bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improvements of the Empirical π* Solvent Polarity Scale
Authors: Abe Takehiro 
Published: July 2006

Abstract
The famous empirical π* (or π1*(N)) solvent polarity scale has been improved for nonassociating solvents by introducing newly presented solvent polarity parameters of π1* and π2* Here, the π1* parameter is a modified form of the π1*(N) scale. The shortcoming that the π* scale does not correlate to solvent spectral shifts of nonpolar and less polarized solutes has been overcome by introducing the new supplementary π2* solvent scale. The present parameters of π1* and π2*, the physical meanings of which are clarified on the basis of their theoretical background, are more successfully applied to the solvent frequencies of both nonpolar and less polarized solutes and to the logarithmic rate constants for organic reactions than is the π1*(N) scale.
Radiation-Induced Polymerization of Isobutyl Vinyl Ether by Diphenyliodonium Hexafluorophosphate. Contribution of Free Radicals to Cationic Polymerization
Authors: Teramoto Mitsuhito , Yamamoto Yukio , Hayashi Koichiro 
Published: July 2006

Abstract
The radiation-induced cationic polymerization of isobutyl vinyl ether by Ph2IPF6 was investigated in dichloromethane solution. The polymerization occurs in the aerated solution containing the salt and is extremely accelerated when the solution is degassed. Contribution of radiolytically produced radicals to the cationic initiation is described. Results for the polymerization by Ph3SPF6 are also presented for the sake of comparison.
The Determination of a Small Amount of a Biological Constituent by the Use of Chemiluminescence. XVII. Experimental Consideration on the Chemiluminescence Detection of Protein Using the 1,10-Phenanthroline-Hydrogen Peroxide–Copper(II) System
Authors: Hara Tadashi , Tsukagoshi Kazuhiko , Kimoto Hideshi , Imai Toshihito , Nakajima Riichirou 
Published: July 2006

Abstract
With an objective to clarify the relationship between chemiluminescence intensity and the reaction time in the flow injection analysis of a small amount of protein using a 1,10–phenanthroline-hydrogen peroxide–copper(II) chemiluminescence system, an apparatus was newly set up for continuously measuring the chemiluminescence intensity. With this apparatus a lowering of the catalytic activity of copper(II) was observed in the presence of α-amino acids, polyamines, polypeptides, and proteins. In addition, the effect of heating on the reaction between copper(II) and protein was examined, and the reaction rate was found to markedly increase. Heating was therefore indispensable for the rapid and sensitive detection of proteins.
Type II Photoreaction of 2-Benzoylcycloalkanones: Conformational Control in the Biradical Formation and in the Behavior of Biradicals
Authors: Hasegawa Tadashi , Hojo Fusao , Yoshioka Michikazu 
Published: July 2006

Abstract
The photoreactivities of 2-benzoylcycloalkanones were shown to be controlled by their ring conformation; 2-benzoylcycloalkanones underwent the Type II elimination and/or cyclization, and/or the α-cleavage reaction.
An Efficient Synthesis of 5,7-Dihydroxy-4-methylisobenzofuran-1(3N)-one, a Metabolite of aspergillus flavus and a Key Intermediate in the Synthesis of Mycophenolic Acid
Authors: Kobayashi Kazuhiro , Shimizu Hideki , Itoh Masahito , Suginome Hiroshi 
Published: July 2006

Abstract
An efficient new synthesis of 5,7-dihydroxy-4-methylisobenzofuran-1(3H)-one, a metabolite of aspergillus flavus and a key intermediate in the synthesis of mycophenolic acid, is reported. The new synthesis involves the preparation of 1,2-dihydro-4,6-dimethoxy-3-methylbenzocyclobuten-1-ol and a regioselective β-scission of alkoxyl radical generated from it with lead tetraacetate as the key steps.
Stereochemistry of Thermal Chlorine-for-Bromine Substitution in Diastereomeric 3-Bromo-4-fluorohexane
Authors: Sharma Ram B , Meyer Richard J , Rack Edward P 
Published: July 2006

Abstract
The stereochemistry of thermalized chlorine-for-bromine substitution was studied in gaseous (3RS,4SR)- and (3RS,4RS)-3-bromo-4-fluorohexane. While energetic chlorine-for-bromine substitution occurs by a two-channel substitution mechanism, one leading to retention, the other to inversion of configuration, thermal chlorine-for-bromine substitution at the sp3-hybridized carbon of the diastereomers proceeds extensively, if not exclusively, via stereochemical inversion.
On the Volume Flow in Nonequilibrium Membrane Systems
Authors: Garrido Javier , Compañ Vicente 
Published: July 2006

Abstract
The volume flow definitions of the different formulations which describe irreversible proccesses in isothermal membrane systems are critically analysed. We show that only one of these definitions can be considered as the volume change observed in each compartment. The study carried out considers the general case of multicomponent systems with arbitrary dissociation degrees.
Transportation of Monosaccharides by Electrodialysis with Ion-Exchange Membranes. I
Authors: Shigemasa Yoshihiro , Yamasaki Osamu , Sashiwa Hitoshi , Saimoto Hiroyuki 
Published: July 2006

Abstract
The effects of voltage, electrolytes, monosaccharides, and pH on the transportation of monosaccharides by electrodialysis were investigated. Transportation was strongly affected by the formation of monosaccharide-borate esters. It was possible to separate saccharides using an electrodialysis technique.
Rotational Effect on Radiationless Transition I: Fluorescence Depolarization in Pyrimidine
Authors: Kanamaru Nobuaki 
Published: July 2006

Abstract
Fluorescence depolarization after R branch excitation of 000 1B1 pyrimidine was interpreted by utilizing ΔJ=0 and/or ±1 coupling schemes within a singlet manifold through triplet rovibronic levels where spin-orbit, vibration-rotation, and hyperfine interaction terms are involved. These schemes are suggested to be useful interpreting the intermediate-case phenomena observed in this kind of molecules.
Photophysics on Solid Surfaces. Time-Resolved Fluorescence Spectra of Pyrene Adsorbed on Calcinated Vycor Glass
Authors: Fujii Tsuneo , Ishii Akira , Satozono Hiroshi , Suzuki Satoshi , Che Michel , Anpo Masakazu 
Published: July 2006

Abstract
The fluorescence, fluorescence excitation, and time-resolved fluorescence spectra of pyrene molecules adsorbed on calcinated (773 K) Vycor glass (average pore diameter, 40 Å) have been investigated as a function of the amount of adsorbed pyrene. The results of the analyses of these spectra and multi-component decays of fluorescence suggest that there are three fluorescent species with different decay times on the surface of Vycor glass. Their lifetimes are determined to be 303–355, 100–145, and 19–48 ns. These decay components are reasonably assigned to the emissions of monomeric, dimeric, and excimer-like species in the order of decreasing the lifetimes. A 26600 cm−1 peak appearing at the first stage of the time-resolved fluorescence spectra is assingned to the 0–0 hand of dimeric pyrene based on the results reported by Yamazaki et al. in the Langmuir-Blodgett monolayer.
Crystal and Molecular Structure of the Crystalline Host-Guest Complex between (R)-(+)-2,2′-Dihydroxy-1,1′-binaphthyl and (S)-(−)-(Ethyl m-Tolyl Selenoxide)
Authors: Fujiwara Takaji , Tanaka Naoki , Ooshita Ryuzou , Hino Ryoji , Mori Koji , Toda Fumio 
Published: July 2006

Abstract
The crystal and molecular structure of the title complex was determined by X-ray method. The absolute configuration of the host (+)-2,2′-dihydroxy-1,1′-binaphthyl (1) was determined to be R and the guest (−)-(ethyl m-tolyl selenoxide) (2) to be S. Two Se–C and one S-O bond lengths are 1.926(7), 1.970(8), and 1.677(5) Å, respectively, and the arrangement around Se atom is roughly tetrahedral. There are O(guest)···HO(host)OH···O(guest) hydrogen bonds between the host and the guest molecules.
Electron Paramagnetic Resonance Study of the Dimer Formation of Bis(acetylacetonato)oxovanadium(IV)
Authors: Kawata Satoshi , Yokoi Hiroshi , Iwaizumi Masamoto 
Published: July 2006

Abstract
Dimer formation of the title complex in toluene and benzene mixed solvents has been demonstrated by the EPR spectroscopy. The dimer structure and the spin-exchange energy have been examined by spectral simulation for ΔMs=2 transitions and the temperature dependence of their spectral intensities, respectively. It has been found that the structure and the magnetism are similar to those of the inversion pair of bis(benzoylacetonato)oxovanadium(IV) in a crystal which is known to show dimeric interactions in its EPR spectra. The formation constant of the dimer, K, for 2 [monomer] \ightleftharpoons dimer has been determined by analyzing the concentration dependence of the dimer and the monomer EPR signals, indicating that K is remarkably solvent-dependent.
ESR Studies at High Pressure. II. Spin Exchange of 2,2,6,6-Tetramethyl-4-oxo-1-piperidinyloxyl in Protic and Aprotic Solvents
Authors: Sueishi Yoshimi , Nishimura Norio , Hirata Koichi , Kuwata Keiji 
Published: July 2006

Abstract
The activation volumes for the spin exchange of 2,2,6,6-tetramethyl-4-oxo-1-piperidinyloxyl (Tanone) in protic and aprotic solvents were determined from the pressure dependence of the rate constants, and were compared with those for the diffusive process. It was concluded that the rate process for the spin exchange in aprotic solvents is a diffusion-controlled one, and in protic solvents an encounter complex as intermediate is formed. The average reaction volume for the complex formation in protic solvents was estimated to be −3.6 cm3 mol−1.
Homoconjugated Diene as a Dienophile to Troponoid Compounds: The Stereoselective Addition Reactions of Tropone and 8,8-Dicyanoheptafulvene with Tricyclo[3.2.2.02,4]nona-6,8-diene Derivative and Thermal and Photochemical Isomerizations of the Adducts
Authors: Ito Kazuaki , Noro Yukie , Saito Katsuhiro , Takahashi Kensuke 
Published: July 2006

Abstract
Thermal addition reactions of tropone and 8,8-dicyanoheptafulvene with a homoconjugated diene, dimethyl 3-cyanotricyclo[3.2.2.02,4]nona-6,8-diene-6,7-dicarboxylate derivative, proceeded stereoselectively to give endo-[4+2]-type cycloadducts, where the troponoids acted as 4 π components. Upon photo-irradiation the adducts afforded intramolecular [2+2]-type addition products to verify the endo-form of the adducts. Molecular orbital caluculations suggested that the stereoselectivity could be explained by secondary orbital interactions between the HOMO of the troponoid compounds and the LUMO of the tricyclic compound. A thermal reaction of the adducts gave three-membered ring opened products, which further proceeded through an intramolecular [2+2]-type reaction upon photo-irradiation.
Diphenylsilane Reduction of C=O and C=N Bearing Electron-Withdrawing Group in the Presence of Aluminum(III) Chloride
Authors: Hojo Makoto , Hojo Masahiro , Inoue Yoshihiko , Tanimoto Shigeo 
Published: July 2006

Abstract
Several α-keto esters and methyl N-p-tolylsulfonyl-2-aryl-2-iminoacetates were reduced to the corresponding α-hydroxy esters and methyl N-p-tolylsulfonyl-2-arylglycinates in high yields by a combination of aluminum(III) chloride and diphenylsilane under operating conditions in which diphenylsilane was added to the pre-formed substrate-aluminum(III) chloride complex in dichloromethane and the mixture stirred. The case of an exactly equivalent amount of aluminum(III) chloride as the substrate resulted in good results.
Preparation of Fluoroamminecobalt(III) Complexes
Authors: Mitsutsuka Yoshihiro , Tursun Erkin , Nakahara Masayoshi 
Published: July 2006

Abstract
New preparation methods are reported for some fluoroamminecobalt(III) complexes. The polarized spectra were measured by microspectrophotometry for some complexes. Coordination geometries of the complexes were predicted from the spectral data.
Effect of Solvent on the Electrochemical Properties of Chromotropic Copper(II) Mixed Chelates
Authors: Labuda Jan , Mafune Kumiko , Fukuda Yutaka 
Published: July 2006

Abstract
Electrochemical and electronic spectral bahaviors of complexes [Cu(acac)(tmen)]ClO4 and [Cu2(taet)(tmen)2](ClO4)2, where acac=acetylacetonate ion, tmen=N,N,N′,N′-tetramethylethylenediamine, taet=1,1,2,2-tetraacetylethanediide ion, were investigated in six solvents by cyclic voltammetry, constant potential coulometry, and visible absorption spectroscopy. Copper(II) undergoes electrolytic reduction to copper(I) coupled with the complex decomposition. The values of reduction potential vs. \ ildeν max of the d-d absorption band show linear correlation in accordance with coordination ability of the solvent.
Voltammetric Investigation of the Response Mechanism of the Ion-Selective Electrodes Based on the Polymer Modified with Poly(oxyethylene) Derivatives in Acetonitrile
Authors: Nakamura Toshio , Nakamura Yasuyuki , Kojima Teruhito , Izutsu Kosuke 
Published: July 2006

Abstract
The voltammetric behavior of barium and lithium ions in acetonitrile (AN) was studied at polymer membrane ion-selective electrodes which showed Nernstian responses to those metal ions in AN, in order to elucidate the mechanism of their potentiometric responses. The membrane electrodes consisted of polyacrylamide coupled to such poly(oxyethylene) derivatives as tetraethylene glycol monododecyl ether, dibenzo-18-crown-6, and cryptand222B and coated on platinum or gold disk. The cyclic voltammograms for barium and lithium ions, recorded repeatedly after setting the electrodes at the rest potentials, showed a cathodic peak at −1.5±0.2 V vs. Ag/0.01 M Ag+ (AN). The cathodic peak current (icp) decreased markedly between the first and second scans, but reached a steady value after the third scan. The icp values after the third scan were diffusion controlled and considered to be due to a transfer of the metal ions from the solution into the membrane. The differences in icp between the first and the third scans were proportional to the potential scan rate and attributed to a transfer of the metal ions which had been accumulated at or near the surface of the membrane by combining with the functional groups of the polymer. The accumulation occurred rather slowly and saturated with time. Based on the fact that the response processes of the ion-selective electrodes were very much similar to the accumulation processes, the response mechanism of the ion-selective electrodes is discussed.
Preparation and Characterization of Optically Active Schiff Base-Oxovanadium(IV) and -Oxovanadium(V) Complexes and Catalytic Properties of These Complexes on Asymmetric Oxidation of Sulfides into Sulfoxides with Organic Hydroperoxides
Authors: Nakajima Kiyohiko , Kojima Katsuhide , Kojima Masaaki , Fujita Junnosuke 
Published: July 2006

Abstract
Oxovanadium(V) complexes, VVO (Schiff base)Y (Y=ClO4, Cl, NO3), with quadridentate Schiff base ligands derived from optically active 1,2-diamines and salicylaldehyde or its derivatives were prepared by oxidizing the corresponding VIVO (Schiff base) with CeIV in acetonitrile followed by the addition of HY. The complexes were characterized by their 1H NMR, IR, UV-Vis, and circular dichroism spectra, and electrochemistry. Reversible reduction potentials (V5+/V4+) obtained by cyclic voltammetry for a series of oxovanadium(V) complexes with Schiff base ligands derived from 5-substituted salicylaldehydes showed a linear dependence on the Hammett parameter. Both the vanadium(IV) and the vanadium(V) complexes catalyze asymmetric oxidation of sulfides into the corresponding sulfoxides with organic hydroperoxides. The oxovanadium(IV) complex catalysts gave much better asymmetric induction than the oxovanadium(V) complex catalysts and in most cases the enantiomeric excess (ee) ranged between 20 and 40%. In the reaction of VIVO (Schiff base) with an organic hydroperoxide the complex is finally converted into the oxovanadium(V) species, and a dark brown intermediate is suggested to be the catalytically active species.
Polarographic Study of the Rates of the Dissociation Reactions of the Eu(III)-HAHA Complex and of the Eu(III)-, Gd(III)-, and Ho(III)-PAPA Complexes
Authors: Kodama Mutsuo , Mahatma Anung Budhi , Koike Toru , Kimura Eiichi 
Published: July 2006

Abstract
Polyaza macrocycles carrying acetate groups, HAHA and PAPA, were found to form solely 1:1 ratio complexes with Eu(III), Gd(III), or Ho(III) ions. The PAPA complexes of the Eu(III), Gd(III), and Ho(III) ions and the HAHA complex of the Eu(III) ion in acetate buffer solutions containing an excess of the Eu(III), Gd(III), or Ho(III) ion produce anodic waves, which are kinetic in nature. They can be ascribed to the free macrocycles formed upon the dissociations of the complexes preceding electron-transfer steps at the electrode surface. From an experimental examination of the nature of these kinetic waves, the reaction mechanisms and rates for the dissociation reactions were determined. The dissociation reactions for the HAHA and PAPA complexes were found to proceed through (A) and (B), respectively. The (kd)o values for the Eu(III)-HAHA and -PAPA complexes were 5.1×10−1 and 3.9×10−2 (sec−1), respectively, and those for the Gd(III)- and Ho(III)-PAPA complexes, 4.04×10−2 and 1.2×10−2 (sec−1).
(Remark: Graphics omitted.)
The (kd) values for the Eu(III)-HAHA abd -PAPA complexes were 3.70×102 and 4.24×105 (mol−1dm3s−1) and those for the Gd(III)-and Ho(III)-PAPA complexes, 2.45×104 (mol−1dm3s−1).
The Headspace Gas Chromatographic Study on (Biphenyl, Naphthalene)–(Benzene, Cyclohexane, 1-Octanol) Binary Mixtures at 298.15 K
Authors: Sanemasa Isao 
Published: July 2006

Abstract
The vapor pressure of each constituent of the title binary mixtures, except for 1-octanol, was measured by the headspace gas chromatography as a function of biphenyl or naphthalene mole fraction in a relative scale taking the vapor pressure of the pure component as unity.
Electrochemical Calorimetry of D2O Electrolysis Using a Palladium Cathode—An Undivided, Open Cell System—
Authors: Oyama Noboru , Ohsaka Takeo , Hatozaki Osamu , Kurasawa Yuko , Yamamoto Nobushige , Kasahara Seiji , Ohta Naoki , Imai Yuko , Oyama Yukio , Nakamura Tomoo , Shibata Tokushi , Imamura Mineo , Uwamino Yoshitomo , Shibata Seiichi 
Published: July 2006

Abstract
The electrochemical calorimetry of the electrolysis of D2O has been carried out using a Pd cathode in an undivided, open cell fashion, together with measuring the total volume of the evolved gases. The excess heat production, observed using a Pd cathode pretreated by a special procedure, can not be explained as a result of the D2–O2 recombination alone. However, the present data certainly do not confirm “cold fusion”, because no evidence has yet been obtained for neutron, gamma-ray, tritium or helium production during our electrolysis of D2O with Pd cathodes.
A New Photochromic Spiro[3H-1,4-oxazine]
Authors: Kawauchi Susumu , Yoshida Haruo , Yamashina Naoko , Ohira Manabu , Saeda Shigeru , Irie Masahiro 
Published: July 2006

Abstract
A new photochromic spiro[3H-1,4-oxazine] 4 is described. The absorption spectra of 4 have been examined and compared with those of spiro[indoline-naphthoxazine] 1. The colored form of 4 has the absorption maximum shorter than that of 1. Compound 4 showed excellent light fatigue-resistant property.
Analysis of Two-Year Results of Acid Precipitation Survey within Japan
Authors: Hara Hiroshi , Ito Ei-ichi , Katou Takunori , Kitamura Yoko , Komeiji Tetsuhito , Oohara Mayumi , Okita Toshiichi , Sekiguchi Kyoichi , Taguchi Keisuke , Tamaki Motonori , Yamanaka Yoshio , Yoshimura Kenichiro 
Published: July 2006

Abstract
Precipitation chemistry within Japan has been assessed in order to judge both the magnitudes of the concentrations and the deposition of major ions: H+, NH4+, Ca2+, K+, Mg2+, Na+, SO42, NO3−, and Cl−. A data set was obtained through an acid precipitation survey by Japan Environment Agency at 14 stations from April 1984 to March 1986. The annual average pH at each site ranged from 4.5 to 5.1 with a mean value of 4.7. The free acidity was derived both from sulfuric and nitric acids; sulfuric acid was found to contribute to 67–83% of the free acidity. The acidity was apparently lower than that expected from SO42− and NO3− levels, mainly because alkaline species, such as NH3, and Ca2+ species neutralized a certain fraction of the original acidity. This neutralization would certify the fact that SO42− and NO3− deposition were comparable to, or smaller than those in eastern North America, but the Ca2+ and NH4+ deposition within Japan exceeded that within the U. S.
Ultrasonic Absorption Studies of the Micellar Catalyzed Reaction of the Base Dissociation of Ammonia
Authors: Harada Shoji , Doi Teruhiko , Sano Takayuki , Yamashita (Isoda) Teruyo , Yano Hiroshige 
Published: July 2006

Abstract
The base dissociation of ammonia has been studied by an ultrasonic absorption method in both the absence and presence of SDS micelle in aqueous solution, and kinetic parameters were obtained. The micellar catalyzed reaction mechanism, including the interactions of ammonium ion with SDS micelles, are discussed.
Reactions of Ozone with 1-Methylcyclohexene and Methylenecyclohexane in Air
Authors: Hatakeyama Shiro , Akimoto Hajime 
Published: July 2006

Abstract
Reactions of ozone with 1-methylcyclohexene and methylenecyclohexane were studied for the purpose of obtaining the reaction mechanism as a prototype of the reaction of ozone with pinenes. The similarity of the yields of corresponding gaseous products between 1-methylcyclohexene and α-pinene and between methylenecyclohexane and β-pinene indicates the similarity of the reaction mechanisms.
Excited Triplet States of Dimethyl Ether Studied by Electron Energy-Loss Spectroscopy
Authors: Ogawa Teiichiro , Yoshidome Toshifumi , Kawazumi Hirofumi 
Published: July 2006

Abstract
The elecron energy-loss spectrum of dimethyl ether was measured at electron energies of 50, 20 and +2(residual energy) eV and at scattering angles of 0–90°. Six new bands were observed at about 6.4, 7.0, 7.5, 7.8, 8.2, 8.9 eV and assigned as the singlet-triplet and/or symmetry-forbidden transition.
Some Multinuclear NMR Solution and Solid State Studies on 1,8-Bis(dimethylamino)naphthalene and Its Complex with Tetrazole
Authors: Grech E , Stefaniak L , Ando Isao , Yoshimizu Hiroaki , Webb Graham A , Sobczyk L 
Published: July 2006

Abstract
13C and 15N NMR spectra are measured for 1,8-bis(dimethylamino)naphthalene and its complex with tetrazole in both solution and the solid state. On the basis of the solution and solid state 15N results, an equilibrium involving the half protonated form of the base in the solution of the complex salt was identified. On the other hand, it is found that the 13C results for the solutions are closely similar to those found for the solid state, and are rather insensitive to salt formation.
Aluminium-Bearing Ferrite Formation from γ-FeOOH in an Aqueous Suspension
Authors: Ito Kazuo , Tamaura Yutaka , Katsura Takashi 
Published: July 2006

Abstract
Stoichiometric Al-bearing ferrites[AlxFe3-xO4 (x=0.05–0.46)] are formed by a transformation reaction from γ-FeOOH in an aqueous suspension. The transformation reaction proceeds in a suspension containing γ-FeOOH, Fe(II) and Al ions without oxidation at 25°C and a pH of 9.5–11.0.
Preparation of Optically Active (S)-2-Aminoalkylphosphonic Acids from (S)-Amino Acids without Racemization
Authors: Oshikawa Tatsuo , Yamashita Mitsuji 
Published: July 2006

Abstract
Optically active (S)-2-aminopropylphosphonic and (S)-2-amino-4-methylpentylphosphonic acids were synthesized from commercially available chiral α-amino acids [(S)-(+)-alanine and (S)-(+)-leucine] without racemization.
Photolysis of Tetraarylmethanes and 3-(Triarylmethyl)pyridines
Authors: Shi Min , Okamoto Yoshiki , Takamuku Setsuo 
Published: July 2006

Abstract
Upon UV irradiation in benzene–methanol (1:2) tetraarylmethanes or 3-(triarylmethyl)pyridines underwent an α,α-elimination of two aryl groups to give biaryls or 3-arylpyridine, and two corresponding carbene intermediates. The latters afforded methyl ethers by the O–H insertion to methanol.