1. Introduction. 2. Method to Produce Bubbles. 3. Forces Between Two Bubbles. 4. Dislocation. 5. Grain Boundary. 6. Dynamical Behaviour of Grain Boundary. 7. Recrystallization. 8. Three. Dimentional Assemblages. 9. Diffraction Patterns Produced by Bubble Rafts. Crystal structures and effects represented in rafts of soap bubbles, such as dislocations, grain boundaries and mobility of grain boundaries, recrystallization are reviewed by the photographs almost taken in the author's laboratory. Especially the mechanism of the varying nature of the grain boundary with the angle of disorientation is discussed.
A portable stroboscope, using a simple cold cathode fluorescent tubeas the light source, was made and its electrical and optical properties were measured. It has following advantages compared to those made as yet, (1) upper limit of the stroboscopic frequency is high, (2) the light source tube has asimple structure and the vacuum tubes used in the electri-cal circuit are popular radio receiving tubes, (3) the life of the light source tube is long, (4) the color of the stroboscopic light is approximately white because of using fluorescent material, (5) the light intensity is, strong enough to take photograph in a dark room.
The rates of thermal decomposition of seven oils in a evacuating system similar to the operation of the glass diffusion pump were measured in the neighbourhood of their operating temperatures. The rate of the evolution of decomposed gases is represented as the rate of flow (S×ΔP) which is the product of the pumping speed and the pressure rise at the ionization gauge. It becomes evident that the rate of reaction and its initiation owe to the small concentration of unstable substances in the oils. This conclusion is strongly assitingin the previous discussion on the ultimate pressure of oil diffusion pump.
Though it is not yet trade clear what is the resistance which acts on a car rolling on sand, the problem of the car resistance should be induced from that of the wheels. From the results of some amount of experiments carried outon a single wheel, we succeeded to get an outline of the resistance problem of cars progressing on sand in general. In the experiments the vertical and horizontal components of the resistance which represents the relations between the magnitude and the direction were measured as function of the depth of sinking in sand and by the use of that relation, the relations between the components were determined. Additionally, the dependency of the above relations on the velocity of the car, the size of the sand particles and the packing state of sand were investigated. On the other hand, the revolution of the wheels depends on various conditions and there exists some amount of slip between the wheel and the sand. Experiments carried out on the slip problem are also reported.1)
The judgment of color in the colorant industrys have used the visualcolor matching generally. The practical technique that is low-cost, simple and speedy, have not been found. The spectrophotometry is most accurate of the various measurements of color. Therefore, it was tried to study as follow. 1) The spectral energy differences are looked for both colors to compare. 2) The differences are integrated by CIE tristimulus calculation. 3) If both colors are equal, the answer must be zero. Moreover, the factor of Color differences are looked for this method approximately, and the testing time may be shortened by which the number of times of the measurements are reduced. Now, thismethod igtestibg on our factory.
The ZnS phosphors, into which were added the heavy metal Pb, Sn, Sb, Bi, or Mn as first activator and a small amount of copper as second activator, have been prepared and their spectral sensitivity for stimulation or quenching ofphosphorescence upon irradiation with IR invest gated. According to the experimental results the Pb-activated phosphors and some Mn-activated one showed stimulation, and the others were of quenched type. All the phosphors had the two peaks of sensitivity at the wave-lengths 1.1-1.5μ and 0.7-0.9 μ and the general features of the curves were almost similar. The Mn-activated phosphors were of stimulated or quenched type, and their type was determined by concentration of Mn-activator. Further, from these results is presented a comparatively simple mechanism that will be able to cover the most important and general behaviorof infrared responcibility after ultraviolet exitation.