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991.
992.
993.
Laser treatment of a solid surface was modeled by applying an analytical theory as well as by using Monte Carlo simulations. The crystalline surface was assumed to be initially smooth and chemically uniform, that is free of impurities built into the structure. Creation of surface defects by a laser beam was assumed to have entirely random nature. In particular, the surface was assumed to have been scanned by the beam focused successively on randomly chosen points. In the course of the ablation process, the beam produces a pyramidal crater whose dimensions are proportional to the applied laser power. According to the assumed nature of the scanning procedure, the craters formed by the beam are allowed to overlap. The influence of the number of laser pulses and the crater dimensions on the structural and adsorptive properties of the surface were examined by analysis of the variation of the mean surface depth and the surface width. Changes in the adsorptive properties were also estimated by the calculation of the thermally programmed desorption (TPD) spectra of monomolecular adsorbates desorbed from laser-treated surfaces. Additionally, equilibrium adsorption isotherms were calculated for the obtained surfaces. 相似文献
994.
C. Foin A. Gizon D. Barnéoud J. Genevey J. Gizon D. Santos F. Farget P. Paris C. F. Liang D. Bucurescu A. Płochocki 《The European Physical Journal A - Hadrons and Nuclei》2000,8(4):451-454
The decay of the T
1/2 = 420 ns isomer in 151Er has been reinvestigated. The multipolarities of the decaying transitions have been established by measuring the electron
conversion coefficients. An I
π
= 67/2− assignment is proposed for this isomer with a π[h
112/4
d
32/1
d
52/−1]⊗ν[f
7/2
h
9/2
h
112/−1] configuration. 相似文献
995.
Michał Eckstein Bruno Iochum Andrzej Sitarz 《Communications in Mathematical Physics》2014,332(2):627-668
We give a new definition of dimension spectrum for non-regular spectral triples and compute the exact (i.e., not only the asymptotics) heat-trace of standard Podle? spheres \({S^2_q}\) for 0 < q < 1, study its behaviour when \({q\to 1}\) , and fully compute its exact spectral action for an explicit class of cut-off functions. 相似文献
996.
On three-electron bonds and hydrogen bonds in the open-shell complexes [H2X2]+ for X = F, Cl, and Br
The [H2X2]+ (X = Cl, Br) formula could refer to two possible stable structures, namely, the hydrogen-bonded complex and the three-electron-bonded one. In contrary to the results published by other authors, we claim that for the F-type structures the hydrogen-bonded form is the only possible one and the [HFFH]+ complex is an artifact as its wave function is unstable. For all analyzed molecules, the IR anharmonic spectra have been simulated, which enabled a deeper analysis of other authors' published results of IR low-temperature matrix experiments. Topological atoms in molecules and electron localization function investigations have revealed that the nature of the bond in three-electron-bonded structures is similar to the covalent-depleted one in F2 or HOO molecules, but the effect of removing electrons from the bond area is stronger. 相似文献
997.
A general algorithm of evaluation of the coefficients of molecular integrals (coupling constants) appearing in the direct configuration interaction method is derived. The configurations are assumed to be spin-adapted antisymmetrized products of orthonormal orbitals. No limitation is imposed either upon the reference state (the number of the singly occupied orbitals may be arbitrary) or upon the excitation multiplicity. 相似文献
998.
J. Zioło 《Chemical physics letters》1980,70(3):563-564
The results of measurements of Δ/E2 as a function of concentration for CCl4 solutions of iodobenzene are given and compared with earlier results for CCl4 solutions of fluoro-, chloro- and bromo-benzene. Terms contributing to the molar saturation constant for pure halogeno-derivatives of benzene have been calculated, using Kielich's theory. The change of sign of Δ/E2 for bromo- and iodo-benzene is explained. 相似文献
999.
The synthesis of 2-phenylsparteine-N16-oxide (7) and its perchlorate salt (7-H+) was carried out. On the basis of spectral data, and by comparison with appropriate sparteine-N-oxides, the mechanism of formation and the structures of the two new compounds were proposed. It was found, the basicity of the new N-oxide is unexpectedly high and comparable to the basicity of quaternary ammonium hydroxides. The structure and the strength of intramolecular H-bond in 7-H+ makes 7 an excellent “catcher” proton or specific ”sponge” proton. 相似文献
1000.