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141.
The effect of including distortion (with and without exchange) in the wavefunction for the continuum electron while calculating
the probability of autoionization of 2s
2
1
S. 2s2p
1,3
P, 2p
2
1
D and 2p
2
1
S states of He and Li+ has been studied. 相似文献
142.
The total (p, n) reaction cross section for48Ca has been measured as a function of proton energy in the energy range 1.885 to 5.100 MeV with an overall resolution of ∼
2 keV and in ∼ 5 keV energy steps. The fluctutions in fine resolution data have been analysed to determine the average coherence
width 〈Γ〉. The excitation function averaged over large energy intervals has been analyzed in terms of the optical model. The
isobaric analogue resonances atE
p
∼ 1.95 and 4 MeV have been shape-analyzed to extract the proton partial width and the spectroscopic factorS
n
. A comparison of the gross structures observed in ∼ 55 keV averaged excitation function with the predictions of Izumo’s partial
equilibrium model has also been made. 相似文献
143.
V. N. Temlyakov 《Mathematical Notes》1998,63(6):785-795
We investigate a generalization of width in the sense of Kolmogorov suitable for estimating bestm-term approximations. We generalize Carl's inequality which gives lower estimate of Kolmogorov widths in terms of entropy numbers. Application of these new inequalities gives some progress in the problem of estimating bestm-term trigonometric approximations of multivariate functions.Translated fromMatematicheskie Zametki, Vol. 63, No. 6, pp. 891–902, June, 1998.This research was supported by the National Science Foundation under grant No. DMS 9622925 and by the ONR foundation under grant No. N00014-96-1-1003. 相似文献
144.
U. Brinkmann W. Hartig H. Telle H. Walther 《Applied Physics A: Materials Science & Processing》1974,5(2):109-115
The isotope specific two-step photoionization of metastable Ca atoms was investigated using a continuous wave dye laser and
an Ar+ laser. The photoionization was performed via a transition to an autoionizing state. Therefore an ionization probability as
high as 10−2 could be obtained. 相似文献
145.
We outline a recursive method for obtaining WKB expansions of solutions of the Dirac equation in an external centrally symmetric field with a scalar-vector Lorentz structure of the interaction potentials. We obtain semiclassical formulas for radial functions in the classically allowed and forbidden regions and find conditions for matching them in passing through the turning points. We generalize the Bohr-Sommerfeld quantization rule to the relativistic case where a spin-1/2 particle interacts simultaneously with a scalar and an electrostatic external field. We obtain a general expression in the semiclassical approximation for the width of quasistationary levels, which was earlier known only for barrier-type electrostatic potentials (the Gamow formula). We show that the obtained quantization rule exactly produces the energy spectrum for Coulomb- and oscillatory-type potentials. We use an example of the funnel potential to demonstrate that the proposed version of the WKB method not only extends the possibilities for studying the spectrum of energies and wave functions analytically but also ensures an appropriate accuracy of calculations even for states with nr 1.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 143, No. 1, pp. 83–111, April, 2005. 相似文献
146.
The inelasticity effects in the production of pion pairs in the processγγ→ππ for real photons are investigated using the partial wave dispersion relations. The total cross sections for different photon
helicities are calculated. It is observed that this process is dominated by theππ final state interaction. A prediction for S* (997) →γγ decay width is also made.
Work supported financially by CSIR, New Delhi 相似文献
147.
The location of the membrane lipid bilayer relative to a transmembrane protein structure is important in protein engineering. Since it is not present on the determined structures, it is essential to automatically define the membrane embedded protein region in order to test mutation effects or to design potential drugs. beta-Barrel transmembrane proteins, present in nature as outer membrane proteins (OMPs), comprise one of the two transmembrane protein fold classes. Lately, the number of their determined structures has increased and this enables the implementation and evaluation of structure-based annotation methods and their more comprehensive study. In this paper, we propose two new algorithms for (i) the geometric modelling of beta-barrels and (ii) the detection of the transmembrane region of a beta-barrel transmembrane protein. The geometric modelling algorithm combines a non-linear least square minimization method and a genetic algorithm in order to find the characteristics (axis, radius) of a shape with axial symmetry which best models a beta-barrel. The transmembrane region is detected by profiling the external residues of the beta-barrel along its axis in terms of hydrophobicity and existence of aromatic and charged residues. TbB-Tool implements these algorithms and is available in . A non-redundant set of 22 OMPs is used in order to evaluate the algorithms implemented and the results are very satisfying. In addition, we quantify the abundance of all amino acids and the average hydrophobicity for external and internal beta-stranded residues along the axis of beta-barrel, thus confirming and extending other researchers' results. 相似文献
148.
149.
《Discrete Mathematics》2020,343(8):111926
We consider hereditary classes of bipartite graphs where clique-width is bounded, but linear clique-width is not. Our goal is identifying classes that are critical with respect to linear clique-width. We discover four such classes and conjecture that this list is complete, i.e. a hereditary class of bipartite graphs of bounded clique-width that excludes a graph from each of the four critical classes has bounded linear clique-width. 相似文献
150.
Pengtao Li 《Journal of Mathematical Analysis and Applications》2010,369(2):595-609
In this paper, we establish a link between Leray mollified solutions of the three-dimensional generalized Navier-Stokes equations and mild solutions for initial data in the adherence of the test functions for the norm of . This result applies to the usual incompressible Navier-Stokes equations. 相似文献