Showing papers by "Nagoya University published in 1973"

Isotopic behaviour of sulphate oxygen in the bacterial reduction of sulphate

Abstract: The oxygen isotopic ratio of the sulphate remaining in the bacterial sulphate reduction has been found to be dependent on the oxygen isotopic ratio of the water in which the sulphate was reduced by bacteria. This finding is interpreted by a mechanism, in which the sulphate exchanges oxygen isotopes with the water through the intermediates in the bacterial reduction of sulphate into sulphide.

Formation of Ultrafine Metal Particles by Gas Evaporation Technique. I. Aluminium in Helium

Abstract: The appearance of smoke was studied by a video tape recorder. A typical smoke consisted of inner zone, inner front, outer zone and outer front. Smoke particles collected at different parts were studied by electron microscopy. They were large and often showed clear-cut habits in the inner front, while they were small and uniform in the inner and outer zones. The particle size varied with the gas pressure, evaporation temperature and position of collecting particles. The particles grow remarkably by coalescence where no metal vapour exists. All the experimental results on the size can be explained with an empirical rule that particles become larger when the nucleation starts in vapour of higher density.

Behavior of phenolic substances in the decaying process of plants: I. Identification and Quantitative Determination of Phenolic Acids in Rice Straw and Its Decayed Product by Gas Chromatography

Abstract: Phenolic acids in rice straw and its decayed product were surveyed and quantitatively analyzed by gas chromatography. 1) Thirteen kinds of phenolic acids in rice straw and its decayed product were identified. Besides p-hydroxybenzoic, vanillic, P-coumaric, and ferulic acids which had been already reported, nine phenolic acids were newly identified; these were benzoic, salicylic, syringic, protocatechuic, β-resorcylic, caffeic, sinapic, gallic, and gentisic acids. 2) A gas chromatographic analysis was applied to the micro-determination of major phenolic acids in rice straw and . the decayed products. The methanolic alkaline extracts from them were washed with ether, acidified, transferred into ether, trimethylsilylated, and injected into a gas chromatograph equipped with a silicon SE-30 column. The recoveries of p-coumaric, p-hydroxybenzoic, vanillic, and syringic acids were more than 90%, and ferulic and syringic acids were recovered at about 70%. 3) The content of each of the above described maj...

The Complete Classification of Fibres in Pencils of Curves of Genus Two.

Abstract: This article contains geometrical classification of all fibres in pencils of curves of genus two, which is essentially different from the numerical one given by Ogg ([11]) and Iitaka ([7]). Given a family π:X→D of curves of genus two which is smooth overD′=D−{0}, we define a multivalued holomorphic mapT π fromD′ into the Siegel upper half plane of degree two, and three invariants called “monodromy”, “modulus point” and “degree”. We assert that the family π is completely determined byT π, and its singular fibre by these three invariants. Hence all types of fibres are classified by these invariants and we list them up in a table, which is the main part of this article.

A simple rapid polychrome stain for epoxy-embedded tissue.

Abstract: Simple, fast, and reliable polychromatic staining of semithin sections from tissues fixed with glutaraldehyde and OsO4, embedded in epoxy resin, and attached to glass slides has been obtained. The staining solution was prepared a follows: dissolve monobasic sodium phosphate, 0.5 g, basic fuchsin, 0.25 g, and methylene blue, 0.2 g, in 15 ml of 0.5% boric acid solution and 70 ml of distilled water. Ten ml of 0.72% NaOH was added in the above mixture. Sections were stained for 4 to 5 seconds at 45 to 50d`C, and dried after rinsing. When staining is not sufficient, the procedure can be repeated. The method is reproducible and the results stable.

A note on Gorenstein rings of embedding codimension three

Abstract: Let A = R / , where R is a regular local ring of arbitrary dimension and is an ideal of R . If A is a Gorenstein ring and if height = 2, it is easily proved that A is a complete intersection, i.e., is generated by two elements (Serre [5], Proposition 3). Hence Gorenstein rings which are not complete intersections are of embedding codimension at least three. An example of these rings is found in Bass’ paper [1] (p. 29). This is obtained as a quotient of a three dimensional regular local ring by an ideal which is generated by five elements, i.e., generated by a regular sequence plus two more elements. In this paper, suggested by this example, we prove that if A is a Gorenstein ring and if height = 3, then is minimally generated by an odd number of elements. If A has a greater codimension, presumably there is no such restriction on the minimal number of generators for , as will be conceived from the proof.

Solid‐State Ionics: A New High Ionic Conductivity Solid Electrolyte Ag6 I 4 WO 4 and Use of This Compound in a Solid‐Electrolyte Cell

Abstract: A new high ionic conductivity solid Ag/sub 6/I/sub 4/WO/sub 4/ has been found in the system AgI-Ag/sub 2/WO/sub 4/ at ambient temperature. This compound has a silver ion conductivity of 0.047 (ohm.cm)/sup -1/ at 25/sup 0/C and an activation energy for conduction of 3.6 KCaL/mole between 20/sup 0/ and 293/sup 0/C. The transport number measurement using Tubandt's method shows that the transport number of silver ions in this compound is 1.00 within the experiment error. An Ag/Ag/sub 6/I/sub 4/WO/sub 4//I/sub 2/ solid-electrolyte cell shows an open-circuit voltage of 637 MV which agrees well with the value of 686.7 MV calculated from deltag degrees of the cell reaction at 21/sup 0/C. Characteristics of the solid-state cells using Ag/sup 6/I/sub 4/WO/sub 4/ as the electrolyte have been investigated. The phase diagram of the system AgI-Ag/sub 2/WO/sub 4/ has been determined also. 14 references.

Nonlinear Wave Modulation with Account of the Nonlinear Landau Damping

Abstract: The theory of nonlinear wave modulation in a collisionless plasma is developed on the basis of the Vlasov description, with particular attention to the nonlinear Landau damping process associated with resonance effects at the group velocity of the wave. Contributions from resonance particles, moving at the group velocity, change the nonlinear Schrodinger equation, derived in previous investigations, into the following equation, \(i\frac{\partial}{\partial\tau}\phi+p\frac{\partial^{2}}{\partial\xi^{2}}\phi+q|\phi|^{2}\phi+s\frac{\mathfrak{B}}{\pi}\int\frac{|\phi(\xi',\tau)|^{2}}{\xi-\xi'}\mathrm{d}\xi'\phi{=}0\), where φ(ξ,τ) is the small but finite potential amplitude, and τ and ξ are stretched variables in the “reductive perturbation” theory. \(\mathfrak{B}\) denotes a Cauchy principal part. Besides giving rise to the nonlocal-nonlinear term, the contribution of these resonant particles reverse the sign of the nonlinear coupling coefficient, q , relative to the value calculated neglecting their effect.

RELATION BETWEEN THE ACROSOME REACTION AND FERTILIZATION IN THE SEA URCHIN. I. FERTILIZATION IN Ca‐FREE SEA WATER WITH EGG‐WATER‐TREATED SPERMATOZOA. *

Abstract: Fertilization of sea urchin eggs fails to occur at a pH lower than 6.5. Analytical studies on this problem were made with Hemicentrotus pulcherrimus, Anthocidaris crassispina and Pseudocentrotus depressus. If the spermatozoa have been pretreated with egg water, eggs can be fertilized even at pH 6.5 and 6.0. The acrosome reaction is inhibited at a pH lower than 6.5. Intact spermatozoa fail to adhere to the fixed eggs in acidified sea water, whereas egg-water-treated spermatozoa adhere even at pH 6.5 and 6.0. From these results we infer that the failure of fertilization at pH 6.5–6.0 is caused by non-occurrence of the acrosome reaction, and that fertilization reactions other than the acrosome reaction, such as the binding and fusion of the gametes, are not inhibited in this range of pH. At pH 5.5, the spermatozoa become inert and fertilization is inhibited or suppressed, even though egg-water-treated spermatozoa are employed.

The Origin of the Ferroelectric Phase Transition in Ammonium Sulfate

Abstract: Long-wavelength lattice vibrations in ammonium sulfate are analysed group-theoretically, and symmetry coordinates of external modes belonging to the irreducible representation B 1 u , which is responsible for the phase transition from D 2 h to C 2 v , are obtained. They are composed of two groups; one is made of the purely translational and polar modes, and the other is made of the purely librational and nonpolar modes. Some peculiar properties of ammonium sulfate, including, especially, the very small value of the Curie-Weiss constant, are explained phenomenologically by a model in which a normal mode with a large component of a librational nonpolar mode admixed with a small contribution of a translational polar mode becomes soft.

Solid silver ion conductors

Abstract: Materials exhibiting high ionic mobilities in the solid state at room temperature have mainly been found in the silver ion conductors which are based on silver iodide. Though silver iodide is a low conductivity solid at room temperature, it exhibits high ionic conductivity at relatively higher temperatures. In order to stabilize this high conductivity phase of silver iodide at room temperature, the introduction of foreign cations or anions into the lattice of silver iodide has been attempted. In this paper, the various silver ion high conductivity solids are reviewed, together with those showing both high ionic and electronic conductivity.

Cytodifferentiation and proteoglycan biosynthesis.

Abstract: The connective and skeletal tissues are concerned chiefly with the formation and maintenance of bodily structure. In addition to a wealth of collagen or other fibrous constituents, these tissues contain in their intercellular matrix a specific group of polysaccharideprotein compounds ("proteoglycans**"), in which the polysaccharide moiety ("mucopolysaccharides") is composed of characteristic disaccharide units. A large body of evidence has now accumulated on the chemical characterization and structural configuration of the intercellular constituents. Certain aspects of the formation and deformation of the intercellular matrix and the role of cells in these processes have been studied also in some detail. Furthermore, a number of recent studies have called attention to the action of extracellular macromotecules on cells in a manner resulting in profound alteration of cell metabolism, growth, and various other properties. Our interest in the chemistry and metabolism of proteoglycans is an outgrowth of a curiosity about the mechanism of cytodifferentiation of cartilage cells

Propagation of Solitary Pulses in Interactions of Plasma Waves

Abstract: New solutions of solitary pulses in three-wave interactions are obtained, which were not given in the previous paper of this series. In those solutions, the wave of lower frequency has a shock-type envelope and behaves as a “pump” while the other two waves have the pulse-type ones. In addition, by considering two effects, linear translations of the waves and nonlinear interactions, a physical mechanism of formation of the solitary pulses is found. The theory is applied to the interaction among two Alfven waves and an ion-acoustic wave, which propagate along the external magnetic field,

On the Inner Repulsive Effect Due to the Pauli Principle between Nuclear Composite Particles

Abstract: The effect of the Pauli exclusion principle in the short range· part of interactions between nuclear composite particles is investigated in the case that there are some relative states which are not exactly forbidden but almost forbidden These "almost forbidden states" (AFS) are coupled only weakly t~ the incoming relative states Thus, the relative wave function is required to be approximately orthogonal to these AFS which are located in the inner region between composite particles This gives rise to a strong repulsive effect characterized by the almost energy-independent inner nodal behavior as observed in the case of a-a scattering However, at the energies characteristic of theAFS, the coupling to the AFS from the incident wave becomes very effective, and resonance-like contributions are brought about within the one-channel approximation With respect to this feature, the Levinson theorem is discussed § I Introduction The effect of the Pauli· principle is remarkably important in interactions between nuclear composite particles The interaction between a-particles pro­ vides us with a typical example The experimental phase shifts in a-a scattering are well reproduced by an energy-independent local potential at low and inter­ mediate energies?J, 2l As striking features of such a phenomenological potential, the inclusion of a strong repulsive core with a radius of about 2 fm is required for the relative s and d states·, and the attractive part outside the core is system­ atically dependent on the angular-momentum (l) By calculations with the re­ sonating group method applied· to a-a scattering,8l it has been shown that the eff·ect of the nonlocality originating from the antisymmetrization is completely responsible for the above features of the a-a phenomenological potential The presence· of the repulsive core can be understood as a result of· the almost energy-independent inner nodal behavior of the a-a relative wave function,'h 6) since the outermost nodal point coincides well with the radius of the repulsive core in a wide region of energies It should be noted ·that the inner nodal bee havior is not due to the -existence of any bound states 6 l A simple picture comprising such important aspects obtained by the res

Precise measurement of plastic behaviour of mild steel tubular specimens subjected to combined torsion and axial force

Abstract: In the present paper, as an investigation for obtaining detailed information about the plastic behaviour of real materials, precise measurement of plastic deformation of thin-walled tubular specimens of initially-isotropic mild steel was performed under combined loading of torsion and axial force having trajectories consisting of two straight lines at a constant rate of the effective strain. From the experimental results, it is found that the effect of the third invariant of the strain tensor appeared even for proportional deformation consisting of torsion and axial force. Moreover, it may be seen that the effective stress drops suddenly with increasing effective strain, and coaxiality between the stress deviator and the plastic strain increment tensor is seriously disturbed just after the corner of the strain trajectory. However, these local disturbances are recovered along the second branch of the trajectory. The effect of the third invariant of the strain tensor was eliminated from the experimental results by the introduction of the modified local stress space for isolating the influence of anisotropy due to the deformation history. This permits a systematic evaluation of the influence of anisotropy for various types of combined loading.

Absolute Calibration of Solar Radio Flux Density in the Microwave Region

Abstract: The absolute calibration of solar radio flux density in the microwave region, which showed considerable discrepancies until 1966, has become completely uniform through international cooperative work. A complete history is described to avoid confusion, and correction factors are derived to convert the published values into absolute values for long series of routine observations. It is also shown that the most reliable calibration can be made by using a large pyramidal horn and by using sky and room temperature as calibration standards.

Thermal Switching in Chalcogenide Glass Semiconductors

Abstract: The current-voltage characteristics in off state and the switching phenomena are investigated. The results can be well explained by a thermal model based on the self joule heating of the sample. The results are summarized as follows: (1) I-V characteristics in off state can be normalized over a wide range of temperatures and voltages, and the resulting normalized current has an ohmic and an exponential regions. Calculations based on the thermal model agree very well with the experimental I-V characteristics. (2) From the dependences of the switching threshold voltage upon temperature and resistivity, it is found that the switching can be initiated by a thermal process.