In X-ray microanalysis, when elements widely different in atomic number are present in a specimen or when absorption and fluorescence effects within the specimen are significant, correct mass concentration of a given element in the specimen is not obtained directly from the relative intensity which is the ratio of the intensity of characteristic emission of the element from the specimen to that from a specimen of pure element. In this paper the principles and methods of correction to obtain true mass concentration proposed by many workers are compared with one another and discussed, and procedures and data necessary for the correction are given and applied to experimental data of some alloys. In comparison with values obtained by chemical analysis, the corrected values have yet errors of 1 to 2%. For higher accuracy, accurate values of mass absorption coefficient of various elements for various X-ray radiations should be made known. Some errors that arise in the course of experimental procedure are also discussed.
The dislocation damping in cold worked α-iron is studied with a torsion pendulum. The component (QH-1), which is dependent on strain amplitude of the dislocation damping, is proportional to strain amplitude and vanishes at the first stage of recovery (-40_??_-20°C). This recovery seems to be due to a thermally activated rearrangement of unstable dislocations. The component (QI-1), which is independent of strain amplitude ;and has a weak dependence on temperature, disappears at the second stage of recovery (20_??_40°C) by pinning of dislocations with interstitial impurities (carbon and/or nitrogen). Experimental results seem to be explicable on the basis of a static hysteresis model taking account of thermal unpinning of dislocations from impurities.
Thin layers of antimony triselenide on Nesa glass substrate are prepared by vacuum evaporation. The optical transmission, spectral sensitivity and response speed of the photoconductivity are measured. Dark resistance of the layer is 109 ohm-cm; it decreases to 1/2_??_1/3 by illumination (100 lux) of an incandescent lamp. The photoconductive maxima lie in the region of 820_??_900mμ; they are observed to depend on the polarity of applied electric field. The deposited layer on the substrate held at temperature lower than 100°C is amorphous, but the layer deposited at higher temperatures has a decreasing resistance due to crystallization.
Experimental study is made on pn junctions prepared by diffusing zinc into n-type GaAs. Light-modulation and its spectral dependence are examined on two kinds of samples. When the light by injection luminescence is passed through the modulating junction normal to its plane, modulation factor is 2.7% at room temperature and 3.3% at liquid nitrogen temperature. Effective absorption coefficient of depletion layer of the modulating junction is found to be 103cm-1. And when the light is passed through the modulating junction parallel to its plane, 2% is obtained at room temperature. It is presumed that the modulation factor by passing the light normal to the junction plane can not be increased far greater than the value so far obtained but can be increased even up to 100% by passing the light parallel to it if a fine beam of light is focused on the junction.
Pressure and temperature measurements with a modified girdle type high pressure apparatus are studied. The applied load required to obtain the transitions of bismuth, thallium and barium is found to depend on internal configuration of sample holder and some pressure distribution is observed in the reaction vessel. Pyrophyllite powder gasket is proved to be a good substitute for usual one produced from block pyrophyllite. Method of insertion of thermocouple into the reaction vessel is studied. No pressure correction is found necessary for electromotive force of 6% RhPt_??_30% RhPt thermocouples. The applied electric power required to obtain a constant temperature increases with the pressure but approaches to a constant value.
Concerning the roughness curve, the relation between distribution function of fineness and Abbott's bearing curve is discussed. When the roughness curve is measured in a form of voltage wave, the probability density function of fineness at level X is expressed as Mn(Z)=n(Z)-An(1)(Z)+Bn(2)(Z)-Cn(3)(Z)+Dn(4)(Z)……, where Z=(X-μx)/σx (μx: mean; σx2: variance) and n(Z) is a normal distribution function. This theoretical derivation is experimentally verified for (a) high correlations between height and slope (b) relation between height and fineness distributions.