Vol. 16, No. 5 (1960)
1960-03-05
CONTENT
1960, 16 (5): 247-251.
doi: 10.7498/aps.16.247
Abstract +
The branching ratio of π+→e++v+r to π+→μ++v is calculated by standard perturbation method. The universal Fermi weak interaction of V-A type and a strong interaction proposed by Salam are assumed. The result does not contradict with the most recent experiment.
1960, 16 (5): 252-262.
doi: 10.7498/aps.16.252
Abstract +
Dispersion relations for pion production in pion-nucleon colHssions are discussed. The scattering amplitude is written in a form, in which the operators of nucleon field are extracted from the state vectors of initial and final state. The kinematies and symmetry, properties are worked out in detail and the contribution of bound state is evaluated.
1960, 16 (5): 263-271.
doi: 10.7498/aps.16.263
Abstract +
This paper described deformation and recrystallization in (110)[00l] single crystals of iron-silicon (3.25%) which reduction of thickness 5-50%. In the range of a reduction 2-16%, the slip planes ate (101), (101), (110) and (Tl0); and the twinning planes are (112) and (112). Which coincided satisfactorily with our explanation on the formation of cold-rolling textures in (110) [001] singe erystals of iron-silicon alloy.We observed that the position and growing process of recrystallized grains are difference between cold-rolling 35 % and 50 % with annealing treatment. The recrystalized grains of the former formed first at twinning boundary and preferred growth along the twinning boundary. But the latter may be formed by subgrain except forming at twinning boundary and near the deformation bands, and the preferred growth is not as apparent as former.
1960, 16 (5): 272-280.
doi: 10.7498/aps.16.272
Abstract +
Small quantities (0.1, 0.5 and 1.0 weight percent) of rare earth oxides (La2O3, CeO2, Sm2O3, Gd2O3) and Y2O3 were added to a square-loop Mg-Mn ferrite which contained some ZnO and CuO. The effect of these additions on the static hysteresis loop and the signal to noise ratio was investigated. The samples were prepared by the usual oxide method, sintered 2 hours in air at 1300℃ and quenched from l050℃ or 950℃. Preli-minary results showed that La2O3 or Gd2O3 increased the squareness ratio (B-Hm/2)/Bm and the signal to noise ratio (uV1)/(dV0). Furthermore, for a large number of cores, the distribution curve of (uV1)/(dV0) was shifted as a whole to higher values of (uV1)/(dV0). In contrast, CeO2, Sm2O3and Y2O3 additions did not show these effects. The saturation magnetization and the Curie point were not appreciably effected by the introduction of the rare earth oxides. The influence of the core size, the quenching temperature as well as the content of rare earth oxides on the squareness ratio and the signal to noise ratio was also noted.
1960, 16 (5): 281-288.
doi: 10.7498/aps.16.281
Abstract +
The yttrium-ytterbium (Y-Yb) garnet system Y3-xYbxFe3O12 was investigated at the compositions for which x=0, 0.75, 1.50, 2.25 and 3.00. The samples were prepared by the co-precipitation method and sintered 7 hours in oxygen atmosphere at 1350℃ or 1400℃. Lattice constants and theoretical densities were determined from X-ray diffraction data. It was found that the whole system consisted of a single phase with the garnet structure, and the lattice constant decreased linearly from 12.371? (Y3Fe5O12) to 12.297? (Yb3Fe5O12). The static hysteresis loop, the initial permeability at 500 Kc, the saturation magnetization between liquid-air temperature to the Curie point and the magnetic spectrum between 500 Mc and 3000 Mc were observed as a function of compositions. It was found that all the samples had high bulk densities ( > 90 % theoretical densities) and high resistivities (109—1010ohm-cm), and that the saturation magnetization Vs temperature curves had positive slopes at 10W temperature for x ≥ 1.50.
1960, 16 (5): 289-298.
doi: 10.7498/aps.16.289
Abstract +
The Bethe-Weiss method in the statistical theory of Heisenberg ferromagnetism is generalized and applied to the case of subtitutional solid solutions of random distribution. Calculations are carried out for binary solutions containing magnetic atoms of spin 1/2 and nonmagnetic ones. The Curie temperature v.s. composition and the paramagnetic susceptibility v.s. temperature curves are obtained for simple and body-centered cubic lattices. The degree of magnetic short-range order at the Curie point becomes higher as the concentration of non-magnetic atoms increases. The results are qualitatively applicable to solutions of two different kinds of magnetic atoms. It is also concluded that the method gives an useful approximation only for higher concentrations of magnetic atoms.
1960, 16 (5): 299-304.
doi: 10.7498/aps.16.299
Abstract +
The relative probability of the radioative decay of π-meson to that of π-μ decay is calculated, assuming a universal Fermi interaction of V-A type. Terms in addition to those of usual gauge invariant treatment are calculated with perturbation theory. The result does not contradict the experiment.
