bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photochemical Hydrolysis of Barbitals
Authors: Otsuji Yoshio , Kuroda Tokuyuki , Imoto Eiji 
Published: July 2006

Abstract
The irradiation of barbital (BA) and N,N′-dimethylbarbital (DMBA) in aqueous alkaline media gave diethylacetylurea and N,N′-dimethyldiethylmalonarmide respectively. On the basis of the results of kinetic studies, the above photochemical hydrolyses of BA and DMBA were shown to be an attack of the hydroxide ion on the singlet excited states of BA monoanion and DMBA respectively. Such nucleophilic reagents as amines, mercaptide, and cyanide ions retarded the photochemical hydrolyses by quenching the excited state of the substrates.
New Syntheses of Vinyl Sulfides and Unsaturated Nitriles via Quaternary Phosphonium Salts
Authors: Kumamoto Takanobu , Hosoi Kazuo , Mukaiyama Teruaki 
Published: July 2006

Abstract
New methods for the syntheses of vinyl sulfides and unsaturated nitriles via quaternary phosphonium salts have been established. The reaction of isopropylidenetriphenylphosphorane with S-ethyl thiobenzoate or substituted S-ethyl thiobenzoates afforded vinyl sulfides and triphenylphosphine oxide in good yields. Further, it was found that the reaction of α-benzoylalkylphosphonium salts with sodium ethylmercaptide or potassium cyanide gave olefins, such as vinyl sulfides or unsaturated nitriles, and triphenylphosphine oxide in good yields, respectively.
Studies of Aminosugars. XIX. Syntheses of O-Benzyl-α-halogeno Derivatives of 3-Acetamido-3-deoxy- and 6-Acetamido-6-deoxy-d-glucose
Authors: Koto Shinkiti , Tsumura Takayuki , Kato Yoshinori , Umezawa Sumio 
Published: July 2006

Abstract
As a part of investigation of the synthesis and reaction of 1-halogeno derivatives of amino-monosaccharides, 3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-d-glucopyranosyl chloride and 2,3,4-tri-O-benzyl-6-(N-benzylacetamido)-6-deoxy-α-d-glucopyranosyl chloride have been synthesized. Attempts to prepare α-glycosides from these benzyl derivatives proved to be practical, giving cyclohexyl 3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-d-glucopyranoside and cyclohexyl 2,3,4-tri-O-benzyl-6-(N-benzylacetamido)-6-deoxy-α-d-glucopyranoside as main products. Removal of the masking groups gave cyclohexyl α-glucosides of 3-amino-3-deoxy-d- and 6-amino-6-deoxy-d-glucose respectively. A number of related derivatives have been described.
Studies of Aminosugars. XX. The Synthesis of 6-O-(3-Amino-3-deoxy-α-d-glucopyranosyl)-2-deoxystreptamine
Authors: Koto Shinkiti , Tatsuta Kuniaki , Kitazawa Eiichi , Umezawa Sumio 
Published: July 2006

Abstract
6-O-(3-Amino-3-deoxy-α-d-glucopyranosyl)-2-deoxystreptamine (3AD) which is a glycoside component of kanamycin A has been synthesized. Amino and hydroxyl groups of 2-deoxystreptamine were masked with carbobenzoxy and isopropylidene groups to give racemic mono-O-isopropylidene-di-N,N′-carbobenzoxy-2-deoxystreptamine with which 3-acetamido-2,4,6-tri-O-benzyl-3-deoxy-α-d-glucopyranosyl chloride was condensed by a modified Koenigs-Knorr reaction. Removal of all the masking groups followed by N-dinitrophenylation, acetylation and chromatography gave the product identical with an authentic specimen of the penta-O-acetyl-tri-N-(2,4-dinitrophenyl) derivative of the natural 3AD. The synthetic product was further led to 3AD identical with a natural sample.
Oxidation of Propylene over the Tin-Antimony Oxide Catalysts. II. Investigations of Physicochemical Properties of the Catalysts
Authors: Wakabayashi Katsuhiko , Kamiya Yoshio , Ohta Nobuto 
Published: July 2006

Abstract
The physicochemical properties of the binary system composed of Sn and Sb oxides have been investigated. The electrical conductivity increased rapidly up to 3 atom% Sb, and subsequently decreased, little by little, as the Sb oxide content in the binary system increased. The surface area also increased rapidly up to 3 atom% Sb, and in the region exceeding this content a dilution effect due to Sb oxide was observed. The behavior of the initial rate of acrolein formation as a function of the catalyst composition was fairly similar to that of the surface area. The apparent activation energies for carbon dioxide formation at first decreased, and then became nearly constant when the Sb content of the catalysts increased. On the other hand, the activation energies for acrolein formation may be considered to be always constant, independent of the catalyst composition, at about 17 kcal/mol. The activation energies for the catalyst reduction by hydrogen were 28 kcal/mol for Sn oxide, 14 for a mixture containing 25 atom% Sb, and 30 for Sb oxide. Consequently, it has been concluded from these results that it may depend on the nature of the chemisorbed oxygen which attacks propylene whether the propylene is oxidized into acrolein or into such complete combustion products as carbon dioxide.
Effect of Pressure on Graphitization of Carbon. V. Electron Spin Resonance in Hard Carbon Heat-Treated under High Pressure
Authors: Kamiya Kan-ichi , Yugo Shigemi , Inagaki Michio , Saito Hajime , Tsuzuku Takuro 
Published: July 2006

Abstract
By means of the electron spin resonance (ESR), the graphitization process of a hard carbon (phenolformaldehyde resin char) under a pressure of 5 kbar was investigated in relation to the results of the X-ray diffraction analysis. In the ESR measurement, there is observed only a sharp Lorentzian line having g-value of about 2.003 for the products heat-treated at relatively low temperatures. On the other hand, gradual increase in the heat treatment temperature (HTT) leads to the appearance of new 15–20 G wide line having g-value of about 2.01, overlapping on the sharp one, and its absorption intensity tends to increase further with HTT. The appearance of the broad ESR line has been found always being accompanied by an abrupt increase of the content of graphitic component deduced from the analysis of (002) diffraction profile. From further investigation of features of these ESR lines as a function of ambient temperature, the sharp one is concluded that it originates from the so-called localized spin centers, while the broad one from the delocalized. The coexistence of these two signals suggests that the turbostratic and graphitic parts have enough extent to prevent the motional mixing of these spin centers, which has also been verified by the X-ray diffraction analysis.
An Oxygen Concentration Profile of a MnO2 Particle after Discharge Service
Authors: Miyazaki Kazuhide 
Published: July 2006

Abstract
The behavior of oxygen in a manganese dioxide depolarizer discharged in a Leclanche-type test cell down to a cut-off voltage of 0.7 V was visually examined by means of electron probe microanalysis. The oxygen concentration profile of a typical MnO2 particle of about 50 μ in diameter showed that the relative amount of oxygen at the surface and along the pores inside was evidently reduced due to the discharge reaction invading 5 to 10 μ towards the inner part of the particle, indicating that the discharge primarily took place in these portions and involves a process of releasing oxygen from sites at the outermost surface and along the pores. The region which contains these lower oxide portions was observed to be 20–30% of the total crosssectional area, implying that the utility factor of MnO2 as a depolarizer was accordingly of the order of 20–30%. It was suggested that enhancement of the use of pores or cleavages during a discharge would generally be beneficial to the service life as a depolarizer, better than merely reducing the particle size of the material.
Rate of Electron Exchange between Cuprous and Cupric Ions in Concentrated HCl by Electron Spin Resonance
Authors: Stewart R Allan , Reeves L W , Fujiwara Shizuo 
Published: July 2006

Abstract
Contrary to previous reports, the linewidth of the electron spin resonance spectrum of cupric ion as measured in gauss between points of maximum slope is a sensitive function of ionic strength, chloride ion concentration and cuprous ion concentration. Assuming that electron spin relaxation rates do not change greatly on the addition of cuprous ion, it is possible to derive an electron exchange rate for the reaction:
Cu^++Cu^2+↔Cu^2++Cu^+
of k=1.53×109 l/mol/sec. This value is in good agreement with a previous determination of the same rate constant by McConnell and Weaver using the 63Cu nuclear magnetic resonance (0.5×108). The results for the linewidth changes can be rationalized in all cases by assuming that bridge chloride ions between two cupric ions or one cupric and one cuprous ion change drastically in concentration as such factors as ionic strength or chloride ion concentration changes. The g value of the electron (free) decreases as chloride ion is added, indicating delocalization of the unpaired electron onto chloride ligands.
A Study on the Electronic Spectra of 1-(p-Substituted phenyl)pyrroles
Authors: Matsuo Taku , Shosenji Hideto , Miyamoto Reiji 
Published: July 2006

Abstract
The longest wavelength electronic absorption band of 1-(p-substituted phenyl)pyrrole has been found to show a regular bathochromic shift as the electronegativity of the substituent on the phenyl group increases. The substituent effect is closely related to that for the intramolecular charge-transfer bands of p-substituted anilines. Therefore, the longest wavelength absorption band of 1-(p-substituted phenyl)pyrroles have been suggested to be originated from an electron transfer from the pyrryl group to the phenyl group. Only one exception is the spectra of 1-(N,N-dimethyl-p-aminophenyl)pyrrole. In this case, the longest wavelength electronic absorption band is suggested to be due to an electron-transfer from the N,N-dimethylamino group to the phenyl group.
Radiolysis of Methylcyclohexane. I. Effects of Temperature and Electron Scavengers on Hydrogen Formation
Authors: Kimura Toyoaki , Miyazaki Tetsuo , Fueki Kenji , Kuri Zen-ichiro 
Published: July 2006

Abstract
The effects of temperature and electron scavengers on the hydrogen yield in the radiolysis of methylcyclohexane have been investigated by conventional kinetic techniques. The I value for hydrogen formation from pure methylcyclohexane varied from 4.9 to 4.4 in the range from room temperature to liquid nitrogen temperature. In the iodobenzene-methylcyclohexane system, the decrease in hydrogen yield was equal to the yield of benzene produced within experimental error. It is concluded that the benzene is formed through H atom abstraction from the solvent molecules by phenyl radicals which are formed by dissociative electron attachment to iodobenzene and that the benzene yield indicates the scavenged electron yield. Furthermore, a kinetic treatment for electron scavenging in the glassy state was presented. In the N2O-methylcyclohexane system, it was found that the ratio of the nitrogen yield, G(N2), to the decrease in hydrogen yield, ΔG(H2), is 2 in the temperature range from room temperature to −140°C, 1 at −160°C, and increases from 1 to 4 with increasing N2O concentration at −196°C, respectively.
γ-Radiolysis of a Binary Mixture of Methanol and Water. The Formation of Formaldehyde in the Radiolysis of Liquid Methanol
Authors: Seki Hiroshi , Nagai Reiko , Imamura Masashi 
Published: July 2006

Abstract
The γ radiolysis of a binary mixture of methanol and water over a wide concentration range has been investigated. The observed yields of products are expressed as a linear function of the electron fraction of methanol in the mixture. The yields of molecular hydrogen were also determined. Analyzing the results on reasonable assumptions, one could obtain for neutral water, Ge\barsw=2.3–2.5 and GOHw≥2.6. It was concluded that, in the radiolysis of methanol, formaldehyde may be produced through the decomposition of CH2OH radicals in the spur region, not by the disproportionation of these radicals.
Phase Changes in the ZrO2-TiO2 System
Authors: Noguchi Tetsuo , Mizuno Masao 
Published: July 2006

Abstract
The liquidus curve in the ZrO2-TiO2 system previously reported by the present authors was again examined with a heliostat-type solar furnace in order to determine the peritectic point in the ZrO2-rich side region. Quenched specimens from the melt of the ZrO2-rich side region were analysed by the X-ray technique. The cooling curves from the melt suggested the existence of a new phase stable at higher temperatures, and a tentative phase diagram at high temperatures is presented.
Ca3(PO4)2 - CaNaPO4 System
Authors: Ando Jumpei , Matsuno Seiichi 
Published: July 2006

Abstract
As a fundamental research of a calcined defluorinated phosphate containing a small amount of sodium, the system Ca3(PO4)2(tricalcium phosphate, T) - CaNaPO4(Rhenanite, R) was studied by high temperature X-ray diffraction, differential thermal analysis, etc., and the phase diagram determined. During heating, T inverted from β to α at 1180°C, and then possibly from α to α′ at 1280°C. R inverted from β to α at 690°C. In the composition range containing R from about 10 to 98% by weight, (βT+βR), the stable phase at room temperature, inverted to (βT+αR) at 650°C. The (βT+αR) changed at 980°C to form a compound “A” Ca5Na2(PO4)4 for the sample containing 50.5% R, and (“A”+βT) for samples containing a smaller amount of R. The (“A”+βT) then changed to “A” solid solution at elevated temperatures. The crystals of “A” consisted of a superlattice of αR. “A” and the solid solution changed to αR solid solution at higher temperature. By quenching the samples containing 35 to 50.5% R from 1400°C, a single phase “A” or “A” solid solution was obtained at room temperature. The “A” solid solution was the major phase of the calcined defluorinated phosphate. During heating of samples containing more than 50.5% R, (βT+αR) changed to αR solid solution at or below 980°C; during cooling of the solid solution (“A”+βR) formed at 650°C.
Electronic Structure of Tris(α-diimine)iron(II) Complexes
Authors: Ito Tasuku , Tanaka Nobuyuki , Hanazaki Ichiro , Nagakura Saburo 
Published: July 2006

Abstract
The electronic structures of tris(α-diimine)iron(II) complexes have been investigated. The theoretical consideration has revealed that a considerable π-back donation takes place in the ground state and as a result unusually stable complexes of iron(II) are formed. The intense band which appears in the visible region has been proved to be due to the charge transfer transition from 3dπ AO (atomic orbital) of iron to the lowest vacant π MO (molecular orbital) of the ligand α-diimine. It was found both theoretically and experimentally that the π→π* transition with the lowest energy in α-diimine is polarized parallel to the nitrogen-nitrogen direction of the molecule, and that transition dipoles in the three ligands of tris(α-diimine)iron(II) ion interact to give resultant A1→A2 and A1→E transitions in the metal complex with D3 symmetry. Details of the electronic structures, including the splitting energy and the intensity of the local excitation in α-diimine molecule and the nature of the charge transfer band, have been discussed.
Studies on Separation of Amino Acids and Related Compounds. III. Separation of Diastereomers of Leucyl Dipeptides by Ion-Exchange Chromatography
Authors: Noda Kosaku , Okai Hideo , Kato Tetsuo , Izumiya Nobuo 
Published: July 2006

Abstract
A series of experiments on a column chromatography of Dowex 50 with ammonium acetate solvent systems as eluent was carried out in order to find optimal conditions for the separation of the diastereomers of leucylalanine, leucylvaline, leucylleucine and leucyltyrosine. The effects of pH concentration of the salt and alcohols in the solvent systems for the separation of the diastereomers were studied. Among many conditions tested, the change of pH in the solvent system afforded most remarkable influence for the separation; the order of elution of the diastereomers of the dipeptide was found to be inverted at near pH 5.0. On a preparative scale l-leucyl-Dl-valine was successfully separated into the two diastereomers by using a fairly large column. Attempt to separate benzyloxycarbonyl-l-leucyl-Dl-valine benzyl ester with a column of Sephadex LH-20 was described, also.
Coumarins. IV. The Acid-catalyzed Reaction of Phenols with Allyl Cyanide
Authors: Amakasu Takeshi 
Published: July 2006

Abstract
A new route to the syntheses of 4-methyldihydrocoumarins has been developed by means of the aluminum chloride-catalyzed reaction of phenols with allyl cyanide. The reaction of excess phenol with allyl cyanide in the presence of 2 equivalents of anhydrous aluminum chloride and an excess of hydrogen chloride yielded β-(p-hydroxyphenyl)-butyronitrile in a 16% yield. In contrast, the corresponding 4-methyldihydrocoumarins were obtained, together with β-arylbutyronitriles, from o- and m-cresols. p-Cresol gave rise to 4,6-dimethyldihydrocoumarin as the sole product in a 8% yield. In diisopropyl ether, resorcinol underwent a similar reaction with allyl cyanide and afforded 4-methyldihydroumbelliferone in a 50% yield.
Oxidation of Phosphites by Means of p-Quinones and Benzyl Alcohol
Authors: Mitsunobu Oyo , Kodera Kyoko , Mukaiyama Teruaki 
Published: July 2006

Abstract
Triethyl phosphite and tri-n-butyl phosphite were oxidized to the corresponding trialkyl phosphates by means of p-quinones and benzyl alcohol. On the other hand, when diethyl (N-diethyl)phosphoroamidite was treated with p-benzoquinone and benzyl alcohol, 4-ethoxyphenyl ethyl (N-diethyl)phosphoroamidate was obtained in a 69% yield and no diethyl (N-diethyl)-phosphoroamidate was isolated. The reaction of 2,3,5,6-tetrachloroquinone with diethyl benzyl phosphite in the presence of ethanol resulted in the formation of triethyl phosphate and 4-benzyloxy-2,3,5,6-tetrachlorophenyl diethyl phosphate in 16% and 68% yields respectively.
Photolysis of Nitrite Esters bearing Nitrogen on the β-Carbon
Authors: Suginome Hiroshi , Murakami Masakazu , Masamune Tadashi 
Published: July 2006

Abstract
The results of photolysis of a number of nitrite esters derived from jervine, in which the respective β-carbon of nitrite group bears nitrogen, are described. It has been found that in these nitrites when a nitrogen on β-carbon was in the amide group, the irradiation caused the cleavage of α, β-single bond to the nitrite group. The reaction is exemplified by photolysis of 3O, N-diacetyl-22,27-imino-11-oxojerva-5,13(17)-diene-3β, 23β-diol 23-nitrite ester (Ic) to afford an aldehyde II. When a nitrogen on β-carbon of nitrite was tertiary (e.g., XIb), however, no photoinduced fission of carbon-carbon bond in these nitrites was observed and the starting alcohol recovered unchanged. These results coupled with others, e.g., the result of photolysis of 3O-acetyl-N-benzoyl-22,27-imino-11-oxojerva-5,12-diene-3β, 23β-diol 23-nitrite ester (IIIf) indicate the selective cleavage of acyl-nitrogen bond followed by acidic hydrolysis to an aldehyde during chromatography, as shown in the scheme V to VIII. It is noted that this reaction is contrasted with the reported results with regard to photolysis of nitrites bearing oxygen in place of nitrogen.
Analyses of Organic Soils Extracted from Naturally-soiled Cloths
Authors: Tsunoda Teruo 
Published: July 2006

Abstract
The analyses of organic soils extracted from naturally-soiled chloths were carried out by IR spectroscopy, gas chromatography, thin-layer chromatography (TLC), and gel filtration. The fatty-acid constituents involved in organic soil were determined by gas chromatography. The presence of triglycerides, cholesterol and its ester, and such hydrocarbons as paraffin and squalene in organic soil was also found by means of TLC. In gel filtration, two peaks were found in elution diagrams of the detergent solution after washing naturally-soiled cloths. The ultraviolet spectra, which were measured for the effluent corresponding to each peak, indicated that the nitrogen compound involved in each effluent is probably a protein-lipid complex such as lipoprotein. The nitrogen content in each effluent was also determined by the micro-Kjeldahl method. A smaller nitrogen content was given for the effluent corresponding to the first peak than for that of the second peak. The nitrogen compound involved in the effluent for the first peak was harder to remove from cloths than that for the second peak.
Thermal Decomposition of Ketene in Shock Waves
Authors: Tsuda Morizo , Kuratani Kenji 
Published: July 2006

Abstract
With the use of a single pulse shock tube of a magic hole type, the thermal decomposition of ketene was studied at temperatures from 1140 to 1530°K. The formation of carbon monoxide, that is, the disappearance of ketene, followed a kinetic order of 1.5 with respect to ketene and its rate constant was represented by
k=10^14.2exp[(-65600±1100)/RT]l^1/2mol^-1/2sec^-1.
The thermal decomposition of mixtures of ketene and ethylene in argon was also studied, and the formation of methylene radicals during the pyrolysis of ketene is deduced from the presence of propylene and cyclo-propane in the products of these three component reactants. The rate of ketene disappearance was not affected by the addition of ethylene, or nitric oxide. A chain mechanism in which methylene radicals play a principal part, and a combined molecular mechanism of first, and second orders were proposed tentatively to explain the observed 1.5th order reaction rate.
Adsorption Behavior of Hydrogen and Carbon Monoxide over Zinc Oxide in the Mixed Gas Adsorption and during the Methanol Decomposition Reaction
Authors: Tsuchiya Susumu , Shiba Tadao 
Published: July 2006

Abstract
Adsorption of hydrogen and carbon monoxide at the different situations has been investigated with zinc oxide which is the principal component of ordinary methanol synthesis catalysts. In the simultaneous adsorption of hydrogen and carbon monoxide the mutual interaction was also observed. The results were explained as the displacement effect as well as the enhancement took place in a certain region of the partial pressures. Adsorption measurements during the decomposition reaction suggest that in initial state the adsorbed species are mostly the adsorbed methanol and that the step of the decomposition of it is the rate-determining step of the overall reaction. The mechanism of methanol synthesis over zinc oxide is suggested to proceed in the similar way as on the three component catalyst previously used.
On the Glass Transition Phenomenon of Isopentane
Authors: Sugisaki Masayasu , Adachi Keiichiro , Suga Hiroshi , Seki Syûzô 
Published: July 2006

Abstract
Heat capacity measurement of isopentane was carried out for crystalline, liquid, glassy, and supercooled liquid states in the temperature region between 13 and 300°K. The glass transition phenomenon of isopentane was found around 65°K with drastic heat capacity change of 68.20 J/mol degK. This glass transition phenomenon is tentatively interpreted in terms of the Adam and Gibbs theory. The value of Tg⁄T2, the ratio of glass transition temperature Tg, and the temperature of disappearance of the configurational entropy of the supercooled liquid T2, for isopentane was found to be 1.30 which is concordant with the value cited by Adam and Gibbs. The residual entropy at absolute zero of the glassy isopentane was shown to be 14.06 J/mol degK. In addition the irreversible production of entropy during the glass transition intervals was found to be 0.08 J/mol degK. It is concluded that the neglect of the irreversible production of entropy leads no significant error in determing the residual entropy.