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101.
A relativistic mean field approach is used to determine and compare the single-particle Dirac potentials for nuclei and hypernuclei (Λ, Σ, Ξ). A simple model is used and the Dirac-Hartree-Fock equations are reduced to a Schrödinger-like equation. The subsequent central and spin-orbit shell-model potentials are compared to those of phenomenological approach and other recent microscopic approaches. In the case of hypernuclei the Hartree approximation works already quite well without any need of taking into account the strangeness exchange part coming from strange mesons. The influence of the anomalous magnetic moment of the baryon on the spin-orbit term is found to be rather important for both Λ- and Σ-hyperons.  相似文献   
102.
Events with a positive particle of large transverse momentum emitted at medium angles have been studied using the split field magnet spectrometer at the CERN-ISR at a c.m. energy of √s = 52.5 GeV. Positive particles with large longitudinal momentum, |x| > 0.5, i.e., leading particles, associated to large pT events, are analysed.  相似文献   
103.
Data from a neutrino and antineutrino hydrogen experiment with BEBC are used to investigate transverse properties of the produced charged hadrons. Measurements are presented on average transverse momenta of charged pions as functions of Feynman-x and the hadronic mass, on the transverse momentum flow within an event and on jet-related quantities. The main features of the data are well described by the LUND model. The data favour a version of the model in which soft gluon effects are included and the primordial transverse momentum of the quarks in the proton is small. Effects from 1st order QCD (hard gluon emission) are negligible.  相似文献   
104.
A method is described for the separation and automated fluorimetric determination of epinephrine and norepinephrine in brain tissue extracts without mutual interference. The catecholamines are isolated and purified by extraction from activated alumina. Oxidation and rearrangement to their fluorescent lutines is carried out on two separate AutoAnalyzer manifolds and fluorescence is read in an Aminco-Bowman spectrophotofluorimeter. The interference by one amine with the determination of the other is less than 1% for determination of epinephrine in the presence of an equimolar concentration of norepinephrine, and, conversely, less than 4% for determination of norepinephrine. This eliminates the need for solution of simultaneous equations, the results of which are often misleading when the ratio of one amine to the other in brain exceeds 10:1. This method can be useful for rapid screening of psychoactive compounds affecting central and peripheral adrenergic stores.  相似文献   
105.
Differential cross sections and analyzing powers from the inelastic scattering of 65 MeV protons leading to the 1+T=0 (12.71 MeV) and 1+T = 1 (15.11 MeV) states in 12C have been analysed as tests of a model two-nucleon t-matrix.  相似文献   
106.
The major product of acid-catalysed hydrolysis of 4α,5-epoxy-3β-methoxy-5α-cholestane (5) has been shown to be the allylic alcohol 9 (R = H) and not diol 10 as previously reported. A preparation of the latter compound, and of a number of cholestane derivatives with oxygen substituents in rings A and B, is described.  相似文献   
107.
A new method to calculate diffractive mass spectra has been developed. It is applied to K-p interactions at 10 and 16 GeV/c. Cross sections and mass spectra are given for the difractive dissociation processes p→(N+) and K-p→(K+) for i = 1 to 5 and also summed over all multiplicities. In addition to the diffractive peak at low mass coming from low multiplicities, a long tail extending to high masses and high multiplicities has been found. The multiplicity structure of diffraction dissociation can be understood in the context of the two-step dynamical picture of Pokorsky and Van Hove.  相似文献   
108.
We present a small $ \ddot x + (\delta + \epsilon \cos t + \epsilon \cos \omega t) x=0 $ \ddot x + (\delta + \epsilon \cos t + \epsilon \cos \omega t) x=0   相似文献   
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