bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electronic Absorption Spectra and Geometry of Radical Ions of Tetraphenylethylene
Authors: Suzuki Hiroshi , Koyano Kinko , Shida Tadamasa , Kira Akira 
Published: July 2006

Abstract
The geometry of the radical ions of tetraphenylethylene was studied by means of electronic absorption spectroscopy. The spectrum of the anion radical produced by γ-ray irradiation in frozen 2-methyltetrahydrofuran changes markedly on controlled warming. The resultant spectrum resembles the spectra of the anion radical in fluid solutions produced by potassium reduction and by pulse radiolysis. These spectra are distinctly different from the spectra of diphenylmethanide ion and of diphenylmethyl radical. From these facts it is inferred that the relaxed anion radical has a geometry in which the central ethylenic bond is twisted by an angle considerably smaller than 90°, in contrast with the near 90° twist in the dianion, and in which each bond connecting a phenyl group with an ethylenic carbon atom is twisted by a smaller angle than in the molecule. The spectrum of the cation radical produced by γ-ray irradiation in frozen matrices is similar to that of the cation radical produced by pulse radiolysis in fluid solutions and changes only slightly on controlled warming. The geometry of the relaxed cation radical is suggested to be similar to that of the molecule, in contrast with that of the anion radical.
The Mass-transfer Rate through the Liquid–Liquid Interface. VII. Diffusion through a Spherical Interface Involving the Adsorption-Desorption Process
Authors: Shimbashi Teruya 
Published: July 2006

Abstract
A theoretical formula for the transfer rate of a solute through a spherical interface has been proposed, considering the adsorption-desorption process and the variation in the amount of adsorption. Computational results indicate that, in the usual particle-diameter (radius&lt;1 mm), the diffusion coefficient has practically no relation to the transfer rate in the case of a significant interfacial resistance, such as is observed in the transfer of fatty acids. The concentrations of butylamine in the aqueous, continuous phase in a stirred extraction vessel have been predicted.
Direct Measurement of Interaction Energy between Solids and Gases. IV. Acidic and Catalytic Properties of Amorphous and Crystalline Alumino-silicates
Authors: Masuda Tatsuo , Taniguchi Hitofumi , Tsutsumi Kazuo , Takahashi Hiroshi 
Published: July 2006

Abstract
Surface acidities and acid strength distributions of amorphous silica–alumina, Y-type faujasite and mordenite have been examined by measuring the differential heats of adsorption of ammonia. The number of acid sites with adsorption heats higher than 70 kJ/mol increased in the order: NH4Y&gt;NH4M&gt;RENH4Y&gt;silica–alumina. On the other hand, the order of the acid strength was: NH4M&gt;RENH4Y&gt;silica–alumina&gt;NH4Y. The high catalytic activities of zeolites for cumene cracking and toluene disproportionation were correlated with acid strength, Bronsted acidity, and electrostatic effect.
Decay of Naphthalene Phosphorescence in the Presence of Some Chlorinated Compounds. An External Heavy Atom Effect
Authors: Ebara Nozomu , Yajima Yusuke , Watanabe Hiroshi 
Published: July 2006

Abstract
The decay of the phosphorescence of naphthalene in the mixed solutions of methylcyclohexane and several chlorinated compounds has been analyzed. In many cases the decay was almost exponential and the decay constant was a function of the concentration of chlorinated compounds. In the case of carbon tetrachloride, the decay was distinctly non-exponential. The decay was analyzed by a Laplace transformation method. In this case a complex was formed, in equilibrium with the free naphthalene molecule, and the decay constant of the former increased when the concentration of CCl4 increased. The external heavy atom effect takes place in two ways: one by complex formation with the molecule containing heavy atoms and another by a long range interaction through a statistical distribution of the latter molecules around the phosphorescing molecule.
A Molecular Orbital Approach to the Electrophilicity of H and OH Radicals
Authors: Imamura Akira , Hirao Kimihiko 
Published: July 2006

Abstract
We tried to explain the electrophilicity of radical reagents such as H and OH radicals in the aromatic substitution reaction by using the molecular orbital theory. The delocalization energy of π electrons was decomposed into two parts: one is the energy due to the delocalization from a substrate to a reagent and another is that from a reagent to a substrate. The former was considered to be a measure of the electrophilicity and the latter of the nucleophilicity. The decomposition of the delocalization energy into two parts was carried out by modifying the relevant core resonance integrals as appropriate. The result indicated that the delocalization energy for the electrophilicity was much larger than that for the nucleophilicity for both radicals. Thus, H and OH radicals should be electrophilic in nature, in good agreement with the experimental facts. Finally, the origin of the electrophilicity was discussed in connection with the height of the relevant energy levels by following a perturbational approach.
Raman Spectra of a Compound under Inversion Motions: N,N′-Dimethylpiperazine
Authors: Fukushima Kunio 
Published: July 2006

Abstract
Raman spectra of methanol and aqueous solutions of N,N′-dimethylpiperazine were measured. Forms of stable conformers in various states were studied by comparison of the spectra obtained under various conditions. It was found that hydrogen bonding to nitrogen atoms of N,N′-dimethylpiperazine causes a conformational change.
An Application of Neutron Activation Analysis to Biological Materials. III. Natural Abundance of Small and Micro Amounts of Elements and Their Interactions in Human Tissues
Authors: Terai Minoru , Akabane Akiko , Matsumoto Michio , Hashimoto Keisuke 
Published: July 2006

Abstract
The natural abundance of the principal inorganic elements in five human tissues (brain, kidney, lung, liver, and heart) have been determined by neutron activation analysis. Cl, K, and Mn are equally distributed in all tissues. The highest concentration of Sc(0.22±0.044 ppm) is found in the liver. V(0.64±0.51 ppm) and Cr(0.19±0.11 ppm) concentrations in the lung are significantly higher than in other tissues at a 95% confidence level. The lowest concentration of Br(2.7±1.8 ppm) is found in the brain. The highest concentration of Cd(74±11 ppm) appears in the kidney and differs significantly from that in other tissues. Significant correlations appear to exist between many pairs of elements in the kidney and the lung, whereas there are relatively few in the liver. The normal significant correlations between Na, Cl, K, Sc, Zn, Se, Cd, and other elements are given.
Liquid Structure of Carbon Tetrachloride and Long-range Correlation
Authors: Nishikawa Keiko , Murata Yoshitada 
Published: July 2006

Abstract
The diffraction of liquid CCl4 was measured by using the energy-dispersive X-ray diffractometer. The fine structure was observed for the first time in the present study. The existence of the fine structure in the diffraction pattern shows the long-range correlation “directly.” The bcc cluster model for liquid CCl4 is presented on the basis of the long-range correlation. The calculated intensity of the model is in good agreement with the observed one.
Studies on Biologically Active Pteridines. II. Synthesis of Some 2-Pyrimidinyl- and 2-Pteridinyl-amino Acids
Authors: Sugimoto Takashi , Shibata Keiko , Matsuura Sadao , Nagatsu Toshiharu 
Published: July 2006

Abstract
Synthesis of some pyrimidines and pteridines with an amino acid residue at the 2-position was investigated. 4-Ammo-6-hydroxy-2-methylthio-5-nitrosopyrimidine, on heating with amino acids in water, underwent aminolysis at the 2-position to give the corresponding N-(4-amino-6-hydroxy-5-nitroso-2-pyrimidinyl) amino acids. These (5-nitroso-2-pyrimidinyl)amino acids, after reduction of the nitroso group to an amino group, condensed with biacetyl or a pentose phenylhydrazone to give N-(4-hydroxy-6,7-dimethyl-2-pteridinyl) amino acids and N-(4-hydroxy-6-polyhydroxypropyl-2-pteridinyl) amino acids, respectively.
An Examination of the Displacement Reactions in Alkyldicyclohexylborane and Alkyldi-exo-norbornylborane
Authors: Taniguchi Hiroaki 
Published: July 2006

Abstract
Displacements involving the reaction of olefins with alkyldicyclohexylborane and alkyldi-exo-norbornylborane were studied. In the case of alkyldicyclohexylborane, the 1-ethylbutyl group could be displaced selectively by 1-decene to produce hexenes. However, the hexyl group could not be displaced selectively, the reaction proceeding to produce both 1-hexene and cyclohexene. In contrast, in the case of alkyldi-exo-norbornylborane, the norbornyl group bonded so tightly to the boron atom that it was possible to displace both the 1-ethylbutyl and the hexyl groups selectively and completely by 1-decene with no loss of 2-norbornyl-boron bonds. The results suggest the possibility of contrathermodynamic isomerization of olefins by the combination of “isomerization-displacement” with di-exo-norbornylborane.
New Applications of Crown Ethers. I. Primary Alkylamine–Water–Crown Ether System as a Hydroxide Ion Source in the Reduction with Carbonylhydridoferrate Anion
Authors: Wada Fumio , Ishihara Ryoji , Kamohara Yasufumi , Matsuda Tsutomu 
Published: July 2006

Abstract
Utility of the primary alkylamine–water–crown ether system as an effective source of hydroxide ion was studied by the reduction of benzylideneacetone with carbonylhydridoferrate anion. Excellent conversion and selectivity for the reduction were attained in a two-phase system (benzene–water) in the presence of dicyclohexano-18-crown-6, comparable to those obtained with use of potassium hydroxide in place of the amine. Effects of several alkylamines and crown ethers were presented. IR examination of pentacarbonyliron–butylamine-water in benzene with or without the crown ether showed that the presence of the crown ether markedly alters the route of formation of the reducing agent (s).
Acyl Cyanide. V. The Synthesis of 1-Cyano-1-alkenyl Esters by the Reaction of Acyl Cyanides with Acid Anhydrides and Isocyanates
Authors: Oku Akira , Nakaoji Shigeru , Kadono Toshio , Imai Hideki 
Published: July 2006

Abstract
The reactions of enolizable acyl cyanides (acetyl, propionyl, and isobutyryl cyanide) with acid anhydrides (acetic, propionic, butyric, isobutyric, and benzoic anhydride) in the presence of a catalytic amount of tertiary amines (pyridine, lutidines, 4-(dimethylamino)pyridine) produced the corresponding 1-cyano-1-alkenyl carboxylates. In the reactions of propionyl cyanide, (Z)-1-cyano-1-propenyl carboxylates were formed predominantly over the (E)-isomers (isomer ratios Z⁄E were ca. 80/20). The reactions of the cyanides with isocyanates also gave the corresponding 1-cyano-1-alkenyl carbamates in moderate yields, and the acid-treatments of 1-cyano-2-methyl-1-propenyl phenylcarbamate induced its annelation into 3-phenyl-1,3-oxazolidine-2,4-dione derivatives.
Electronic State of Ethoxycarbonylnitrene Generated by α-Elimination under Two-phase Conditions
Authors: Sen\={o} Manabu , Namba Tomiyuki , Kise Hideo 
Published: July 2006

Abstract
The base decomposition of ethyl p-nitrophenylsulfonyloxycarbamate in organic-aqueous two-phase systems in the presence of cis- or trans-4-methyl-2-pentene and quaternary ammonium or phosphonium halides afforded both stereospecific and nonstereospecific addition products of ethoxycarbonylnitrene. The electronic state of the nitrene was analyzed on the basis of Skell’s hypothesis.
The γ-Ray Induced Oxidation of Cyclohexene in the Liquid Dinitrogen Oxide at −18 °C
Authors: Hirokami Shun-ichi , Wojnarovits Laszlo , Sato Shin 
Published: July 2006

Abstract
The γ-radiolysis of a cyclohexene–dinitrogen oxide mixture in the liquid phase at −18 °C has been studied and the results compared with that of the radiolysis of a cyclohexene–carbon dioxide mixture in the liquid phase.5) The oxidation reaction initiated by oxygen atoms produced in the direct radiolysis of dinitrogen oxide or carbon dioxide is common for both solutions, the products being cyclohexene oxide, cylohexanone, and cyclopentanecarbaldehyde. In the dinitrogen oxide solution, however, two other oxidation processes have to be considered in order to interpret the material balance of products and the formation of other oxygenated compounds: cyclohexanol, 2-cyclohexenol, and 2-cyclohexenone. A possible reaction mechanism is discussed.
The Substituent Effect. 14. The Solvolysis of 6- and 7-Substituted 1-(2-NaphthyI)ethyl Chlorides
Authors: Tsuno Yuho , Sawada Masami , Fujii Takahiro , Yukawa Yasuhide 
Published: July 2006

Abstract
Nine of the title compounds were synthesized, and their solvolysis rates were determined in 80%(v/v) aq acetone at 45 °C. The effects of the pi-donor substituents for each substituent position are shown to be excellently described in terms of inductive(I) and pi-electronic(Pi) effects by means of the LSFE equation (logk⁄k0=ρiσi+ρπ+σπ+), Just as with those in the 1-naphthyl systems. When those data are joined with all our substituent effects data for the phenyl, 4-biphenylyl, 2-fluorenyl, and 1-naphthyl systems under identical conditions, it is clear that the overall correspondence between the ρi values and Dewar’s simple-field-effect function (1⁄r) is satisfactory. On the other hand, the ρπ+ values appear to give slightly different responses (separate correlations for the 1- and 2-naphthyl systems) to the SCF-π charge difference values; this may be ascribed to the steric effects on the Pi effect in only the 1-naphthyl-solvolysis sets. Furthermore, the position constancy of the I effect (ρi,6−X−2⁄ρi,7−X−2=0.85) has been observed in the present solvolysis and the available data for dissociation of 2-naphthalenecarboxylic acids involving relatively weak Pi effects; the figure is in good agreement with the ratio of ρi,para⁄ρi,meta=0.85. Analogous results were also achieved by the same treatment to 2-benzo[b]thienyl reactivities. All the results are discussed with respect to the validity of the LSFE equation.
Conductometric Study of Ion-Ion and Ion-Solvent Interactions. I. Conductances of Silver Acetate in 0–50% (w/w) Methanol–Water Mixtures at 35 °C
Authors: Ananthaswamy J , Sethuram B , Navaneeth Rao T 
Published: July 2006

Abstract
Conductances of the solutions of silver acetate in 0 to 50% (w/w) methanol–water mixtures were measured at 35 °C. The association constants and molar conductances at infinite dilution were calculated using the Shedlovsky extrapolation technique and the Fuoss-Hsia equation with Fernandez-Prini coefficients. The logKA vs. 1⁄D plot passes through the origin in accordance with the Denison-Ramsey theory of ion-pair formation. The results were interpreted in terms of the equilibrium between the solvent separated ion-pairs (SSIP) and contact ion-pairs (CIP).
Preparation and Characterization of Complexes of Dichlorobis(cyclopentadienyl)zirconium(IV) with Bidentate, Terdentate, and Quadridentate Schiff Bases
Authors: Gupta Gopal , Sharan Ram , Kapoor Ramesh N 
Published: July 2006

Abstract
Bis(cyclopentadienyl)zirconium(IV) Schiff base derivatives have been synthesized by treating dichlorobis(cyclopentadienyl)zirconium(IV) (Cp2ZrCl2) with bidentate Schiff bases (SBH) viz., N-salicylidenaniline, N-salicylidene-o-toluidine, N-salicylidene-m-toluidine, N-salicylidene-p-toluidine, and N-(2-hydroxyl-1-naphthyliden)aniline, terdentate Schiff bases (SB′H2) viz., N-(3-oxo-1-methylbutyliden)-o-aminophenol and N-(3-oxo-1-phenylbutyliden)-o-aminophenol; quadridentate Schiff base (SB″H2) N,N′-disalicylidene-o-phenylenediamine, in THF, in the presence of triethylamine at room temperature. The resulting derivatives of the type Cp2Zr(SB)Cl, Cp2Zr(SB)2, Cp2Zr(SB′), Cp2Zr(SB″), and (Cp2ZrCl)SB″ [where [SB]−, [SB′]2−, and [SB″]2−-represent the anion of corresponding Schiff bases SBH, SB′H2, and SB″H2] have been characterised by their elemental analysis and by IR, electronic spectra, electrical conductance and molecular weight determinations.
Synthesis and Absorption Spectra of Some 6-Hydroxythiazolo[3,2-a]-benzimidazoles and Their Quaternary Derivatives
Authors: Soni R P , Saxena J P 
Published: July 2006

Abstract
A series of substituted 6-Hydroxythiazolo[3,2-a]benzimidazoles has been synthesized. Their quaternary derivatives showed characteristic absorption maxima at longer wavelengths in visible region. The spectral study of parent compounds in the visible region shows a red shift at higher pH which is attributed to the dipolar nature of these compounds.
Magnetic Studies on Basic Salts of Copper, Dicopper Arsenate Hydroxide, Dicopper Hydroxide Phosphate, and Dicopper Oxide Sulfate
Authors: Asai Takeshi , Saheki Hiroshi , Kiriyama Ryôiti 
Published: July 2006

Abstract
Magnetic susceptibilities, χ, of Cu2AsO4(OH), Cu2(OH)PO4, and Cu2OSO4 have been measured from 4.2 to 360 K to establish the role of the OH− and O2− ions in the magnetic superexchange interaction. The former two compounds showed a broad maximum for χ at 118 and 110 K, respectively. Although the crystal structure is three-dimensional, only a tetramer model with two parameters can explain the temperature dependence of χ, since the hydroxide anion causes a strong magnetic interaction which is limited to four copper atoms between which the anion is intermediary. The magnetic susceptibility of Cu2OSO4 obeyed the Curie-Weiss law above 140 K with a Weiss constant of −56 K. At 16 K the compound transformed into a ferrimagnetic phase, the effective megneton number of which is 0.11 at 4.2 K. A canted ferrimagnetic structure has been proposed and the canting angle estimated. In the superexchange interaction, only hydroxide and oxide anions are significant and both anions behave similarly.
The Polarographic Reduction and UV Spectral Properties of Pentaamminecarboxylatoruthenium(III) Complexes
Authors: Ohyoshi Akira , Yoshikuni Kenichiro 
Published: July 2006

Abstract
Pentaamminecarboxylatoruthenium(III) complexes are reversibly reduced to the corresponding Ru(II) complexes by means of a one-electron transfer at the dropping mercury electrode in aqueous solutions. The absorption maxima, which ranged from 34.6×103 cm−1 (trichloroacetato complex) to 33.6×103 cm−1 (glycinato complex) were assigned to the charge-transfer from ligand to metal; they were linearly related to the reversible half-wave potential.
Metal-substitution of 12-Heteropolymolybdate with Iron Atoms
Authors: Nomiya Kenji , Sugaya Motoki , Miwa Makoto 
Published: July 2006

Abstract
Triheteropolymolybdates of [XFeMo11O40H2]-and [XFeMo11O40H3]-type have been synthesised by the metalsubstitution reaction of 12-heteropolymolybdate of [XMo12O40]-type (X is Si or P) and their properties have been investigated.
Studies of Tritylated Pentoses and 6-Deoxyhexoses. II. Trityl Ethers of Methyl a- and β-l-Rhamnopyranoside and Their Derivatives
Authors: Otake Toshiki , Sonobe Toru , Suami Tetsuo 
Published: July 2006

Abstract
Mono-O-trityl derivatives of methyl α- and β-l-rhamnopyranoside have been prepared and the structures established by PMR analysis.
New Synthesis of Alkyl Polysulfides by Treatment of Thiols, Disulfides and Thionitrites with Anhydrous Copper(II) Chloride
Authors: Kim Yong Hae , Shinhama K\={o}ichi , Oae Shigeru 
Published: July 2006

Abstract
Reaction of several divalent organic sulfur compounds with copper(II) chloride in acetonitrile gave the corresponding disulfides or other polysulfides in good yields under mild conditions.
Reactive Troponoids and o-Aminophenol. IV. The Synthesis of 8-Arylazocyclohepta[b][1,4]benzoxazine by the Reaction of Arylazotropolone with o-Aminophenol
Authors: Someya Taichi 
Published: July 2006

Abstract
8-Phenylazocyclohepta[b][1,4]benzoxazine was obtained by the dehydration of 5a-hydroxy-8-phenylhydrazonocyclohepta[b][1,4]benzoxazine, which had itself been obtained by the reaction of 5-phenylazotropolone with o-aminophenol.
Selective Spectrophotometric Determination of Zinc with Di-2-pyridylmethanone 2-Pyrimidylhydrazone
Authors: Singh R B , Kulshreshtha H , Garg B S , Singh R P 
Published: July 2006

Abstract
Synthesis of a new 2-pyrimidylhydrazone i.e. di-2-pyridylmethanone 2-pyrimidylhydrazone (DPMPH) and its application in the selective determination of microamounts of zinc is presented. DPMPH reacts with zinc to form a yellow complex in the pH range 7.9–11.1 with molar absorptivity 5.2×104 l mol−1 cm−1 at 430 nm. Beer’s law is obeyed up to 1.56 ppm of zinc. Zinc has also been determined in several alloys.
On Thallium(I) Chelates of 1,2-Cyclohexanediamine-N,N,N′,N′-tetraacetic Acid and Diethylenetriaminepentaacetic Acid
Authors: Anderegg Giorgio , Bottari Emilio 
Published: July 2006

Abstract
The stability constants of the complexes mentioned in the title obtained by us by potentiometric pH measurements are compared with those of Kodama et al. Because sodium ion forms quite a stable 1,2-cyclohexanediamine-N,N,N′,N′-tetraacetate (CyDTA) complex, the discrepancy of the values can be explained. Further new calculations confirm the formation of protonated chelate with CyDTA but in a very limited pH range.
The Crystal Structures of Methylammonium Hexachlorostannate(IV) in the High- and Low-temperature Phases Studied by X-Rays
Authors: Kitahama Katsuki , Kiriyama Hideko , Baba Yoshihisa 
Published: July 2006

Abstract
The title compound crystallizes in the trigonal space group R\bar3m with a=7.171, c=21.952 Å, and Z=3 at 298 K. The crystal structures at 298 and 120 K, as well as the lattice parameters in the temperature range 113–298 K, have been determined by X-rays, in order to elucidate the mechanism of the phase transition occurring at Tt=156 K. The structure of the high-temperature phase is essentially the same as that determined by Wyckoff, except for the discrimination between C and N atoms. No change in the space group nor in the basic structure was detected over the temperature range studied, in spite of a strong suggestion from previous 35Cl-NQR measurements. A small but significant anomaly associated with the transition is recognized in the c axis, which retains almost the same length near and below Tt. As a result, the lattice shrinkage below Tt becomes increasingly anisotropic as the temperature is lowered, whereas the thermal expansion above it is relatively isotropic.
Temperature Dependence of Reorientational and Vibrational Relaxation Times of Benzene and Benzene-d6 in Solid and Liquid Phases
Authors: Nomura Hiroyasu , Koda Shinobu , Miyahara Yutaka 
Published: July 2006

Abstract
The temperature dependences of reorientational and vibrational relaxation times of benzene and benzene-d6 in the solid and liquid phases were measured by means of Raman line shape analysis. The temperature dependence of the reorientational relaxation times was in very good agreement with that published previously. The vibrational relaxation times of benzene changed drastically at the solid to liquid phase transition point both in C6H6 and C6D6. We consider that this effect is due to the non-radiative energy transfer and the pure dephasing process by molecular collisions in the liquid state.
A Kinetic Study of the Reaction of Arylthiotrimethylsilane with Carboxylic Acid Giving Acyloxytrimethylsilane and Arenethiol
Authors: Kozuka Seizi , Kitamura Takuro 
Published: July 2006

Abstract
The mechanism of the reactions of arylthiotrimethylsilanes with carboxylic acids has been studied kinetically. The reaction was found to obey a second-order kinetic equation. The substituent effects of the aryl moiety (ρ=−2.4) and of the silicon atom, the hydrogen-deuterium kinetic isotope effect of the acid (kH/kD=3) were observed. A mechanism involving the 5-coordination of the silicon atom prior to the rate-determining protona-tion of the sulfur atom has been suggested for the reaction. A remarkable base catalysis was observed. The formation of the coordinated intermediate has been suggested to be the slow step in the presence of a bese.