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121.
本文从细胞悬浮液制备、单个细胞进样技术、细胞溶解技术、分离模式、检测方法和应用新进展6个方面对单细胞毛细管电泳分析进行了全面评述.重点介绍了单个细胞进样技术及检测方法的最新进展,并对单细胞毛细管电泳分析的未来发展方向进行了展望. 相似文献
122.
七种花旗参茶包的FTIR光谱法无损鉴别 总被引:11,自引:2,他引:11
本文利用傅里叶变换红外光谱法(FTIR)无损快速鉴别了七种花旗参茶包。各种花旗参茶包的红外光谱较特征。根据红外的特征谱图分析,市售的7种花旗参茶包基本上可分为两大类,一类是纯的花旗参药材料末而制成的茶包;另一类是花旗参的提取物和辅料混合后而制成的茶包。红外光谱图还表明各种花旗参茶包所选用的辅料也不尽相同,有的采用葡萄糖,有的则采用蔗糖,辅料所添加的种类与有的商品标定的不符。另外花旗参茶包所添加的辅料较多,花旗参提取物的特征峰较弱,这就表明有的花旗参茶包的质量较差。HPLC的分析结果也证明了采用原药材而制成的花旗参茶包的总皂甙含量高于花旗参的提取物和辅料混合后而制成的茶包,基本上相差了4倍。因此,红外光谱法快速、直观、可靠,适用于中药的鉴定。 相似文献
123.
The covalent immobilization of trypsin onto poly[(methyl methacrylate)-co-(ethyl acrylate)-co-(acrylic acid)] latex particles, produced by a soap-free emulsion polymerization technique, was carried out using the carbodiimide method. The catalytic properties and kinetic parameters, as well as the stability of the immobilized enzyme were compared to those of the free enzyme. Results showed that the optimum temperature and pH for the immobilized trypsin in the hydrolysis of casein were 55 degrees C and 8.5, both of which were higher than that of the free form. It was found that K(m) (Michaelis constant) was 45.7 mg . ml(-1) and V(max) (maximal reaction rate) was 793.0 microg . min(-1) for immobilized trypsin, compared to a K(m) of 30.0 mg . ml(-1) and a V(max) of 5 467.5 microg . min(-1) for free trypsin. The immobilized trypsin exhibited much better thermal and chemical stabilities than its free counterpart and maintained over 63% of its initial activity after reusing ten times. 相似文献
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We examine the support for the Batchelor spectrum from well-resolved simulations of high-Schmidt-number mixing in isotropic turbulence, and resolve a conundrum with respect to the numerical value of the prefactor, also known as the Batchelor constant. Our conclusion is that the most probable value of the most compressive principal strain rate is more relevant than its mean, at least asymptotically. 相似文献
127.
A‐D‐A Type Small Molecules Based on Boron Dipyrromethene for Solution‐Processed Organic Solar Cells 下载免费PDF全文
Liangang Xiao Dr. Hongda Wang Ke Gao Dr. Lisheng Li Chang Liu Prof. Dr. Xiaobin Peng Prof. Dr. Wai‐Yeung Wong Prof. Dr. Wai‐Kwok Wong Dr. Xunjin Zhu 《化学:亚洲杂志》2015,10(7):1513-1518
The unique properties of boron dipyrromethene (BODIPY) dyes including facile synthesis, high absorption coefficients, and delocalized molecular orbitals as well as excellent photochemical and thermal stability, make them promising as materials for organic solar cells. Accordingly, in this study three A‐D ‐A structural small molecules of BDTT‐BODIPY, FL‐BODIPY, and TT‐BODIPY have been synthesized, in which two BODIPY acceptor units are symmetrically conjugated to 4,8‐bis(5‐(2‐ethylhexyl) thiophen‐2‐yl)benzo[1,2‐b:4,5‐b]dithiophene (BDTT), 9,9‐dioctyl‐9H‐fluorene (FL), and thieno[3,2‐b]thiophene (TT) donor cores, respectively. The manipulation of the structural parameters significantly improves the performances of the BHJ OSCs, which show power conversion efficiencies of 4.75 %, 1.51 %, and 1.67 % based on [6,6]‐phenyl C71‐butyric acid methyl ester (PC71BM) as the acceptor material and BDTT‐BODIPY, FL‐BODIPY, and TT‐BODIPY as the donor materials, respectively. 相似文献
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An HPLC method with a fluorescence detector (HPLC-FLD) was described for the quantitative determination of closantel and rafoxanide in bovine and ovine muscles. A structural analog closely related to rafoxanide, viz., N-[4-(4-chlorophenoxy)phenyl]-2-hydroxy-3,5-diiodobenzamide, was synthesized as an internal standard. Bovine and ovine muscles were extracted with acetonitrile-acetone (60 + 40, v/v) followed by cleanup on mixed mode anionic exchange SPE cartridges. After evaporation and reconstitution with the mobile phase, the sample was analyzed by HPLC-FLD using internal standard calibration. The method was validated by using fortified bovine and ovine muscles at 15, 30, and 60 microg/kg. The accuracy and RSD were 70-110% and < or =10%, respectively. 相似文献
130.
Jiangwei Li Wenjun Xie Ning Fang Edward S. Yeung 《Analytical and bioanalytical chemistry》2009,394(2):489-497
Ultrasensitive detection and quantification of viral antigen with a novel single-molecule immunosorbent assay (SMISA) was
achieved. Antigen from human immunodeficiency virus type 1 (HIV-1), the major etiological agent of acquired immune deficiency
syndrome, served as the screening target in this study. The target molecule was sandwiched between a polyclonal capture antibody
and a monoclonal detector antibody. The capture antibody was covalently immobilized on (3-glycidoxypropyl) trimethoxy silane-modified
glass slides. The detector antibody was conjugated with fluorescent Alexa Fluor 532 labeled secondary antibody prior to being
used as a probe for the antigen. Imaging was performed with a total internal reflection fluorescence single-molecule detection
system. This technique is demonstrated for detecting HIV-1 p24 antigen down to 0.1 pg/mL with a dynamic range of over four
orders of magnitude. A Langmuir isotherm fits the molecule count dependence on the target concentration. The target antigen
was further tested in 20% human serum, and the results showed that neither sensitivity nor dynamic range was affected by the
biological matrix. SMISA is therefore a promising approach for the early diagnosis of viral induced diseases. 相似文献