bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Structure of Evaporated Gold Particles by Means of a High Resolution Electron Microscope
Authors: Komoda Tsutomu
Published: November 2005

The structure of evaporated gold particles were examined through the (111) lattice image observation. The results obtained confirmed Ino's analysis (1966) that the particles are of multiple-twin structure and have external shapes of either decahedron or icosahedron. It was also found that the structures are already completed at the initial stage of deposition when the particle size in smaller than 20Å, but the particles no longer keep their initial structures when they grow beyond about 150Å in size. Neither gaps nor dislocations were observed in the particle image; instead, lattice images were found to be composed of lines not exactly parallel to each other, but slightly diverging outwards. These observed facts suggest that the particle nucleus consisting of several atoms forms the smallest unit of either decahedron or icosahedron and growth proceeds layer by layer of atoms on the nucleus.
Fast Discriminator with Zero-Crossover
Authors: Ryu Norio
Published: November 2005

A fast discriminator has been designed to discriminate the pulses from a photomultiplier anode. To match the capabilities of recent electronic circuits dealing with fast pulses in nuclear experiments, a precise time information is extracted from the discriminator using the triggering function of an Esaki-diode. This is done by determining the zero-crossing pint of pulses formed by adding reflected pulses returning from a coaxial cable connected to the input pulses. The performance of the fast discriminator has been examined by use of simulated pulses similar to those from a photomultiplier anode. The time jitter of output pulses is less than 1 ns over the range of input pulse heights between 8 mA and its discriminating point of 0.8 mA. Five outputs are provided of 4 mA in pulse height and about 6 ns in width. Although the output pulses do not have a rectangular form, the rise times at the beginning and the end of the pulses up to 2 mA are about one nanosecond. An attenuator for fast pulses, matching 75 Ω coaxial cables, is also reported.
Josephson Current Limited by Self Field
Authors: Yamashita Tsutomu , Kunita Masanori , Onodera Yutaka
Published: November 2005

The maximum Josephson current I

Jmax is affected by the self field in ordinary junctions. The self field limiting I

Jmax is discussed in this report. It makes clear quantitatively how much smaller the maximum I

J
is than the calculation by Ambegaokar and Baratoff.
Growth of Strontium Titanate Single Crystals from Molten Salts
Authors: Sugai Tokukō , Hasegawa Shuzo , Ohara Gisaku
Published: November 2005

Single crystals of strontium titanate (SrTiO3) were grown by flux method. The best results were obtained with KF-LiF and KF-K2MoO4 flux systems. Reasonably large single crystals were yielded from the solvent of KF-LiF systems and fine small crystals which were colorless, transparent and flawless were obtained from KF-K2MoO4 systems.
The experiments were carried out by slow cooling method, temperature of growth being 1250°C and cooling rate 2–5°C/hr. The single crystals obtained were 4 mm in size on an average and larger ones 7 mm across. The crystal habits were all cubic in form.
Evaporation Spirals and Loops on KCl Single Crystals
Authors: Patel A. R. , Chaudhari R. M.
Published: November 2005

Cleavage faces of potassium chloride single crystals have been thermally etched. The thermal etch patterns consist of irregular spiral patterns and closed loops. Inter-ferometric study has revealed that they are depressions. The centres of the spirals are not distinct. It is therefore conjectured that the spirals without distinct centres might have been formed as explained by Lang (1957). While the patterns similar to that developing at Frank-Read sources and the complicated pattern originating from number of sources concentrated in a small region may be due to screw dislocations.
Electroluminescence of ZnS: Mn, Cu, Cl Films
Authors: Uchida Wakio
Published: November 2005

In sandwich and gap cells of ZnS: Mn, Cu, Cl films, the emitting portion of electroluminescence under ac and dc excitation was investigated by microscopic observation. The relation between the brightness and the polarity of applied voltage was also examined. In the case of ac excitation, overlap of emitting layer was observed in sandwich cell, while in gap cell the emission originated from various portions such as along the both electrodes, along some deposit or at spots distributed throughout the gap. In the case of dc excitation in the sandwich cell, the emission was stronger and more homogeneous under the positive metal electrode than under the negative one. The emission in gap cell under dc excitation always originated from the anode. Current-voltage characteristics of films have no direct connections with brightness. From these results, it seems that dc electroluminescence of ZnS: Mn, Cu, Cl films is excited by the hole injection from the Cu-rich phase to the ZnS phase.
Microwave Conductivity and Relaxation of Excess Phonons in CdS
Authors: Arizumi Tetsuya , Umeno Masayoshi , Fukui Masuo
Published: November 2005

The transmitted microwave power (9Gc/s) through a CdS sample increases with increasing applied electric field. This increase is interpreted in terms of the sample resistance due to the enhancement of the scattering of electrons by built-up excess phonons. Using the same microwave techniques the decay time of built-up excess phonons was measured. The decay time was about 0.37 µsec in good agreement with the estimation from Holland's experimental formula. The decay process was discussed following the theory of Yamashita and Nakamura and it was concluded that the decay time, experimentally obtained, means the phonon-phonon relaxation time.
Non-Destructive Measurement of Surface Concentrations and Junction Depths of Diffused Semiconductor Layers
Authors: Abe Toshio , Nishi Yoshio
Published: November 2005

Infrared reflectivity of the diffused semiconductor with continuously varying impurity concentration is treated strictly, and computed numerically using an electronic computor. It is shown for thin diffused layers in silicon used for the ordinary planar technology that the wavelength of a reflectivity minimum, λmin, depends not only on the surface concentration, but also the diffusion depth. It has been found that the surface concentrations and junction depths of the diffused semiconductor layer can be determined non-destructively using λminand sheet resistivity, provided the following seven conditions are satisfied. (1) Semiconductor materials (2) type of conductivity (3) bulk concentration (4) function-type of diffused impurity profile,F(x), are given, (5)pnjunction is formed by diffusion, (6)F(x) has not unknown parameters except for the diffusion length of diffused impurity, √Dt, and (7)F(x) is a monotonic decreasing function. The figures usable for the above purpose are given forn-type complementary error function layer andn-type Gaussian layer in Si.
Measurement of the Optical Constants of Yttrium Oxide
Authors: Nigara Yutaka
Published: November 2005

By using a solar furnace, yttrium oxide crystals were grown by the fusion process. The crystals obtained were highly transparent in the spectral region from 0.25 to 9.6 µ. The refractive index in this region was measured by three different methods. The observed index values were well expressed by the dispersion formula. From the values of parameters in the formula, it was found that the center of the fundamental absorption and the lattice absorption were at about 0.139 and 22.9 µ, respectively. A brief discussion on the infrared and ultraviolet absorption edges is added.
Analysis of Population Inversion for Lasing Threshold in Semiconductors
Authors: Sato Hisanao
Published: November 2005

The rate of recombination due to spontaneous emission of light at lasing threshold is calculated for a direct band gap semiconductor. The recombination rate for doped semiconductor, where the donor state is assumed to be discrete, is numerically estimated in the temperature range from 50°K to 400°K and compared with the undoped case. It is shown that the threshold of excitation rate for lasing action is decreased by introducing donors (or acceptors) to a host semiconductor.
An Application of Information Theory to Pulsed Nuclear Radiation Measurement
Authors: Narita Masakuni , Ozawa Yasutomo
Published: November 2005

A new method for pulsed radiation measurements is studied by an application of the information theory of discrete systems. It is derived from entropy concept that in order to measure the photon density with the maximum conversion rate of a counter subjected to pulsed photon beams, the density λ of a Poisson source must satisfy the relation of λb=ln
2 when the resolving time τ of the counter lies between the pulse width b and the period (1/f).
Actual devices using feedback circuits for satisfying the above condition are proposed.
X-Ray Micrographic Observation of Imperfections in Si Wafer near the Oxide Film Edge before and after the Localized Diffusion
Authors: Nimura Hiroshi , Ito Nobuo , Nakau Tanehiro , Nakahara Osamu
Published: November 2005

Imperfections in the region near the edge of oxide film on a silicon wafer was observed by the use of a Lang camera. Before diffusion, an elastic strain field caused by the oxide film edge was observed in the region near the edge. As the impurity concentration of localized diffusion became high, the state in this region changed, showing that the diffusion process caused a strain, and generated dislocation arrays. It was found that inhomogeneity of distribution of diffusion-induced strain at the edge and inside the diffused region near the edge is very likely responsible for the formation of these dislocation arrays.
Normal Stress Effect in Dilute Solutions of Poly-n-butyl Methacrylate in Chlorinated Diphenyl
Authors: Tamura Mikio , Kurata Michio , Osaki Kunihiro , Kajiwara Kanji
Published: November 2005

Normal stresses and the shear stress in steady shear flow as well as the dynamic complex modulus are measured for dilute solutions of poly-n-butyl methacrylate in chlorinated diphenyl, in the range of concentration, 0.2∼1.0 wt.% and of molecular weight, 5.21×105∼2.30×106. The secondary normal stress was negligibly small compared to the principal one when the rate of shear was low. The steady shear compliance was proportional to the number of polymer molecules in the solution and its magnitude was of the order predicted from the spring-beads model theories. A relatively strong tendency to non-Newtonian effect was observed for the solutions with relatively high concentrations, and the reduced plot which was successfully performed for polystyrene solutions failed in this case at high rate of shear.
Sheet Resistivity of the Epitaxially Grown Germanium Layer
Authors: Arizumi Tetsuya , Nishinaga Tatau , Kakehi Masahiro
Published: November 2005

The vapor deposited layer of germanium usually contains a considerable number of lattice imperfections lowering its resistivity. The distribution of the defect concentrations is not uniform over the grown layer; it is maximum at the interface between the substrate and the grown layer and it decreases as leaving the interface, to disappear almost perfectly at a distance 10∼20 µ from the interface. Such a non-uniform distribution is essentially the same, whether the layer will be produced through the open tube or the closed tube process, and whether they will be vapor-etched in situ or not. The results suggest that the mechanism producing the imperfection centers is determined by the surface condition of the substrate or the existence of non-equilibrium adsorption state.
Investigation of Microprecipitates in Highly Te-Doped GaAs Crystals
Authors: Iizuka Takashi
Published: November 2005

Inhomogeneities in highly Te-doped, melt-grown GaAs crystals carrier concentrations more than 1.6×1018 cm-3 have been investigated using etching technique, X-ray anomalous transmission, and electron microprobe analysis. Microstrains, arising from impurity precipitates produced either fine etch pits on the etched surface or contrast of small specks on the X-ray topographs. A microprecipitates-free was observed around a dislocation, and qualitatively analyzed. Small angle boundaries were observed, and the impurity concentration difference across the boundary was detected.
Electronic Absorption Spectrum of K2NiF4
Authors: Tiwari J. S. , Mehra A. , Srivastava K. G.
Published: November 2005

The optical absorption of K2NiF4 single crystal has been studied and the characteristic spectrum of Ni2+ in octahedral field of F- ligands is observed. The bands are assigned to various excited levels of Ni2+ in O
h
symmetry and values of the crystal field parameters B, C and Dq are found to be 965, 4135 and 755 cm-1 respectively.
A Study of Gettering Effect of Metallic Impurities in Silicon
Authors: Nakamura Masakatsu , Kato Taketoshi , Oi Noboru
Published: November 2005

Gettering effect of metallic impurities such as Cu, Fe and Au was studied by using the radioactive tracers. It was ascertained that the glass was not the only agent responsible for the glass gettering but outdiffusion and precipitation of impurities at lattice defects near the surface region had also an important effect on glass gettering. Mechanism of glass gettering varies drastically according to the kinds of impurities. That is, Cu is not found in the glasses and it is mostly gettered by outdiffusion regardless of the existence of the glasses. About a half of Fe is gettered in the glasses and the remainder is gettered by outdiffusion or precipitations at dislocations under the glasses. As to Au, gettering effect considerably depends on the atmosphere in which the slices are diffused. Boron nitride converted from boron glass during heat treatment in nitrogen atmosphere seems to be most effective in gettering Au from silicon.
On the Triangle Path Interferometer
Authors: Yoshihara Kunio
Published: November 2005

An explicit formula giving the optical path difference of the triangle path interferometer is obtained by applying the same principle as used in the operator formulation in optical instrument design. The result shows that the interferometer gives fringes of equal inclination in usual cases and hence extended light source can be utilized so that greater luminosity is available than in the case of fringes of equal thickness. Several properties of this interferometer are also discussed.
On the Electrical and Thermal Properties of the Ternary Chalcogenides A2
IBIVX3, AIBVX2 and A3
IBVX4 (AI=Cu; BIV=Ge, Sn; BV=Sb; X=S, Se, Te). I. Thermoelectric Properties at Room Temperature
Authors: Hirono Katsumi , Kono Masaru , Irie Taizo
Published: November 2005

Electrical conductivity, Seebeck coefficient, thermal conductivity and microhardness of ternary chalcogenides A2
IBIVX3, AIBVX2 and A3
IBVX4 (AI=Cu; BIV=Ge, Sn; BV=Sb; X=S, Se, Te) were measured and their thermoelectric figures of merit are evaluated at room temperature. All of the compounds have positive Seebeck coefficients. The lattice thermal conductivity increases linearly with the increase of the microhardness for AIBVX2 and A3
IBVX4s eries. The Keyes' relationship between lattice thermal conductivity and melting point are applicable for AIBVX2 and A3
IBVX4 series. On the other hand, the lattice thermal conductivity of A2
IBIVX3 series does not satisfy the usual relationships mentioned above. Values of zmax, the value of the thermoelectric figure of merit at the optimized carrier concentration estimated by the formulas based on the simplified assumptions are in the order of 10-5 deg-1., 10-4 deg-1. and 10-3 deg-1. for sulphides, selenides and tellurides, respectively. The value of zmax of Cu3SbTe4 is estimated to be 2.8×10-3 deg-1.
Fluid Layer Heated from Above
Authors: Banerjee Mihir B. , Agrawal S. C.
Published: November 2005

The stability of an inviscid layer of homogeneous fluid was confined between two rigid horizontal parallel plates is investigated 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:
(i) A sufficient condition of stability is obtained for the above problem and further it is shown that the rate of growth of any arbitrary periodic disturbance for an unstable mode must be less than the maximum of 1/2|d
U/d
z| in the flow region.
(ii) Taking the coefficient of thermometric conductivity of the fluid to be very small, the problem is shown to depend on a single nondimensional number R
2 and a variational method is given for its calculation at the marginal state when the principle of exchange of stability is satisfied. Moreover for a given wave number, the complex wave velocity for an arbitrary unstable mode is shown to be confined within a semicircle in the complex plane of wave velocity.
Neutron Generator with a Self-Target Using D-T Reactions
Authors: Hara Eiichi
Published: November 2005

A mixture of deuterium and tritium ions from a high yield modified Duoplasmatron type ion source was accelerated up to 200 KeV and the yield of 14 MeV neutrons on a stainless steel target with a galvanized Ni layer, on which Ti was evaporated, was measured. The Neutron yield per unit current obtained by this method was lower by a factor of about 15 than that obtained by accelerating a D+ beam on a tritium impregnated target, but because there was no limitation on the beam current, imposed by the life of targets, a neutron yield of 2×1011 n/s was obtained. Since the neutron yield at this energy range varies as fourth power of the accelerating voltage, it can be expected to obtain much more neutrons for higher accelerating voltages.
Delineation of Structural Defects in Natural Quartz by Selective Etching
Authors: Joshi M. S. , Kotru P. N.
Published: November 2005

Etch pits along a linear low angle grain boundary, etch pits on intersecting low angle boundaries (with three and four branches), pile-up of dislocation etch pits, series of oriented etch pits along and differently oriented etch pits (at 60° and 180°) on either side of twin boundaries observed on habit prism faces are illustrated and described. Continuation of a linear low angle grain boundary from a habit prism face to a fractured prism surface of the same crystal is established. Correspondence of isolated etch pits, of non-intersecting and intersecting low angle grain boundaries and also of etch pits within and outside such twin boundaries on the two match fractured prism surfaces is established. Similar correspondence is shown for etch pits on match fractured prism surface when one of them is etched in KOH and the other in NaOH. Series of etch pits along the twin boundaries are attributed to dislocations. Rows of etch pits parallel tor-medge observed on habit rhombohedral face and also on fractured prism surface are illustrated and interpreted. Alignment of etch pits perpendicular tor-medge is attributed to polygonization.
Nature of Black Spot Defects in Quenched Gold
Authors: Yoshinaka Akira , Shimomura Yoshiharu , Kiritani Michio , Yoshida Sho
Published: November 2005

The formation and annihilation of the small so called black spot defects in quenched gold are investigated in connection with those of the stacking fault tetrahedra. No discontinuity is found between the above two defects, and the black spot defects are concluded to be small stacking fault tetrahedra.
Ordered Structure and Ion Migration in Silicon Dioxide Films
Authors: Sugano Takuo , Hoh Koitiro , Kudo Kiyoshi , Hishinuma Noboru
Published: November 2005

Structure of silicon dioxide films thermally grown on silicon was studied with electron diffraction and the effect of impurities intentionally added during oxidation was examined. The local polycrystallization of SiO2 films is enhanced by protons or boron atoms. Phosphor, on the contrary, suppresses the crystallization and antimony behaves in a similar way. Gallium has no influence on the phenomenon. Diffusion coefficient of sodium ions in these samples was also measured and activation energy for diffusion was obtained 1.0 to 1.4 eV which coincides well with those reported by other workers. These values are not affected by the presence of impurities or structural anomalies, but the diffusion coefficient itself is large where the crystallization is marked. Phosphor immoblized sodium ions and the diffusion of protons was observed instead. These effects of impurities can be explained considering their valency and sites they occupy in SiO2 network.
A Study of Resistance and Magnetoresistance in Nickel-Iron Thin Films
Authors: Mitchell Frederick C. Williams Jr. and E. N.
Published: November 2005

Experiments are reported in which (1) the resistivity has been measured as a function of thickness in 82–18 nickel-iron thin films; (2) the ferromagnetic resistance anisotropy and the fractional anisotropy in magnetoresistance have been measured as a function of thickness; (3) the fractional anisotropy in magnetoresistance is measured as a function of temperature.
The resistivity exhibits a higher value and lower mean free path than earlier measurements due to a different method of evaporation. Furthermore the functional dependence of the ferromagnetic anisotropy in resistivity and the fractional anisotropy in magnetoresistance are shown to be dependent on the method of evaporation. The fractional anisotropy in magnetoresistance is observed to fall off approximately linearly with temperature in the range from 20°C to 300°C, and to approach zero at a temperature well below the Curie point.
Irradiance Distribution in the Diffraction Patterns of an Annular Aperture with Spherical Aberration and Coma
Authors: Asakura Toshimitsu , Mishina Hiromichi
Published: November 2005

In this paper a study is made of the annular aperture with primary spherical aberration and coma using the Zernike polynomials. The three-dimensional irradiance distributions in meridional sections of diffraction images of the annular aperture with primary spherical aberration have been evaluated for a variety of cases aud illustrated in the diagram of lines of equal light irradiance. The irradiance distributions are briefly discussed. A further increase in the focal depth as compared to the annular aperture without aberration is obtained by introducing spherical aberration in it. An addition of coma in the annular aperture is also treated and the diffraction images in the central plane have been obtained for various amounts of primary coma and central obstruction. The diffraction images are shown in the diagram of lines of equal irradiance and discussed briefly.
Experimental Studies of Harmonic Generation in a Microwave Gas Discharge at 55 GHz Frequency
Authors: Tamaru Takeshi , Chiyoda Katsuji , Maejima Yoshiki
Published: November 2005

Higher harmonic radiations generated in a microwave gas discharge were experimentally investigated, using a 5.5 millimeter continuous wave of about 5 W as a power source. The effects of configuration of electrode, the gas pressure and the tip diameter of the electrode upon the higher harmonic powers were measured. The conversion efficiencies attained were 27.6 db in the second harmonic wave and 38.0 db in the third harmonic wave respectively.
Epitaxial Growth of Ge Layers on Si Substrates by Vacuum Evaporation
Authors: Ito Kentaro , Takahashi Kiyoshi
Published: November 2005

The initial growth of vacuum-deposited Ge films on Si (111) has been studied. It has been shown that single crystal Ge layers can be obtained on cleaned Si substrates in high vacuum, but that misfit dislocations exist at the interface of Ge and Si. Electrical properties of p Ge- n Si heterojunctions made by vacuum evaporation have been studied. The I-V characteristics of the diodes can be explained through the existence of misfit dislocation.
Distribution Coefficients of Various Impurities in Alkali Halides
Authors: Ikeya Motoji , Itoh Noriaki , Suita Tokuo
Published: November 2005

Distribution coefficients of several monovalent and divalent impurities were obtained for NaCl, KCl, NaBr and KBr by the method of zone melting performed in the respective halogen atmosphere. Dependence of the impurity distribution on the speed of a zone pass and on the concentration of impurity were studied in KCl doped with lead ions, whose concentration was determined by the measurements of optical absorption as well as by the usual chemical analysis. For the monovalent impurities, the distribution coefficients obtained from distribution curves agree well with those calculated from the thermodynamical expression of distribution coefficient using the theoretical energy of solid solution. The energy of solid solution of divalent impurities was calculated from the experimentally obtained distribution coefficients taking the equilibrium of Schottky defects into account and was compared with that of lattice calculation.
X-Ray Induced Photoconductivity in Anthracene
Authors: Watanabe Yasutaka , Saito Nobuyuki , Inuishi Yoshio
Published: November 2005

The photoconductivity has been studied in anthracene by irradiation with 50 kV, 0.4 µ sec X-ray pulses. The temperature dependence of hole mobility can be described in terms of a multiple-trapping mechanism; µh=3.46×102T-1.1[1+Nt/Nvexp (Δε/kT)]-1, whereNt=1.4×1017cm-3andΔε=0.19 eV, while electrons represent µe=3.6×102T-1.3, in the range from 316°K to 238°K. The schubweg per unit field is 2.6×10-5cm2/V for holes, while for electrons this value is 1.8×10-5cm2/V at room temperature. The number of collected carriers increases with temperature with the activation energies of 0.02 eV forT≥270°K and of ∼0.06 eV forT<270°K where carrier recombination is predominant. It is shown that in the broad conductivity state wherein electrons have a long mean free path of ≥100Å, the probability for escaping from the attractive coulomb field is more than 4×10-1.
Degradation of Ge-Doped and Zn-Doped GaAs Tunnel Diodes
Authors: Satoh Hidekichi , Imai Tetsuji
Published: November 2005

Degradation of the electrical characteristics during forward operation and high temperature storage has been studied in the Ge-doped and Zn-doped GaAs tunnel diodes.
Degradation rate of the peak current under forward operation has been found to be quite similar in the both kinds of diodes. When annealed at temperatures around 300°C, tunneling current of the Ge-doped diode decreased monotonically with annealing time. On the contrary, in the case of the Zn-doped diode, an anomalous increase in the tunneling current is observed during similar heat treatment.
Diffusion constant of acceptor germanium has been evaluated from the fall rate of the peak current of Ge-doped diodes during high temperature storage. The diffusion constant obtained is of the form D=D
0exp
(-Δ
E/k
T) where D
0=54 cm2/sec, and Δ
E=2.3±0.1 eV.
Ion Diffusion and Disaccommodation in Ferrites
Authors: Ogawa Seiya , Nakajima Tomoen , Sasaki Tatsuji , Takahashi Masaru
Published: November 2005

In various mixed ferrites, the relationship between disaccommodations (DA) and cation vacancy densities was investigated, the latter being estimated from the diffusion coefficients of isotopes. The relaxation time of DA–I observed at approximately 250°C was in agreement with an extrapolated value from the cation diffusion at elevated temperatures, and the two activation energies were nearly equal, 1.5 eV. The magnitude of DA–III observed at room temperature did not necessarily correspond to the vacancy density, i.e., an iron-poor Mn–Zn ferrite containing an appreciable amount of the vacancies did not exhibit DA–III.
High Temperature Gas Reaction Specimen Chamber for an Electron Microscope
Authors: Hashimoto Hatsujiro , Naiki Toshio , Eto Terukazu , Fujiwara Kishio
Published: November 2005

High temperature gas reaction specimen chamber for an electron microscope has been constructed. The specimen under electron microscopic observation can be heated at about 1000°C in a gas layer at a pressure of about 300 Torr. The specimen is placed on a film covering the minute hole in the platinum ribbon and heated by an electric current sent through the ribbon. The gas is supplied around the specimen through a pipe and overflows into the vacuum of microscope column through the two platinum apertures on either side of the ribbon. The overflows gas from the specimen chamber is pumped out seperately from the evacuation system of main column. The minute hole in the ribbon and platinum apertures on either side of the ribbon are set to enable the passage of electron beams. The specimen stage can be taken out from the vacuum of electron microscope column through an air lock system without breaking down the vacuum. Some observations of gas reaction processes at elevated temperature by using the present device are presented.
Centrifugal Effects in Magnetohydrodynamic Pressurization of Liquid Metal Bearing
Authors: Kapur V. K.
Published: November 2005

In the present analysis, the centrifugal effects in magnetohydrodynamically lubricated thrust bearing due to radial magnetic field and axial pinch are considered in part 1 and part 2 respectively. The results for load capacity and flow rate for both cases have been discussed.
A Method of the Determination of Lattice Constants from Single-Crystal X-ray Photographs
Authors: Okazaki Atsushi , Tsukuda Noboru , Iwanaga Hiroshi , Kawaminami Masaru
Published: November 2005

A graphical extrapolation method from single-crystal X-ray photographs was used by Farquhar and Lipson to determine accurate lattice constants of an orthorhombic crystal. An extension of the above method to the case using shorter wavelength radiations such as MoKα is discussed. The difficulties due to the use of such radiations,i.e.low intensities of the Bragg reflections at high angles and a high background, are obviated with the help of a simple attachment to an ordinary single crystal oscillation camera. This technique is also useful for longer wavelength radiations such as CuKα. The application is made to an orthorhombic crystal, sodium nickel double fluoride NaNiF3. The present method will be particularly effective for the crystal with small lattice constants and/or with low symmetry. The method is compared with that using a back-reflection Weissenberg goniometer.
A New Method of X-Ray Diffraction Topography Using Monochromatic Divergent Beams Made by a Curved Crystal
Authors: Kohra Kazutake , Takano Yukio
Published: November 2005

A new method of X-ray diffraction topography is proposed, in which monochromatic divergent beams made by a curved crystal are used as the incident beam and diffracted successively from different positions of the specimen crystal by oscillating it.
The method is simple in mechanism and easy in experimental procedure. As a remarkable merit, a topograph of fairly high resolution and contrast is obtained from the whole region of the specimen even if it is heavily distorted. Some reflection as well as transmission topographs from a LiF crystal and a Si wafer locally coated with oxide film are shown and compared with those taken by the Lang method. A modified use is also described in which the specimen and photographic plate are rotated step-wise and by which information on the relative misorientation of various parts of the specimen is given.
Metallic Mesh Bandpass Filters and Fabry-Perot Interferometer for the Far Infrared
Authors: Sakai Kiyomi , Fukui Takashi , Tsunawaki Yoshiaki , Yoshinaga Hiroshi
Published: November 2005

This paper describes optical properties of thin electroformed metallic meshes in detail. Since the transmittance shows the bandpass character around the wavelength near the grid constant, metal mesh can be used as a bandpass filter. The reflectance is high in the wavelength region longer than three times the grid constant and the absorptivity is very low. These optical properties are suitable for reflectors of the Fabry-Perot Interferometers (FPI's) for the far infrared. Authors fabricated two types of FPI's; flxed type and tunable type. The absorption spectra of atmospheric water vapour between 100 and 400 µ and CO gas between 350 and 650 µ were scanned with the tunable FPI. Resultant resolving power of about 20 was obtained at 250 µ. Moreover, light flux which a FPI can utilize in the limited area of the light source and the detector was discussed.
Effect of Lubricant Inertia in Bearings
Authors: Agrawal V. K.
Published: November 2005

The inertia effects in squeeze film between two curved surfaces and externally pressurized bearing with a converging lubricant film are considered. It is shown that lubricant inertia for squeeze film bearing increases the load supporting capacity and decreases the squeeze. For externally pressurized bearing it is found that there is a negative contribution to the load supporting capacity by inertia forces.
Electron Microscopic Observation of Oxide Crystals Grown on Thin Film of α-Brass at Elevated Temperature
Authors: Ishii Makoto , Hashimoto Hatsujiro
Published: November 2005

Electrolytically-thinned α-brass foils containing dislocations, stacking faults and grain boundaries are heated at the temperatures between 200°C and 600°C in the air pressures between 1×10-4 Torr and 760 Torr in order to investigate the relation between the crystal imperfections and the oxide crystals formed on the surface. It is observed in the electron microscopic images that the particles of ZnO, Cu2O and CuO are formed on the surface of the specimen corresponding to heating conditions without any special relation to the imperfections in α-brass. It is also observed that hexagonal or irregular shaped thin regions are formed in the specimen by the evaporation of α-brass in the air pressures below 4 Torr at above 400°C. When the specimens of a few microns in thickness are heated, the needle-shaped zinc oxide crystals grow on the surface of α-brass with the axis of [100]. Sometimes drop-like particles are formed on the walls and at the tips of the needles. The evaporation mechanism of α-brass during oxidation and the role of drops to the crystal growth of needles are discussed.
Least Squares Analysis of Hall Data and Donor Levels in Gallium Phosphide
Authors: Toyama Masaharu , Unno Kazumi , Naito Makoto
Published: November 2005

The least squares method was applied to analysis of Hall data in n-GaP crystals doped with tellurium, and various possible level schemes of the donor, including valley-orbit interaction, were examined. From a detailed investigation of standard errors for the obtained parameters, a six-valley structure was shown to be the most probable model of the conduction band. Valley-orbit splitting energy, that is, the difference between the ground singlet donor level and the excited quintet level, was determined for various samples. The average of the splitting energies over the samples studied is (63±23) meV, in agreement with a theoretical prediction within the limit of errors.
A Criterion for Negative Resistance in Long Diode
Authors: Iida Masamori , Nojima Susumu
Published: November 2005

A graphical method of obtaining a current-voltage characteristic in long diodes is given and a criterion for occurrence of current controlled negative resistance in such diodes is proposed. The criterion is applied to negative resistance due to mobility modulation. Contributions of concentration and depth of level of deep impurity to this mechanism are investigated numerically.
Electronic Processes in Residue Compounds of Graphite Nitrate
Authors: Hishiyama Yoshihiro , Ono Akio , Inagaki Michio , Tsuzuku Takuro
Published: November 2005

By means of the X-ray diffraction, residue compounds of graphite nitrate prepared from a pyrolytic graphite have been found not only to indicate the interlayer spacing rather smaller than that of pure graphite but to show the three extra reflections representing a super-lattice structure something alike the third-stage compound. The investigation of electrical resistivity, Hall coefficient and magnetoresistance as functions of temperature and magnetic field intensity has revealed that the electronic structure becomes more metallic-like with increasing concentration of intercalated nitrate ions.
Based on these observations, an appropriate model has been considered for the Brilloin zone structure; the hexagonal pillar for the host graphite is horizontally sliced by several subboundaries so as to accomodate the super lattice structure. The contraction of interlayer spacing seems to be explained in terms of the interaction between the Fermi surface and the zone boundary surfaces in reciprocal space.
Criterions for the Assumptions of Thermal Equilibrium of Interstitial Atoms and of Vacancies in Dissociative Diffusion
Authors: Yoshida Masayuki
Published: November 2005

Basic equations for dissociative diffusion are non-linear. To solve them analytically, it is usual way to assume that interstitial atoms or vacancies are in thermal equilibrium. To obtain a criterion for the assumption, the basic equations are approximated by linear equations when concentrations of substitutional atoms, interstitial atoms and vacancies come near to their thermal equilibrium values. It is found that the thermal equilibrium concentration as well as the diffusion constant is an important factor for the criterion.
Effect of Ultrasonic Vibrations on Diffution in Brass-Copper Couples
Authors: Attia E. A. , Shyne J. C.
Published: November 2005

Brass-Cu couples were ultrasonically vibrated while undergoing diffusion anneal at 600°C, and the microprobe analyser was used to scan the diffusion profile. A comparison of the diffusion penetration curves in an insonated sample and a sample receiving only diffusion anneal showed a slight decrease in Zn concentration in the Zn rich region, which is thought to be due to Zn evaporation at microcracks produced by insonation. The experimental evidence suggests no measurable influence of insonation on the diffusion rate.
Low Temperature Characteristics of a Ni-Cu-Co Ferrite Magnetostrictive Vibrator
Authors: Shibayama Kimio , Karasawa Shinji
Published: November 2005

Electromechanical properties of a magnetostrictive vibrator made of Ni-Cu-Co ferrite are investigated over the temperature range 20°C∼-269°C. Variation of the resonant frequency is very small over the range 20°C∼-120°C, but the mechanical Q at resonance greatly decreases near -100°C. The decreases may be due to the lagging of magnetic flux, in which electron migration is related.
Theoretical Analysis of New Rheometers
Authors: Yamamoto Misazo
Published: November 2005

The strain and stress distributions in the sample contained in two new rheometers, the Orthogonal Rheometer and the Balance Rheometer, are discussed. In these rheometers we can measure the complex modulus as the constant force acting on the circular plate (the Orthogonal Rheometer) or as the constant torque acting on the rotational driving shaft (the Balance Rheometer). Although our discussion is restricted to linear viscoelastic materials, any special constitutive equation does not need to be used. The driving torque for the steady rotational motion of the apparatus is also calculated.
A Goniometer Head of the Polar Coordinate System and the Application to the Diffractometer Experiment
Authors: Niimura Nobuo , Shimaoka Kohji
Published: November 2005

A one-arc goniometer head has been designed for a neutron diffraction experiment using a heavy cryostat. This is easily accomplished with the one-arc goniometer head as the mechanical construction is considerably simpler than the conventional two-arc system. The practical application to diffractometer experiments has been found to be very simple.
A Q-Switched CO2 Laser with Absorbing Gas in the Laser Cavity
Authors: Ohtsuka Yoshihiro , Yoshinaga Hiroshi
Published: November 2005

Properties of resonantly absorbing molecules have been experimentally investigated by making use of Q-switching techniques. In passive Q-switching operation achived by gaseous SF6, the output consists of groups with 8 to 9 passively Q-switched pulses. The time between the groups is about 130 µs and pulse repetition time in a group is about 10 µs. In mechanical Q-switching operation, gaseous SF6 or C2H4 produces radiation subpulses which may be due to a series of 2 π pulse excitations to the molecules or due to superradiance from the excited molecules. The Q-swiched pulse becomes narrow with increase in pressure of the absorbing gas. The second giant pulse close by the first is generated to probe time-behavior of the molecules excited by the first pulse. The results indicate that thermal behavior of the molecules seems to continue over hundreds of microsecond when excited by irradiation of the Q-switched pulse.
Contribution of Obliquely Scattered Electrons to the Irradiation under the Scanner Window
Authors: Okabe Shigeru , Tabata Tatsuo , Tsumori Kunihiko , Ito Rinsuke
Published: November 2005

Directional distribution of electrons has been investigated for the case where they impinge on the sample after passing through the scanner window. A simple theoretical treatment to estimate the fractions of oblique electron flux is given. An experiment has also been made by using electrons of energies 1.5–8 MeV from a Van de Graaff and a linear accelerator. The calculated and the observed results have shown a moderately good agreement, It is to be noted that the contribution of the oblique flux with angle of incidence greater than 5° is about 15–65% under a typical irradiation geometry.
An Ion Microprobe Analyzer
Authors: Nishimura Hiroshi , Okano Jun
Published: November 2005

An ion microprobe mass analyzer was constructed for the analysis of solids. A beam of argon ions was used as a probe. The current and the diameter of the probe were 10-7 A and 0.25 mm respectively. A double focusing mass spectrometer was used to analyze the mass of the secondary ions. The mean radii of the ions in the electric field and in the magnetic field were both 10.0 cm. The deflection angles in these fields were 63.6° and 90° respectively. A Cu-Be secondary electron multiplier followed by a d.c. amplifier was used as an ion detector. Some characteristics with the variation of the peak height due to the change of the surface conditions were clarified. The relative sensitivities for Ti, V, Cr, Mn, Fe, Co, Ni in an iron alloy were determined. The detectable limits for boron in silicon and for chromium in iron were estimated to be 5 ppm and 1 ppm respectively. The distributions of nickel and chromium in the iron meteorite, Odessa, were briefly studied.
A Rotational Viscometer Capable of Precise Measurement at Very Low Rate of Shear
Authors: Yamagata Yasuji
Published: November 2005

A rotational viscometer with high accuracy at very low rate of shear (0.05 1/s) is constructed. It is a viscometer of free suspension type which is devised so as to reduce the influence of surface tension and the error due to excentricity. The expected error of the measurement can be so small as 0.02%. By means of this apparatus an anomaly of dip type in the curve of η
s
p
/C vs. C for highly diluted solutions (η
s
p
≃0.05) of polystyrene (mol. wt. 9.7×104) in toluene is observed. For the same dilution of DNA in water with 0.1 mol. NaCl an anomaly of peak type is observed. These anomalies are quite similar to the anomalies Cragg and Bigelow have observed in ternary systems and interpreted as the effect of critical concentration.
Flow Properties of Powder III
Authors: Taneya Shin'ichi
Published: November 2005

When glass granules coated with various amounts of oleic acid are packed into the annular space between two rotating coaxial cylinders, they exhibit the so-called plug flow around the inner cylinder. Theoretically, we have established a method of measuring the internal friction coefficient and cohesive force of loosely packed powder by means of a rotating coaxial cylinder rheometer. The internal friction coefficient of the used granules, obtained by this method was approximately 0.30, which agreed with that obtained by the shearing box method. Furthermore, the cohesive force of the granules obtained by the coaxial cylinder method is generally smaller than that obtained by the shearing box method. It may be considered that this is due to the fact that in the latter method the granules are compressed by the given load.
Hydromagnetic Noncyclic Squeeze Films in Journal Bearing with Radial Magnetic Field
Authors: Agrawal V. K.
Published: November 2005

A theoretical study is made of noncyclic squeeze films in full and half journal bearings of infinite length between two insulating surfaces in the presence of radial magnetic field. It is shown that the time of approach increases with the large Hartmann number. Further it is seen that the increase in the time of approach is much for large values of the Hartmann number whereas the increase in the time of approach is very small for small Hartmann numbers.
Electronmicroscopic Observation of Print-Out Effect on AgBr Crystals Obtained from Low Sensitive Photographic Plate
Authors: Iijima Sumio
Published: November 2005

The print-out effects due to xenon light illumination were studied electronmicroscopically in the temperature range from room temperature to 250°C on comparatively perfect silver bromide crystals obtained from the low sensitive photographic plate. As a result, it was found that a few pits appeared on the edges of the grains differing from the case of the grains obtained from the SSS photographic film already reported1). Triangular patterns1,2) hardly appeared on the grains at room temperature -250°C. Various silver protrusions bounded almost with (100) crystal surfaces appeared on the grains at 90°C–160°C. Silver whisker grew the grains at 90°C–160°C exposed to xenon light in vacuum. The whisker had two twin planes and its axis was always <110> direction, and also its crystal orientation is parallel to that of its mother crystal. It was confirmed that this whisker grew by the root growth mechanism.
Moiré Patterns Appearing in the Electron Microscopic Images of Grain Boundaries
Authors: Hashimoto Hatsujiro , Kodera Minoru
Published: November 2005

Intensity distribution of moiré patterns appearing in the electron microscopic images of interfaces such as twin, precipitation-matrix and small angle tilt boundaries has been discussed by the dynamical theory of electron diffraction considering absorption of electron waves. The theoretical conclusions, which show that the contrast of the patterns varies by the variation of the thickness of the crystal and the deviation from the Bragg angle, have been compared with electron microscopic observations. Some intensity anomalies appearing in the images of precipitation-matrix boundary have also been explained.
Growth Mechanism of Proper Tin-Whisker
Authors: Furuta Noboru , Hamamura Kenji
Published: November 2005

Growing processes of tin whiskers out of the tin phase of Al–Sn alloy were investigated. The particular distribution of angular bends observed in kinked tin whiskers and the formation of kinks are explained by the following two assumptions: (1) The incoherent boundary between the tin whisker and the parent material of tin phase corresponds to the so-called coincidence site boundary, and (2) on this coincidence site boundary whiskers cause a boundary-slip on account of a stress unbalance occurring at the root of whiskers during growth. Meanwhile, the crystallization growth concept proposed by Ellis, et at. (1958) is modified, and thereby the growing process of whisker is discussed theoretically. It is concluded that the growth rate of whisker is proportional to the strain energy in parent material; does not depend on its thickness; and the maximum thickness of whiskers is in inverse proportion to the strained energy. These conclusions are in good agreement with the experimental results.