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Chinese Chemical Letters 1999年第5期10卷 379-382页

作者： Fend Pane WANG Ju Zheng FAN Xi Xian JIAN Bo Gang LI(Department of Chemistry of Medicinal Natural Products. School of Pharmacy. West China University of Medical sciences. chengdu 61004. {2. {3. of biology. CHinese {5. of sciences. {2. Dept. of Chem. of Med. Nat. Products School of Pharmacy W. China Univ. of Medical Sciences Chengdu 610041 China chengdu institute of {2. Chinese Academy of Sciences Chengdu 610041 China

Preparation of both 7. 17-seco yunnaconitine derivatives 6 starting from yunnaconitine 3.ia rearrangement of choroamine 5.is described.

关键词： Norditerpenoid Alkaloids 7. 17-seco ynnaconitine

Susceptibility Assessment of Landslides Caused by the Wenchuan Earthquake Using a Logistic Regression Model

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Journal of Mountain Science 2010年第3期7卷 234-245页

作者： SU Fenghuan Key Laboratory of Mountain Hazards and Land Surface Processes Chinese Academy of Sciences Chengdu China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Graduate University of the Chinese academy of sciences Beijing China

The Wenchuan earthquake on May 12.2.08 caused numerous collapses,landslides,barrier lakes,and debris *** susceptibility mapping is important for evaluation of environmental capacity and also as a guide for post-earthquake *** this paper,a logistic regression model was developed within the framework of GIS to map landslide *** County,a heavily affected area,was selected for the *** of landslides was prepared by interpretation of multi-temporal and multi-resolution remote sensing images(ADS40 aerial imagery,SPOT5.imagery and TM imagery,etc.) and field *** Certainly Factor method was used to find the influencial factors,indicating that lithologic groups,distance from major faults,slope angle,profile curvature,and altitude are the dominant factors influencing *** weight of each factor was determined using a binomial logistic regression *** susceptibility mapping was based on spatial overlay analysis and divided into five *** faults have the most significant impact,and landslides will occur most likely in areas near the *** of the area has a high or very high susceptibility,located in the northeast,south and southwest,including 65.3. of all landslides coincident with the *** susceptibility map can reveal the likelihood of future failures,and it will be useful for planners during the rebuilding process and for future zoning issues.

关键词： Landslide susceptibility WenchuanEarthquake GIS logistic regression certainty factor

Zircon SHRIMP U-Pb dating for the Cangshuipu volcanic rocks and its implications for the lower boundary age of the Nanhua strata in South China

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Science Bulletin 2003年第16期48卷 1663-1669页

作者： WANG Jian1, LI Xianhua2. DUAN Taizhong3. LIU Dunyi4, SONG Biao4, LI Zhongxiong1 & GAO Yonghua5.1. chengdu {2. of Geology and Mineral Resources, China Geologi-cal Survey, chengdu 610082. China 2. Guangzhou {2. of Geochemistry, Chinese academy of {5., Guangzhou 5.0640, China 3. Colorado School of Mines, Golden, CO 80401-1887, USA (Present address: Marathon Oil Company, Houston, TX 7705.-2.2.0} USA) 4. {2. of Geology, Chinese academy of Geological {5., Bei-jing 10003., China 5. Graduate School of the Chinese academy of Geological {5., Beijing 10003., China Correspondence should be addressed to Wang Jian (e-mail: jianwang@ ***) chengdu institute of Geology and Mineral Resources China Geological Survey Chengdu 610082 China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Colorado School of Mines Golden CO 80401-1887 USA institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China Graduate School of the Chinese academy of Geological sciences Beijing 100037 China

The continental volcanic rocks and volcaniclas-tic sedimentary conglomerates of the Cangshuipu Formation occur well in Yiyang of Hunan Province, consisting of a wedge-shaped succession of Neoproterozoic strata that over-lie with high-angle unconformity the flysch turbidites of the Lengjiaxi Group in the Upper Mesoproterozoic Eonothem. SHRIMP zircon U-Pb dating gives a weighted mean age of 814 12.Ma for the dacitic volcanic agglomerates from the lowest part of the volcanic rocks in the Cangshuipu Forma-tion. This age is younger than previously reported values of 92.—93. Ma for the volcanic rocks from the Cangshuipu Formation. Our new dating represents the lower boundary age of the Neoproterozoic System in the studied area. The younger age for the Cangshuipu volcanic rocks is supported by the following observations: （1） Lower Neoproterozoic strata （814—1000 Ma） are missing in the studied area; （2. the Nanhua rift system was initiated at about 82. Ma; and （3. an age of82. Ma may be taken as the lower boundary tim-ing of the Nanhua System （even Neoproterozoic） in South China.

关键词： Zicon U-Pb dating Neoproterozoic volcanics rift basin Nanhua System.

SYNTHESIS OF SOAP-FREE ACRYLIC HYDROSOLS

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Chinese Journal of Polymer Science 2002年第6期20卷 531-536页

作者： Li Jia Zong-hui Liu De-qing Wei Chengd institute of Organic Chemistry Chinese academy of {2.,{3., China Chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

Poly(methyl methacrylate/ethyl acrylate/acrylic acid) hydrosols were prepared by employing soap-free polymerization, and (acrylic acid/butyl acrylate) oligomer was used as the polymeric surfactant. The effect of reaction condition on the morphology and particle size of the hydrosols was investigated. The minimum amount of acrylic acid in the hydrosols is 2.. The maximum weight average molecular weight (M-w) of polymer that assures soap-free emulsion conversion into hydrosol is about 1.2.x 10(5.-1.3.x 10(5.. The particle transforming process was investigated, and an obvious change of particle diameter and morphology was observed.

关键词： hydrosol acrylic resin water-borne resin soap-free polymerization

Study of Catalysts on the Synthesis of Methyl Acrylate by Hydroesterification of Methyl Formate with Acetylene

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Chinese Chemical Letters 2000年第6期11卷 521-524页

作者： Xin Han HUANG Xian Gui YANG Jia Qi ZHANG Zhao Tie LIU(chengdu institute of Organic Chemistry, Chinese {2. of {3., chengdu 61004.) Chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

The catalytic hydroesterification of methyl formate (MF) with acetylene to methyl acrylate (MA) over nickel-based catalysts prepared by impregnation has been comprehensively studied in a fixed bed reactor at 160 similar to 2.0 degrees C and under 4 similar to 6MPa GHSV: 63.h(-1), CO:N-2.C2.2.= 65.2.:7. In present work, we have found a catalyst of 11wt%NiO/Al2.3.(80 similar to 100 mesh) prepared by wet impregnation with NiCl2.aqueous solution, then calcined in air at 5.0 degrees C for 5.h. The selectivity to methyl acrylate and the conversion of methyl formate over 11wt%NiO/Al2.3.catalyst are higher than other catalysts studied in this paper. The optimum reaction temperature for the hydroesterification of methyl formate with acetylene to methyl acrylate is around 2.0 degrees C.

关键词： Ni-based catalyst methyl formate methyl acrylate acetylene

Stereoselective Synthesis of (Z)-2.Acylamido-4-phenylcrotonates

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Chinese Chemical Letters 2000年第7期11卷 567-570页

作者： Yi Nong XIE Fan Min FU Ai Qiao MI Yao Zhong JIANG(chengdu institute of Organic Chemistry, Chinese {2. of {3.,chengdu {5.) Chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

Two practical methods for highly stereoselective synthesis of (Z)-2.acylamido-4-phenylcrotonates 2. similar to b have been developed. The key step in the first route was how to control the acid-catalyzed isomerization of condensation mixtures of alpha-keto ester 5.with carbomite. In the second route the key step was reduction of oxime 8, derived from alpha-keto ester 5. with iron powder in the presence of acetic anhydride.

关键词： (Z)-alpha,beta-dehydroamino acids stereoselective synthesis E -> Z isomerization Fe/Ac2. reduction of oxime

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 {2. and Natural Resources Re-search, Chinese academy of {2., Beijing 100101, China 2. institute of Forestry, Chinese academy of Forestry {2., Beijing 100091, China 3. Department of Civil Engineering, University of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese academy of {2., Beijing 100085. China 5. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, China 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 5.0 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 D5. (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 (D5., 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/km{3. 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.

Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China Earth sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2. JI Junfeg3. WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5.& LI Zhen6 1. SKLLQG, institute of Earth Environment, Chinese {2. of sciences, Xi’an 710075. China 2. Department of Urban and Resources sciences, Nanjing University, Nanjing 2.0093. China 3. Department of Earth sciences, Nanjing University, Nanjing 2.0093. China 4. Department of Geography, Shaanxi Normal University, Xi’an 710062. China 5. institute of Geology and Geophysics, Chinese {2. of sciences, Beijing 10002., China 6 Department of Geography, Qinghai Normal University, Xining 810008, China 7. Graduate School of the Chinese {2. of sciences, Beijing 10003., China 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate School of the Chinese academy of sciences Beijing 100039 China 2. Department of Urban and Resources sciences Nanjing University Nanjing 210093 China 3. Department of Earth sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2.0}visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63.μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63.μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

In flight MTF monitoring and compensation for CCD camera on CBERS-02

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Science China(Technological sciences) 2005年第S2期48卷 29-43页

作者： GU Xingfa1,2.3. LI Xiaoying1,2.4, MIN Xiangjun5. YU Tao1,2. SUN Jijuan5. ZENG Yong1,2.4, XU Hua1,2.& GUO Ding2.6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the {2. of Remote Sensing Applications of Chinese academy of sciences and Beijing Normal University, Beijing 100101, China 2. The Center for National Spaceborne Demonstration, Beijing 100101, China 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. Graduate University of Chinese academy of sciences, Beijing 10003., China 5. China Center for Resource Satellite Data and Application, Beijing 10083., China 6. University of Electronic Science and Technology of China, {5. 61005., China State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University 100101 Beijing China The Center for National Spaceborne Demonstration 100101 Beijing China Institut National de la Recherche Agronomique Climat Sol Environnement 84914 Avignon France Graduate University of Chinese academy of sciences 100039 Beijing China China Center for Resource Satellite Data and Application 100830 Beijing China University of Electronic Science and Technology of China 610054 Chengdu China

In this article, the approach of simulating ideal tarp scene was proposed to determine the MTF for CCD camera on CBERS-02. The MTF acquired from this technique was compared to those from some common methods. MTFs achieved from different approaches were employed to compensate the CCD images based on three restoration algorithms: the iterative method, the Wiener filter and the modified inverse filter (MIF). The two-dimensional MTF was established with the value at frequency 0.5.for 45. directional MTF as the value at its four corners. This article addressed the variations of the restored CCD images with different techniques of constructing two-dimensional MTF, restoring algorithms and determining the in-flight MTFs. Results showed images restored with the MTF determined from the technique of simulating ideal tarp scene represent the real scene best. And the restoration technique based on the MIF would produce better restored images than the other two techniques. This research also demonstrated that the two-dimensional MTF used for restoration should be interpolated under the control of the MTF for 45. axis, rather than by multiplying the cross-orbit MTF with along-orbit MTF.

关键词： CBERS-02 CCD MTF the technique of simulating ideal tarp scene.

The Effect of Al^(3.), Na^+, NH_4^+ on Ti Content in the Preparation of Ti-ZSM-5

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Chinese Chemical Letters 1999年第8期10卷 713-716页

作者： Cheng Hua XU Shao Jie LU Gui Ying DENG Fa Li QIU (chengdu institute of Organic Chemistry. Chinese {2. of {3., chengdu 61004.) Chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

The effect of Al3., NH, Na+ on the Ti content in the preparation of Ti-ZSM-5.by the isomorphous substitution of ZSM-5.using gaseous TiCl4 as titanium resource has been investigated. It is surprisingly found that although the direct ratio exists between the Ti content and the content of the skeletal Al: y=0.08x2.0.5.x+1.2.(here y represents TiO2. and x represents Al2.3.). but the catalytic activities of Ti-ZSM-5.for the oxidation of styrene sharply rise with the decrease of TiO2.. The skeletal Al hinders the Ti incorporation into the framework of molecular sieves characterized by FT-IR technique. At the same . NH ion has no effect on the Ti incorporation. but Na+ ion does.

关键词： Ti-ZSM-5 Ti content styrene catalytic oxidation