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951.
952.
The characteristics of radio-frequency (RF) plasma sheaths have been topics of much scientific study for decades, and have
also been of great importance in the manufacture of integrated circuits and fabricating microelectromechanical systems (MEMS),
as well as in the study of physical phenomena in dusty plasmas. The sheaths behave special properties under various situations
where they can be treated as collisionless or collisional, single-or dual-RF, one-or two-dimensional (1D or 2D) sheaths, etc.
This paper reviews our recent progress on the dynamics of RF plasma sheaths using a fluid method that includes the fluid equations
and Poission’s equation coupled with an equivalent circuit model and a hybrid method in which the fluid model is combined
with the Monte-Carlo (MC) method. The structures of RF sheaths behave differently in various situations and plasma parameters
such as the ion density, electron temperature, as well as the external parameters such as the applied frequency, power, gas
pressure, magnetic field, are crucial for determining the characteristics of plasma sheaths. 相似文献
953.
954.
Different intermittent curing methods were conducted for pulsed laser induced photopolymerization reactions in a TMPTA acrylic
system. Two methods of curing were compared, named grouped pulses impingement (GPI) and consecutively pulsed curing (CPC),
respectively, in which the total number of the curing pulses were kept same. In GPI, a prominent light diffraction effect
was observed in the post curing process, but was absent in the CPC procedure. A condensed but limited sized core of polymeric
structure was the cause of the light diffraction. The amount of inhomogeneity in the refractive index for the core was about
90% of the cured background. Simulations based on Fresnel diffraction theory were performed, and the result was in good agreement
with the experimental observations.
PACS 42.25.Bs; 61.82.Pv; 82.35.-x 相似文献
955.
The potential energy curve of MgH+ and the potential energy surface of Mg2H+ are calculated by quantum chemical ab initio SCF MO method with STO-3G basis set. The electronic wave functions and populations are obtained. The eqilibrium internuclear distance of MgH+ is 1.60 Å. There are two possible configurations of Mg2H+: C and D . The former is (Mg-Mg-H)+, with bond length rMg-Mg = 2.41Å and rMg-H =1.63Å. The latter is (Mg-H-Mg)+, with bond length rMg-H = 1.73Å. The cause of the stability of these species is discussed. The result of calculation about the bond length of MgH+ agrees reasonably well with experimental value. The conclusion about the stability of (Mg-Mg-H)+ ion supports the hypothesis proposed by Porter, based on thermodynamical calculation. 相似文献
956.
957.
Masaru Tsukada 《Zeitschrift für Physik A Hadrons and Nuclei》1974,270(4):351-360
A new theory for the random system with electron correlation is presented, which is an extension of the Hubbard's theory for the random system and also an extension of the CPA for the interacting electron system. The equation of motion for the Green function is solved by the same decoupling method used by Hubbard. The self-consistent relations for the Green function, the self-energy and the effective occupation number are derived. It is predicted in the binary alloy system that tails or satellites of the state density are produced by the combined effect of the randomness and electron correlation. The origin of the tail is the inelastic scattering of the electron byA — B atomic pairs, whose electronic configuration is changed during the scattering. Numerical calculations are reported for a simple model. 相似文献
958.
Makoto Tsukada 《Journal of Approximation Theory》1984,40(4):301-309
Let X be a reflexive, strictly convex Banach space such that both X and X* have Fréchet differentiable norms, and let {Cn} be a sequence of non-empty closed convex subsets of X. We prove that the sequence of best approximations {p(x ¦ Cn)} of any x ε X converges if and only if lim Cn exists and is not empty. We also discuss measurability of closed convex set valued functions. 相似文献
959.
A relationship between the Berlekamp-Massey and the Euclidean algorithms for linear feedback shift register synthesis is established.
In fact, by refining a sequence of polynomials appearing in the Euclidean algorithm, the sequence of characteristic polynomials
computed by the Berlekamp-Massey algorithm will be achieved.
A preliminary version of this paper was presented at the Oberwolfach Information Theory Meeting, May 12–16, 1986. 相似文献
960.