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101.
A Study of the Probe Effect on the Apparent Image of Biological Atomic Force Microscopy 总被引:1,自引:0,他引:1
Xue Mei WANG * Lei QIN Long BA Zu Hong LU The State Key Lab of Coordination Chemistry Nanjing University Nanjing National Lab of Molecular Biomolecular Electronics Southeast University Nanjing 《中国化学快报》2001,(12)
The atomic force microscopy (AFM) possesses high spatial resolution and it is compatible with liquid environments. AFM can provide possibility to study a wide range of biological problems at the molecular level and acquire topological information at nanometre resolution under physiological conditions1,2. However, a major problem for image reconstruction of biological specimens is that structures of most biological molecules are very soft and delicate, which could be easily deformed and dama… 相似文献
102.
A new and simple capillary electrophoresis with electrochemiluminescence detection was developed for the separation and the quantification of a pair of diastereoisomenc alkaloids(ephedrine and pseudoephedrine).The limits of detection(S/N = 3) were 4.5×10-8 mol/L for ephedrine and 5.2×10-8 mol/L for pseudoephedrine,respectively.The RSDs of migration time and peak area were less than 1.3 and 2.5%(n = 5),respectively.The applicability of the propose method was illustrated in the determination of ephedrine and pseudoephedrine in human urine,ephedrine in nasal drops,and the monitoring of pharmacokinetics for pseudoephedrine. 相似文献
103.
GU Xin-quan CHEN Yan-ping HU Ting-ting LU Xiu-hua LI Xi-qian DU Xiao-hui CAO Xia WANG Wei-hua XU Zhong-gao .China-Japan Union Hospital of Jilin University Changchun P.R.China .College of Chemistry Jilin University Changchun .College of Pharmacy Changchun 《高等学校化学研究》2011,(4):584-588
This paper studies the extraction and identification of ginsenoside Re from ginseng fruits and investigates the effect and mechanism of ginsenoside Re of protecting acute renal ischemia-reperfusion injury in rats.Having been smashed,the ginseng fruits were ultrasonically extracted twice with 95% ethanol for 30min each.Having been concentrated,the solution was dissolved with distilled water and separated by two-column chromatography,of which one was packed with macroporous resin D4020,and the other was packe... 相似文献
104.
CHEN WenWen LI TangSong HE Sha LIU DingBin WANG Zhuo ZHANG Wei & JIANG XingYu CAS Key Laboratory for Biological Effects of Nanomaterials Nanosafety National Center for Nanoscience Technology Beijing China Graduate Schoold of the Chinese Academy of Sciences Beijing China Key Laboratory of Microsystems Microstructures Manufacturing Ministry of Education Harbin Institute of Technology Harbin College of Bioengineering Chongqing Universit... 《中国科学B辑(英文版)》2011,(8)
Immunoassays are useful for many bioassays. Many new techniques and materials are introduced into the immunoassay to improve the efficiency. This paper reviews recent progress in the application of microfluidic systems and gold nanoparticles in immunoassay. The micro/nano technologies and materials can offer good sensitivity, fast detection, cost-effectiveness and easy signal readout. In particular, the miniaturization of microfluidics and colorimetric assays based on gold nanoparticles have dramatically im... 相似文献
105.
WEI Wei LI Xu-wen SHI Xiao-lei ZHOU Hong-yu YANG Rui-jie ZHANG Han-qi JIN Yong-ri College of Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2011,27(1):23-27
Matrix solid-phase dispersion(MSPD) was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots of Aconitum kusnezoffii Reichb. The determination of the analyte was carried out by high performance liquid chromatography with UV detection. The alkaline alumina was used as sorbent. The mixture of acetonitrile and water was used as elution solvent. Several extraction parameters, such as type of sorbent, the ratio of sample to solid suppo... 相似文献
106.
107.
Preparing Nano-ZnS by Solid State Reaction at Room Temperature 总被引:3,自引:0,他引:3
Xiao Lin SUN Guang Yan HONG* Laboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Changchun 《中国化学快报》2001,(2)
Solid-state reaction has been studied for a long time1-3. In recent years, some researches have been focused on the preparation of coordination compounds at low temperatures or even at room temperature4-5. In this letter, preparation of ZnS nanoparticles by using solid state reaction at room temperature is reported.ZnS nanoparticles were prepared as follows: Zn(CH3COO)2 and Na2S?9H2O, in equal molar ratio, were ground in agate mortar. After 20 minutes, the powder was washed by water and … 相似文献
108.
Guang Xing WANG Jing Xin ZHANG Shu Feng CHEN Xiao Tian LIANG* Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 《中国化学快报》2001,(3)
Chrysotricine 1 was isolated from the Chinese herb medicine Hedyotis Chrysotricha and was shown to possess antitumor activity1. Its structure has been elucidated as a novel zwitterionic (-carboline alkaloid containing a 2,2,5-trisubstituted tetrahydrofuranyl group. The (-carboline compounds have attracted considerable attraction in recent years because of their promising and intriguing biological activities2. Recently, we have established the absolute configuration of chrysotricine by the fir… 相似文献
109.
Wei Min WANG Xin Miao LIANG* Qing ZHANG Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 《中国化学快报》2001,(3)
Recent legislation in many countries requires extensive testing of all manufactured chemicals for environmental evaluation and registration. Among the requirements are water solubility, solvent (usually octanol) - water partition coefficient, soil adsorption and bioconcentration factors in aquatic organisms. Soil adsorption influences the extent of vaporization of a compound from the soil surface and its lateral (run-off) or vertical transport including groundwater contamination. Additionally,… 相似文献
110.
Cheng Feng YE Ze Fu ZHANG Wei Min LIU* State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 《中国化学快报》2001,(4)
In recent years, many efforts were focused on the preparation and characterization of phosphazene which contained a framework of alternating phosphorous and nitrogen atoms with two substituent groups attached to each phosphorous atom1. It is noticeable that cyclophosphazene, especially hexaaryloxyphosphazene and perfluoroaryloxyphosphazene exhibit excellent thermal and chemical stability which can be used as fireproof materials, high temperature lubricants, vacuum pump oils and hard disk surfac… 相似文献