Acta Physica Sinica -

THE GENERAL METHOD FOR SOLVING MAGNETIC CIRCUIT AND NON-LINEAR ELECTRIC CIRCUIT OF DIRECT CURRENT HOWEVER COMPLICATE

WANG SHIANG-YAWNG — 1959-03-20

Author(s): WANG SHIANG-YAWNG

In this paper is suggested the general method for solving the magnetic circuit however complicate of negligible leakage flux, which was unsolved before. The general method makes direct use of the n Kirchhoff's equations of the network with n branches, and is essentially an ingenious combination of the diagrammatical method with the "cut-and-try" method, the latter being so schemed as to yield the correct results quickly with some auxilliary curve plottings. The article deals with the theorems and procedure of solution of the network in detail.As the non-linear element in an electric circuit is analogous to a branch of the magnetic circuit, the general method suggested can bs adopted equally well to solve the complicated non-linear electric circuit containing any number of non-linear elements, which can be hardly solved by any other known method even with the aid of Thevenin theorem and other theorems of transformation of electric networks.

Acta Physica Sinica. 1959 15(3): 113-130. Published 1959-03-20

ON THE PROCESS OF THE PREPARATION OF NUCLEAR EMULSIONS N-2 and N-3

HO ZAH-WEI, LOU TSU-YING, SUN HAN-TCHENG — 1959-03-20

Author(s): HO ZAH-WEI, LOU TSU-YING, SUN HAN-TCHENG

This paper deals with some important problems on the process of preparing proton sensitive nuclear emulsion.By controlling the concentration of bromide ions during emulsification, the size of the silver halide grains is made quite uniform. In order to raise the sensitivity of emulsion, we select the optimum condition at the ripening stage and add the sensitizer "triethanolamine" before coating. Latent image fading is restricted by adding gold salts into the finished emulsion and the fog is minimized by purifying the photographic gelatin.After systematical investigation on the process of preparation, it is now possible to "produce proton sensitive nuclear emulsions with the same characteristics. They are about the same as those of "Ilford C2" emulsion for nuclear research.

Acta Physica Sinica. 1959 15(3): 131-138. Published 1959-03-20

METHODS OF PREPARATION AND CHARACTERISTICS OF NUCLEAR EMULSIONS

LOU TSU-YING, SUN HAN-TCHENG, LEU WEI-TCHANG, HO ZAH-WEI — 1959-03-20

Author(s): LOU TSU-YING, SUN HAN-TCHENG, LEU WEI-TCHANG, HO ZAH-WEI

Details are given for some kinds of nuclear emulsions which can be prepared by simple laboratory methods. The characteristics of these emulsions have been compared with Ilford nuclear emulsions. The properties of proton sensitive nuclear emulsions N-2, N-3 are about the same as. those of "Ilford C2". Nuclear emulsions for detecting thermal neutrons "N-2 loaded with boron or lithium" seem better than "Ilford C2 loaded with boron or lithium". The sensitivity of electron sensitive emulsion N-4 is of the same order as that of emulsion "никфи P" and "Ilford G5". The hypersensitized electron sensitive emulsion N-5 is also discussed.

Acta Physica Sinica. 1959 15(3): 139-144. Published 1959-03-20

НЕКОТОРЫ ВОПРОСЫ ФИЗИКИ ТРЕНИЯ И ИЗНОСА

1959-03-20

Author(s):

Acta Physica Sinica. 1959 15(3): 145-156. Published 1959-03-20

GROWTH OF NaCl CRYSTALS FROM SUBLIMED VAPOR

CHANG YUAN-LUNG — 1959-03-20

Author(s): CHANG YUAN-LUNG

By sublimation of NaCl crystals of high purity in vacuum at a temperature near its melting point single NaCl crystals of macroscopic size were grown at zones of somewhat lower temperatures. Oriented overgrowths up to 1 mm thick were obtained over the whole cleavage faces of the crystals, but the deposition was muchmore effective on the faees normal to the temperature gradient.The influence of zonal temperature differences and the geometric form of the substrate upon the size and orientation of the crystals have been investigated. The relative importance of faces observed was found of the following sequence: 100< 111<120<122<110. of these the form 122 has not been reported for NaCl crystals growing from the solution. But there is ample evidence from the present experiment that the dominance of 111 over 120 may not be as certain as obsreved for the crystals prepared from solution.In accord with the theory generally held, initial deposition was found to take place statistically more often at the corners of cube faces than elsewhere. New patterns of interpenetration growth and surface structures have been observed and there are features indicating layer growth and screw dislocation.Preliminary experiment was also made on evaporation of a cylindrical NaCl crystal resulting in the exposition of the faces (100) and (120).

Acta Physica Sinica. 1959 15(3): 157-166. Published 1959-03-20