bluuebunny/crossref_metadata_2025_split huggingface dataset:
14N Nuclear Quadrupole Relaxation in N-Methylpiperidine
Authors: Negita Hisao , Kubo Tsuneo , Maekawa Michio 
Published: July 2006

Abstract
Two crystal modifications of N-methylpiperidine were found by means of the nuclear quadrupole resonance (NQR) of Nitrogen-14. From the temperature dependence of the 14N spin-lattice relaxation times (T1), it is deduced that the α-form has a lower activation energy for the reorientation of the methyl group than the β-form.
Ceroalbolinic Acid, a Common Body Pigment of Three Ceroplastes Scale Insects in Japan. Confirmation of Structure
Authors: Komura Hajime , Mizukawa Kohsei , Minakata Hiroyuki 
Published: July 2006

Abstract
The structure of ceroalbolinic acid, a widely occurring insect pigment, a common body pigment of three Japanese Ceroplastes scale insects, has been confirmed as 2 by 13C-NMR long-range selective proton decoupling (LSPD) experiments on its permethylated derivative 3. Full assignments of skeletal carbons for 3 were also obtained.
A Simple Synthesis of 7-t-Butyl-4-methyl-2,3-dihydrothiepin
Authors: Yamamoto Kagetoshi , Yamazaki Shoko , Murata Ichiro 
Published: July 2006

Abstract
The novel ring expansion reaction developed for the synthesis of 2,6-di-t-butylthiopyrans has been applied to the short path preparation of a dihydrothiepin derivative. Thus, 4-methyl-6-pivaloyl-3,6-dihydro-2H-thiopyran was converted into 7-t-butyl-4-methyl-2,3-dihydrothiepin in excellent yield by using chlorotrimethylsilane-zinc reagent in tetrahydrofuran.
On the Ratio of Zwitterion Form to Uncharged Form of Glycine at Equilibrium in Various Aqueous Media
Authors: Wada Goro , Tamura Eiko , Okina Mitsuko , Nakamura Mariko 
Published: July 2006

Abstract
The ratios of the zwitterion form to the uncharged form of glycine, KD=[NH3+CH2COO−]/[NH2CH2COOH], were determined in mixtures of water with methanol, ethanol, t-butyl alcohol, dimethyl sulfoxide, acetonitrile, 1,4-dioxane, N,N-dimethylformamide, and tetrahydrofuran. The value of In KD decreases and, therefore, ΔG298° increases, with the increase in the mole fractions of the organic solvents. The plots of ΔG° vs. reciprocal of the dielectric constants of the alcoholic mixtures are simply linear indifferent to the kind of alcohols, indicating that this relation obeys the Scatchard equation and that the free energy change of the process of the intramolecular protonation in glycine is controlled mainly by electrostatic interaction, especially by the entropy change associated with the preferential solvation around the charged amino and carboxyl groups.
Nuclear Quadrupole Resonance of Chlorine-35 in Molybdenum(V) and Rhenium(III) Chlorides. Evidence for the Crystal Modifications of MOCl5
Authors: Kume Yoshio , Nakamura Daiyu 
Published: July 2006

Abstract
The 35Cl NQR frequencies were determined for molybdenum(V) and rhenium(III) chlorides at various temperatures. Two crystal modifications, showing two and three 35Cl NQR frequencies, were found for the former compound. The three resonance frequencies observed for the latter compound are attributable to three chemically different chlorine atoms in the crystal.
Two-photon Excitation Spectra of 1-Azabicyclo[2.2.2]octane and Trimethylamine
Authors: Kuno Hitoshi , Kasatani Kazuo , Kawasaki Masahiro , Sato Hiroyasu 
Published: July 2006

Abstract
The two-photon fluorescence excitation spectra of 1-azabicyclo[2.2.2]octane (ABCO) and trimethylamine were measured in the excitation wavelength range of 410–520 nm. The effect of the polarization (linear or circular) indicates that the symmetries of the upper states are \ ildeA1A1, \ ildeB1A1, and \ ildeC1E for ABCO while \ ildeA1A1 and \ ildeB1E for trimethylamine in C3v point group approximation. Rotational envelopes for the sequence structures are calculated forcircularly and linearly polarized light excitation and are in good agreement with experiment.
Vibration-rotation Spectrum of the Coriolis-interacting Band System ν6 and ν3 of Acetonitrile-d3
Authors: Matsuura Hiroatsu , Murata Hiromu 
Published: July 2006

Abstract
The vibration-rotation infrared spectrum of the Coriolis-interacting band system ν6 and ν3 was measured with a resolution of 0.08 cm−1. The analysis of the spectrum gave values, more precise than before, of the parameters for these bands along with the interaction parameters. A close examination of the observed spectrum revealed a weak Fermi resonance between ν6 and ν4+ν8. The parameters determined, in cm−1, include: (ν0)6 1046.659, α6A 0.01550, α6B−0.000443, (ν0)3 1110.46, α3A−0.0078, and α3B 0.00092, where α6B of and α3B af do not involve the contribution of the Coriolis interaction between ν6 and ν3.
The Phase Relation of the Titanium–Sulfur System
Authors: Saeki Masanobu , Onoda Mitsuko 
Published: July 2006

Abstract
The phase relation of the titanium–sulfur system was studied in the range from TiS1.38 through TiS1.96 at 900 °C by the use of the thermobalance method under controlled sulfur pressure. It was found that four phases, (a) Ti2S3 (4H) with a short-range ordering of titanium vacancies, (b) the superstructure of Ti2S3 (4H) due to the ordering of titanium vacancies, (c) Ti2S3 (4H), and (d) TiS2 (2H), exist in this composition range. The Ti5S8 phase of the 12R type reported previously was not detected for any composition.
The Extraction-spectrophotometric Determination of Lead with Bismuthiol II
Authors: Watanabe Kunihiro , Imaeda Yoshitaka , Kawagaki Ky\={o}z\={o} 
Published: July 2006

Abstract
The solvent extraction-spectrophotometric determination of lead(II) with bismuthiol II was conducted in the presence of 1,10-phenanthroline(phen). Lead(II) was quantitatively extracted as ternary complexes into the chloroform phase over the pH range of 3.0–7.0. The composition of the extracted ternary complexes were confirmed to be Pb: bismuthiol II: phen= 1 : 2 : 2 or 1 : 2 : 1, depending on the concentration of bismuthiol II added to the aqueous solution. The absorption maximum of the ternary complex (1 : 2 : 2) in chloroform was found to be at 342 nm, with a molar extinction coefficient of 3.5×104 dm3 mol−1 cm−1. Under optimum conditions, the absorbance follows Beer’s law up to 300 μg of lead in 10 ml of chloroform. The coefficient of the variation was 1.3% for 30 μg of lead. Many elements interfered with the determination of lead(II). However, the interfering ions, with the exception of the indium and bismuth ions, were masked with a potassium cyanide solution. The proposed method was then applied to the determination of lead in standard zinc metals. A good agreement was observed between the results obtained by the proposed method and the standard values of the samples.
The Electron-donor Property of Zirconia
Authors: Esumi Kunio , Meguro Kenjiro 
Published: July 2006

Abstract
The electron-donor property of zirconia was investigated by means of the adsorption of TCNQ. The TCNQ anion radicals were formed as a result of electron transfer to adsorbed TCNQ from the zirconia surface. The radical concentration decreased with an increase in the calcining temperatures, reached a minimum value at 700 °C, and then increased. This behavior can be explained by a change in the electron-donor site number and the strength of the electron-donor site.
The Crystal Structure of p-Iodobenzoic Acid Investigated by X-Ray Powder Diffraction
Authors: Takaki Yoshito , Kurisu Arifumi , Nakata Kazuaki 
Published: July 2006

Abstract
The crystal of the title compound is monoclinic with space group P21/a, a=30.36(3), b=6.04(1), c=4.16(1) Å, β=97.4(1)° and Z=4. The crystal structure was solved from X-ray powder diffractometer data by the packing analysis based on an ellipsoid-model and by the pattern-fitting structure refinement. The final R (profile) value was 0.168. This structure is isostructural with that of p-bromobenzoic acid.
Vinyl Polymerization. 411. Experimental Supports for the Concept of Hard and Soft Hydrophobic Areas and Monomers in the So-called Uncatalyzed Polymerization
Authors: Ouchi Tatsuro , Inaba Masaya , Imoto Minoru 
Published: July 2006

Abstract
We have proposed a concept of hard and soft hydrophobic areas (HA) and monomers. In order to verify such a concept, two series of experiments were carried out. Poly(styrene-alt-disodium maleate) (1) and poly(styrene-altsodium methyl maleate) (2) were used as initiating macromolecules for the copolymerizations of styrene/methyl methacrylate (MMA) and acrylonitrile/MMA. When 1 was used, MMA was more easily polymerized than styrene. Inversely, when 2 was used, styrene was more easily polymerized than MMA. Poly(styrene-co-sodium acrylate) (3) substances with various compositions were used as intiators for the copolymerizations. The produced copolymers of MMA and styrene were found to have a larger content of MMA as the mole ratio of acrylate in 3 became higher. Inversely, the produced copolymers of MMA and acrylonitrile had a larger content of acrylonitrile as the mole ratio of acrylate became higher. Those results could be reasonably explained by the concept of hard and soft hydrophobic areas and monomers.
Studies on 2-Aziridinecarboxylic Acid. VII. Formation of Dehydroamino Acid Peptides via Isomerization of Peptides Containing 2-Aziridinecarboxylic Acid by Tertiary Amines
Authors: Nakajima Kiichiro , Oda Hitomi , Okawa Kenji 
Published: July 2006

Abstract
Peptides containing 1-(α-aminoacyl)-2-aziridinecarboxylic acid were isomerized into the corresponding dehydroamino acid peptides by treatment with the tertiary amines, triethylamine or 1,4-diazabicyclo[2.2.2]octane (Dabco). Dehydrohydantoin derivatives were also prepared by treatment of benzyloxycarbonyl-2-aziridinecarboxylic acid derivatives with tertiary amines.
Noriceane (Tetracyclo[5.3.1.02,6.04,9]undecane) and 3,5-Dehydronoriceane (Pentacyclo[5.3.1.02,6.03,5.04,9]undecane)
Authors: Katsushima Takeo , Yamaguchi Ryohei , Kawanisi Mituyosi 
Published: July 2006

Abstract
Heating a mixture endo, exo- and endo, endo-2,4-dibromohomoadamantanes at 180 °C in hexamethylphosphoric triamide (HMPT) brings about a novel skeletal rearrangement with concomitant dehydrobromination to give tricyclo[5.3.1.04,9]undeca-2,5-diene (5) in 88% yield. Direct photoexcitation of 5 in diethyl ether induces an intramolecular [2+2] cycloaddition to produce 3,5-dehydronoriceane (2). The bicyclo[2.1.0]pentane moiety constrained in the cage structure of 2 shows almost the same 13C–H coupling constants as those of bicyclo[2.1.0]pentane itself. Finally hydrogenation of 2 over PtO2 easily proceeds to afford noriceane, which is named after the structure of iceane.
The Evaluation of the Association Degree of Sodium Counterinos by Complexes between Sodium Dodecyl Sulfate and Bovine Serum Albumin, Mainly on the Basis of a Conductivity Measurement
Authors: Takeda Kunio 
Published: July 2006

Abstract
Bovine serum albumin was titrated conductometrically with sodium dodecyl sulfate (SDS). Plots of the specific conductance versus the SDS concentration revealed four inflections. The association degrees of sodium counterions by the complexes were evaluated from the changes in the increment of the specific conductance of SDS with the complex growth.
Application of Coagulated Ion-exchanger Colorimetry to the Determination of Trace Amounts of Phosphate in Water
Authors: Matsuhisa Kiichi , Ohzeki Kunio , Kambara Tomihito 
Published: July 2006

Abstract
The combined use of finely divided anion and cation exchange resins reported previously was partly modified and applied to the determination of trace amounts of phosphate in some environmental water samples, such as rain, snow, lake water and seawater. Both orthophosphate and total phosphate were determined and satisfactory results were obtained.
Hydrogen Peroxide-catalyzed Ozonation of Refractory Organics. I. Hydroxyl Radical Formation
Authors: Namba Keisuke , Nakayama Shigeki 
Published: July 2006

Abstract
The kinetics of hydrogen peroxidecatalyzed ozonation was studied in aqueous solutions of various lower alcohols containing ethanol as a reference. The relative rates of degradation of alcohols obtained support the initiation of the reaction by hydroxyl radicals formed in the reaction between ozone and hydrogen peroxide.
The structure of the Cyclodextrin Complex. XIV. Crystal Structure of Hexakis(2,3,6-tri-O-methyl)-α-cyclodextrin–Benzaldehyde (1 : 1) Complex
Authors: Harata Kazuaki , Uekama Kaneto , Otagiri Masaki , Hirayama Fumitoshi , Sugiyama Yukio 
Published: July 2006

Abstract
The crystal structure of the hexakis(2,3,6-tri-O-methyl)-α-cyclodextrin (abbreviated to methyl-α-CDx)–benzaldehyde (1:1) complex, C54H96O30·C7H6O, was investigated by the X-ray method. The crystal is monoclinic with the space group P21 and Z=2; the cell dimensions are a=11.604(1), b=23.832(3), c=13.539(1) Å, and β=106.11(1)°. The structure was determined by inspection of a Patterson map and a trial-and-error method combined with the rigid-body least-squares technique, and refined by the block-diagonal least-squares method to the final R-value of 0.10 for 3597 reflections (sinθ⁄λ≤0.49). The methyl-α-CDx molecule is in the shape of a distorted and truncated hexagonal cone. The guest benzaldehyde molecule is fully included within the host cavity. The carbonyl group is located at the center of the cavity, while the phenyl group is located at the baseside of the host cone. Methyl-α-CDx molecules, of which pseudo hexagonal axis is inclined by an angle of 17.0° against the crystallographic a axis, are stacked along the a axis to form a head-to-tail channel-type structure.
A Kinetic Study of Poly(acrylic acid)–Copper(II) Interactions in Aqueous Solutions
Authors: Yamada Ryuichi , Tamura Kiyoshi , Harada Shoji , Yasunaga Tatsuya 
Published: July 2006

Abstract
Concentration-jump kinetic studies of the aqueous poly(acrylic acid)–copper(II) system reveal the presence of a relaxation phenomenon in the time range of 102 ms. Kinetic data under various pH’s and compositions, together with the potentiometric results, indicate that this relaxation effect is due to the following complex-formation reaction:
CuL2+L22−\oversetk2\undersetk−2\ightleftharpoonsCu(L2)22−,
where L22− is a coordination unit consisting of two adjacent carboxylato side groups on the polymer chain. The specific features of the pH dependence of the τ−1 value are discussed in relation to the degree of dissociation of the carboxyl groups. The rate and stability constants of the reaction are determined to be: k2=5.6×103 M−1 s−1 (1 M=1 mol dm−3), k−2=0.7 s−1, and K2 (=k2⁄k−2)=7.9×103, at pH 7.0, I≈0, and 25 °C. The overall complex-formation mechanism, involving the very rapid formation of CuL2, is discussed.
Electronic Structure of V2(CO)8(μ-PPh2)2 and Mn2(CO)8(μ-AsPh2)2 by Electron Spin Resonance Study of Their Ion Radicals
Authors: Kawamura Takashi , Enoki Sachio , Hayashida Shigeru , Yonezawa Teijiro 
Published: July 2006

Abstract
The anion radical of V2(CO)8(μ-PPh2)2 and the cation radical of Mn2(CO)8(μ-AsPh2)2 are generated by chemical reduction of the vanadium complex with LiBHEt3 or potassium naphthalenide and by radiochemical oxidation of the manganese complex in frozen Freon mixture, respectively. Their anisotropic ESR spectra show that the V2P2 and the Mn2As2 rhomboids are planar. Their g and hyperfine splitting tensors are analyzed on the basis of a qualitative molecular orbital scheme for metal-metal bonds developed from a hypothesis that metal-ligand interactions are larger than metal-metal interactions. The odd electron orbital of V2(CO)8(μ-PPh2)2−· is assigned to the metal-metal π* MO and the odd electron density on the vanadium d AO is estimated as 0.21. The odd electron of Mn2(CO)8(μ-AsPh2)2+· is concluded to be accomodated in the metal-metal σ* MO and odd electron densities on manganese and arsenic atoms are evaluated as ρ(Mn d)=0.25 and ρ(As p)=0.08 or 0.16, respectively. Order of magnitude estimates of orbital energy differences between metal-metal MO’s are obtained from analyses of g tensors as ε(π*)−ε(σ)\simeq0.4 and ε(π*)−ε(δ)\simeq0.9 eV for the anionic divanadium complex and ε(σ*)−ε(δ*)\simeq1.1 and ε(σ*)−ε(π)\simeq1.4 eV for the cationic dimanganese complex.
The Crystal and Molecular Structure of 3-(1,4-Epoxy-2-hydroxy-2,6,6-trimethylcyclohexyl)-1-methyl-2-propyl p-Nitrobenzoate
Authors: Kitano Yukishige , Kato Tetsuya , Kondo Hisao , Ashida Tamaichi 
Published: July 2006

Abstract
The relative configuration of natural 3,6-epoxy-5-hydroxy-5,6-dihydro-β-ionol, C13H22O3, a principal tobacco constituent, has been established by an X-ray crystal structure analysis of its p-nitrobenzoate, C20H25NO6, as (±)-(1R,2R,5S)-2,5-epoxy-2-[(1E,3S)-3-hydroxy-1-butenyl]-1,3,3-trimethyl-1-cyclohexanol. The derivative crystallizes in space group P\bar1 with a=11.618(1), b=12.373(2), c=7.934(1) Å, α=108.43(1), β=108.89(1), γ=95.95(1)° and Z=2. The crystal structure was solved by the direct phasing method and refined by the blockdiagonal least-squares method to the final R index of 0.073 for 2550 reflections. The hydrogen bondings linking the two molecules placed in pairs around a crystallographic center of symmetry are disordered over two sites in the crystal.
Spectrophotometric Determination of Palladium(II) by Extraction of Its 1-Pyrrolidinecarbodithioate into Molten Naphthalene
Authors: Kumar Avadesh , Hussain M F , Satake Masatada , Puri B K 
Published: July 2006

Abstract
A new spectrophotometric method for the determination of palladium after extraction of its 1-pyrrolidinecarbodithioate into molten naphthalene has been developed. Palladium forms a water-insoluble, thermally stable 1:2 complex with 1-pyrrolidinecarbodithioate which is easily extracted into molten naphthalene in the pH range of 3.0–6.0. At room temperature, solid naphthalene containing the metal-complex is dissolved in chloroform (10 ml). It has an absorption maximum in the range of 336–342 nm. Beer’s law holds in the concentration range of 2.5–90.0 μg of palladium in 10 ml of chloroform solution. The molar absorptivity(1 mol−1 cm−1) and sensitivity (μg/cm2) are found to be 6.4×103 and 0.0166, respectively. Samples containing 30 μg of palladium gives a mean absorbance of 0.18 with a standard deviation of 0.0025. Other factors such as amount of reagent and naphthalene, pH, aqueous phase volume and diverse ions have been examined. The method has been applied to the analysis of some alloys.
Selective Determination of Histamine in Urine by Solvent Extraction with Tetrabromophenolphthalein Ethyl Ester and Atomic Absorption Spectrophotometry
Authors: Sakai Tadao , Ohno Noriko , Wakisaka Takashi , Kidani Yoshinori 
Published: July 2006

Abstract
A simple determination method of histamine in urine by solvent extraction and atomic absorption spectrophotometry has been established. The method is based on the formation of histamine–Cu(II) chelate cation, followed by the extraction of ion-associates with tetrabromophenolphthalein ethyl ester into 1,2-dichloroethane. Histamine in urine can be successfully determined without separation and purification from other histamine derivatives and amines. A linearity is obtained in the concentration range (0.4–4)×10−5 M (1 M=1 mol dm−3) histamine in aqueous solutions. The relative deviation is ca. 1.8%.
Spectrophotometric Determination of Silicic Acid by Flow Injection Analysis
Authors: Yokoyama Takushi , Hirai Yukio , Yoza Norimasa , Tarutani Toshikazu , Ohashi Shigeru 
Published: July 2006

Abstract
Flow injection analysis (FIA) was developed for the spectrophotometric determination of silicic acid based on the formation of a yellow molybdosilicic acid (yellow method) and a heteropoly blue complex (blue method). In the yellow method, silicic acid in the concentration range of 2 to 100 ppm (SiO2) could be determined at a sampling rate of 60 samples/h. The FIA system was modified to determine silicic acid in the presence of orthophosphate. Oxalic acid was used for the decomposition of molybdophosphoric acid. The modified system was employed for the rapid and selective determination of silicic acid in well and river waters. In the blue method, ascorbic acid was used to reduce the yellow molybdosilicic acid to a heteropoly blue complex. Silicic acid in the concentration range of 0.02 to 1.0 ppm (SiO2) could be determined at a sampling rate of 40 samples/h. The FIA system was also modified to determine silicic acid in the presence of orthophosphate. The reducing agent was introduced after molybdophosphoric acid had been completely decomposed by adding oxalic acid. The modified system was employed for the determination of silicic acid in sea water.
Mössbauer Emission Spectroscopic Study of Some Spin Crossover Cobalt(II) Complexes
Authors: Maeda Yonezo , Ohshio Hiroki , Takashima Yoshimasa 
Published: July 2006

Abstract
The Mössbauer emission spectra of [57Co(terpy)2]X2 (X=Cl and ClO4), [57Co(snn)2](ClO4)2, and [57Co(snnme)2](ClO4)2 (terpy=2,2′ : 6′2″-terpyridine, snn=N-(2-pyridylmethylene)-2-(methylthio)aniline, and snnme=N-(6-methyl-2-pyridylmethylene)-2-(methylthio)aniline) were examined. These cobalt complexes show thermally induced spin crossover behavior and the temperature dependence of their magnetic moment varies with the counter anion, although the corresponding iron complexes are in a low-spin state. The high-spin iron(II) species ascribed to a metastable form are observed in the emission spectra of [57Co(terpy)2](ClO4)2·2H2O and [57Co(snnme)2](ClO4)2, and their spectral areas increase with decreasing source temperature. The effective vibrating mass for the iron complex observed in the emission spectra of [57Co(snnme)2](ClO4)2 was calculated from the temperature dependence of the isomer shift value, and was used to distinguish whether the iron complex formed by EC-decay of a cobalt-57 atom is stable or metastable.
Carbon Black as an Electron-transfer Catalyst. The Two-phase Dehydrogenation of Hydrazo Nitriles by an Aqueous Solution of Potassium Hexacyanoferrate(III), Using Carbon Black as the Catalyst
Authors: Tsubokawa Norio , Tareda Naoki , Sone Yasuo 
Published: July 2006

Abstract
The two-phase(aqueous and organic phase) dehydrogenation of hydrazo nitriles by an aqueous solution of potassium hexacyanoferrate(III), using carbon black as the catalyst, was carried out at 40 °C with shaking. In the presence of carbon black, the two-phase dehydrogenation of hydrazo nitriles was accelerated, and the corresponding azo nitriles were obtained in good yields. The catalytic activity of channel blacks was larger than that of furnace blacks. Moreover, the increasing content of phenolic hydroxyl groups tended to increase the catalytic activity of carbon blacks. It became apparent that phenolic hydroxyl groups on the surface of carbon black act as an electron-transfer catalyst in the two-phase dehydrogenation. The reaction scheme was considered to be as follows. In the aqueous phase, phenolic hydroxyl groups on the surface are oxidized by an aqueous solution of K3[Fe(CN)6] to give phenoxyl radicals, and then the carbon black with phenoxyl radicals is transferred into the organic phase, which contains hydrazo nitriles. Subsequently, in the organic phase, the phenoxyl radicals oxidize the hydrazo nitriles to give the corresponding azo nitriles, by which phenolic hydroxyl groups are regenerated. Thus, it was concluded that phenolic hydroxyl groups on the surface are recycled and that carbon black mediates the redox reaction occurring between aqueous and organic phases.