Showing papers by "Waseda University published in 1971"

Discussion on the mechanism of alternating copolymerization of styrene and maleic anhydride

Abstract: To clear up the detailed mechanism of the alternating copolymerization of styrene (St) and maleic anhydride (MAn) concerning the initiation species, the propagation species, the tendency of the chain transfer reaction as well as the directional tendency of the reaction between copolymer radicals and monomer complexes, the role of the charge transfer complexes, characterization of end groups and additional donor effects were examined. The equilibrium constant of the St/MAn (1 : 1) complex was determined to be 0.31 by NMR spectroscopy, that suggested considerable amounts of complexes existing in the system. As expected, a small quantity of initiator (14C-azobisisobutyronitrile (AIBN)) was incorporated into the St/MAn copolymer. Chlorine atoms were scarcely incorporated into the copolymer synthesized in CCl4 with AIBN or benzoyl peroxide (BPO) as an initiator. Hence the copolymerization was considered to be induced only by attacke of initiator radicals to the monomer or the complexes, contrary to the usual conception of telomerization. When the electron donor monomer was added to the system, the terpolymerization could be treated as a copolymerization of the two complexes, i.e., St/MAn and Donor/MAn. By adding naphthalene the rate maximum point shifted from higher concentration of MAn to the equivalent concentration of St and MAn. Degradative chain transfer to N.N-dimethylaniline was observed, confirming the existance of poly-MAn radicals. It was suggested from these results that the charge transfer complex and uncomplexed MAn took part in the copolymerization of St and MAn. This was proved kinetically. The whole mechanism was discussed. Um den Mechanismus der alternierenden Copolymerisation von Styrol (St) und Maleinsaureanhydrid (MAn) in bezug auf die Art der Initiierung und des Wachstums, die Neigung zu Kettenubertragungsreaktionen und Richtungstendenzen der Reaktion zwischen den Copolymerradikalen und den Monomerkomplexen aufzuklaren, wurden die Rolle der Elektronendonator/-akzeptor-Komplexe, die Charakterisierung der Endgruppen und Donatoreffekte untersucht. Die Gleichgewichtskonstante des St/MAn(1 : 1)-Komplexes wurde durch NMR-Spektroskopie zu 0,31 bestimmt. Das bedeutet, das betrachtliche Mengen von Komplexen in dem System existieren. Eine kleine Menge des Initiators (14C-Azoisobuttersauredinitril (AIBN)) wurde, wie erwartet, in das St/MAn-Copolymere eingebaut. Chloratome wurden so gut wie nicht in das mit AIBN oder Dibenzoylperoxid (BPO) als Initiator in CCl4 synthetisierte Copolymere eingebaut. Es wurde daher die Copolymerisation nur als durch den Angriff der Initiatorradikale auf das Monomere oder die Komplexe gestartet betrachtet, im Gegensatz zum iiblichen Konzept der Telomerisation. Wenn ein Elektronendonator-Monomeres dem System hinzugefugt wurde, konnte die Terpolymerisation als Copolymerisation der beiden Komplexe St/MAn und Donator/MAn betrachtet werden. Bei Zugabe von Naphthalin wurde die maximale Copolymerisations- geschwindigkeit von hoheren MAn-Konzentrationen zur Gleichgewichtskonzentration von St und MAn verschoben. Eine abbauende Kettenubertragung auf N.N-Dimethylanilin wurde beobachtet, wodurch die Existenz von Poly-MAn-Radikalen bewiesen wurde. Durch diese Ergebnisse wird nahegelegt, das der Elektronendonator-Komplex sowie nicht komplexgebundenes MAn an der Copolymerisation von St und MAn teilnehmen. Dieses Ergebnis wurde kinetisch gepruft, und alle Mechanismen wurden diskutiert.

Gross Theory of First Forbidden β-Decay

Abstract: The gross theory of nuclear /3-decay developed by Yamada, Takahashi and Koyama for allowed transitions is extended to include the first forbidden transitions. The effect of the giant-resonance is taken into consideration by using sum rules. The /3-strength functions of both allowed and first forbidden transitions and the /3-decay half-lives are calculated. It is shown that the theory can explain the gross properties of the first ·forbidden transitions as well as the allowed ones. In particular, the theoretical /3-strength functions of neutron­ deficient heavy nuclei are compatible with experimental data recently obtained by Hansen et al. It is also shown that the first forbidden transitions often predominate over the allowed transitions in heavy nuclei.

Optical activity of ferroelectric dicalcium strontium propionate

Abstract: Optical rotatory power of Ca2Sr(C2H5CO2)6 was accurately measured over a wide temperature range containing both paraelectric and ferroelectric states. The gyration tensor g33 has been determined from the experimental data; for instance, g33 = 2.131 × 10−5, paraelectric at 20 °C, and 2.129 × 10−5, ferroelectric at −20 °C (λ = 546 nm). A theory of optical activity based upon Born's theory has been developed in order to apply it to the ferroelectricity. In the light of the theory the ferroelectric property of Ca2Sr(C2H5CO2)6 is discussed, and it has been revealed that some change occurs around −64 °C in either antisymmetrical parts of interelectronic coupling tensor or shifts of the atoms responsible for its ferroelectricity. Nous avons mesure avec precision le pouvoir rotatoire de Ca2Sr(C2H5CO2)6 dans un large domaine de temperature comprenant a la fois les etats para et ferroelectriques, et nous avons ainsi pu determiner le tenseur de gyration g33; par exemple, g33 = 2,131 × 10−5 dans la phase paraelectrique a 20 °C, et 2,129 × 10−5 dans la phase ferroelectrique a −20 °C, pour la longuer d'onde λ = 546 nm. Nous avons developpe la theorie de Born de maniere a l'appliquer au cas de la ferroelectricite, et nous pouvons ainsi interpreter les resultats experimentaux. Nous sommes alors amenes a supposer q'un changement doit intervenir aux environs de −64 °C, soit dans la partie antisymmetrique du tenseur d'interactions entre electrons, soit dans le deplacement des atomes responsables de la ferroelectricite.

Preparation and properties of some water‐soluble cobalt (III)–poly‐4‐vinylpyridine complexes

Abstract: Water-soluble cobalt(III) chelates having a polymeric ligand such as cis-[Co(en)2-PVPCl]Cl2 and cis-[Co-(trien)PVPCl]Cl2 (PVP = poly-4-vinylpyridine) were prepared by substitution reactions between cobalt(III) chelate and PVP in water–alcohol solution. PVP of different degrees of polymerization was used as the ligand in preparation of these complexes. The PVP complexes were identified and their properties ascertained by microanalysis and by a study of the infrared, ultraviolet, visible, and PMR spectra. Most of the characteristic properties of these complexes may be ascribed to the polymeric structure of the PVP ligand.

Molekül‐ und Gitterschwingungen des orthorhombischen und ferroelektrischen Thioharnstoffs: II. Berechnung der innermolekularen und zwischenmolekularen Kraftkonstanten

Abstract: Die Frequenzen und Bewegungsformen der in den Infrarot- und Raman-Spektren des kristallinen Thioharnstoffs auftretenden Schwingungen der Elementarzellen werden unter Berucksichtigung der Schwingungszustande der Molekule und des Gitters berechnet. Die Potentialfunktionen enthalten fur die inneren Schwingungen der Molekule Kraftkonstanten eines allgemeinen Valenzkraftfeldes, fur die auseren Molekulschwingungen (Gitterschwingungen) werden lediglich Valenzkraftkonstanten in Richtung aller zwischenmolekularen Atomabstande mit Werten kleiner als 3,4 A zugrundegelegt. Die nach unseren Berechnungen ermittelten Kraftkonstanten fur die H···H-Abstande stimmen mit denjenigen uberein, die von Shimanouchi theoretisch begrundet und angewandt wurden [1, 3]. Die Schwingungsfrequenzen des Thioharnstoffs im Bereich von 700 bis 1370 cm−1 konnen keinen bestimmten inneren Koordinaten einzeln zugeordnet werden. Sie verteilen sich uber die C – N- und C – S-Valenzschwingungen sowie Deformationsschwingungen des Gerustes und der NH2-Gruppen. Auch bei den Schwingungen mit niedrigen Frequenzen (<550 cm−1) kann man klar zwischen den inneren Schwingungen und denjenigen, die zum uberwiegenden Teil von zwischenmolekularen Kraften abhangen, unterscheiden, obwohl die Lagen einiger innerer Schwingungen auch von zwischenmolekularen Kraften abhangig sind und die Frequenzen der Gitterschwingungen von inneren Kraftkonstanten der Molekule mitbestimmt werden. Die beobachteten Temperaturabhangigkeiten sowie die Faktorgruppen-Aufspaltungen werden von der Theorie qualitativ gut wiedergegeben. The infrared and Raman active vibrations of the thiourea unit cells are calculated considering the inner vibrations and the lattice forces. The potential functions for the inner vibrations contain force constants of the general valence force field; for the lattice modes, valence force constants for all intermolecular atom-atom distances less than 3,4 A are used. The calculated H···H force constants are equal to those explained theoretically and applied by Shimanouchi [1,3]. Some of the S···H (– N) force constants confirm the existence of hydrogen bonds in crystalline thiourea. The vibrations in the region 700-1370 cm−1 cannot be assigned to specific inner coordinates. They are distributed over the CS and CN stretching and bending coordinates of the skeleton and the NH2 groups. For the low frequency vibrations, inner and lattice vibrations can be distinguished clearly. Nevertheless the frequencies of some inner vibrations are dependent on intermolecular force constants. On the other hand the frequencies of lattice vibrations are determined in part by molecular force constants. The observed temperature dependence and the factor group splittings are qualitatively well reflected by the calculations.

A principal ideal theorem in the genus field

Abstract: §

Kikuchi Patterns and Inelastic Scattering

Abstract: Numerical calculations are performed for contribution of various kinds of inelastic scattering, valence electron excitations (including the plasmon excitation), core electron excitations and phonon excitations on Kikuchi pattern of Si single crystal. An explanation of defect Kikuchi band is proposed by considering inelastic scatterings in detail. Two negative circle regions on the Kikuchi band are found theoretically. Experimental results corresponding to these calculations are also presented.

Helical Twisting Power in Mixtures of Nematic and Cholesteric Liquid Crystals

Abstract: The helical twisting power in nematic ($\mathrm{methoxybenzylidene} p\ensuremath{-}\mathrm{aminophenyl}\mathrm{acetate}$)-cholesteric (cholesteryl propionate) mixtures as a function of cholesteric material concentration is studied by measuring the circular dichroism, the wavelength of selective reflection, and the Grandjean fringes. It is found that as the cholesteric material concentration increases, the twisting power of the mixtures increases linearly up to a certain concentration, beyond which, however, it increases more slowly, taking a maximum value at some specific concentration which normally falls in the high-concentration region.

X-ray dilatometric study on ferroelectric phase transition of KH2PO4 I. The order of transition

Abstract: X-ray dilatometric measurements have been made on lattice strains along the A- and B-axes of KH2PO4 as a function of temperature and biasing electric field near the Curie point. It has been clearly observed that the forced ferroelectric transitions take place in a very small but definite temperature range of 0.65 deg. A phenomenological treatment has been developed, and the coefficients of the elastic Gibbs function of KH2PO4 have been successfully determined to γ = −1.19 × 10−10 e.s.u. and Δ = 1.10 × 10−18 e.s.u., where γ stands for the coefficient of the P4 term and Δ for that the of P6 term. γ is negative. These values explain well the reported spontaneous polarization and dielectric stiffness when strong tendency to coexistence of two phases at the transition is duly allowed for. From the observations it is concluded that the ferroelectric phase transition of KH2PO4 is unequivocally of first order. Les mesurages dilatometriques par rayons-X ont ete effectues sur des deformations des A- et B-axes de KH2PO4 pres du point de Curie en fonction de temperature et champs electriques applique. Il a ete clairement observe que les transformations ferroelectriques forcees ont lieu dans une petite mais definite rangee de temperature de 0,65 deg. Un traitement phenomenologique a ete developpe et les coefficients du fonction elastique de Gibbs de KH2PO4 ont ete bien determines comme γ = −1,19 × 10−10 e.s.u., δ = 1,10 × 10−18 e.s.u., ou γ montre un coefficient du terme de P4 et δ celui du terme de P6. γ est negatif. Cettes valeurs expliquent bien la polarization spontanee et la radeur dielectrique raportees, quand la tendance forte d'une coexistence des deux phases a la transformation soit dǔment consideree. Des evidences observees, il est conclure que l'ordre de la transformation ferroelectrique de KH2PO4 est nettement premier.

Semigroups of Linear Operators in a Banach Space

Abstract: Cauchy problem in a Frechet space. Section 4 contains some results on the abstract Cauchy problem on a real half line. Section 5 deals with some relations among the results of Section 4 and the notion of distribution semigroup. Also, in that section, we discuss a characterization of the semigroup of bounded linear operators which can be extended to a distribution semigroup. Finally, Section 6 gives a characterization of class (£(£)). Also, in that section some generation theorems of well-known classes will be obtained. The author wants to express his deep gratitude to Professor I. Miyadera, Professor H. Sunouchi, Mr. N. Okazawa and Mr. T. Ushijima for their many valuable suggestions.

On the Optical Properties of all-trans Carotenoids

Abstract: Previous LCAO-ASMO-SCF-CI calculation on the π-electron system in carotenoids has been defective in the following two respects. Firstly, the relation between bond order and bond distance assumed tentatively there (being a phenomenological description of the σ-π interaction by which the bond alternation is caused) seems to be not necessarily reasonable. Secondly, a sufficient number of singly- and doubly-excited singlet-configurations have not been included in the CI calculation, so that there have remained some ambiguities in the parametrization. The purpose of the present paper is to remedy these faults of the previous calculation, to establish a firm foundation for the explanation of the optical properties of carotenoids in photoreceptor systems.

Comparison between the Conformations of Short Broken Chains and Stiff Chains

Abstract: A comparison is made of the second and the fourth moments of the end-to-end distances of several broken chain models with those of continous stiff chains. A shift factor f is introduced in such a way that n=fLD, where n is the degree of polymerization in the broken chain, L is the contour length and L/D is the mean square end-to-end distance in the limit of the long stiff chain. A single f-value is found to yield a good coincidence of both the second and the fourth moments of the end-to-end distance of the broken chain with those of the stiff chain. Values of the shift factor f which make the best coincidence of the conformations of the broken chains and the stiff chain are 1.66 for the freely rotating chain, 10.49 for the polymethylene chain and 9.18 for the chain with independent hindrance-potentials of the polymethylene type.

Effect of prolactin on the tadpole tail fin. ii. stimulatory effect of prolactin on the synthesis of acid mucopolysaccharide of the tadpole tail fin.

Abstract: Bovine prolactin stimulated the incorporation of 14C-glucose into skinless tail fin of tadpole About 88% of the 14C-radioactivity incorporated into macromolecules of the tail fin was recovered in an acid mucopolysaccharide fraction in the case of the hormone-treated animals and about 67% in the case of the control ones The acid mucopolysaccharide of the tail fin was identified as hyaluronic acid both in prolactin-treated tadpoles and control animals by Dowex-1 column chromatography and electrophoresis, confirming the result of Lipson and Silbert (1965) It is concluded from the present study that prolactin enhanced the synthesis of hyaluronic acid in tail fins 10 times as compared to untreated animals

A Computational Algorithm for Real-Time Control of System Voltage and Reactive Power Part II - Algorithm of Optimization

Abstract: An efficient computational algorithm is presented for the real-time control of system voltage and reactive power on the basis of a simplified linear model. A modified version of the complex method of Box is used for the minimization of bus voltage deviation in the first phase of optimization and a numerical search technique for the reduction of transmission losses due to reactive power flows in the second phase. The numerical example for a sample practical system is also given.

Effect of the polymeric ligand on electron-transfer reactions: Iron(II) reduction of cis-chloropoly-4-vinylpyridinebis(ethylenediamine)-cobalt(III) complexes

Abstract: Water-soluble Co(III)–PVP complexes (where PVP = poly-4-vinylpyridine) were prepared, and the specific rates and activation parameters for the iron(II) reductions of cis-Co(en)2XCl2+ (where X = PVP or pyridine and en = ethylenediamine) were determined in dilute sulfuric acid solutions. Under the conditions [H2SO4] = 0.50M, Σ[SO42−] = 1.25 M at 25°C, the second-order rate constants and activation entropies, respectively, for the cis-Co(en)2−XCl2+ are (4.10 ± 0.05) × 10−3l./mole-sec and −14 ± 0.6 eu for × = pyridine, (2.1 ± 0.1) × 10−3l./mole-sec and −6.0 ± 1 eu for × = PVP (Pn = 19), and (2.42 ± 0.08) × 10−3 l./mole-sec and −2.5 ± 0.8 eu for × = PVP (Pn = 98), where Pn is the degree of polymerization of the PVP. The main feature of the polymer effect in the electron-transfer reactions of the PVP complexes in which uncoordinated pyridine rings are present may be attributed to greater activation entropy. Such a greater entropy for the PVP complex may be partly ascribed to the intricate structure of the PVP ligand in the solution.

Proposed Applications of Holographic Techniques to the Optics of the Eye and Vision Research

Abstract: Many kinds of optical measuring instruments in ophtalmology have been developed in order to determine the optical constants of the eye. Because the object of study is the living eye, one always finds some difficulties in making measurements, and also some limitations on the accuracy of the data. For the further study of processing visual information in the living human eye, we surely need more precise information about the optical constants and the configuration of the eye including the retinal receptors.