bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mixed-ligand Complexes of Copper(II). I. An ESR Study of Coordination Bonding
Authors: Yokoi Hiroshi , Otagiri Masaki , Isobe Taro 
Published: July 2006

Abstract
The sample solutions were prepared by mixing equal volumes of any two of the 1.00×10−2 mol/l solutions of the 1:2 complexes of copper(II) with ethylenediamine, N,N-dimethylethylenediamine, N,N-diethylethylenediamine, 1,3-diaminopropane, l-alanine, l-serine, N,N-diethylglycine, and β-alanine, where an equivolume mixture of water and methanol was used as the solvent. The X-band ESR measurements for these sample solutions were carried out at the temperature of liquid nitrogen. The observed ESR line shapes showed that only the mixed-ligand complexes are formed almost quantitatively in all the solutions except two: equivolume mixtures of the two complex solutions of ethylenediamine and β-alanine and those of ethylenediamine and N,N-dimethylglycine, in which the coexistence of two or more complex species was clearly demonstrated. The ESR line shapes and, furthermore, the intensities of the visible absorption indicated that the symmetry of the ligand field of the mixed-ligand complexes is as axial as that of the parent complexes. The ESR experimental results showed that the g⁄⁄ value of a mixed-ligand complex almost equals the mean of the g⁄⁄ values of its two parent complexes, but that there is not such a clear correlation between their A⁄⁄ values. It was interestingly concluded from the determined g values that the covalency of the metal-ligand bonds of a mixed-ligand complex are intermediate in degree between those of its two parent complexes.
Mixed-ligand Complexes of Copper(II). II. A Study of Dismutation Constants
Authors: Yokoi Hiroshi , Otagiri Masaki , Isobe Taro 
Published: July 2006

Abstract
The dismutation constants for mixed-ligand complexes of copper(II) involving, as bidentate ligands, ethylenediamine, l-alanine, β-alanine, and N,N-dimethylglycine were determined at two or three temperatures by both the spectrophotometric and ESR methods, and the thermodynamic constants were then derived from those data. It was found for these systems that the entropy change plays a main role in governing the equilibrium between a mixed-ligand complex and its parent complexes, and that the differences in the dismutation constants among the mixed-ligand complexes are due to the small but different values of the enthalpy term.
Stability Constants of Alkaline Earth Metals with o-Arsono-o′-hydroxy Azo Compounds
Authors: Kina Kenyu , Tôei Kyoji 
Published: July 2006

Abstract
The acid dissociation constants of the o-arsono-o′-hydroxy azo compounds, and their chelate stability constants with alkaline earth metals, have been measured by the pH titration method at an ionic strength of 0.10 and at 25.0±0.1°C. These azo compounds were synthesized by the coupling reaction of diazotized o-aminophenylarsonic acid with naphthol sulfonates. As the coupling components, 1,8-dihydroxynaphthalene-3,6-disulfonic acid (chromotropic acid), 2-hydroxynaphthalene-3,6-disulfonic acid (R acid), and 1-hydroxynaphthalene-3,6-disulfonic acid were used. o-Arsonophenylazochromotropic acid (Neo-Thorin) formed the most stable chelates. It was concluded that the stabilization of the metal chelate ring of the Neo-Thorin was due to a quasi-aromaticity of the six-membered ring which was produced by the hydrogen bond between two naphtholic hydroxyl groups of chromotropic acid. The metal chelate stability order, Mg&gt;Ca&gt;Sr&gt;Ba, is parallel to the reciprocal of the ionic radii of the metal ions.
Analytical Study of the Lead Ion-selective Ceramic Membrane Electrode
Authors: Hirata Hiroshi , Higashiyama Kenji 
Published: July 2006

Abstract
The lead(II) ion-selective ceramic membrane electrode developed by sintering a mixture of lead, silver, and cuprous sulfides showed sensitivity, selectivity, and other response characteristics well suited to analytical utilization. The Nernstian slope was obtained over a concentration range from 10−1 to 10−6m Pb2+ in activity, and the analytical range had a concentration of 10−1–10−7m when the membrane contained less than 30 wt% of cuprous sulfide and more than 1 wt% of lead sulfide. Among the common ions, silver, cupric, mercury(II), ferric, sulfide and iodide ions interfered seriously. About 10 times as many cadmium and bromide ions and more than 1000 times as many alkali metal, alkaline earth metal, zinc, aluminum, nickel, manganese(II), cobalt, and nitrate ions did not interfere with the lead ion, however. The electrode potentials did not change over a pH range from 2 to the pH at which the precipitation of lead hydroxide occurred. The electrode was safely used at temperatures from 0 to 95°C, and the potentials of the membrane satisfied the Nernstian equation within the limits of experimental error. The membrane electrode responded to activity changes very quickly: the rate of those changes was twice that in a lead sulfide-silver sulfide two-component ceramic electrode. A continuous potential measurement for 5 months promised long-term stability and accuracy. The rapid response rate and the long lifetime suggest that the continuous monitoring of some changing systems is feasible.
Functional Group Analysis by Gas Chromatography. IV. Pyrolytic Reaction of Carboxylic Acids in Sulfur Vapor
Authors: Hara Tadashi , Ito Susumu 
Published: July 2006

Abstract
This paper deals with a quantitative gas chromatographic analysis of the product evolved by the pyrolytic reaction between carboxylic acid and sulfur vapor. About 10 mg of carboxylic acid was mixed with 2–3 g sulfur and made to react at 1000–1100°C for 10min. The gaseous product was taken in a gas sampler and subjected to gas chromatography. Carbon dioxide was produced from the carboxyl group, carbon disulfide from carbon, hydrogen sulfide from hydrogen and nitrogen molecule from nitrogen. The peak area ratios of carbon disulfide and hydrogen sulfide to carbon dioxide were found in the gas chromatogram with glycine as a standard substance, and the other carboxylic acids were analyzed on the basis of the relation between the peak area ratio and the chemical composition of glycine. Aliphatic and aromatic carboxylic acids gave satisfactory resuls by this method, but not pyridine carboxylic acid. Weighing a definite amount of sample is not needed in this method. Information concerning the chemical composition as well as the functional group of a carboxylic acid can be obtained.
Aromatic Bromination by the Use of Organic and Inorganic Thallium Salts
Authors: Uemura Sakae , Sohma Kazuhiro , Okano Masaya , Ichikawa Katsuhiko 
Published: July 2006

Abstract
Using organic and inorganic Tl salts, the following aromatic brominations were carried out in a CCl4 or HOAc solvent and were found to occur very smoothly; (A) aromatic bromination with TlBr3·4H2O, (B) aromatic bromination with Br2 in the presence of Tl(III) and Tl(I) salts, and (C) the bromination of arylthallium(III) compounds. From a study of the relative rates and selectivities of benzene and toluene, it was deduced that an arylthallium(III) compound was not involved as an intermediate in the A and B reactions, that Tl(III) salts were more effective catalysts than Tl(I) salts for the B bromination, and that the A reaction was essentially identical with the B reaction with the TlBr3·4H2O catalyst. By considering the difference in the catalytic behavior of Tl(III) and Tl(I) salts in the B reaction, probable mechanisms are suggested.
A New Rearrangement Reaction of Azoxybenzene with Arenesulfonyl Chloride
Authors: Oae Shigeru , Maeda Tetsuya , Kozuka Seizi , Nakai Mamoru 
Published: July 2006

Abstract
Azoxybenzene was found to react with arenesulfonyl chloride to afford o- or p-arenesulfonyloxyazobenzene. This new rearrangement reaction is found in various substituted azoxybenzenes and arenesulfonyl chlorides. By the use of the 18O tracer technique, the ortho rearrangement was found to proceed via an intramolecular path, while the rearrangement to the para position was intermolecular. The yields of the rearranged products were determined by the isotopic dilution technique, while the migratory aptitude was also determined by the use of azoxybenzene-1-14C. It was found that the ratio of the sulfonyloxy migration to the phenyl ring attached to the azoxy side to that of the azo side is 1 to 2 for the ortho rearrangement. On the bases of these observations, the mechanism of this new rearrangement reaction is discussed.
Studies of Azo Colors. VIII. The Azo-coupling Reactions of Active Methylene Compounds
Authors: Hashida Y\={o}ji , Kobayashi Morio , Matsui Kohji 
Published: July 2006

Abstract
The kinetics of the azo-coupling reactions of various active methylene compounds with diazobenzene-4-sulfonic acid have been studied spectrophotometrically. In the reactions of all the active methylene compounds used, it was found that the reaction rate was proportional to both the concentration of the diazonium salt and the carbanion (or enolate ion) of the azo component. In the reactions of a series of β-dicarbonyl compounds, a plot of the logarithms of the rate constants against the pKa values of active methylene compounds gave a straight line. However, the correlation between the reactivity and pKa was found unsatisfactory in the case of active methylene compounds with such electron-withdrawing substituents as NO2, CN, COR, SO2R, and Cl. These results are discussed in terms of the nucleophilicity of these carbanions.
Thermal Decomposition of Benzoyl p-Toluenesulfonyl Peroxide
Authors: Hisada Ryuki , Minato Hiroshi , Kobayashi Michio 
Published: July 2006

Abstract
Benzoyl p-toluenesulfonyl peroxide (BTP) was synthesized by addition of barium hydroxide and water to a mixture of p-toluenesulfonyl chloride and peroxybenzoic acid in dichloromethane at −15°C. Rates of decomposition of BTP in inert solvents increased rapidly as the decomposition proceeded. This autocatalysis was prevented and the reaction followed a first-order rate equation when magnesium oxide suspension was present in the medium for removal of p-toluenesulfonic acid produced by the decomposition. The products of decomposition were analyzed. When magnesium oxide suspension was present, main products were those ascribable to homolysis (biphenyl, 44mol%, in benzene; chlorobenzene, 44 mol%, hexachloroethane, 27 mol%, in carbon tetrachloride), but products ascribable to ionic reactions were also present (phenyl p-toluenesulfonyl carbonate, 22–26mol%).
Conformation of α-Aminobutyric Acid in Aqueous Solution
Authors: Akimoto Toshio , Tsuboi Masamichi , Kainosho Masatsune , Tamura Fumihide , Nakamura Asao , Muraishi Shuichi , Kajiura Teruo 
Published: July 2006

Abstract
Raman spectrum of α-aminobutyric acid has been observed in its 15% aqueous solution (neutral). By comparing it with the Raman and infrared spectra of crystal A (in which 40% of the total molecules are the T-form molecules, 36% Ga-, and 24% Gb-form molecules), crystal B (which consists only of T-form molecules), and a complex crystal of this amino acid with calcium chloride (in which 85% are the Ga-form molecules), it has been shown that the Ga-form molecules are predominant in the aqueous solution. Here, T-, Ga-, and Gb-forms have respectively the amino group, the hydrogen atom, and the carboxy group in the position trans to the methyl group in the internal rotation around the Cα-Cβ bond. Proton magnetic resonance spectrum was observed of a Cγ-deuterated product (CD3CH2CH NH3+COO−) in its aqueous solution at several temperatures in the −1.5 to 91°C range. It has been indicated that the Ca-form is more stable by about 300 cal/mole than the other two forms.
Catalytic Oxidation over Molecular Sieves Ion-exchanged with Transition Metal Ions. IV. The Oxidative Dehydrogenation of Cyclohexane
Authors: Mochida Isao , Jitsumatsu Tetsuji , Kato Akio , Seiyama Tetsuro 
Published: July 2006

Abstract
The oxidative dehydrogenation of cyclohexane over molecular sieves ion-exchanged with cupric ion (Cu(II)–Y) was investigated by means of an ordinary flow reactor with a reactant gas composed of 1.0% cyclohexane, 50% oxygen, and 49% nitrogen. The reaction was studied at temperatures between 210–350°C; here, carbon dioxide and benzene were the main products. The Cu(II)–Y was found to be a very active catalyst for the oxidation of cyclohexane as well as for that of olefins, in comparison with an ordinary cupric oxide catalyst supported on silica gel; the selectivity for benzene formation was as high as 80% below 10% conversion. Both products were found to be formed in competitive reactions. The catalytic activities were also studied on molecular sieves ion-exchanged with other transition metal ions, such as palladium (II), silver (I), and zinc (II). The relations between the catalytic activities and the heats of formation of the corresponding metal oxides per g-atom oxygen were examined; volcano-shaped correlations were observed for both benzene and carbon-dioxide formations for these catalysts. The most active catalyst was Cu(II)–Y for benzene formation, whereas it was Pd (II)–Y for the carbon dioxide formation. The meaning of the correlations was discussed according to Balandin’s explanation, based on thermochemistry, although no satisfying explanation was found. The compensation effects were observed between the activation energies and the frequency factors in these oxidations.
Oxidation of s-Butyl Alcohol by Cerium(IV)
Authors: Mathur D L , Bakore G V 
Published: July 2006

Abstract
The oxidation of s-butyl alcohol by Ce(IV) in dilute nitric acid medium has been studied. The reaction is of first order with respect to Ce(IV)but of fractional order with respect to s-butyl alcohol. A plot of inverse of alcohol concentration against inverse of observed first order rate constant gave a straight line which did not pass through the origin. This suggests an intermediate Ce(IV)-alcohol complex formation. By repeating this procedure at different temperatures the formation constants of the complex and the thermodynamic parameters for the complex formation process have been evaluated. Hydrogen, nitrate, and sulphate ions decrease the rate of oxidation. The results have been explained on the basis of equilibrium Ce4++H2O\oversetKh\ightleftarrows Ce(OH)3++H+ and assuming Ce(OH)3+ as the reactive species of Ce(IV). From the slope-intercept of straight line obtained between inverse of observed rate constant and [H+], value of Kh=6.19 at 35°C has been evaluated in dilute nitric acid at μ=2.55 m. A mechanism in which the first step is the rapid reversible formation of a complex between Ce(IV) and Substrate followed byα–C–H bond rupture in the rate determining step has been suggested.
A Theoretical Consideration of the Electron-scavenging Process in Liquid Hydrocarbons. II. Pulse Irradiation
Authors: Yamazaki Hideo , Shinsaka Kyoji 
Published: July 2006

Abstract
A mathematical treatment of the electron recombination process is presented on the basis of the extended Smoluchowski equation, which includes the effects of several positive ions as ion cores in a spur and of a scavenger. The equation is reduced to the usual Smoluchowski equation for the geminate recombination in a special case. The time dependence of the electron concentration is obtained using a successive approximation. The results of numerical calculations for various reaction parameters are presented.
Gel Filtration of Aqueous Sodium Dodecyl Sulfate
Authors: Suzuki Hitoshi , Sasaki Tsunetaka 
Published: July 2006

Abstract
Gel filtration of an aqueous solution of sodium dodecylsulfate (SDS) was carried out using Sephadex G-50 as a gel column, and the overall elution rate (Rf) of SDS was measured. The value of Rf was found to be independent of the concentration C of SDS below a certain point, above which it increased with increasing C. A sharp break point observed coincided with the critical micelle concentration (CMC) of SDS. The intermicellar concentration of SDS was estimated from the shape of the elution curve for the solutions beyond CMC, and shown independent of the total concentration C. The value of Rf for the micelle was further determined by direct measurement. The value was found to increase slightly with C above CMC, becoming practically constant above about 1.4×10−2 mol/l. It was concluded from the results that the size of the micelle also increase with the concentration above CMC. Theoretical equations were derived for the relation between Rf and C below and above CMC. Observed Rf vs. C relation fitted the equations satisfactorily, from which CMC was calculated. A rapid equilibrium between micelles and monomer ions and the independence of intermicellar concentration on C were also confirmed.
Electron Spin-Spin Interaction in the Multiplet Ground State of Non-planar Methylene Derivatives
Authors: Higuchi Jiro 
Published: July 2006

Abstract
The effect of deviation from the planar structure in electron spin-spin interaction has been semiempirically investigated for spin multiplet ground state of radicals with methylene bonds. If these bonds are not coplanar, a significant influence occasionally appears on the values of D and E, while the influence is very small if the relative orientation among the methylene bonds still does not change.
A Further Study of the Scavengeable Electron Yield in the Radiolysis of Hydrocarbon Glasses at −196°C
Authors: Kimura Toyoaki , Fueki Kenji , Kuri Zen-ichiro 
Published: July 2006

Abstract
The yield of scavengeable electrons produced by γ-irradiation in mixtures of cyclopentane and methylcyclohexane at −196°C has been determined by electron-scavenging experiments with bromobenzene. It has been found that the maximum yield of scavengeable electrons in these mixture glasses increases with an increase in the cyclopentane concentration and that it reaches the total ionization yield in a liquid hydrocarbon. The implication of these results for the yield of radiation-induced ionization in condensed systems is discussed.
The Decomposition of Energized Ethylene Formed in the Photolyses of Alkanes
Authors: Ogata Yuji , Obi Kinichi , Akimoto Hajime , Tanaka Ikuzo 
Published: July 2006

Abstract
The decomposition and the collisional deactivation of energized ethylene formed in the photolyses of ethane, propane, n-butane, and cyclobutane at 1470 Å have been studied from the change in ethylene and acetylene yields with varying pressures of alkane or nitrogen added as a deactivator. The rate constants of the collisional deactivation and decomposition of energized ethylene were determined from the experimental data. The unimolecular decomposition theory has been applied to energized ethylene, and the results compared with the experimental rate constants.
ESR Studies of Methyl Radicals Stabilized on Silica-gel Surfaces
Authors: Kubota Shozo , Iwaizumi Masamoto , Isobe Taro 
Published: July 2006

Abstract
The methyl radicals produced on silica-gel surfaces by the photolysis of methyl iodide or methane have been investigated by ESR. When the silica gel is preheated at high temperatures (above ca. 300°C), two methyl radicals which have abnormally small hfs constants are trapped on the surfaces. In the case of the photolysis of methyl iodide, these two radicals disappear by continuing uv-irradiation, and instead an ordinary type of methyl radical is produced. The former two radicals have nearly isotropic g-values, and these values are approximately equal to that of a free electron and are considered to have a non-planar structure. The adsorption sites for these radicals were estimated to be siloxane groups. On the other hand, when the silica gel is preheated at low temperatures (below ca. 300°C) the methyl radicals produced have hfs constants of the same magnitude as that of the ordinary type of methyl radical, but each proton line of the radicals is accompanied by four satellite lines. The outer satellite lines have been confirmed by measurements of the X- and K-band spectra to be a concurrent spin-flip transition of an odd electron and a nearby proton of the silica-gel surface. The models of the adsorption state of the radicals are considered.
The Separation of Aluminum from Iron by the Zone-melting of Their Complexes
Authors: Mashima Michio , Maruyama Kazuo 
Published: July 2006

Abstract
The separation of Al from Fe was attempted as a first step in the chromatographic application of the zone-melting method to metal complexes. N,N′-ethylenedianthranilic acid and benzoic acid complexes, and various organic solid solvents were prepared. The experiment was carried out with a zone speed of 6 cm/hr and a moltenzone length of 0.6–1.0 cm at 75°C. When stearic acid was used as the solvent, the recovery percentage of Al was about 75% with the benzoic acid complex and about 99% with the N′ N′-ethylenedianthranilic acid complex. Furthermore, the effective distribution coefficient and phase diagram supported due idea of the behavior of the complexes.
Studies of Aliphatic Hydroxycarboxylic Acids as Antioxidant. V. Complexes of Copper(II) with erythro- and threo-2-Methyltartaric, and meso- and threo-2,3-Dimethyltartaric Acids
Authors: Horikawa Kazuo , Masuyama Shinroku 
Published: July 2006

Abstract
The dissociation constants of erythro- and threo-2-methyltartaric and meso- and threo-2,3-dimethyltartaric acids were determined by the potentiometric titration method at the ionic strength of μ=0.1 and at 22°C. The values of the dissociation constants were pK1=3.54 and pK2=5.03 for erythro-2-methyltartaric acid, and pK1=3.28 and pK2=4.70 for the threo-form. For meso-2,3-dimethyltartaric acid, the corresponding values were 3.52 and 4.98, while the threo-form had values of 3.04 and 5.30. The complex formation of copper(II) with these acids has been investigated using Job’s method of continuous variations at the ionic strength of μ=0.2 and at 22°C. Copper-(II) and erythro-2-methyltartaric acid react in a 1 : 1 ratio at pH 2.40 and in a 3 : 2 ratio at pH 5.00. On the other hand, the threo-form does not combine with copper(II) at pH 2.40, though it does react at pH 5.00 in a 1 : 1 ratio. As for meso-2,3-dimethyltartaric acid, the complex formation in a 3 : 2 ratio was observed at pH 5.00. However, the threo-form and copper(II) react in a 1 : 2 ratio at pH 5.00. The equilibrium constants (apparent stability constants) were calculated by the method of Turner and Anderson. The values of the equilibrium constant were log K=9.71 (pH 5.00) and log K=2.02 (pH 2.40) for erythro-2-methyltartaric acid, log K=3.78 (pH 5.00) for the threo-form, log K=9.70 (pH 5.00) for meso-2,3-dimethyltartaric acid, and log K=5.19 (pH 5.00) for the threo- form. On the basis of these data, the structures of these complexes are discussed.