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991.
992.
Krishna S Kumar 《Pramana》1993,41(1):45-53
We report on two sensitive tests of lepton universality carried out by the 4 LEP experiments at the Z0 pole. From measurements of the τ polarization in e+ e?→τ + τ ?, the ratios of the vector and axial vector coupling constants of the electron and the tau lepton to the weak neutral current are obtained to beg v e /g a e =0.066±0.015 andg V τ /g A τ =0.070±0.009 respectively. From measurement of the τ lifetime and the τ leptonic branching ratios, the ratio of the coupling constants describing weak leptonic decays of the τ and the μ is measured to beG τ /G μ =0.996±0.008. 相似文献
993.
A review is given of the StandardSU(5) supergravity model. This model has passed an important check regarding unification of the electro-weak and the strong couplings using high precision LEP data. It is shown that for a significant domain of the parameter space the model also satisfies constraints on the SUSY spectrum from CDF and LEP, as well as proton stability and cosmological relic density constraints. 相似文献
994.
Lucifer yellow and lissamine rhodamine sulfonyl hydrazine were used as the donor and the receptor, respectively, for Förster energy transfer measurements to determine the location of the subunit in the native Na,K-ATPase from pig kidney. It was found that (1) the subunits are located in one functional complex, i.e., the dimer ()2 appears to be the functional complex of Na,K-ATPase, and (2) the subunits in the functional enzyme complex in the membrane are not located next to each other but are rather well separated. The distance between fluorophores covalently attached to the subunits was found to be 5.3 nm. 相似文献
995.
996.
M. Pavičić 《International Journal of Theoretical Physics》1993,32(9):1481-1505
It is shown that an orthomodular lattice is an ortholattice in which aunique operation of bi-implication corresponds to the equality relation and that the ordering relation in the binary formulation of quantum logic as well as the operation of implication (conditional) in quantum logic are completely irrelevant for their axiomatization. The soundness and completeness theorems for the corresponding algebraic unified quantum logic are proved. A proper semantics, i.e., a representation of quantum logic, is given by means of a new YES-NO relation which might enable a proof of the finite model property and the decidability of quantum logic. A statistical YES-NO physical interpretation of the quantum logical propositions is provided. 相似文献
997.
998.
For benzenoid hydrocarbons the distribution of pi-electrons amongst rings is characterized in the context of Randis mode of assignment attending to the different Kekulé structures. In particular the mean and mean deviation from the mean are considered, and the benzenoids which achieve maximum deviation are identified. 相似文献
999.
J. Vaupotić 《Journal of Radioanalytical and Nuclear Chemistry》2001,247(2):291-295
On the territory of the abandoned uranium mine irovski vrh, Slovenia, indoor radon and gamma dose rate measurements were carried out in nineteen schools from February 10 to May 10, 1995, using scintillation cells and etched track detectors for radon and thermoluminescence dosimeters for gamma-ray detection. In five schools indoor radon levels exceeded 400 Bq·m-3, which is the proposed Slovene action level. The maximum average radon value of 1600 Bq·m-3 and the maximum gamma-dose rate of 172 Sv·month-1 were found in the same school. According to the ICRP 65 methodology, annual effective doses from radon decay products ranged from 0.05 to 6.10 mSv for pupils and from 0.04 to 4.90 mSv for teachers. Gamma dose rates ranged from 0.05 to 0.19 mSv·y-1 for pupils and from 0.07 to 0.27 mSv·y-1 for teachers. 相似文献
1000.
The extended Koopmans’ theorem is related to Fukui function, which measures the change in electron density that accompanies
electron attachment and removal. Two approaches are used, one based on the extended Koopmans’ theorem differential equation
and the other based directly on the expression of the ionized wave function from the extended Koopmans’ theorem. It is observed
that the Fukui function for electron removal can be modeled as the square of the first Dyson orbital, plus corrections. The
possibility of useful generalizations to the extended Koopmans’ theorem is considered; some of these extensions give approximations,
or even exact expressions, for the Fukui function for electron attachment. 相似文献