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991.
A formula is given to describe the variation of intrinsic coercive force with packing in elongated single domain (ESD) iron particle assemblies. A similar formula, which describes this variation in barium ferrite particle assemblies, is formally identical to the other one by simply changingp (packing) into1 - p (porosity). Magnetic interactions are considered, and an overall interaction field is defined that may account for intrinsic coercive force variations in the case of ESD iron particles. Experimental results on barium ferrite particle assemblies are presented that suggest the existence of a critical packing factor (p sim 0.15 ) separating two different, but not specified, modes of interaction. 相似文献
992.
H. L. Martin A. G. Imgram 《JOM Journal of the Minerals, Metals and Materials Society》1965,17(7):735-741
Numerous alloys are evaluated for their structural usefulness in terms of ductility and notch toughness at cyrogenic temperatures. Alloys being evaluated include those of aluminum, nickel, steel, titanium and magnesium. 相似文献
993.
994.
R.LeB. Hooke M. Mellor W.F. Budd J.W. Glen A. Higashi T.H. Jacka S.J. Jones R.C. Lile R.T. Martin M.F. Meier D.S. Russell-Head J. Weertman 《Cold Regions Science and Technology》1980,3(4):263-275
Systematic knowledge of the mechanical properties of ice is a fundamental requirement for the solution of a wide range of problems in the earth sciences and engineering. Past research has been characterized by specialized studies, involving a variety of motivations and scientific disciplines, without much overall coordination. When the results of this research are synthesized, a reasonably coherent picture emerges, but there are major gaps in knowledge. From the deduced behavior of ice, and from informed speculation where data are lacking, a coherent plan for future research can be developed. This report summarizes existing knowledge and proposes experiments and test programs for a new research thrust. The studies that are proposed can be expected to yield significant benefits in glacier studies, ice engineering, and the mechanics of frozen ground. 相似文献
995.
996.
Mineka Susan; Selligman Martin E.; Hetrick Michael; Zuelzer Kathy 《Canadian Metallurgical Quarterly》1972,79(3):377
Produced conditioned drinking in 73 male Sprague-Dawley albino rats by conditioned stimuli paired with hypertonic procaine, isotonic procaine, and hypertonic saline, in that order of effectiveness. When these solutions were paired with the taste of saccharin, they produced taste aversions in the same order of effectiveness. Lithium chloride, a well-known poison, produced taste aversions but, in contrast, conditioned decreases in drinking. Like taste aversions which develop after 1 trial, conditioned drinking also developed in 1 trial. Results suggest that procaine and hypertonic saline may be poisons, since the malaise they produce is relieved by drinking, can be classically conditioned, and is indexed by conditioned drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Analyses of the fatty acid composition of 2 methyl ester mixtures and 13 oils, obtained by collaborators from the AOCS Smalley
Gas Chromatography Check Program, were treated statistically. The statistical data may be interpreted to indicate groups of
analysts who made a good, satisfactory or poor analysis. The data also indicate the relative degree of difficulty of analyzing
the various oils. Coconut oil was the most difficult to analyze while safflower oil offered the least difficulty. A comparison
of the precision of results employing the thermal conductivity detector and the flame ionization detector shows no difference.
Presented at the AOCS Meeting, Minneapolis, October 1969. 相似文献
998.
999.
An experimental class-BD amplifier circuit is reported, which confirms the previously announced principle of the circuit. Although slightly more complex than the conventional class-AD circuit, filtering problems are simplified, and it may have applications as a high-power amplifier. 相似文献
1000.
Errechnung der Zustandsgrößen des Hochofenverfahrens mit Hilfe eines induktiven und eines deduktiven Modells. Theoretische Grundlagen und mathematische Abhandlung der beiden Modelle. Plausibilitätskontrolle und Berechnung der system- und zeitabhängigen Parameter der Modelle und des Regelvektors im Modulator. Beschreibung des Regelalgorithmus anhand des Zustandsraumes und des Zustandsschaubildes. 相似文献