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81.
We evaluate the emissivity rates for d-decay and s-decay by exactly solving the angular integrals involved and without assuming
the degeneracy of electrons. We have also studied the effects of QCD coupling constant as well as the s-quark mass on the
emissivity rates. We find that these parameters are important in determining the threshold and extinction densities for d-
and s-decays. 相似文献
82.
83.
Distributed computing systems are becoming bigger and more complex. Although the complexity of large‐scale distributed systems has been acknowledged to be an important challenge, there has not been much work in defining or measuring system complexity. Thus, today, it is difficult to compare the complexities of different systems, or to state that one system is easier to program, to manage, or to use than another. In this article, we try to understand the factors that cause computing systems to appear very complex to people. We define different aspects of system complexity and propose metrics for measuring these aspects. We also show how these aspects affect different kinds of people—viz. developers, administrators, and end‐users. On the basis of the aspects and metrics of complexity that we identify, we propose general guidelines that can help reduce the complexity of systems. © 2007 Wiley Periodicals, Inc. Complexity 12: 37–45, 2007 相似文献
84.
85.
Young-Eun Im Uh-Chan Ryu P. Babu Won-Taek Han K. Oh David J. DiGiovanni Baishi Wang Anand Hariharan 《光学学报》2003,23(Z1)
Sb-doped silica EDF showed an opposite temperature dependent gain profile compared to Al-doped silica EDF. Concatenation of those two EDFs showed a gain variation less than ± 0.4 dB over 40nm of C-band with the 15dB gain, in the temperature range of - 40 to + 80℃. 相似文献
86.
Radio astronomical data available on the galactic background radiation has been carefully examined to deduce information on the existence or otherwise of a Galactic Radio Halo. It is shown that, though considerable doubt has been recently expressed by some regarding its existence, no convincing and quantitative reasoning has been so far advanced towards this; on the other hand, there are substantial arguments in its favour. 相似文献
87.
88.
Summary The general course of reactions between [MCl4 ]2– (M = Pd, Pt) and primary and secondary phosphines containing phenyl, cyclohexyl, or 2-cyanoethyl groups, in polar solvents, is to yield L3MCl2 complexes which are probably ionic [L3MCl]+Cl– These compounds can be isolated and characterized in the solid state, but in solution they are labile, and tend to react to give phosphines plus L2 MCI2. 相似文献
89.
K. C. Anand S. Biswas P. J. Lavakare S. Ramadurai N. Sreenivasan V. S. Bhatia V. S. Chohan S. D. Pabbi 《Proceedings Mathematical Sciences》1969,70(5):201-220
A detailed study of the composition and energy spectra of heavy nuclei of charge Z?3 in the primary cosmic rays has been made during the period of low solar activity, using two stacks of nuclear emulsions exposed in balloon flights from Fort Churchill, Canada, in June 1963. Each of the stacks was composed of 120 nuclear emulsions of three different sensitivities and was exposed at about 3·5 g. cm.?2 of residual air for about 11.1 hr. Reliable resolution of charges of nuclei from lithium to oxygen was obtained; for heavier nuclei, charge groups were determined. From the analysis of 793 tracks of nuclei with Z?3, results on the following aspects were obtained:
- The differential energy spectra of L (Z=3–5), M (Z=6–9) and H (Z=10–28) nuclei were measured in the energy intervel 150–600 MeV/nucleon; integral fluxes were obtained for energy >600 MeV/nucleon;
- The energy dependence of the L/M ratio at the top of the atmosphere was determined; the ratios were obtained as 0·45 ± 0·06 and 0·29 ± 0·03 in the energy intervals of 200–575, and >575 MeV/nucleon respectively;
- Relative abundances of individual nuclei of Li, Be, B, C, N and O at the top of the atmosphere were determined as 36, 29, 55, 100, 60 and 106 respectively in the energy interval 150–600 MeV/nucleon; corresponding values were also obtained for energy >600 MeV/nucleon.
- The differential fluxes of multiply charged nuclei measured by us and by other investigators were used to determine the solar modulation between solar maximum to solar minimum. It was found that solar modulation of the fluxes of M and He nuclei were consistent with Rβ dependence and that the modulation parameter Δη between 1965 and 1957 was about 1·1.
90.
Vineeta Taneja Madhu Anand C. L. Gupta S. B. Gupta R. L. Mital 《Journal of heterocyclic chemistry》1984,21(4):1239-1240
The synthesis of various substituted 1-hydroxy-2-chloroacetyl-6-thia-10b-aza-2a-azoniaaceanthrylene hydroxide inner salt, 1-hydroxy-6-thia-10b-aza-2a-azoniaaceanthrylene hydroxide inner salt, 1-hydroxy-2-piperidinoacetyl-6-thia-10b-aza-2a-azoniaaceanthrylene hydroxide inner salt is described. The ir is also included. 相似文献