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111.
P. de Gelder D. de Frenne E. Jacobs H. Thierens A. de Clercq P. Dhondt K. Heyde A.J. Deruytter G. Tittel N. Kaffrell N. Trautmann F. Schussler 《Nuclear Physics A》1980,337(2):285-300
The 102Mo activity was obtained by photofission of natural U and thermal-neutron induced fission of 235U, with subsequent chemical separation of the molybdenum fraction. In addition, nuclei with mass 102 were separated from fission products of 235U(nth, f) using the mass separator LOHENGRIN. A decay scheme and absolute γ-intensities are deduced from measured γ-ray, X-ray and γ-coincidence spectra. Logftvalues are calculated. Shell-model calculations for a multiplet have been carried out using effective nucleon-nucleon interactions. The γ-decay between low-lying, low-spin members of this multiplet was studied in detail and compared with the experimental data. 相似文献
112.
113.
Axisymmetric buckling of a complete spherical shell under uniform external pressure is treated by the spectral method. Among other results the lower critical pressures of 7% and 5% of classical linear buckling pressures are computed for radius-thickness ratios of 100 and 200 respectively. Both symmetric (non-physical) and non-symmetric buckling are computed. The non-symmetric buckled shapes at the two lower critical pressures mentioned are virtually identical. 相似文献
114.
J.R. Shepard R.E. Anderson J.J. Kraushaar R.A. Ristinen J.R. Comfort N.S.P. King A. Bacher W.W. Jacobs 《Nuclear Physics A》1979,322(1):92-108
Angular distributions have been measured for the low-lying levels of the residual nuclei for the 12C, 54Fe and 208Pb(p, t) reactions at Ep = 80 MeV. The shapes of these angular distributions are generally well reproduced by the zero-range distorted-wave Born approximation (DWBA). Enhancement factors extracted from the data show that the DWBA predicts relative strengths consistent with those observed at lower bombarding energies. However, the overall empirical DWBA normalization at Ep = 80 MeV is observed to be () of that required at 40 MeV for 208Pb (54Fe). 相似文献
115.
A computer model is presented for predicting traffic noise indices in built-up situations for free flow traffic conditions and for a flow interrupted by a traffic light. The stream of vehicles is simulated by a given time headway distribution, and a transfer function obtained from a 1 : 100 scale model is used to simulate the specific built-up situation. Different time headway distributions result in only very small discrepancies; even the simple “equally spaced” distribution is adequate for predicting noise indices with high accuracy, unless L90 has to be predicted. In eight built-up situations along a road with freely flowing traffic only minor mutual differences are found when L1 ? Leq and L10 ? Leq are compared, but L50 and L90, and consequently TNI and Lnp, show discrepancies of the order of 10 dB(A). If a traffic light is introduced the value of Leq rises compared with the free flow case, and the values of L1 and L10 increase, especially at higher traffic intensities, while L50 and L90 decrease. If the noise indices are calculated as a function of the distance along the road to the traffic light increases in L1, L10 and Leq are found at about 50 m beyond the traffic light. The principal cause for this increase appears to be the differences between the peak levels of an accelerating car and the sound level at the ultimate speed. More in situ measurements are required to test the accuracy of the model, especially for accelerating vehicles. 相似文献
116.
The cobalt, nickel and copper complexes of dithio-oxamidc have been characterized in terms of color, effect of pH, structure in solidion, order of addition of reagents, adherence to Beer's law and sensitivity. The reactivity of the reagent to other ions has been reported. A method for the simultaneous spectrophotometric determination of cobalt, nickel and copper has been developed. the results of the application of this procedure to synthetic samples and to several National Bureau of Standards Samples are given. 相似文献
117.
L.L. Coatsworth G.M. Bancroft D.K. Creber R.J.D. Lazier P.W.M. Jacobs 《Journal of Electron Spectroscopy and Related Phenomena》1978,13(3):395-401
Charged particle oscillator and hollow cathode He discharge lamps are described, and the performances of the two lamps in the same spectrometer are compared. Both lamps give high percentages of He(II) radiation, but the hollow cathode lamp gives higher overall He(I) and He(II) intensifies and has greater long term stability. The observed resolution for He(II) studies (~ 25 meV) is the same for both lamps. The C 2 s spectrum of CH 4 and the Hg 5 d5/2 spectrum of (CH 3) 2Hg demonstrate the performance of the hollow cathode lamp. In the CH 4 spectrum, a vibrational progression is observed, and attributed to the totally symmetric stretching mode. The linewidth of individual components increases at higher binding energy. The high resolution of the (CH 3) 2Hg spectrum enables us to identify additional peaks not previously seen in this spectrum. The Hg 5 d orbital energy-ordering for Me 2Hg is reassigned. 相似文献
118.
The magnetic circular dichroism (MCD) of thoroughly-quenched KBr: Sn2+ crystals has been measured over the temperature range 10–230 K. Theoretical calculations of the MCD line shape have verified that such crystals contain Sn2+ ions at centres that are principally of either cubic or tetragonal symmetry. The possibility that a small fraction of rhombic Sn2+ centres is also present is examined. The calculated spectra are in reasonable agreement with experiment over a wide temperature range, apart from the spectral region above 4.85 eV. The factors that might contribute to this discrepancy are discussed. 相似文献
119.
Konrad Jacobs 《Mathematische Annalen》1959,137(2):125-135
Ohne Zusammenfassung 相似文献
120.