bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cobalt(III) Complexes with Schiff Bases Obtained from Salicylaldehyde Derivatives and Alkanol Amines
Authors: Yamada Shoichiro , Kuge Yoshio , Yamanouchi Kuniko 
Published: July 2006

Abstract
Cobalt(III) complexes with Schiff bases (X-SAL.Y-OH) obtained from salicylaldehyde derivatives and alkanol amines (H2N.Y-OH) were synthesized as crystals. Two types of diamagnetic cobalt(III) complexes were obtained, one being green (type A) and the other red (type B). In the complexes of type A with the general formula [Co(H-SAL.R)3], where R=CH2CH2CH2OH and CH2CH2CH2OCH3, the ligands are considered to function as bidentate ligands, the terminal hydroxyl or methoxy groups not being bound with the cobalt(III) ion. In the complexes of type B with the general formula Co(X-SAL.Y-OH)(X-SAL.Y-O), where X=H and 3-CH3O, and Y=CH2CH2, CH2CH(CH3) and C(CH3)2CH2, the ligands function as terdentate ligands.
The Mechanism of Photochromism, Thermochromism and Piezochromism of Dimers of Triarylimidazolyl
Authors: Maeda Koko , Hayashi Taro 
Published: July 2006

Abstract
A stable free radical, 2,4,5-triphenylimidazolyl, which was produced by oxidation of 2,4,5-triphenylimidazole, dimerizes to yield two dimers, a photochromic dimer and a piezochromic dimer. The photochromic dimer shows thermochromism and photochromism at temperatures between −196°C and about 200°C both in solution and in solid state. The piezochromic dimer shows piezochromism in solid state and thermochromism both in solution and in solid state. Spectro-scopic and kinetic studies showed that photochromism, thermochromism and piezochromism are caused by radical dissociation of the dimers of triphenylimidazolyl on irradiation, heating and grinding. Dimers of substituted triphenylimidazolyl also showed these phenomena which are due to the same mechanism as that of the dimers of triphenylimidazolyl.
Reaction of Alkylidenephosphoranes with Nitrosyl Chloride and Decomposition of α-Hydroxyiminophosphonium Chlorides Formed
Authors: Eguchi Chikahiko , Akiba Kin-ya , Inamoto Naoki 
Published: July 2006

Abstract
The reaction of stable alkylidenephosphoranes with nitrosyl chloride in THF gave α-substituted α-hydroxyiminomethyltriphenylphosphonium chloride (A) in high yields. In the case of active alkylidenephosphoranes, “transylidation” took place simultaneously and a mixture of A and α-substituted methyltriphenylphosphonium chloride was obtained along with corresponding amounts of nitrile and triphenylphosphine oxide. By thermal decomposition, all α-hydroxyiminomethyltriphenylphosphonium chlorides (A) afforded nitriles and triphenylphosphine oxide.
Study of the Sapogenins from Albizzia lebbek Benth. Seeds
Authors: Varshney I P , Badhwar Geeta 
Published: July 2006

Abstract
The seeds of Albizzia lebbek Benth. from Madhya Pradesh have been found to contain a mixture of saponins which on hydrolysis gives echinocystic acid (I), oleanolic acid (II) as major sapogenins and an unidentified sapogenin (not albigenin) in traces. The albigenic acid (III) earlier reported to be present has been shown to be an alcoholic hydrochloric acid isomerisation product of echinocystic acid.
Reactions of Thioamides with Haloacids
Authors: Shaikh Ahmedhusen , Chinone Akiko , Ohta Masaki 
Published: July 2006

Abstract
The reactions of S-carboxymethylisothioamide RC(=NR′)SCHRCOOH with acetic anhydride proceeded through various courses depending on the reaction conditions and the structure of thioamides. When S-carboxymethylisothiobenzanilide (IIa) was treated with a mixture of acetic anhydride and triethylamine in the cold, an intermediate (A), presumably 2-hydroxy-2,3-diphenylthiazolidin-4-one (V), was isolated which was readily converted to benzoylthioacetanilide (IIIa). Attempts to convert A or IIIa to a mesoionic compound failed. Under the same reaction conditions as for IIa, S-carboxymethylisothiobenz-p-chloroanilide (IIb) afforded benz-p-chloroanilide, while corresponding p-anisidide (IIc) gave only tarry product. Attempts to obtain a mesoionic product from pyrrolidine-2-thione or thiocaprolactam and bromoacetic acid were unsuccessful. However, condensation of pyrrolidine-2-thione with α-chlorophenylacetic acid followed by treatment with a mixture of acetic anhydride and triethylamine gave eight-membered rearranged product (XII).
Anionic Telomerizations of Styrene with Some Aromatic Amines
Authors: Asahara Teruzo , Sen\={o} Manabu , Tanaka Sadayoshi 
Published: July 2006

Abstract
The anionic telomerizations of styrene with some aromatic amines catalyzed by sodium metal were investigated. o-Toluidine, m-toluidine, p-toluidine, 2,4-xylidine, 2,5-xylidine and 3,4-xylidine were used as the aromatic amines. Each amine reacted with styrene to give an addition product, which was identified as N-substituted 2-phenylethylamine. Though both α-hydrogen atoms on α-carbon atoms and hydrogen atoms attached to nitrogen atoms of the aromatic amines are weakly acidic, only the latter hydrogen atoms were detached by alkali species under the present experimental conditions. The formations of the products were discussed from the standpoint of anionic telomerization.
Initial Rate and Aging Effect of Ethylene Polymerization with Ziegler-Natta Catalysts. III
Authors: Matsuda Tsuneo , Furukawa Takashi , Togo Shigeyasu , Tanaka Toyosuke 
Published: July 2006

Abstract
The initial rate and the aging effect of ethylene polymerization with TiCl4- and TiCl3-AlEt3 catalyst were investigated. The initial rate, r, was expressed by the equation; r=k1PE+k2PE2, where pE is the ethylene partial pressure and where k1 and k2 are constants. The explanation of the equation is as follows:
&(active site)+M\xrightarrowk_1(polymerization site), rate, k_1P_E
&(polymerization site)+M^*\xrightarrowk_2(propagation), rate, k_2P_E^2
M shows the ethylene monomer which is liberated by the catalyst formation or which is introduced into the system. M* is the monomer which is introduced into the system. The initial rate decreased in the TiCl4-AlEt3 system with the aging-time interval; on the other hand, in the TiCl3-AlEt3 system the rate showed its maximum at about half an hour’s aging. The optimum aging temperature was found to be 20°C. The decrease in the rates between the two systems may be ascribed to the reduction of the Ti atom in the initial valence state of the reaction to the lower valence.
Polymerization of Vinyl Chloride and Copolymerization of Vinyl Chloride with Styrene by Alkylmagnesium Chlorides
Authors: Minato Hiroshi , Oku Masayoshi , Higosaki Nobuyuki 
Published: July 2006

Abstract
t-Butylmagnesium chloride was found to initiate the polymerization of vinyl chloride efficiently at −22–30°C. The best solvent was diethyl ether, but the degree of polymerization was the highest when no solvent was used (\barPn=1940 at 20°C). The apparent activation energy for the rate of polymerization was 13.2 kcal/mol and the frequency factor was 9.06×104. The rate of polymerization, Rp, was equal to const. ×[VC]3.90×[t−BuMgCl]1.98. Isopropylmagnesium bromide initiated the polymerization with less efficiency, and phenylmagnesium bromide was completely ineffective. Vinyl chloride and styrene were copolymerized in ether by t-butylmagnesium chloride at 30°C. The mole % styrene included in the copolymer was considerably different from those obtained by benzoyl peroxide at 48°C or by di-t-butylperoxy oxalate at 30°C.
Asymmetric Reactions. IV. An Attempted Asymmetric Reduction by a Solution of [Co(CN)5]3− and Optically Active α-Amino Acid, and Its Reactive Species
Authors: Ohgo Yoshiaki , Takeuchi Seiji , Yoshimura Juji 
Published: July 2006

Abstract
Reduction of various olefines by a solution of pentacyanocobaltate and glycine or optically active α-amino acid was studied. There is no essential difference between the reactivity of [Co(CN)5H]3− to olefines and that of the solution of pentacyanocobaltate and α-amino acid. Atropic acid was reduced with the solution containing optically active α-amino acid (l-isoleucine) to give slightly optically active hydratropic acid. It was found that the main reactive species in the solution of [Co(CN)5]3− and α-amino acid was [Co(CN)5H]3− (this might be the reason for the asymmetric reduction not taking place effectively), and the reversible change between [Co(CN)5]3− and [Co-(CN)5H]3− was observed depending on the pH of the solution.
Conformations of Sequential Polypeptides Containing l-Alanyl and Glycyl Residues
Authors: Iio Takayoshi , Takahashi Sho 
Published: July 2006

Abstract
The conformations of four polypeptides containing ordered sequences of l-alanyl(A) and glycyl (G) residues, (A)n, (A3G)n, (A2G)n, and (AG2)n, are investigated in solution. The optical rotatory dispersion and infrared spectra showed that all the polymers assume both an α-helical conformation and a β-conformation in solution. The stability of the α-helix decreases in the oder: (A)n, (A2G)n, (A3G)n, and (AG2)n; this may be explained in terms of the interaction between methyl groups of l-alanyl residues regularly arranged on the surface of the α-helix.
Color Reactions of Poly vinyl Acetate and Its Derivatives with Iodine
Authors: Hayashi Sadao , Kawamura Chozo , Takayama Masanari 
Published: July 2006

Abstract
It has been found that the addition of a methanol solution containing polyvinyl acetate (PVAc) and iodine to an aqueous solution of potassium iodide results in a red-violet color without precipitating any polymer. The absorption maximum was located at 510 mμ. The absorbance of the PVAc-iodine complex decreased only slightly with an increase in the degree of the polymerization of PVAc. A linear relationship was obtained between the abosrbance and the PVAc concentration. It was found from these results that the color reaction of PVAc with iodine can be used in a colorimetric determination of PVAc, which is insoluble in water. Further, an attempt was made to investigate the complex formation of the vinyl acetate-vinyl propionate copolymer (PVAc-PVPr) and the vinyl acetate-vinyl formacetal copolymer (PVAc-PVFA) with iodine. Although the absorption maximum of the color complex of PVAc-PVPr with iodine appeared at 510 mμ, independent of the copolymer composition, the absorbance decreased with an increase in the number of vinyl propionate units in the copolymer. The absorption maximum of the complex of PVAc-PVFA with iodine was observed to lie at 620 mμ for highly-acetalyzed polyvinyl alcohol and at 520 mμ for polyvinyl alcohol of a low degree of acetalyzation, while a new absorption maximum appeared in the range from 520 to 620 mμ in the intermediate case. The absorbances at the absorption maxima of the complexes of PVAc-PVFA with iodine were approximately the same as those of PVAc. The effect of an elevated temperature on the absorbance was smaller for PVAc-PVFA than for PVAc-PVPr. From these experiments, it became clear that the glass-transition temperature and the color intensity of the polymer-iodine complex have a simple relation.
The Effect of Pressure on the Electronic Absorpion Spectra of TCNQ Ion Radical Salts
Authors: Sakai Nobuko , Shirotani Ichimin , Minomura Shigeru 
Published: July 2006

Abstract
The effect of pressure up to 7 kbar on the electronic absorption spectra of the crystalline TCNQ anion radical salts and Li(TCNQ) in PVA has been studied. For simple TCNQ salts such as Li(TCNQ), a blue shift with an increase in the pressure has been observed in the absorption band associated with the intramolecular transition. The magnitude of the blue shift is between 45 and 86 cm−1/kbar. The observed shift has been discussed in terms of the crystal-field effect of the cations. For N-MePhe(TCNQ) and M(TCNQ)2, composed of the formally-neutral TCNQ and its anion radical such as TEA(TCNQ)2, a pressure-induced absorption band has been observed at around 20 kK; it may be assigned to the charge-transfer band between the anion radicals.
A Chemical Study on Some Archaeological Samples from Iran and Afghanistan
Authors: Muroga Teruko 
Published: July 2006

Abstract
From archaeological interest, chemical analyses were performed on samples which had been collected from Iran and Afghanistan by the Kyoto University Scientific Mission to the Iranian Plateau and Hindukush. As samples were used more than one hundred pieces of glass and glazed material, and two slag-like objects. By analyzing the glass and glazes for major components, it was found that all were made of soda-lime glass except for a fragment of a glaze of tri-colored pottery collected at Kerman, Iran. It is noteworthy that this fragment of tri-colored pottery had a lead content similar to that of Chinese glazes, while Western glasses are rarely found to contain so much lead. Among the minor components detected, detailed consideration was given to the color origins. Although iron and copper were commonly found in blue-colored samples, the origin of the color of the tile from a mosque at Tabriz was confirmed to be cobalt. Investigations of slag-like objects collected from Tepe Sialk have revealed the possibility that these objects are slags from copper smelting. Studies of the silvery effect or of the weathering observed on the surface of glass and glazes of archaeological importance were carried out by semi-quantitative spectrochemical analysis.
Studies of Ion Exchange Membranes. XXXI. The Hydrogen Peroxide Treatment of the Cation Exchange Membrane of Ferric Ion Form
Authors: Mizutani Yukio 
Published: July 2006

Abstract
Neosepta CL-2.5T, the cation-exchange membrane prepared by the “Paste Method,” of the ferric-ion form was treated with hydrogen peroxide, and the changes in the membrane properties (the thickness, the water content, and the ion-exchange capacity) were measured. The porous membrane, having no ion-exchange capacity, was obtained by the treatment with hydrogen peroxide and the water permeation through the membrane was measured. Assuming the capillary model, the water-permeability data of this membrane suggested that the apparent pore radius of this membrane was 15–17 mμ and that the apparent pore distance was about 40 mμ. This suggests that Neosepta CL-2.5T contains a minute and continuous heterogeneity; i.e., there is a localized distribution of the ion-exchange resin component within the membrane.
ESR Spectra of γ-irradiated Linear Aliphatic Polyesters
Authors: Nozawa Yasuo 
Published: July 2006

Abstract
The ESR spectra of γ-irradiated linear aliphatic polyesters (2.2, 2.4, 2.6, 2.7, 2.8 and 6.8 polymer) have been measured at various temperatures ranging from 77°K to room temperature. Two types of spectra are obtained in these polyesters except for 2.2 polymer. The first, the six-line spectrum obtained at low temperatures was relatively short-lived and increased in signal intensity with increasing methylene groups of these polyesters. The well-resolved, second, five-line spectrum is stable even at room temperature in comparison with the former. The possible structures of two radicals were discussed.
The Dye-sensitized Photolysis of Hexamethyleneammonium Hexamethylenedithiocarbamate by Thiazine Dyes
Authors: Yamase Toshihiro , Kokado Hiroshi , Inoue Eiichi 
Published: July 2006

Abstract
Hexamethyleneammonium hexamethylenedithiocarbamate (HMTC) was photolyzed by UV light to yield carbon disulfide as the decomposition product. This photolysis could be sensitized by thiazine dyes, such as methylene blue and thionine. New methylene blue was the most effective among the sensitizers of this type examined. Bewteen the reciprocal concentration of HMTC and the reciprocal quantum yield, a linear relation was observed. The presence of oxygen was essential for the sensitization. Systems containing methylene blue appear to be more sensitive to oxygen than those containing thionine or new methylene blue. In the presence of an appropriate reducing agent such as allylthiourea, the quantum yield was decreased. The sensitization mechanism by thiazine dyes was probably different from that by benzophenone previously reported. It seems that the sensitization by thiazine dyes takes place by means of the interaction of the triplet state of the sensitizer with dissolved oxygen.
Biradical Spin-Labeled Micelles
Authors: Ohnishi Shun-ichi , Cyr Theodore J R , Fukushima Hiroko 
Published: July 2006

Abstract
A biradical spin-label, N,N′-di-[4-(1-oxyl-2,2,6,6-tetramethylpiperidyl)] urea, has been used for studying the dynamic structure of a micelle, sodium dodecyl sulfate (SDS). Analysis of the ESR spectra of the label has shown that the biradical was incorporated in the micelle. The tumbling motion of the label in the micelle was not strongly inhibited, suggesting a dynamic character of the micelle structure. The exchange rate of the biradical between the micelle and the water phases was slower than 107sec−1. The partition coefficient expressed as the ratio of the concentration of the biradical in the micelle to that of the biradical in the water phase was approximately 6×105 in the SDS concentration lower than 2×10−2m. The biradicals form aggregate in the micelle, when they are present in excess in the solution.
Studies of the Structure of Polyurethane Elastomers. I. The Number-average MW Determination of the Hard-segment in the Poly(Ether)Urethane Elastomer by Means of Perchloric Acid Depolymerization
Authors: Suzuki Hajime , Ono Hiroshi 
Published: July 2006

Abstract
Urea segment which is called a hard-segment in the poly(ether)urethane elastomer (PEUE) consisting of a polyether segment,urethane segment,and urea segment was isolated by means of perchloric acid depolymerization. The number-average molecular weight (MW) of the urea segment obtained by the above method was determined by elemental analysis and by volumetric analysis. By comparing the analytical results with the results calculated for a random polymerization, the number-average MW of the hard-segment was found to deviate from that expected from the equal reactivity of the two isocyanate groups in 4,4′-diphenyl methane diisocyanate (MDI). Therefore, an apparent reactivity ratio of two isocyanate groups in MDI (A) can be calculated from the number-average MW of the hard-segment isolated by means of perchloric acid depolymerization.
Studies of the Structure of Polyurethane Elastomers. II. The Determination of the Blockiness of Poly(Ether)Urethane Elastomes
Authors: Suzuki Hajime , Ono Hiroshi 
Published: July 2006

Abstract
Two types of poly(ether)urethane elastomers (PEUE), which had the same composition ratio but different degrees of blockiness, were synthesized by the reaction of 4,4′-diphenyl methane diisocyanate (MDI), polyoxytetramethylene glycol (PTG), and hydrazine (HD) or ethylenediamine (EDA) by means of the prepolymer method. The degree of blockiness of the PEUE thus synthesized by the reaction of MDI, PTG, and HD was determined by measuring the molecular weight of a hard segment (urea segment), itself obtained by perchloric acid depolymerization. The values of the blockiness of PEUE which had been synthesized by the prepolymer method without any solvent or in a solvent by means of a prepolymer reaction were about 0.4 and 0.7 respectively. The degree of the blockiness of the PEUE prepared from MDI, PTG, and HD, as measured by the above method, corresponded to the infrared absorbance ratio of the PEUE synthesized by the reaction of MDI, PTG, and EDA at 1740 cm−1 and 1720 cm1. From these results two infrared absorbances, at 1740 cm−1 and 1720 cm−1, were assigned to the urethane linkage in a soft segment and at the end of an urea segment respectively.
Diffuse Reflection Spectra of Acid Clays Colored with Benzidine and Some Other Diamines
Authors: Hakusui Akihiko , Matsunaga Yoshio , Umehara Kenji 
Published: July 2006

Abstract
In order to identify the species responsible for the coloration of acid clay upon the addition of benzidine and related aromatic diamines, the diffuse reflection spectra of colored clays in the presence of water, methanol, and benzene were examined in the range from 4 to 29 kK. The coloration appeared to be due to the oxidation of the diamines held between the silicate sheets to the mono-and di-valent cations. The former cations were found to be in various modes of intermolecular interaction, depending on the kind and amount of the liquid. The lightening of the color upon drying was attributed to the disproportionation of the monovalent cations to the divalent cation and the protonated molecule.
Calculation of the Hyperfine Coupling Constants of Some σ Electron Radicals
Authors: Yonezawa Teijiro , Kawamura Takashi , Kato Hiroshi 
Published: July 2006

Abstract
The isotropic hyperfine coupling constants of cyclopropyl, vinyl, formaldiminoxy, formyl, and hydrogen cyanide anion radicals are calculated by a method which corresponds to the extension of the McLachlan procedure. These hyperfine coupling constants are then studied, and the contributions from the spin delocalization and spin polarization mechanisms are estimated. The role of one-center exchange integrals in the estimation of these hyperfine coupling constants is also studied; it is shown to be important in the claculation of the hyperfine coupling constants of the nuclei of the radical-center atom and of the atoms bonded to it.
On the Ligand Exchange Equilibrium in the Propylene-Mercury(II) Complex
Authors: Kawai Itsuro , Nakajima Riichiro , Hara Tadashi 
Published: July 2006

Abstract
The equilibrium between the propylene-mercuric complex and either Cl−, Br−, I−, or EDTA, and their dependences on the pH were investigated manometrically. The propylene-mercuric complexes present in the above equilibrium were found to be (HO−)n-Hg2+-Propylene (n=0, 1 and 2) and (HO−)n-Hg2+(X−)-Propylene (n=0 and 1), and their equilibrium equations were:
& (HO^-)_n-Hg^2++Propylene\oversetK_p1\ightleftharpoons(HO^-)-Hg^2+-Propylene
& X^--Hg^2+-(HO^-)_n+Propylene\oversetK_p2\ightleftharpoons(HO^-)_n-Hg^2+(X^-)-Propylene.
By introducing Kp1=K′p1 and Kp2=K′p2 when n=0, the dependences on the pH were shown by:
logK_p1=logK’_p1+2·pH, logK_p2=logK’_p2+pH
where K′p1=2.2×105, K′p2(cl)=4.1×105, and K′p2(Br)=2.7×106 at 25°C and μ=0.8. As was to be expected from the above equilibrium, K′p1 was idependent of the presence of Cl−, Br−, I−, and EDTA, while K′p1 varied in the presence of Cl−, Br−, and I−. The above relationships were also derived theoretically.
The Reaction between Mercury(II) and Organic Compounds. VIII. Titrimetric Determination of Mercury(II) with o-(2-Thiazolylazo)-2,4-dichlorophenol as a Metallochromic Indicator
Authors: Kai Fumiaki 
Published: July 2006

Abstract
The reaction between mercury(II) and o-(2-thiazolylazo)-2,4-dichlorophenol (TADC) was investigated spectrophotometrically. A mixture containing TADC and a large excess of mercury-(II) showed the absorption maxima in the range of pH 2.3–5.0 at 570 mμ. The composition of the chelate was considered to be as Hg(II) : TADC=1:2. No homologous color was obtained by the reaction between TADC and the other metal ions in the above pH range. Therefore, TADC was suggested as a suitable metallochromic indicator for the direct titrimetric determination of mercury(II) ions with EDTA at pH 3.8–5 (citric acid plus disodium hydrogenphosphate buffer). Sharp color changes were observed from deep violet to orange or to reddish orange at an equivalence point. The titrimetry could be carried out satisfactorily within a range of error of ±0.5% at mercury(II) concentrations of more than 2×10−4m by the present method.
Cobalt(III) and Chromium(III) Complexes with Ethylenediaminemonoacetic Acid
Authors: FuJii Yuki , Kyuno Eishin , Tsuchiya Ryokichi 
Published: July 2006

Abstract
Cobalt(III) and chromium(III) complexes with ethylenediaminemonoacetic acid (EDMA), [Co(edma)2]Cl·2H2O and [Cr(edma)2Cl·3H2]O, (edma: H2NCH2CH2NHCH2COO−), were prepared. The former complex was isolated as two geometrical isomers. From the electronic absorption spectra, the two isomers were assigned to trans and cis forms with respect to the carboxylate oxygen atoms coordinated. Chromium(III) complex was concluded to have the trans form by comparing the IR spectrum with those of the above two isomers of cobalt (III) complexes.