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961.
The optimization of the flow-pattern for a multiple effect evaporator system is discussed as a vector minimum problem. First a new program to solve the design problem for various flow-patterns with no stream mixing or splitting and an arbitrary number of effects is described. Second the set of noninferior flow-patterns is generated by enumerating one-by-one for all flow-patterns. This method works well in synthesizing multiple effect evaporator configuration. 相似文献
962.
963.
The magnetization process in contact printing is considered to be the same process as an ideal anhysteretic magnetization process. In the anhysteretic magnetization process a self-demagnetization effect by an internal field is an important factor, especially at short wavelength. Therefore, the internal field effect should be evaluated dynamically depending on the instantaneous strength of the diminishing bias field. It was shown that such an anhysteretic magnetization process including the internal field effect can be represented as a first-order feedback system in an automatic control theory. Thus the numerical analyzing method for the anhysteretic magnetization was established, and excellent coincidence between the numerically computed result and the experimental result in the contact printing was obtained. Consequently the distribution patterns of the magnetization and the internal field in the duplicated tape was computed. 相似文献
964.
965.
The photoionization cross-sections of various deep impurities of interest in solar-grade silicon for photovoltaic cells, and
the corresponding energy levels, have been determined by steady state photo-induced currents in pn junctions or Schottky barrier
junctions irradiated simultaneously with two wavelengths of light. Light of about half the band-gap energy controls the occupancy
of the deep impurity level and the spectral dependence of the photocurrent on a higher photon energy light source then provides,
via the Lucovsky model, the photo-cross-section and the impurity energy level. The results obtained for Au and Pt in Si are
in agreement with those of Braun and Grimmeiss and the energy levels for Fe, Ti, and Ag obtained optically are in agreement
with those obtained by other methods. 相似文献
966.
Shinichi Tamura 《Pattern recognition》1982,15(6):477-483
This paper deals with a separation of strongly touching clusters using a concept of n-connectedness between pattern pairs, i.e., the number of paths between patterns. This new concept is similar to the concept of n-connectedness of graphs. Classification algorithms based on the number of independent paths and edge-disjoint paths are presented. It is shown that the latter has a transitivity. Finally, a simpler algorithm, i.e., a classification method based on the total number of paths, is presented. The proposed algorithm may be seen as an intermediate one between the ordinary connectedness algorithm and the maximal complete subgraph (MCS) algorithm. 相似文献
967.
Summary The permeation characteristics of polymer blend membranes from poly(vinylidene fluoride) and poly-(ethylene glycol) to aqueous polymer solution were investigated under carefully controlled conditions. The permeation characteristics were influenced significantly by the blend ratio, the temperature and time of heat treatment, which changed the structure of the resulting membranes. 相似文献
968.
969.
H. Tsukada Z. Asaki T. Tanabe Y. Kondo 《Metallurgical and Materials Transactions B》1981,12(3):603-609
. A rectangular plate of mixed copper-iron sulfide composed of bornite (Cu5FeS4) and troilite (FeS) was oxidized in an O2-Ar mixed gas stream at 1023 to 1123 K. At the start of the oxidation, iron was preferentially oxidized with the rapid formation
of a dense Fe3O4 layer of about 10 μm thickness on the sample surface, without the evolution of SO2 gas. Following this reaction, layers of both Fe3O4 and Fe2O3 grew on the sulfide surface in accordance with the parabolic rate law. The diffusion of iron through the oxide layers was
assumed to control the oxidation rate during this stage. The effect of oxygen partial pressure on the parabolic rate constants
was minor and an apparent activation energy of 126 kJ/mol was obtained. During the later stages of the reaction, when the
sulfur activity in the inner sulfide core increased, the oxidation proceeded irregularly to the interior of the remaining
sulfide with the formation of a porous oxide and the evolution of gaseous SO2. The remaining sulfide core was found to be
a mixture of bornite (Cu5FeS4) and djurleite (Cu1.96S).
H. TSUKADA, former Graduate Student at Kyoto University 相似文献
970.
Summary Random-coiled conformation of poly(L-leucine), which has -branched side-chain, was theoretically analyzed by a conformational energy calculation based on intra-residue interactions. Calculated characteristic ratio 7.62 was obtained by using the transformation matrix statistically averaged over the entire side-chain conformational space of L-Leu residue. This value is smaller than those of poly(L-phenylalanine) (11.24) and poly(L-tyrosine) (12.33) which have -branched side-chain. 相似文献