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901.
902.
Ko Sugihara 《Journal of Physics and Chemistry of Solids》1973,34(10):1727-1736
Thermoelectric power in antiferromagnetic semiconductors is calculated in the vicinity of the Néel temperature by assuming the presence of the well-defined propagating modes (magnon) and a temperature-dependent magnon velocity. Carriers are specified by the mobile carriers in a broad band with an isotropic effective mass. Magnons and carriers are coupled via the sd-interaction. Anomaly near TN does not result from the diffusion term Sdiff. and it is ascribed to the magnon-drag contribution Sdrag which is obtained from,where R(q) is the momentum transfer ratio between the magnon system and carriers, cm(q) denotesthe specific heat of the magnon q. The assumed temperature dependence of the magnon velocity makesSdru divergent at TN with TN ? T → +0 and it might be removed in consideration of the magnon frequency spreading. Except this divergence the calculation provides a qualitative explanation for the anomalous feature in MnTe. 相似文献
903.
T Fujii H Kanai J Mirayama K Handa S Kusama K Yano M Miyazawa M Takizawa 《Radioisotopes》1979,28(12):751-756
The dual radioisotope techniques with 201TlCl and 99mTcO4- were performed in 30 cases inclusive of various heart and lung diseases, using a scintillation camera coupling to a small digital computer. The scintigraphic procedures were started about 5 minutes after intravenous injection of 201TlCl. The myocardial images such as anterior, 60 degrees left anterior oblique, and left lateral view, were obtained. Next, 30 degrees left anterior oblique view was taken and radionuclide angiogram with 99mTcO4- was done in the same position too. This joint use of the myocardial imaging and radionuclide angiography could increase diagnostic reliability. Superimposing the image as iso-count map extracted out of radionuclide angiogram to the brightness image of 201TlCl, the anatomic orientation of the image of 201TlCl was improved. Subtracting the blood pool image with 99mTcO4- or radionuclide angiogram, which showed visualization of the right ventricle, lungs and left ventricle, from the image of 201TlCl, the subtraction image was obtained. The right ventricle was visualized more clearly on this subtraction image than the original image of 201TlCl. Good visualization of the right ventricle was shown in 25 cases on the subtraction image, and in 17 cases on the original image of 201TlCl. 相似文献
904.
For field intensities which are not too large or rapidly varying, weak excitation of non-resonant levels introduces a time dependent Stark shift of the resonant levels without affecting the total probability of the system being in the resonant levels. Some consequences of this for the theory of ultra-short pulse propagation in a resonant medium are considered. 相似文献
905.
V. Cook S. Csorna D. Holmgren A.M. Jonckheere H.J. Lubatti P. Malecki K. Moriyasu B. Robinson D. Fournier P. Heusse J.J. Veillet J.H. Klems W. Ko R.L. Lander D.E. Pellett 《Physics letters. [Part B]》1976,64(2):221-224
A measurement is made of the production correlation between neutral strange particles V and muons. The interactions originated in a streamer chamber containing a Lucite target bombarded by 225 GeV π? mesons. The experiment has a sensitivity of 10 events per nanobarn and yields no evidence for new particles. 相似文献
906.
907.
908.
A generalization of the theory for the photomagnetoelectric effect (PME) is reported. Experimental quantities such as short circuit current, open circuit voltage and magnetoresistance are described as functions of carrier lifetime, surface velocities at the sample surfaces, electron and hole mobilities, electron and hole concentrations, absorption and quantum efficiency coefficients, intensity of light, magnetic field and sample dimensions. The results of numerical computation are also presented. 相似文献
909.
On the basis of the symmetry of the free energy function describing properly the transition of gadolinium molybdate into the ferroelectric state, macroscopic relations are derived for the spontaneous birefringence and for the temperature dependence of the electrooptic coefficientsz ij . Since the transition parameters correspond to lattice vibrational modes with finitek, the resulting formulae differ considerably from those for classical ferroelectrics with transition parameterP. Experimental data are presented for the temperature dependence of freez 63 andz 41, clampedz 63 and free permittivity for a multidomain and single domain crystal. These results and earlier data on spontaneous birefringence compare well with theory. 相似文献
910.
Summary The application of the theory of experimental designs and empirical polynomial models in the Generalized Standard Addition Method is proposed. Standard additions are made according to a plan, for example 2sun factorial. The concentrations of analytes are simply calculated and the error analysis is clear. The procedure is explained in detail by an example concerning spectrophotometric determination of Co(II) and Cr(III) in solution. 22 factorial has been applied and the relationships between absorbances measured at 1=513 nm and 2=408 nm have been approximated by first degree polynomials. The error of analysis is discussed.
Die Anwendung der Theorie der statistischen Versuchsplanung auf die verallgemeinerte Standardadditionsmethode
Zusammenfassung Die Anwendung der Theorie der statistischen Versuchsplanung und empirischer polynomischer Modelle für die verallgemeinerte Standardadditionsmethode wird vorgeschlagen. Standardadditionen werden nach einem Versuchsplan, etwa einem 2sun-faktoriellen Versuchsplan, getätigt. Es ist einfach, die Konzentrationen der Analyten zu berechnen und die Fehleranalyse ist übersichtlich. Die Durchführung wird detailliert am Beispiel der spektrophotometrischen Bestimmung von Co (II) und Cr(III) in Lösung erklärt. Ein 22-faktorieller Versuchsplan wurde angewandt und die Zusammenhänge zwischen den gemessenen Extinktionen bei 1=513 nm und 2=408 nm werden durch Polynome ersten Grades approximiert. Die Fehleranalyse wird diskutiert.相似文献