The equation expressing the relation between apparent dielectric constant and moisture content of paper, pulp and cloth has been worked out by a few investigators in different forms. Among them, Akkar and Hardacker's equation, which is based on Clausius-Mosotti's equation, was found not to agree with experiment at high moisture region, the probable cause of which is that the equation was derived by assuming the dielectric constant of hypothetical paper to be solely composed of that of cellulose and water neglecting that of air and also by ignoring the polarity of water molecule. By assuming cloth to be composed of cellulose, water and air, the authors obtained an equation for the cloth by applying Debye's and FrShlich's equations to dielectric constant of water and then by combining Clausius-Mosotti's equation. Experiments on serge and muslin made of viscose span rayon showed good agreement with the equation.
A composit junction model is presented for theorizing the characteristics of p-n junction. The model has regions of graded and uniform distributions of impurity, thereby the parameters concerned are the concentration gradient a and the resistivity ρ of the materials. Observed values of the breakdown voltage VB and the barrier capacitance Cr of silicon p-n junctions of varying a and ρ (ρn_??_0.1_??_20 Ωcm) are found in good agreement with the values that are expected from the theory derived from the model. The deviation from the theory of well known simple model is successfully explained especially in the higher resistivity region. For a given resistivity, Vii increases gradually with the depth of diffusion Xj at first, then varies with its square root above the critical value of Xj as predicted by the author's theory. Further, for given a and ρ, CT decreases with the third root of the voltage at low reverse voltages applied, and at high reverse voltages, it decreases as though a much higher voltage had been applied, varying nearly in accordance with the square root law similar to She case of an abrupt junction.
By the use of microwave discharge in air, successful detection of signals is made, the frequencies of which are integral multiples of the applied frequency. Output power of each harmonic component is a function of discharge gap length, pressure and circuit condition of the discharge cavity. The output power becomes maximum around a particular pl value corresponding to Vs, -minimum of pl-V s, curve where p is the pressure, l the gap length and Vs, the breakdown voltage. Any particular harmonic output can be selectively multiplied by adjusting the circuit condition. This new method of frequency multiplication has characteristics in that (1) a large power input can be consumed, (2) the electrode dimensions can be much larger than those of conventional type of microwave generator and (3) the efficiency of frequency conversion is very high. There is a great possibility of this being utilized for high power frequency multiplication especially in microwave region. Application of this principle to millimeter wave generation is also considered possible in which effective display of the characteristics might be expected.
In order to study the initial mechanism of sintering of an alloy, a few spherical beads of 30-70 Au-Ag alloy (which is prealloyed) are hot-pressed and sintered by the same method as described in the former report1)2). The diameters of beads tested are 1.35, 0.85 and 0.45 mm. Forlexample, the beads (0.85mm in dia.) are sintered at 453°K for 5 minutes under a load of 3.5 kg or at 1193°K for 5 minutes under no load. These temperatures are 35 and 94% of the melting point of this alloy respectively. ectivel The value of _??_where W is the load, 2r the diameter of bead and t the sintering time, changes with the lowest sintering temperature Ts. In the case of 0.85 mm in diamter, ξ has a maximum value in the range of recrystallization temperature of this alloy (200°_??_500°C). The ratio of the diameter of adhered area between two beads to the diameter of the bead is found to take a certain value independent of the dimension of the bead, but it becomes larger with the load. For example, it is about 5.5% under no load, but about 18% under a load of 100g. The activation energy to effect sintering between two beads changes with the lowest sintering temperature. In the case of 0.85 mm in diameter, it becomes smaller with the lowest sintering temperature, but has a minimum value within the range of recrystallization temperature and then it becomes larger. Its minimum value is about 23 kcal/mol and the largest value is 73 kcal/mol., These values are respectively about 1/2 and 6.5 times as large as the activation energies of self-diffusion of gold (44.1 kcal/mol) and silver (44.7 kcal/mol) in 50-50 Au-Ag alloy4).
The change in absorption and velocity of pulsed ultrasonic waves (6.6 Mc/s) in process of gelation has been studied for polyethylene solutions in benzene and xylene as well as aqueous solutions of gelatin and starch. The absorption is found to depend strongly on cooling rate. In the case of polyethylene, the absorption (excess absorption over the absorption by pure solvent) occurs both at rapid and slow rates of cooling, the value being larger in the former case than in the latter. In the cases of gelatin and starch the absorption takes place only at rapid cooling. In all cases the absorption can be attributed to scattering of sound waves by inhomogeneity in gel. The absorption tends to vanish in several ten minutes after gelation, indicating the diminution of inhomogeneity. Only for starch gel, the absorption again increases gradually in several hours, presumably owing to syneresis. No anomaly was found in sound velocity in course of gelation.
In order to study the segregation or crystal deformation in crystallites in polycrystalline specimens, a new type X-ray camera has been made. The camera has a rotating cylinder, at one end of which the specimen plate is fixed. The slit system of this camera consists of two pin-holes, 0.03 mmø each, fixed in the camera body apart 0.38mm from the rotating axis of the specimen. The film cassette is fixed on the camera body parallel to the specimen plate. Then, as the specimen is rotated, irradiated point on the specimen moves from place to place continuously along a circle of 0.38 mm radius. Diffraction patterns appear in several arc lines, and by measuring the shape and sharpness of these diffracted arc lines, irregularities along one grain boundary to the next of the crystallite can be accurately found. The camera has been tested for a pure Al plate (grain size 3mmø) and a Cu-Be alloy plate (grain size 1 mmø, age-hardened) with satisfactory results.
From the measurement of line profile of X-Ray diffraction pattern by electrodeposited nickel films, “true line profile” ƒ(x) is found by using line profile of 5 μ nickel powder as the pure instrumental broadening. Each specimen is irradiated with CuKa doublet ray 40 kV, 15 mA and intensity is measured by G-M counter tube according to the so called “fixed count method”. Fourier analysis, worked out by Stokes, is used to calculate ƒ(x), and A(t)-t curve is plotted according to the method of Warren et al. for the purpose of separating grain size broadening from distortion broadening. The results are summerized as follows. (1) Apparent asymmetry is eliminated from the line profile of electrodeposited nickel films, but it could not be made clear whether peak shift is intrinsic or not. (2) Adsorption of hydrogen is more marked on (111) than on (200) in the case of luster nickel film, and grain growth of  is hindered as the result of adsorption of addition reagent. (3) Apparent grain lengths, ε111 and ε200, are estimated as 407 Å for non luster film , 310Å for luster film  and 177Å for luster film .
Calibration of reference thermocouple of a high temperature X-ray diffraction camera is made by nearly the same method as used in the author's former report. Amount of temperature deviation is calculated quantitatively as a function of temperature under various conditions of thermocouple wires and the specimen holder rod, which are their thickness, length, emissivity, thermal conductivity, relative situation in the furnace etc. A new coefficient δ is introduced in the calculation in order to treat the size effect of the thermocouple head. The so-called gap effect is also considered. At low temperatures, the temperature deviation is mainly due to thermal flow through thermocouple wires, while, at high temperatures, the gap effect becomes predominant. Maximum temperature deviation occurs, at about 450°K in vacuum and at about 650°K in air if the gap effect is neglected. Very large deviations increasing with temperature are observed, and the calibration curves are strongly affected by the relative situation of the thermocouple head and the specimen when the gap effect is large. Temperature distribution on the specimen holder rod is also analysed. The results are compared with experimental data and discussion is made for obtaining favorable conditions to minimize the temperature deviation.
Orientations of photolytic silver in silver chloride crystals grown from solution and melt are studied by electron diffraction method. The orientations are classified by various means of photolysis and compared with the case of silver bromide. Main features of the silver separation of silver chloride do not differ from those of silver bromide. The various orientations are explained by such factors as (a) fitness of lattice spacings, (b) trapping by lattice irregularities and (c) surface tension effects, and also surface topography and chemical reaction planes. Energy level diagram proposed for silver bromide is used also for silver chloride, and the ability of controlling the structure sensitive properties of silver halide crystals is discussed.
Adsorbed structure of various cyanine sensitizing dyes on silver bromide is studied by electron diffraction method. Molecules of cyanine iodide alone are adsorbed in multimolecular layer. Adsorbed cyanine iodides are classified into two types, one is of well-defined diffraction patterns and the other of haloes. When the dyes are washed off by ethyl or buthylalcohol, only the pattern of silver iodide appears indicating that silver bromide changes into silver iodide by the dyes and also that the dyes are adsorbed not on silver bromide but on silver iodide. The well-defined pattern of the dyes closely resembles in structure to that of silver iodide and the lattice constant of the dyes differs from that of silver iodide by only 2_??_3%. By using single crystals of silver iodide made from melt, it is shown that the adsorption of the dyes on (10, 0) surface of silver iodide is stable and traces of orientation of the adsorbed dyes on (00, 1) surface are similar to those on (10, 0). Hexagonal structure of the dyes gives no indices of C axis. Hence, the dyes are adsorbed with their side spacing equaling the atomic row spacing of 4.59 Å of the substrate. This means a tilting of about 60° of the dye molecules which are of about 4 Å in thickness.
Adsorbed structure of cyanine bromide and cyanine chloride sensitizing dyes on silver bromide and silver chloride single crystals made from melt is studied by electron diffraction method. The dyes are adsorbed in multimolecular layer from alcohol or aquous solutions by vaporization method. The dyes have proper side spacings determined likely by their thickness and adsorption angle to the substrate, and the adsorption becomes regular if the dye side spacing and the spacing of atomic row in the substrate crystal surface are equal. If the adsorption activity of the crystal surface is strong, the dye side spacing can be somewhat modified, but if it is weak, the orientation becomes fiberous, and if still weaker, the orientation will be random. The dye lb on silver bromide has a proper side spacing of about 6 Å, and is regularly adsorbed by atomic row spacing of 5.75 Å of the substrate, therefore the dye having thickness, of about 3.5 Å is adsorbed with an angle of about 40° to the substrate. The dye XXIb has a proper side spacing of about 4 Å, and is regularly adsorbed by atomic row spacing of 4.06 Å, with an angle of about 60°. The dye VIIIc on silver chloride has a proper side spacing of about 4.3 Å, and shows either fiberous orientation or self crystal structure.