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101.
本文介绍了一种分析裂化气中杂质烃的方法。所建分析系统由填充玻璃毛细管柱和填充预柱各一根、阀和FID各一个组成。采用一次进样、外标法定量,约30分钟即可完成测定裂化气中低至0.5ppm含量的痕量C_2~C_4炔和二烯。方法适用围范至少是0.5ppm~1%。当样品含量为1~5 ppm时,相对标准偏差小于50%。 相似文献
102.
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
103.
Li Yuan MOU Zi Yun LIN Li Ya ZHU* Xiao Tian LIANG Institute of Materia Medica Chinese Academy of Medical Sciencesand Peking Union Medical College Beijing Center for Biophysical Science Engineering University of Alabama at Birmingham 《中国化学快报》2001,(6)
Mannich reaction is widely used for the synthesis of many kinds of compounds1. In the synthesis of the derivatives of styryl ketonic Mannich bases, a one-pot method is used, in which ketone, secondary-amine hydrochloride, paraformaldehyde are refluxed together in alcohol2,3. In most cases the normal Mannich product MA is obtained. But when certain amine is used as the reactant, a side-product IM, instead of MA is obtained. MS and 1HNMR data indicate that compound IM is a new type of Man… 相似文献
104.
Neng Dong WANG Liu Min CHEN Sheng JIN= Xiu ZHANG Jia Hua CHEN* The Key Lab of Bioorganic Chemistry Molecular Engineering Ministry of Education China College of Chemistry Molecular Engineering Peking University Beijing 《中国化学快报》2001,(10)
The drug overdose and addiction is a serious international problem. Therefore developing a rapid, accurate, convenient and cheap method for detecting morphine in urea is useful and necessary, especially for investigation of epidemiology, identification of medical jurisprudence and determination of drug addict etc. There are many compounds that are similar to morphine in chemical structure and tend to have cross-reaction with the anti-morphine antibody. In order to reduce the cross reaction a… 相似文献
105.
106.
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
107.
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
108.
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
109.
LIU ChengHui WANG Zhe WANG XiaoKe & LI ZhengPing Key Laboratory of Medicinal Chemistry Molecular Diagnosis Ministry of Education College of Chemistry Environmental Science Hebei University Baoding China 《中国科学B辑(英文版)》2011,(8)
β-NaYF4:Yb,Er upconversion nanophosphor (UCNP) is known as one of the most efficient NIR-to-visible upconversion materials, which shows great potential in bioanalytical chemistry and bioimaging. However, its applications are greatly limited due to its low water dispersibility and thus poor biocompatibility. In this paper, poly(acrylic acid) (PAA)-based ligand exchange strategies are carried out to modify oleic acid-capped hydrophobic β-NaYF4:Yb,Er UCNPs into hydrophilic ones. After efficient surface modific... 相似文献
110.