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991.
992.
N Gorin F Bonisolli F T Heidema W Klop A A Williams 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1978,166(3):157-161
Changes in starch content and amylase zymograms were followed during storage of Golden Delicious and Cox's Orange Pippin apples. Although the former was stored at 3-4 degrees C under controlled atmosphere (3--4% O2; 7--8% CO2 by volume) and the latter in air at 17 degrees C, in both, the multiple forms of amylases remained active, even after the starch content decreased to zero. It is the lack of starch substrate, therefore, rather than of enzymes that limits the amylase action in the stored apple. 相似文献
993.
R.O. Williams 《Calphad》1983,7(3):175-183
We consider various methods of graphically representing the thermodynamics of an alloy of more than two components. A free energy slice in which the free energy is plotted versus a single component, the other components having fixed ratios, seems particularly useful. The compositional complexity along such slices is not a function of the number of components. One such diagram for each component would compose a complete set. 相似文献
994.
The effect of various physical vapor deposition parameters on the thermoelectric power of thin film (10 000 Å) Mo-Ni junctions deposited by electron beam evaporation was investigated in this study. The deposition parameters of interest were the substrate temperature, the deposition rate and the vapor source purity. The thermoelectric power of the thin film Mo-Ni junctions was dependent on the structure of the Mo thermoelectric element of the couple, the characteristics of which were significantly altered by varying the deposition parameters. Varying the deposition parameters caused a change in lattice imperfections in the metal, which changed the mean free path of the conduction electrons and the thermoelectric power of the couple. The parameters having the greatest effect on the thermoelectric power were the deposition rate and the substrate temperature. Couples deposited at a high deposition rate (10 000 Å min-1) and a high substrate temperature (? 300 °C) demonstrated e.m.f. characteristics closest to bulk values. 相似文献
995.
Kenneth L. Williams 《Pattern recognition》1975,7(3):125-137
This paper describes a syntactic method for representing the primitive parts of a pattern as nodes of a type of directed graph. A linear representation of the digraph can then be presented to a regular unordered tree automaton for classification. Regular unordered tree automata can be simulated by deterministic pushdown automata, so this procedure can be implemented easily. Regular u-tree automata and the corresponding generative systems, regular u-tree grammars are formally defined. Several results are shown which are applicable to all syntactic pattern recognition schemes involving the use of primitives. 相似文献
996.
J. E. Ffowes Williams 《Sadhana》1978,1(1):57-72
This paper is a review of the present state of understanding of aerodynamically generated noise.
Based on an invited lecture given at the Sixth Canadian Congress of Applied Mechanics, Vancouver, May–June 1977, and at the
Indian Academy of Science, Bangalore, July 1977 相似文献
997.
Observations are reported on the growth of crazes in PMMA immersed in a range of alcohols, some less active crazing agents and some mixtures of methanol and inactive agents. When there is substantial plasticization of the craze, the growth is adequately described by the fluid flow model. Mixtures are also explicable in these terms since the active agent is preferentially absorbed. For lower degrees of plasticization, the craze growth is small and probably relaxation controlled. 相似文献
998.
999.
1000.
The competing reactions between existing Ni silicides surrounded by Si and Ni were investigated by thermal annealing and MeV Si ion beam mixing. With high energy irradiation, the energy deposition at both interfaces, Ni/Ni silicide and Ni silicide/Si, is equal. Two MeV He~- RBS and TEM were used to obtain the reacted layer composition and epitaxial orientation, respectively. Also glancing angle Co K_a. X-ray diffraction was utilized to identify phase formation. The main results indicate that the existing silicides preferentially react with Ni layer, and that there are pronounced differences of Ni silicide phase transition between thermal annealing and MeV Si ion beam mixing, even though the mixing was performed in radiation enhanced diffusion regime. The results can be explained in term of the heat of silicide formation and surface energy change. 相似文献