bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Distribution and Characterization of 137Cs in Shallow Water Sediments
Authors: Terada Kikuo , Hamano Madoka , Komura Kazuhisa , Matsumoto Ken 
Published: July 2006

Abstract
The distribution and characterization of 137Cs in shallow water sediments are investigated. The concentration of 137Cs in surface sediments which have been collected from the 10–20 m depth of Tsukumo Bay, Noto Peninsula, tends to decrease with an increase in the distance from the inner part of the bay to the outer part. Vertically, 137Cs contents gradually decrease to the 10 cm depth and then steeply decrease beyond this depth, until at the 15 cm depth no activity is observed. A sequential extraction technique with several kinds of extractants has been employed to survey the chemical form of the nuclide in the sediments. 137Cs is completely extracted with an ammonium nitrate solution suggesting that the nuclide is strongly adsorbed in the crystal lattice of some clay minerals and is exchangedly desorbed from the sediment phase by ammonium ions in a high concentration. A core sample has been elutriated in five components of different grain sizes, and the contents of sodium, potassium, and 137Cs have been determined. It has been revealed that a unit amount of the finest component contains about three times as much of the nuclide as that of the coarsest one. On the contrary, the potassium contents slightly decrease with the decrease in the particulate size.
Formation and Identification of Aryldiazenyl Radicals Using the ESR Technique
Authors: Suehiro Tadashi , Masuda Seiichi , Tashiro Takaaki , Nakausa Ryuichi , Taguchi Masamichi , Koike Akemi , Rieker Anton 
Published: July 2006

Abstract
Aryldiazenyl radicals were formed at −104–−116°C by photoirradiation of cyclopropane solutions of 1-aryl-2-(arylthio)diazenes and of l-aryl-3,3-dimethyltriazenes in the presence or absence of olefins, and also by irradiation of cyclopropane solutions of substituted 1,2,3-benzothiadiazoles in the presence of di-t-butyl peroxide. The ESR spectra were analyzed and the hfs constants were assigned by reference to the spectra of methyl, 2H, and 15N-labelled aryldiazenyl radicals and to the results of CINDO calculations. Aryldiazenyl radicals are relatively persistent and the –N=N group rotates about the C–N2 bond axis. The preferred conformations of the radicals were considered.
Base-Catalyzed Hydrolysis of Acetylcholine Chloride in the Presence of Cationic and Nonionic Surfactants
Authors: Nakagaki Masayuki , Yokoyama Shoko 
Published: July 2006

Abstract
The base-catalyzed hydrolysis of acetylcholine chloride (Ach) in the presence of cationic and nonionic surfactants was investigated. The rate of hydrolysis of Ach was determined by following the disappearance of Ach spectrometrically. At a constant pH of 9.0, addition of dodecyltrimethylammonium chloride (DTAC) at concentrations below the critical micelle concentration results in a large decrease in the apparent rate constant for the hydrolysis of Ach, kapp. The plot of kapp against the concentration ratio of DTAC to Ach (CDTAC/[D]0) gives a break point at CDTAC/[D]0=1. This is considered to be due to the formation of 1 : 1 complex between Ach and DTAC. In the presence of heptaoxyethylene dodecyl ether (HED)–DTAC mixed micelles, kapp decreases with the mole fraction of DTAC, in contradistinction to the usually presupposed electrostatic effect. This is because Ach molecule penetrates into the micellar phase and is shielded from the attack by OH− for hydrolysis. The decrease of kapp has been successfully interpreted on the basis of the data on the distribution of Ach between the micellar and aqueous phases.
Photochemical Reactions of N-Methyl-1,2-naphthalenedicarboximide with Alkenes. Preferential Naphthazepinedione Formation
Authors: Kubo Yasuo , Toda Rie , Yamane Kengo , Araki Takeo 
Published: July 2006

Abstract
Irradiation of benzene solutions of N-methyl-1,2-naphthalenedicarboximide (1) in the presence of alkenes (2a,b,d–i) gave two regio-isomers of naphthazepinediones (3a,b,d–i and 4a,b,d–i). Stereospecificity of the naphthazepinedione formation was observed in the reaction with cis- and trans-2-butene (2a and 2b). Naphthazepinediones (3j and 4j) produced by the irradiation of 1 with ethyl vinyl ether (2j) underwent secondary photoreactions to give 7 and 8, respectively. On the other hand, irradiation of 1 with 2,3-dimethyl-2-butene (2k) resulted in the formation of oxetanes (13a,b) and 1 : 1-adducts of 1 and 2k at the carbonyl groups of 1 (14 and 15a,b). Irradiation of 1 with cis-stilbene (2l) afforded oxetanes (22a,b) and fragmentation products of oxetanes (23a,b, and 24). Stern-Volmer slopes (kqτ) obtained from quenching of fluorescence of 1 by alkenes (2a–e,k) correlated to some extent with relative rates for disappearance of 1 in the reaction. Preferential formation of the naphthazepinedione was rationalized by the nature of the excited singlet state of 1 compared with those of other N-methylarenedicarboximides.
Synthesis of ara-Cadeguomycin. 2-Amino-3,4-dihydro-4-oxo-7-(β-d-arabinofuranosyl)-7H-pyrrolo[2,3-d]pyrimidine-5-carboxylic Acid
Authors: Okamoto Kaoru , Kondo Tadao , Goto Toshio 
Published: July 2006

Abstract
2-Amino-3,4-dihydro-4-oxo-7-(β-d-arabinofuranosyl)-7H-pyrrolo[2,3-d]pyrimidine-5-carboxylic acid, an analogue of cadeguomycin, has been synthesized via glycosylation of 3-methoxymethyl-5-methyl-2-methylthio7H-pyrrolo[2,3-d]pyrimidin-4(3H)-one with 2,3,5-tri-O-benzyl-d-arabinofuranosyl chloride.
Crystal Structue and Absolute Configuration of a New cis-Fused Caryophyllene Derivative. Naematlin 3-p-Bromobenzoate
Authors: Tsuboyama Sei , Sakurai Tosio , Tsuboyama Kaoru , Doi Kozo 
Published: July 2006

Abstract
The molecular structure of naematolin 3-p-bromobenzoate has been determined by X-ray diffraction analysis. Unlike known caryophyllene derivatives isolated so far, the stereochemistry of the ring juncture is cis (1S,9S) form. The absolute configurations of five chiral centers of this compound are 1S,2S,3R,6R, and 9S, and the geometry of endocyclic double bond is E mode. This is the first example of a cis-fused 1S,9S-caryophyllane sesquiterpenoids confirmed by X-ray structure determination. Crystal data and the final R factor are: Mr=491.36, orthorhombic, space group P212121, a=10.650(2), b=20.650(6), c=10.526(2) Å, U=2315(1) Å3, Z=4, Dc=1.410 Mg m−3, μ=1.791 mm−1, R=0.084 for 1666 observed unique reflections.
Base-Catalyzed Hydrolysis of Acetylcholine Chloride in the Presence of Anionic and Nonionic Surfactants
Authors: Nakagaki Masayuki , Yokoyama Shoko 
Published: July 2006

Abstract
Base-catalyzed hydrolysis of acetylcholine chloride (Ach) in the presence of anionic and nonionic surfactants was investigated. The rate of hydrolysis was determined by measuring the rate of disappearance of Ach with a spectrophotometer. At a constant pH of 9.0, addition of heptaethylene glycol dodecyl ether (HED) at concentrations above the critical micelle concentration (cmc) results in a slight increase in the apparent rate, υ, which is expressed by two reaction rates, υf and υm, in the aqueous and micellar phases, respectively. The increase in the apparent rate is due to increase in υm. In the presence of sodium dodecyl sulfate (SDS), the apparent rate constant, kapp, is approximately constant at concentrations below the cmc, and kapp decreases above the cmc. In the presence of SDS–HED mixed micelles, kapp decreases with the mole fraction of SDS. In these cases, the decrease in the apparent rate is due to the decrease in both υf and υm. These two kapp decreases are due, respectively, to the decrease in Ach in the aqueous phase and the electrostatic repulsion between OH− and DS− at the micelle surface in conformity with the Gouy-Chapman theory.
The Formal Potentials of Quinones0⁄- and Quinones-⁄2- in an Aqueous Solution
Authors: Suga Kosaku , Aoyagui Shigeru 
Published: July 2006

Abstract
Cyclic voltammograms of p-benzoquinone and its methyl derivatives are measured in a strongly alkaline aqueous solution. All of them have shown one reversible or quasi-reversible wave corresponding to the reduction of the quinones. Except for the 2,3,5,6-tetramethyl-p-benzoquinone (duroquinone), they have all also shown one or two additional small waves corresponding to the reduction of the OH− adducts of the quinones. Their main waves can reasonably be explained by the calculated values of E1° and E2°, which have been determined by the two-electron reduction potential and the several equilibrium constants of the quinones. The differences in the E1° and E2° values for these quiones are very small (0.007–0.046 V) in contrast to those in an aprotic solvent.
The Microwave Spectrum of Ethyl Isoselenocyanate
Authors: Sakaizumi Takeshi , Iida Kazuyuki , Ohashi Osamu , Yamaguchi Ichiro 
Published: July 2006

Abstract
The microwave spectra of two isotopic species (80Se and 78Se) of ethyl isoselenocyanate were measured in the frequency region of 10–28 GHz. Only a-type R-branch transitions in the ground vibrational state were identified. The rotational constants in MHz were obtained; A=15140±23, B=1090.443±0.016, and C=1029.261±0.016 for 80Se species and A=15112±28, B=1099.865±0.012, and C=1037.745±0.012 for 78Se species. The plausible structure of ethyl isoselenocyanate has deduced from the observed rotational constants to be the synperiplanar form with a plane of symmetry.
Production of Carbon Monoxide by Direct Thermal Splitting of Carbon Dioxide at High Temperature
Authors: Nigara Yutaka , Cales Bernard 
Published: July 2006

Abstract
The direct thermal decomposition of carbon dioxide CO2 to produce carbon monoxide CO have been studied as a mean of conversion and storage of a thermal energy, such as the solar heat, into a gaseous fuel. The process under investigation consists to displace the dissociation equilibrium of carbon dioxide by a selective pumping of oxygen at high temperature through a semipermeable membrane. Large amounts of carbon monoxide have been produced after the extraction of the oxygen arising from the CO2 dissociation with the aid of a membrane made of calcia-stabilized zirconia. The variations of the flow of CO evolved from the reactor vs. temperature and oxygen partial pressure are in good agreement with the theoretical variations that may be deduced from the general equations of electrochemical transport in stabilized zirconia. Thereby, the efficiency of this process appears to be directly limited by the low oxygen permeation rate through the material used as oxygen selective membrane.
Synthesis, Ion-Exchange Properties and Analytical Applications of Tin(IV) Tungstovanadophosphate
Authors: Nabi Syed Ashfaq , Siddiqui Weqar Ahmad 
Published: July 2006

Abstract
Samples of tin(IV) tungstovanadophosphate have been synthesized under varying conditions and their ion-exchange properties are studied. Among the various samples of tin(IV) tungstovanadophosphate, sample TTVP7R is chosen for detailed study and its ion-exchange properties are compared with sample TTVP7. Both the compounds are synthesized in excess of acid, i.e. at pH less than zero. Sample TTVP7 is synthesized by adding 0.025 mol dm−3 sodium metavanadate, 0.025 mol dm−3 sodium tungstate and 1.0 mol dm−3 phosphoric acid to 0.1 mol dm−3 tin(IV) chloride in the volume ratio of 1:1:1:1 at pH=0. Sample TTVP7R was prepared by refluxing the precipitate of sample TTVP7 in the reaction mixture. The chemical and thermal stabilities of this material have been determined. The reproducibility of the material is also checked. Distribution coefficients for numerous metal ions in formic acid-sodium formate buffer systems of different pH were determined. The utility of the material has been demonstrated by achieving a number of binary and ternary separations on its small columns.
Electrolytic Reduction of 1-Methylsulfinyl-1-methylthio-1-alkenes at Mercury Electrode in Nonaqueous Media
Authors: Kunugi Akira , Abe Kyo , Hagi Toshio , Hirai Taketsugu 
Published: July 2006

Abstract
In the electrolytic reduction of organic sulfur compounds of general formular (Remark: Graphics omitted.), the substrates with R=aryl are much easier to reduce than those with R=alkyl, and the former substrates afford the desulfinylated compounds, E-isomers of RCH=CH(SMe), in good yields, but the later substrates do not give the corresponding desulfinylated compounds.
The Crystal Structure of Bis(2,2′-bipyridyl)palladium(II) Picrate [Pd(bpy)2](pic)2. A Novel “Bow” Distortion
Authors: Maeda Sh\={u}ichi , Nishida Yuzo , Okawa Hisashi , Kida Sigeo 
Published: July 2006

Abstract
The title complex crystallized in the triclinic space group P\barl with a=8.228(2), b=13.493(2), c=7.753(1)Å; α=96.96(1), β=106.16(1), γ=99.99(1)°; Z=1. The structure was solved by the heavy-atom method and refined by the block-diagonal least-squares method to R=0.0366. It is found that picrate ions above and below the [pd(bpy)2]2+cation stack with the bpy molecules and that this stacking leads to a novel bow distortion of the cation.
Di-n-octyl Phenyl Phosphonate: A Plasticizer of Poly(vinyl chloride) Matrix Membrane Electrodes Behaving As a Li+-selective Agent
Authors: Hiratani Kazuhisa , Okada Tatsuhiro , Sugihara Hideki 
Published: July 2006

Abstract
PVC matrix membrane electrodes, which are composed of dioctyl phenylphosphonate (DOPP) as a plasticizer and potassium tetrakis(4-chlorophenyl)borate (KTCPB) as a lipophilic anionic additive, without any other ionophore, exhibit appreciable Li+-selectivity. The electrode has selectivity coefficients (logkLiMPot for Li+ over Na+ up to −1.2, over K+ up to −1.8, over Mg2+ up to −1.8, and over Ca2+ up to −1.2. The detection limit for Li+ was about 5.0×10−5 mol dm−3.
Palladium(0)-Catalyzed Coupling Reaction of Isoprene Bromohydrin with Aromatic Organolithium Reagents
Authors: Araki Shuki , Ohmura Masayuki , Butsugan Yasuo 
Published: July 2006

Abstract
Palladium(0)-catalyzed reaction of isoprene bromohydrin with aromatic organolithium reagents selectively gave good yields of coupling products without rearrangement.
Titrations by Temperature Difference Electrode: Entropy Titrations
Authors: Ikeshoji Tamio 
Published: July 2006

Abstract
A new type of potential-difference titration which has a relation with the entropy change of a reaction in a titrated solution was demonstrated using a Hg2+–EDTA reaction on an Hg electrode. The potential difference between two identical electrodes, one kept at a different temperature from that of the solution, was monitored during titration. This difference changed from a minimum to a maximum at the equivalent point.
Conformational Changes of 1,2,3-Triselena- and 1,2,3-Trithia[3]( 1,1′)ruthenocenophane
Authors: Akabori Sadatoshi , Kumagai Takeshi , Sato Masaru 
Published: July 2006

Abstract
1,2,3-Triselena[3](1,1′)rutnenocenophane was obtained by the reaction of 1,1′-dilithioruthenocene with selenium powder in 22% yield. The energy barriers of the bridge reversal inversion of 1,2,3-triselena- and 1,2,3-trithia[3](1,1′)ruthenocenophane are 78.8 and 91.5 kJ mol−1, respectively.
Reaction of Nitromethane with Aryl Isocyanates in the Presence of Triethylamine. A Formation of 1,3-Diaryl-5-(hydroxyimino)imidazolidine-2,4-diones
Authors: Shimizu Tomio , Hayashi Yoshiyuki , Teramura Kazuhiro 
Published: July 2006

Abstract
1,3-Diaryl-5-(hydroxyimino)imidazolidine-2,4-diones were obtained from the reactions of nitromethane with several aryl isocyanates in the presence of a trace amount of triethylamine and their structures were established from spectroscopic evidence and their chemical behavior.
Chemistry of 1,2-Thiaphosphole 2-Sulfides. III. Cycloaddition Reactions with Some Acetylenic Dienophiles and Generation of Phosphorin 1-Sulfides
Authors: Tanaka Hideyuki , Motoki Shinichi 
Published: July 2006

Abstract
1,2-Thiaphosphole 2-sulfides reacted with dimethyl acetylenedicarboxylate or phenylacetylene to afford 1-phosphabarrelene 1-sulfides (1-phosphabicyclo[2.2.2]octa-2,5,7-triene 1-sulfides) via phosphorin 1-sulfides.
Oxidation Reactions of a System Composed of Chloro(5,10,15,20-tetraphenylporphyrinato)cobalt(III) and Its π Cation Radical with Phenols
Authors: Kohno Masahiro 
Published: July 2006

Abstract
The reactions of a system composed of chloro(5,10,15,20-tetraphenylporphyrinato)cobalt(III), [CoIIICl(tpp)], and its π cation radical coordinating axially two chloride anions, [CoIII(tpp)+·]Cl2, with several phenols were investigated by using ESR and optical absorption spectroscopy. The phenols were oxidized to phenoxyl radicals. The phenols investigated were classified into two groups after taking into account the differences in the reaction activities and their redox potentials, the phenols mainly reacting with [CoIII(tpp)+·]Cl2 and those reacting with both [CoIIICl(tpp)] and [CoIII(tpp)+·]Cl2. The oxidation reactions of phenols with [CoIII(tpp)+·]Cl2 were the second-order. A linear relationship between the rate constants of oxidation and the redox potentials of phenols was recognized. Active species in the reactions were determined to be composed of a chlorine radical which originates from axial ligands of [CoIIICl(tpp)] and [CoIII(tpp)+·]Cl2, and the porphyrin ligand of [CoIII(tpp)+·]Cl2 itself. A possible mechanism for the oxidation reactions is proposed. Finally, the reaction scheme of cobalt porphyrin, ([CoII(tpp)], [CoIIICl(tpp)], and [CoIII(tpp)+·]Cl2) with phenols is compared with oxidation reactions of phenols with horseradish peroxidase.
Electrochemical Properties of Electropolymerized Poly(1-pyrenamine) Films
Authors: Oyama Noboru , Hirabayashi Kazuhiko , Ohsaka Takeo 
Published: July 2006

Abstract
The electropolymerization of 1-pyrenamine (PA) in an acetonitrile solution led to the polymeric film formation on electrode surfaces. The chemical, spectroscopic, electrical and electrochemical characterization of the resulting poly(1-pyrenamine) (PPA) films was carried out. The number-average molecular weight of the PPA film, measured by gel permeation chromatography, was 1.8×103, corresponding to the degree of the polymerization of ca. 8. The PPA films were polymer-anion composites which contained ca. 0.3 anions (e.g., BF4−) per repeating aromatic unit, which is considered to be composed of three PA molecules. The oxidized form of the PPA film displayed the ESR response. The g factor was 2.0082 and the concentration of radical in the PPA film was determined to be 4.8×1019 e−g−1. The conductivities of the PPA films in the dry state at 300 K were in the range 10−11–10−10 S cm−1. The PPA film was electroactive in an aqueous solution as well as in a non-aqueous solution. The cyclic voltammetric responses depended on pH of aqueous solutions and supporting electrolyte in non-aqueous solutions. The thickness(φ) of the PPA film and the surface concentration(Γ) of the electroactive site in the PPA film were proportional to the amount (Q) of the charge passed during the electrolysis (when Q&lt;ca. 120 mC cm−2). The volume concentrations of the electroactive site were 9.7×10−4 and 1.7×10−3 mol cm−3 for the PPA films prepared in the NaClO4 and TBABF4 (tetrabutylammonium tetrafluoroborate) electrolytes, respectively. From the normal pulse voltammetric, potential-step chronoamperometric and potential-step chronocoulometric experiments of the PPA films in a 0.2 M NaClO4 aqueous solution (pH 1.0), the effective apparent diffusion coefficient (Dapp) for the diffusion-like charge transport within the PPA films, and the standard rate constant (k°) and anodic transfer coefficient (αa) of the heterogeneous electron-transfer reaction between the In2O3 electrode and the electroactive site in the PPA film were estimated to be (1.5±0.5)×10−10 cm2 s−1, (1.9±0.4)×10−5 cm s−1 and 0.67±0.03, respectively.
Critical Behavior of the Correlation Function of Fluids Composed of Polar Diatomic Molecules
Authors: Ohba Masaharu , Arakawa Kiyoshi 
Published: July 2006

Abstract
A critical behavior of fluids composed of polar diatomic molecules is studied by the use of the Ornstein–Zernike (OZ) theory of critical phenomena extended to the interaction site model. Firstly, the asymptotic forms of the atom–atom direct correlation functions cαγ(r) for the polar fluids at large separation are obtained, which are valid off the critical point. Then, the OZ hypothesis that the asymptotic forms of cαγ(r) do not change near and at the critical point is examined, and the critical behavior of the total correlation function is investigated. It is found to be completely analogous to the case of simple fluids. The relation between the OZ hypothesis and some integral equation theories is also discussed.
Mössbauer Spectroscopic Studies of Tin(IV) Halide Adducts with Ruthenocene and with [2]Ferrocenophanes
Authors: Watanabe Masanobu , Motoyama Izumi , Sano Hirotoshi 
Published: July 2006

Abstract
Adducts of tin(IV) halide with [2]ferrocenophane were prepared by treating SnX4 (X=Cl or Br) with [2]ferrocenophane in hexane. The adducts were studied by means of 57Fe- and 119Sn-Mössbauer spectroscopy and other physicochemical measurements. Anomalously large quadrupole splittings (3.49 mm s−1 for [2]ferrocenophane–1.5SnCl4 adduct and 3.47 mm s−1 for [2]ferrocenophane–1.5SnBr4 adduct, both at 78 K) found in the 57Fe-Mössbauer spectroscopy and organotin(IV) species (e.g., isomer shift value, 2.14 mm s−1 for the [2]ferrocenophane–1.5SnCl4 adduct and 2.10 mm s−1 for the [2]ferrocenophane–1.5SnBr4 adduct, both at 78 K) found from the 119Sn-Mössbauer spectroscopy suggest that a direct chemical bonding between Fe and Sn atoms is formed in the [2]ferrocenophane adducts, as the Ru–Sn bonding in the ruthenocene–1.5SnCl4 adduct (isomer shift value, 2.08 mm s−1 at 78 K).
(Remark: Graphics omitted.)
Paramagnetic Shifts of DMF and DMA by Uranium(V)
Authors: Harazono Toshie , Fukutomi Hiroshi 
Published: July 2006

Abstract
Paramagnetic shifts of DMF (N,N-dimethylformamide) and DMA (N,N-dimethylacetamide) induced by U(V) were studied by the 1H and 13C NMR spectroscopy. It was found that the 1H and 13C NMR signals of bulk DMF and DMA exhibited the paramagnetic shifts to the higher field by U(V). Positive pseudocontact shift and negative contact shift for both DMF and DMA are discussed on the basis of the electronic structure of U(V) complexes. The values of magnetic susceptibilities of U(V) complexes are also presented.
Magnetic Circular Dichroism Spectra of Cobalt(III) Complexes in the Second d–d Absorption Band Region
Authors: Matsuoka Nobuko 
Published: July 2006

Abstract
The MCD spectra of seventeen cobalt(III) complexes were measured in the visible and near-ultraviolet regions. Their behavior in the second d–d absorption band region were compared with those of the [Co(ox)x(gly)y(en)z] series comprising sixteen complexes (x, y, z=0, 1, 2, 3; and x+y+z=3), in which a positive band had been observed on the lower-energy side of the main negative band in this region. For the present work, the positive band was found in [Co(tn)3]3+, cis-[Co(ox)2(NH3)2]−, cis-[Co(OH2)2(en)2]+, trans-[Co(β-ala)2(en)]+, mer- and fac-[Co(picol)3] (picol=picolinate(1–)), and [Co(acac)3]. It is pointed out that all the complexes exhibiting a positive band were the tris(chelate) or cis-bis(chelate) types. Therefore the origin of this band is discussed in terms of the arrangement of two or three chelate rings. A positive band was not observed for complexes containing a CO32− ligand, even if they were a tris(chelate) or cis-bis(chelate) type. This is explained from a structural basis. The two complexes which had a split second d–d absorption band, mer-trans(NH3)-[CoCO3(gly)(NH3)2] and [CoCO3(picol)(NH3)2], showed two negative bands in the corresponding regions to both component absorption bands, in each complex.