bluuebunny/crossref_metadata_2025_split huggingface dataset:
The pNa Study of Sodium Alkyl Sulfates in Aqueous Solutions
Authors: Satake Iwao , Tahara Takashi , Matuura Ryohei 
Published: July 2006

Abstract
The counter-ion activity coefficient of sodium alkyl sulfate with chain length from C8 to C14 was determined in aqueous solutions and in the presence of added magnesium ion. The degree of association of sodium ion to the micelle (β) can be deduced from the concentration dependence of the counter-ion activity. The value of β so determined in the presence of magnesium ion was confirmed to decrease rapidly as the relative concentration of magnesium ion increases. The observed change of counter-ion activity with concentration was found to be interpreted in terms of a lameller micelle model.
A New Monoclinic Phase of Cerium Orthovanadate (CeVO4)
Authors: Yoshimura Masahiro , Sata Toshiyuki 
Published: July 2006

Abstract
A new monoclinic phase of cerium orthovanadate, CeVO4(H), was found during the course of oxidation of pseudo-perovskite CeVO3 below 400°C. It has been confirmed to crystallize in the huttonite-type structure (C2h5−P21⁄n), that of LaVO4. The lattice parameters were determined to be:
a 0=6.98Å, b0=7.22Å, c0=6.76Å, β=105°02′, V=328Å3 and Z=4.
This phase was metastable, and exothermally transformed into a known stable CeVO4 (tetragonal zircon-type, D4h19−I41⁄amd) above 400°C, releasing a small amount of oxygen. From magnetic, chemical and thermogravimetric analyses, the valences of cerium ion and vanadium ion in CeVO4-(H) seem to be tripositive and pentapositive respectively, but V4+ ion is mixed in zircon-type CeVO4; CeVO4(Z).
Solvent Effects in the Oxidation of Hydrocarbons. I. Chain Initiation by Azobisisobutyronitrile
Authors: Niki Etsuo , Kamiya Yoshio , Ohta Nobuto 
Published: July 2006

Abstract
The effects of solvents on the rate of decomposition and the efficiency of radical production by AIBN were studied by measuring the rate of evolution of nitrogen from AIBN and the inhibition time in the oxidation of tetralin. The rates of decomposition of AIBN were larger in aromatic solvents than in aliphatic solvents. The efficiency of AIBN was found to depend more on the viscosity of the medium than on the polarity of the solvents. The requirements for the determination of the inhibition time are discussed.
Solvent Effects in the Oxidation of Hydrocarbons. II. Oxidations of Tetralin in Various Solvents
Authors: Niki Etsuo , Kamiya Yoshio , Ohta Nobuto 
Published: July 2006

Abstract
The rates of oxidation of 1.47m tetralin in a variety of solvents at 70°C in the presence of 1.00×10−2m AIBN varied by a factor of 2.9, ranging from 6.39×10−6 mol/l/sec in n-decane to 1.84×10−5 mol/l/sec in nitromethane. The rate of oxidation was dependent on the composition of the solution as well as the kinds of solvents. It was found that the solvents affected the initiation step approximately as much as they affected the propagation and/or temination step. The rate of initiation by AIBN was mainly dependent on the viscosity of the medium, while that of propagation and termination was mainly determined by the dielectric constant of the medium. The correlation between log(kp⁄(2kt)1⁄2) and (D–1)/(2D+1) was discussed, where kp and kt are the rate constants for propagation and termination steps, respectively, and D is the dielectric constant of the medium, under conditions where the complication caused by the selective solvation could be excluded.
Stereochemical Studies of Monoterpene Compounds. VII. Conformational Study of 4-Hydroxymenthones by Temperature-dependent Circular Dichroism
Authors: Shishibori Tsuyoshi , Suga Takayuki , Watanabe Satoru , Matsuura Tamon 
Published: July 2006

Abstract
The conformational analysis of a stereoisomeric pair of 4-hydroxymenthones, (1R:4R)-(−)-4-hydroxymenthone (1) and (1R:4S)-(+)-4-hydroxyisomenthone (2), was made by means of temperature-dependent circular dichroism. It was demonstrated that α-hydroxyketone (1) exists in the conformational equilibrium: 1a\leftrightarrows1b; the conformer 1a exists predominantly in a nonpolar medium, whereas the conformer 1b is more stable than 1a in a polar medium. On the other hand, the other isomer, (2), exists preferentially in the state of the conformer 2b in either a polar or a nonpolar solvent. The results were interpreted in terms of the competition of the steric factor and intramolecular hydrogen-bonding.
α-Diketone Rearrangement. The Reaction of 1,2-Cyclohexanedione with Arginine and with Guanidine
Authors: Anzai Kentaro 
Published: July 2006

Abstract
A novel rearrangement reaction of cyclohexanedione, involving the loss of hydrogen in the product, is described. Cyclohexanedione and guanidine react in an alkaline solution to produce 2-amino-4-oxo-1,3-diazaspiro[4.4]non-1-ene (VIII) and l-hydroxy-3-amino-5-oxo-2,4-diazabicyclo-[4.3.0]non-2-ene (IX), the latter being an oxidized product. Similarly, cyclohexanedione reacts with arginine, producing, among other products, N5-(1-hydroxy-5-oxo-2,4-diazabicyclo[4.3.0]non-2-ylidene)-ornithine (III).
An MO-theoretical Interpretation of the Nature of Chemical Reactions. II. The Governing Principles
Authors: Fukui Kenichi , Fujimoto Hiroshi 
Published: July 2006

Abstract
The importance of the overlapping between the highest occupied (HO) molecular orbital (MO) of an electron donor and the lowest unoccupied (LU) MO of an electron acceptor in determining the favorable position and spatial direction of a chemical reaction is emphasized by setting up the following auxiliary principles: the principle of a positional parallelism between the chargetransfer and the bond-interchange, the principle of a narrowing of the inter-frontier energy-level separation, and the principle of a growing frontier density along the reaction path. These subprinciples work in a cooperative manner to enable us to arrive at this general governing principle: most of the chemical interactions are liable to occur at the position and in the direction where the overlapping of the HO and the LU of the respective reactants is at its maximum; in an electron-donating reactant, HO predominates in the overlapping interaction with the MO’s of the other reactant, whereas LU does so in an electron-accepting reactant; in the reactants which possess singly-occupied (SO) MO’s, these play the part of HO or of LU, or of both. These particular MO’s, HO, LU, and SO are “generalized frontier orbitals” in chemical reactions. This principle is applied to uni-centric reactions to give the orientation rule; if it is applied to multi-centric reactions, the stereoselection rule is obtained.
On the Emission of Excited Complexes Formed between Condensed Aromatic Hydrocarbons and Aliphatic Amines
Authors: Nakajima Akira 
Published: July 2006

Abstract
Anomalous emission observed at long wavelengths in the systems of condensed aromatic hydrocarbons and aliphatic tertiary amines has been studied. The anthracene-tri-n-butylamine system has been dealt with in detail. On the basis of the absorption spectrum, the temperature dependence of the long-wavelength emission and the relation between the quenching of the hydrocarbon fluorescence and the intensity of the long-wavelength emission, it has been concluded that this emission originates from the excited complex formed between an excited hydrocarbon and an amine. The interaction involved in excited-complex formation is of a charge-transfer type. This was confirmed by the correlation of the wavelengths of the excited-complex emission with the ionization potentials of amines and the electron affinities of aromatic hydrocarbons and by the large dipole moment of the excited complex.
Thermodynamic Properties of Carbon Tetrafluoride from 4°K to Its Melting Point
Authors: Enokido Hisae , Shinoda Takako , Mashiko Yo-ichiro 
Published: July 2006

Abstract
Thermodynamic properties of solid and liquid carbon tetrafluoride were measured at temperatures from 4°K to 100°K. The heat of transition was found to be 349.5±0.9 cal/mol, the transition temperature 76.221°K, the heat of fusion 168.6±0.05 cal/mol, the triple point temperature 89.515°K and the triple point pressure 0.80±0.03 Torr. The amount of impurity in the specimen of CF4 was estimated to be 0.0147 mol% from the measurement of the melting point range. The values of molal entropy of CF4 as an ideal gas at 298.2°K, were calculated from the calorimetric and spectroscopic data as 62.63 e.u. and 62.45 e.u., respectively. The Debye characteristic temperature at 0°K was derived from the low temperature heat capacity data, and the θD(T) curve was compared with that for neopentane taking into account the octupole interaction of molecules in the crystal.
Reactions of Metal Chelates. IV. The Reactions of Bis(salicylaldehydato)-copper(II) with Diethylenetriamine and Triethylenetetramine
Authors: Nakao Yasuo , Nakahara Akitsugu 
Published: July 2006

Abstract
The reactions of bis(salicylaldehydato)copper(II) with diethylenetriamine and triethylenetetramine were investigated under several different conditions. In water, in the absence of other reagents, the reactions gave uncharged bis (salicylaldehyde)-diethylenetriamine- and -triethylenetetramine-copper(II), respectively. In the presence of an acid the resulting complexes were the respective cation complexes, in which only one of the two terminal nitrogen atoms was in the form of Schiff base with salicylaldehyde. In the presence of a salt, the resulting complex from diethylenetriamine was a cation complex, and that from triethylenetetramine an uncharged complex. Three new copper(II) chelates were obtained.
Hydrodynamic Voltammetry with the Convection Electrode. III. The Measurements of the Kinetic Parameters of the Electrode Reaction. Part I
Authors: Suzuki Junsuke 
Published: July 2006

Abstract
We have proposed the determination of the kinetic parameters of the electrode reaction by means of convective voltammetry. At the pushed-out mercury-drop convection electrode (PM-DCE), the ratio of the current on a totally-irreversible wave to the limiting current was derived as follows:
(Remark: Graphics omitted.)
This equation was applied to the determination of the kinetic parameters for the electro-reduction of cupric ions in a 0.1 m perchloric acid solution containing 0.05% Triton X-100. It was found that the values of αn and k° the kinetic parameters are 0.59 and 4.2×10−9 cm/sec respectively.
Studies of Phosphorylation. III. Selective Phosphorylation of Unprotected Nucleosides
Authors: Yoshikawa Masaharu , Kato Tetsuya , Takenishi Tadao 
Published: July 2006

Abstract
During an investigation of the factors affecting the reaction of 2′,3′-O-isopropylidene nucleosides with phosphoryl chloride, trialkyl phosphates were found to be powerful accelerators and useful solvents for the phosphorylation. The addition of a trialkyl phosphate to a large excess of phosphoryl chloride was markedly effective in promoting the phosphorylation; further, the lower alkyl phosphates, such as trimethyl and triethyl phosphates, were able to replace the excessive amount of phosphoryl chloride as solvents. When unprotected nucleosides were treated with phosphoryl chloride in trimethyl phosphate, the corresponding 5′-phosphates were mainly produced, together with a small amount of highly-phosphorylated products, in good yields. On the contrary, the treatment of 5′-O-acetyl nucleosides in a similar manner gave the corresponding 2′(or 3′)-nucleotides in low yields. The formation of the 2′(or 3′)-phosphate was strongly inhibited by the addition of a small amount of water to the reaction mixture. Thus, the selective phosphorylation of unprotected nucleosides to the 5′-nucleotides in a one-step procedure was accomplished.
Photochromic Color Change of the Dimer of Triphenylimidazolyl at Low Temperatures
Authors: Maeda Koko , Hayashi Taro 
Published: July 2006

Abstract
The photochromic dimer of triphenylimidazolyl which is one of two dimers obtained by oxidation of triphenylimidazole shows photochromism at temperatures between room temperature and −196°C in solutions and in a solid state. At temperatures higher than about −20°C the photochromic color in solutions is reddish-purple, at temperatures lower than about −150°C the color is bluish-purple and at intermediate low temperatures the photochromic color does not appear. Absorption spectrum and ESR measured with the change of temperature showed variations corresponding to the change of color. The photochromic color in a solid state was light reddish-purple above about −70°C and bluish-purple at −196°C. The mechanism of the color change was discussed in connection with that of the photochromism at room temperature and the results obtained from spectroscopic and ESR studies.
Mechanism of the Solvent Effect in a Binary Solvent System on the Cationic Polymerization of N-Phenylethylenimine
Authors: Kagiya Tsutomu , Kondo Tomizo 
Published: July 2006

Abstract
The effect of the binary solvent systems on the polymerization of N-phenylethylenimine with a formic acid catalyst was studied quantitatively. In an acetonitrile-acetone system composed of components with similar nucleophilicities but with very different dielectric constants, the polymerization rate increases with an increase in the dielectric constant of the binary solvent system. In an acetonitrile - N,N-dimethylacetamide system composed of components with very different nucleophilicities but with similar dielectric constants, on the other hand, the rate was markedly depressed by the addition of a small amount of N,N-dimethylacetamide with a large nucleophilicity. On the basis of these results, a mechanism of the solvent effect in a binary solvent system was proposed; the rate equation of the polymerization was expressed empirically as a function of both the dielectric constant of the binary solvent mixture and the nucleophilic equilibrium constant, and the concentration of the component.
Synthesis of Pyrrole Nucleosides by the Photo-dehydrogenation of Δ3-Pyrroline Derivatives
Authors: Kawana Masajiro , Emoto Sakae 
Published: July 2006

Abstract
1-(β-d-Glucopyranosyl)pyrrole (VI) was prepared by the photo-dehydrogenation of 1-(2′,3′,4′,6′-tetra-O-acetyl-β-d-glucopyranosyl)-Δ3-pyrroline (IV) in the presence of oxygen and benzophenone, followed by deacetylation. The nucleoside (VI) was also derived directly from 1-(d-glucosyl)-Δ3-pyrroline (III) by photochemical means. The synthesis of 1-(α-d-ribofuranosyl)-pyrrole (XI), its β-anomer (XII), and 1-(β-d-ribopyranosyl)pyrrole (XIII) was accomplished by photodehydrogenation of 1-(2′,3′-O-isopropylidene-d-ribosyl)-Δ3-pyrroline, followed by the removal of the protecting group. The treatment of 1-(2′,3′-O-isopropylidene-α-d-ribofuranosyl)pyrrole (VIII) with 80% aqueous acetic acid afforded a novel α-cyclonucleoside, 1-(2-C,2′-O-isopropylidene-α-d-ribofuranosyl)pyrrole (XIV), besides XI–XIII. The formation of pyrrole by the photodehydrogenation of Δ3-pyrroline (II) itself was confirmed by gas chromatography.
Resolution of Amino Acids. IX. Studies on the Preparation of β-Hydroxyasparagines and Configuration of Natural Hydroxyasparagine
Authors: Okai Hideo , Izumiya Nobuo 
Published: July 2006

Abstract
Crystalline threo-and erythro-β-hydroxy-l-asparagine were prepared via asymmetric hydrolysis of the corresponding hydroxy-l-aspartic acid diamide by leucine aminopeptidase. The isomers of hydroxy-l-asparagine obtained were compared with the natural hydroxyasparagine isolated from human urine with respect to optical rotation and chromatography. From the results it is concluded that the spacial configuration of the natural product is that of erythro-β-hydroxy-l-asparagine. Additional studies were also carried out to prepare threo- and erythro-β-hydroxy-Dl-asparagine from the corresponding hydroxy-Dl-aspartic acid diamide without the enzyme.
Mechanism of Intramolecular Energy Transfer in Rare Earth Chelates as Revealed by Infrared Absorption Measurements
Authors: Matsuda Yoshihisa , Makishima Shoji , Shionoya Shigeo 
Published: July 2006

Abstract
The purpose of this paper is to clarify the mechanism of intramolecular energy transfer from the triplet state of the ligand to the excited levels of the central ion in rare earth chelates. As to seven kinds of samarium β-diketonates, the frequency of infrared absorption due to the stretching vibration of the chelate bond, \ ildeνMO, and the manner of energy transfer are investigated. The probability of energy transfer is estimated from the ratio of the intensity of the samarium emission to that of the ligand phosphorescence, ISm⁄IPh. The overlap integral, S, between the ligand phosphorescence spectrum and the samarium absorption spectrum is obtained. It was found that a linear relation roughly holds between log{(ISm⁄IPh)⁄S} and \ ildeνMO. On the basis of this fact, one is led, by making some arguments, to the conclusion that intramolecular energy transfer is dominated by the resonance mechanism due to the exchange interaction of the π electron system of the ligand triplet state with the f electron system of the central rare earth ion.
Association Involving Optically Active Ions. II. Association Constants of Tris(ethylenediamine)cobalt(III) and Tris(propylenediamine)-cobalt(III) Ions with Some Anions
Authors: Ogino Kazuko 
Published: July 2006

Abstract
Association constants of [Co en3]3+ (en=ethylenediamine) and d- and l-[Co d-pn3]3+ (pn=propylenediamine; d- and l- refer to the sign of optical rotation at sodium D-line) with some anions have been determined spectrophotometrically. Values are as follows: [Co en3]3+·SO42−49, [Co-en3]3+·glycollate− ∼5, d-[Co d-pn3]3+·SO42− 70, d-[Co d-pn3]3+·d-tart2− (tart2−=bivalent tartrate anion) 30, d-[Co d-pn3]3+·l-tart2− 28, l-[Co d-pn3]3+·SO42− 43, l-[Co d-pn3]3+·d-tart2− ∼7, l-[Co-d-pn3]3+·l-tart2− ∼16. These association constants are discussed in terms of the microscopic interaction between the ions. The effect of outer-sphere association on the circular dichroism and optical rotatory dispersion is also discussed.
Two-dimensional Dual-band Thin-layer Chromatographic Separation of Polynuclear Hydrocarbons
Authors: Matsushita Hidetsuru , Suzuki Yasutomo 
Published: July 2006

Abstract
A two-dimensional dual-band thin-layer chromatographic procedure for the separation of a mixture containing many polynuclear hydrocarbons is described. A chromatoplate composed of two adsorbent layers, aluminum oxide G and acetylated cellulose, is used in this chromatography. A sample containing various polynuclear hydrocarbons is first developed on an aluminum oxide G layer with n-hexane - ether (19:1, v/v) and then on an acetylated cellulose layer with methanolether-water (4:4:1, v/v). A mixture of 15 polynuclear hydrocarbons was completely separated into its components by this treatment. This method was then applied to the separation of a vacuum-sublimation extract of particulates obtained from Tokyo air. The extract was separated into 69 spots, and it was proved that several hydrocarbons, including benzo(a)pyrene, has been isolated in a pure state.
The Configuration of 6,8(9)-p-Menthadien-2,4-diols and p-Menthane-2,4-diols
Authors: Sakuda Yoshitsugu 
Published: July 2006

Abstract
The 6,8(9)-p-Menthadien-trans-2,4-diol (I) and 6,8(9)-p-menthadien-cis-2,4-diol (II) were obtained by the oxidation of l-cis-carvyl acetate with selenium dioxide. The hydrogenation of each 6,8(9)-p-menthadien-2,4-diol gave a different pair of p-menthane-2,4-diols, one pair being p-menthane-2,4-diols (III and IV) from trans-2,4-diol (I) and the other pair being p-menthane-2,4-diols (V and VI) from cis-2,4-diol (II). The absolute configurations of the p-menthane-2,4-diols (III, IV, V and VI) were assigned as follows on the basis of the chemical evidence, the IR and NMR data, and the Cotton-effect sign of the oxidation products of these isomers: III, (1S : 2R : 4S); IV, (IR : 2R : 4S); V, (1R : 2R : 4R) and VI, (1S : 2R : 4R)-p-menthane-2,4-diol. The identification of these diastereoisomeric diols III–VI made possible the assignment of a configuration to diols I and II.
Organic Syntheses by Means of Metal Complexes. II. Oxo Reaction Catalyzed by Cyclopentadienyliron Dicarbonyl Dimer
Authors: Tsuji Jiro , Mori Yoichi 
Published: July 2006

Abstract
It was found that cyclopentadienyliron dicarbonyl dimer is an active catalyst for oxo reaction and the characteristic features of the catalysis have been studied.
Study of Wall Effect on the Flow of Polyvinylpyrrolidoe Solutions in Capillary
Authors: Watanabe Takehiko , Mineshita Takeshi , Ono Sôzaburo 
Published: July 2006

Abstract
Dependence of the viscosity of the polyvinylpyrrolidone (\barMv=4.0×104 and 9.0×105) solutions on the bore-size of capillary viscometer has been studied at 35°C, in pure water, in dimethyl sulfoxide (DMSO), in water-DMSO, and in aqueous solution with various cosolutes, at various concentrations (0.5–5.0 g/100 ml). Viscosity measurements were carried out with a Maron-Belner type low shear capillary viscometer with various capillary radii (0.0190–0.0761 cm) within the shear stress range of 0.2–20 dyn/cm2 at the capillary wall. The solutions showed a behavior of non-Newtonian flow and dependence on the size of the capillary. The viscosity of the polymer solutions in DMSO, and in water-DMSO decreased with the decrease in the capillary bore-size within the range of shear stress studied, and that in pure water, although similar phenomena as above were observed in higher shear stress, increased with the decrease in the capillary bore-size at the range of the lower shear stress, and this capillary bore-size dependence could not be observed with the aqueous solutions with cosolutes. The difference in the characteristics of the capillary bore-size dependence of the viscosity may be attributed to the difference in the behavior of the polymer molecules existing near the wall at which the thermal motion of the polymer molecules will be hindered by the existence of the capillary wall. The results were represented by the modified Ree-Eyring generalized flow formula for a flow system containing one Newtonian flow unit and one non-Newtonian one which included the additional terms dependent on the capillary bore-size. The viscosity equation suitable for analysing the dependence of the viscosity on the capillary bore-size at entire ranges of the rate of shear, was derived by assuming the wall layer composed of the double layers (of thickness do and di–do) in the flowing liquid in the capillary tube, and by combining this equation with the modified Ree-Eyring equation, the values of do and di were calculated.
Electronic Spectra of Crystalline TCNQ Anion Radical Salts. II. Complex Salts
Authors: Iida Yôichi 
Published: July 2006

Abstract
The present paper deals with crystalline TCNQ anion radical “complex” salts of (M+)2-(TCNQ)3\ewdot\ewdot and M+(TCNQ)2\ewdot composed of the formally-neutral TCNQ and its anion radical TCNQ\ewdot Their crystalline electronic spectra were measured in the range between 4.0 and 30.8 kK by diffuse reflectance and in the 0.65–4.0 kK range by transmittance. None of their spectra except those of the (2 : 3) compounds were found to bear any resemblance to those in the simple salts. Although the spectra of the (2 : 3) compounds are similar to those of the simple salts with low conductivities, the former exhibit an additional weak absorption in the range lower than 6 kK. The (1 : 2) compounds with intermediate conductivities show a strong band around 3 kK, and those with high conductivities, around 2.0–2.5 kK. Their spectra are discussed on the basis of the interaction among unpaired electrons in connection with their electrical and magnetic properties. The difference in the interaction modes of the ion radicals between “simple” and “complex” salts is also speculated upon.