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101.
Martin Macháček 《Journal of statistical physics》1987,47(5-6):949-952
We define mathematically a class of dynamical systems that exhibit relaxation corresponding to that observed in physical systems, and then show that this class is identical with the class ofK-mixing dynamical systems. 相似文献
102.
J. Kuriplach L. Lešták M. Rotter B. Sedlák M. Trhlík M. Finger T. Lešner J. Dupák P. Novák M. Vobecký 《Hyperfine Interactions》1987,34(1-4):339-342
First experimental results of160Tb nuclear orientation in yttrium single crystal matrix are described. The influence of external magnetic field in combination with the crystal field interaction is discussed. 相似文献
103.
In the framework of path integrals we present a solution to the Schrödinger equation for a free particle confined to the half-linex > 0. A solution in question corresponds to the boundary condition (/x) (0,t)= (0,t) where is a real constant. 相似文献
104.
The stochastic theory of the crystal growth is compared with the solution of the Stefan problem in the case of Sn solidification. It is shown that the stochastic theory gives the same results as the solution of the Stefan problem if kinetic processes at the solidification front are very rapid. 相似文献
105.
106.
M. Rotter B. Sedlák J. Englich P. Čížek M. Finger P. Malinský 《Czechoslovak Journal of Physics》1986,36(11):1331-1335
The results of NMR/ON measurements on56,57,60Co isotopes in iron are presented in the paper. To avoid the uncertainties caused by local demagnetizing field inhomogeneities the measurements on two cobalt isotopes in one sample have been carried out. The values of nuclear-factors ratios
57/
60=1·805(20),
60/
56 = 0·761(20),
56/
57 = 0·726(20) and hyperfme anomalies56
60 = –0·036(10),60
57 = 0·017(10) and57
56 = 0·018(10) have been calculated from the experimental results.Dedicated to the 30th anniversary of the Joint Institute for Nuclear Research. 相似文献
107.
108.
J. Brandštetr 《Journal of Thermal Analysis and Calorimetry》1981,21(2):357-365
A review of instruments for thermochemical (thermometric) solution analysis is given, including new types of isoperibol reaction of bomb calorimeters, the design of which can influence the future development of thermochemical measuring techniques. The new type of Dithermanal (Vaskut-EMG, Hungary, and Herrmann- Morris, France) controls the individual steps of the thermochemical analysis, adding memory and computing capabilities. Similar programming units with microprocessors for bomb and/or reaction calorimetry have been developed by Parr Comp. and Leco Comp. (USA). The latest modification of the Technicon flow analyzer permits on-line analysis of solid samples. For thermochemical titrations, the Sanda titrator (USA) and Vaskut automatic titrator (Hungary) are available. In the USA, the Tronac isothermal or isoperibol calorimeters are widely used. At the Technical University of Brno, ?SSR, smaller table instruments with a water-bath are applied for different modes of solution thermochemical analysis, and also for the reactions of solid samples in liquids. For the measurement of very small temperature differences, PTC thermistors are used. The possibilities of the future development of measuring techniques are outlined. 相似文献
109.
Summary A high molecular weight sodium hyaluronate isolated from rooster combs was degraded by ultrasonication. High-performance size exclusion chromatography allowed rapid and accurate determination of molecular weight parameters (Mz, Mw, Mn) and distributions. The time dependence of hyaluronan ultrasonication to the molecular characteristics of the polymer was investigated. A non-random nature of the degradation process was demonstrated and the reciprocal Mn value was found to be linearly proportional to the time of ultrasonication. 相似文献
110.
Unit cell parameters have been calculated from x-ray powder diffraction data of Mo2Br4
Py
4 (A), Mo2I4
Py
4 (B), Mo2I4
Pic
4 (C), Mo2(SCN)4
Py
4 (D) and Mo2(SCN)4
Pic
4 (E), A, B and C crystallize tetragonal. A witha=9,42,c=15,O2 Å; B witha=9,46,c=14,98 Å and C witha=9,66 andc=15,72 Å D and E crystallize orthorhombic. D witha=10,09,b=9,14,c=15,08 Å; E witha=10,22,b=9,41 andc=15,15 Å.Py=pyridine,Pic=4-methylpyridine. 相似文献