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921.
Wei‐Tao Cong Hong‐Zhang He Zhong‐Xin Zhu Cai‐Xue Ye Xu‐Yi Yang Jung‐Kap Choi Li‐Tai Jin Xiao‐Kun Li 《Electrophoresis》2010,31(10):1662-1665
An improved silver–ammonia staining method for DNA on polyacrylamide gels is described. In this method, staining of DNA using silver–ammonia complex allows high sensitivity, low cost, low toxicity, and simple protocol without requiring fixation and sensitization steps. The protocol takes less than 40 min to complete, with a detection limit of 1.5 pg of single DNA band on polyacrylamide gels, approximately 30‐fold higher than that of original silver–ammonia staining method. Furthermore, this novel technique not only exhibits high sensitivity for large DNA fragment, but also shows a better trend to detect low‐base‐pair DNA compared with other silver staining methods. 相似文献
922.
Nguyen Xuan Nhiem Phan Van Kiem Chau Van Minh Ninh Khac Ban Nguyen Xuan Cuong Le Minh Ha Bui Huu Tai Tran Hong Quang Nguyen Huu Tung Young Ho Kim 《Magnetic resonance in chemistry : MRC》2010,48(5):392-396
The chemical study of Momordica charantia fruits led to the isolation of three new cucurbitane triterpene glycosides, momordicosides U, V, and W (1–3). The structures of these compounds were determined to be (19R, 23R)‐5β, 19‐epoxy‐19‐methoxycucurbita‐6,24‐diene‐3β, 23‐diol 3‐O‐β‐D‐allopyranoside (1), (23R)‐5β, 19‐epoxycucurbita‐6,24‐diene‐3β, 23‐diol 3‐O‐β‐D‐allopyranoside (2), and (19R)‐5β, 19‐epoxy‐19,25‐dihydroxycucurbita‐6,23(E)‐diene‐3β‐ol 3‐O‐β‐D‐glucopyranoside (3), by chemical and spectroscopic methods. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
923.
M.K. Wu D.Y. Chen F.Z. Chien S.R. Sheen D.C. Ling C.Y. Tai G.Y. Tseng D.H. Chen F.C. Zhang 《Zeitschrift für Physik B Condensed Matter》1996,102(1):37-41
We have studied the double perovskite [1] structure Sr2Y(Ru1-x Cux)O6 system. The parent compound is an antiferromagnetic insulator with Neel temperature ~ 26 K. Partially substituted the Ru ion by Cu the compounds increase their conductivity drastically and eventually become superconducting. More intriguingly is the observation of the coexistence of superconductivity and magnetic ordering. The superconducting transition temperature T c and the magnetic ordering temperature T m are of the same order. The observed magnetic structure and superconductivity of these compounds can be understood in terms of a plausible theoretical model based on the double exchange idea. 相似文献
924.
925.
926.
Tai‐Peng Tsai 《Archive for Rational Mechanics and Analysis》1998,143(1):29-51
This paper proves that Leray's self‐similar solutions of the three‐dimensional Navier‐Stokes equations must be trivial under
very general assumptions, for example, if they satisfy local energy estimates.
(Accepted April 7, 1997) 相似文献
927.
A governing equation describing the mass-transfer fluxes in practical membrane formation is derived using Markoffian and Onsager's thermodynamic systems. This equation unambiguously demonstrates that isothermal mass-transfer fluxes at the spinodal composition may not be zero for systems operated in the gravitational field. This study suggests that the mass transfer equations derived by Cheng and Gryte are a special case of the present study and are not fully capable of describing the mass transfer in practical membrane formation. Experimental results published in previous literature qualitatively support our assessment. The limitations of using Markoffian and Onsager's thermodynamic systems for membrane formation study are also reviewed. In conclusion, new thermodynamic theories for polymer solutions are needed to quantitatively describe the mass transfer fluxes in practical membrane formation. 相似文献
928.
用一种参数化的形式研究了弦上具有硬胶子纽结所导致的有效弦张量的增长,在此种形式下强子一强子碰撞中有效弦张量随碰撞能量的增加而增加是来自碰撞中微喷注的产生,这种机制既能解释强子一强子碰撞奇异夸克压低因嵶铀媾鲎材芰恐龆龅男形帜芙馐停澹澹蚊恢懈靡蜃佑肽芰拷莆薰氐南窒蟆 相似文献
929.
Y. Tai J. Murakami K. Saito M. Ikeyama K. Tajiri M. Watanabe S. Tanemura T. Mizota 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):261-263
Plasma desorption mass spectrometry has been applied to
characterization of dodecanthiol-passivated gold nanoparticles.
An overview of the experimental set-up and mass analyses for the
nanoparticles prepared in different conditions are shown. Mass
distributions were found to shift to higher mass regions with
increasing reaction temperature and reaction period. The results
are consistent with those of transmission electron microscopy
observations, UV-visible absorption spectra and also with a
reported laser desorption mass spectrometry. 相似文献
930.
In this paper, we investigate the numerical identification of the diffusion parameters in a linear parabolic problem. The identification is formulated as a constrained minimization problem. By using the augmented Lagrangian method, the inverse problem is reduced to a coupled nonlinear algebraic system, which can be solved efficiently with the preconditioned conjugate gradient method. Finally, we present some numerical experiments to show the efficiency of the proposed methods, even for identifying highly discontinuous parameters.This work was partially supported by the Research Council of Norway, Grant
NFR-128224/431. 相似文献