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Geomorphologic evidence of phased uplift of the northeastern Qinghai-Tibet Plateau since 14 million years ago

science China Earth sciences 2004年第9期47卷 822-833页

作者： LU Huayu1, WANG Xiaoyong1, AN Zhisheng1, MIAO Xiaodong1, ZHU Rixiang3, MA Haizhou2, LI Zhen4, TAN Hongbing2 & WANG Xianyan1 1. State Key Laboratory of Loess and Quaternary Geology, institute of Earth Environment, Chinese Academy of sciences, Xi’an 710075 China 2. Qinghai institute of Salt Lakes, Chinese Academy of sciences. Xining 810008, China 3. institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, China 4. Department of geography, Qinghai Normal University, Xining 810008, China Chinese Acad sci Inst Earth Environm State Key Lab Loess & Quaternary Geol Xian 710075 Peoples R China Chinese Acad sci Qinghai Inst Salt Lakes Xining 810008 Peoples R China Chinese Acad sci Inst Geol & Geophys Beijing 100029 Peoples R China Qinghai Normal Univ Dept Geog Xining 810008 Peoples R China

A typical sequence of fluvial terraces and aeolian deposits overlying these ter- races were multidisciplinary investigated. New evidences for uplift process of the northeastern Qinghai-Tibetan Plateau in the past 14 million years were obtained. At least 11 river terraces along Huangshui, the first-class tributary of Yellow River, at the Xining-Huzhu region are identi- fied. While the first one (T1) is classified as an accumulation terrace, the others are all basement river terraces, which consist of the Tertiary sandstone and siltstone bedrock, fluvial gravel and pebbles and the overlying aeolian loess-Red Clay deposit. Samples from the aeolian deposits were examined for paleomagnetic stratigraphic reconstruction (1030 samples), luminescence dating (16 samples), magnetic susceptibility and grain-size distribution (more than 4000 sam- ples). The luminescence dating and stratigraphic correlation suggest that terraces of Tll, T10, T8, T7, T3, T2, T1 were formed at 14, 11.3, 1.55, 1.2, 0.15, 0.07 and 0.01 million years ago, re- spectively. Sedimentological analysis and geomorphological observation indicate that formation and evolution of these terraces were mainly driven by tectonic uplift. Therefore, the terrace se- quence provides an ideal geological record, of the uplift process of the northeastern during the past 14 million years, and the timings of the terraces formation are regarded as the timings of tectonic uplift. The significant uplifting events took place at 14, 11.3, 1.2 and 0.15 mil- lion years ago, respectively. The fluvial incision at the Xining-Huzhu region is less than 100 m during a period of ~12 million years in the Miocene era (between the Tll and T9), while the Huangshui River had incised 432 m during the past 1.2 million years (from T7 to the present floodplain). The river incision process clearly demonstrates that accelerated rising of the north- eastern Qinghai-Tibet Plateau during the late Cenozoic, and provides new evidence of previous thoughts

关键词： river terrace, tectonic uplift, loess-Red Clay, the past 14 million years, northeastern Qinghai-Tibet Plateau.

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Chemical synthesis of a structural gene coding for trichosanthin

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Chinese Journal of Chemistry 1995年第4期13卷 349-357页

作者： CHEN, HB XIA, Y JING, JP JIANG, K BAO, JS CHINESE ACAD sci SHANGHAI INST ORGAN CHEMCOMP CHEM LABSTATE KEY LAB BIOORGAN & NAT PROD CHEMSHANGHAI 200032PEOPLES R CHINA

A structural gene (750 bp), which codes for a type I ribosome inactivating protein, trichosanthin, has been designed according to the codon usage of highly expressed gene in E. coli and chemically synthesized. In the synthesized gene, twenty-seven unique restriction sites were evenly dispersed with an average distance between two adjacent sites less than 50 bp to facilitate a systematic investigation on structure-functional relationship of this protein by site-directed mutagenesis. To synthesize it, the whole gene was divided into three large fragments (EP, PN and NH) which were assembled from several chemical synthetic oligonucleotides by enzymatic method. The assembly of both the fragment EP from six oligonucleotides (A-F) and the fragment PN from four oligomers (G-J) was catalyzed by T-4 DNA ligase in using the single stranded DNA method [Chen, H.-B. et al., Nucl. Acids Res., 18, 871(1990)]. And fragment NH was formed from three duplexes K, L and M by the classical double stranded DNA method. Finally, each fragment was cloned into vector pUC18 in succession to form the plasmid, pC0TCS, to complete the whole gene synthesis, The sequencing data for the synthetic gene coincides with the designed one.

关键词： RIBOSOME INACTIVATING PROTEIN TRICHOSANTHIN GENE DESIGN GENE SYNTHESIS SYNTHETIC GENE

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Effects of sodium on nitrate uptake and osmotic adjustment of Suaeda physophora

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Journal of Arid Land 2010年第3期2卷 190-196页

作者： Yuan, JunFeng Tian, ChangYan Feng, Gu Chinese Acad sci Xinjiang Inst Ecol & Geog Key Lab Oasis Ecol & Desert Environm Urumqi 830011 Peoples R China China Agr Univ Coll Resource & Environm Sci Beijing 100094 Peoples R China

Na+ ions play an important role in the growth of halophyte. The effect of Na+ ions on nitrate uptake and osmotic adjustment in the euhalophyte Suaeda physophora was investigated under glasshouse conditions. Seedlings were exposed to 1 mmol/L NaCl (control),300 mmol/L NaCl,150 mmol/L NaCl plus 150 mmol/L KCl or 300 mmol/L KCl treatments for 24 d. Dry weight was not affected greatly by different salt treatments,but water content and succulence in leaves of S. physophora were significantly increased at 300 mmol/L NaCl and 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The concentrations of Na+ and NO3’ in leaves of S. physophora were the highest at 150 mmol/L NaCl plus 150 mmol/L KCl,but lowest at 300 mmol/L KCl treatment. Moreover,the increase of NO3’ concentration did not result in the decrease of Cl-concentration at 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The estimated contribution of NO3’ to osmotic potential (CNO3) in leaves of S. physophora was 9.8% at 150 mmol/L NaCl plus 150 mmol/L KCl,and CNa and CCl were 31.0% and 23.3%,respectively. However,CNO3,CNa and CCl were respectively 1.6%,7.9% and 11.9% at 300 mmol/L KCl treatment. It is concluded that Na+ stimulates NO3’ absorption and the stimulation is independent on the internal or the external Cl-concentration in the euhalophyte S. physo-phora. These characteristics may explain the high levels of N in leaves of saline desert plants in arid ecosystem.

关键词： euhalophyte Suaeda physophora NaCl KCl NO3’

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Characteristics and dynamics analysis of Populus euphratica populations in the middle reaches of Tarim River

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Journal of Arid Land 2010年第4期2卷 250-256页

作者： Wu, JunXia Zhang, XiMing Deng, ChaoZhou Liu, GuoJun Li, Hong Chinese Acad sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China Chinese Acad sci Grad Univ Beijing 100049 Peoples R China Xinjiang Acad Forestry Urumqi 830000 Peoples R China

Populus euphratica Oliv. is widely distributed along the Tarim River. Maintaining stability of P. euphratica population is important to local development. This study explored the static life table, survivorship curves and four function curves (survival rate, cumulative mortality rate, mortality density, and hazard rate), and development index of P. euphratica population in the middle reaches of Tarim River. The results indicated that the age structure of P. euphratica population belonged to positive pyramidal type, which meant young age-class individuals occupied most populations. The number ofⅠ-Ⅱage classes accounted for 66.2% of whole population, and this indicated that there were abundant subsequent seedlings resources to support the growth of P. euphratica population in the middle reaches of Tarim River. The survivorship curve of P. euphratica belonged to the Deevey Ⅲ (concave-type) and the development index was 47.72%. Four function curves revealed that the individuals of P. euphratica sharply decreased at the initial stage and then leveled off at the late stage of survival curve. Time sequence prediction models predicted that the number of midlife individuals would increase in future 10, 20, 30 years, and P. euphratica population grew steadily as a result of rich saplings.

关键词： Populus euphratica population static life table survivorship curve survival analysis development index time sequence

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Using remote sensing to research Beijing wetlands dynamics

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science China(Technological sciences) 2006年第z2期49卷 97-107页

作者： ZHAO Wenji, GONG Zhaoning, GONG Huili, LI Xiaojuan, ZHANG Songmei & LI Jing Key Lab of Resource Environment and GIS of Beijing, Capital Normal University, Beijing 100037, China Northeast institute of geography and Agroecology, Chinese Academy of sciences, Changchun 130012, China College of resources science and Technology, Beijing Normal University, Beijing 100875, China Capital Normal Univ Key Lab Resource Environm Beijing 100037 Peoples R China Capital Normal Univ GIS Beijing Beijing 100037 Peoples R China Chinese Acad sci NE Inst Geog & Agroecol Changchun 130012 Peoples R China Beijing Normal Univ Coll Resources Sci & Technol Beijing 100875 Peoples R China

In Beijing, where wetlands are important to municipal freshwater conservation and biodiversity retention, three different types of wetlands were identified: riverside wetlands, wetlands surrounding lakes and reservoirs, and wetlands in municipal *** sensing technology was applied in combination with field investigations to monitor and analyze the changes in these wetlands, and a combination of fusion technologies,Landsat TM/ETM+ and IKONOS imaging, was used to investigate and map them. This study indicates that not only have wetland areas been reduced by half, but also their ecological environments have been degraded because of rapid economic development and population increase. Suggestions based on this research are made to reconstruct the ecological environment of the wetlands and return them to their previous state.

关键词： Beijing, wetland resource, remote sensing technology, ecological environment, dynamics.

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AN EFFICIENT AND STEREOSPECIFIC SYNTHESIS OF 1-PALMITOYL-2-[(z,z,z)-9,12,15-LINOLENOYL]-SNGLYCEROPHOSPHOCHOLINE

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Chinese Chemical Letters 1995年第10期6卷 863-866页

作者： Xia, J Hui, YZ Chinese Acad sci Shanghai Inst Organ Chem State Key Lab Bioorgan & Nat Prod Chem Shanghai 200032 Peoples R China

A polyunsaturated mixed-acid phosphatidylcholine,1-palmitoyl-2-linolenoy1 snglycerophosphocholine (1) Prepared from D-mannitol as an optically active starting materialis described.

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A Novel Compound From Ceratostigma Minus

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Chinese Chemical Letters 1998年第7期9卷 647-649页

作者： Jian Min YUE Yu ZHAO Qin Shi ZHAO Hou Ming WU Jing Fei XU Zhong Wen LIN Han Dong SUN(Laboratory of Phytochendstry, Kunming institute of Botany,Chinese Academy of sciences, Kunming 650204)(Shanghai institute of Materia Medica, Chinese Academy ofscienc Chinese Acad sci Kunming Inst Bot Lab Phytochem Kunming 650204 Peoples R China Chinese Acad sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China Chinese Acad sci Shanghai Inst Organ Chem State Key Lab Bioorgan & Nat Prod Chem Shanghai 200032 Peoples R China

A novel compound, plumbocatechin A 1, was isolated from the whole plant of Ceratostigma minus. The structural elucidation of 1 was mainly achieved by 2D-NMR techniques.

关键词： Ceratostigma minus plumbocatechin A

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STELLADELIN A, A NEW CYCLOPEPTIDE FROM STELLARIA DELAVAYI

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Chinese Chemical Letters 1995年第12期6卷 1041-1044页

作者： Yu Rui ZHAO Jun ZHOU Xiang Kai WANG Hou Ming WU Xiao Lin HUANG (Department of Medicinal Chemistry of natural Produdts, School ofPharmacy, West China University of Medical sciences, Chengdu, 610041)(Laboratory of Phytochemistry, Kunming institute of Bo W China Univ Med sci Sch Pharm Dept Med Chem Nat Prod Chengdu 610041 Peoples R China Chinese Acad sci Kunming Inst Bot Lab Phytochem Kunming 650204 Peoples R China Chinese Acad sci Shanghai Inst Organ Chem State Key Lab Bioorgan & Nat Prod Chem Shanghai 200032 Peoples R China

From the fresh roots of Stellaria delavayi, a new cyclic undecapeptide, na nely stelladelin A, was obtained and on the basis of spectral analyses, chemical methods and enzymatic degradation its structure was establish...

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The Research of Land dynamic monitoring system in XiShan city

The Research of Land dynamic monitoring system in XiShan cit...

引用

International Conference on Info-Tech and Info-Net (ICII 2001)

作者： Dai, JF Zhang, Y CAS Nanjing Inst Geog & Limnol Nanjing 210008 Peoples R China

ISBN: (纸本)7900081585

Xishan city lies in the central part of Yangzi Delta, which is the one of the most wealthy regions in China. With the rapid development of economics, the population of the city is increasing constantly while the land area is decreasing. The contradiction between the increasing demand for land resources and the limited amount of land resources become apparent, which inhibits the rapid and steady development of economics. By applying RS and GIS technology and instituting land dynamic monitoring system, we can acquire the dynamic data and distribution of land, which have important meaning for the planning and decision of the city's national economics. This paper is emphasized on the planning of the system, the characters, the function and realization of the system.

关键词： land dynamic monitoring system

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Structure of 6-Epiforsticine and Revision of the Stereochemistry of Forsticine

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Chinese Chemical Letters 2000年第11期11卷 1003-1004页

作者： Wang, FP Li, ZB Chen, JJ Yang, JS W China Univ Med sci Sch Pharm Dept Chem Med Nat Prod Chengdu 610041 Peoples R China Chinese Acad sci Kunming Inst Bot Kunming 650204 Peoples R China

A norditerpenoid alkaloid, 6-epiforsticine, has been isolated from the roots of the plants. Aconitum hemsleyanum var. pengzhouense and A. kuzsnezoffii and its structure has been established as 1 on the basis of 2D-NMR... 详细信息

关键词： Structure of 6-Epiforsticine and Revision of the Stereochemistry of Forsticine

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