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Science china Chemistry 2010年第4期53卷 826-831页

作者： KONG LinLin, KAN MeiXiu, HAN DongMei, WANG Ting & ZHANG HuiMin School of Science, beijing institute of Technology, beijing 100081,{3. 1. School of Science Beijing Institute of Technology Beijing 100081 China

A new approach for the highly sensitive detection of dopamine by a novel composite film involving gold nanoparticles trapped in a negatively-charged fluorocarbon polymer (Nafion) on a glassy carbon (GC) electrode fabricated by a simple method is described. Gold nanoparticles with an average diameter of 2.3.nm ± 0.2 nm are dispersed throughout the whole Nafion film. The introduction of gold nanoparticles into the Nafion film not only gives a highly active electrode surface area but also increases the conductivity of the Nafion film and the resulting Au/Nafion/GC electrode combines the advantages of the properties of gold nanoparticles and the selective pre-concentration ability of Nafion. For positively charged dopamine, the results show a decrease in the redox peak separation and a high sensitivity. The oxidation peak current of dopamine was shown to vary linearly with dopamine concentration over a wide range from 0.4 to 50.0 μmol/L with a detection limit of 0.3.μmol/L. Negatively charged ascorbic acid shows no redox waves at concentrations up to 1.0 ×10-4 mol/L.

关键词： composite film gold nanoparticles Nafion dopamine ascorbic acid

ISOLATION AND STRUCTURE DETERMINATION OF XF-1,A NEW ANTHRACYCLINE ANTIBIOTIC

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chinese Chemical Letters 1993年第9期4卷 787-790页

作者： Xu Guang YAN Jian Bo WU a.institute of Medicinal Biotechnology,chinese academy of Medical {3.,beijing 100050Shao Zhao WANG b.institute of Microbiology,Fuzhou 3.0007

A new Mutactimycin group antibiotic(XF-1)was isolated from the mycelium of Streptomyces sp.80-115 and its structure has been determined on the basis of its spectroscopical and chemical properties. XF-1 showed active a... 详细信息

关键词： ISOLATION AND STRUCTURE DETERMINATION OF XF-1,A NEW ANTHRACYCLINE ANTIBIOTIC OH Figure

Characteristics and Warning Indexes of Rice Seeds Viability Loss During Storage at 45℃ Constant Temperature

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Agricultural sciences in china 2002年第8期1卷 911-915页

作者： LU Xin-xiong and CHEN Xiao-ling(Key Laboratory for Crop Germplasm and Biotechnology of Agricultural Ministry, institute of Crop Germplasm Resources, chinese academy of Agricultural {3., beijing 100081, P.R.china) Key Laboratory for Crop Germplasm and Biotechnology of Agricultural Ministry Institute of Crop Germplasm Resources Chinese Academy of Agricultural Sciences Beijing 100081 P.R. China

Seed aging characteristics of rice was investigated in this study. Seeds of 3. japonica rice (O-ryza sativa subsp. japonica) varieties were held at 451 constant temperature. Changes in seed viability and seed vigor during aging process were measured to study seed viability-losing characteristic and to determine warning index for seed viability loss. As a result, seed viability survival curves were obtained across different rice accessions at 45℃ constant temperature. The curves appeared to be contra-sigmoid survival curves. The loss of seed viability in the aging process consisted of two phases. The first phase took a long duration, in which the viability of vigorous seeds declined slowly. In the second phase, seed viability declined rapidly. It was obvious that seed viability declined inconsistently during storage. It also showed that seed germination was prolonged and the seedling was significantly weakened before the coming of the rapid declining phase of seed viability. These two parameters could be used to indicate seed quality during storage. The rate of compatibility of tests (RCT), coefficient of variation (CV), vigor of seedling, the day the seeds start to germinate could be used as warning indexes to indicate overall quality of a mass of accessions. These warning indexes could also be used in monitoring the viability of seeds stored in the seed genebank.

关键词： Seed viability-loss characteristics Warning indexes Seed viability monitoring Germplasm conservation

Fast calculate the parameters of surface acoustic wave coupling-of-modes model

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chinese Journal of Acoustics 2007年第3期26卷 269-277页

作者： LIU Jiansheng HE Shitang institute of Acoustics Chinese Academy of Sciences Beijing 100080 Graduate University of chinese academy of sciences beijing 100080

Accurate solutions of acoustic waves in piezoelectric substrate and metal film as layered structure were obtained. Phase velocity, electromechanical coupling coefficient and static capacitance were calculated based upon the solutions. Chen and Haus＇ theory was used to analyze surface acoustic waves in shorten gratings with single finger every period and a reflection coefficient expression of one strip was presented. Parameters of aluminum on X-112°Y LiTaO3.and gold on ST-quartz were calculated. The results agreed well with those from Ken-ya Hashimoto＇s theory. The reflection coefficient of gold on ST-quartz was measured to verify the theoretical result.

关键词： reflection coefficient surface acoustic waves coupling coefficient layered structure metal film

川西獐牙菜与抱茎獐牙菜中酮的高效液相色谱分析

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色谱 2004年第1期22卷 51-53页

作者：宋娅莉胡凤祖林鹏程卢永昌师治贤中国科学院西北高原生物研究所青海民族学院化学系青海西宁810007

采用反相高效液相色谱法同时分离和测定了龙胆科獐牙菜属的川西獐牙菜和抱茎獐牙菜中几种酮的含量。色谱柱为KromasilC18(250mm×4 60mmi d ,5μm),流动相为甲醇 0 1%的磷酸水溶液(体积比为73.27),流速1mL/min,检测波长260nm,柱温20... 详细信息

采用反相高效液相色谱法同时分离和测定了龙胆科獐牙菜属的川西獐牙菜和抱茎獐牙菜中几种酮的含量。色谱柱为KromasilC18(250mm×4 60mmi d ,5μm),流动相为甲醇 0 1%的磷酸水溶液(体积比为73.27),流速1mL/min,检测波长260nm,柱温20℃。实验结果表明,该方法具有很好的线性关系与精密度,方法简单、准确、实用性强。

关键词：中草药川西獐牙菜抱茎獐牙菜 San酮高效液相色谱分析分离含量测定

Landscape patterns and their evolutions in　the suburban ecotone──A case study of the eastern suburb of beijing

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Journal of Environmental sciences 1994年第3期6卷 277-286页

作者： Yang Jurong,Zhang Hongmei,Huang Yi institute of Environmental Science,beijing Normal University,beijing 100875,{3.

The characteristics and evolutions of the landscape patterns in the suburban ecotone are studied on the basis of landscape-ecological maps of different years derived from the corresponding aerial photos The relationship between landscape patterns and urban economical development is ana- lyzed. The diversity index is used to characterize the features of the landscape patterns in the ecotone and define the location of Sharp change.

关键词： suburban ecotone landscape patterns diversity index.

A Novel Method for Studying the interaction of Macromolecule with Small Molecule by Means of Affinity Capillary Electrophoresis

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chinese Chemical Letters 1999年第3期10卷 235-238页

作者： Met FANG Li SHENG Hut Wan HAN Xiao YU Rut ZHAO Guo Quan LIU(Laboratory of Analytical Chemistry in Life Science, institute of Chemistry, chinese academy of{3.，beijing 100080) chinese Acad Sci Inst Chem Lab Analyt Chem Life Sci Beijing 100080 Peoples R China

A novel capillary electrophoresis method coupled with on-line microdialysis using an attachable electrode has been developed to study the interaction of macromolecule with small molecule. The binding constants of bovine serum album (BSA) with D,L-tryptophan (Trp), sulfamethoxazole (SMZ) with trypsin and chymotrypsin were determined. These values are 2.3.x 10(4)L/mol for BSA-L-Trp; 1.77 x 10(3. L/mol for BSA-D-Trp in pH 7.4, 50 mmol/ L phosphate; 1.4 x 10(4) L/mol for SMZ- trypsin and 6.0 x 10(3. L/mol for SMZ-chymotrypsin in pH 6.5, 25 mmol/L Tris buffer. The proposed method has merits of speed, low sample consumption and readily available to be performed in desired physiological conditions.

关键词： interaction of macromolecule with small molecule binding constant affinity capillary electrophoresis microdialysis membrane

PALEOZOIC ACCRETIONARY AND COLLISIONAL TECTONICS OF THE EASTERN TIANSHAN(china):IMPLICATIONS FOR THE CONTINENTAL GROWTH OF CENTRAL ASIA

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PALEOZOIC ACCRETIONARY AND COLLISIONAL TECTONICS OF THE EAST...

STUDIES　ON　SEPARATION　AND　DETERMINATION　OF　THE　COUMARINS　IN　MURRAYA　PANICULATA（L）JACK　BY　RP－HPLC

中国科学院地质与地球物理研究所2004学术年会

作者： WEN-JIAO XIAO,LIAN-CHANG ZHANG,KE-ZHANG QIN,SHU SUN, and JI-LIANG LI Key Laboratory of Lithospheric Tectonic Evolution,institute of geology and geophysics,{3. academy of sciences,beijing 10002.,china

This paper deals with the various tectonic units in the chinese Eastern Tianshan orogenic collage in the Central Asian Orogenic Belt,and discusses the Paleozoic geological history of the several periods of accretion and collision of archipelago systems lying between the Tarim and southern Angaran continental *** Late Ordpvician-Silurian to Early Devonian Eastern Tianshan archipelago was characterized by(a) the Harlik-Dananhu subduction system with a S-dipping polarity in the north;(b) a southerly N-dipping subduction system beneath the Central Tianshan arc in the middle;and(c) the South Tianshan ocean against Tarim in the *** the Devonian to Early Carboniferous,N-dipping subduction led to the Harlik-Dananhu arc and the Kanggurtag forearc basin/accretionary *** the Early to Mid-Carboniferous,the magmatic front associated with the N-dipping subduction beneath the Dananhu-Harlik arc migrated southwards,forming the Yamansu arc constructed upon the Kanggurtag accretionary *** the Late Carboniferous the Dananhu-Harlik arc was attached northwards to the Angaran margin,resulting in lateral enlargement of the Angaran *** the latest Carboniferous to Early Permian a multiple soft collision left wide suture zones in the south that include the ophiolite-strewn Aqikkuduk-Shaquanzi and Kumishi accretion-collision complexes, which were stitched by Early Permian post-collisional *** re-defining and re-interpreting the various tectonic terranes,this paper presents a new,improved model for the Paleozoic evolution of this part of Central Asia.

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chinese Chemical Letters 1994年第4期5卷 313-314页

作者： HuI XU ZHi Hua ZHOU(institute of MatERLA materla , chinese Aeademy of Medieal sciences, {3. 100050)

A simple , sensitive and accurate RP-HPLC method for the separation and determintion of six eoumatins in M. paniculata (L) Jaek, was described The metnod has been .applied to the analysis of different samples.

关键词： HPLC RP AND

A New Oligostilbene from the Roots of Vitis Amurensis

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chinese Chemical Letters 1999年第9期10卷 775-776页

作者： Kai Sheng HUANG Mao LIN Lin Nine YU Man KONG(institute of Materia Mad ica. chinese academy of Medical {3.and Peking Union Medical College. beijing 10000) chinese Acad Med Sci Inst Materia Medica Beijing 100050 Peoples R China Peking Union Med Coll Beijing 100050 Peoples R China

A new resveratrol trimer. amurensin G (1), was isolated from the roots of Vitis amurensis Rupr. Its structure and relative configuration were established on the basis of spectral evidence. especially on HMBC spectrum ... 详细信息

关键词： Vitis amurensis Vitaceae oligostilbene amurensin G resveratrol