bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enthalpy-Controlling Adsorption of Hydrocarbons on 1,3,5-Trinitrobenzene as Revealed by Gas Chromatography
Authors: Akimoto Masamichi , Echigoya Etsuro 
Published: July 2006

Abstract
Equilibrium adsorption constants for a series of olefins and paraffins on 1,3,5-trinitrobenzene were enhanced upon increasing the electron-donating nature of the hydrocarbons; the trend in the adsorption constants was entirely due to variations in the enthalpy change of adsorption rather than the entropy one. These results are characteristics of the adsorption in which the donation of electrons from a hydrocarbon molecule is strongly predominant.
Amination of Decyl Alcohol over the Binary Metal Oxide Catalysts
Authors: Takita Yusaku , Nishida Yasuo , Seiyama Tetsuro 
Published: July 2006

Abstract
Catalytic amination of decyl alcohol was examined over binary oxide catalysts containing molybdenum, and the selective formation of decylamine was observed over TiO2-, SnO2-, and Fe2O3–MoO3 catalysts. The reaction was often accompanied by the formation of 1-decene. It was found that catalytic activity for the amination of aliphatic alcohol was associated with the acidic property of metal oxide catalysts.
The Infrared and Raman Spectra of p-Azoxyanisole in the Crystalline, Nematic and Isotropic Liquid Phases
Authors: Shibata Kazuo , Kutsukake Masaki , Takahashi Hiroaki , Higasi Keniti 
Published: July 2006

Abstract
The infrared and Raman spectra of p-azoxyanisole were measured in the crystalline, nematic, and isotropic liquid phases. In the internal vibrational region, abrupt changes in intensity were observed at the crystalline-nematic phase transition; however, no appreciable change was detected at the nematic-isotropic liquid phase transition. In the external vibrational region, some of the Raman lattice bands, which eventually vanish in the isotropic liquid phase, persist in the nematic phase, while some of the infrared lattice bands disappear and a new band appears as the crystalline-nematic phase transition point is reached and traversed. The assignments of the infrared and Raman bands which appear or disappear in the nematic phase are discussed.
Kinetic Studies of the Crystallization of Vitreous Beryllium Fluoride
Authors: Tamura Seiichi , Yokokawa Toshio 
Published: July 2006

Abstract
The kinetics of the crystallization of vitreous beryllium fluoride were studied using the quantitative X-ray diffraction and calorimetric methods. Analysis of the data using the Johnson-Mehl-Avrami equation shows that the crystallization proceeds through spherulitic growth. The activation energy of 222 kJ mol−1 was obtained from the temperature dependence of the crystallization rate using a modified Johnson-Mehl-Avrami equation.
Composition of Single Crystals of Chromium Chalcogenide Spinels Grown by Chemical Vapor Transport
Authors: Ametani Kohei 
Published: July 2006

Abstract
Compositional analyses using atomic absorption spectrophotometry were carried out on the vapor-phase grown single crystals of copper-based spinels with the nominal formulas such as CuCr2S3Cl, Cu1−xFexCr2S4 (x≤1), Cu0.5In0.5Cr2S4, CuCr2Se3Cl, and CuCr2Se3Br, and the cadmium-based spinels of CdCr2S4 and CdCr2Se4, including crystals doped with indium, silver, and copper. The grown crystal usually had a composition different from the nominal formula and a tetrahedral-site deficiency of the copper-based spinels is reported for the first time. All crystals of Cu1−xFexCr2S4 and Cu0.5In0.5Cr2S4 were contaminated with a considerable amount of chlorine and some of the crystals had a substantial cation deficiency on the tetrahedral sites; the cation deficiency increases with increasing copper or chlorine content. For the CuCr2S3Cl and CuCr2Se3Br crystals, a large copper deficiency was also found while the halogen content was close to that expected for the nominal compositions, or somewhat higher. Of all the copper-based spinels, the least tetrahedral-site deficiency was observed in the CuCr2Se3Cl crystals, but the chlorine content was much less than the stoichiometric content. The cadmium-based spinels usually satisfied the stoichiometric formula CdCr2S4 or CdCr2Se4.
Chemical Synthesis of N-Acetylmuramyl Peptides with Partial Structures of Bacterial Cell Wall and Their Analogs in Relation to Immunoadjuvant Activities
Authors: Kusumoto Shoichi , Tarumi Yuzo , Ikenaka Kazuhiro , Shiba Tetsuo 
Published: July 2006

Abstract
N-Acetylmuramyl peptides of successive length corresponding to the partial structures of cell wall in Staphylococcus aureus were synthesized in order to elucidate the minimum effective structure responsible for immunoadjuvant activity of bacterial cell walls. In view of the finding that N-acetylmuramyl-l-alanyl-d-isoglutamine was the least structure moiety for exhibition of the activity, nine analogs of either N-acetylmuramyl amino acid or N-acetylmuramyl dipeptide were also synthesized.
2-Chloro-1,3,5-trithiane and 2-Chloro-1,3-dithiane. Their Ionic Dissociation and Reactions with Nucleophiles
Authors: Arai Kazutaka , Oki Michinori 
Published: July 2006

Abstract
2-Chlorol,3,5-trithiane and 2-chloro-1,3-dithiane have been prepared by chlorination of the corresponding polythianes with N-chlorosuccinimide. These chlorides afford various substitution products when treated with nucleophiles, whereas nuclear substitution of the aromatic ring occurs when the chlorides are treated with phenol or N,N-dimethylaniline. 1H NMR spectra of these chlorides show remarkable solvent dependence which is explained by assuming ionic dissociation of the chlorides to produce polythianyl cation and chloride anion. Free energies of activation for the dissociation in various solvents indicate that the dissociation of 2-chloro-1,3,5-trithiane is more sluggish than that of 2-chloro-1,3-dithiane. The results are attributed to the difference in availability of electrons on the sulfur atoms in two systems.
Preparation and Properties of Cobalt(II) and -(III) Complexes of (2-Aminoethylthio)acetic Acid
Authors: Hori Kiichi 
Published: July 2006

Abstract
The cobalt(II) and -(III) complexes of (2-aminoethylthio) acetic acid (HL), [CoL2]·H2O, trans-(N)-[CoL2]Cl and cis(N)-[CoL2]Cl·2H2O were prepared and characterized. These complexes are octahedral in which the ligand is coordinated through the N, S and O atoms as a terdentate ligand.
Structure of C-2801X, a New Cephamycin-type Antibiotic
Authors: Fukase Hiroshi , Iwasaki Hidesuke 
Published: July 2006

Abstract
The C-3 side chain moiety of C-2801X, a new cephamycin-type antibiotic, was almost quantitatively obtained by Dowex 50-catalyzed hydrolysis, and its structure was established as 3,4-dihydroxy-α-methoxycinnamic acid (I) by spectroscopic analyses and synthesis. The full structure of C-2801X was also assumed to be XIII by NMR analysis.
Preparation of Reinforcing Fillers from Japanese Acid Clays with Lime and by Calcination. IV. Investigation on the Structure, Physicochemical Properties and Morphology of M Hard Clay in Relation to the Reinforcing Effect
Authors: Rai Hideki , Yamada Junkichi 
Published: July 2006

Abstract
In order to find the optimum conditions for the preparation of satisfactory reinforcing filler from Matsune (M) acid clay, two series of fillers of M hard clay (CaO 0–9%: drying 110 °C, 5 hr for M-1 series; calcination 600 °C, 1.5 hr for M-2 series: wet ball-milling 6–24 hr) were investigated with respect to their structure, physicochemical properties and morphology. Treatment with hydrated lime (CaO 3%), followed by calcination (600 °C, 1.5 hr) and mechanical disintegration (wet ball-milling 18 hr) was found to give good results. Calcination after the lime treatment gives rise to adequate dehydroxylation as well as dehydration of the montmorillonite, calcium silicate hydrates (CSH) and excess silica remaining. This process helps to restrain the great surface activity of acid clay and facilitate pulverization of the final products combined with the effect of inhibiting polycondensation of the montmorillonite and α-cristobalite due to an even formation of the CSH distributed on the interlayer surfaces and the interfaces of the minute crystallites.
The Many-body Effects in (N2)n Systems
Authors: Hashimoto Masao 
Published: July 2006

Abstract
Many-body effects in (N2)n systems are discussed on the basis of CNDO/2-Clementi SCF calculations of the deviation from the pairwise additivity. The manybody effects cancel each other out, and this makes the deviation from the pairwise additivity only a small percentage of the pairwise interaction in the rather high n-mers.
Rearrangement of 4,5-Benzo-3-thiatricyclo[4.1,0.02,7]heptenes Promoted by Butyllithium: A New Synthetic Route to 3,4-Benzo-2-thiabicyclo[3,2.0]hepta-3,6-dienes
Authors: Tatsuoka Toshio , Murata Ichiro 
Published: July 2006

Abstract
The reaction of 4,5-benzo-3-thiatricyclo-[4.1.0.02,7]heptenes (1a–d) with butyllithium followed by quenching with water or methyl iodide at −60 °C gives the expected bridgehead substituted products, whereas the same reaction conducted at somewhat higher temperature gives the skeletal rearrangement products, 3,4-benzo-2-thiabicyclo-[3.2.0]hepta-3,6-dienes (2a–f), almost quantitatively. A mechanism in line with the results is proposed.
New A-nor-B-homo-ent-Kauranoids (Grayanotoxin XVI and XVII) from Leucothoe Grayana Max.
Authors: Gasa Shinsei , Ikeda Ry\={u}z\={o} , Hamanaka Nobuyuki , Matsumoto Takeshi 
Published: July 2006

Abstract
Two physiologically active diterpenoids, grayanotoxin XVI and XVII, have been isolated from Leucothoe grayana Max., and the structures have been determined to be 6-O-acetylgrayanotoxin II and 3,6-didehydrograyanotoxin III respectively on the basis of spectral and chemical evidence.
Adsorption and Desorption of Molecular Oxygen in Solid State of Polymeric Hemochrome
Authors: Honda Kenji , Hata Seiji , Tsuchida Eishun 
Published: July 2006

Abstract
The oxygenation of a pyridine-hemochrome bound to a polymer ligand has been studied in solid state. The oxygenation rate and the amount of oxygen adsorbed were determined by volumetry. The rate of adsorption of oxygen depends upon the structure of polymer matrix. Pyridine hemochrome included in a polyion complex takes up oxygen more rapidly than others. The rate of adsorption depends a great deal upon the surface condition of polymer matrix in case of oxygen binding in solid state. The degree of oxygenation was nearly equal in all cases. The difference in the rate of adsorption of oxygen may be due to the difference in gas permeability of the polymer matrix. This was supported by the fact that the hemochrome bound to a porous polymer matrix adsorbs oxygen more rapidly than the hemochrome bound to a non-porous polymer matrix. The surface condition of the polymer matrix greatly affects the reversibility of oxygenation.
Heteropolytungstates Containing Cobalt(II) or Cobalt(III)
Authors: Komura Akitoshi , Hayashi Mutsuo , Imanaga Hiroto 
Published: July 2006

Abstract
The reactions of tungstophosphate with cobalt ion and the properties of heteropolytungstates containing cobalt have been investigated. Unsaturated heteropolyanion PW11O397− produced by the partial degradation of the parent 12-tungstophosphoric acid reacts with cobalt ion to give 11-tungstocobaltophosphate PCoW11O40H25−. Discussion is given on the presence of cobalt in the heteropolyanion and on the above reaction. Both 12-tungstocobaltate-(II) and -(III) are very resistant to acid, but 11-tungstocobaltophosphates lose cobalt ion in strongly acidic solutions to give the parent 12-acid. Some aspects of the spectra of the heteropolytungstates, in which cobalt(II) and cobalt(III), respectively, are present in the specific site, are discussed.
Partial Molal Volumes of Surfactants in Methanol–Water Mixtures
Authors: Kaneshina Shoji , Manabe Masahiro , Sugihara Gohsuke , Tanaka Mitsuru 
Published: July 2006

Abstract
The partial molal volumes of surfactants in the micellar state (\barVm) and in the singly dispersed state (\barVs) have been determined at 25 °C in methanol-water mixtures up to the composition of 25 mol% methanol. The \barVm of sodium dodecyl sulfate (SDS) increases gradually with the addition of methanol across the plateau region (3–15 mol% methanol). On the other hand, the \barVs values of SDS and its homologous salts containing the alkyl chain of carbon numbers from 6 to 10 decrease initially with the addition of methanol and then increase up to 25 mol% methanol via the minimum at 3 mol% methanol. The value of \barVm–\barVs reaches its maximum at 3 mol% methanol and then approaches zero at about 30 mol% methanol. The latter behavior is an indication of the lack of any micelle formation. In order to elucidate the solute-solvent interactions, the split of \barVs into the contributions of the ionic and the hydrophobic part was attempted. Consequently, the variation in \barVs with the solvent composition can primarily be attributed to the behavior of the hydrophobic group in solutions. On the basis of these results, the interactions between the hydrophobic part of the solute and the binary solvent were discussed.
Electronic Structure and Spectra of Acrylic Acid in the Vapor and Condensed Phases
Authors: Morita Hiroshi , Fuke Kiyokazu , Nagakura Saburo 
Published: July 2006

Abstract
Near and vacuum UV absorption spectra of acrylic acid were measured at room temperature in the vapor phase and at 77 K in the condensed phase. From a comparative study of the observed spectra, a Rydberg excitation band was observed at 7.46 eV in addition to valence-shell transition bands. The estimated value of the quantum defect (δ=1.01) indicates that the Rydberg orbital is 3s. A new modified CNDO-CI method applicable to planar molecules was developed and applied to acrylic acid to investigate the valence-shell transitions, the observed bands at ∼5.0 and 6.71 eV being assigned to the transitions to the n-π* and π-π*, respectively.
Palladium-catalyzed Reaction of Olefins and Acetylenes with Iodoferrocenes
Authors: Kasahara Akira , Izumi Taeko , Maemura Mitsugi 
Published: July 2006

Abstract
Iodoferrocene (1) reacts readily with olefinic compounds in the presence of a catalytic amount of palladium(II) acetate to produce alkenylferrocene derivatives. In the presence of a copper(I) iodide and palladium complex, 1 also reacts with acetylene to afford diferrocenylacetylene.
The Hindered Internal Rotation of Amide Groups of Polyacrylamide of Low Molecular Weights
Authors: Hirai Yoshiyuki , Yukawa Mitsuyoshi , Imamura Yoshio 
Published: July 2006

Abstract
Polyacrylamides of low molecular weights (average degrees of polymerization(‾DP) : 7.2, 18.3, 21.3, and 45.4) were prepared by radical polymerization, and their PMR spectra were observed over the temperature range of 30–90 °C. From the temperature dependence of the PMR spectra, the values of the energy barrier to the internal rotation about C–N bonds were determined by means of a total line-shape analysis. The energy barriers for the polymers above ‾DP : 18.3 were 10.6 kcal/mol, while those for the polymer of ‾DP : 7.2 were 9.2 kcal/mol. These results were interpreted in terms of the local environment around the amide groups. The intramolecular hydrogen bonding was also investigated.
Pyrolysis of Acetylene behind Shock Waves
Authors: Ogura Hiroo 
Published: July 2006

Abstract
The pyrolysis of acetylene was investigated behind the reflected shock waves in a single-pulse shock tube over the temperature range from 1000 to 1670 K. The major products were 1-buten-3-yne, 1,3-butadiyne, and hydrogen. The main primary C4 product, however, changes from 1-buten-3-yne to 1,3-butadiyne with the increase of temperature. At the lower temperatures the formation of 1-buten-3-yne dominates the pyrolysis of acetylene. The rate of 1-buten-3-yne formation is second order with respect to acetylene concentration, and its second-order rate constant is expressed as follows:
k(cm^3 mol^-1s^-1)=10^14.39±0.26exp((-46400±1400)/RT)
The isotopic distribution of 1-buten-3-yne in the pyrolysis of the equimolar C2H2 and C2D2 mixture, proved that the pyrolysis proceeds via a free-radical mechanism. A free-radical chain mechanism initiated by the bimolecular reaction of acetylene, 2C2H2→C4H3+H, was proposed.
The Formation of Amino Acids and Related Oligomers from Formaldehyde and Hydroxylamine in Modified Sea Mediums Related to Prebiotic Conditions
Authors: Hatanaka Hiroshi , Egami Fujio 
Published: July 2006

Abstract
Amino acids and related oligomers were produced from formaldehyde and hydroxylamine in modified sea mediums at pH 5.5 and 105 °C. The modified sea mediums are characterized by a lower concentration of sodium chloride and a higher concentration of essential transition metal ions (Zn2+, Mo6+ as MoO42−, Fe3+, Cu2+, Co2+, and Mn2+) than in sea water; generally small amounts of clays (kaolin and montmorillonite) were added. About 40 species of amino acids were detected in the automatic amino acid analyzer, and 20 of them were tentatively assigned. Glycine, alanine, and serine among the protein amino acids and β-alanine were further confirmed by thin-layer chromatography. Oligomers with molecular weights of about 200–1000 were produced which gave rise to an amino acid mixture by acid hydrolysis. From the ratio (maximum, about 5) of the content of the amino groups after to before hydrolysis and the molecular size, the oligomers were tentatively regarded as oligopeptides of an unknown nature, resistant to pronase digestion. The large-molecular fraction (M. W. about 700) had a phosphatase-like activity able to hydrolyze p-nitrophenyl phosphate.
The Effect of Axial Ligands on the Reductions of Co(III) Complexes with a Macrocyclic Schiff-base Ligand by Fe(edta)2−
Authors: Kurimura Yoshimi , Saito Hiroshi , Nakajima Ikuko , Fujii Yuki 
Published: July 2006

Abstract
The second-order rate constants for the reduction of cobalt(III) complexes with a macrocylic Schiff-base ligand, Co(dop)L22+ (dop=N,N′-bis(2-hydroxyimino-1-methylpropylidene)-1,3-propanediamine and L=primary amine), by Fe (edta)2− are very sensitive to the nature of the axial ligands. The rate increases with a decreases in the basicity of the axial ligands: the order is methylamine, ethylamine, 2-aminoethanol, toluidine, aniline, and bromoaniline derivatives. It is shown that there is a linear relationship between the logarithmic second-order rate constant and the pKa of the axial primary amine ligand. Among the series of primary amine derivatives, the differences in the free energy of the activation for the reduction can be considered to be mainly dependent upon those in the enthalpy of the activation for the bond stretching of the Co–N (axial ligand) prior to the electron-transfer.
Synthesis and Magnetic Properties of Iron(III) Complexes with Several Quadridentate Schiff Bases
Authors: Nishida Yuzo , Oshio Shuhei , Kida Sigeo 
Published: July 2006

Abstract
New iron(III) complexes containing quadridentate Schiff bases, [Fe(L)AB]n+, were prepared, where H2L represents a quadridentate Schiff base, and A and B, unidentate ligands, such as imidazole, pyridine derivatives, and cyanide ions. The magnetic moments of the complexes are in the range of 1.9–6.0 B.M. at room temperature. Based on the magnetic susceptibilities at various temperatures (90–295 K), these compleses were classified into four types: (1) high-spin (S=5⁄2), (2) low-spin (S=1⁄2), (3) intermediate spin (S=3⁄2), and (4) cross-over complexes, the last of which have a ligand-field strength near the cross-over point of high-spin and low-spin types. From the ESR spectra obtained, the existence of a spin-equilibrium was established for the cross-over complexes.
Spin Trapping of Aryl and Arylcyclohexadienyl Radicals by N-t-Butyl-α-phenylnitrone (N-Benzylidene-t-butylamine Oxide) and α,N-Diphenylnitrone (N-Benzylideneaniline Oxide)
Authors: Kamimori Mariko , Sakuragi Hirochika , Suehiro Tadashi , Tokumaru Katsumi , Yoshida Masayuki 
Published: July 2006

Abstract
Monosubstituted phenyl radicals produce only aryl spin adducts in the reaction with nitrones described in the title, while polyhalo-substituted phenyl radicals add to solvent benzene, in competition with the formation of aryl spin adducts, to give arylcyclohexadienyl radicals, which in turn are trapped by the nitrones giving nitroxides incorporating the solvent benzene (Scheme 3).
Rishitin I. The Isolation and Structure Elucidation
Authors: Masamune Tadashi , Murai Akio , Takasugi Mitsuo , Matsunaga Akira , Katsui Nobukatsu , Sato Norio , Tomiyama Kohei 
Published: July 2006

Abstract
A modification of the isolation procedure and the details of the structure elucidation of rishitin (1) are described.
Solid-state Reactions between CVD–TiO2 and BaCO3
Authors: Suyama Yoko , Kato Akio 
Published: July 2006

Abstract
The solid-state reactions between CVD–TiO2 powders of anatase- and rutile-forms with various particle sizes and BaCO3 were investigated in O2 and CO2. The reactivity of the TiO2 powders and the apparent activation energy for the reaction were independent of the crystal type of TiO2. The reactivity of the TiO2 powders increased remarkably as the particle sizes grew smaller than 0.15 μm. When such fine CVD–TiO2 powders were used, the reaction proceeded to completion at temperatures below 1000 °C in both O2 and CO2 and gave fine BaTiO3 powders. The particles of BaTiO3 produced appeared single-crystalline and kept a shape similar to that of the starting TiO2 particle. The sizes of the BaTiO3 particles were controlled by those of the starting TiO2 and were independent of those of BaCO3.
The Theoretical Estimation of the G-Values for the Ionization and Excitation of Thirty-eight Gaseous Compounds Irradiated by 100 keV Electrons
Authors: Okazaki Kiyoshi , Yamabe Masaki , Sato Shin 
Published: July 2006

Abstract
The G-values for the ionization and excitation of thirty-eight gaseous compounds irradiated by 100 keV electrons have been calculated by combining the binary-encounter-collision theory with the theory of the degradation spectrum, which is based on the continuous-slowing-down approximation (CSDA). The thirty-eight compounds include C2–C6 alkanes, cycloalkanes, C2–C4 olefins, acetylene, 1,3-butadiene, benzene, toluene, phenol, pyrrole, furan, several alcohols, ethers, ketones, acetaldehyde, carbon dioxide, and hydrogen cyanide. Most of the calculated G-values of the electrons were in fair agreement with the experimental values. In the cases of several hydrocarbons, the dissociation from the superexcited state into the neutral fragments was taken into account, since the data for the fragmentation ratios were available. In the case of acetylene, the discrepancy in the G-values of electrons obtained experimentally and theoretically suggests that excited acetylene gives rise to a chemiionization reaction. In order to check the CSDA, the Fowler equation for helium has been calculated and the results compared with those obtained under the CSDA. The discrepancy in the G-values obtained by the two methods did not exceed 7%.
The Benzannelated Annulenones. Syntheses and Properties of 10-Methylbenzo[d]- and Dibenzo[d,j]-6,8-bisdehydro[13]annuIenone
Authors: Ojima J\={u}ro , Yokoyama Y\={o}ji , Enkaku Michiko 
Published: July 2006

Abstract
In order to examine the paratropic nature expected for a thirteen-membered ring system arising from polarization of the carbonyl group, the two benzannelated bisdehydro[13] annulenones, VI and IX, were prepared respectively by the aldol condensation of an appropriate aldehyde and an appropriate ketone followed by the oxidative coupling of the resulting acyclic ketone containing terminal acetylene groups. The NMR spectra indicate that both of VI and IX, as well as the respective protonated species, VII and X, are paratropic and paratropicities decrease in the sequence of VI&gt;IX with the increasing number of fused benzene ring. The dibenzannelated annulenone (IX) and its precursor (VIII) were converted into the corresponding alcohols or ethers (XIIa, XIIb and XIa, XIb), respectively, to test the presence of the paratropic nature of IX. The NMR spectra of XIa, XIb and XIIa, XIIb, in addition to those of VIII and IX, suggested that IX seemed to be weakly paratropic. An attempt made to prepare the dibenzannelated bisdehydro[13]annulenyl anion (XIII) was unsuccessful.