Vol. 23, No. 4 (1974)
1974-02-20
CONTENT
1974, 23 (4): 1-14.
doi: 10.7498/aps.23.1-2
Abstract +
Starting from the principle of relativity and the local constancy of the light velocity, in this paper we establish a space-time model with the classical domain Dλ(1, 4). We discuss the kinematic effect in it and calculate the frequency shift of the spectral line, and also under the assumption of uniform distribution we compare our result with the observational data of the quasar N-Z relation. Our result shows that the large red shift in the extragalactic objects perhaps is not caused mainly by the Doppler effect, but to a large extent is a distance effect in the λ λ (1, 4) [its group of motion being SO (3,2)] is possibly a better model for large-scale space-time.
1974, 23 (4): 15-24.
doi: 10.7498/aps.23.15-2
Abstract +
The mathematical analysis for point-doping in zone melting has been given in detail. A series of general formulae of impurity concentration distribution along the ingot after point-doping zone melting has been derived. In this paper, within the range of our investigation, it is not at difficult, by means of these formulae, to obtain the impurity concentration distribution in an ingot after any number of passages of zone melting, without being restricted by the number of passages of zone melting and the number of doping points.As an example, the impurity concentration distribution after three passages of zone melting for the case of к = 0.35 and four doping points is specifically calculated. It is shown that, if the position and doping amount of each doping point are suitable, for an ingot of 21.5 melting zone lengths, the relative fluctuation of impurity concentration in 16 lengths may be less than ?3.0%.
1974, 23 (4): 25-39.
doi: 10.7498/aps.23.25
Abstract +
The relation between the theory of Yang-Mills fields and that of connections of principle bundles is established. It is proved that the new definition of the Yang-Mills field suggested by Yang is equivalent to the parallelism along a curve. The field equations proposed by various authors are discussed. A solution without singularity is given to Yang's field equations.
1974, 23 (4): 40-67.
doi: 10.7498/aps.23.40
Abstract +
We further generalize the composite field theory[1] to the case when basic field is spinor and derive the relevent formula in the straton model for the processes involving mesons. It is shown that the results obtained are valid for other models also.
1974, 23 (4): 68-74.
doi: 10.7498/aps.23.68
Abstract +
Internal friction measurements were made on commercial iron specimens containing various amounts of cerium and lanthanum (combined content: 0, 0.011, 0.026. 0.037, 0.075, 0.124%). For specimens thoroughly treated with wet-hydrogen to remove carbon and nitrogen impurities, the activation energy associated with the grain boundary internal friction peak was found to vary with the content of cerium and lanthanum. A maximum appears around the content of 0.03%. The maximum activation energy is 11.3×104 calories per mole and is about twice the value for iron free from cerium and lanthanum (6.4×104 calories per mole). For specimens loaded with carbon, the grain boundary internal friction peak was found to appear at a temperature 30℃ higher than that of the specimen free from cerium and lanthanum. The activation energy associated with the grain boundary peak was found to be 7.6×104 calories per mole (experimental error is within ±2000 calories per mole) and is approximately independent of the cerium and lanthanum content.Measurements on the Snoek peak associated with carbon in iron showed that the height of the peak decreases with an increase of the content of cerium and lanthanum, whereas the position of the peak remains unaltered as compared with that of iron specimen free from cerium and lanthanum.The cold-work internal friction peak of the original iron specimen containing carbon and nitrogen was found to appear around 230℃ (with the specimen cold-worked to 88% reduction in area), and this peak was considerably lowered with an increase of the cerium and lanthanum content. After the specimens were fully treated with wet-hydrogen and then loaded with nitrogen, the cold-work peak (with the specimen cold-worked to 88% reduction in area) was found to appear around 190℃. This peak was also considerably lowered with an increase of the cerium and lanthanum content.Preliminary discussions were made on the possible origins of the effect of the addition of rare earth elements on the three internal friction peaks (grain-boundary peak, Snoek peak, cold-work peak) of iron.
