Showing papers by "Waseda University published in 1973"

A new fla gene in Salmonella typhimurium--flaR--and its mutant phenotype-superhooks.

Abstract: An electron microscopic examination of eight non-flagellate strains of S. typhimurium revealed that an H1 (amber) mutant produced flagellar hooks and basal structures indistinguishable from those associated with the proximal end of normal flagella. No flagella-related structures were seen in strains with mutations in fla genes A, B, C, D, F, K or M. A mutant of a new fla complementation group, flaR, produced abnormal structures, termed “superhooks”, which resemble the hooks of normal flagella assembled end-to-end. The mutant locus, flaR, maps between flaM and flaAIII.

Elastic anomaly in (NH4)2SO4

Abstract: Measurements of the elastic compliance and electrostrictive constant of a (NH4)2SO4 crystal, together with the dielectric constant and spontaneous polarization, have been made. It is observed that there are anomalies in the elastic compliances and that the electrostrictive constants are of the ordinary order of magnitude. A phenomenological theory has been developed to analyse the experimental results, where an order parameter is introduced and its couplings with polarization and stress are taken into account. The anomalous temperature dependence observed in the dielectric constant, spontaneous polarization, spontaneous strain, and elastic compliance is explained in terms of the temperature dependence of the order parameter. The only exception is the shear component for which a further investigation might be necessary. Messungen des Elastizitatskoeffizienten und der Elektrostriktionskonstante des Ammoniumsulfates, (NH4)2SO4, zusammen mit der Dielektrizitatskonstante und der spontanen Polarisation, wurden durchgefuhrt. Es wurden Anomalien in den Elastizitatskoeffizienten und ein Wert der Elektrostriktionskonstante von normaler Grosenordnung gefunden. Eine phanomenologische Theorie wurde entwickelt, um das experimentelle Ergebnis zu analysieren, wobei ein Ordnungsparameter eingefuhrt wird und seine Kopplungen mit der Polarisation und der elastischen Spannung berucksichtigt werden. Die beobachtete anomale Temperaturanderung der Dielektrizitatskonstante, der spontanen Polarisation, der spontanen Deformation und des Elastizitatskoeffizienten last sich gut mit der Temperaturabhangigkeit des Ordnungsparameters erklaren. Nur die Scherungskomponenten bilden eine Ausnahme und machen eine weitere Untersuchung notwendig.

Theory of the Optical Property of Retinal in Visual Pigments

Abstract: Previous calculations on the π-electron system in retinal are refined in a more rigorous way Firstly, the σ-π interaction indispensable to derive the bond alternation is semiempirically determined from the first principle Secondly, the effect of a sufficient number of singly- and doubly-excited configurations are examined in CI calculation It is thus confirmed again that the wavelength of optical absorption maximum of retinal forming protonated Schiff-base binding is about 200 nm longer than that of retinal forming normal Schiff-base binding The concept of partially-protonated Schiff-base binding of retinal, which is a phenomenological description of the previous theory for the interaction of retinal with opsin, is also formulated by introducing the degree ( x ) of protonation, and the x -dependences of the wavelengths and oscillator strengths of optical absorption are calculated

The catalytic effects of the poly(vinylpyridine)‐ligand in the oxidative polymerization of phenols

Abstract: In order to study the catalytic effects of the polymer-ligand, copper-poly(vinylpyridine) (Cu-PVP) complexes were used as catalyst for the oxidative polymerization of phenols. The catalysis was discussed. The rate of the 2,6-dimethylphenol (XOH) polymerization catalyzed by the Cu-PVP complex was slower than that catalyzed by a Cu-pyridine complex. By the measurement of the kinetic constants, it was suggested that a bulky PVP ligand obstructed the coordination-step of the monomer and the electron-transfer-step from the coordinated monomer to the cupric ion. The polymerization of the mixture of XOH and o-cresol with Cu-PVP as catalyst was saturated at a higher conversion, and the yield and the molecular weight of the polymer obtained were larger than in the cases where the Cu-pyridine or the Cu-γ-picoline complex systems were used as catalysts. XOH is preferentially activated by the Cu-PVP catalyst because its oxidation potential is lower, thus the effect of the PVP ligand may be observed. XOH was polymerized by the swelled Cu-PVP complex as a heterogeneous catalyst in benzene or a benzene containing mixture of solvents. The catalyst was recovered by filtration in a high yield and re-used repeatedly. Cu-PVP complexes are relatively stable toward alkali because of their chelate structure. The polymerization was accelerated 3 to 5 times in alkaline solution, and the side-reaction was suppressed. Um die katalytische Wirkung des Polymer-Liganden zu untersuchen, wurden Kupfer-Poly(vinylpyridin) (Cu-PVP)-Komplexe als Katalysatoren fur die oxydative Polymerisation der Phenole eingesetzt. Der Katalyseverlauf wurde diskutiert. Die mit dem Cu-PVP-Komplex katalysierte Polymerisation des 2,6-Dimethylphenols verlief langsamer als die mit dem Kupfer-Pyridin-Komplex katalysierte. Aufgrund der Messung der kinetischen Konstanten wurde angenommen, das der raumfullende PVP-Ligand die Koordination des Monomeren zum Metall stort. Die Polymerisation des Monomerengemisches aus XOH und o-Kresol verlief in Gegenwart des Cu-PVP-Katalysators bei hoheren Umsatzen mit konstanter Geschwindigkeit. Die Ausbeute und das Molekulargewicht des erhaltenen Polymeren waren groser als in den Fallen, in denen Cu-Pyridinoder Cu-γ-Pikolin-Komplexe als Katalysatorsysteme verwandt wurden. XOH wird vorzugsweise mit dem Cu-PVP-Katalysator aktiviert, da das Oxydationspotential des XOH niedriger ist; dadurch wird die Wirkung des PVP-Liganden erfasbar.

Modified Dechanneling Theory and Diffusion Coefficients

Abstract: When energetic ions are incident along a low index crystallographic direction, their motions are well confined inside a channel. Due to a set of small angle collisions by electrons, lattice atoms, defects in the crystal and so on, the transverse ion momentum increases, and this leads to dechanneling. Since the Lindhard theory [1], the theoretical treatment of dechanneling has been developed by many authors [2–5] according to the steady-increase model or the diffusion model. Recently Bonderup et al. [3] and Bjorkqvist et al. [4] have shown that by the steady-increase model it is not possible to explain the experiments at higher dechanneled fractions.

Spectral Distribution of the Light Scattered from Rodlike Macromolecules in Solution. II. The Effect of Optical Anisotropy

Abstract: The theory of the spectrum of the light scattered from rodlike macromolecules presented earlier (H. Maeda and N. Saito, J. Phys. Soc. Jpn., 27, 984 (1969).) is extended to optically anisotropic rodlike molecules. The spectrum is shown to be the sum of an infinite number of Lorentzians. The forward scattering is shown to be free from the effect of translational diffusion. The numerical calculations for TMV solution are presented.

Dielectric Behaviour of Some Vinyl-Type Polymers in Dilute Solution

Abstract: Dielectric loss measurements using frequencies from 1 to 150 MHz were carried out on four vinyl-type polymers in dilute solutions (PVC, PpCS, PpBS, and PVAc in toluene, dioxane, and carbon tetrachloride) at temperatures from −23° to 60°C. The shape of the absorption curve is always asymmetric, irrespective of the kind of polymer, molecular weight of the polymer, solvent, and temperature. The relaxation time has no molecular-weight dependence. It does, however, depend on the solvent, and is approximately proportional to the solvent viscosity. The activation energy, ΔHA is 3.2—5.9 kcal/mol for each solution, and depends on that of the solvent viscosity, ΔHη, in the manner described by ΔHA=ΔHη+C, where C is a constant. C is proposed to represent the potential energy for the conformational change. It is also proposed that two relaxation mechanisms, a diffusion-controlled mechanism for segmental rotation and a site model, should be taken into consideration simultaneously in order to interpret the dielectric behaviour.

Complex Continuum Potential for Channeling

Abstract: Complex continuum potentials for channeling due to non-local inelastic scatterings are introduced. The relation between the complex continuum potential and the Yoshioka term for electron diffraction is studied. For an example, phonon excitations are considered in detail for numerical calculations of the imaginary continuum potential (absorption coefficient). The local diffusion constant for dechanneling theory is also discussed.

On the Models for Phytochrome Chromophore. IV

Abstract: On the stereoisomers of bilitriene with no ionic structure in their π-systems, their wavelengths and oscillator strengths of absorption are calculated by the ZDO approximation of the LCAO-ASMO-SCF-CI theory of π-electrons. The interaction of the π-systems with a point-dipole is also investigated using the stationary perturbation theory for degenerate states. It is thus shown that a stereoisomer of bilitriene with no ionic structure in its π-system can explain the observed absorption spectrum of P r , and that an interaction between such stereoisomer and a point-dipole is further necessary to reproduce the observed spectrum of P fr . The photoisomerization of a terminal pyrrole ring is also concluded to be probable for the origin of P r -P fr conversion.

Polyamine polymers from pyrrole, formalin, and amines by use of the mannich reaction

Abstract: It was found that pyrrole, one of the active hydrogen compounds, easily condensed with formalin and amine in the presence of acid catalyst to yield a new type of polyamine polymer containing pyrrole nuclei in the main chain of the polymer. This polymerization method was also confirmed to be applicable to the other active hydrogen compounds, such as N-methylaniline, acetone, malononitrile, and hydroquinone. The structures of the polymers obtained were determined by infrared NMR and elementary analyses. We named this reaction a Mannich polymerization and the polymers obtained the Mannich base polymer.

Strong coupling between proton and phonon in KDP

Abstract: The correlation function for the proton-phonon coupled system has been obtained b means of the retarded Green's function. The dynamic susceptibility and the internal energ are evaluated in a random phase approximation. Some discussion has been made on tb results by comparison with those obtained previously by others, in which the emphasis ha been laid on the isotope effects. As a result, it is found that the proton-phonon couplin is very large and then responsible for the isotope effects as well as the lattice instability. Die Korrelationsfunktion fur das gekoppelte Proton-Phonon-System wurde mit Hilfe de retardierten Greenschen Funktion erhalten. Die dynamische Suszeptibilitat und die inner Energie werden in der Random-Phase-Naherung abgeleitet. Die Ergebnisse werden diski tiert und mit denjenigen verglichen, die fruher von anderen erhalten wurden, und i denen insbesondere die Isotopeneffekte berucksichtigt wurden. AIs Ergebnis wird gezeig das die Proton-Phonon-Kopplung sehr stark und folglich fur die Isotopeneffekte und di Gitterinstabilitat verantwortlich ist.

Electrofocusing of partially purified bovine luteinizing hormone.

Abstract: Activity of luteinizing hormone (LH) was separated into two major components and an additional minor component by isoelectrofocusing of a partially purified bovine adenohypophysial preparation obtained by the gel filtration with Sephadex G-100. The components posessed the isoelectric point at pH 8.8, 8.3, and about 4.0, respectively. This result shows that bovine LH consists of two or three kinds of molecules with different isoelectric points.

Excitation of Trapped Electrons in SbSI

Abstract: The photoconductive and photo-diffusion effect of SbSI is investigated. The photocurrent and the short-circuit photovoltaic current depend not only on the photon energy but also on the polarization of the incident light. The photon energy showing the peak value of the photocurrent for the polarized light perpendicular to the c -axis is 0.05 eV higher than that for the polarized light parellel to the c -axis in both paraelectric and ferroelectric phases. The polarity reversal of the short-circuit photovoltaic current is observed. From the results, it is suggested that there is the trap level at about 1.9 eV below the bottom of the conduction band and that the maximum photocurrent at around 1.9 eV is induced by the excitation of trapped electrons, while the photocurrent at a higher photon energy is induced by the generation of holes.

“hydrated talc”-an alteration product of wollastonite by reaction with magnesium-bearing hydrothermal solution

Abstract: A clayey material consisting predominantly of the trioctahedral 2:1 phyllosilicate which is similar to talc rather than stevensite, with a basal spacing of 9.7 A, was found in hydrothermal-alteration products of wollastonite-rich skarn at the Akatani copper-iron mine, Niigata Prefecture, Japan, by one of the present authors (N. I.). The material occurs as a small pocket in the wollastonite-rich skarn, and is pseudomorphous after wollastonite. Field relations indicated that the small pocket is located in an intermediate subzone between inner talc and outer stevensite zones. Chemical analysis of the clay fraction less than 2, a leads to the following structural formula for the mineral in question per unit-cell-layer on the basis of O20(OH)4 anion unit; (Mg5.81 Mn2+0.40 Fe3+0.06) (Si7.73 Al0.15)O20(OH)4(Na0.02 K0.02)•EnH2O. X-ray diffraction, thermal and infrared absorption analyses revealed that the mineral in question is a variety less hydrated than stevensite, and may be named as \"hydrated talc\". Based upon the field relations, information on the formation temperatures of minerals from the mine obtained by means of fluid-inclusion thermometry, and the synthetic data for the system MgO-SiO2-H2O, the mineral in question was identified as an alteration product of the preexisting wollastonite at temperatures of 250•‹•`300•Ž by the action of magnesium-bearing hot water, which journeyed through a channel-way immediately before ore-formation and simultaneously dolomitized lime-

Effect of electrostatic field on the polymer chain in the quaternized reaction of polyvinylpyridine with alkyl halides

Abstract: In order to discuss the electrostatic-field effect on a polymer reaction, the quaternization of poly-4-vinylpyridine–benzyl chloride (system I) was compared to that of poly-γ-chloromethylstyrene–γ-picoline (system II). In these two systems, the reaction initially proceeded according to the simple second-order kinetics. However, after the degree of quaternization exceeded 20–30 mole-%, a deviation from simple second-order kinetics occurred. In system I negative deviation occurred, while in system II positive deviation occurred. These phenomena occurred even though the solvent or the initial concentrations of the reactants were changed. The reasons for these phenomena are given below. In system I, the quaternized pyridine nitrogens prevented the benzyl chloride from approaching the unquaternized pyridine nitrogens. However, in system II the free γ-picoline was attracted by the quaternized chloro-γ-methyl site. Furthermore, the point at which the deviation occurred was determined by the degree of chloromethylation. All these results suggest that the effect of an electrostatic field must be presumed in these two systems.

Size distribution of crystals from classified bed type crystallizer

Abstract: The concentration of particular size throughout the bed was experimentally studied on a fluidized bed of glass beads with an acrylic column of 50 mm diameter and 1000 mm height, and analyzed by the application of the axial diffusion model for particles of two sizes. From the experimental results, it was found that the axial distribution of void fraction might become that calculated by the assumption of perfect classification for the range of present conditions. The estimation method of size distribution of crystals from a classified-bed crystallizer is proposed on the axial diffusion model, using the relation between crystal size and bed height under the assumption of perfect classification in the author''s previous report. It is shown that the size distribution of sodium chlorate crystals from a test plant and sodium sulfate from pilot and industrial plants of this type agree with the calculated results from the model.

Morphometric classification of the neurosecretory granules in the rat pars nervosa.

Abstract: The distribution of the diameters of the neurosecretory granules in the rat pars nervosa (measured from electron micrographs taken at 40 000 × ) was compared among axons by nonparametric statistical methods and the axons were classified into five groups with median granule diameters of 143, 155, 167, 180 and 193 nm. We suggested that these five axon types carried different secretory substances contained in the pars nervosa.

Effect of Precipitates on Recrystallisation Temperature in Cu–Cr, Cu–Zr and Cu–Zr–Cr Alloys

Abstract: (at 350, 450, 500, 550 and 700°C), heavily cold worked and annealed at various temperatures were studied by the resistometric method, measurements of mechanical properties and transmission electron microscopy. No fine precipitates were detected at dislocations or sub-boundaries in the low temperature annealing stage, but fine precipitates, which retard recovery, must exist since electrical resistivity decreased during low temperature annealing. The mechanism of retardation of recovery is due to the binding of dislocation jogs by fine precipitates. In the high annealing temperature range, the growth of precipitates and crystal grains was observed by transmission electron microscopy and the effect of precipitates on the retardation of recrystallisation was also detected. The size of precipitates formed during tempering before cold working did not affect the recrystallisation temperature, because the precipitates were broken up by heavy cold work and were thus made a constant size.

Kikuchi patterns in the bragg case

Abstract: Kikuchi patterns in the Bragg case are investigated using the Yoshioka theory of diffraction, which includes the absorption effect described by the optical potential. The band-like and the line-like terms, which correspond to the band and the line terms of Kikuchi patterns in the Laue case, respectively, are obtained. In this case, the band termcannot be divided from the line term as done in the Laue case. Kikuchi patterns in the Bragg case are useful instruments in the study of solid surfaces. Comparison with experiment is discussed briefly to ascertain the existence of Kikuchi patterns in the Bragg case. Kikuchi-Diagramme im Bragg-Fall werden mit der Beugungstheorie von Yoshioka untersucht, die Absorptionseffekte einschliest, die durch das optische Potential beschrieben werden. Bandahnliche und linienahnliche Terme werden erhalten, die den Band- bzw. Linientermen der Kikuchi-Diagramme im Laue-Fall entsprechen. In diesem Fall kann der Bandterm nicht wie im Laue-Fall vom Linienterm getrennt werden. Kikuchi-Diagramme im Bragg-Fall sind nutzliche Instrumente bei der Untersuchung von Festkorperoberflachen. Ein Vergleich mit dem Experiment wird kurz diskutiert, umdie Existenz von Kikuchi-Diagrammen im Bragg-Fall nachzuweisen.

Dieletric Behaviour of Poly (Vinyl Acetate) in Solution

Abstract: Dielectric properties of dilute solutions of PVAc have been investigated for five samples (\bar M n =0.79-16.34×10 4 ) in the frequency range of 10 6 -1.5×10 8 Hz. In toluene solutions, a transition phenomenon was observed at a certain temperature between -33° and 0°C, depending on molecular weight and concentration. It was also observed in carbon tetrachloride solutions between 22° and 44°C. Above the transition temperature, T t , the relaxation time is independent of the molecular weight, while below T t , it depends on the molecular weight. The activation energy above T t has a small value of 3.5–4.2 kcal/mole which is about a half of that below. The dipole moment for a repeat unit below T t is by about 0.1 D larger than that above. It was concluded that above T t the molecule is in a random coil state, where the dipoles rotate freely, and a change in the conformation occurs at T t which restricts the dipole rotation below T t .