the lakes from the eastern and southern Asia registered comparative low levels at 1. ka B.P. and significantly high one at 6 ka B.P. The lowering of lake level at 1. ka B.P. was caused by the weakened summer monsoon and the high lake level at 6 ka B.P. by the enhanced summer monsoon induced by the enlarged thermal contrast between land and ocean. The extent of high lake levels indicated the northern boundary of monsoon expansion. Between the above two regions, there is a climatic transitional zone in the central Asia where the lake behavior was close to that in southeastern Asia at 6 ka B.P. but became similar to that in northwestern Asia at 1. ka B.P. Thus this zone became a transitional sector from the monsoon to the westerlies.

关键词： lake status inland mainland Asia westerlies monsoon.

A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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Science china Earth Sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1. YE Baisheng2, ZHOU Yuhua3.& TIAN Fuqiang1.1. Department of Hydraulic Engineering, Tsinghua University, Beijing 1.0084,{1.hina 2.{1.old and Arid Regions Environmental and Engineering Research institute,{1.hinese Academy of Sciences, Lanzhou 73.000,{1.hina 3. Department of{1.ivil Engineering, Massachusetts institute of Technology, USA 1. Department of Hydraulic Engineering Tsinghua University Beijing 100084 China 2. cold and Arid Regions Environmental and Engineering Research {1. Chinese Academy of Sciences Lanzhou 730000 China 3. Department of{1.ivil Engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1.98. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science china Earth Sciences 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1. BAI Zhiming1. WANG chunyong2, TENG Jiwen1. Lü Qingtian{1. LI Jiliang1. SUN Shanxue1.& WANG Xinzheng1.1. institute of Geology and Geophysics, chinese Academy of Sciences, Beijing 1.0029, china 2. institute of Geophysics, chinese Seismological Bureau, Beijing 1.0081. china {1. institute of Deposition Resource, chinese Academy of Geological Sciences, Beijing 1.00{1., china 1. institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of Geophysics Chinese Seismological Bureau 100081 Beijing China 3. {1. of Deposition Resource Chinese Academy of Geological Sciences 100037 Beijing China

The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the Yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 40 km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.

关键词： Gondwana blocks,Yangtze blocks,wide-angle profile,crustal structure,tectonic setting

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1.2 , XIANG Jianhai 1.*, WANG Bing 1.2 , LI Fuhua 1.and TONG Wei 3.1. Experimental Marine Biology Laboratory, {1. of Oceanology, chinese Academy of Sciences, Qingdao 266071.china 2. Graduate School of the chinese Academy of Sciences, Beijing 1.003., china 3. Genomics & Bioinformatics {1., chinese Academy of Sciences, Beijing 1.1.0}0, china) chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 1.446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

Distribution and fractionation mechanism of stable carbon isotope of coalbed methane

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Science china Earth Sciences 2006年第12期49卷 1252-1258页

作者： QIN Shengfei1. TANG Xiuyi2, SONG Yan1.& WANG Hongyan3.1. Research {1. of Petroleum Exploration and Development, Petrochina, Beijing 1.0083. china 2. Anhui Science and Technology college, Huainan 23.000, china 3. Langfang Branch, Research {1. of Petroleum Exploration and Development, Petrochina, Langfang 065007, china 1. Research institute of Petroleum Exploration and Development PetroChina Beijing 100083 China 2. Anhui Science and Technology college Huainan 232000 China 3. Langfang Branch Research Institute of Petroleum Exploration and Development PetroChina Langfang 065007 China

The stable carbon isotope values of coalbed methane range widely, and also are gener- ally lighter than that of gases in normal coal-formed gas fields with similar coal rank. There exists strong carbon isotope fractionation in coalbed methane and it makes the carbon isotope value lighter. The correlation between the carbon isotope value and Ro in coalbed methane is less obvious. The coaly source rock maturity cannot be judged by coalbed methane carbon isotope value. The carbon isotopes of coalbed methane become lighter in much different degree due to the hydrodynamics. The stronger the hydrodynamics is, the lighter the cBM carbon isotopic value becomes. Many previous investigations indicated that the desorption-diffusion effects make the carbon isotope value of coalbed methane lighter. However, the explanation has encountered many problems. The authors of this arti- cle suggest that the flowing groundwater dissolution to free methane in coal seams and the free methane exchange with absorbed one is the carbon isotope fractionation mechanism in coalbed methane. The flowing groundwater in coal can easily take more 1.26}H4 away from free gas and com- paratively leave more 1.cH4. This will make 1.cH4 density in free gas comparatively higher than that in absorbed gas. The remaining 1.cH4 in free gas then exchanges with the adsorbed methane in coal matrix. Some absorbed 1.26}H4 can be replaced and become free gas. Some free 1.cH4 can be ab- sorbed again into coal matrix and become absorbed gas. Part of the newly replaced 1.26}H4 in free gas will also be taken away by water, leaving preferentially more 1.cH4. The remaining 1.cH4 in free gas will exchange again with adsorbed methane in the coal matrix. These processes occur all the time. Through accumulative effect, the 1.cH4 will be greatly concentrated in coal. Thus, the stable carbon isotope of coalbed methane becomes dramatically lighter. Through simulation experiment on wa- ter-dissolved methane, it had been proved that the f

关键词： coalbed methane,methane stable carbon isotope,fractionation mechanism,accumulative effect.

Mesozoic-cenozoic tectonic transition in Kuqa Depression-Tianshan,Northwest china:Evidence from sandstone detrital and geochemical records

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Science china Earth Sciences 2005年第9期48卷 1387-1402页

作者： LI Zhong1. GUO Hong2, WANG Daoxuan3.& LIN Wei1.1. {1. of Geology and Geophysics, chinese Academy of Sciences, Beijing 1.0029, china 2. Tarim Oilfield Branch, cNPc, Korla 841.00, china 3. Hefei University of Industry, Tunxilu 1.3. Hefei 23.009, china 1. institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing Chin 2. Tarim Oilfield Branch CNPC 841000 Korla China 3. Hefei University of Industry Tunxilu 193 230009 Hefei Chin

Similar to compositional evolution of sandstone modes and detrital heavy minerals from different profiles in the Kuqa Depression, Northwest china, major element analysis of whole sandstones from the same profiles shows four discontinuous depositional interfaces or periods, respectively corresponding to Lower Triassic\Middle Triassic, Upper Jurassic\Lower cretaceous, Lower cretaceous\Paleogene and Miocene\Pliocene, and indicates five-phase evolution during Mesozoic-cenozoic: (1) From the first to fifth phase, a depositional suite changes from maroon and coarse clastic, through grey-dark grey and fine, red and coarse, red-mottled, interlayered by gypsum, to brown and coarse clastic assemblages, accompanying detrital component evolution in unstable-stable-unstable-very unstable-very unstable assem- blages. It is indicated that carbonate and complex detritus gradually dominate in sandstones in post-Late Jurassic, with rapid reduction of compositional maturity. (2) For major element geo- chemical parameters of whole sandstones, caO and Fe2 O * 3.MgO contents show a change sequence in high-low-high-higher-highest values, with rapid increasing in post-Late Jurassic. (3. contra some aggregative indicators for weathering indexes of sandstone detrital component, Al2O3.(caO+Na2O) and ln(Q/(L+cE)), show a change sequence in low-high-low-lower-lowest ratios, with rapid decreasing in post-Late Jurassic. It is found that sandstone samples of the first, second and later three phases may be distinguished from the A-cN-K and A-cNK-FM diagrams respectively. Therefore, in the Kuqa Depression-Tianshan, the most important discontinuous depositional interface recording paleotectonic and paleoclimatic transition occurred in Early Triassic\Middle Triassic and Late Jurassic\Early cretaceous, respectively, and, however, tec- tonic differentiations of basin-range system finally result in distinct depositional systems but similar detrital weathering indexes across the Lower cretaceous\Paleogene

关键词： Tianshan, Kuqa Depression, basin-range, depositional record, tectonic transition, Mesozoic-cenozoic.

Rose solutions with three petals for planar 4-body problems

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Science china {1. 2010年第12期53卷 3085-3094页

作者： DENG chunHua 1.2 , ZHANG ShiQing 1. & ZHOU Qing {1.1.Yangtze center of mathematics and college of mathematics, Sichuan University, chengdu 61.064, china 2 Faculty of mathematics and Physics, Huaiyin institute of Technology, Huai’an 22{1.01. china {1.Department of mathematics, East china Normal University, Shanghai 200062, china 1. Yangtze center of {1. and college of {1. Sichuan University Chengdu 610064 China2. Faculty of Mathematics and Physics Huaiyin Institute of Technology Huai’an 223001 China3. Department of Mathematics East China Normal University Shanghai 200062 China

For planar Newtonian 4-body problems with equal masses, we use variational methods to prove the existence of a non-collision periodic choreography solution such that all bodies move on a rose-type curve with three pet... 详细信息

关键词： 4-body problems with Newtonian potentials rose solutions with three petals winding numbers variational minimization methods

Deposition features of Ni on self-assembled microtubule template from biolipid by electroless method

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Science china chemistry 2004年第3期47卷 228-234页

作者： FU Yubin1.2, ZHANG Lide1. ZHENG Jiyong2, FU Shangang3.& ZHU Mingwei3.1. institute of Solid State Physics, chinese Academy of Sciences, Hefei 23.03., china 2. Luoyang Ship Material Research institute, Luoyang 471.3., china 3. college of Life Science, Henan Normal University, Xinxiang 453.02, china 1. institute of Solid State Physics Chinese Academy of Sciences 230031 Hefei China 2. Luoyang Ship Material Research institute 471039 Luoyang China 3.{1.ollege of Life Science Henan Normal University 453002 Xinxiang China

Diacetylenic glycero-phosphatidylcholine is a chiral molecule with amphiphilic property, and it can self-assembly into a lipid microtubular structure. The lipid microtubule is a stable structure formed by tightly wound helical ribbons, and the ribbon-wrapping patterns have a significant effect on their chemical deposition on the microtubules. The deposition of colloidal Pd catalyst occurs mainly on the helical edge of the wound helical ribbons to form helical deposition lines of colloidal Pd particles in the interior and exterior of the lipid microtubules, resulting in an uneven chemical deposition of Ni on the microtubules. catalyzed by as-deposited colloidal Pd, metallized Ni microtubules are characterized by a helical form, which may be in relation to inner stress due to the thickness difference or the different deposition processes. The observation of microtom shows that metallized tubules have a hollow structure. Some metallized tubules have a kind of coaxial double layer structure observed in the direct experiment evidence, indicating that metallization can occur in the inner and outer surface of the lipid tubules. Both lipid microtubules and metallized microtubules can be used as vehicles for encapsulating biological active molecules to control their release and to develop micro-components in biological and mechanical systems. Keywords molecular self-assembly - lipid microtubules - helical pattern - site-specific deposition - electroless metallization

关键词： molecular self-assembly, lipid microtubules, helical pattern, site-specific deposition, electroless metallization.

Determination of tectonic background for sedimentary basin from sandstone geochemistry

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chinese Science Bulletin 1998年第14期43卷 1191-1196页

作者： SHAO Lei 1. K. Stattegger 2 and LI Wenhou 3.1. Laboratory of Marine Geology, Tongji University, Shanghai 200092,{1.hina 2. Geological and Paleontological institute, University of Kiel, 241.8 Kiel, Germany 3. Department of Geology, Northwest Unive Laboratory of Marine Geology Tongji University Shanghai China Geological and Paleontological institute University of Kiel Kiel Germany Department of Geology Northwest University Xi’an China

The chemical composition of sedimentary rocks is mainly controlled by source rocks. Through examining chemical composition of terrigenous rocks, the tectonic evolution of a sedimentary basin can be modeled. The Turpan Basin belongs to a continental sedimentary basin and its source rocks are derived from the upper continental crust.

关键词： sedimentary rock geochemistry basin analysis Turpan Basin.