bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optically-active Vibrations and Effective Charges of Calcite and Magnesite
Authors: Yamamoto Akio , Shiro Yuji , Murata Hiromu 
Published: July 2006

Abstract
A rigid-ion model analysis was made for the optically-active crystal vibrations of calcite (CaCO3) and magnesite (MgCO3) with reference to the previous vibrational treatments. The effects of the effective charge distribution on the TO–LO splittings of the lattice modes were examined on the proposed distribution model, and the effective charges have been found: Zca=1.21, Zc=0.20, and Zo=−0.47 in calcite, and ZMg=1.28, Zc=0.21, and Zo=−0.50 in magnesite, all in electron units. The force fields and effective charges determined in the present study reproduce satisfactorily the observed transverse and longitudinal frequencies of the optically-active lattice vibrations.
Surface Water Content of Metal Oxides. II. Measurement of Samples Containing Pores: Silica, Alumina and Silica-Alumina
Authors: Naono Hiromitu , Kadota Toshie , Morimoto Tetsuo 
Published: July 2006

Abstract
Two essentially different methods for determining surface water content, i.e., a successive-ignition-loss method and chemical reaction of active hydrogen with methylmagnesium iodide, were applied to the measurement of samples containing pores: silica, alumina, and silica-alumina. It was found that the rate of reaction of methylmagnesium iodide with active hydrogen largely depends upon the pore size distribution. It took 20 min for completion of the reaction on the Aerosil sample having no pores, ca. 1 hr for alumina and silica-alumina which have peaks in the pore size distribution curve at radii 53 and 37 Å, respectively, and 17 hr for porous silica glass and silica gel which have peaks at radii 22 and 19 Å, respectively. The results obtained by the two methods were in good agreement with each other irrespective of the existence of pores in the transitional range. It was confirmed that the nature of the sample is decisive for the population of water content on metal oxides.
An ESR study of the Role of CoO and NiO in Al2O3–MoO3–CoO (or NiO) Desulfurization Catalysts
Authors: Ueda Hisashi , Todo Naoyuki 
Published: July 2006

Abstract
The ESR spectra from the catalyst/perylene/purified-benzene system were studied. The surface equilibria, Co3++P\ightleftharpoonsCo2++P+, Ni3++P\ightleftharpoonsNi2++P+, and Mo6++P\ightleftharpoonsMo5++P+, have been established, with the equilibrium constants at 20°C, 3.3×1015, 3.0×1014, and 6.8×109 respectively. In Al2O3–MoO3–CoO, Mo6++Co2+\ightleftharpoonsMo5++Co3+, is attained; the equilibrium constant obtained was 2.0×10−6, and the corresponding value for Mo6++Ni2+\ightleftharpoonsMo5++Ni3+ was 2.3×10−5. These results indicate that the roles of NiO and CoO in these catalysts are essentially the same. It has been found that the supporting order was important when CoO and MoO3were supported together, but unimportant when NiO and MoO3 were supported together. Considering the known fact that CoO is a more efficient Co-catalyst of MoO3 than NiO at lower supported concentrations (less than 2%), it has been concluded that CoO is incorporated in the alumina-carrier surface less stereospecifically, but more effectively, than NiO.
Reaction of 2-Halo-1-Olefin-1-Carboxylic Acid with Cu2O and Isonitrile
Authors: Ito Yoshihiko , Konoike Toshiro , Fujii Syotaro , Setsune Junichiro , Saegusa Takeo 
Published: July 2006

Abstract
A reaction of 2-halo-1-olefin-1-carboxylic acids with isonitrile and Cu2O is described. o-Chlorobenzoic acid is treated with ter-butyl isocyanide and Cu2O at 80°C to produce benzoic acid (1a), phthalic anhydride (2a), N-tert-butylphthalisoimide (3a) and N-tert-butylphthalimide (4a) in 5, 14, 18, and 32% yields, respectively. With 2-chloro-1-cyclohexene-1-carboxylic acid, a similar result is observed. However, the reaction of acyclic 2-chloro-1-olefin-1-carboxylic acid such as β-chlorocrotonic acid with isonitrile and Cu2O does not give any products corresponding to 1—4. These reactions are interestingly compared with the reaction of o-iodobenzoic acid and copper-(I) acetylide producing 3-alkylidenephthalide. A reaction mechanism involving a transient intermediate of α,β-unsaturated β-lctone (11) is proposed for the present reaction.
Studies of the Catalytic Properties of Synthetic Zeolite A. IV. The Thermal Stability of Silver-exchanged Zeolite A
Authors: Matsumoto Shigemi , Nitta Masahiro , Ogawa Kiyoshi , Aomura Kazuo 
Published: July 2006

Abstract
The effects of the degree of exchange and the dehydration upon the structural stability of silver-exchanged forms of the synthetic zeolite Linde 4A have been investigated by means of DTA, X-ray diffraction, and adsorption studies. The relative intensity of the X-ray powder diffraction decreased with an increase in the extent of Ag+-exchange, though it indicated no accurate information on the crystallinity. An exotherm on the DTA curves which shifted to a lower temperature with the degree of exchange became an indication of the collapse of the structure; this was in good agreement with the specific surface area of the sample heated at a higher temperature. From these results, the silver-exchanged zeolite A was concluded to be thermally unstable and to lose its crystal structure at a lower temperature than the original sodium form. It is also proposed that the comparison of the X-ray powder diffraction intensity is not suitable as a method for judging the crystallinity of zeolites A.
Conformations of Sequential Polypeptides of l-Leucine and Glycine in Solution
Authors: Iio Takayoshi , Takahashi Sho 
Published: July 2006

Abstract
With the aid of optical rotatory dispersion, circular dichroism, and infrared spectra, the conformations of the sequential polypeptides of l-leucine and glycine, (Leu3Gly)n, (Leu2Gly)n, (LeuGly)n, and (LeuGly2)n, were studied and compared with the conformation of poly-l-leucine. It was shown that the polymers (Leu)n, (Leu3Gly)n, (Leu2Gly)n, and (LeuGly)n could be α-helical in solution, but (LeuGly2)n was not. The order of the stability of the α-helix of these polymers was found to be: (Leu)n&gt;(Leu3Gly)n∼(Leu2Gly)n&gt;(LeuGly)n&gt;(LeuGly2)n. This was attributed to interactions between side chains of l-leucines which were regularly arranged on the α-helix.
Liquid-phase Oxidation Catalyzed by Cu(II)–Cl. II. Chloride Ion Transfer during the Oxidation of Cyclohexene
Authors: Imamura Sei-ichiro , Otani Takafumi , Teranishi Hiroshi 
Published: July 2006

Abstract
Cyclohexene was oxidized in glacial acetic acid with a Cu(II)–Cl catalyst. In addition to the main oxidation products, 3-cyclohexenyl chloride, 3-cyclohexenyl acetate, 2-chlorocyclohexanol-(1), cyclohexene oxide, and hydrogen chloride were produced. The mechanism of the formation of these compounds was investigated in detail: the deactivation of the catalyst was explained by chloride ion transfer.
Syntheses and Properties of Crosslinked Ferrocene Polymers
Authors: Omori Mamoru , Kurono Masayasu , Yajima Seishi 
Published: July 2006

Abstract
The polycondensation reaction of acetylferrocene and furfural was investigated in the presence of concentrated H2SO4 as a catalyst without solvent. Stoichiometric reaction took place with 2 mol of acetylferrocene and 5 mol of furfural. Polycondensation afforded satisfactory results when 1 mol of acetylferrocene was treated with 2–7 mol of furfural. The structural evidence for these products was derived from chemical and infrared analyses. Density, micro Vickers hardness, magnetic susceptibility, and thermal behavior of these products were measured in comparison with those of other resins.
Formation of 9,9′:9′,9″-Terfluorenyl Isomers Using Metalated Fluorenes as Synthetic Intermediates
Authors: Minabe Masahiro , Suzuki Kazuo 
Published: July 2006

Abstract
Rotational isomers of 9,9′: 9′,9″-terfluorenyl were obtained by the addition of 9-lithiofluorene to 9,9′-bifluorenylidene (III). 2,7-Dibromo- (VI) and 2,7,2″,7″-tetrabromo-9′,9″-terfluorenyl (VIII) resulted from similar reactions of the corresponding bromo-derivatives. 9-Lithio-9,9′-bifluorenyl was treated with 9-bromo-9,9′-bifluorenyl to give 9,9′-bis(9,9′-bifluorenyl) (X), 9,9′: 9′,9″-terfluorenyl isomers (mp 293 °C (dec) (I) and mp 257 °C (dec) (II)), 9,9′-bifluorenyl (IX), III, and fluorenone. The isomerization of I by metallic potassium gave the other rotamer II, which decomposed into its components, IX, III, and fluorene (IV).
Multifunctional Hydrolytic Catalyses. III. Catalytic Hydrolysis of p-Nitrophenyl Acetate by Imidazole-4-carbohydroxamic Acids
Authors: Kunitake Toyoki , Horie Seiji 
Published: July 2006

Abstract
Imidazole-4-carbohydroxamic acids (I) and its N-methylhydroxamic acid derivative (II) were synthesized from imidazolecarboxylic acid and hydroxylamines, and the catalytic hydrolysis of p-nitrophenyl acetate was studied. The reaction was analyzed by the pseudo-first-order kinetics and the burst kinetics. The hydrolysis proceeds via the formation and the subsequent decomposition of the acetyl hydroxamate intermediate. The acylation rate with these catalysts were comparable to those observed with other simple hydroxamic acids. On the other hand, the deacylation of the acetyl intermediate of II was greater than expected and increased with pH. This suggests that the intramolecular imidazole group (neutral and/or anionic species) assists deacylation, thus increasing the overall efficiency of catalysis.
Photolysis of p-Benzoquinone in Aqueous Solution. Possibility of a Polar Mechanism in the Primary Process
Authors: Shirai Masamitsu , Awatsuji Toshio , Tanaka Makoto 
Published: July 2006

Abstract
The photochemistry of p-benzoquinone in water was investigated spectrophotometrically. The effect of p-nitroso-N,N-dimethylaniline as an additive confirmed a non-radical mechanism. The small positive deuterium isotopic effect suggests an electrophilic attack of the excited p-benzoquinone on water.
Syntheses of Fluorine-Containing Chromans: A Radical Cycloaddition of Phenyl Alkyl Ethers with Hexafluoropropene
Authors: Kimoto Hiroshi , Muramatsu Hiroshige , Inukai Kan 
Published: July 2006

Abstract
Four 2-substituted 4-trifluoromethyl-3,3,4-trifluorochromans were synthesized in one step by the radical cycloaddition of phenyl alkyl ethers and hexafluoropropene in the presence of di-t-butyl peroxide.
A Novel Synthesis of l-Pipecolic Acid
Authors: Fujii Toshiyuki , Miyoshi Muneji 
Published: July 2006

Abstract
A novel synthesis of l-pipecolic acid from l-lysine is described. Bromination of ε-NH2 group on Nα-tosyl-l-lysine, followed by cyclization with NaH in DMF gave N-tosyl-l-pipecolic acid in 45% yield.
A Study on Electronic Spectra of Organic Compounds with S–Cl Group
Authors: Yamabe Tokio , Nagata Shinichi , Kikuzono Yasuo , Fukui Kenichi 
Published: July 2006

Abstract
MO calculations were carried out for CH3SCl, C6H5SCl, and related compounds with the S–Cl group by the CNDO/2 or the ASMO-SCF method. The absorption bands in the 300–400 nm region observed were assigned to the σS-Cl*←nS transition in view of transition energy and oscillator strength. Such characteristic bands are attributed to the extraordinarily low energy level of the σS-Cl* orbital.
Charge-transfer Complexes of Vinyl Polymers with Large Pendant π-electron Systems. I. Poly(N-vinylcarbazole) and Related Compounds
Authors: Okamoto Ken-ichi , Ozeki Miyuki , Itaya Akira , Kusabayashi Shigekazu , Mikawa Hiroshi 
Published: July 2006

Abstract
The absorption spectra and the thermodynamic constants (KCT, ΔH, and ΔS of formation) of the charge-transfer (CT) complexes of poly-N-vinylcarbazole (PVCz), the oligomers of N-vinylcarbazole (VCzOlig I and II, ‾DP=5 and 10 respectively), poly-N-carbazolylethylvinylether (PCzEVE), and the monomeric model compounds were examined in solution in order to clarify the characteristics of the complexes of polymeric donors with large pendant π-electron systems. The apparent spectra were resolved into two CT bands. The complexes of PVCz and VCzOlig II showed a lower frequency shift in the absorption maximum of the first CT band and an increase in the intensity ratio of the first to the second CT bands as compared with those of the monomeric complexes. This behavior, regarded as a kind of so-called polymer effect, seems to arise from some electronic interaction between neighboring carbazolyl groups in one polymer chain; it can be explained by variation both in the electron-donating character and in the distribution of the orientational isomers between the PVCz complexes and the others. A comparison of the observed values of KCT, ΔH, and ΔS among the donors suggested that a dominant factor in determining these values is the steric hindrance rather than the small difference in the electron-donating character in the case of the structurally related polymeric complexes. The steric hindrance is important in the complexes of PCzEVE and VCzOlig I, where the electronic interaction is hardly present.
Simple and Complex Anion-radical Salts Derived from 2,3-Dicyano-1,4-naphthoquinone
Authors: Maki Izumi , Matsunaga Yoshio , Nakakura Mitsuru , Nonaka Akihiko 
Published: July 2006

Abstract
Simple and complex anion-radical salts were prepared by the reduction of 2,3-dicyano-1,4-naphthoquinone with a number of onium iodides. The simple salts are green-colored, and the complex salts, with a composition of 1: 2, are dark green or brown. The latter salts show electronic absorptions extending into the near-infrared region. The electrical resistivities are rather high— 107–1012 ohm cm in the simple salts and 103–107 ohm cm in the complex salts. The ESR spectra characteristic of triplet excitons were observed with polycrystalline samples, and the zero-field splitting parameters and the singlet-triplet separation energies were estimated for most of the salts. The anion-radicals appeared to be in strong pair-by-pair interactions in these salts.
An X-Ray Analysis of the Orientational Disorder of N-Methylphenazinium-TCNQ
Authors: Kobayashi Hayao 
Published: July 2006

Abstract
The X-ray diffraction patterns of NMP-TCNQ show diffuse streaks along the c* direction. The analysis of the intensities of these streaks revealed that the orientation of NMP is one-dimensionally disordered along the c axis. The structure obtained indicates that the potential exerting on an electron moving in a column of TCNQ is not random, but can be expressed by a periodic function; this implies that NMP-TCNQ, can not be regarded as a disordered one-dimensional conductor. The periodicity of the potential means that the one-dimensional energy band must be filled.
Electron Transfer Reaction in the Triplet State. Role of Ferrocene as an Electron Donor
Authors: Kikuchi Koichi , Kokubun Hiroshi , Kikuchi Masae 
Published: July 2006

Abstract
Quenching of the triplet state of methylene blue by ferrocene and p-phenylenediamine in ethanol has been investigated by an emission-absorption flash technique. The triplet dye is quenched by ferrocene and p-phenylenediamine at a diffusion-controlled rate, yielding the semi-reduced dye. Efficiency of the semi-reduced dye formation is 0.09 and 1.0 for ferrocene and p-phenylenediamine, respectively. Since the triplet level of the dye is lower than that of ferrocene, quenching of the triplet dye by ferrocene seems to occur through the charge (electron) transfer interaction.
The Micelle Formation of Mixtures of Polyoxyethylene Type Nonionic Surfactants in Aqueous Solutions
Authors: Nishikido Nagamune , Moroi Yoshikiyo , Matuura Ryohei 
Published: July 2006

Abstract
The critical micelle concentrations (CMC) of mixtures of nonionic surfactants with the same hydrocarbon, i.e. dodecyl group, and with various chain lengths of ethylene oxide, were determined. The observed values were compared with the values calculated by means of the equation derived from the pseudo-phase separation model on the assumption that the mixed micelle is a perfect solution. A good agreement between observed and calculated values was obtained in the mixtures of the surfactants with six or more ethylene-oxide units. However, the observed values of the two-component mixture, one component with five ethylene-oxide units, showed a small deviation from the calculated values. The difference between the above two cases was explained from the viewpoint of the most suitable packing of the first six or fewer ethylene-oxide units near the micelle core in the micelle state.
Basic Properties of Metal Phosphates and Their Catalytic Activity in the Decomposition of Diacetone Alcohol
Authors: Tada Akio 
Published: July 2006

Abstract
The basic properties of alkali and alkaline earth metal phosphates calcined at various temperatures were investigated. The strength of the surface base was determined by the adsorption of acidic indicators from benzene solution. It was found that K3PO4 shows a fairly high basic strength of H0≥17.2. The surface basicity was evaluated by the catalytic activity for the decomposition of diacetone alcohol, which is known to be catalyzed only by basic catalysts. Comparison of the result of the activity measurement with that of TGA indicated that the basicity of a metal phosphate reaches a maximum when dehydrated completely. The nature of the basic sites on metal phosphates is also discussed.
An Electron Spin Resonance Study of the Anion Radicals of Some Nitrotropolonates and 2-Methoxy-5-nitrotropone
Authors: Ikegami Yusaku , Seto Shuichi 
Published: July 2006

Abstract
The anion radicals of 5-nitro-, 3-nitro-, and 3,5-dinitro-tropolonates and of 2-methoxy-5-nitrotropone were generated electrolytically in N,N-dimethylformamide. Hyperfine structures of these ESR spectra were reasonably interpreted with the spin density calculations. The results for the 3-nitro- and 3,5-dinitro-tropolonates suggested that the 3-nitro groups were twisted about 40 and 55°, respectively, from the ring plane.
The Heating-rate Dependence of the Mechanical Properties of Several Polymers at Higher Temperatures
Authors: Furusho Noboru , Komatsu Tsuyoshi , Nakagawa Tsurutaro 
Published: July 2006

Abstract
Measurements of the mechanical properties of various polymers at higher temperatures under the conditions of several heating rates were carried out in the air using the torsional braid analysis (TBA) method. It has become apparent that the examples of the dependence of the mechanical properties upon the heating rate at higher temperatures are classified into two groups. The first is characterized by the fact that the temperature of the maximum in the logarithmic decrement remains unchanged, irrespective of any changes in the heating rate. This situation is related to the physical process. On the other hand, in the case of the second group, the TBA curves are shifted to higher temperatures with an increase in the heating rate; this is the results of chemical processes. A kinetic treatment of thermal analysis, in which kinetic parameters can be calculated from the heating-rate dependence of the characteristic point in the observed curves, was used in the present study. From this analysis, the apparent activation energies of the thermal degradation of polymers were obtained, and comparisons of these values with those from the isothermal measurements were made.
Synthesis and Proton Magnetic Resonance Spectra of Some Dichloro(picolinaldimine)palladium(II) and -platinum(II) Complexes
Authors: Kawakami Katsuhiko , Ohara Takeshi , Matsubayashi Gen-etsu , Tanaka Toshio 
Published: July 2006

Abstract
A series of dichloro(picolinaldimine)palladium(II) and -platinum(II) complexes was prepared. The PMR parameters, the chemical shifts of the ligand protons and the coupling constants between the platinum-195 nucleus and protons attached to carbons adjacent to donor nitrogens of the ligands, are discussed in the light of the metalto-ligand bonds.
The Coprecipitation of Strontium with Hydroxyapatite
Authors: Fujino Osamu 
Published: July 2006

Abstract
The distribution behavior of the strontium ion between hydroxyapatite and the parent solution was investigated. The hydroxyapatite was formed by the extremely slow addition of diammonium hydrogenphosphate to solutions of calcium and strontium nitrate buffered with ethylenediamine at 80 °C. The precipitate yielded a typical X-ray diffraction pattern of hydroxyapatite and had a composition in which the Ca/P molar ratio was 1.67 at pH 6.80. The strontium ion was coprecipitated in the apatite, obeying the Doerner and Hoskins logarithnmic distribution law. The distribution coefficient was scarcely affected by the strontium concentration on the pH value in the parent solution, and had a value of 0.26±0.02 at 80 °C. On the other hand, the apparent distribution coefficient was a little affected by such organic anions as acetate, citrate, lactate, glycinate, and glutamate ions. The lattice constants of the precipitates prepared in the research were measured in order to confirm the formation of the solid solutions.
Chemical Vapor Deposition of Tetraboron Silicide Whiskers
Authors: Motozima Seizi , Sugiyama Kozoh , Takahashi Yasutaka 
Published: July 2006

Abstract
Growth conditions of B4Si whiskers were investigated at the temperature range of 1000–1100 °C. Optimum composition of halides was determined as BCl3/SiCl4=2–0.5, and BCl3=1–6 vol% SiCl4=1–7 vol%. Gold had an excellent impurity effect with optimum concentration of 20–50 μg/cm2 on whisker growth, and gave wool like whiskers of 0.1–1 μm in thickness and 0.5–2 mm in length. B4Si whisker growth was explained in terms of a tip VLS mechanism, for a drop-like deposit of impurity was observed on each tip.
Nuclear Magnetic Resonance Studies of Bicyclic Thiophene Derivatives. I. Ring Current Effects of the Benzene Ring on the Hα and Hβ Signals of the Thiophene Ring in Benzoylthiophene, Thienopyrimidine and Thienodiazepine Derivatives
Authors: Hirohashi Toshiyuki , Inaba Shigeho , Yamamoto Hisao 
Published: July 2006

Abstract
Various thiophene derivatives such as 4-phenyIthienopyrimidines (1), 2-acetylamino-3-benzoylthiophenes (2), 5-phenyl-1,4-thienodiazepines (3) and 5-phenyl-1,4-thienodiazepine-4-oxides (4) have been prepared. Their proton magnetic resonance spectra show that Hα and Hβ of the thiophene ring become more shielded with an increase in bulk of ortho substituent of the benzene ring. This is attributed to the shielding effect of the benzene ring; a steric repulsion between ortho substituent of the benzene ring and some atoms on another moiety of each molecule. Such a repulsion should bring the benzene ring out of the plane of the thiophene ring. The degree of shielding on Hβ by the benzene ring is found to increase in the order 1&lt;2&lt;3&lt;4. This can be taken to indicate that the amount of steric repulsion depends not only on the bulk of ortho substituent of the benzene ring but also on the geometry of each ring system of 1–4.
The Isomerization of the Stable Rotamers of 9,9′: 9′,9″-Terfluorenyls
Authors: Minabe Masahiro , Suzuki Kazuo 
Published: July 2006

Abstract
The conformational change of the s-cis, s-trans-9,9′: 9′,9″-terfluorenyl to the s-cis, s-cis form via the radical process was performed by means of a reaction with N-bromosuccinimide and with various oxidizing agents. A reverse change occurred on treatment with lithium aluminum hydride and with sodium bis(2-methoxyethoxy)aluminum hydride.
The Thermolysis and Photolysis of 6-(Benzylidenehydrazino)uracils. New Syntheses of Pyrazolo[3,4-d]pyrimidines. A Method to Convert Aldehydes to Nitriles
Authors: Yoneda Fumio , Nagamatsu Tomohisa 
Published: July 2006

Abstract
The thermolysis of 6-(benzylidenehydrazino)uracil derivatives generally involves their oxidative cyclization to give the corresponding pyrazolo[3,4-d]pyrimidine derivatives. However, the thermolysis of fully methylated 6-(benzylidenehydrazino)uracils gave no pyrazolo[3,4-d]pyrimidines, but mixtures of the respective nitriles and 1,3-dimethyl-6-methylaminouracil. The photolysis of the fully methylated 6-(benzylidenehydrazino)uracils give the desired pyrazolo[3,4-d]pyrimidines.