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981.
E. Z. Vintaikin V. A. Udovenko S. Yu. Makushev D. F. Litvin 《Russian Physics Journal》1987,30(3):261-265
The method of neutron diffraction is used to construct temperature dependences of the intensity of 110 antiferromagnetic reflection under the influence of compressive stresses = 0–150 MPa along [001]. Application of the stresses leads to an increase in the transition temperature, the transition being delayed in proportion to the increase in the load. On the other hand, the loading leads to a reduction in the magnetization jump for the antiferromagnetic sublattices. Thus, at > 100 MPa, the antiferromagnetic transformation takes on features of a second-order phase transformation. The transition which takes place in the stressed state is characterized by smoother rearrangment of short-order antiferromagnetic order into long-range order, as is evidenced by erosion of the transition boundary. The model proposed here — which does not ascribe the usual effect to uniaxial stresses on the antiferromagnetic transition in -Mn alloys — is based on the anomalous temperature dependence of the elastic constants.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 92–97, March, 1987. 相似文献
982.
Jorge D. Samur 《Probability Theory and Related Fields》1987,75(2):245-259
Summary Given a stationary, -mixing triangular array of Banach space valued random vectors whose row sums converge weakly to an infinitely divisible probability measure, necessary and sufficient conditions for the validity of the corresponding invariance principle in distribution are given. 相似文献
983.
J. D. Deuschel 《Probability Theory and Related Fields》1987,76(3):325-340
Summary An infinite lattice system of interacting diffusion processes is characterized as a Gibbs distribution on
with continuous local conditional probabilities. Using estimates for the Vasserstein metric onC[0, 1], Dobrushin's contraction technique is applied in order to obtain information about macroscopic properties of the entire diffusion process. 相似文献
984.
This is a sequel to Part I of A Subjective Bayesian Approach to the Theory of Queues. The focus here is on inference and a use of Shannon's measure of information for assessing the amount of information conveyed by the various types of data from queues. The notation and terminology used here is established in Part I. 相似文献
985.
Gordon D. Pusch 《General Relativity and Gravitation》1987,19(3):225-231
The Eötvös, Dicke, and Braginski experiments do not rule out the recent suggestion that the weak equivalence principle (WEP) might be violated at intermediate ranges (10–1 m r 104 m). I briefly discuss the problems inherent in Eötvös-type apparatus in searches for WEP-violating forces (hyperforces) between laboratory masses and suggest an alternative detector free of such problems. The proposed detector is driven by a hyperforce torque at the rotational frequency. If the detector is tuned to this frequency, the signal, enhanced by resonance, may be detected synchronously. I derive the response equations for the detector and discuss how spurious responses due to gravity torques may be suppressed.This essay received the third award from the Gravity Research Foundation for the year 1986-Ed. 相似文献
986.
Comodulation detection differences using noise-band signals 总被引:1,自引:0,他引:1
D McFadden 《The Journal of the Acoustical Society of America》1987,81(5):1519-1527
In a variant of the standard paradigm employed to study comodulation masking release (CMR), a narrow noise band was used as a signal in the presence of "cue" bands which had either the same or different temporal envelopes. The number of cue bands present ranged from zero to four; when there were two or four cue bands, they were either all presented at the same overall level or the spectral profile was "scrambled" in a haphazard manner. Different noise samples were presented within and across trials. The result was in the opposite direction from the standard CMR outcome; that is, better performance was obtained when the envelopes of the cue band(s) were uncorrelated with those of the signal band than when they were correlated. These comodulation detection differences (CDDs) ranged from a decibel or two up to 10-12 dB in different conditions, and were generally larger the more cue bands present. Standard CMR conditions, which were run as controls, revealed that the detectability of a tonal signal does not increase as the number of cue bands is increased from one to four-an outcome which differs from those obtained in profile analysis experiments. The data taken with the equal-level and the scrambled-level cues differed little in both the CDD and the CMR conditions. All noise bands were 100 Hz wide, and approximately 250 ms in duration. The signal band in CDD and the masker band in CMR were centered at 2500 Hz. The psychophysical procedure was two-interval forced choice. 相似文献
987.
Let (k,g) be the total scattering cross section of a three-dimensional quantum particle of energy K2 by a radial potential. Under the assumption it is shown that in the domain one has the asymptotics where the coefficient is is expressed explicitly in terms of the Gamma function. For nonnegative potentials, the domain of validity of this asymptotic is even larger. For potentials with a strong positive singularity, it is established that as. Similar results are obtained for the forward scattering amplitude.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 147, pp. 155–178, 1985. 相似文献
988.
The analysis of nuclear convection-current contributions to the transverseE 2 isoscalar and isovector form factors in12C initiated by Flanz et al. has been extended. It is shown that the continuity equation of the nuclear electromagnetic current provides the constraint needed to explain the behaviour of the form factors studied in the range 0<q<2fm–1. 相似文献
989.
R. Broda P. J. Daly J. McNeill R. V. F. Janssens D. C. Radford 《Zeitschrift für Physik A Hadrons and Nuclei》1987,327(4):403-408
The level structure of theN=81 nucleus149Er has been studied by γ-ray spectroscopy following the reaction92Mo+255 MeV60Ni. Yrast levels in149Er are established up to ~3.3 MeV, including 0.61 and 4.8 μs isomeric states. Most of the observed levels are interpreted as seniority-three states arising from the coupling of s1/2, d3/2 and h11/2 neutron holes with πh 11 2/n . Isomers identified in the reaction96Ru+255 MeV58Ni are tentatively assigned to151Yb. TheB (E2) values of high-spin isomers inZ=66?70,N=81?83 nuclei are surveyed. 相似文献
990.
H. Prade J. Döring W. Enghardt L. Funke L. Käubler 《Zeitschrift für Physik A Hadrons and Nuclei》1987,328(4):501-502
An (α, 2nγ) in-beam study of excited states in 142Nd revealed 27 new levels on top of the 6+ isomer. Nanosecond lifetimes were found for two levels. The measured excitation energies were compared with spherical shell-model predictions obtained from suitably truncated model spaces. 相似文献