bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Surface Tension of Aqueous Solutions Saturated with Triacetin–Tributyrin Mixtures
Authors: Funasaki Noriaki , Hada Sakae 
Published: July 2006

Abstract
The surface tension of aqueous solutions saturated with triacetin–tributyrin mixtures was measured in order to study the phase equilibria among an adsorbed monolayer (m), an aqueous solution (w), and an oily mixture (1). The variation in the surface tension, γ, of saturated aqueous solutions with an increase in the number of moles, mt, of the added mixtures depended on the mole fractions, x2, of tributyrin in the mixtures; the γ value remained unchanged in the case of x2=0.0027, decreased in the case of x2&gt;0.0027, and increased in the case of x2&lt;0.0027. The results of the theoretical analysis of the γ vs. mt curves gave the mole fractions, x21, of tributyrin in the oily mixtures. The x21 values thus evaluated agreed with those determined gas-chromatographically. It was found that all of the γ vs. x2m, γ vs. x21, and γ vs. x2w curves have a minimum, at which the γ values are identical and at which x2m=x21&gt;2w. The characteristics of these curves were explained thermodynamically on the basis of the assumption that triacetin and tributyrin form a regular mixture in a monolayer as well as in a liquid.
Localized Molecular Orbital Studies of Chemical Reaction. II. Abstraction and Addition Reactions of Triplet Methylene
Authors: Nagase Shigeru , Fueno Takayuki 
Published: July 2006

Abstract
Energy-localized molecular orbitals (LMO) generated from UHF–INDO wave functions have been used for the studies of the mechanistic details of the abstraction and addition reactions of triplet methylene. The UHF LMO mapping procedure which we have previously developed permits a clear understanding of the nature of the chemical bonds to be formed or broken on reaction. Significance of the three-stage mechanism, which should involve the successive β- and α-spin electron delocalizations between reactants and the concomitant spin polarization of the reacting bond, is emphasized. The whole aspects of the reactions are well in accord with the customarily accepted mechanistic schemes.
The Crystal and Molecular Structure of 1-(2-Thiazolylazo)-2-naphthol
Authors: Kurahashi Masayasu 
Published: July 2006

Abstract
The crystal structure of 1-(2-thiazolylazo)-2-naphthol, C13H9N3OS, has been determined from three-dimensional X-ray data collected by counter methods. The crystals are monoclinic with space group P21/a; cell dimensions: a=17.721(1), b=28.366(2), c=4.699(1) Å, β=91.78(1)°, and Z=8. The structure was solved by the symbolic addition procedure and refined by the least-squares method to give an R value of 0.051 for 2150 observed reflections. There are two crystallographically independent molecules in an asymmetric unit; both of the molecules show a generally similar shape and size, but their structural details differ in planarity and distribution of the bond lengths. Both molecules have the azo and hydrazone character, but the equilibrium is shifted toward the azo tautomer.
The γ-Radiolysis of a Cyclohexene–Carbon Dioxide Mixture in the Liquid Phase at −18 °C
Authors: Wojnarovits Laszlo , Hirokami Shun-ichi , Sato Shin 
Published: July 2006

Abstract
The γ-radiolysis of a cyclohexene–carbon dioxide mixture in the liquid phase at −18 °C has been studied. When the mole fraction of carbon dioxide was low, carbon dioxide behaved as an electron scavenger and slightly suppressed the formation of the hydrogen and hydrocarbon products: 2,2′-bicyclohexenyl, cyclohexane, 3-cyclohexylcyclohexene, bicyclohexyl, 1-cyclohexylcyclohexene, and 1,3-cyclohexadiene. Along with this suppression, the formation of cyclohexanol was observed. At the high mole fraction of carbon dioxide, the main products were carbon monoxide and the oxygen atom-addition products: cyclohexene oxide, cyclohexanone, and cyclopentane-carbaldehyde. The material balance for oxygen atoms was good. The formation ratio of the addition products suggests that the precursors of the addition products are the ground-state oxygen atoms. These oxygen atoms are probably produced by the direct radiolysis of carbon dioxide. As the CO2 mole frcation approached unity, the G-values of the addition products and other oxygenated compounds including 2-cyclohexenone and 2-cyclohexenol sharply increased. This suggests that there is another source of oxygen atoms which is suppressed by the presence of cyclohexene. The reactions may be CO2++CO2−→CO+O+CO2 and CO2++cyclohexene→CO2+cyclohexene+. The formation of 2-cyclohexenone and 2-cyclohexenol may be explained in terms of the reaction between the cyclohexenyl radicals and oxygen molecules eventually produced. To support the elucidation of the reaction mechanism, the radiolysis in the solid phase at 77K and the mercury-photosensitized reaction of a nitrous oxide–cyclohexene mixture in the gas phase have also been studied.
Charge-Transfer Bands of the Mixed Molecular Complex, (Anthracene)1−x(Phenanthrene)x(1,2,4,5-Tetracyanobenzene)
Authors: Wright John D , Ohta Toshiaki , Kuroda Haruo 
Published: July 2006

Abstract
A series of crystalline mixed molecular complexes of composition, (anthracene)1−x(phenanthrene)x(TCNB), with 0.17≤x≤0.63, has been prepared from solutions containing mixtures of the three components. A linear relationship is observed between solution and solid composition, and the melting point data and powder X-ray diffraction patterns suggest the formation of a continuous series of mixed molecular complexes of closely related crystal structure. Polarized crystal spectra of these crystals show two charge-transfer bands characteristic of the interaction between anthracene and TCNB and that between phenanthrene and TCNB, respectively. Their intensity ratio is linearly dependent on composition, and constant for different crystals of the same composition. Discussion is given on these results by using the results of semi-empirical SCF-MO-CI calculations on the three-molecule model, anthracene/TCNB/phenanthrene.
The Absorption and Fluorescence Spectra of the Ion-Pairs of 1,2,4,5-Tetracyanobenzene with Several Methyl Substituted Benzenes
Authors: Matsumoto Satoru , Nagakura Saburo , Kobayashi Takayoshi 
Published: July 2006

Abstract
The absorption and fluorescence spectra and the fluorescence decay times were measured at 77 K for the photoirradiation products of the 1,2,4,5-tetracyanobenzene (TCNB) complexes with hexamethylbenzene (HMB), durene, mesitylene, and toluene. The absorption spectra of the photoproducts are similar in shape to that of the TCNB anion and have maxima at 469, 467, 466, and 465 nm for the TCNB complexes with HMB, durene, mesitylene, and toluene, respectively. The fluorescence maximum wavelengths and decay times of the photoproducts are also similar to those of the TCNB anion (505 nm, 19.6 ns for the TCNB-mesitylene system; 505 nm, 20.7 ns for the TCNB-toluene system). The red shift of the absorption maximum and the decrease in the fluorescence decay time by changing the electron donors from toluene to HMB are discussed in terms of ion-pair formation.
Relation between Amounts of Chemisorbed Water and Ammonia on Zinc Oxide
Authors: Nagao Mahiko , Morimoto Tetsuo 
Published: July 2006

Abstract
The adsorption isotherm of NH3 was measured at 25 °C on ZnO surfaces with a controlled amount of surface hydroxyls. It was found that NH3 can be chemisorbed at 25 °C on the dehydroxylated sites of ZnO in a 1 : 1 molecular ratio of adsorbed NH3 to desorbed H2O. H2O can be chemisorbed for prechemisorbed NH3 through exchange reaction to form surface hydroxyls and gaseous NH3. The physisorption of NH3 at 25 °C can take place only on a limited part of ZnO surfaces which were fully hydroxylated or ammoniated.
Copper Nuclear Quadrupole Resonance Spectra of Tris(tetramethylthiourea)copper(I) Tetrafluoroborate and Perchlorate
Authors: Hiyama Yukio , Watanabe Noriyuki , Niki Eiji 
Published: July 2006

Abstract
63Cu, 65Cu NQR spectra of tris(tetramethylthiourea)copper(I) tetrafluoroborate ([Cu(tmtu)3]BF4) and tris(tetramethylthiourea)copper(I) perchlorate ([Cu(tmtu)3]ClO4) have been observed. The resonance frequencies are 27.390 MHz and 25.341 MHz in the BF4 compound, 27.390 MHz and 25.340 MHz in the ClO4 compound (23.0 °C). These results indicate that the crystal structure of [Cu(tmtu)3]ClO4 is very similar to that of [Cu(tmtu)3]BF4 and the copper valence has sp2 hybridization with pπ–dπ bonding. The temperature dependence of 63Cu NQR of [Cu(tmtu)3]BF4 has been studied from −100 to +100 °C. A discontinuous point has been discovered at −11 °C.
Carbon Monoxide Oxidation over Chromium Sesquioxide. I. Nature of Oxygen Adsorbed on Cr2O3
Authors: Kobayashi Masayoshi , Kobayashi Haruo 
Published: July 2006

Abstract
The nature of oxygen species adsorbed on Cr2O3 surface in the temperature range 131–163 °C was studied in detail by application of the transient response method with simultaneous measurements of the electrical conductivity of the catalyst as a p-type semiconductor. The distribution of oxidation power of the adsorbed oxygen species was also measured. The mode of the distribution curve of oxidation power indicates that the oxygen can be classified into two groups which differ in oxidation power as well as in the catalytic activity for the oxidation of CO. From the comparison between the results of the transient response and the oxidation power measurements, it is concluded that the rapidly and slowly adsorbed oxygen groups observed by the transient response method correspond to those of oxygen species of higher and lower oxidation power, respectively. Kinetic analysis of the conductivity response curve caused by the adsorption of oxygen leads to the conclusion that the dissociative adsorption of oxygen associated with electron transfer from the catalyst takes place simultaneously on two different kinds of adsorption sites at substantially different rates.
Carbon Monoxide Oxidation over Chromium Sesquioxide. III. Kinetics of the Reaction
Authors: Kobayashi Masayoshi , Kobayashi Haruo 
Published: July 2006

Abstract
Based on the experimental findings in Parts I and II, mechanisms of carbon monoxide oxidation over α-Cr2O3 were proposed with which the reaction takes place simultaneously through two parallel reaction paths. Overall reaction consists of five elementary steps, and the rate constants of all ellementary stepes were determined from the analysis of appropriate transient response data. The simulation of transient response with these rate constants proved the validity of these mechansims and the results of kinetic analyses.
The Complexing of Indium(III) by Cysteine: Evidence for Sulfurbridged and Protonated Complexes
Authors: Kojima Nakao , Sugiura Yukio , Tanaka Hisashi 
Published: July 2006

Abstract
The complex formation of the cysteine–In(III) system has been investigated by potentiometric titration and by PMR, IR, and UV spectroscopic measurements. The InL, InL2 and InLH species are predominantly formed at the metal concentrations from 0.00025 to 0.0005 M. At higher concentrations of the metal ion (0.0025–0.005 M), however, the InL species is negligible and the InL2, InL3, InL(LH), and In(LH)2 species are predominant. The formation constants calculated with a non-linear, least-squares program were logβ110=14.12, logβ120=27.26, logβ130=32.20, logβ11−1=18.46, logβ12−1=31.78, and logβ12−2=35.74 for InL, InL2 InL3, InLH, InL(LH), and In(LH)2 respectively. The IR and UV spectra revealed that the amino group of the coordinating cysteine was protonated. The [In3L4(OH)(H2O)] complex was isolated.
Spectrophotometric Study of the Zirconium–Pyrocatechol Violet–Tridodecylethylammonium Ternary Complex
Authors: Shijo Yoshio 
Published: July 2006

Abstract
The zirconium–pyrocatechol violet chelate anion is extracted with tridodecylethylammonium bromide in butyl acetate to form a ternary complex. The ternary complex has an absorption maximum at 586 nm in the organic layer. The optimum pH range for the extraction is from 5 to 6. Beer’s law holds for 0.4–9 μg of zirconium in 5 ml of the organic phase. The molar absorptivity of the ternary complex is 3.9×104 mol−1 at 586 nm. The composition of the ternary complex is estimated to be ((Remark: Graphics omitted.).
Glass Formation and Crystallization in Ternary Phosphate Systems Containing Al2O3
Authors: Kishioka Akira , Hayashi Masao , Kinoshita Makio 
Published: July 2006

Abstract
Glass formation and crystallization were investigated in two types of three-component systems, M2O–Al2O3–P2O5 (M=Li, Na, and K) and MO–Al2O3–P2O5 (M=Mg, Ca, and Ba). In the Li2O–Al2O3–P2O5 and MO–Al2O3–P2O5 systems, wide regions of glass formation were found in compositions containing more than 50 mol% of P2O5. In the Na2O–Al2O3–P2O5 and K2O–Al2O3–P2O5 systems, the two peaks in Al2O3 content were found in the regions of glass formation corresponding to about 35 and 65 mol% of P2O5. In the devitrified products of the glasses with 60 and 70 mol% of P2O5, AlPO4, Al(PO3)3, and alkaline earth metaphosphate (in the MO–Al2O3–P2O5 system) were found by X-ray powder diffractometry. The crystalline phases in the samples obtained as mixtures of glass and crystal consisted of AlPO4 in the composition containing 60 mol% of P2O5, while those with a P2O5 composition of 70 mol% consisted of Al(PO3)3. By heating those samples at 700–900 °C, the X-ray diffractions of AlPO4 and Al(PO3)3 were intensified. On the other hand, in the samples with 37.5, 40, and 50 mol% of P2O5, all the crystalline phases consisted of AlPO4, and the intensities of these X-ray diffractions decreased after the samples were heated at 600–700 °C. Thus, there is a marked structural difference between the two peak-regions in the Na2O–Al2O3–P2O5 and K2O–Al2O3–P2O5 systems.
Water-Participation in the Crystalline-State Photodimerization of Cinnamic Acid Derivatives. A New Type of Organic Photoreaction
Authors: Nakanishi Fusae , Nakanishi Hachiro , Tsuchiya Michio , Hasegawa Masaki 
Published: July 2006

Abstract
A new type of organic photoreaction, a water-participation reaction in the crystalline state, has been investigated. The photoirradiation of p-formylcinnamic acid (p-FCA) crystals in the presence of water leads to 4,4′-diformyl-β-truxinic acid (p-FCA dimer) which has one molecule of crystal water. A comparison of the photodimerization carried out in the presence/absence of water revealed the effects of the water molecule on the reaction. That is, the water molecule is incorporated into the p-FCA dimer during the photodimerization process. Furthermore, the water accelerates the reaction rate of photodimerization, leading to the formation of the crystalline dimer, whereas only the water-free amorphous dimer results in the absence of water. In addition, by heating at 100–110 °C, the p-FCA dimer with a water molecule is converted into a water-free crystalline dimer, which is not attainable from a water-free amorphous dimer. The photodimerization of several β-form crystals of cinnamic acid derivatives has been examined from the viewpoint of water-participation: p-nitro, p-chloro, and 3,4-dichlorocinnamic acid were found to photodimerize in the same manner as p-FCA.
Studies of Peptide Antibiotics. XXXIII. Syntheses of Gramicidin S Analogs Containing N-Methyl-l-valine in Place of l-Valine
Authors: Abe Hayao , Sato Kazuki , Kato Tetsuo , Izumiya Nobuo 
Published: July 2006

Abstract
Two analogs of gramicidin S, [1-N-methyl-l-valine]–gramicidin S and [1,1′-di-N-methyl-l-valine]–gramicidin S, were prepared for the purpose of investigating the contribution of NH group of l-valyl residue in gramicidin S to antibacterial activity. They exhibit weak activity as compared with gramicidin S in the antibacterial test toward microorganisms. The optical rotatory dispersions of these analogs and gramicidin S were measured in ethanol and 8 M urea. It was suggested that both analogs have a different molecular conformation from that of gramicidin S, and that the NH group of valyl residues is necessary for stabilizing the conformation to exhibit biological activity.
The Preparation and Reactions of α-Thiocarbonyl Dimethyloxo-sulfonium Ylides
Authors: Yoshida Hiroshi , Yao Terutaka , Ogata Tsuyoshi , Inokawa Saburo 
Published: July 2006

Abstract
α-Thiocarbonyl dimethyloxosulfonium ylides IIIa–e were prepared in moderate yields. The ester-stabilized ylides, IIIa–c, were mixtures of E and Z isomers, and IIIe was Z. The methylation of III with methyl iodide gave S-methylated products, IV, in quantitative yields. The thermal decomposition of IVa and IVe gave I(R=Me) and V respectively in good yields. The treatment of IIIb–e with carbon disulfide afforded 1,2-dithiole-3-thiones VIIIb–e in moderate yields.
The Photochemical Reaction of 1,1,4,4-Tetramethyl-2,3-tetralindione with Hydrogen Donors
Authors: Maruyama Kazuhiro , Takahashi Tomoji 
Published: July 2006

Abstract
The photochemical reaction of 1,1,4,4-tetramethyl-2,3-tetralindione, 1, with hydrogen donors, such as xanthene and aldehyde, in the liquid phase has been investigated. When xanthene was selected as the hydrogen donor, the main products were the “1,2-adduct,” photo-reduced α-keto alcohol, and 9,9′-bixanthenyl. The photolysis of 1 and an aldehyde gave the mixture of the “1,2-adduct” and the “1,4-adduct.” However, in the reaction with isobutyraldehyde another type of “1,2-adduct” was obtained, i.e., a combination product between the semidione radical and the isopropyl radical resulting from the decarbonylation of the isobutyryl radical, together with propene and carbon monoxide. The usual type of “1,2-adduct,” the “1,4-adduct,” and the photo-reduced product (α-keto alcohol) were the minor products in the reaction. It was also confirmed that the original “1,4-adduct” obtained from 1 and acetaldehyde rearranged photochemically to a different type of “1,2-adduct,” but no reverse rearrangement was observed under the present conditions. The mechanisms of the reactions were discussed on the basis of product analysis and the examination of the reaction by means of CIDNP.
Nucleophilic Displacement Catalyzed by Transition Metal. III. Kinetic Investigation of the Cyanation of Iodobenzene Catalyzed by Palladium(II)
Authors: Takagi Kentaro , Okamoto Tadashi , Sakakibara Yasumasa , Ohno Atsuyoshi , Oka Shinzaburo , Hayama Naomi 
Published: July 2006

Abstract
The nucleophilic displacement of iodobenzene with potassium cyanide was carried out in HMPA in the presence of palladium(II) acetate. The reaction obeys the following kinetics;
d[C_6H_5CN]/dt=k[Pd(OAc)_2]_0(M_KCN)^2/3
A reaction scheme composed of two cycles has been proposed: in one cycle Pd0 activates iodobenzene and in the other cycle Pd2+ assists the dissolution of potassium cyanide.
The Synthetic Reactions of Aliphatic Nitro Compounds. XI. The Synthesis of β-Amino-α-hydroxycarboxylic Acids and γ-Aminocarboxylic Acids
Authors: Kaji Eisuke , Igarashi Akira , Zen Shonosuke 
Published: July 2006

Abstract
The O-alkylation of some nitroparaffins, 2-nitropropane, 2-nitrobutane, 1-nitropropane, and phenylnitromethane, with methyl bromoacetate in dipolar aprotic solvent led to α-hydroxy-β-nitrocarboxylates, which were converted into β-amino-α-hydroxycarboxylic acids. Several γ-aminocarboxylic acids were synthesized from the corresponding γ-nitrocarboxylates which were obtained via C-alkylation of the nitroparaffins with methyl β-bromo-propionate.
New Sesquiterpene Lactones of Eremophilane-Type from Ligularia Fauriei (Fr.) Koidz.
Authors: Moriyama Yoshihiko , Takahashi Takeyoshi 
Published: July 2006

Abstract
Two new sesquiterpene lactones of eremophilane-type were isolated from Ligularia Fauriei (Fr.) Koidz., and their structures including absolute stereochemistry were shown to be 8β-hydroxyeremophil-7(11)-ene-12,8α;14β,6α-diolide (1) and eremophil-7(11)-ene-12,8α;14β,6α-diolide (2), respectively. The isolation of the two known lactones, 6β,8β-dihydroxyeremophil-7(11)-en-12,8α-olide (3) and 6β-hydroxyeremophil-7(11)-en-12,8α-olide (4), is also described. The photosensitized autoxidation of the known furanoeremophilan-14β,6α-olide (5) gave 1 and 8β-methoxyeremophil-7(11)-ene-12,8α;14β,6α-diolide (18).
Layered Compounds. XXXVII. Syntheses and Properties of Quadruple-layered Metaparacyclophanes
Authors: Kannen Naoki , Otsubo Tetsuo , Misumi Soichi 
Published: July 2006

Abstract
Six quadruple-layered [2.2]metaparacyclophanes have been synthesized by photo-induced desulfurization or the Hofmann elimination method. Their electronic spectra exhibit stronger transannular electronic iteractions than those of the corresponding triple-layered [2.2]metaparacyclophanes and considerable dependence on the bridge substitution mode of the inside ring. The absorption spectra of the charge transfer compleses of a series of layered metaparacyclophanes and tetracyanoethylene have been studied with regard to the donor characters. It is concluded that the electron release from meta to para ring is significant, while the reverse is less effective.
Studies of the Removal of Oily Soil by Rolling-up in Detergency. II. On Binary Soil Systems Consisting of Oleic Acid and Liquid Paraffin
Authors: Ogino Keizo , Shigemura Ken-ichi 
Published: July 2006

Abstract
The rolling-up mechanism of oily soil from the surface of a polypropylene (PP) sheet in an aqueous solution of sodium dodecylbenzenesulfonate (LAS) was studied by the observation of the contact angle (θ). A binary system consisting of cis-9-octadecenoic acid (oleic acid)–liquid paraffin (Nujol) was used as an example of oily soil. The time required for the removal of the oily soil mixture from the PP sheet by rolling-up became shorter with the increase in the liquid paraffin content of the mixture. The oily soil with binary components was more easily removed from the substrate than a single-component oily soil.
Sulfoxonium Ylide Chemistry. VIII. A Novel Rearrangement of Dimethylsulfoxonium Ylides
Authors: Ide Junya , Hiraoka Tetsuo , Kishida Yukichi 
Published: July 2006

Abstract
Reduction of dimethylsulfoxonium 3-ethoxycarbonyl-1-[1,2-bis(methoxycarbonyl)vinyl]-2-phenylallylide (1) and dimethylsulfoxonium 3-ethoxycarbonyl-1-[2-(ethoxycarbonyl)vinyl]-2-phenylallylide (5) with zinc in acetic acid gave (Z)- and (E)-3-methoxycarbonyl-4-ethoxycarbonyl-5-phenyl-3,5-hexadienoic acid methyl ester (6a and 6b), and (Z)- and (E)-4-ethoxycarbonyl-5-phenyl-3,5-hexadienoic acid ethyl ester (7a and 7b), respectively, whose structures were determined by the NMR spectral data and further chemical transformations. The reaction mechanism of the reductive rearrangement was proposed to proceed through an anion radical to form a four membered intermediate (11), which cleaved to non-conjugated dienes leading to Z and E conjugated products.
Threshold Switching of Violanthrone in a Sandwich-type Cell
Authors: Sadaoka Yoshihiko , Sakai Yoshiro 
Published: July 2006

Abstract
Threshold switching between two impedance states has been observed at room temperature in a sandwich-type cell of violanthrone thin film with the use of silver electrodes. The conductivity of the “on state” is larger than that of the “off state” by a factor of 104.
Absorption Spectrum of the Aggregated Radical Anion of Sulfur Dioxide Produced by γ-Irradiation
Authors: Ito Osamu , Kuwashima Shigeru , Matsuda Minoru 
Published: July 2006

Abstract
By γ-irradiation of sulfur dioxide in 2-methyltetrahydrofuran at −196 °C, blue glassy solution was obtained, although the monomer radical anion of sulfur dioxide was colorless. The absorption spectrum of the blue species was identical with that of the stable radical anion produced by the amalgam reduction of sulfur dioxide, which was attributed to the dimer or trimer radical anion.