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1.
Detailed pH-dependent steady state and picosecond time-resolved tryptophan fluorescence studies on thiocyanate and azide complexes of horseradish peroxidase have been carried out. The fluorescence decay of the single tryptophan in these species was fitted to a discrete three exponential model. Maximum entropy method analysis also gave three distinct regions of lifetime distributions. The fast subnanosecond lifetime component was found to have > 97% amplitude contribution while other two longer lifetime components have small contributions. Small contributions from the nanosecond lifetime components possibly arise from apoprotein impurity or some small amount of disordered heme conformer of the protein. pH dependence of the fast picosecond lifetime components was found to show a systematic behavior which has been interpreted in the light of obligatory conformation change associated with activation of the enzyme at low pH.  相似文献   
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Recently Addy and Datta have obtained a linearized solution for isentropic motions of a perfect fluid by assigning Cauchy data on the hypersurfacex 4=0 and by imposing a restriction on the equation of state. In the present paper we pursue this study and discuss the problem of singularities from the standpoint of a local observer for which a singularity is defined as a state with an infinite proper rest mass density. It is shown that for a closed universe with any distribution of matter whatsoever there occurred a singularity in the past in the nonrotating parts of the universe and it must recur in the future. Furthermore, the collapse of a rotating fluid to a singularity seems inevitable when the relativistic equation of state is considered.  相似文献   
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In this paper, by exploiting recent results on the pathwise behavior of the workload process in single server, work conserving queues of theG/G/1/ type, we show that the workload of multiserver, work conserving queues ofG/G/m/ (m<) (andG/G/) queues satisfies an o(t) growth condition, provided that the time average of the work brought into the system is less thanm form < (and finite form=).  相似文献   
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The total ionization cross section in electron-hydrogen scattering in the energy range 20.4–68.0 eV has been calculated by a method in which the initial state of the system is treated by a distorted wave polarized orbital method and the final state is described by (1) a product of two unscreened Coulomb functions and (2) a product of a plane wave and a Coulomb function. The corresponding two sets of results using a plane wave in the incident channel have also been reported. The present results where both the electrons are represented by Coulomb waves are in closer agreement than other theoretical predictions With measured values.  相似文献   
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A method for the study of thermally induced vibrations of viscoelastic shallow shells of arbitrary shaped plane-form is proposed. It is shown that the time behaviour can be found by assuming a normal mode expansion in tems of the eigenfunctions of the associated elastic shallow shell problem and the deflection is obtained with the aid of the correspondence principle. The response of a shallow shell with rectangular as well as elliptical base to the sudden application of a temperature distribution on the surface of the shell is discussed. For rapidly applied heat inputs, an approximate analysis for its rapid estimation is also presented. All details are illustrated by graphs.  相似文献   
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Fusion excitation functions are measured for the system 6Li + 28Si using the characteristic $ \gamma$ -ray method, encompassing both the sub-barrier and above-barrier regions, viz, E lab = 7-24 MeV. Two separate experiments were performed, one for the above-barrier region ( E lab = 11-24 MeV) and another for the below-barrier region ( E lab = 7-10 MeV). The results were compared with our previously measured fusion cross-section for the 7Li + 28Si system. We observed the enhancement of the fusion cross-section at sub-barrier regions for both 6Li and 7Li , but the yield was substantially larger for 6Li . However, for well-above-barrier regions, a similar type of suppression was identified for both the systems.  相似文献   
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Abdullin  S.  Banerjee  S.  Bellucci  L.  Charlot  C.  Denegri  D.  Dittmar  M.  Drollinger  V.  Dubinin  M.N.  Dzelalija  M.  Green  D.  Iasvili  I.  Ilyin  V.A.  Kinnunen  R.  Kunori  S.  Lassila-Perini  K.  Lehti  S.  Mazumdar  K.  Moortgat  F.  Muller  Th.  Nikitenko  A.  Puljak  I.  Salmi  P.  Seez  C.  Slabospitsky  S.  Stepanov  N.  Vidal  R.  Wu  W.  Yildiz  H.D.  Zeyrek  M. 《The European Physical Journal C - Particles and Fields》2005,39(2):41-61
The European Physical Journal C - This work summarizes the studies for the Higgs boson searches in CMS at the LHC collider. The main discovery channels are presented and the potential is given for...  相似文献   
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