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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
L. P. Smol'skaya S. P. Panova S. G. Kuznetsova V. P. Il'kin L. S. Danyushkin 《Journal of Applied Spectroscopy》1992,56(2):170-173
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 56, No. 2, pp. 259–263, February, 1992. 相似文献
992.
The kinetics of the anion-induced (5 × 20) → (1 × 1) surface structural transition of reconstructed Au(100) electrodes was studied in sulfate-containing solutions by current transients. It is shown that lifting of the reconstruction follows a nucleation-and-growth type behavior which can be described by the Avrami equation. Moreover, for high positive potentials, i.e., high anion coverages, the current-transient analysis reveals instantaneous nucleation, whereas for low transition overpotentials and long transition times a mechanism with constant transition rate prevails. Apparent activation energies, which depend strongly on the electrode potential, are derived from the temperature dependence of the Avrami plots. 相似文献
993.
Within the framework of a simple electrostatic model, as compared to recent experimental results, we here discuss the stability
of very weakly bound molecular negative ions. In contrast with the case of conventional valence anions, the excess electron
is then located in a very diffuse orbital and is mainly bound by electrostatic dipolar, quadrupolar, and polarization forces,
at large distances from the neutral molecular core. By fitting a single repulsion parameter of the model to the available
experimental data, it is possible to make quantitative predictions of the excess-electron binding energies in these species.
Critical values of the dipole moment, quadrupole moment or polarizability required for the observation of stable multipole-bound
negative ions are predicted and compared to available experimental data and ab initio calculations.
Received October 24, 2001; accepted for publication November 16, 2001 相似文献
994.
995.
Summary We study Sobolev space functions with prescribed growth properties on large spheres. In particular, we prove a weighted Poincaré
type inequality for such functions. An extension to weighted Sobolev spaces is sketched.
Sunto Si studiano funzioni che appartengono a certi spazi di Sobolev e che hanno crescita assegnata su sfere di grande raggio. Per tali funzioni si dimostra una disuguaglianza di tipo Poincaré con peso. Si indica inoltre anche una estensione di tale risultato a funzioni in spazi di Sobolev con peso.相似文献
996.
997.
A technique is proposed for improving the accuracy of the heat of fusion of semicrystalline polymers by DSC. The results of three commercially available instruments are compared. 相似文献
998.
The presented one-capacitor pinch driver, designed as a compact coaxial structure (including spark-gap and discharge section) consistent with the capacitor output, generates a current of 200 kA with 700 ns quarter-period, suitable for studying the optimization of Z-pinch radiative characteristics. The driver is described, measurements of its parameters summarized, and relations to our previous and future activities briefly reviewed.This work was supported in part by the Grant Agency of the Czech Republic under contract No. 202/93/1023. 相似文献
999.
1000.