bluuebunny/crossref_metadata_2025 huggingface dataset:
Oxidation Rate and Phase Diagram of Mu-Zn Ferrite Determined from the Cation Diffusion Coefficient
Authors: Ogawa Seiya
Published: November 2005

Oxidation rate of Mn-Zn ferrite, which means the rate of change in oxygen content in spinel phase, was determined from the diffusion coefficient of 59Fe, by assuming that the diffusion coefficient was proportional to the cation vacancy density, i.e., the excess oxygen content. Volume oxidation rate and grain boundary oxidation rate are expressed by coefficients having the same dimension as the diffusion coefficient, and measured respectively from the experiments on a single-crystal and a polycrystal. The oxidation process is well expressed by the familiar “parabolic law.” The parabolic law constant obtained by the latest investigation corresponded to that by the weight gain technique.
Phase diagram of Mn-Zn ferrite–hematite–oxygen system was also determined by the behavior of the diffusion coefficient of 59Fe. This method of determining phase boundaries seems easier and more accurate than any other method utilized.
Electron Beam Extraction from INS AG Synchrotron. Part II. Experiment
Authors: Huke Kazuo , Kawasaki Sunao , Yamakawa Tatsuya , Yamaguchi Seitaro , Fukunaga Kiyoji , Kokame Jun , Yamashita Sukeaki , Yanabu Takuji
Published: November 2005

The electron beam has been extracted from the INS 750 MeV AG synchrotron. A Piccioni scheme was applied and the extraction efficiency obtained was 10% at the electron energy of 540 MeV and 5% at 700 MeV. The behaviour of the beam inside and outside of the synchrotron was studied in comparison with the theoretical analysis. The pulse duration of the extracted beam could be extended to the order of 700 µs without any difficulty for the 21.5 cps operation of the synchrotron.
Spectral Emissivity of Silicon
Authors: Satō Tsutomu
Published: November 2005

The emissivity of silicon was observed in the spectral region from 0.4 to 15 µ at various temperatures from 340°K to 1070°K by using two n-type specimens with the resistivity of 15 ohm-cm and 7×10-3ohm-cm at 300°K, respectively. The thermal radiation of silicon consists of three types due to band-to-band transition, free carriers and lattice vibration. It was made clear from the emissivity measurement that, in a pure specimen, the radiation due to lattice vibration is conspicuous at low temperatures, while that due to free carriers is predominant at higher temperatures, and that, in a doped specimen, the radiation due to free carriers is predominant even at low temperatures. The observed emissivity is close to the theoretical formula represented by the refractive indexnand the extinction coefficientk. The temperature dependence ofnandkis shown and a brief discussion is also added.
Steady State Properties of a Collision-Free, Cylindrical Plasma Injected in Longitudinal Magnetic Field
Authors: Okuda Takayoshi
Published: November 2005

Discussions will be given to clarify the steady state properties of a collision-free, cylindrical plasma of zero temperature in the presence of longitudinal magnetic field, with the aim of studying injected or synthesized plasma. In the analysis, the author proposes a new picture that the space charge field arising from inequality of charge density between the electron and ion may control the radial velocities of the electron and ion to satisfy a condition imposed on the total radial current density. The most realistic condition is such that the total current density is equal to zero. The present paper deals first with the potential and kinetic energies or velocities as a function of radial coordinate for homogeneous plasmas. Secondly, the collection of charged particles on a cylindrical electrode which is parallel to the direction of the magnetic field, is discussed. The third is concerned with the steady transient time and the focusing or spreading.
Determination of Radial Variation of Plasma Electron Density by Plasma Resonator
Authors: Akao Yasuo , Ida Yoshio
Published: November 2005

We have proposed, in our previous paper, a method for determining the plasma density utilizing the resonances of surface waves. A recognizable discrepancy between the densities determined from the symmetric mode resonances and those from the dipolar was pointed out. In this paper, the effect of radial profile of plasma density, as one of the possible reasons for this discrepancy, is examined and is found to be the most important. The effect, in turn, seems to offer an useful method to estimate experimentally the radial distribution of plasma density.
Charge Transport Phenomena in MOS System
Authors: Ohwada Atsushi
Published: November 2005

Drift phenomena of positive charges, which are induced by “hydrogen heating” in silicon dioxide, have been investigated. A new experimental method, in MOS transistor structure and discussions on the results are given. It is found (1) that the drift of the charge species occurs under externally applied field with an activation energy of 0.31 [eV], (2) that in silicon dioxide, the positive charge is bound in a potential well, which is “wall-like” in the vicinity of the metal-oxide interface and “slope-like” in the vicinity of the silicon-oxide interface, (3) that there is a potential minimum or “pocket” in front of the "wall-like" boundary, and (4) that the drift current is proportional to the square or higher powers of applied voltage, but the mechanism is not yet clear.
X-Ray Study on the Phase Transition of NaNO2
Authors: Hoshino Sadao , Motegi Hiroshi
Published: November 2005

The precise temperature dependence of x-ray diffraction effects near the transition temperature of ferroelectric NaNO2 crystal has been examined. The satellite reflections, 1±σ 5 0, start to appear at T

s
, 0.2°C below the well-known first-order transition point T

t
. Marked asymmetry of the satellite reflections was sometimes observed when a multi-domain crystal was measured. The period of the sinusoidal modulation along the a-axis varies from 10.3 a
0 to 8.4 a
0 with increasing temperature. The effect of a d. c. external field along the b-axis on the x-ray diffraction effect was also examined. The experimental evidence indicates the presence of a new phase between T

s
and T

t
. Some thermodynamical calculations for the phase transition of NaNO2 were carried out. To explain the intensity asymmetry of the satellite reflections the diffraction effect for a distorted crystal was also calculated.
Applications of the Marechal Method of Aberration Balancing. III. Extension to Seventh- and Ninth-Order Aberrations
Authors: Asakura Toshimitsu , Nagai Shohei
Published: November 2005

The Maréchal method of aberration balancing was successfully applied to spherical and parabolic reflectors and to various types of a single thin lens in the previous papers [Japan. J. appl. Phys. 5 (1966) 310 and 924]. In these papers, the third- and fifth-order aberrations only were taken into account so that the results obtained were limited to certain areas of field angles and F-numbers. The present paper extends the previous theory up to the seventh- and ninth-order aberrations. A spherical reflector is treated as a specific example and the results obtained are compared with those in one of the previous papers. The effectiveness of the present method is discussed and it is concluded that the use of the aberration terms up to the seventh-order is sufficient when a wide field angle is taken into considerations.
Fine Faults and Crystal Structures of Precipitates in Fe-Mo and Fe-W Alloys
Authors: Yagisawa Kōhei , Fujita Hiroshi
Published: November 2005

To investigate crystal structure and two-dimensional faults of the precipitates in Fe-Mo alloys, electron microscopic method was used. The crystal structure of the precipitates in Fe-Mo alloys aged above 1000°C was found to be rhombohedral, while it was generally hexagonal in the alloys aged bellow 900°C. Both kinds of precipitates were formed in approximately the same amount when aged at 940°C. The precipitates of both structures were found to have numerous two-dimensional faults. The faults were found on {00.1}hex, {10.1}hex and {10.0}hex planes in the precipitates of the hexagonal structure and on {111}rhomb and {100}rhomb planes in the precipitates of the rhombohedral structure. In the hexagonal precipitates in the Fe-W alloy aged at 950°C, faults were observed also on {00.1}hex and {10.1}hex planes.
Analysis of Autostabilized Light Modulator at Microwave Frequency
Authors: Nomura Sadao
Published: November 2005

The autostabilized light modulator at microwave frequency is analyzed by considering its resonance frequency shift. This analysis is based on thermal effects by heat produced in the modulator crystal by the microwave power and heat transfer from the crystal to an ambient medium. It is found that as long as the crystal temperature T does not exceed the transition temperature T

c
of the crystal the state will be stable and the stability of the modulator is determined by the temperature dependence of dielectric constant and loss tangent of the crystal.
The operation of the autostabilized modulator was examined by using an ADP crystal at 7GHz. This modulator is applied to the light transmission of video signals and the very successful results are obtained without any adjustments for a few days operation.
Studies on Etch Patterns of Barium Fluoride Single Crystals
Authors: Patel A. R. , Singh R. P.
Published: November 2005

By etching cleavage faces of synthetic barium fluoride crystals in nitric acid of a particular concentration, pits of different shapes and orientations have been produced on the same face. Correspondence in shapes and orientations of pits have been observed on matched pairs. It has been shown that the etch pits nucleate at the sites of dislocations. The inclinations of the dislocation lines have been calculated. The different shapes and orientations of the pits have been attributed to local changes in the structure of the crystal. Trisecting-Rows of etch pits have been observed on the two sides of thin flakes. It is observed that the pit density in one arm equals the sum of the pit densities in the remaining two arms. It is, therefore, conjectured that the rows of pits represent probably the small angle tilt boundaries in the crystal.
Improvement of Shock Wave Generation in a T-Tube
Authors: Fukuda Kuniya , Okasaka Rei , Fujimoto Takashi
Published: November 2005

In order to eliminate complex structure which is often found in shock wave region in a T-tube, three types of modifications were tried on an ordinary T-tube; (i) converging test section of the T-tube, (ii) application of a strong magnetic field to primary shock, and (iii) L-shape electrodes. In each case the behaviors of driving discharge plasma and the shock wave trajectories in front of a reflector plate were observed with a streak camera. In the experiment with an ordinary T-tube, discharge plasma was separated away from the electrodes at an early time in the first half cycle of discharge and this gave rise to the complex structure in shock wave region. In the experiment with the L-shape electrodes the complex structure was completely eliminated and the turbulence in the discharge plasma was suppressed to a considerable extent.
Solid-Solid Diffusion of Boron in Silicon Using Reactive Sputtering
Authors: Nagano Katuto , Iwauchi Shigeki , Tanaka Toshio
Published: November 2005

An investigation on the solid-solid diffusion of boron into silicon from doped oxide layer deposited by the reactive sputtering method is reported here. The surface concentrations are controlled over a wide range of low concentrations of from 1015 atoms cm-3 to 1017 atoms cm-3 and are almost independent of the diffusion temperatures and diffusion times.
The diffusion profile obeys mostly the complementary error function and the diffusion coefficient obtained is expressed as D=0.15exp
(-4.25(eV)/k
T) cm2 sec-1 at a concentration of about 1016 atoms cm-3 over a range of temperature of 1100°C to 1270°C. This value is smaller than those observed at high concentrations. Furthermore the surface concentrations depend linearly on the target concentrations.
Radiation from Moving Charge Train
Authors: Hirakawa Hiromasa
Published: November 2005

The radiation power received by an antenna aiming at a moving train of density-modulated charge is calculated. The fact that a certain amount of energy is received in this way should not mean that a moving charge radiates energy in free open space. This point is discussed in connection with the emission of Čerenkov radiation in uniform medium.
Fluid Layer Heated from Above II
Authors: Banerjee Mihir B. , Agrawal S. C.
Published: November 2005

The present paper investigates the stability of an inviscid fluid of small thermometric conductivity confined between two rigid horizontal parallel planes under the action of a uniform nonadverse temperature gradient while the fluid has a general streaming which depends only on the vertical coordinate z. The main results established in the paper are as follows:
It is shown that,
(a) The phase velocity of any arbitrary unstable or neutral wave must lie between the maximum and minimum of the streaming velocity.
(b) Principle of exchange of stabilities cannot be satisfied for velocity distributions which do not vanish anywhere in the flow domain.
(c) The complex wave velocity of an arbitrary unstable wave is shown to lie inside a rectangle for all a

x
1/2 and further a sufficient condition of stability is also given.
The 1/f Noise MOS Transistors
Authors: Tanaka Toshio , Nagano Katsuto , Nameki Naohiro
Published: November 2005

The low-frequency noise characteristics of MOS transistors with SiO2 films formed by reactive sputtering as gate insulators were investigated. An attempt is made to analyze the characteristics on the basis of the tunneling model. Reasonable agreement of the experimental result with the theorectical characteristics is found. Some informations on the noise generation centers are obtained.
Orthonormal Expansion of the Aberration Difference Function and Its Application to Image Evaluation
Authors: Sumita Haruki
Published: November 2005

Method of orthonormal expansion of aberration function is applied to the evaluation of the normalized image contrast M introduced by H. H. Hopkins, the decrease of which is proportional to the variance of the wave aberration difference function V over the domain S common to the two pupils displaced relative to each other. The difference function V is expanded in terms of Zernike's circle polynomials, the domain S being approximated by an ellipse fitted to S. The orthogonal coefficients of V are derived from a linear transformation of the orthogonal coefficients of wave aberration expanded over the pupil domain. A general formula of this transformation matrix is presented. A method of calculating the normalized image contrast M is described in terms of orthonormalized aberrations together with some numerical examples.
Epitaxial Growth of Silicon Films Evaporated on Sapphire
Authors: Yasuda Yukio , Ohmura Yamichi
Published: November 2005

Single-crystal films of silicon with good structural and electrical properties were successfully obtained on (000, 1) sapphire substrates by evaporation in a vacuum of about 2×10-6torr. Silicon was evaporated at a high deposition rate of 1500 Å/min, using a specially-designed electron bombardment apparatus. The growth process was investigated by reflection electron diffraction and replica techniques. The initial deposits contain four preferred orientations, all with (111) parallel to the substrate surface. Upon further deposition, one of the four orientations develops and a single-crystal film is eventually formed at a film thickness of about 800 Å. It is found that the recrystallization effect occurring on early coalescence of nuclei is essential to the growth of single-crystal films. Electrical properties were measured for the films, 0.7 to 6.1 µm thick. With increasing film thickness, carrier concentration decreases from 1017to 1016holes/cm3and Hall mobility increases up to 250 cm2/V·sec.
A Single Channel Pulse Height Analyzer of Gain Sweep Type
Authors: Takeuchi Satoshi , Nishino Osamu
Published: November 2005

Design and performance of a single channel pulse height analyzer of gain sweep type are described. The analyzer has a constant fractional channel width. The amplifier gain is varied discretely by a precision attenuator. When automatic operation of the analyzer is intended, pulses coming from a differential discriminator are counted by a storage counter and the dc output at the end of a cycle is held constant in the analog memory in the next cycle for the recorder display. Thus the spectrum is recorded in the histogram form.
The Determination of the Exchange Energy and the Effective Field of a Ferromagnet in the Neighborhood of the Curie Temperature
Authors: Korn J.
Published: November 2005

Equations with and without an external magnetic field were derived by using the Bethe-Peierls-Weiss method for the exchange energy and the effective field for iron. The numerical values for both the exchange energy and the effective field were obtained in the neighborhood of the Curie temperature. It was found that the external magnetic field does influence the exchange energy, and the critical point of the exchange energy at the Curie temperature vanishes if an external magnetic field is applied.
Experiment on the Evaluation of Metal-Semiconductor Schottky Barriers
Authors: Kano Gota
Published: November 2005

The forward voltage dependence of the “n” value, carrier storage effects and the excess noise, were measured for “ideal” Schottky barriers and “non ideal” Schottky barriers. The experimental results of “non ideal” Schottky barriers were explained by assuming the effects of the interfacial layer and the effects of donor surface states. The discussions made in this paper can be extended to the general evaluation of the Schottky barriers.
X-Ray Topographic Observation of Copper Whisker Crystals
Authors: Nittono Osamu , Nagakura Sigemaro
Published: November 2005

Copper whisker crystals, carefully grown from cuprous iodide by vapour reduction, were studied by means of x-ray topography and optical microscopy. About 50 whisker crystals with growth orientations [001], [110] and [111] were examined in a thickness range from 10 to 80 µ. None of them contained an axial dislocation. The same was true for kinked and spiral whisker crystals. The whisker crystals are in a high degree of perfection even at the thickness of 80 µ, although some of them contained lattice defects introduced accidentally during the growth. Results obtained indicate that copper whisker crystals do not grow by the growth mechanism, in which an axial screw dislocation plays an important role. There is a contrast change at the tip of the whisker crystal. Impurities at the tip may take part in the growth.
Preparation and Properties of BeO Thin Films
Authors: Nagai Haruo
Published: November 2005

BeO thin films have been prepared by hydrolysis of BeCl2 in the temperature range 690°C to 1200°C, and studied by reflection electron diffraction. The films are found to be apt to take a fiber structure orientating c-axis vertically to the substrate. It has been observed that one of these films was epitaxially grown on single crystal Si substrate. The infrared spectra of orientated films have been studied in the range 400 cm-1 to 4000 cm-1. Comparing these spectra with that of BeO powder, a view about the assignment for BeO infrared spectra is given.
Studies on Thin Polycrystalline Layers of Thallium Selenide
Authors: Mangalam Mary Juliana , Rao K. Nagaraja , Ranganajan N. , Siddiqi M. I. A. , Suryanarayana C. V.
Published: November 2005

Photosensitive thallium selenide cells have been prepared by previous workers by vacuum evaporation. We have succeeded in depositing these layers chemically for the first time. The characteristics of these deposited layers such as spectral response, effect of dopants and structure are studied and discussed.
Thermal Instability of Nonhomogeneous Fluids
Authors: Banerjee Mihir B.
Published: November 2005

The present paper is an attempt to investigate theoretically the stability of a continuously stratified layer of an inviscid fluid, statically confined between two horizontal boundaries and heated or cooled uniformly underside. The basic stratification is assumed to be of the exponential type (ρ=ρ0ēδ1
z
, δ1=constant) depending only on the vertical coordinate (z) while the fluid extends indefinitely in the horizontal directions. The stability problem is shown to depend on a single nondimensional number N(z) and it is established that the configuration is stable or unstable according as N(z) is negative or positive everywhere in the flow domain respectively. The character of the basic stratification in the presence of a uniform temperature gradient is also discussed. Some other results include a circle theorem concerning the growth rate of an arbitrary oscillatory mode and the characterization of the neutral modes and the marginal state.
Bottom Pressure of Powder Bed with Applied External Pressure
Authors: Senna Mamoru , Kuno Hiroshi
Published: November 2005

External pressure was applied onto the surface of the powder bed in a cylindrical container. Linear relations between external and bottom pressures as expected from Shaxby's equation were observed in the increasing external pressure process. From this linear relation, a powder parameter c was obtained.
When a sufficiently large and rough-walled cylinder was used, c is regarded as a parameter expressing the combined property of friction and cohesion of the powder bed, and had a linear relation with the rate of tapping compaction which suffered little wall effect.
Au-Cu Alloy and Ag-Cu Alloy-Silicon Schottky Barriers
Authors: Arizumi Tetsuya , Hirose Masataka , Altaf Naseem
Published: November 2005

Schottky barriers formed by vacuum depositions of Au-Cu and Ag-Cu alloys on n-Si (111) surfaces were investigated. The barrier height of the two systems changes in a linear fashion with the composition of the alloy as found in Au-Ag alloy-Si contacts. The linear variation of the barrier height with composition is attributed to a corresponding composition dependence in the work function of the alloy.
Aging Effect of Electrodeposited Ni-Fe Thin Films
Authors: Arai Yasuyo
Published: November 2005

A deterioration phenomenon was observed in the rate of flux reversal of electro-deposited Ni-Fe thin films from a sulfate bath, as time elapsed after electrodeposition. No noticeable deterioration was found in the flux reversal of a specimen which was deposited at higher current densities than 100 mA/cm2. Under the plating conditions at lower current densities than 100 mA/cm2, weak acidity and concentrated ferrous ion in a solution promoted the deterioration. Furthermore, high bath temperatures gave increased deterioration, whereas an addition of a wetting agent into the solution improved such a deterioration phenomenon to some extent.
Viscosity Measurement of Synthetic Fused Quartz by Beam-Bending Method
Authors: Kimura Tomisi
Published: November 2005

According to the process of preparation fused quartz is classified into three types: electric-melting, flame-fusing and synthetic fused quartz, Viscosity is determined by the beam-bending and the fiber-elongation method, the former being the measurement of the sagging rate of a linear specimen. For synthetic fused quartz which contains more hydroxyl than the other types, viscosity is varied with time at high temperatures even if the specimens have been annealed completely. This viscosity change is investigated from the point of view of hydroxyl decrease by infra-red absorption and electron diffraction. It is evident that excess hydroxyl in synthetic fused quartz decreases with increasing time at high temperatures and α-cristobalite is crystallized on its surface. It is suggested that a more exact value of viscosity will be obtained from the beam-bending than the fiber-elongation method for the excess-hydroxyl-containing fused quartz such as synthetic one.
Structure Changes in Fe-23 at.% Be Alloy
Authors: Yagisawa Kohei , Yoshida Hidehiko
Published: November 2005

Structure changes in Fe-23 at.% Be alloy aged at temperatures between 300° and 800°C were studied by transmission electron microscopy. The structural changes with aging were classified depending on aging temperatures as follows: 1) 300° to 400°C; ordered structure, modulated structure, continuous precipitation of 1st metastable phase and discontinuous precipitation of 2nd metastable phase without grain boundary migration. 2) 500° to 800°C; continuous precipitation of 1st metastable phase in matrix, formation of discontinuously precipitated regions along boundaries, and continuous precipitation of stable phase in matrix. 3) Above 800°C; formation of dislocation networks, stable phase precipitation on them, and further formation of finer dislocation networks and precipitates. The structure of 1st metastable phase was f.c.c. and expected to be Laves phase of MgCu2 type. Variously shaped stable phase precipitates were Laves phase of MgZn2 type.
Generation of Sound Pulses with Finite Amplitude in Free Air
Authors: Nakamura Akira , Takeuchi Ryoichi
Published: November 2005

Finite amplitude sound pulses are radiated into the free air space by using transducer of electro-magnetic induction type. For the purpose of finding the relationship between the acceleration of the source plate and the sound pressure of the radiated pulses, some measurements are made. In the range of the low acceleration of the source plate, the experimental values for the peak pressure of the radiated sound pulses agree fairly well with the theoretical values for the radiation of the infinitesimal sound waves from circular piston. However, in the range of the high acceleration, these two are not in agreement. Taking account of the attenuation by the absorption of sound in the medium, the peak pressure and the width of the sound pulses propagating through free space are measured. It is found that the attenuation coefficient in free space is proportional to the peak pressure at a reference distance in the free field, if the pulse width is constant.
Magnetic Properties of Ferromagnetic Metal Alloy Fine Particles Prepared by Evaporation in Inert Gases
Authors: Kusaka Katusi , Wada Nobuhiko , Tasaki Akira
Published: November 2005

Single domain fine particles about 150 Å in diameter, of alloys of Fe, Co and Ni were prepared by evaporation in an atmosphere of argon at 3 Torr. The particles were coupled with each other like a necklace. The X-ray diffraction analysis revealed that the lattice parameters of the alloy particles agreed with those of the original bulk alloys within an experimental error of 0.3%. It was indicated, however, that they might be smaller than the latter within that error. The maximum coercive force observed in Fe–Co alloys was about 1.5 kOe. It was found that the oxidation of Fe–Co alloys can be prevented by adding some Ni. The magnetic orientation of particles caused by application of a magnetic field during the evaporation was studied. In a magnetic field of 0.5 kOe the necklace structure was aligned parallel to the field and a magnetic anisotropy of 3.5×105 erg/g appeared in this oriented sample. This strong anisotropy is considered to be due to a shape anisotropy induced by alignment.
An Automatic Temperature Controller for Cryogenic Systems
Authors: Arajs S. , Conroy J. W.
Published: November 2005

An autormatic temperature controller, providing constant temperatures to within ±0.01°K between 4 and 400°K, is described. This unit is useful for studies of electric, magnetic and thermal properties of different solid materials.
Evidence of Screw Dislocations in KCl Single Crystals
Authors: Patel A. R , Chaudhari R. M
Published: November 2005

(100) cleavage faces of KCl single crystals have been etched in a solution of 90% absolute ethyl alcohol, 5% n-butanol, 3% distilled water and 2% formaldehyde, and spiral etch pits both clockwise and anticlockwise are produced. By etching matched pairs of faces in the same conditions one to one correlation in the number, position, shape, and sense of the spirals are obtained. By re-etching a cleavage face on which spiral depressions were produced, in another etchant, square shaped pits exactly at the centres of each spiral depression are produced, indicating thereby that the centres of the spiral depressions are the sites of screw dislocations. It is observed that when a cleavage face is successively etched for two different periods, the spiral depressions produced during the first etch grow in size while their shape and sense remains the same. The implications are discussed.
Current Oscillations and High-Field Domains in Photoexcited High-Resistivity GaAs
Authors: Tokumaru Yozo
Published: November 2005

Current oscillations (10 kHz∼102kHz) due to the periodic generation of a moving high-field domain have been observed in high-resistivity GaAs (∼3×103ohm-cm in the dark) under illumination at room temperature. It has been found that threshold field for the oscillation decreases with increasing illumination level and lies in the range from 650 V/cm to 2100 V/cm. Properties of the high-field domain have been investigated by a light probe and a contact probe technique. The domain velocity is 103cm/sec∼104cm/sec. Width and field of the domain are of the order of 10-2cm and 104V/cm, respectively. By shifting a light spot position along the specimen to change the distance that the domain transits, the oscillation frequency can be varied continuously. The origin of the oscillations can be explained with field-enhanced electron trapping at deep levels.
Quartz Crystal Microbalance Techniques Applicable to the Studies of Sulphuration and Oxidation of Thin Metal Films
Authors: Shiojiri Makoto , Hasegawa Yasuo , Murata Yukio , Matsumura Shoichi
Published: November 2005

A quartz crystal microbalance which detects a mass change of 0.35×10-2µg/cm2and has a drift less than 1 Hz over a day has been constructed for measurement of weight gain due to chemical reactions. The frequencies of two oscillators, standard and specimen oscillators, are mixed and the difference frequency is measured by a counting-rate meter. To reduce the difference frequency at any stage the frequency of the standard oscillator is continuously changed by replacing the quartz crystals and by controlling a variable condenser connected with the crystals. A compensation method is employed for reducing the effects of the temperature fluctuation at higher temperature and of the pressure change of the surrounding gas. The ripples of frequency at 200°C can be reduced to less than 3 Hz. Some examples of the weight gain data for sulphuration and oxidation of vacuum-deposited metal films are presented.
Theory of Pinning Effect on the Nonlinear Resistance in the Mixed State of Type II Superconductors
Authors: Sugahara Masanori , Ohta Tokio
Published: November 2005

A mechanism is proposed for the nonlinear flux flow resistance in the mixed state of type II superconductors. Beside of the frictional drag which is responsible to the linear resistance, the flux line motion is subjected to the pinning effects, which are appreciable especially when the Lorentz-like driving force is small, that is to say, in the small current region.
The flux line is pinned down for a time τ
r
, which decreases with the increase of the Lorentz-like force, at each pinning center and for the rest time τ
r
, no voltage appears while the currents flow. The dislocation-immigration analogue in the imperfect lattice is used for the line motion to calculate τ
r
and the result shows the nonlinear resistance in good agreement with the experimental results.
Computer Simulation of Silicon Read and p-n-n+ IMPATT Diodes under Large Signal Conditions
Authors: Matsumura Masakiyo
Published: November 2005

Computer simulations of silicon Read and p-n-n
+ diodes under large signal conditions reveal that the p-n-n
+ diode oscillates with a pulsed electron current as the Read diode and the field gradient in an active region of the both diodes is an important factor for high output power.
Magneto-Hydrodynamic Pivoted Slider Bearing with a Convex Pad Surface
Authors: Kapur V. K.
Published: November 2005

A theoretical analysis is presented for a pivoted slider bearing in the presence of azimuthal magnetic field. The analysis takes into account the pad curvature which is usually neglected. The effects of pad curvature and magnetic field are simultaneously shown in a family of curves and some interesting results are obtained.
Ionisation in Detonationswellen
Authors: Terao Kunio , Neda Toshikatsu , Nakao Katsunori , Sato Tadashi
Published: November 2005

From the results obtained by the double probe method with a high frequency multistep pulse voltage, some aspects of the ionization of detonation waves in propane-oxygen mixtures and the influences of shock waves there on were explained. The experimental results further show that it is possible to obtain a relatively stable high speed plasma flow having about 1012/cm3 ion density through a Laval nozzle from reflected detonation waves. They suggest also that the plasma of detonation should be isothermal.
Current Oscillation and Some Photoelectric Properties in High Resistivity Gallium Arsenide Produced by Irradiation of Fast Neutrons
Authors: Shirafuji Junji
Published: November 2005

Current oscillation and some photoelectric properties in high resistivityn-type GaAs produced by fast neutron irradiation have been investigated. The spectral response in the photocurrent has a broad peak near the band edge and a relatively high photo-sensitivity still remains at wavelengths longer than the band edge. The photocurrent shows a drastic thermal quenching which begins at about 350°K. In as-irradiated and annealed samples current oscillations caused by traveling high field domain are observed. It is concluded that the current oscillation is due to the field-dependent trapping effect. The current oscillation at room temperature launches even in the dark, while at low temperatures it occurs only under illumination of light. The lower limit ofn·lproduct necessary for leading to the oscillation is estimated as 5×108cm-2. The oscillation characteristics, especially at low temperatures, are well understood by a simple model.
Evaluation of the Amplitude-Dependent Internal Friction of Materials under Inhomogeneous Strain
Authors: Asano Shigeru
Published: November 2005

The phenomenology of the internal friction experiments is examined with special attention to the influence of the distribution of vibrational strain. A method is presented for the determination of the strain dependence of internal friction from the data obtained under inhomogeneous strain. It is shown that measured values of internal friction, expressed usually as a function of the maximum strain amplitudesεm, are dependent on the strain distribution and that the strain-amplitude dependence of internal friction can be obtained by plotting the measured values against the average strain amplitudeεa, given byεa=Kεm. The factorKcan be calculated from the mode of vibration. The result for a cylindrical specimen of common materials shows thatK=0.8165 for torsion, 0.8660 for a free longitudinal mode and 0.6059 for a free transverse mode.
Fraunhofer Diffraction Pattern Deflected by Highly Absorbed Ultrasound
Authors: Uchida Naoya
Published: November 2005

Intensity distribution has been calculated in the Fraunhofer diffraction pattern of the deflected light. The aspect of the variation in the pattern has been obtained for various values of a parameter; a product of the ultrasonic absorption coefficient and one half of the incident beam aperture. The limit of resolution of adjacent spots has been also calculated in accordance with a few definitions concerning the minimum resolvable distance. The calculations have been ascertained by the intensity measurements of the deflected pattern for several kinds of liquids with various absorption coefficients.
The Developing Time Dependence of the Factor (R) in Hull's Equation to Calibrate Quantitatively the Mass Spectrometric Spectrum
Authors: Grais Khairi I.
Published: November 2005

A second order mass spectrometer with an ion source (electron impact one) and ILFORD Q
1 emulsion as an ion detector has been used to investigate the developing time dependence of the factor (R) in Hull's equation as a method of mass spectrometric quantitative analysis of atomic ions. Hull's equation in its modulated form shows good agreement with the experimental data.
Epitaxial Vapor Growth of Gallium Antimonide
Authors: Kakehi Masahiro , Shimokawa Ryuichi , Arizumi Tetsuya
Published: November 2005

Epitaxial vapor growth of gallium antimonide in the closed tube process is studied using polycrystal gallium antimonide and hydrogen chloride as the source crystal and the transport agent respectively. The transport rate is maximum when the hydrogen chloride concentration initially charged in the reactor is about 10-7 mole per unit volume.
The surface morphology of the grown layer is strongly dependent on the pretreatment of substrate surface: The grown layer is mirror-smooth when the substrate surface is vapor-etched in situ for about 30 minutes preceding to the deposition.
The electrical properties of the grown layers are studied by using the Pauw's method. The hole concentration in the grown layer obtained in the routine experiment is comparable to or smaller than the lowest value ever reported (3∼4×1016 holes/cm3), and the hole mobility ranges from 700 to 800 cm2/V·sec without any indication of compensation.
Photoconductivity of CdSe Films Prepared by a Vapor Evaporating-Reactive Sputtering Method
Authors: Tanaka Kuniaki
Published: November 2005

CdSe films are prepared by a vapor evaporating-reactive sputtering method. A cadmium cathode is sputtered in the Se vapor carried by argon or hydrogen gas to the glow discharge region. The photoconductive sensitivity of the deposited film increases by annealing in argon gas. The ratio of the light current to the dark currentIl/Idis as high as 107. The surface adsorption effect of oxygen on the large photoconductivity of the sputtered film is discussed by the Elovich theory. The dark resistance of the sensitized CdSe film is determined by the surface oxygen which is chemisorbed as a acceptor type adsorbate, and the photosensitivityIl/Idis strongly dependent on the surface chemisorbed oxygen. The overshoot of the light current is due to the photo-adsorption process, which is also discussed by the solution of Elovich equation.
A New Instability in MOS Transistor Caused by Hot Electron and Hole Injection from Drain Avalanche Plasma into Gate Oxide
Authors: Hara Hisashi , Okamoto Yoshihiko , Ohnuma Hiroie
Published: November 2005

Results of an experimental study are reported of a new instability found in p- and n-channel MOS transistors. This phenomenon is that when a higher voltage in an excess of a brakdown voltage is applied to the drain electrode the breakdown voltage drifts to a higher value and the drain current also increases. The origin of this instability is investigated by extensive measurements and analyses of the electrical characteristics of the transistors. It is concluded that 1) the semiconductor surface near the drain becomes p-like in the p-channel transistors and n-like in the n-channel transistors and thus the active channel length is shortened, 2) this is caused by charging of the gate oxide due to injection of electrons or holes generated during the drain avalanche breakdown, and 3) electron and hole injection is much affected by electric field across the oxide over the drain junction.
Nonlinear Infrared Transmission in Gaseous SF6 Induced by Q-Switched CO2 Laser Radiation at 10.6 µm
Authors: Ohtsuka Yoshihiro , Yoshimura Takeaki
Published: November 2005

The transparent effect in gaseous SF6 has been experimentally studied by means of CO2 laser radiation at 10.6 µm. A beam of CW laser radiation of about 100 mW is transmitted through an absorption cell of 1200 mm long with SF6. An increase in the transmitted power of CW laser radiation can be directly observed on an oscilloscope when SF6 is excited by a pulse of Q-switched laser radiation of about 1 KW cm-2. The transmitted radiation power begins to increase with some time-delay as compared with the Q-switched pulse for excitation. This time-delay at the peak transmission becomes minimum at the pressure of SF6 which gives rise to the maximum transmittance. The typical transmittance varies from 5 to 80%. The transmitted radiation power recovers to its original value with a decay time of 0.2 to 0.3 µs at lower pressures of SF6 after it reaches the maximum.
Energy-Mass Analysis for Highly Ionized Steady State Plasma
Authors: Ishimaru Hajime
Published: November 2005

This paper describes the design and the construction of the electrostatic analyzer for low energy of about 10 eV charged particles, and time-of-flight mass spectrometer with mass resolving power of less than 30 for 50 eV ions. With application of gated counting method, accurate energy distributions for each ion species have been obtained. Ion temperature and density ratio of each ion species for highly ionized steady state plasma have been also determined.
Space Charge Effect in Lead Zirconate Titanate Ceramics Caused by the Addition of Impurities
Authors: Takahashi Masao
Published: November 2005

Lead zirconate titanate ceramics containing metal oxides as impurities are subjected to poling, in order to give rise to piezoelectric activity, at various temperatures. Impurities contained in the ceramics are found to be divided into three groups according to their effects on poling temperatures. (1) When the amounts are small, piezo-electric activity is lowered by poling at low temperatures, but not so when the amounts increase. (2) Irrespective of the amounts the activity is lowered by poling at low temperatures. (3) Irrespective of the amounts the activity is independent of poling temperatures.
Lowering of piezoelectric activity is accompanied by an increase of specific resistivity. The lowering is explained by the effect of space charge which is generated by the addition of impurities. An empirical formula on poling efficiency is derived in terms of space charge and specific resistivity of the ceramics.
Etude par Diffraction Electronique de la Structure des Carbures de Tantale
Authors: Terao Nobuzo
Published: November 2005

Thin films of tantalum carbides were prepared by heating the doubly evaporated film of (tantalum+carbon) in vacuum at high temperature and the existence of two phases was identified by electron diffraction analysis: TaC and Ta2C. The TaC phase has the NaCl cubic structure and its lattice parameter varies largely according to the composition. In the most carbon-deficient crystal, the lattice parameter is a=4.42 Å and it increases to a=4.458 Å corresponding to the stoichiometric TaC. The Ta2C phase has the C 6 structure (P3̄m1-D
3
3d
), similar to the CdI2 antitype structure. The lattice parameters are a=3.104 Å and c=4.938 Å (c/a=1.591).
Photocurrent Oscillations in Oxygen-Doped Gallium Arsenide
Authors: Bhattacharya Tapan K.
Published: November 2005

Photocurrent oscillations in boat-grown oxygen-doped-GaAs (dark resistivity from 3.0 to 106ohm cm) are studied at different temperatures under white-light illumination and at 80°K under monochromatic excitation. Higher-resistivity samples show oscillations 20–50°K below room temperature and the oscillation characteristics (period and amplitude) follow closely the variation in the steady-state photocurrent with temperature. Lower-resistivity samples oscillate only at temperatures \lesssim100°K. The oscillation characteristics of all the samples of different dark resistivity follow the spectral response curves at 80°K. From the experimental observations, an energy diagram is presented to explain the phenomenon of photocurrent oscillations in these crystals. It is concluded that two acceptor levels, respectively 0.22 eV and 1.3 eV below the conduction band, are responsible for this phenomenon. The 1.3 eV level is found to be responsible both for the photoconduction and field-dependent trapping of the photoexcited electrons.
Spectral Distribution of the Light Scattered from Dilute Solutions of Optically Anisotropic Flexible Macromolecules (Forward Scattering)
Authors: Ono Kazuhiko , Okano Kōji
Published: November 2005

The spectral distribution of the light scattered in the forward direction from the dilute solution of optically anisotropic flexible macromolecules has been calculated based on the spring and bead model (the Rouse model) with the Kirkwood-Riseman approximation. The calculated spectrum is the superposition of various Lorentzian curves, each of which corresponds to the internal mode of the intrachain movement of flexible macromolecules. It is also found that each mode contributes to the scattered intensity with equal weight.
An Electric Model for Flat Simple Epithelial Cells with Low Resistive Junctional Membranes. A Mathematical Supplement
Authors: Shiba Haruo
Published: November 2005

A theoretical model, Heaviside's `Bessel cable', for flat simple epithelial cells with low resistive junctional membranes was already discussed in another paper in relation to the electric properties of the amphibian gut epithelium. This paper is intended to supplement the mathematical side of the theory. The differential equations for potential and current distribution associated with the radial spread of a current injected into a thin membrane-bounded layer of cytoplasm are formulated. The steady-state and more general solutions are derived with application of the Laplace transformation technique. An asymptotic expansion of the transient solution is also presented, which might be useful for estimation of the cell membrane capacitance.
Chemisorption and Absorption of Nitrogen with Tantalum
Authors: Oguri Takeo
Published: November 2005

Sorption of nitrogen on polycrystal tantalum ribbons is studied using a static method in ultra-high vacuum. Saturation coverage is 3.6×1014 molecules/cm2. Sticking probability at room temperature is 0.17 UP to 1.4×1014 molecules/cm2, and abruptly falls to 0.03 at about 2×1014 molecules/cm2. This suggests the existence of multiplex adsorption states in this system. The absorption occurs at temperatures above 500°K, so the desorption from the chemisorption states is not observed. From an analysis of the absorption rate, the nitrogen atoms chemisorbed on the surface of the polycrystal ribbon is shown to be absorbed at the grain boundary. The activation energy of absorption is 1.8 eV/2-atoms, and is much smaller than that of diffusion of nitrogen in tantalum. As the concentration of nitrogen in tantalum is proportional to the square root of equilibrium pressure, nitrogen is absorbed in atomic form into the bulk. Desorption from the absorption state is observed at temperatures above 1800°K. The heat of absorption is 4.4 eV in the pressure range from 10-8 to 10-2 Torr.
ESR Study on Surface Properties of Semiconductor. II. III–V Compounds (GaAs, GaSb and InSb)
Authors: Mizutani Teruyoshi , Shimakawa Koichi , Arizumi Tetsuya
Published: November 2005

Crushed samples of III–V compounds (GaAs, GaSb and InSb) show a narrow ESR signal withg=2.0027±0.0003 after vacuum heat-treatment in vacuum. It is concluded that dipolar interaction between the ESR centers and the adsorbed O2molecules broaden the line width and reduce the signal height. By assuming that the line broadening is proportional to the coverage of O2molecules on the semiconductor surfaces, heat of adsorptionQis obtained for the physically adsorbed oxygen on the surface of III–V compounds;Q=1.9±0.3, 1.8±0.3 and 1.8±0.3 Kcal/mole for GaAs, GaSb and InSb respectively. The changes of the line width with air pressure suggest that some of O2molecules on the surface condense to form O4molecules at -150°C.