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102.
The title compounds 1(a,b) and 1(c,d) were synthesized by (i) non-chelation controlled sodium borohydride reduction of their corresponding α-N,N-dibenzylaminoketones and (ii) the Aldol-type condensation of optically pure N,N-dibenzylaminoaldehydes with the lithium derivative of isobutyronitrile, respectively. Attempted inversion of configurations of these secondary alcohols using the Moriarty method yielded 4-chloro-3-N,N-dibenzylaminonitrile via an aziridinium ion intermediate instead of the expected inverted alcohols. 相似文献
103.
In 1-DE, proteins were traditionally mixed with the standard Laemmli buffer and boiled for several minutes. Recently, proteins dissolved in lysis buffer were used to produce better-resolved 2-DE gels, but thermal denaturation procedure still remained in some proteomic analysis. To determine the detailed effects of thermal denaturation on SDS-PAGE and MS, both 1-DE and 2-DE were performed using proteins heated at 100°C for different periods of time, and 17 protein bands/spots were positively identified by MALDI TOF/TOF MS/MS. Protein profiles on both 1-DE and 2-DE gels changed obviously and more polydisperse bands/spots were observed with increased heating time for over-heated samples. Based on these observations, an alternative protein marker-producing method was designed by directly dissolving protein standards without BSA into lysis buffer. This new kind of protein marker could be stored at room temperature for a long time, thus was more convenient for using and shipping. The identification of 17 proteins via MS and comparison of their identities revealed MASCOT-searched scores, number of both matched peptides, total searched peptides and sequence coverage became progressively lower with increasing denaturation intensity, probably due to the interference of thermal denaturation on trypsin cleavage efficiency and produced redundant modified peptides. Therefore, it was concluded that thermal denaturation not only changed the protein profiles and produced more polydisperse protein bands/spots, but also heavily interfered with the subsequent MS analysis, hence not recommended in future proteomic analysis for proteins dissolved in lysis buffer. 相似文献
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一种可用于分析任意介电常数张量的各向异性波导导模的二维时域有限差分模型 总被引:1,自引:1,他引:0
为分析具有任意介电常数张量的各向异性波导的导模,本文通过把简化的二维时域有限差分(2-DFDTD)法扩展至任意各向异性介质,提出了一种以D、E和H场为基础的统一的简化2-DFDTD模型.利用该模型,研究了简化的复数2-DFDTD方法与实变数2-DFDTD方法之间的关系.文中还讨论了复变数方法和实变数方法的激励技术. 相似文献
107.
Some sufficient conditions are obtained for the global exponential stability of periodic solutions to periodic bi-directional Cohen–Grossberg neural networks involving distributed delays, by using the Lyapunov functional method and some analytical techniques. These results improve and generalize some previous works, and are helpful for designing a global exponential stable periodic bi-directional Cohen–Grossberg neural networks. 相似文献
108.
Xiao Li Liu Ting Liu Anping Li Yarding 《Annals of Differential Equations》2005,21(3):465-468
In this paper, oscillatory properties of solutions for nonlinear impulsive hyperbolic differential equation are investigated and some new sufficient conditions are established. 相似文献
109.
本利用矩阵对的广义奇异值分解,得到了(AX,XB)=(C,D)有反中心对称解的充要条件,并给出了其通解的一般表达式,此外,还给出了此矩阵方程的解集合与给定矩阵的最佳逼近的表迭式. 相似文献
110.
522 W average power, spectrally beam-combined fiber laser with near-diffraction-limited beam quality
We report a three-channel, spectrally beam-combined (SBC), 1 mum fiber laser that produces 522 W of average power with near-diffraction-limited (M2 ~ 1.2) beam quality. The laser features a SBC power combining efficiency of 93%, versatile master-oscillator, power-amplifier fiber channels with up to 260 W of narrow-band, polarized, and near-diffraction-limited output that is tunable over nearly the entire 1 micro m Yb(3+) gain bandwidth, and excellent prospects for significant power scaling. To our knowledge, these results represent the highest beam quality and average power achieved to date for a beam-combined fiber laser system. 相似文献