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991.
A set of accurate measurements of the low temperature magnetoresistivity of dilute AlMn alloys is presented. By using an AlV alloys as a baseline, the resulting negative magnetoresistivity is obtained and compared with theoretical calculations.  相似文献   
992.
993.
994.
Several bis(ligand) octahedral complexes of iron(III) with salicylaldehyde semi-, thiosemi-, and S-methylthiosemi- carbazones have been synthesized and characterized by elemental analysis, conductivity and magnetic measurements, electronic and IR spectra, as well as by linear sweep and cyclic voltammetry. General procedures for the syntheses of all types of complexes have been established, giving better defined reaction conditions. Physicochemical properties of the novel complexes have been related to those of the already known compounds of the same type.  相似文献   
995.
We show that in large period modulated alloys the tricritical points curve begins at αc = 1/(1 + δ, where δ is the modulation amplitude. In the domain of the 2nd order transition, which appears smaller than in the homogeneous case, Hc21(T) and Hc31(T) are calculated.  相似文献   
996.
The process of plasma formation and rotation in a graphite tube in a magnetic field was observed by means of a high speed camera. Phenomena occurring in a transient period, before a state of steady rotation is reached, were recorded. Further, the mutual influence of two plasmas burning in the graphite tube under various conditions was studied.  相似文献   
997.
998.
A periodic dependence of the Stark parameters on the nuclear charge number for neutral and ion resonances has been found and discussed.  相似文献   
999.
Distant correlations are investigated within the framework of quantum mechanics. They are inherent to any physical situation in which two separated quantal systems are described by one composite state vector. Owing to correlations of this kind one can perform a measurement on one of the systems, thereby measuring a certain observable on the other (distant) system without interacting with it. Necessary and sufficient conditions are given for such a distant measurement to take place. It is found which are the observables that can be measured distantly, and which are the states of the distant system obtainable in this way. Solution of these problems is achieved by replacing the composite state vector by two entities equivalent to it: the reduced statistical operator of the system which is directly measured and a correlation operator. The latter gives a connection between states, observables, and probabilities of the two systems. Experimental evidence for distant measurement is discussed.  相似文献   
1000.
It is predicted that charged particles reflected from solid surfaces could emit radiation due to the change in their direction of motion upon reflection. The theoretical spectrum of this radiation is obtained for specular reflection. The general concept of ‘transition radiation’ is reconsidered to include this new effect which is found to dominate for low-energy, non-penetrating electrons and for high-energy electrons at grazing incidence.  相似文献   
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