bluuebunny/crossref_metadata_2025_split huggingface dataset:
Benzylidenation of l-Sorbose
Authors: Maeda Takashi , Kimoto (née Katsuhara) Mitsuru , Wakahara Shigeru , Tokuyama Kanji 
Published: July 2006

Abstract
The acid-catalyzed benzylidenation of l-sorbose (I) was studied. The reaction by Reichstein’s procedure gave a mixture of two diastereomeric 2,3:4,6-di-O-benzylidene-α-l-sorbofuranoses (III and IV), which were then successfully separated by preparative thin-layer chromatography. The use of slightly acidic conditions yielded l,3:4,6-di-O-benzylidene-β-l-sorbofuranose (XI), l,2:4,6-di-O-benzylidene-α- (XVII and XVIII) and-β-l-sorbofuranoses (XIX and XX), 1,2-O-benzylidene-α-l-sorbopyranoses (XXI and XXII), and 1,3-O-benzylidene-l-sorbose (XXIII). The absolute configurations at the acetal center of the five-membered benzylidene rings were assigned. A reaction sequence (I→(XXI, XXII\ightleftarrowsXXIII)→XI→IV→III) comparable with that of the ethylidenation of I was established.
Polymerization of Formaldehyde in Liquid Carbon Dioxide. I. The Cause of the Polymerizability of the Monomer
Authors: Kagiya Tsutomu , Kondo Masatsune , Narita K\={o}z\={o} , Fukui Kenichi 
Published: July 2006

Abstract
The cause of the polymerizability of formaldehyde in liquid carbon dioxide was studied in connection with the preparation conditions of the monomer. A liquid carbon dioxide solution of the monomer was prepared by two different methods, by means of the pyrolysis of α-polyoxymethylene and by means of that of the hemiformal of polyethylene glycol, under a carbon dioxide stream. By adding various sodium salts to the pyrolysis system of α-polyoxymethylene, the polymerization rate, without the addition of any catalyst, of the monomer thus obtained was found to decrease with an increase in the pKa value of the conjugated acid of the salt. The polymerization rate also decreased with the amount of sodium carbonate added. The hemiformal of polyethylene glycol was prepared by bubbling the gas evolved by the pyrolysis of paraformaldehyde into polyethylene glycol. The amount of acid present in the hemiformal thus obtained increased linearly with the pyrolysis time. The polymerization rate of the monomer obtained by the pyrolysis of the hemiformal increased in proportion to the acid content in the hemiformal. On the basis of these results, the initiation mechanism in the polymerization of formaldehyde without any additional initiator in a liquid carbon dioxide solution was discussed.
Properties of Butyl Acrylate Copolymer with Metal Ionic Crosslinkage
Authors: Hakozaki Jun-ichi , Higashimura Einosuke , Hayashibara Y\={u}ji 
Published: July 2006

Abstract
Some properties of the butyl acrylate-acrylic acid copolymer, which has ionic crosslinkage with a mono- or divalent cation, were observed. The organic solvent resistance tends to increase with an increase in the degree of neutralization with metal ions at room temperature and at 50°C. The tensile and flow properties exhibit a linear with the amounts of metal ions incorporated. The activation energies of the melt viscosity were 7.5, 10.5, and 22.0 kcal/mol for 1, 1/4, and 1/2 of metal-ion equivalents respectively. The stress relaxation behavior was observed at the temperature of 92°C; it was found that relaxation at the highest rate takes place at the initial stage of the relaxation process.
Effect of Some Cationic Detergents on Macromolecularly Stabilised Emulsions with Special Reference to Sodium Alginate and Gum Arabic as Emulsifiers
Authors: Prakash Chandra , Srivastava S N 
Published: July 2006

Abstract
The effect of some cationic detergents viz. cetyl pyridinium bromide, lauryl pyridinium chloride and phenyl trimethyl ammonium chloride has been studied on stabilised by sodium alginate and gum arabic emulsions. Zeta potentials were measured at different concentrations of cationic detergents microelectrophoretically. The particle size was determined microphotographically. With the help of zeta potential and particle size the interaction energies were calculated by summing up attraction and repulsion energies in the light of D.V.O. theory. For attraction energy the van der Waals constant was computed theoretically from the optical data and was obtained to be 6.7×10−14 erg. The interaction energies thus obtained gave very high energy barriers which completely obviated the occurrence of flocculation in primary minima, causing flocculation to occur in secondary minima. The theoretical degrees of aggregation were calculated and plotted at different values of A. The flocculation occurring in the system was observed haemocytometrically by counting the number of singlets and doublets and the degrees of aggregation were calculated. With the help of observed degrees of aggregation the operating value of van der Waals constant has been estimated by interpolating them into the theoretical curves, which is an indirect approach to ascertain the value of van der Waals constant. The values of A obtained are 3.0×10−13 and 2.6×10−13 erg for sodium alginate and gum arabic systems respectively. The binding parameters, number of binding sites available and free energy of adsorption have also been calculated.
Role of Doped Lithium in Nickel Monoxide in the Formation of Higher Valency Nickel Oxides by Anodic Oxidation
Authors: Yoneyama Hiroshi , Tamura Hideo 
Published: July 2006

Abstract
The anodic oxidation and cathodic reduction behavior of a sintered body of lithiated nickel oxide were studied. The electrode with the higher Li content was more active than that with the lower Li content with regard to the electrochemical oxidation and reduction in the potential range between oxygen and hydrogen evolution. The quantity of the higher-valency nickel oxide having an apparent valence state of nickel ions from +8/3 to +4 formed by the anodic oxidation was estimated by measuring the quantity of electricity required for reducing it to −0.14V vs. SCE. This quantity is proportional to the Li content for electrodes containing more than 0.04 atom% of Li.
Evaluation of the Activation Energies of Radical Substitution Reactions in the Gaseous Phase. I. An Empirical Method Employing the Morse Function
Authors: Kagiya Tsutomu , Sumida Yūzō , Inoue Tokuji , Dyachkovskii Fridrich S 
Published: July 2006

Abstract
An empirical evaluation of the activation energy has been carried out for the radical substitution reaction involving polyatomic molecules. The potential energy along the reaction path is assumed to be expressed for the initial and the final systems by the two Morse functions with the coefficient “a′,” which is different from the “a” in the usual Morse function of the bond. The difference between the a′Δr* values in the Morse functions of the initial and the final systems in the transition state is empirically determined as a function, af′Δrf*–ai′Δri*=βQ, of the reaction heat, Q. From the Morse function with “a′” and the above relation, the activation energy is calculated by using the bond dissociation energies of the initial and the final molecules. The treatment proposed is useful for the evaluation of the activation energies of many types of radical substitution reactions.
The Photochemical Rearrangement of Phenyl Acetate
Authors: Shizuka Haruo , Morita Toshifumi , Mori Yuji , Tanaka Ikuzo 
Published: July 2006

Abstract
The photochemical rearrangements of phenyl acetate and p-substituted phenyl acetates have been studied. The quantum yields of the rearrangements of phenyl acetate in cyclohexane were independent of the irradiation time, the concentration of phenyl acetate (&lt;2×10−2 mol/l), the temperature (20–70°C), and the presence of piperylene (a triplet quencher) or oxygen. The quantum yields for the formations of o- and p-hydroxyl acetophenones and of phenol were 0.17, 0.15, and 0.06 respectively in cyclohexane. Comparing the quantum yields for phenyl acetate rearrangements with those for p-methylphenyl acetate, the quantum yields for the predissociation of the O–CO bond and the back reaction, and the recombination ratio were estimated to be 0.61, 0.23, and 0.9 respectively in cyclohexane. The relative rate constants of the back reaction and the o- and p-rearrangements were parallel to the odd π electron densities of the phenoxy radical. These results have shown that the reaction scheme of phenyl acetate in the liquid phase at 2537 Å is similar to that of acetanilide.
Electron Spin Resonance Studies of the Formation of Anion Radicals on γ-Irradiated Silica Gel
Authors: Yamada Yoshio , Hasegawa Akinori , Miura Masaji 
Published: July 2006

Abstract
The ESR spectra assigned to the anion radicals of SO2−, (TCNE)− (tetracyanoethylene), and O2− were obtained for, respectively, sulfur dioxide, TCNE, and oxygen when these gases were adsorbed on γ-irradiated silica gel. As regards sulfur dioxide, a characteristic change in the concentration of the SO2− radical was observed during the post-irradiation with high-energy UV light. In the case of carbon dioxide, the CO2− radical was produced only when UV post-irradiation was added to γ-irradiation. The assignments were principally made in comparison with the reported g-values. Especially, the identification of the CO2− radical was ascertained by using 13C. The analyses of the g-factor for the O2− radical and of 13C hyperfine constants for the CO2− radical gave information on the interaction of the radicals on a solid surface with the cations in the adsorption center. In view of the fact that each of these molecules possesses a different degree of electron affinity, the results described above indicate that the electrons trapped in the defects of the silica gel surface transfer to the adsorbed molecules and that UV light promotes the electron transfer.
Kinetics of the Transition of Titanium Dioxide Prepared by Sulfate Process and Chloride Process
Authors: Suzuki Akira , Tukuda Ritushi 
Published: July 2006

Abstract
The kinetics of the phase transformation of anatase to rutile was studied by means of X-ray diffraction. Samples of anatase were prepared by sulfate and chloride processes. The kinetic data could well be expressed by the equation
α=1−e−btn,
where α is the fraction of anatase transformed in time t, and b and n constants. The activation energy of the phase transformation is 105 kcal/mol for the sample prepared by the sulfate process, and 107 kcal/mol for the sample prepared by the chloride process. These values of activation energy are compared with those previously obtained.
Mixed Conduction in Stabilized Zirconia at a Low Oxygen Partial Pressure
Authors: Hirota Kazushi 
Published: July 2006

Abstract
The electromotive force of the oxygen concentration cell, O2 gas/stabilized zirconia/Fe(+C)-melt+COgas, was measured at 1900°K as a function of the carbon concentration in iron melt, and the transference number of the stabilized zirconia was calculated. The transference number of the ions in the stabilized zirconia partition is less than unity over the whole range of carbon concentration. When the results are compared with the equations derived from plausible models, a reasonable coincidence is obtained.
Anionic Telomerizations of Styrene with Butylamines
Authors: Asahara Teruzo , Sen\={o} Manabu , Tanaka Sadayoshi , Den Norio 
Published: July 2006

Abstract
The anionic telomerizations of styrene with n-butylamine, s-butylamine, t-butylamine and isobutylamine catalyzed by sodium metal were investigated. The structures of the products were discussed by the NMR spectra obtained in carbon tetrachloride and identified to be N-butyl-2-phenylethylamines and N-butyldi(2-phenylethyl)amines. The general reaction scheme was proposed and interpreted with the concept of the anionic telomerization, where amine acts as a telogen and styrene as a taxogen.
Infrared Study of the Conformational Equilibria of meso- and racemic-2,3-Dichlorobutanes
Authors: Iimura Kazuyoshi , Kawakami Naoto , Takeda Masatami 
Published: July 2006

Abstract
The conformational equilibria of rotational isomers of meso- and racemic-2,3-dichlorobutanes were investigated in various solvents by an infrared method. The coexistence of three rotational isomers was found for each of the meso and racemic-2,3-dichlorobutanes. However, the equilibrium concentrations changed depending on the solvent dielectric constant. The equilibrium concentration of the less polar form of a rotational isomer, in which the conformation is extended trans with respect to the Cl–C–C–Cl linkage, decreased as the solvent dielectric constant increased. The energy differences between the rotational isomers in the gaseous state and in acetonitrile solvent were also discussed.
ESR Studies of Carboxylic Acid- and Ester-Radical Anions Produced by γ-Irradiation at 77°K
Authors: Nakajima Yukihiko , Sato Shin , Shida Shoji 
Published: July 2006

Abstract
A series of monocarboxylic acids and esters have been γ-irradiated at 77°K, either pure or in the rigid matrix of 2-methyltetrahydrofuran, and the products have been examined by ESR spectroscopy. The spectra obtained in the pure state showed that the primary paramagnetic species in each case is the corresponding radical anion, (Remark: Graphics omitted.). In the rigid matrix, these characteristic spectra have been obtained after illuminating the γ-irradiated sample with visible light at the expense of the spectra of trapped electrons. When ultraviolet light was used for the illumination, the spectra of the radical anions disappeared, but instead appeared the spectra of the radicals produced by the decomposition of the radical anions. The latter spectra were almost the same as those obtained by the direct photolyses of acids and esters.
Studies of the Estimation of the Interfacial Energy of Embryo in Solid-Liquid Systems
Authors: Nakai Tasuku 
Published: July 2006

Abstract
A novel method for the estimation of the interfacial energy of an embryo from the solubility data in solid-liquid systems has been proposed. The distribution function of embryos in solutions derived thermodynamically has been used as the base for the present treatment. The interfacial energies were calculated numerically for three different combinations of solute and solvent, namely, water-inorganic salt, water-organic compound, and organic solvent-organic compound. A fairly good linear relationship was observed between the interfacial energies calculated and the temperatures over the whole temperature range of solubility data. The semiempirical equation describing the relationship between the interfacial energy of the embryo and the temperature in the solid-liquid system was found to be exactly the same as that between the surface energy of the liquid in contact with gas through a free surface and the temperature. The size dependence of the interfacial energy has also been briefly described.
Temperature-jump Studies of the Kinetics of the Formation of the Monochloro and Monobromo Complexes of Iron(III)
Authors: Yasunaga Tatsuya , Harada Shoji 
Published: July 2006

Abstract
The temperature-jump method was used to study the kinetics of FeCl2+ and FeBr2+ complex formations in aqueous solutions. Complex formation is composed of two paths. In the acid-independent path, the rate-determining step of complex formation may be the reaction between Fe(H2O)53+ and X− (X−=Cl−, Br−). The other path is that via the hydrolysis of ferric ions, and the rate-determining step is the loss of a water molecule from the inner coordination sphere of the metal ion. The kinetic values obtained are in good agreement with the results obtained by the flow method.
Mössbauer Spectral Observation of α-Fe2O3 Supported on Silica Gel during Activation
Authors: Tachibana Taro , Ohya Toshie , Yoshioka Tohru , Koezuka Junji , Ikoma Hiroko 
Published: July 2006

Abstract
Mössbauer spectral studies were made of samples of α-Fe2O3 highly dispersed on silica gel before and after activation, which consisted of evacuated heating at 475°C. The spectra gave Ividence that Fe2+ ions were produced from α-Fe2O3 during the activation process. Reduction was impossible after the activation and oxidation had been repeated three times. However, the inactivated sample came to be again reduced by activation after having been exposed to water vapor at room temperature. In order to explain these facts, a working hypothesis was advanced that the hydroxyl groups near the surface of the particles play a principal role in reacting with organic contamination from the vacuum system, as a result bringing about the partial reduction of α-Fe2O3.
Thermodynamic and X-Ray Studies of Solid Solutions of Silver Bromide and Sodium Bromide
Authors: Tsuji Toshihide , Fueki Kazuo , Mukaibo Takashi 
Published: July 2006

Abstract
Activity, and partial molal free energy, enthalpy and entropy of AgBr in AgBr-NaBr solid solutions have been obtained at 350 and 400°C from the e.m.f. data of galvanic cells of the type Ag/AgBr-NaBr/Br2. It has been found that the solid solution forms a regular solution defined by Hildebrand. A miscibility gap has been found by the study of galvanic cells and confirmed by high temperature X-ray diffraction. A new phase diagram of the AgBr-NaBr system is presented.
Anharmonic Potential Constants and Vibrational and Rotational Parameters for Hydrogen Cyanide
Authors: Nakagawa Toru , Morino Yonezo 
Published: July 2006

Abstract
The general fourth-order potential constants, f, for hydrogen cyanide were determined by a least-squares analysis applied to the observed values of the vibrational energies and the rotational constants for six isotopic species, H12C14N, H13C14N, H12C15N, D12C14N, D13C14N, and D12C15N. The normal frequencies, ωi, the cubic and quartic potential constants, kijk and kijkl, the anharmonicity constants, xij, the vibration-rotation interaction constants, αi, and the Coriolis coupling constants, ζijx were calculated for the six isotopic species.
Polarographic Study of the Cadmium(II)-Ethylenediaminetetrapropionate Chelate
Authors: Kodama Mutsuo , Tominaga Yayoe 
Published: July 2006

Abstract
The d.c. polarographic behavior of the cadmium(II) ion in ethylenediaminetetrapropionate (EDTP) was studied in the pH range from 8.30 to 10.30. Over the entire range of experimental conditions employed, the cadmium(II)ion invariably gave a single well-defined wave corresponding to the following reversible two-electron reduction:
(Remark: Graphics omitted.)
Even in the presence of ammonia or the alaninate ion, the cadmium(II) ion in the EDTP solution also behaves reversibly in a polarographic electrolysis. However, the half-wave potential was found to be shifted to the more negative potentials by the addition of ammonia or alaninate. This was ascribed to the formation of a mixed ligand chelate involving ammonia or the alaninate ion. From the relation between the shift of the half-wave potential and the concentration of ammonia or alaninate, the composition and the stability constant of the mixed ligand chelate were determined and the electrode reaction was established as:
(Remark: Graphics omitted.)
where A means the ammonia or the alaninate ion. The K2, KNH3, and Kala values determined were 5.5×102, 1.38×102, and 2.61×104 respectively.
The Spectrophotometric Determination of Zirconium(IV) with Bromopyrogallol Red
Authors: Sakai Takayoshi , Funaki Yûko 
Published: July 2006

Abstract
Zirconium(IV) reacts with an excess of bromopyrogallol red to form a violet complex. The constant absorbance of a solution containing the complex is obtained in the pH range from 5.0 to 5.4 at 670 mμ. About 25 min is required to complete the chelate formation in a boiling water bath. The complex thus formed is stable for at least 3 hr. The color system obeys Beer’s law in the range from 4 to 35 μg zirconium in 25 ml. The sensitivity of the reaction is 0.002 μg per cm2 for an absorbance of 0.001. In composition the complex has a metal-to-ligand ratio of 1:2. The molar absorptivity and the apparent formation constant of the complex are calculated to be 7.01×104 at 670 mμ and 1.11×109 at pH 5.2 respectively. The effect of diverse ions on the determination is examined.
Preparation and Properties of Di-μ-alkoxo-bis(3-alkyl-5-methylsalicylaldehydato)dicopper(II)
Authors: Inazu Takako , Okawa Hisashi , Inazu Takahiko , Yoshino Tamotsu 
Published: July 2006

Abstract
In this paper, the syntheses of copper(II) complexes of 3-alkylsalicylaldehydes, B, as well as the syntheses and properties of dimeric copper(II) complexes, C, with bridged alkoxy groups are reported.
Cooxidation of Hydrocarbons in Liquid Phase. VI. Reactivities of Hydrocarbons and Peroxy Radicals
Authors: Niki Etsuo , Kamiya Yoshio , Ohta Nobuto 
Published: July 2006

Abstract
Cooxidation of all the combinations of two hydrocarbons among styrene, α-methylstyrene, tetralin and cumene was studied at 70° C in the presence of azobisisobutyronitrile as a thermal initiator. The reactivity ratios for each binary mixture were determined by several appropriate methods. The relative reactivities of styrene, α-methylstyrene, tetralin and cumene toward the peroxy radicals were approximately in the ratio 15 : 10 : 5 : 1. It was also concluded that the secondary peroxy radicals were more reactive than the tertiary peroxy radicals and that the polymeric peroxy radicals were more reactive than the normal alkylperoxy radicals.
Synthetic Studies of the Flavone Derivatives. XII. The Synthesis of 8,3′-Dimethoxy-5,7,4′-trihydroxyflavone
Authors: Fukui Kenji , Nakayama Mitsuru , Horie Tokunaru 
Published: July 2006

Abstract
The partial benzylation of 3-methoxy-2,4,6-trihydroxyacetophenone gave a mixture of 2,4-dibenzyloxy-6-hydroxy- and 4,6-dibenzyloxy-2-hydroxy-3-methoxyacetophenone. The latter was esterified with 4-benzyloxy-3-methoxybenzoyl chloride, and the resulting ester was converted into 8,3′-dimethoxy-5,7,4′-tribenzyloxyflavone via the corresponding diketone. The catalytic debenzylation of the flavone gave 8,3′-dimethoxy-5,7,4′-trihydroxyflavone. Its diethyl ether was also prepared from 3,6-dimethoxy-4-ethoxy-2-hydroxyacetophenone by an unambiguous method.
The Synthesis of 3-Hydroxy-8,9-dimethoxypterocarpan
Authors: Fukui Kenji , Nakayama Mitsuru , Harano Teruo 
Published: July 2006

Abstract
7,2′-Dihydroxy-4′,5′-dimethoxyisoflavone was obtained from 7-hydroxy-2′,4′,5′-trimethoxyisoflavone by selective demethylation with aluminum chloride in acetonitrile. By partial benzylation, the dihydroxyisoflavone then gave 7-benzyloxy-4′,5′-dimethoxy-2′-hydroxyisoflavone. The subsequent treatment of the latter with sodium borohydride afforded 3-hydroxy-8,9-dimethoxypterocarpan via its 3-benzyloxy-compound.
Kinetic Studies of the Triethylenediamine-catalyzed Transamidation of 1,3-Diphenylurea with n-Butylamine in Dioxane
Authors: Furuya Yoshiaki , Itoho Kazuo , Miyagi Harue 
Published: July 2006

Abstract
The rates of the transamidation of 1,3-diphenylurea (abbreviated as DPU) with n-butylamine (BA) in dioxane in the presence of triethylenediamine (TED), forming n-butylphenylurea (BPU), aniline and carbon dioxide, were followed ultraviolet-spectrophotometrically. The rate of the reaction satisfied the following equation:
υ={k1′+k2′[TED]}[DPU]+{k2″+k3[TED]}[BA][DPU].
The first and second terms correspond to the non- and the TED-catalyzed hydrolysis of diphenylurea, while the third and fourth terms represent, respectively, the non- and the TED-catalyzed transamidation. In both the non- and the TED-catalyzed transamidation, a probable mechanism which involves the nucleophilic attack of the lone pair of the N-atom on the carbonyl C-atom of diphenylurea, followed by the formation of ion pairs of quaternary ammonium salt and of quaternary ammonium type salt, was discussed.
Aminosugars. XVII. Synthesis of Benzyl 2-Acetamino-2-deoxy-α-d-glucopyranosiduronic Acidamides and N-(2-Acetamino-2-deoxy-d-glucuronyl)-aminoacids
Authors: Yoshimura Juji , Sato Tadahide , Ando Hiroaki 
Published: July 2006

Abstract
Benzyl 2-acetamino-2-deoxy-α-d-glucopyranosiduronic acid was obtained by direct oxidation of the corresponding glucoside, and converted to esters (methyl, ethyl and benzyl) and amides (methyl, ethyl, phenyl and benzyl). Condensation of the uronic acid with aminoacid benzyl-esters (gly, l-ala, l-asp, and l-glu) by dicyclohexylcarbodiimide gave the corresponding amides, some of which were hydrogenated to N-(2-acetamino-2-deoxy-d-glucuronyl)-aminoacids. Acid hydrolysis of the peptides were examined.