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91.
Falko Lorenz 《Mathematische Annalen》1971,195(2):315-320
Ohne Zusammenfassung 相似文献
92.
Photoelectrons ejected from cesium atoms by circularly polarized light of certain wavelengths are highly spinpolarized according to Fano's theory. Measurements of the spinpolarization of photoelectrons along the wavelength spectrum are reported. The highest degree of spinpolarization obtained experimentally is 100%. Our results reveal a small deviation from the theoretically predicted spinpolarization. Apart from giving information on the influence of spin-orbit interaction on the photoionization process, the Fano-effect turns out to be a simple and efficient method for producing polarized electron beams. Though not designed as a polarized electron source, our present apparatus yields a beam of 0.3·10?10 Ampere with a polarization of 81 ± 3% when a broad unfiltered spectral band is irradiated. 相似文献
93.
94.
The angle and energy dependence of differential cross sections σ(E, θ) that exhibit diffraction oscillations is analyzed by a Regge representation. It is shown that: (1) the Regge poles can be estimated directly from the measured σ(E, θ); (2) a fixed-energy Regge pole calculation can reproduce the E-dependence of σ(E, θ). 相似文献
95.
Falko Lorenz 《Archiv der Mathematik》1979,32(1):458-468
Ohne Zusammenfassung 相似文献
96.
Hans U. Gerber 《Insurance: Mathematics and Economics》1982,1(1):13-18
The paper develops a method for the numerical evaluation of the distribution of aggregate claims and its stop-loss premiums. 相似文献
97.
P. R. Gerber 《Applied Physics A: Materials Science & Processing》1981,25(3):259-268
Computer calculations of the optical transmission of TN-LCDs as a function of the applied voltage are presented. In particular,
the wavelength and angular dependence of half transmission voltages and sharpness of transmission curves are examined. Furthermore
the lowest relaxation rates of the linearized dynamical equations, neglecting backflow effects are calculated. The dielectrical
anisotropy and the elastic parameters are varied systematically in the calculations over ranges that actually occur in nematics.
Although the results are too complex to be condensed in simple general statements they are helpfull in designing optimal nematic
mixtures for a given display application. 相似文献
98.
Electrochemical Formation of Δ1,2-Norbornene The electrochemical reduction of 1,2-dihalogen norbornanes in tetrahydrofuran/furan leads to a mixture of two isomeric cycloadducts 6 and 7. The ratio of these adducts corresponds to those which have been found in reductive bisdehalogenation of 1 and 2 by butyllithium. 相似文献
99.
Kampschulte L Griessl S Heckl WM Lackinger M 《The journal of physical chemistry. B》2005,109(29):14074-14078
Stable adsorption of 1,3,5-tris(4-pyridyl)-2,4,6-triazine (TPT) molecules from the liquid phase was only observed in binary solutions, that is, in the presence of a second (adsorptive) species. The process of mediated coadsorption of a molecular species at the liquid-solid interface was accomplished through complexation of TPT with a second type of molecule acting as a "molecular glue" via hydrogen bonds. Scanning tunneling microscopy (STM) was utilized to investigate the structure of the coadsorbed monolayers at the liquid-solid interface. Trimesic acid (TMA) and terephthalic acid (TPA)--both benzene rings with disposed carboxylic acid groups-were appropriate to precipitate the stable adsorption of TPT. According to the different symmetry and number of carboxylic acid groups, various networks were observed. 相似文献
100.
We consider the effect of distributed delays in predator-prey models and ecological food webs. Whereas the occurrence of delays in population dynamics is usually regarded a destabilizing factor leading to the extinction of species, we here demonstrate complementarily that delay distributions yield larger stability regimes than single delays. Food webs with distributed delays closely resemble nondelayed systems in terms of ecological stability measures. Thus, we state that dependence of dynamics on multiple instances in the past is an important, but so far underestimated, factor for stability in dynamical systems. 相似文献