bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Phosphorescence Bands of Anthraquinone in Crystalline Solvents at 77°K
Authors: Kuboyama Akira 
Published: July 2006

Abstract
The phosphorescence bands of anthraquinone in the solvents used in this work are all safely assigned to the π*→n bands on the basis of their short lifetimes. In n-paraffins (n-hexane, n-heptane, and n-octane), two phosphorescence bands which are close to each other are found. Considering the dependence of the relative intensities of these two phosphorescence bands on the carbon-numbers of the n-paraffins, it is assumed that the longer- and the shorter-wavelength bands are due to the anthraquinone molecules with the C–O bond axis parallel to and perpendicular to the longitudinal axis of the planar zig-zag form of the n-paraffin molecules in the n-paraffin crystals respectively. In chloroform and dioxane, a broad phosphorescence band shows a blue-shift relative to the corresponding band in the alkane solvents. In chloroform a sharp phosphorescence band was also observed for a solution which was rapidly cooled. This sharp band is assumed to be due to the anthraquinone molecules with a certain geometry relative to the surrounding chloroform molecules.
Electrical Conductivity of Graphite Bromine Lamellar Compounds
Authors: Sasa Tadashi , Takahashi Yoichi , Mukaibo Takashi 
Published: July 2006

Abstract
Polycrystalline graphite was allowed to react with bromine vapor, and the change of its electrical conductivity during the course of bromination and debromination was studied. The graphite was found to behave in two different ways depending on the process of bromination. When the vapor pressure of bromine was changed stepwise, following the equilibrium line of bromine absorption of graphite, the electrical conductivity showed a reversible change. On the other hand, when a graphite sample was brominated with the saturated vapor, an increase of the electrical conductivity steeper than that of the former case was observed. These results were discussed in relation to the structural analysis of the brominated graphite. A metastable phase of graphite bromide, the electrical conductivity of which remained unchanged in spite of a considerable increase of absorbed bromine, was found. The electrical conductivity of the residue compounds was also investigated, and a steep decrease was observed at high concentrations of bromine.
Chemi-ionization of Cs*(82P1⁄2) with Cs and Foreign Gases
Authors: Ono Yoko , Koyano Inosuke , Mori Yuji , Tanaka Ikuzo 
Published: July 2006

Abstract
Chemi-ionization has been studied by the collision of the excited atom of cesium (82P1⁄2), whose energy is lower by 0.7 eV than its ionization energy, with cesium, rare gases or simple molecules. The mechanisms for the chemi-ionization, and quenching processes occurring simultaneously were set up and the cross sections of the processes have been determined. Since the pressure effects of added gases to the absorption coefficient of Cs at 3888 Å from the He lamp could not be neglected, suitalbe corrections were made.
Electronic States of p-Chloranil and Its Anion-Radical as Revealed by Their Infrared Spectra
Authors: Iida Yoichi 
Published: July 2006

Abstract
The infrared spectra (650–4000 cm−1) of p-chloranil and its anion-radical were measured. Appreciable frequency differences between their corresponding bands were noted. The fundamental frequencies were assigned, and the simple UBFF’s were determined for both the neutral and anion-radical molecules. Their stretching force constants for the bonds in the conjugated systems are related to the bond orders. The values of the bond orders thus obtained for p-chloranil and its anion-radical were in good agreement with those evaluated by the molecular-orbital calculation, except for the C=O bond in the anion-radical. In view of these results, it was concluded that the difference in the infrared spectra between these two molecules was almost entirely attributable to the difference in their electronic structures caused by an odd electron on the p-chloranil anion-radical. The bond lengths were also estimated on the basis of the bond orders. It was shown that the application of this method might bring valuable knowledge on the molecular and electronic structures of ion-radicals as well as of neutral molecules in general.
The Effect of Impurities upon the Physical Properties of Silica Gel by the Heat-Treatment
Authors: Muroya Masaaki , Kondo Seiichi 
Published: July 2006

Abstract
The effects of various kinds of inorganic salts upon the physical properties of silica gel heated in the range up to 1200°C were studied. We measured the polymorphic behavior by means of X-ray diffraction, the simultaneous measurement of the differential thermal analysis, and the thermogravimetric analysis, and the specific surface area by means of the BET N2 method and by means of studying the water-adsorption capacity. The cationic impurities which were found to have strong effects upon the physical properties mentioned above are Na+, K+, Ca2+, Pb2+, Cd2+, Zn2+, and Sb3+. Cations such as Al3+, Cr3+, Mn3+, and Co2+ were shown to have weak but positive effects upon the physical properties of silica gel.
Spectroscopic Studies of Polynuclear Complexes. II. Preparation and Optical Resolution of μ-Amido-μ-superoxo and μ-Amido-μ-peroxo Tetrakis(α-di-imine)dicobalt(III) Ions
Authors: Sasaki Yoichi , Fujita Junnosuke , Saito Kazuo 
Published: July 2006

Abstract
New binuclear cobalt(III) complexes of the type, [L2Co(μ-NH2,O2)CoL2](ClO4)n, where L is 1,10-phenanthroline or 2,2′-bipyridyl, and n=3 and 4, correspond to the so-called μ-peroxo and μ-superoxo form, respectively, were prepared and resolved into their optical isomers. Their absorption spectra have been compared with those of analogous ethylenediamine complexes and the structures have been discussed. The absolute configuration of these complexes has been determined by their circular dichroism spectra. The μ-peroxo complexes seem to be more stable than the corresponding μ-superoxo complexes in aqueous solution.
4-Alkyloxazolidinedione. VI. The Polymerization of α-Amino Acid N-Carboxy Anhydride
Authors: Oya Masanao , Tomizawa Mayumi , Uno Keikichi , Iwakura Yoshio 
Published: July 2006

Abstract
The relationships between the polymerization solvents and the conformation of the polypeptides formed were studied on the basis of the infrared absorption spectra and the X-ray diffraction diagrams of the polymers. Poly-l-α-amino-n-butyric acid and poly-l-n-valine, prepared in dimethylsulfoxide (DMSO) as a polymerization solvent, formed β-conformation, but the respective polypeptides obtained in acetonitrile had an α-conformation. The conformational structure of poly-l-α-amino-n-butyric acid changed from β to α upon reprecipitation from a solution in dichloroacetic acid with ether. On the other hand, the conformational structure of poly-Dl-α-amino-n-butyric acid did not change upon reprecipitation from a solution in formic acid and dichloroacetic acid.
Liquid Phase Chlorination of Olefins with Cupric Chloride. II. Stereochemistry of the Reactions of 2-Butenes and Cyclohexene
Authors: Koyano Takashi 
Published: July 2006

Abstract
Chlorination of cis-and trans-2-butenes with cupric chloride yields a mixture of meso- and dl-2,3-dichlorobutanes with meso/dl ratio of about 60/40, which is almost independent of the starting olefin configuration. For cyclohexene, trans-1,2-dichlorocyclohexane is accompanied with the cis-dichloride, the amount of which depends upon the solvent polarities. In all cases the starting olefins and the product dichlorides are sufficiently stable under the reaction conditions. The results indicate that open ionic intermediates are involved in the chlorination of simple olefins in liquid phase reaction.
Structure and Reactivity of α,β-Unsaturated Ethers. XI. Cationic Copolymerization and Acetal Addition of cis- and trans-Sthyl Ethyl Ethers
Authors: Okuyama Tadashi , Asami Nobuhiro , Fueno Takayuki 
Published: July 2006

Abstract
The cationic copolymerization between cis- and trans-styryl ethyl ethers in methylene chloride was investigated in the temperature range from −70 to 0°C with boron trifluoride etherate as catalyst. It was found that at lower temperatures the trans ether is more reactive than its cis isomer, although the relative reactivities are reversed at 0°C. Addition reactions of various acetals to cis- and trans-styryl ethyl ethers were carried out at 0°C with the same Lewis acid as catalyst. The relative cis-trans reactivities are largely dependent on the bulkiness of an attacking oxycarbonium ion. It was concluded that the cis isomer, which is electronically more reactive toward cations, is liable to suffer adverse steric effect, especially when the attacking carbonium ion is bulky.
Charge-Transfer Interaction and Chemical Reaction. II. Interaction of s-Triaminobenzene with Several Electron Acceptors
Authors: Yamaoka Tsuguo , Nagakura Saburo 
Published: July 2006

Abstract
The charge-transfer interaction was studied for systems including s-triaminobenzene as electron donor. The formation of 1 : 1 stable outer (π,π) complexes at room temperature was observed for the systems including s-trinitrobenzene, trininitrotoluene and tetracyanobenzene as electron acceptors. From the analysis of the observed absorption intensities and peak positions of charge-transfer bands, the equilibrium constants of these complexes were determined and the ionization potential of s-triaminobenzene was estimated to be 7.3–7.4 eV. Chloranil was found to form a stable outer (π,π) complex with s-triaminobenzene only at low temperature, and to be led to a substitution reaction by raising the temperature. The spectrum of the reaction intermediate, the inner (σ) complex of s-triaminobenzene with chloranil, was observed at ∼500 mμ. A tentative reaction mechanism was proposed.
Steric Structure of l-Proline Oligopeptides. IV. Proton Magnetic Resonance Studies of l-Proline Oligopeptides
Authors: Okabayashi Hirofumi , Isemura Toshizo 
Published: July 2006

Abstract
The NMR spectra of t-amyloxycarbonyl-l-proline oligopeptides were measured and compared with those of two poly-l-prolines, I and II. The α-CH resonance peaks of the oligopeptides were observed at sheilding values of 5.2 and 5.4 ppm, values which were in accord with those of the α-CH resonance peaks of the poly-l-prolines I and II, respectively. The behavior of the α-CH peaks was related to the conformation of the l-proline oligopeptides. Moreover, the contribution of the two terminal l-proline residues to the α-CH resonance peaks was discussed.
High Resolution NMR Study of Vinyl Chloride-Ethylene Copolymers
Authors: Misono Akira , Uchida Yasuzo , Yamada Kunikazu 
Published: July 2006

Abstract
The high resolution NMR spectra of vinyl chloride-ethylene copolymers obtained by trialkylboron catalyst have been analyzed. The copolymer composition could be determined from the resonance peak area, and the monomer reactivity ratios thus obtained were in good consistency with those determined from the results of elementary analysis. The fine structure of the copolymers have been elucidated in terms of the run number concept, and the distribution of dyads as well as the average sequence lengths of the monomer unit have been determined. It was found that the observed values fitted theoretical values, indicating that a terminal model holds in this copolymerization.
Studies on the Effect of Some Anionic Detergents on the Stability of Emulsions Stabilised by Partially Flocculated Sols
Authors: Jain S P , Srivastava S N 
Published: July 2006

Abstract
A partially flocculated Fe(OH)3 sol has been used as an emulsifying agent to stabilize toluene/water system. The electrophoretic mobilities of the emulsion thus obtained in the presence of different anionic detergents have been measured microelectrophoretically and from these values the zeta potentials have been calculated. At the charge reversal concentrations the adsorption and free energy constants were calculated. From the surface potential values the repulsion and attraction energies were evaluated which clearly showed that the flocculation occurrs in the secondary minima. The operating van der Waals constant A has been estimated by correlating the results of degree of aggregation obtained haemocytometrically with the theoretical values. It was found to be 1.05×10−12 erg. The values of interfacial tension have been reduced by the addition of these detergents which are directly connected with the chain length of the detergent and adsorption characteristics.
Surface Activities of Nonionic Polymeric Surfactants
Authors: Nakamura Masao , Sasaki Tsunetaka 
Published: July 2006

Abstract
The relationship between surface activity and molecular structure has been studied for the nonionic polymeric surfactants which have 2,3,4 or 6 branches of polypropylene glycol-polyethylene glycol (PPG-PEG) chain in their molecules. A linear relation, 1⁄Δγ=A+B·x⁄y has been found to hold for each series, where Δγ is the surface tension depression of surfactant solution of a given concentration from that of water, x⁄y is the molecular structure index, in which x is the weight percent of PEG group in a molecule and y is the molar weight of PPG part, and A and B are constatns. Constant A, being equal to 0.025 cm/dyn, is independent of the concentration and the number of PPG-PEG branches and corresponds to the reciprocal of surface tension lowering of an aqueous solution of infinitely large PPG polymer. Constant B decreases linearly with the logarithm of molar concentration, and increases with the number of branches. It also depends on the hydrophilic nature of the central group of molecule.
The Mechanism of the Reaction between Molecular Hydrogen and the Electron Donor-Acceptor Complexes (1:1 and 1:2) of Various Aromatic Hydrocarbons with Sodium
Authors: Ichikawa Masaru , Soma Mitsuyuki , Onishi Takaharu , Tamaru Kenzi 
Published: July 2006

Abstract
The mechanism of the reaction between molecular hydrogen and the electron donor-acceptor complexes (A−Na+ and A=2Na+) of various aromatic hydrocarbons (A) with sodium were studied kinetically and spectroscopically. The relative activity of each electron donor-acceptor (EDA) complex for the hydrogen uptake was associated with its electronic properties, especially with the reduction potential of its anion. It was found that the hydrogen molecule reacts more readily with stronger electron-donating EDA complexes, whose anions have higher reduction potentials. It was also suggested that, on the hydrogen adsorption over the A−Na+ and A=2Na+ films (or in their solutions), the corresponding monohydroanion complexes (AH−Na+) and NaH were produced as follows :
&2A^-Na^++H_2=AH^-Na^+NaH+A
&A^=2Na^++H_2=AH^-Na^++NaH
The behavior of AH−Na+ was closely correlated with the localization energies of electrons in the anions of the aromatic hydrocarbons.
Evaluation of Softness from the Stability Constants of Metal-ion Complexes
Authors: Misono Makoto , Saito Yasukazu 
Published: July 2006

Abstract
Utilizing the dual parameter equation we derived previously, we have evaluated quantitatively softness or class (b) character of metal ions on the basis of the original criteria of soft-hard classification, viz., the stability of metal-ion complexes. Various softness parameters proposed so forth have been proved insufficient to describe softness quantitatively, although they are useful for a rough classification of metal ions into soft and hard acids. Discussion is also given concerning origin of softness, especially from the viewpoint of its closs correlation with the solvation effect.
An Electron Spin Resonance Study of the 5,12-Dihydrotetracene Radical Anion and Its Ion Pairs with Alkali Metal Cations
Authors: Iwaizumi Masamoto , Isobe Taro 
Published: July 2006

Abstract
The 5,12-dihydrotetracene radical anion and its ion pairs with alkali-metal cations have been Investigated by electron spin resonance (ESR). It has been found that the frequency of the inversion of the radical molecule is &gt;&gt;108 Hz and that the unpaired electron is distributed between the benzene and naphthalene rings. Such a distribution of the unpaired electron between the two conjugated systems is assumed to occur via a hyperconjugation mechanism. On the other hand, it was observed that the proton hyperfme splittings of the radical anion are appreciably affected by the association of an alkali-metal cation. In the case of the 5,12-dihydrotetracene-potassium ionpair in THF, the hyperfine components of the methylene protons show an alternating line-width effect. On the basis of the observed effects of the alkali metal cations, a model of the ion-pair structure is proposed, and the alternating line-width effect is explained in terms of an intramolecular migration of the potassium ion from one side of the molecular plane to the other. The activation energy of this motion of the potassium ion has been estimated to be 3.1±0.2 kcal.
The Radiolysis of Liquid Nitrogen Containing Hydrocarbons. II. Acetonitrile Formation from the Solution of Ethylene
Authors: Oka Takefumi , Sato Shin 
Published: July 2006

Abstract
The 60Co γ-radiolysis of liquid nitrogen containing ethylene has been reinvestigated in order to elucidate the mechanism of the formation of nitrogenous products. When the conversion of ethylene was 10%, the G-values of hydrogen cyanide and acetonitrile were 0.21±0.03 and 0.05±0.01 respectively. The isotopic distributions in acetonitrile, n-butane, and acetylene were examined by using an equimolar mixture of C2H4 and C2D4 as the solute. From the analysis of these distributions, it has been concluded that acetonitrile is produced mainly from the reaction between nitrogen atoms and ethyl radicals.
Sound Velocity in Polyoxyethylene(6)laurylether Aqueous Solution
Authors: Nomoto Otohiko , Endo Harumi 
Published: July 2006

Abstract
The sound velocity and density of polyoxyethylene(6)lauryether and its aqueous solutions are measured, and the adiabatic compressibility is computed from these results. The virtual sound velocity was calculated in ideal mixtures by using Kudriavtsev’s formula, and above 33°C for ideal suspensions by the use of the equation of Urick and Ament for dispersed systems. Some deviations in the experimental velocity from the calculated value are ascribed to the interaction energy of mixing. This energy, or the heat of the hydration of a nonionic surfactant, is obtained as a function of the temperature. The diagrams of the density, sound velocity, and adiabatic compressibility vs. the temperature at various concentrations always exhibit a common crossing point, nearly at the cloud point. It may thus be concluded that the measurements of the sound velocity and density give a new method for determining the cloud point.
The Interaction of Oxygen with Organic Molecules. III. Electron Transfer between Oxygen and Aromatic Amines Studied by Flash Technique
Authors: Hori Mitsufusa , Itoi Hiroyasu , Tsubomura Hiroshi 
Published: July 2006

Abstract
Flash photolysis of aniline derivatives in various solutions has been studied in oxygenated and deoxygenated conditions. Absorption spectra of the triplet states appeared in deoxygenated liquid paraffin solutions, but no transient absorption was observed in the oxygenated liquid paraffin solutions. Transient spectra, due to the cations of the anilines, were observed in deoxygenated ethanol solutions, but none in oxygenated ethanol. In highly polar solvents—acetonitrile, water, and formamide—either deoxygenated or oxygenated, the cation was observed. In the case of oxygenated solutions, the initial yield of the cation was found to be proportional to the intensity of the flash light, indicating that the ionization is a one-photon process. These results, together with the previous findings that the photo-ionization of organic molecules in solutions are caused by the two-step, biphotonic excitation processes strongly suggest that the charge transfer states are formed between the aromatics and the oxygen molecule, either by direct excitation or via the interaction of excited anilines and the ground state of oxygen, and the charge transfer states then lead to the solvated cations and anions in highly polar solvents. The decay of the ions have been found to follow the second order kinetics.
The Photometric Determination of Minute Amounts of Iodine in Silicate Rocks
Authors: Yonehara Norinobu , Yoshida Minoru , Iwasaki Iwaji 
Published: July 2006

Abstract
A rapid and sensitive method for the determination of minute amounts of iodine in silicate rocks has been developed. A rock was fused with potassium hydroxide, and the cake was treated with water and sulfuric acid. The iodine in the solution was reduced to iodide by sodium sulfite, and was then oxidized to free iodine by sodium nitrite. The free iodine thus obtained was extracted with carbon tetrachloride and then back-extracted with a sodium hydroxide solution. The iodine in this aqueous layer was determined photometrically by a method based on the catalytic effect of iodine on the color-fading of ferric thiocyanate. By the proposed method, amounts of iodine as low as 0.007 μg in a 1-g sample of silicate rocks can be determined. Application to some igneous rock samples gave results with a relative standard deviation of less than 7.2%, except for very low concentrations.
Reactions of Potassium Iron Carbonylate with Olefins and Alkyl Halides
Authors: Masada Hiromitsu , Mizuno Mitsuyuki , Suga Sohei , Watanabe Yoshihisa , Takegami Yoshinobu 
Published: July 2006

Abstract
Potassium iron carbonylate, KHFe(CO)4, reacted with ethyl acrylate, crotonate, 3-butenoate, styrene, and α-olefins at 40–70°C under an atmosphere of carbon monoxide. Methylmalonate was selectively obtained from the acrylate by treatment of the reaction mixture with an alcoholic iodine and hydrogen chloride solutions. Dipotassium iron carbonylate, K2Fe(CO)4, reacted with β-bromopropionate to give mainly methylmalonate. Isomerization of β-ethoxycarbonylpropionyliron carbonylate to the α-isomer occurred readily in contrast to isomerization of acylcobalt carbonyl. Both crotonate and 3-butenoate gave ethylmalonate as a major product and methylsuccinate and glutarate as minor ones. The results suggest that α-ethoxycarbonylbutyliron carbonylate is more predominant than the corresponding β- and γ-isomers in equilibrium state. This is in striking contrast to the case of acylcobalt carbonyl. Styrene yielded two isomeric aldehydes, α- and β-phenylpropionaldehydes. Ethyl caproate and enanthate were obtained from 1-pentene and 1-hexene, respectively in poor yield.
Polyamino-Zucker. V. Modellreaktionen zur Aminierung cyclischer Nitrodiole
Authors: Nakagawa Toshio , Sakakibara Tohru , W. Lichtenthaler Frieder 
Published: July 2006

Abstract
On treatment of lr,3c-diacetoxy-2t-nitrocyclohexane (3) or its 1,3-dimesyloxy analogue 4 with primary amines or ammonia, nitrodiamines (5–11) are obtained via an elimination-addition mechanism. Similar aminations of lr-methyl-1-nitrocyclohexane-2c,6c-diol (15) or its di-O-acetate 16 give C-methyl branched nitrodiamines (12–14), which are also formed by reaction of glutaraldehyde with nitromethane and amines. Structures and conformations of the products obtained were deduced from IR and NMR data.