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991.
Masaaki Watanabe 《Journal of statistical physics》1980,22(5):553-562
Mori's scaling method is used to derive the kinetic equation for a dilute, nonuniform electron plasma in the kinetic region where the space-time cutoff (b, t
c) satisfies
Dbl
f
,
D
t
c
f
, with
D the Debye length,
D
–1=
p
the plasma frequency, andl
f
and
f
the mean free path and time, respectively. The kinetic equation takes account of the nonuniformity of the order ofl
f and
D for the single-and the two-particle distribution function, respectively. Thus the Vlasov term associated with the two-particle distribution function is retained. This kinetic equation is deduced from the kinetic equation in the coherent region obtained by Morita, Mori, and Tokuyama, where the space-time cutoff of the coherent region satisfies
Dbr
0,
Dt
c
0, withr
0 the Landau length and
0 the corresponding time scale. 相似文献
992.
993.
994.
995.
996.
997.
998.
Hiroshi Masuhara Satoshi Ohwada Noboru Mataga Akira Itaya Ken-ichi Okamoto Shigekazu Kusabayashi 《Chemical physics letters》1978,59(2):188-192
Ionic photodissociation processes of vinyl polymers with pendant carbazolyl groups in solution have been studied by nonsecond laser photolysis. The ionic dissociation yield decreases in the order of monomer, oligomers, and polymers. 相似文献
999.
1000.
By comparing the photo-stimulated desorption of Xe from an oxidized Si(100) surface with the photochemistry of methane on metal surfaces, we try to deduce a common concept in the excited state and the excitation mechanism responsible for the photo-induced processes. Xe atoms are desorbed from the oxidized Si(100) surface by the irradiation of photons in the range 1.16-6.43 eV. Two velocity components with average kinetic energy 0.85 and 0.25 eV are observed in the time-of-flight distributions. The fast component appears only if the photon energy exceeds approximately 3 eV, but the slow component is present over the entire photon energy range. By analogy with the photochemistry of methane on metal surfaces, the excitation mechanism responsible for the fast component is postulated to be a transition from the 5p state of Xe to the excited state originating from strong hybridization between the 6s state of Xe and the dangling bond at a surface silicon atom bonded to oxygen inserted in the dimer bond. In this scheme an excited electron is transferred from the adsorbate to the substrate, which is the reverse direction to the substrate-mediated excitation frequently assumed in surface photochemistry. 相似文献