It is believed that scale pattern of fish, it's otolithes, backbones and so on contain ecological informaton representing such as the the rate of growth, physiological state of fish, the river stocks and others. The scale pattern characters have, thus, been utilized for the determination of the fish age and the river stock to presume the amount of such marine resources as salmons captured in the ocean. At present, however, the measurement of these scale pattern data is performed by means of visual and manual methods by the professional specialists. In the present paper, reported is a new method for estimating the age of chum salmon using its scale pattern data optically read.
A scale of chum salmon is a small object having a diameter of approximately five milimeters. The center of the scale pattern is referred as a “focus”, and annual rings like those found in the stump of a tree are observed surouding the focus. In the scale pattern, the two kind of belting zone of rings are seen, one of which is referred as “resting zone(or winter zone)” and the other “growth zone(or summer zone)”. The former is the part in which the crculus interval is narrow, showing the growth rate is very slow, and the latter the part in which the interval is wide, indicating the favourable growth of of scale compared with resting zone.
The number of the resting zone is regarded equal to the age of the fish. The authors developed and propose a new mathematical function, which may be defined as “Tendency Density Function” by which the number of the resting zone can easily be extaracted and measured. The parameters to be measured are the number of circuli, (N), and the intervals between circulus, (Xi), in milimeters along the line drawn outward from the focus of the circuli pattern.
In the present analysis, the circulus and intevals data on each of ten lines for one sample were measured so that the data obtained might represent the information being involved over the entire plane of scale pattern. From this point of view, the authors designated these as the “two dimensional data”.
Conclusion;
The results of the age determination by the above mentioned means are as follows; The ages measured by the proposed method coincided with those measured by the visual method on approximately ninety (90) percent of the sampled fish. It was demonstrated that the proposed “Tendancy Density Function” was extremely useful for the purpose of estimating the fish age from the scale pattern information.

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So far, pure Mn₃O₄ as a raw material for Mn-Zn ferrites has been synthesized by a hydrothermal reaction of H₂O and Mn. But, this method was costly because it needs high temperatures above 120°C and high pressures above 3kg/cm². And so it was tried that the pure Mn₃O₄ might be synthesized at not more than 100°C and under an atmospheric pressure by addition of ammonium salts or amino-acids to water with Mn.
Firstly, in N₂ atmosphere, the formation rates of Mn(OH)₂ were measured at various temperatures when ammonium salts or amino-acids (0.05-0.5mol/l) were added into water with Mn. Secondly, the reactions were carried out under an oxygen or air atmosphere and the reaction rates and the reaction products (Mn₃O₄) were examined.
As the results, it has found these reaction rates were dependent on the hydrogen-ion concentration, the oxygen pressure, the variety and concentration of the additions. On this reaction, Mn was oxidized by H⁺ and O₂, and the additions, ammonium salts or amino-acids, catalyzed this reaction. These additions complexed with Mn²⁺ which was produced by the redox-reaction between water and Mn, and decreased the activity of Mn²⁺. And also, the reaction finished for the almost same hours even when the filtrate is used again many times.
By the addition of ammonium salts or amino-acids, it has become easy to synthesize Mn₃O₄ from metal Mn at not more than 100°C, under an atmospheric pressure and within some hours. The Mn₃O₄ obtained by this reaction was of high pulity, so may be applied to the additions for ferrites.

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The monodispersed titania particles were prepared by the hydrolysis of titania tetra-ethoxide in a alcolic solution. The effect of heat treatment and hydrothermal treatment on the obtained monodipersed titania particles were examined by means of TEM, XRD, TG-DTA and BET.
The obtained titanis particles was amorphous titanis was crystallized to anatase type at 400°C, and was transfered to rutile type at 900°C. By autoclave treatment, the transfer of anatase type from amorphous titania was occurred at lower temperature as 150°C, and a part of titania particles were broken at higher temperature as 250°C.

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Since it was reported that the D-D nuclear fusion might be occurring by the electrolysis of heavy water in a room temperature, so many scientists have been trying to verify the reaction.
In this study, we used some kinds of hydrogen-absorbing metal, namely Pd, Ti, TiNi_0.5, TiNi, ZrV_1.8Ni_0.2 and ZrV_1.5Ni_0.5 as the cathode, and measured continuously γ-ray emission by γ survey meter accompanying the electrolysis in LiOD/D₂SO₄-D₂O solution. At the same time, the quite same experiment was carried out in an ordinary water containning LiOH or H₂SO₄ as the reference standard. These cathodes were mainly the sintered and the anode was always Pt-wire. The electrolysis was carried out by a constant current method till the electrode was saturated by D or H. And also, degrees of the charged H or D into metals were measured by using another cell.
For the heavy-water electrolysis, meaning γ-ray emissions were observed in any case of these metal electrodes. But, in the cases of Ti-Ni and Zr-V-Ni system metals which have larger hydrogen-absorbing abilities than Pd, their γ-ray emissions, that is, the fusion rates were few times as much as that of Pd. From start to finish of the electrolysis, the fusion rate was not very dependent on the deutrium concentration in the electrode in every case. And so, the fusion rate per deuteron pair per second decreased with the lapse of electrolizing time. From these results, it was considered that the fusion might be occurring in a deuterium diffuse layer or a reaction zone where the metal phase is transforming to the deuteride phase and micro-cracks are developing because of the lattice expansion.

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Thin oxide layers are formed on metal surfaces at ambient temperatures even at low oxygen residual gas pressures in vacuum systems or in inert gas atmospheres. Such oxide layers impede or prevent hydrogen absorption at ambient temperatures. To gain a fundamental understanding of the reaction mechanisms, reaction kinetics of hydrogen and oxygen absorption by titanium films were measured by using the Wagener volumetric method. Theoretical approaches to explain the effects observed are discussed. At the initial stage of the oxidation, ion transport by the Mott potential produced by electron tunneling controls the reaction probability. The pressure dependence of the hydrogen absorption rate indicates that the rate determining step of the reaction is either the dissociation of hydrogen molecules on the surface or the permeation or diffusion of hydrogen atoms in the film.

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Most intelligent materials are brittle. From the engineering point of view, it is just important to evaluate the fracture toughness. K_IC is a standerd value to evaluate the brittleness. However, it is difficult to prepare (form) test specimens. Vickers hardness tester is a good tool to know many mechanical propaties without fracture. In this paper, we introduce evaluate methods of fracture toughness for brittle materials by means of Vickers hardness tester. Indentation fracture (IF) method is easy to detarmine K_IC to measure crack length around the indentation, load, diagonal and Young's modules. On the other hands, we have suggested a new method to evaluate brittleness by means of critical deformation energey (E_f). E_f is calcurated by critical load (P_f) and critical diagonal (d_f) only. This method is useful to evaluate brittleness of small or thin specimens.

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Ductility evaluation of high T_c Bi-Pb-Sr-Ca-Cu-O is quantitativelty perfomed with a Vichers' indentation method. The liquid-quenched (L.Q.) glassy oxide which doesn't show the superconductivity above 4.2K is brittle. On the other hand, the high Tc crystal oxides are ductile. It is especially that the sintered sample before L.Q. shows ductility more higher than the crystallized sample after L.Q.

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The residual stress induced in ceramic-metal joints bonded at high temperature will strongly influence the strength of joints. The residual stresses induced in a silicon nitride to carbon steel joint plate were calculated by the three-dimensional thermo plastoelastic stress analysis using the finite element method (FEM), and the result was compared with the values measured by x-ray diffraction. The three-dimensional analysis shows that the residual stress concentrates and distributes three-dimensionally at the ceramic-metal interface. The measured residual stresses almost agreed with those calculated by the three-dimensional FEM, but they differed greatly from the values by the two-dimensional FEM. The large tensile residual stress σ_x in the axial direction at the interface in the silicon nitride would have the strongest influence on the strength of the joint.

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When the X-ray emission from a finite temperature plasma is analyzed, we require detailed information about an atomic structure of the plasma under various plasma conditions. The spectroscopic diagnostics using the X-ray emission from the plasma is a powerful tool to estimate the plasma parameters.
The objective of this paper is to present the results of calculation of electronic conditions in a finite temperature plasma. This is achieved by the following two methods: [1] the finite temperature Hartree-Fock method (FTHF) in which the Dirac equation is solved by using the Runge-Kutta method, and [2] the average ion model (AIM) with the simple Coulomb potential and More's shielding constant 1). In the FTHF, the potential energy for electron is estimated from the self-consistent electron density with the ion sphere model. We employ this potential in solving the Dirac equation. In the AIM, only one fictitious ion having Z exists. The average ion model has been widely used for analyzing the radiation from a laser irradiated high-Z target. In the AIM, the population N_{n, z} of each ion charge state z in the nth level is generally required to calculate X-ray emission from the plasma. However, for a high-Z plasma, the equation for this population is rarely solved. Consequently, in the AIM, N_{n, z} is averaged over Z and it is sufficient to solve only the equations for the level population P_n of an averaged atom.
We investigated the electronic conditions of finite temperature plasmas by using the FTHF and AIM methods. In the present paper, calculation results are presented for the Al₁₃ and Fe₂₆ atoms at T=100eV and the solid density. The results obtained by the FTHF method agrees with Rozsnai's results 2). We have also calculated the energy of bound electrons with the population from the FTHF calculations and with More's shelding constants 3); however, they are not in good agreement with the FTHF results. This suggests that we have to determine More's shielding constants more precisely.

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A new dispersion strengthened die casting alloys, Al-5Ni-5Mg (wt%) has been developed. It exhibits improved ductility when compared to the conventional Al-Si based die casting alloys such as Al-8Si-3Cu (ASTM 380). The new alloy has tensile elongations of 11%, which is significantly better than that of the Al-8Si-3Cu alloy. The measured tensile strengths of new alloy is 15% higher than that measured for the conventional alloys. The measured Charpy impact strengthof new alloy is 300% higher. The new alloy is close to binary eutectic compositions. Because of the relatively rapid solidification of the high pressure die casting process, this alloy contains a fine uniform dispersion of needle shaped Al3Ni particles. The Mg in solid solution with the Al matrix additionally strengthens the alloy.

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It is found that an electron can be efficiently accelerated by a simple system which is composed of a plus plane electromagnetic (EM) wave and a astatic magnetic field. In this system the direction of the magnetic component of the EM wave is pa rallel to that of the static fields. Initialy an electron is positioned in front of the pluse plane EM wave and the electron speed is less than the speed of light(c). The pulse plane EM wave travels across the static magnetic field with the speed of fight(c). Therefore, the pluse EM wave catches up with the electron and leaves it behind. Without the static magnetic field in the system, the electron would not be able to absorb the wave energy because of the symmetry of the EM wave. However, because the static magnetic field breaks the symmetry of the EM wave in the system, the electron can absorb the wave energy and be efficently accelerated in the direction of the electic component of the of the EM wave. We have obtained the optimal magnitude for the static magnetic field and the final γ by a simple analysis.
The single particle analyses and the simulations also show that this system ones well for a high-energy electron acceleration and the simulation results agree with the analytical results.

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A new type of magnetized filamentary plasma, whose radius is less than the ion Larmor radius, has been successfully produced by utilizing a TP-D type discharge apparatus. We call this new type of plasma a “string-plasma”. A preliminary analysis has revealed that the movements of the majority of ion guiding centers in a steady-state string-plasma are restricted in the vicinity of the axis of the plasma column. This situation can be viewed that the ions are trapped in a radial electric-potential-well which is a result of the charge separation between an electron “string” confined by an axial magnetic field and the ion themselves gyrating around this electron string. Therefore, one can consider the string-plasma as a “boundary-like” plasma that still preserves an overall charge neutrality.
The device to produce a string-plasma is divided into two regions: a discharge region which is a high pressure TP-D type arc chamber and a low pressure experimental region. Two regions are differentially pumped out by means of a narrow path provided by a bunch of cylindrical electrodes (floating electrodes and an anode) in the discharge region. A plasma produced in the discharge region is compressed by a point cusp and by strong radial-electric-fields formed in the region of the floating electrodes. Because the ion Larmor radius is larger than the electron Larmor radius, the floating electrodes tend to be positively charged up, resulting in inwardly-directing, strong radial-electric-fields which serve to radially confine thermalized ions. As a result, the radius of the plasma flowing into the experimental region through a small cylindrical anode and floating electrodes (typically 2mm inner diameter) becomes less than the ion Larmor radius. Perpendicular ion motion of the string-plasma measured by a Katsumata probe is found to be uni-directional, corresponding to the direction of ion cyclotron motion.
Understanding physics of boundary regions of high-β plasmas is very important for research of magnetic confinement fusion, where β is the ratio of the plasma kinetic pressure to the energy stored in magnetic field. Since ions are gyrating around the same axis in a string-plasma, the effect of ion diamagnetizm becomes important as the plasma density is increased. The consequence is that the magnetic field strength is effectively reduced inside the plasma column, realizing a similar situation to that of boundary regions of high-β plasmas.

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An ion cyclotron resonance scheme can be utilized to separate different masses in a string-plasma. A string-plasma is a magnetized filamentary plasma whose radius is equal to or less than the ion Larmor radius. We have recently succeeded in producing such a plasma by utilizing a TP-D discharge apparatus. Our analysis has revealed that the movements of the majority of ion guiding centers in a steady-state string-plasma are restricted in the vicinity of the axis of the plasma column. This situation can be viewed that the ions are trapped in a radial electric-potential-well which is a result of the charge separation between an electron “string” confined along an axial magnetic field and the ions themselves gyrating around this electron string. One can consider the string-plasma as a “boundary-like” plasma that still preserves an overall charge neutrality.
The peculiar properties of this string-plasma can be useful for various interesting applications especially in materials science. In particular, a mass separation technique using a string-plasma is described. A set of rf electrodes are placed in such a way that they can produce a rotating (in the direction of ion gyration) electric field in the string-plasma, resulting in the efficient selective energyzation of resonant ions (whose cyclotron frequency matches the rf frequency). The essential point is that resonant and nonresonant ions can be physically well separated since all ions are gyrating around the same axis, one of the important features of the string-plasma. This allows one to easily separate different mass species using a simple device. An impurity species can be selected as a resonant species. Applying the ion-cyclotron-resonance mass-separation technique several times along the string-plasma, undesirable ion species can be eliminated from the plasma. Consequently, it becomes possible to produce an impurity-free, low-energy ion beam or a plasma stream.

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A growing process of the depositing film by a plating method is similaly same with that by a dry process such as an evaporation process and a sputtering process. And the structure of deposited film by the plating method is substancealy same as that of the dry process also. On this report, the growing process of the plating film is explained, and the factor on determination of the structure which is crystalline or amorphous is discussed. Further more the unique theory about it is presented by an anther. The theory is “the structure of deposited film is determined by the composition of the deposited film and by the formation temperature”. The theory is available to explain the growing process on both wet system and dry system and the structure of depositing film. Furthermore some functional materials prepared by the plating method is introduced.

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