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41.
A minimal normal extension of unbounded subnormal operators is established and characterized and spectral inclusion theorem
is proved. An inverse Cayley transform is constructed to obtain a closed unbounded subnormal operator from a bounded one.
Two classes of unbounded subnormals viz analytic Toeplitz operators and Bergman operators are exhibited. 相似文献
42.
A very important question in ultrarelativistic heavy ion collisions is that of thermalization of the high energy density quark
gluon plasma forud in the central rapidity region. Different approaches have been adopted by various authors to study this
thermalization problem. These include phenomenological string and capacitor plate models, perturbative QCD based parton cascade
models and the classical non-perturbative approach. In this paper we briefly review the earlier studies and discuss our work
which emphasizes the role of non-perturbative collective effects (classical chaos) in the thermalization of the plasma. In
particular, using classical equations of motion of a coloured parton in self-consistent colour fields, we have carried out
a 1+1 dimensional simulation of coloured partonic matter. We find that in certain parameter domains, the system exhibits chaotic
behaviour in non-abelian plasma oscillations, which then leads to thermalization of the plasma. 相似文献
43.
The collective nature of states in 66Zn has been studied by carrying out a deformed configuration mixing shell model calculation in model space. An effective interaction obtained for this space by Kuo has been used. The collective structure for 2 positive-parity bands and 5 negative-parity bands is identified. A qualitative understanding of the backbending at the J = 6+ state in the yrast positive-parity band is given in terms of the band crossing of the ground-state band and the more deformed excited band arising from 2p2h excitation to the orbit. Several high-spin members of the observed bands as well as in-band E2 transition strengths have been predicted. 相似文献
44.
45.
It is estimated that the ground state of 56Ni as given by the Kuo-Brown effective interaction modified to satisfy the restrictions imposed by the BE2 systematics contains about 13 particles in the shell. 相似文献
46.
Bhatt AI du Fou de Kerdaniel E Kinoshita H Livens FR May I Polovov IB Sharrad CA Volkovich VA Charnock JM Lewin RG 《Inorganic chemistry》2005,44(1):2-4
In situ EXAFS spectroscopic studies of uranium compounds in high temperature alkali chloride melts indicate the presence of oligomeric species. An investigation into UCl(3) and UCl(4) dissolved in LiCl reveals long range ordering of uranium atoms in the molten state which is not maintained on quenching. Studies of uranium dioxide dissolved in LiCl-KCl eutectic with HCl exhibit long range ordering in both molten and quenched states, and the EXAFS data can be modeled using multiple coordination shells. 相似文献
47.
48.
It is shown that the improved effective interactions in the fp shell imply the existence of an excited band of states which is much more deformed than the ground state band for some fp shell nuclei. Such states are to a certain extent analogous to the fission isomers occurring in heavy nuclei. Their experimental identification would be interesting and might also help to further improve the effective interaction. 相似文献
49.
The mechanism of energy transfer from Tb3+ to Nd3+ in glycerol:D2O solution at 280 K, 300 K and in its frozen glass at 80 K, 120 K, 190 K and 250 K has been examined. Analysis of the intensity and lifetime measurements of 5D4 level of Tb3+ shows that at 280 K and 300 K in solution the transfer rate varies as the square of the Nd3+ concentration. This suggests a dipole-dipole transfer in the glycerol:D2O solution. However, at lower temperatures up to 190 K, where the solution freezes into a glass, the dependence observed is linear at lower Nd3+ concentrations and quadratic at higher concentrations. Moreover, the linear concentration dependence becomes more pronounced as the temperature of the glass is increased. This linear concentration dependence of the transfer rate and its temperature dependence have been ascribed to the migrational transfer accompanying the multipolar transfer. The coefficients of both the interactions at the above temperatures have been calculated. 相似文献
50.
It is suggested that a single determinantal state in the neighbourhood of the Hartree-Fock state, having the minimum energy variance might be a ‘better’ intrinsic state for describing some of the low energy states of a nucleus. At higher excitation energies the resulting orbitals may provide a suitable single-particle basis for describing the nuclear level density at that energy. 相似文献