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61.
62.
Quantitative evaluation of protein recoveries in two-dimensional electrophoresis with immobilized pH gradients 总被引:5,自引:0,他引:5
In this study, metabolically radiolabeled Escherichia coli cell extracts were used to systematically evaluate protein recoveries at each step of two-dimensional (2-D) electrophoresis and using different sample application methods. Sample application using sample cups resulted in better protein recovery compared with sample loading by rehydration when the Multiphor system was used. At least 50% or more of an E. coli extract was lost when high protein amounts (500 microg) were loaded by rehydration using this system, which employs separate holders for rehydration and isoelectric focusing (IEF). In contrast, when the IPGphor system was used, rehydration sample loading consistently yielded the highest overall protein recoveries. These improved protein recoveries were due to integration of rehydration and electrophoretic separation in a single unit. Even at high protein loads (500 microg), less than 15-20% of the proteins were lost when proteins were loaded by rehydration using sample buffer containing 2% carrier ampholytes in the ceramic immobilized pH gradient (IPG) strip holders used for both rehydration and IEF. Regardless of the loading conditions used, carrier ampholytes in the sample buffer increased protein recoveries. Use of thiourea did not significantly affect protein recoveries but did improve protein resolution in 2-D gels as expected. In summary, these results show the best protein recoveries are obtained for all protein loads when samples are applied to IPG strips during rehydration using a single device for both rehydration and IEF. In contrast, the poorest recoveries are obtained when rehydration and IEF are performed in separate devices, and losses increase dramatically with increasing protein loads using this approach. 相似文献
63.
YingXinLIU ZuoJunWEI JiXiangCHEN JiYanZHANG XinXueLI XiongHuiWEI 《中国化学快报》2005,16(4):531-533
A novel lanthana-promoted nickel catalyst supported on silica for the liquid phase hydrogenation of m-dinitrobenzene to m-phenylenediamine was prepared by an incipient wetness sequential impregnation method. It was found that Ni-La/SiO2 catalyst exhibited high activity and stability for m-dinitrobenzene hydrogenation. Over this catalyst, the conversion of m-dinitrobenzene and the yield of m-phenylenediamine were up to 97.1% and 93.5%, respectively,at 373 K and 2.6 MPa hydrogen pressure after reaction for 1 h. 相似文献
64.
65.
Graphdiyne(GDY)has characteristics of one-atom-thick two-dimensional layers comprising of sp and sp2 hybridized carbon atoms.The chemical and electronic structure gives GDY many unique and fascinating properties,such as rich chemical bonds,highly conjugated and super-large π structures,infinitely distributed pores and high inhomogeneity of charge distribution,etc. 相似文献
66.
Wentong Gao Jianwei Xu Pengfei Zuo Hao Dong Yiwu Quan Pengshan Chang 《Journal of polymer science. Part A, Polymer chemistry》2019,57(13):1460-1466
The dynamic chemistry of disulfide bonds has emerged as one of the most powerful tools used for the fabrication of organic compounds and self‐healing materials. In this article, a novel aromatic amine‐terminated polysulfide oligomer is first synthesized from thiol‐terminated polysulfide oligomer and bis(4‐aminophenyl) disulfide via disulfide metathesis mechanism. The resulting oligomer is confirmed by FTIR and 1H NMR spectra and then successfully applied in constructing self‐healable polyurea material (A‐LP23‐I), which combines the advantages of higher strength of polyureas and excellent self‐healing ability of polysulfide‐based materials. After subjecting to a temperature of 75 °C for 48 h, both the tensile strength and ultimate elongation of A‐LP23‐I restore to more than 90% of the original values (3.32 MPa and 396%). This study demonstrates a novel strategy for synthesizing aromatic amine‐terminated oligomer. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1460–1466 相似文献
67.
Chao Zuo Qian Chen Guohua Gu Xiubao Sui Jianle Ren 《Infrared Physics & Technology》2012,55(4):263-269
In this paper, an improved interframe registration based nonuniformity correction algorithm for focal plane arrays is proposed. The method simultaneously estimates detector parameters and carries out the nonuniformity correction by minimizing the mean square error between the two properly registered image frames. A new masked phase correlation algorithm is introduced to obtain reliable shift estimates in the presence of fixed pattern noise. The use of an outliers exclusion scheme, together with a variable step size strategy, could not only promote the correction precision considerably, but also eliminate ghosting artifacts effectively. The performance of the proposed algorithm is evaluated with clean infrared image sequences with simulated nonuniformity and real pattern noise. We also apply the method to a real-time imaging system to show how effective it is in reducing noise and the ghosting artifacts. 相似文献
68.
Lihua Zuo Heng Meng Jingjing Wu Zhen Jiang Shuying Xu Xingjie Guo 《Journal of separation science》2013,36(3):517-523
In this study, the enantioseparation of zopiclone, repaglinide, chlorphenamine maleate, brompheniramine maleate, dioxopromethazine hydrochloride, promethazine hydrochloride, liarozole, carvedilol, homatropine hydrobromide, homatropine methylbromide, venlafaxine, and sibutramine hydrochloride has been investigated using β‐CD in combination with a chiral ionic liquid (IL), 1‐ethyl‐3‐methylimidazolium‐L‐lactate. The influence of the type of IL and its concentration, BGE pH, and chain length of the IL cations on the resolution are discussed. Finally, the proposed method was successfully applied for the chiral impurity determination of eszopiclone in pharmaceutical tablets after validation with respect to accuracy and precision, linearity range, selectivity, repeatability, LOD and LOQ. It is assessed that the chiral impurity determination in the commercial tables is fewer than 0.1%. 相似文献
69.
Dr. Shiyong Zuo Dr. Xijun Xu Prof. Shaomin Ji Zhuosen Wang Dr. Zhengbo Liu Prof. Jun Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(3):830-860
As concerns about the safety of lithium-ions batteries (LIBs) increases, aqueous zinc-ion batteries (ZIBs) with a lower cost, higher safety, and higher co-efficiency have attracted more and more interest. However, finding suitable cathode materials is still an urgent problem in ZIBs. In recent years, a lot of significant works have been reported, including manganese-based cathodes, vanadium-based cathodes, Prussian blue analog-based materials, and sustainable quinone cathodes. In this review, some typical cathode materials are introduced. The detailed storage mechanisms and methods for improving the reaction kinetics of the zinc ions are summarized. Finally, the issues, challenges, and the research directions are provided. 相似文献
70.
Zou Fan Zuo Jing Geng Chao Li Feng Huang Guan Liu Jiaying Jiang Jiali Fan Zhihua Li Xinyang 《Journal of Russian Laser Research》2021,42(4):462-467
Journal of Russian Laser Research - Laser aiming is one of the key technologies of laser atmospheric transmission. The beam actually is affected by atmospheric turbulence and mechanical vibration;... 相似文献