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101.
David London 《Linear and Multilinear Algebra》2013,61(1-2):107-117
A necessary and sufficient condition for a matrix to be stochastically similar to a matrix with equal diagonal elements is obtained Aand B are called Stochastically similar if B=SAS ? 1 where S is quasi-stochastic i.e., all row sums of .S are I. An inverse elementary divisor problem for quasi-stochastic matrices is also considered. 相似文献
102.
R. E. London 《Magnetic resonance in chemistry : MRC》1981,17(2):134-137
Carbon-carbon coupling constants have been observed in [90% 3-13C1]tryptophan and used to assign the 13C resonances of the indole ring. The results support a reassignment of C-5 and C-6 recently suggested on the basis of the reassigment of the corresponding resonances in indole. Coupling constants are compared with theoretical values obtained using a finite perturbation theory Blizzard-Santry program, and excellent agreement is obtained for the 1J(CC) values. The calculations predict that the Fermi contact contribution is dominant for all nJ(CC) couplings to C-3. 相似文献
103.
Present experiments in pursuit of the mass difference in the system have put a lower bound on this quantity of (at 95% C.L.). The same experiments also yield a local minimum in the log-likelihood function around , which is away from being zero. Motivated by these observations, we investigate the consequences of a possible measurement of , in the context of both the standard model and supersymmetric models with minimal flavor violation. We perform a fit of the
quark mixing parameters in these theories and estimate the expected ranges of the CP asymmetries in B decays, characterized by and , the interior angles of the CKM-unitarity triangle. Based on this study, we argue that, if indeed turns out to be in its currently-favored range, this would disfavor a large class of supersymmetric models. Indeed, of all
the models examined here, the best fit to the data occurs for the standard model.
Received: 14 December 2000 / Published online: 23 January 2001 相似文献
104.
105.
High-performance capillary electrophoresis of histones. 总被引:1,自引:0,他引:1
A high-performance capillary electrophoresis (HPCE) system was developed for the fractionation of histones. This system involves electroinjection of the sample and electrophoresis in 0.1 M phosphate buffer (pH 2.5) in a 35 cm x 50 micron I.D. coated capillary. Electrophoresis was accomplished in 9 min, separating a whole histone preparation into its components in the following order of decreasing mobility: (MHP) H3, H1 (major variant), H1 (minor variant), (LHP) H3, (MHP) H2A (major variant), (LHP) H2A, H4, H2B and (MHP) H2A (minor variant), where MHP is the more hydrophobic component and LHP is the less hydrophobic component. This order of separation is very different from that found in acid-urea polyacrylamide gel electrophoresis and in reversed-phase high-performance liquid chromatography and, thus, brings the histone biochemist a new dimension for the qualitative analysis of histone samples. 相似文献
106.
107.
108.
C. J. Keane B. J. MacGowan D. L. Matthews R. A. London S. Maxon M. D. Rosen J. L. Bourgade A. Decoster S. Jacquemot M. Louis-Jacquet D. Naccache 《Applied physics. B, Lasers and optics》1990,50(4):257-264
Recent Ne- and Ni-like X-ray laser experiments carried out at the Centre d'Etudes de Limeil-Valenton (CEL-V) are reviewed. A variety of experiments in Ne-like X-ray lasers were performed; here we discuss measurements of soft X-ray amplification in Ge (Z=32) and Sr (Z=38) plasmas. In Ge plasmas produced by 0.53-m laser light at an irradiance of 6.0×1013 W/cm2, gains between 2.2–2.5 cm–1 on the 232.2 and 236.2 Å J=2–1 lines and a gain of 1.0 cm–1 on the 196.1 Å J=0–1 line were measured. In addition, gains of 4.4 cm–1 and 4.0 cm–1 have been demonstrated on the J=2–1 transitions at 164.1 and 166.5 Å in Nelike Sr at laser intensities of 1.3×1014 W/cm2. The effects of pumping the Ne-like Se X-ray laser with 0.35-m laser light have also been investigated; the Se lasing spectra is similar to that obtained with 0.53-m light. Experiments have also been carried out to optimize the gain of the 50.3 Å Ni-like Yb (Z=70) J=0–1 line. For Yb, no significant increase in gain over that previously reported was seen, but the time history of the Ni-like Yb X-ray laser was measured for the first time. Finally, attempts to extrapolate the Ni-like results to shorter wavelength were made using Ta (Z=73), W (Z=74), and Re (Z=75). No definitive observation of the Ni-like J=0–1 lasing lines was made in these experiments. 相似文献
109.
110.
M. G. Schifrin A. S. Jurowski S. G. Aronow M. E. London A. P. Shadanowskaja K. M. Gontscharenko E. B. Berger F. petl A. van Ahlen R. Kattwinkel H. Brükner W. Ludewig H. Jentzsch B. Vajagi A. L. Godbert W. J. Müller E. Jandl und L. Sümegi 《Fresenius' Journal of Analytical Chemistry》1936,104(5-6):234-238
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