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Muricatenol, a Linear Acetogenin from Annona muricata (Annonaceae)

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chinese Chemical Letters 2000年第3期11卷 239-242页

作者： De Yu LI Jing Guang YU Xiu Zhen LUO Lan SUN Shi Lin YANG (Institute of Medicinal Plant Development. chinese academy of Medical {2. and Peking Union Medical College. {3. 100094) Inst. of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100094 China

Muricatenol 1, a new acetogenin, has been isolated from the seeds of Annona muricata L.. Compound 1 is a C-3. acetogenin without any THF rings. with four hydroxyls and one double bond in the long aliphatic chain. The hydroxyls of 1 are located at C-4, C-10, C-18 and C-19. respectively. The vicinal diet at C-18/C-19 is threo-configuration, and the double bond at C-14/C-15 is cis-configuration.

关键词： Annona muricata Annonaceae acetogenins muricatenol

Disuccinimidyl suberate cross-linked hemoglobin as a novel red blood cell substitute

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Science china(Life sciences) 2005年第1期48卷 49-60页

作者： LU Xiuling, ZHENG Chunyang, XU Yuhong & SU Zhiguo National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, chinese academy of {2., {3. 100080, china school of Life Science and Technology, {3. University of Chemical Technology, {3. 10002., china National Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing100080 China school of Life Science and Technology Beijing University of Chemical Technology Beijing100029 China

Disuccinimidyl suberate (DSS) intramolecularly cross-linked hemoglobin (Hb) was developed as a novel red blood cell substitute. A multi-angle laser light scattering detector coupled with size exclusion HPLC was applied to determine the molecular weight of the modified Hb. SDS-PAGE was also used as a complement. It was proved that 83.8% of the product was intramolecularly cross-linked Hb with weight-average molecular weights (Mw) of 67.5 kD, 12. was dimeric Hb with Mw of 146.6 kD, and 4.2. was trimeric Hb with Mw of 3.6.4 kD. The tetramer structure of the cross-linked Hb was stable as shown in size-exclusion chromatography using a mobile phase containing 1 mol/L MgCI2. Analysis by LC-MS demonstrated that the reaction of DSS with Hb mainly took place between the two a subunits within a Hb molecule, resulting in stabilization of the tetramer structure. However, the cross-linking was not site-specific. The P50 of the cross-linked Hb decreased from 2..8 mmHg to 14.3.mmHg, and the Hill coefficient decreased from 2.2. to 1.41. Result of isoelectric focusing showed that the pi of DSS cross-linked Hb was in the range of 4.6-5.2. similar to that of serum albumin. The safety of DSS cross-linked Hb was favored by animal tests on rats and guinea pigs. Exchange transfusion experiment with DSS cross-linked Hb using rats as a model indicated no pressor effect or other significant side effects. The characteristics and properties of DSS cross-linked Hb were also compared with that of diaspirin cross-linked Hb reported in the literature.

关键词： hemoglobin, disuccinimidyl suberate, cross-link, red blood cell substitute.

THE STUDIES ON THE SEPARATION AND IDENTIFICATION OF EPHEDRINES IN URINE BY GC/MSD

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chinese Chemical Letters 1990年第1期1卷 75-78页

作者： Jian Fang CUI Lin LI Tong Hui ZHOU(Institute of Materia Medica,chinese academy of Medical {2.,{3. 100050)

The separation and identification of the ephedrines(cathine,norephe-drine,ephedrine,pseudoephedrine,methylephedrine and ethylephedrine)and their derivatives obtained from TFAA,MSTFA,MSTFA+MBTFA and MSTFA+Ethyl acetate... 详细信息

关键词： THE STUDIES ON THE SEPARATION AND IDENTIFICATION OF EPHEDRINES IN URINE BY GC/MSD TFA TMS GC

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生物质燃气催化重整净化的特性研究

太阳能学报 2006年第7期27卷 666-670页

作者：崔小勤常杰王铁军张琦付严张兴华中国科学院广州能源研究所

通过改变生物质燃气重整过程中重整温度、反应时间、水蒸气的添加等参数,考察了国产烃类蒸汽转化催化剂Z405重整净化生物质燃气的性能及对合成气化学当量比的调变作用。结果表明:在Z405的作用下,生物质燃气中CH4和C2.化率均高达95%以上... 详细信息

通过改变生物质燃气重整过程中重整温度、反应时间、水蒸气的添加等参数,考察了国产烃类蒸汽转化催化剂Z405重整净化生物质燃气的性能及对合成气化学当量比的调变作用。结果表明:在Z405的作用下,生物质燃气中CH4和C2.化率均高达95%以上,合成气中CH4和C2.含量分别低于0.500%和0.005%,H2.CO含量有显著增加,CO2.量有所减少。添加水蒸气后H2.CO值较之无水蒸气的添加发生了显著变化,从0.70提高到1.15,气体低热值有所增大。提高重整温度对生物质合成气组分具有显著的调变作用,H2.CO含量增幅随温度升高而增加,CH4与C2.分含量降低幅度也随温度升高而增加。但当重整温度超过780℃时,对合成气组分调整作用不明显。重整生物质燃气组分在60min内无明显改变,未检测到催化剂活性降低、失重及积炭。

关键词：烃类蒸汽转化催化剂生物质燃气重整反应

Electroporation of Mouse Retinal Ganglion Cells

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Electroporation of Mouse Retinal Ganglion Cells

CO_2.efflux from different forest soils and impact factors in Dinghu Mountain, china

中国神经科学学会第四次会员代表大会暨第七届全国学术会议

作者： Qiang ZENG,Shi-Gang HE Institute of Biophysics,chinese academy of {2.,{3.,china

＜正＞Purpose The electroporation of mouse retinal ganglion cells（RGCs） is not efficient after birth,as transfection of the differentiated neurons is much difficult than the newly born cells or the *** this study,the electroporation of mouse embryo retina is used to transfect the RGCs when they are *** The E13.E14 embryo mouse retinae are isolated and electroporated in vitro and then were cultured for a few days to record the development of RGCs. The morphology of the RGCs is showed by GFP expression after *** RGCs are identified by anti-Brn3. *** candidate genes involved in the dendritic development are also expressed by electroporation. Results The primary study shows that the electroporation of embryo mouse retina could transfect many cells and show their *** distribution of GFP positive cells is uniform in the *** in vitro culture system could support the retina for at least 4 d,which permits the imaging of the development *** Electroporation of RGCs provides a powerful tool for analyzing the dendritic development and the candidate genes *** dendrite morphology imaging and gene expression control are combined together,which makes it an efficient *** the in vivo electroporation is achieved in further study,the RGCs electroporation could be used for long-term study of dendrite development.

关键词： electroporation retinal ganglion cell mouse GFP

来源： cnki会议评论

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cnki会议

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Science china Earth sciences 2005年第Z1期48卷 198-206页

作者： ZHOU Cunyu, ZHOU Guoyi, ZHANG Deqiang, WANG Yinghong & LIU Shizhong Dinghushan Forest Ecosystem Research Station, chinese academy of {2., Guangzhou 510650,{3. Institute of Atmospheric Physics, chinese academy of {2., beijing 10002.,{3. Dinghushan Forest Ecosystem Research Station Chinese Academy of Sciences Guangzhou 510650 China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

CO2.fluxes from soils and related environmental factors were measured in three forest ecosystems of Dinghu Mountain using static chamber-gas chromatograph technique for one year. The seasonal pattern of CO2.flux, contribution of litter on total CO2.flux and the correlations of CO2.flux with soil temperature and soil water content were examined for each type of forest. The results were given as followings: (1) The seasonal patterns of CO2.flux from soil of the three types of forest were similar, with a higher CO2.flux in rainy season than in dry season. The comparative relations of mean annual CO2.fluxes between the three sites were expressed as:monsoon forest ＞ mixed forest ＞ pine forest. (2. CO2.fluxes from litter decomposition in monsoon forest, mixed forest and pine forest accounted for 2..43., 41.75% and 2..2.% of the corresponding total CO2.fluxes from forest floor, respectively. (3. Significant relationships were found between CO2.fluxes and soil temperatures at 5 cm depth for the three types of forest, which could be best described by exponential equations. The calculated Q10 values based on soil temperature at 5 cm depth ranged from 1.86 to 3.2.. More significant relationships were found between CO2.fluxes and soil water content when the annual variation coefficients of soil moisture were higher.

关键词： CO2 flux, litter decomposition, Q10, soil moisture.

Ternary geochemical-tracing system in natural gas accumulation

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Science china Earth sciences 2007年第10期50卷 1494-1503页

作者： LIU WenHui1,2., CHEN MengJin3. GUAN Ping4, ZHENG JianJing2. JIN Qiang5, LI Jian6, WANG WanChun2. HU GuoYi3. XIA YanQing2.& ZHANG DianWei2.1 Exploration & Production Research Institute, SINOPEC, beijing 100083. china 2.Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, {2. academy of sciences, Lanzhou 73.000, china 3.Research Institute of Petroleum Exploration & Production, Petrochina, beijing 100083. china 4 school of Earth and Space sciences, Peking University, beijing 100871, china 5 china University of Petroleum (East china), Dongying 2.7062.,china 6 Longfang Branch, Research Institute of Petroleum Exploration & Production, Petrochina, Longfang 065007, china Exploration & Production Research Institute SINOPEC Beijing 100083 China Research Institute of Petroleum Exploration & Production PetroChina Beijing 100083 China school of Earth and Space sciences Peking University Beijing 100871 China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China china University of Petroleum (East china) Dongying 257062 China Longfang Branch Research Institute of Petroleum Exploration & Production PetroChina Longfang 065007 China

The establishment of geochemical-tracing system of gas generation and accumulation is helpful to re-elucidating the gas migration and accumulation in time and space. To deduce the complex process of gas accumulation, a ternary geochemical-tracing system is set up, according to stable isotope inheritance of source rocks, kinetic fractionation of stable isotopes, time-accumulating effect of noble gas isotopes, mantle-derived volatile inheritance, and organic molecule inheritance of light hydrocarbons and thermally kinetic fractionation in their generation, in combination with the previous achievements of gas geochemistry and geochemical parameters of gas-source correlation. There are tight interactions for the geochemical parameters with much information about parent inheritance and special biomarkers, in which they are confirmed each other, reciprocally associated and preferentially used for the requirement so that we can use these geochemical parameters to effectively demonstrate the sources of natural gas, sedimentary environments and thermal evolution of source rocks, migration and accumulation of natural gas, and rearrangement of natural gas reservoirs. It is necessary for the ternary geochemical-tracing system to predict the formation of high efficient gas reservoir and their distribution in time and space.

关键词： stable isotope, noble gas, light hydrocarbon, tracing system, sources of natural gas

Investigation on composite Au/TiO_2.nanoparticles (Ⅰ)——Synthesis and characterization

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chinese Science Bulletin 1998年第3期43卷 210-213页

作者： WANG Chuanyi, LIU Chunyan and SHEN Tao Institute of Photographic Chemistry, chinese academy of {2., {3. 100101, china

Nanometer sized Au/TiO\-2.particles were synthesized by irradiation of a HAuCl\-4 solution containing colloidal TiO\-2.with light of wavelength (λ)>3.0 nm. The absorption maximum attributed to the surface plasmon band of gold was observed at 540 nm, a red shift of about 2. nm from the position in aqueous solution. The Au clusters are situated on the surface of TiO\-2.in terms of microcrystallite, which was confirmed by HRTEM, EDS and XRD. The electronic interfaction between the metal and the suport was discussed.

关键词： photocatalytic reduction composite Au/TiO\-2 nanoparticles surface plasmon band.

Sequence Stratigraphy and Tectonic Environment of the Chartai Group,Inner Mongolia

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 217-235,341-342页

作者： Qiao Xiufu Yao Peiyi Wang Chengshu Tan Lin Zhu Shenyu Zhou Shengde Zhang Yuqing Institute of Geology,chinese academy of Geological {2., {3. Regional Geological Survey Party,Geological Bureau of Inner Mongolia,Hohhot Sun Sheping Institute of Geology Chinese Academy of Geological Sciences Beijing China

The Middle Proterozoic Chartai Group separated by two unconformities consists of three depositional se-quences: the Shujigou Formation-Zenglongchang Formation (DS Ⅰ), the Agulugou Formation (DS Ⅱ), andthe Liuhongwan Formation (DS Ⅲ). The carbonate platform and back-platform basin are the basic environ-ment model of the Chartai Group. The syndepositional faults on the oceanward side of the carbonate platformand large-scale slumping in the soft sediments are important marks of facies tracts. The newly establishedZenglongchan uplifting, an epeirogenetic uplifting, plays an important role in the formation of thepalaeogeographic framework of the Chartai Group. The stratigraphic correlation between the Chartai Groupand the Bayan Obo Group is made for the first time by using sequence stratigraphic principle and model estab-lished by P.R. Vail. The Chartai Group, which was deposited on the northern passive continental margin of theNorth china platfom, represents the platform cover.

关键词： Sequence Stratigraphy and Tectonic Environment of the Chartai Group Inner Mongolia