bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spin Trapping as Applied to Radicals Produced by the Thermal Decomposition of Di-t-butyl Diperoxyoxalate (DBPO) in Aromatic Hydrocarbons
Authors: Sueishi Yoshimi , Furui Seiji , Matsumoto Yukinobu , Yamamoto Shunzo , Nishimura Norio 
Published: July 2006

Abstract
Di-t-butyl diperoxyoxalate (DBPO) was allowed to decompose at 40 °C in benzene and xylenes, and transient radicals were trapped by some nitroso compounds. By means of an ESR simulation technique, the trapped radicals were assigned. In benzene, t-butoxyl radicals were trapped. Exceptionally, when 1,3,5-tri-t-butyl-2-nitrosobenzene(1) was used, methoxyl radicals were trapped first, but the ESR signals changed with time and methyl radicals were finally trapped. In xylenes, monomethylbenzyl radicals were exclusively trapped by 1 and 2,4,6-trimethyl-l-nitrosobenzene(2). The hyperfine coupling constant (hfcc) of β-hydrogens exhibited a negative temperature dependence for adducts formed between 1 and benzyl radicals(1-BZ), while for adducts formed between 2 and benzyl radicals(2-BZ), a positive one.
Parametrized Equations-of-Motion Method at the (1p-1h)+(2p-2h) Level. II. Simplified Treatment of σ–π Correlations
Authors: Shibuya Tai-ichi , Narita Susumu 
Published: July 2006

Abstract
The previously proposed scheme of parametrized equations of motion for the π→π* transitions of linear polyenes [Bull. Chem Soc. Jpn., 62, 701 (1989)] has been simplified in the treatment of the σ–π electron correlations. The simplified schemes seem to give results as accurate as the original one for the low-lying excited states.
A New Apparatus for Simultaneous Measurement of Acoustic Emission and Differential Thermal Analysis and Its Application to Dehydration, Phase Transition, and Decomposition Studies of Several Inorganic Salts
Authors: Shimada Shiro , Furuichit Ryusaburo 
Published: July 2006

Abstract
A new apparatus for simultaneous measurements of acoustic emission (AE) and differential thermal analysis (DTA) is described. Two fused silica cells are used as the sample and reference holders and a fused silica rod, fixed at the bottom of the sample holder, acts as the waveguide for AE signals emitted in the sample. A 140 KHz resonance frequency sensor is attached at the end of the rod to detect the AE signals which are converted by an AE tester to three parameters, the wave form, the event count rate, and the cumulative count. The technique has been successfully utilized to study the dehydration, phase transition, and decomposition of NaN3, KNO3, KClO4, CaCrO4·0.1H2O, and MgCl2· 6H2O, for which the interesting results are reported.
Syntheses and Reactions of Conjugated Dienic Thioketones
Authors: Moriyama Satoshi , Karakasa Takayuki , Motoki Shinichi 
Published: July 2006

Abstract
5,6-Dihydro-2-phenyl-3-thiobenzoyl-2H-naphtho[1,2-b]thiin (8a) and the related dienic thioketones were synthesized in 3 steps starting from 2-(phenylthio)methylenetetralin-1-thione with chalcone, 4′-chrolochalcone, 4′-methoxychalcone, 2-cinnamoylthiophen, 2-cinnamoylfuran, 1-phenyl-2-buten-1-one, and acrylophenone respetively. Similarly, 3-thiobenzoyl-2,6-diphenyl-2H-thiin (8i) was synthesized from 1-phenyl-3-phenylthio-2-propene-1-thione. All of these dienic thioketones were found to exist in stable monomeric form. The conjugated dienic thioketone (8a) reacted as α,β-unsaturated thioketone with 2-norbornene, 2,5-norbornadiene, diethyl azodicarboxylate, diphenyl fumarate, N-phenyl- and N-(p-tolyl)maleimides, 2-chloroacrylonitrile, methyl methacrylate, acrylonitrile, and styrene to give the corresponding [4+2]cycloadducts. The thioketone (8i) also reacted with 2-norbornene to give the corresponding cycloadduct. The reaction provides a useful method for the syntheses of various sulfur-containing heterocycles.
Liquid-Phase Oxidative Lactonization of Butane-1,4-diol into γ-Butyrolactone with Oxygen over Palladium Supported on K-L Zeolite
Authors: Baba Toshihide , Kameta Keiichiro , Nishiyama Satoru , Tsuruya Shigeru , Masai Mitsuo 
Published: July 2006

Abstract
Pd0 supported on K-L zeolite suspended in a liquid phase has a high catalytic activity and a high selectivity for the oxidative lactonization of butane-1,4-diol into γ-butyrolactone under oxygen at 391 K.
Alkylation of Several Nucleophiles with Alkylsulfonium Salts
Authors: Umemura Kazuyuki , Matsuyama Haruo , Kamigata Nobumasa 
Published: July 2006

Abstract
The reactions of dialkylphenylsulfonium salts (1) with several nucleophiles such as phenols, amine, enolate ion, and thiolate ions, have been investigated. The relative reactivities of the alkyl groups of sulfonium salts for the phenolate ion (hard nucleophile) were as follows; Me:Et:i-Pr =1.0:1.34:3.44. In the alkylation of the p-toluenethiolate ion (soft nucleophile) with 1, the opposite reactivity (Me:Et:i-Pr=1.0:0.22:0.03) was found. When a sulfonium salt (1e) having an optically active (S)-s-butyl group was reacted with a phenolate ion, an optically active (R)-s-butyl phenyl ether was obtained with an inversion of the configuration at the chiral carbon atom. A reaction mechanism via a sulfurane intermediate is proposed for the alkylation of the phenolate ion with alkylsulfonium salts. The relative reactivities for the alkylation of several nucleophiles with dialkylphenylselenonium salts (12) were also investigated.
Ultrasonic Study in Aqueous Solutions of Alcohols with Methoxyl and Propoxyl Groups
Authors: Nishikawa Sadakatsu , Moritsubo Yumiko , Matsuo Fumiharu , Endo Yosiaki 
Published: July 2006

Abstract
Ultrasonic absorption, velocity and density measurements were carried out in aqueous solutions of 1-methoxy-2-propanol and 3-(3-methoxypropoxy)propanol as a function of their concentrations at 25°C. A single ultrasonic relaxational phenomenon was observed in both solutions in the frequency range from 6.5 to 220 MHz. The cause was attributed to a perturbation of an equilibrium associated with the solute solvent interaction, AB(Remark: Graphics omitted.)A+B, from the concentration dependences of the relaxation frequency and the amplitude of the relaxational absorption. The rate and thermodynamic parameters were determined for the above process. It was found that the methoxyl group introduced in alcohol molecule acted as a water structure breaker while the propoxyl group promoted the water structure. Speculation of excess ultrasonic absorption in various monohydroxy alcohol aqueous solutions was carried out from the present data. In order to further confirm the participation of the solvent water molecule in the observed relaxation process, absorption measurements were carried out in methanol, dimethyl sulfoxide, and their mixed solvents with water for 3-(3-methoxypropoxy)propanol.
The Synthesis of Transition-Metal Salts of 2-Oxo-1,3-dithiole-4,5-dithiolate (dmio)
Authors: Ikegawa Shunjiro , Nogami Takashi , Shirota Yasuhiko 
Published: July 2006

Abstract
Transition-metal salts of 2-oxo-1,3-dithiole-4,5-dithiolate (dmio) were synthesized in order to develop highly conducting organic complexes. Their redox potentials were measured and compared with those of the related 1,2-dithiolate salts.
Mechanisms and Rate Constants for the Quenching of Singlet Oxygen by Nickel Complexes
Authors: Shiozaki Hisayoshi , Nakazumi Hiroyuki , Takamura Yoshikazu , Kitao Teijiro 
Published: July 2006

Abstract
An iterative numerical determination of the rate constants for both quenching of, kq, and reaction with, kr, singlet oxygen by dithiolato nickel complexes is developed. This numerical method gives accurate rate constants for a small number of kinetic runs. The substituent effects of these complexes on rate constants lead us to conclude that the complexes quench singlet oxygen by an energy-transfer mechanism. This numerical method developed for solution systems was applied to the estimation of the photofading rate of a cyanine dye on an epoxy resin plate.
Phosphorescent State of p-Fluorobenzaldehyde
Authors: Uejoh Kazuya , Shimokozono Makoto , Koyanagi Motohiko 
Published: July 2006

Abstract
Phosphorescence spectra of p-fluorobenzaldehyde have been observed in (i) the vapor phase at room temperature and in (ii) methylcyclohexane and (iii) methyl benzoate matrices at 4.2 K. From the vibrational analysis and deuteration effect it is established that the phosphorescent state is nπ* in cases i and ii while it is ππ* in case iii. A close similarity between the vapor phase emission spectra of p-fluorobenzaldehyde and benzaldehyde leads us to the conclusion that the substitution of the fluorine atom for the para hydrogen atom of benzaldehyde has little effect to the both triplet states. Several experimental data for low frequency vibrations in the excited 3nπ* state will be given by analyzing hot sequence bands of the vapor phosphorescence spectrum.
Synthesis of 2,9-Dichloro-1,10-phenanthroline from N,N′-Annelated Phenanthrolinediones
Authors: Yamada Masaki , Nakamura Yoshio , Kuroda Shigeyasu , Shimao Ichiro 
Published: July 2006

Abstract
Though the chlorination of an N,N′-annelated phenanthrolinedione, 3,6,7,9-tetrahydro-5H-[1,4]diazepino[1,2,3,4-lmn][1,10]phenanthroline-3,9-dione, gave 2,9-dichloro-1,10-phenanthroline, another dione, 3,5,6,8-tetrahydropyrazino[1,2,3,4-lmn][1,10]phenanthroline-3,8-dione, did not. It demonstrated a simultanous introduction of two chlorine substituents to non-substituted 1,10-phenanthroline via only the former intermediate.
Preparation of Tin(II) Oxide by a Homogeneous Precipitation Method
Authors: Fujita Kazumi , Nakamura Chizuko , Matsuda Keizo , Mitsuzawa Shunmei 
Published: July 2006

Abstract
The production of tin(II) oxide from tin(II) chloride and urea was found to depend on the concentration of urea. An amorphous compound was produced for a lower concentration of urea, 5SnO·2H2O was produced for a higher concentration of urea, and tin(II) oxide was produced for a middle-range concentration of urea.
Growth of CaWO4 Crystals from M2WO4(M=Li, Na, and K) Fluxes
Authors: Oishi Shuji , Hirao Minoru 
Published: July 2006

Abstract
Calcium tungstate crystals were grown from M2WO4 (M=Li, Na, and K) fluxes. Observations of the obtained CaWO4 crystals showed that a high-temperature solution of Na2WO4 was superior to both Li2WO4 and K2WO4 solutions. It was experimentally confirmed that the Na2WO4 flux chosen on the basis of the guiding principle was the most suitable.
Hydrodesulfurization of Dibenzothiophene on Iron-Exchanged Y Zeolite
Authors: Nagai Masatoshi , Matsumoto Kaoru , Uetake Kazuya , Sakikawa Noriyuki 
Published: July 2006

Abstract
An Fe(II)HY zeolite catalyst pretreated at 500 and 600 °C was highly active for the hydrodesulfurization of dibenzothiophene when the Fe(II)HY zeolite was exchanged in a solution of FeCl2 and aqueous NH3 with NaY in N2 gas, whereas the Fe(III)NaY catalyst in a solution of FeCl3 displayed a low activity.
EPR Study of the Precursors of Chelate Paramagnetic Complexes Formed in Photochemical Reactions of [Mo(cp)(CO)3]2 (cp=η5-C5H5) with o-Quinones
Authors: Hanaya Minoru , Iwaizumi Masamoto 
Published: July 2006

Abstract
Experimental evidence has been obtained by EPR spectroscopy for the paramagnetic precursors expected in the photochemical reactions of [Mo(cp)(CO)3]2 with o-quinones to produce paramagnetic chelate complexes.
Approximation Method for Solution of Rate Equations in Homogeneous Reaction Field
Authors: Fukutani Seishiro , Sakaguchi Keizo , Jinno Hiroshi 
Published: July 2006

Abstract
Analysis of a reaction mechanism by assembling the scheme with elementary reactions requires numerical solution of the reaction rate equations. The numerical procedure is time-consuming because of the stiffness of rate equations particularly when temperature varies with the reaction progress. This investigation proposed an approximation method which can save computational time for solving reaction rate equations in a homogeneous reaction field. The approximation method reduces the rate equations, which are a set of simultaneous differential equations, to independent differential equations for each species by simplifying the original equations according to the reaction characteristics; the resultant differential equations can be solved analytically within small time intervals. The validity of these differential equations was verified by comparing the obtained changes in temperature and the species concentrations in hydrogen combustion with those calculated from the original equations with the Runge–Kutta–Gill method.
Theoretical Evidence for the Presence of Linear Polyacenes in the Interstellar Medium
Authors: Aihara Jun-ichi 
Published: July 2006

Abstract
Duley and Jones recently proposed that small linear polyacenes (e.g., anthracene) were responsible for the IR emission observed in localized regions of some UV-excited nebulae. Linear polyacenes are relatively stable in the first excited state although they are not very stable in the ground state. This probably is the primary reason why this type of benzenoid hydrocarbons are observed in the interstellar medium.
Asymmetric Hydrogenation of α-Keto Acid Derivatives with Rh(I)–Chiral Diphosphinite System. Effect of Halide Counterion on the Asymmetric Induction
Authors: Yamagishi Takamichi , Ikeda Satoru , Egawa Tatsuya , Yamaguchi Motowo , Hida Mitsuhiko 
Published: July 2006

Abstract
A chiral diphosphinite ligand having dicyclohexylphosphinooxy and dimethylamino moieties (Cy-POP-AE) was effective for the asymmetric hydrogenation of N-(benzoylformyl) amino acids by a Rh(I) catalyst under mild conditions. A neutral rhodium(I) precursor enabled a double asymmetric induction in methanol, while a cationic precursor caused an asymmetric induction controlled mainly by the substrate chirality.
Novel Electron Acceptors Bearing a Heteroquinonoid System III: 2,5-Bis(dicyanomethylene)-2,5-dihydrofuran and Its Conjugated Homologues as Novel Oxygen-Containing Electron Acceptors
Authors: Ishida Hideki , Yui Koji , Aso Yoshio , Otsubo Tetsuo , Ogura Fumio 
Published: July 2006

Abstract
2,5-Bis(dicyanomethylene)-2,5-dihydrofuran with a 2,5-furanoquinonoid skeleton and its extensive conjugated homologues, 5,5′-bis(dicyanomethylene)-5,5′-dihydro-Δ2,2′-bifuran (8a), and 5,5″-bis(dicyanomethylene)-5,5″-dihydro-Δ2,2′:5′,2″-terfuran (12a), have been prepared as a new type of oxygen-containing electron acceptors. In the synthetic course of the tetrabromo derivative of 12a, 3′,4-dibromo-5-(3,5-dibromo-2-furyl)-3,5′-bis(dicyanomethylene)-3,5′-dihydro-Δ2,2′-bifuran was also obtained as an unsymmetrical isomer possessing an unusual 2,3-furanoquinonoid conjugation, whose structure was confirmed on the basis of X-ray crystallographic analysis. In addition, X-ray analysis of the TTF complex of 8a revealed that the bifuranoquinonoid conjugation has a trans form. These furanoquinonoid compounds behaved as weak electron acceptors, and accordingly failed to form conductive complexes. However, the 3,3′-dibromo derivative of 8a gave the TTT complex of a very high electrical conductivity.
Synthesis and Reactions of Phosphine–Methylsulfonyloxyborane Complexes
Authors: Oshiki Toshiyuki , Imamoto Tsuneo 
Published: July 2006

Abstract
Functionalizations of the boranato group of phosphine–boranes have been investigated. Trimethylphosphine–borane readily reacted with methanesulfonic acid in dichloromethane with evolution of hydrogen. The resulting trimethylphosphine–methylsulfonyloxyborane was subjected to nucleophilic substitution reaction on the boron atom with arenethiols or secondary phosphine–boranes in the presence of NaH. The reactivities of the substitution products obtained were also investigated. A new phosphine–borane having a P–B–P–B–P–B–P–B bond linkage was synthesized.
Highly Selective Cis-Trans Photoisomerization of 1-Pyrenylethylenes: Relations between the Modes of Isomerization and Potential Energy Surfaces
Authors: Okamoto Hiroaki , Arai Tatsuo , Sakuragi Hirochika , Tokumaru Katsumi 
Published: July 2006

Abstract
Among 1-pyrenylethylenes with an alkyl (t-butyl) or an aryl (phenyl) group on the β ethylenic carbon, 1-(3,3-dimethyl-1-butenyl)pyrene (BP) undergoes cis-to-trans one-way isomerization on benzil sensitization, whereas 1-styrylpyrene (SP) undergoes mutual isomerization between the cis and trans isomers to afford an extremely high photostationary state composition (98%) of the trans isomer. Transient spectroscopy and measurements of the isomerization quantum yields revealed that the trans triplet state is the most stable and populated conformation on the triplet energy surface for both BP and SP; however, a higher degree of stabilization of the trans conformation for BP than for SP compared to the perpendicularly twisted conformation makes BP and SP one-way and two-way isomerizing, respectively.
Normal Vibrations of 5-Chloro-, 5-Bromo-, 5-Methyl-, and 2-Methylpyrimidines
Authors: Ikari Yoshihiro , Sakamoto Hironobu , Nakama Sekiichiro , Nibu Yoshinori , Shimada Hiroko , Shimada Ryoichi 
Published: July 2006

Abstract
Assignment of the normal vibrations of 5-chloro-, 5-bromo-, 5-methyl-, and 2-methylpyrimidines was made through the vibrational analyses of the polarized Raman and infrared spectra and also through the normal coordinate calculation. The normal vibrations of 5-halo- and 5-methylpyrimidines were compared with those of 2-halo- and 2-methylpyrimidines, and a substitutional effect on the vibrational frequencies and modes of the hydrogen bending and wagging vibrations was studied.
Novel Reduction of Carbonyl Compounds with Al/NH3/Halide under Irradiation of Ultrasonic Wave
Authors: Sato Ryu , Nagaoka Takeshi , Goto Takehiko , Saito Minoru 
Published: July 2006

Abstract
Various carbonyl compounds, such as benzophenones and acetophenones, were reduced by Al/NH3/halide under ultrasonic wave irradiation to give the corresponding monohydric alcohols and/or pinacols in satisfactory yields. The addition of inorganic halides improved the selectivity in the formation of monohydric alcohols and pinacols.
The Control of the Phenylglyoxylic Acid Permeation Rate through a Liquid Membrane of a Toluene–Chloroform Mixture Containing Magnetite under a Rotating Magnetic Field and an Alternating Magnetic Field
Authors: Sakai Yasuzo , Kumakura Hiroyuki , Takahashi Fujio 
Published: July 2006

Abstract
A liquid membrane containing ferromagnetic powder (LM-FP) was proposed for controlling the molecular permeation rate through a liquid membrane in a rotating magnetic field (R-MF) in a previous paper. This paper presents details concerning the property of LM-FP under exposure to R-MF or an alternating magnetic field (A-MF). Magnetite and phenylglyoxylic acid (PGA) were used as a ferromagnetic powder and a substance for permeation, respectively. Various factors, such as the magnetite concentration in LM-FP, the intensity of the magnetic field and the number of rotations of R-MF, both of which affect the PGA permeation rate, were investigated in order to understand the behavior of magnetite powder in LM-FP. Magnetized particles of magnetite powder in LM-FP were found to rotate in R-MF, but not to move in A-MF. R-MF exerted an acceleration of the PGA permeation rate through LM-FP more than did A-MF. It is suggested that magnetized particles of magnetite powder behave as micro-magnetic stirrers in LM-FP to accelerate molecular transport. Data concerning the PGA permeation rate were simulated by assuming a concentration change of PGA in LM-FP after turning R-MF on or off. We obtained simulation curves which were in accord with the experimental results.
Correlation of Viscosity and Conductance with 23Na+ NMR T1 Measurements
Authors: Price William S , Chapman Bogdan E , Kuchel Philip W 
Published: July 2006

Abstract
The relationship between rotational correlation time and the translational diffusion coefficient (Stokes–Einstein equation) of sodium ions dissolved in a series of water–glycerol solutions was studied. NMR longitudinal relaxation measurements gave an estimate of the rotational correlation time for the hydrated sodium ion. From this, using the Debye and Stokes–Einstein equations the translational diffusion coefficient was calculated. These results were compared with estimates of the sodium ion diffusion coefficient obtained using pulsed field gradient NMR. The simple, chemical system was chosen for this study so that the nature of the sodium relaxation would be unambiguous. Also, conductivity measurements were performed on each solution since the conductivity is intimately related to the rate of ionic diffusion. The results showed that due to the spherical nature of the hydrated sodium ion the Debye and Stokes–Einstein equations are well obeyed allowing translational diffusion coefficients to be calculated from rotational correlation times in good agreement with those measured using pulsed field gradient NMR.
AMI and CNDO/S Study of 2,5-Dimercapto-1,3,4-thiadiazole, the Mesoionic 1,3,4-Thiadiazolo[2,3-b][1,3]thiazine-2-thione and Its Dimerization Derivative
Authors: Buemi Giuseppe 
Published: July 2006

Abstract
The molecular geometries of the mesoionic 1,3,4-thiadiazolo[2,3-b][1,3]-thiazine-2-thione (II) and its dimerization product, 1,10-dithia[4.4](3,5)-1,3,4-thiadiazolinophane-6,15-dithione (III) have been optimized by means of the AMI method. Their electronic spectra, as well as those of the parent 2,5-dimercapto-1,3,4-thiadiazole (I), have been calculated at CNDO/S level. The analysis of the calculated electronic transitions and of the experimental UV absorption bands confirms the mixed thiolic–thionic structure of I as the most stable one, in agreement with 4-31G* prediction. The electronic transitions of compound III are practically coincident with those found for I; on the contrary, a band in the visible and a band in the UV region are predicted for compound II, so accounting for the yellow color of II and the lack of color of III.
Micellar Effects upon Spontaneous and Alkaline Hydrolysis of t-Butyl Phenyl Carbonate
Authors: Al-Lohedan Hamad A , Al-Hassan Mohammed I 
Published: July 2006

Abstract
Cationic micelles of hexadecyltrimethylammonium ion HTAX (X=Cl− and OH−) catalyzes the reactions of t-butyl phenyl carbonate with OH− and kΨ goes through maximum with increasing [HTACl] but it continues to increase with increasing [HTAOH]. Spontaneous hydrolysis of t-butyl phenyl carbonate is inhibited by both cationic and anionic micelles. The second-order rate constant in micelles is smaller than that in water.
Transport of d-Glucosamine through a Supported Liquid Membrane System Using Lipophilic Aldehyde as a Carrier
Authors: Yoshikawa Masakazu , Mori Yoshikazu , Tanigaki Masataka , Eguchi Wataru 
Published: July 2006

Abstract
Transport of amino compound relevant to biology, d-glucosamine, was carried out with a supported liquid membrane using a lipophilic aldehyde, 4-octadecyloxybenzaldehyde, as a carrier. In the present membrane transport system, a reversible organic reaction, Schiff base formation reaction, between amino group in d-glucosamine and aldehyde group in carrier was utilized as a molecular recognition reaction.
Surface-Active Properties and Their Photochemical Behaviors of (1-Alkyl-4-pyridiniomethyl)phosphonates
Authors: Okamoto Yoshiki , Hosoda Asao , Takamuku Setsuo 
Published: July 2006

Abstract
(1-Alkyl-4-pyridiniomethyl)phosphonates bearing long alkyl-chains of even carbon numbers of 8 to 18 were prepared. They exhibited the characteristics of surface-active agents. Upon irradiation in alkaline aqueous media, the phosphonates underwent the C–P bond cleavage to give 1-alkyl-4-methylpyridinium phosphates and as a result the surface tension of the solution also changed. The two-fold increases of the quantum yields of the C–P bond cleavage were found at their critical micelle concentrations.