bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on the Solvent Extraction of Metal Perchlorates III. Extraction Equilibria of Alkaline Earth Ions with Trioctylphosphine Oxide as Perchlorate and Thiocyanate
Authors: Kusakabe Satoshi , Sekine Tatsuya 
Published: July 2006

Abstract
Solvent extraction of alkaline earth metal ions in 1 mol dm−3 sodium perchlorate or thiocyanate aqueous solution with trioctylphosphine oxide (TOPO) in hexane was studied at 25 °C. The extraction in both systems improved in the order: beryllium(II)&gt;calcium(II)&gt;strontium(II)\simeqmagnesium(II)\simeqbarium(II). When the TOPO concentration was the same, the extraction of beryllium or calcium thiocyanate was better than that of the perchlorate, that of magnesium or strontium thiocyanate was nearly similar to that of the perchlorate, while barium perchlorate was extracted better than its thiocyanate. From these results it was concluded that these five perchlorates and strontium and barium thiocyanates were extracted as ion-pairs, [M(topo)4]2+(X−)2, (X−=ClO4− or SCN−), while beryllium thiocyanate was extracted as solvates of noncharged complexes, M(SCN)2(topo)n, (n=2 and 3), and that magnesium and calcium thiocyanates in the organic phase (n=3 and 4) should have both ionic and coordinative properties. The poor extraction of magnesium salts was assumed to be due to their strong hydration.
Determination of Germanium by Atomic Absorption Spectrometry Following Volatile Hydride Generation
Authors: Jin Kazuo , Terada Hiroaki , Taga Mitsuhiko 
Published: July 2006

Abstract
A sensitive technique for determination of germanium was investigated by atomic absorption spectrometry following volatile hydride generation. Of the three types of hydride generator and atomizer systems tested, direct transfer of the generated hydride into nitrogen-hydrogen flame for atomization was found to be suitable. The sensitivity was enhanced more than 40–60% in phosphoric acid medium as compared to hydrochloric acid, malic acid, or tartaric acid media. Interference of nickel(II), gold(III), and cobalt(II) in hydrochloric acid medium was reduced by adding ethylenediaminetetraacetate as a masking reagent or replacing the acid medium by malic acid. Detection limit and relative standard deviation of ten determinations of 0.5 μg germanium(IV) in 20 ml of 0.20 M phosphoric acid were 7 ng (S/N=2) and 4.3%, respectively, with 3 ml of 8 w/v % sodium tetrahydroborate solution. The method was applied to the determination of germanium in standard rocks, concentrations of germanium in JB-1 and JG-1 being evaluated as 1.31 and 1.32 ppm, respectively.
Preparation and Spectroscopic Studies of Cobalt(III) Complexes Containing Optically Active Seven-membered Chelate Ligands
Authors: Kojima Masaaki , Morita Ken’ichi , Fujita Junnosuke 
Published: July 2006

Abstract
New cobalt(III) complexes of the types, trans-[CoCl2L2]+, [Co(NH3)4L]3+, cis-[Co(NH3)2L2]3+, and [Co(en)2L]3+, where L denotes a seven-membered chelate diamine ligand, (R)-2-methyl-1,4-butanediamine or meso- and (R or S)-2,5-hexanediamine, have been prepared. The dichloro complexes decompose gradually even in the solid state, and rapidly in methanol. The ammine and ethylenediamine complexes are stable in acidic water, but decompose gradually in neutral water. The absorption and circular dichroism spectra of all the complexes have been recorded in aqueous or acetone solutions. The circular dichroism spectra in the first absorption band region are changed by the addition of sulfate ions, and the variation has been discussed in terms of the structure of isomers and the conformational instability of the seven-membered chelate rings.
Pyrolytic Sulfurization Gas Chromatography. IX. Determination of the Atomic Ratio between C, H, O, N, Cl, Br, and I in an Organic Halogen Compound
Authors: Hara Tadashi , Fujinaga Kaoru , Okui Fujio 
Published: July 2006

Abstract
The atomic ratio between C, H, O, N, Cl, Br, and I in an organic halogen compound was obtained satisfactorily by gas chromatography and ion chromatography. At first the atomic ratio between C, H, O, and N was determined simultaneously by PSGC and then the atomic ratio between a halogen atom and C, H, O, and N was obtained by estimating the amount of a halogen atom in the reaction residue and by calculating the weight percent in Eq. 4 by use of a correction factor and peak areas in gas and ion chromatograms.
Formation of Anatase Precipitates Containing Fe(III) by the Air Oxidation at 95 °C of Strongly Acidic Solutions
Authors: Kiyama Masao , Takada Toshio 
Published: July 2006

Abstract
Strongly acidic titanium(II)) chloride solutions containing iron (II) sulfate were subjected to oxidation with air at 95 °C. The products consist of spheres, 0.5–1.0 μm in size, each composed of extremely fine particles, 100–150 Å in size. Fe(III) is incorporated up to about 6% of the total metal ions in the product, in spite of the strongly acidic solution. The products, containing H2O and SO42− besides Fe(III), are dehydrated in the temperature range 100–400 °C and the sulfate decomposition begins at about 750 °C in air. The SO42− in the products can be easily removed by washing at room temperature with NaOH solution. No marked differences can be detected in color, magnetic properties, or in growth of the extremely fine particles before and after the dehydration by heat treatment at 500 °C; a change in such physical properties begins to occur at 550 °C. It is concluded that the Fe(III) in the product is interposed between the extremely fine particles, whereas the H2O and SO42− are adsorbed in the spherical poly crystal line particles formed with oxo and hydroxo combination of the extremely fine particles.
The Separation by Means of the Zone-melting Technique and the Spectrofluorometric Determination of Trace Amounts of Anthracene in Phenanthrene
Authors: Furusawa Motohisa , Tachibana Masaki 
Published: July 2006

Abstract
Since ordinarily available phenanthrene contains interfering impurities, such as phenanthrenequinone and fluoranthene, it is difficult to determine anthracene by spectrofluorimetry directly. Trace amounts of anthracene in phenanthrene can, however, be selectively separated from the interfering impurities by means of the zone-melting technique, for the distribution coefficient of anthracene in phenanthrene is greater than unity. The anthracene thus separated is spectrofluorometrically measured using xylene as the solvent. The determination limit of anthracene is 0.05 ppm. In a glass tube with an i.d. of 4 mm, 4.0 g of the sample was charged to a length of about 27 cm, and then the zone-pass was repeated 20 times. The molten zones were set to travel at a speed of 100 mm/h under constant stirring. Exactly 2.5 g of the zone-molten sample was cut out and dissolved in 50 ml of xylene. The fluorescence intensity of the solution was measured at 403 nm with excitation at 378 nm. The recovery of anthracene was 95%, with a coefficient of variation of 0.6%. The incompleteness of the recovery was corrected for.
Optical Resolution of rac-5,5,7,12,12,14-Hexamethyl-1,4,8,11-tetraazacyclotetradecane (L), Circular Dichroism Spectra of Ni(II) Complexes with the Active Ligand, and the Absolute Configuration of (−)589-[{Ni(SS-L)}2(d-tart)(H2O)](ClO4)2·2H2O as Determined by the X-Ray Analysis
Authors: Ito Haruko , Fujita Junnosuke , Toriumi Koshiro , Ito Tasuku 
Published: July 2006

Abstract
The title ligand (L) has been resolved through its d-tartrato-nickel(II) complex. The X-ray analysis shows that the less-soluble (−)589-diastereomer has a dimer structure with the folded macrocycles, [{NiL}2(d-tart)(H2O)](ClO4)2·2H2O, and that the chiral carbon atoms have the absolute configuration of S. Axial methyl groups of geminal dimethyl pairs of each nickel (II) complex in the dimer provide stereoselective environment for the coordination site of the d-tartrate ion. Stereospecific hydrogen-bonds between a secondary amine group of the macrocyclic ligand or coordinated water and hydroxyl or carboxyl oxygens of the d-tartrate ion play also an important role in the optical resolution. Pairs of enantiomers of the free ligand and three isomers of the four-coordinate nickel(II) complex have been isolated. Circular dichroism spectra of various four- and six-coordinate complexes with the optically active ligand have been described.
Synthesis and Structures of Steroidal Oxathiolanes
Authors: Shafiullah  , Ali Hasrat , Ogura Haruo , Takayanagi Hiroaki 
Published: July 2006

Abstract
Synthesis of isomeric oxathiolanes from 6-oxosteroids is described. Configurations at spirocyclic carbon in these compounds have been established on the basis of CD and NMR spectra with the use of shift reagent [Eu(dpm)3].
Intramolecular Interactions between a Group Bearing n-Electrons and a CH2–X Where X is an Electronegative Group
Authors: Izumi Giichi , Yamamoto Gaku , Oki Michinori 
Published: July 2006

Abstract
Conformational equilibrium of 9-(2-acyloxyethyl)-1,4-dimethoxytriptycenes in chloroform-d suggests that the stability of the ±sc conformation increases as the electronegativity of the acyl group increases. The results together with other pertinent data are discussed from the stand point that there is an attractive interaction between the acyloxymethyl and the methoxyl groups in proximity. Reflecting its high ionization potential, the chloro group in 1-position showed no stabilization of the ±sc conformation, although mass spectra and some chemical properties indicate that there is an interaction between the chloro group and highly electronegative CH2X group. A possible correlation of these results with the incipient transition state for SN2 reactions is suggested.
A New Method for Protein Sequence Analysis Using Edman-degradation, Field-desorption Mass Spectrometry and Computer Calculation. Sequence Determination of the N-Terminal BrCN Fragment of Streptomyces erythraeus Lysozyme
Authors: Shimonishi Yasutsugu , Hong Yeong-Man , Katakuse Itsuo , Hara Saburo 
Published: July 2006

Abstract
A new method is described for protein sequence analysis. The principle is realized as follows: 1) determination by field-desorption mass spectrometry of the molecular weights of the constituents in peptide mixtures prepared from a polypeptide or protein by specific cleavage methods, 2) quantitation of the 3-phenyl-2-thiohydantoin derivatives of amino acids liberated successively from the constituent peptides in 1) by Edman-degradation, and 3) determination of amino acid sequences with a computer from the data obtained in 1) and 2). The method was applied to sequence determination of a polypeptide of unknown structure, the N-terminal BrCN fragment of Streptomyces erythraeus lysozyme.
Reaction of Hexafluoropropene Dimers with Organomagnesium and -lithium Reagents
Authors: Ishikawa Nobuo , Butler Sigmund , Maruta Masamichi 
Published: July 2006

Abstract
Nucleophilic reactions of F-2-methyl-2-pentene (1) and (E)-F-4-methyl-2-pentene (2), the dinners of hexafluoropropene, with organomagnesium and -lithium reagents were investigated. The reaction of 1 proceeded readily, giving two alkyl- or aryl-substituted polyfluoroalkenes which resulted from α- and γ-fluorine elimination, respectively. Only phenyllithium reacted with 2, giving also α- and γ-fluorine eliminated phenylpolyfluoroalkenes. The reaction mechanism of γ-elimination was postulated in relation to the electropositive property of the organo group and to Mg–F or Li–F bond formation.
Spectral Behavior of 3,6-Substituted Aminoacridine Dyes with Emphasis on the Perturbation of the Exonuclear Amino Groups
Authors: Yamaoka Kiwamu , Noji Sumihare , Yoshida Mamoru 
Published: July 2006

Abstract
The optical absorption spectra of several derivatives of Proflavine (PF) and Coriphosphine O (CP) were measured in aqueous solutions at 25 °C. The effect of the perturbation of one or both of the exonuclear amino groups on the spectral behavior was studied in order to explore the relationship between the spectra and the chemical structures of the symmetric 3,6-disubstituted acridine dyes which can bind to various polyelectrolytes, often showing metachromasy. The metachromatic spectra of the complexes between 3,6-diaminoacridine dyes and polyanions were reproduced reasonably well when one of the two amino groups of PF was converted to an acylamino group. A similar result was observed when the amino group of CP was acetylated. In these cases, the spectra show two absorption bands of nearly equal intensity on both sides of the single peak of PF and CP in the visible region. These results are indicative of the close similarity in chemical structures between the monacylamino PF and the PF bound to the electron-rich sites of polyanions.
One-step Oxidation of Olefins into α-Phenylseleno Carbonyl Compounds
Authors: Shimizu Makoto , Kuwajima Isao 
Published: July 2006

Abstract
Oxidation of olefins has been examined with the following three types of reagents; (i) (C6H5Se)2–Br2–(Bu3Sn)2O, (ii) (C6H5Se)2–t-BuOOH, and (iii) (C6H6Se)2–(C6H5SeO)2O, and the corresponding α-phenylseleno carbonyl compounds have been obtained directly from the olefins.
The Characterization of a Novel Metathesis Catalyst, β-Titanium Oxide-supported Molybdenum Oxide
Authors: Tanaka Katsumi , Miyahara Koshiro , Tanaka Ken-ichi 
Published: July 2006

Abstract
The results of the X-ray photoelectron spectroscopy of a novel metathesis catalyst, MoOx/β-TiO2, are discussed with reference to its catalytic behavior. It is concluded that the active center for the metathesis reaction of olefin is the molybdenum ion with an oxidation higher than +4 on the average, and that the hydrogen scrambling of olefin during the metathesis is caused by the OH group on the TiO2 surface. During the preparation of this catalyst, the decomposition of titanic acid to TiO2 is found to be accelerated by MoO3; a similar thing can be seen of the reduction of MoO3 to zero-valent molybdenum by TiO2.
Magnetic Interaction in Solvent-free DPPH and DPPH–Solvent Complexes
Authors: Fujito Teruaki 
Published: July 2006

Abstract
Magnetic interaction in solvent-free DPPH and DPPH–solvent complexes has been studied by means of measurements of the magnetic susceptibility, the proton magnetic resonance, and the low-field ESR at very low temperatures. The susceptibility of solvent-free DPPH shows a round maximum at 11 K, and then it decreases with a lowering of the temperature, no ordered state being observed. The DPPH–benzene (1 : 1) complex shows a round maximum of susceptibility at 0.65 K and antiferromagnetic ordering at about 0.40 K. The DPPH–CCl4 (4 : 1) complex shows a curious temperature dependence of the susceptibility, which is interpreted in terms of a two-magnetic sublattice model; one sublattice is in the singlet spin state, while the other is in the paramagnetic state at low temperatures except below 0.45 K. Pair interaction is dominant both solvent-free DPPH and in solvent complexes of DPPH. A theoretical approach to the ordered state of DPPH–benzene is given by taking the inter-pair interaction into account.
Liquid Crystal Formation in Binary Systems. IV. Induction of Smectic Phases in Mixtures of N-(p-Nitrobenzy lidene)-p-aminoazobenzene and Various Electron Donors of the Type N-(p-Substituted Benzylidene)-p-aminoazobenzene
Authors: Fukui Minoru , Matsunaga Yoshio 
Published: July 2006

Abstract
A study of the phase diagrams of binary systems consisting of nematogenic N-(p-nitrobenzylidene)-p-aminoazobenzene and various electron donors of the type N-(p-X-benzylidene)-p-aminoazobenzene revealed the induction of a smectic A phase in the cases where X=MeO, EtO, n-PrO, Me2N, and Et2N and of a smectic B phase as well in the cases where X=EtO and n-PrO. The extent of thermal stability enhancement of the smectic A phase is larger with non-nematogenic dialkylamino derivatives than with nematogenic alkoxy derivatives; this supports our postulate that the smectic phases are stabilized by the intermolecular interaction of the electron donor-acceptor type. The induction of smectic A phases was shown also in all the combinations of the p′-ethoxy derivatives, including the cases where X=H, Me, and Ph.
“Macromolecular Ion Flotation” of MnO4− by Combined Use of Macromolecular Anion and Cationic Surfactant
Authors: Sasaki Tsunetaka , Matsubara Kiyoo , Machida Ikuko 
Published: July 2006

Abstract
MnO4− ions in aqueous solution were subjected to macromolecular ion flotation, a process of flotation applied for an aqueous solution containing organic or inorganic ions to be floated, macromolecular ions including macroscopic or colloidal particles with an ion exchange capacity and polymer ions, and oppositely charged ionic surfactant. The macromolecular anions examined were basic aluminum chloride, polyaluminum chloride, carboxymethylcellulose, sodium polyacrylate, sodium alginate, potassium poly(vinyl sulfate), sodium hexametaphosphate, polyphosphoric acid, polyacrylic acid, bentonite, and sodium metasilicate. As a cationic surfactant, hexadecyltri-methylammonium chloride was used. All the above substances are effective for the MnO4− ion flotation, whereas low molecular substances such as Na3PO4 are ineffective, when used with the cationic surfactant. Molecular models of sublate formed during the macromolecular ion flotation are proposed.
Gas-Solid Chromatographic Studies of Organic Compounds on Zirconium Oxide Beads
Authors: Djordjevic Nebojša M , Milonjic Slobodan K , Kopecni Miroslav M 
Published: July 2006

Abstract
Adsorption properties of synthetic zirconium oxide beads were investigated by the gas-solid chromatography (GSC) method. Retentions of numerous alkanes, alkenes, aromatics and chlorinated compounds were measured in a wide temperature region. It appears that the surface activity of an adsorbent can be easily changed by thermal treatment, and in connection with it, the role of crystallographic structure of the adsorbent is emphasized. Thermodynamic parameters obtained were used for explanation of the adsorbent-adsorbate interaction.
The Design of Organic Metals. Dibenzotetrathiafulvalene-2,3-Dichloro-5,6-dicyano-p-benzoquinone (DBTTF–DDQ)
Authors: Mayerle James J , Torrance Jerry B 
Published: July 2006

Abstract
The electrical and optical properties of the four charge-transfer salts formed between the two donors tetrathiafulvalene (TTF) and dibenzotetrathiafulvalene (DBTTF) and the two acceptors tetracyanoquinodimethan (TCNQ) and 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ are compared. The differences are rationalized on the basis of electrochemical considerations. DBTTF–TCNQ, the compound composed of the weakest donor and acceptor, is found to be a neutral complex. However, TTF–TCNQ, and the new material DBTTF–DDQ are mixed valence and highly conducting. The latter material, which is the first highly conducting salt to contain the common acceptor DDQ, has a room temperature pellet electrical conductivity of 8 Ω−1 cm−1. Finally, the combination of best donor and acceptor, TTF–DDQ, forms an insulating, completely ionic salt. The structure of this salt has been determined and found to crystallize with relatively isolated dimers of TTF and strongly distorted stacks of DDQ.
Spectrophotometric Determination of Copper, Cobalt, Nickel, and Tellurium after Extraction with Morpholine-4-carbodithioate into Molten Naphthalene
Authors: Gautam Mamta , Bansal R K , Puri B K 
Published: July 2006

Abstract
Potassium morpholine-4-carbodithioate has been examined as a reagent for the spectrophotometric determination of copper, cobalt, nickel and tellurium after extraction into molten naphthalene. The extracted mixture of metal complex and naphthalene was dissolved in chloroform and the trace amounts of these metals determined spectrophotometrically. Beer’s law holds in the concentration range Cu: 5.0–70.0, Co: 5.0–81.0, Ni: 6.0–90.0, and Te: 5.7–125.0 μg per 10 ml of the final solution. The molar absorptivity and sensitivity are calculated to be Cu: 1.067×104 mol−1 cm−1, 0.0059 μg/cm2 (440 nm), Co: 1.350×104 mol−1 cm−1, 0.0043 μg/cm2 (360 nm), Ni: 7.920×103 mol−1 cm−1, 0.0088 μg/cm2 (390 nm), and Te: 1.075×104 mol−1 cm−1, 0.0110 μg/cm2 (415 nm). Aliquots containing 25.0 μg of copper, 27.0 μg of cobalt, 24.0 μg of nickel and 25.5 μg of tellurium gave a mean absorbance of 0.420, 0.620, 0.270, and 0.215 with a relative standard deviation of 0.0016, 0.0024, 0.0015, and 0.0013 respectively. The interference of various ions has been studied in detail. Only cobalt interfered in the determination of nickel which was eliminated by extraction first at low pH. Methods were developed for the determination of copper, cobalt and nickel in various alloys. A method was also developed for simultaneous determination of tellurium and selenium in the pure solution, based upon the thermal instability of seleniumelided carbodithioate complex.
The Effects of the BF2- and B(C2H5)2-substitiition for Bridging Hydrogen Atoms in the Cobalt(II), Nickel(II), and Copper(II) Complexes with Some Oximate Ligands
Authors: Nonaka Yasuomi , Hamada Kohsuke 
Published: July 2006

Abstract
Cobalt(II), nickel(II), and copper(II) complexes with dioximes substituted by BF2- and B(C2H5)2-groups for bridging hydrogen atoms were prepared. The BF2-substitution caused a red-shift of d-d band and increase of g⁄⁄-value for copper(II) complexes and positive shift of polarographic half wave potential of nickel(II) complexes. In the case of the B(C2H5)2-substituted complexes, such variations were not observed. The BF2-substituted cobalt(II) complexes are stable under an open atmosphere at room temperature in a solid state and in a DMF solution. These were interpreted in terms of the electron-withdrawing ability of BF2-group in the ligand.
Synthesis of Ethylene Glycol Acetates Catalyzed by Potassium Iodide and Metal Acetate
Authors: Shimizu Kazuo , Imamura Juichi 
Published: July 2006

Abstract
The catalytic activities of various kinds of binary systems consisting of KI and metal acetate were tested in liquid phase oxidation of ethylene in acetic acid at various pressures. KI–Mn(OCOCH3)2 was found to be the most reactive system and a new material, CH3COOCH2CH2OCOCH2OCOCH3, was formed as a major byproduct. It was also found that the main product at an early stage of the reaction was ethylene glycol monoacetate, from which other products were formed consecutively. It is considered that catalytic reaction does not proceed via ICH2CH2I, but via ICH2CH2OH which is formed by the oxidation of ethylene with HIO. On the basis of the rate equation and the results under various reaction conditions, a mechanism of the KI–Mn(OCOCH3)2-catalyzed reaction has been proposed.
Photochemical Nucleophilic Substitution Reactions of Methyl Substituted Derivatives of p- and o-Nitroanisole
Authors: Sawaura Masaki , Mukai Toshio 
Published: July 2006

Abstract
Photosubstitution reactions of several methyl substituted derivatives of p- and o-nitroanisole with hydroxide ion were investigated. The methyl substituent seemed to show an uncertain (probably electronic) effect in addition to the steric effect for the replacement of both the methoxy and the nitro groups. Mainly, the replacement reaction of the nitro group is discussed.
Persistent Nitrogen-centered Free Radicals, N-(Arylthio)-3,5-di-t-butylphenylaminyls. Decomposition Reactions
Authors: Miura Yozo , Yamamoto Akifumi , Kinoshita Masayoshi 
Published: July 2006

Abstract
N-(4-Chlorophenylthio) -3,5-di-t-butylphenylaminyl was decomposed in oxygen-free benzene, and the products were examined. On the basis of the results, the decomposition mechanism of the radical is described.
A Product from the Photo-induced Reaction of Cholesterol in the Presence of Lead Tetraacetate and Iodine
Authors: Suginome Hiroshi , Kato Kimitoshi 
Published: July 2006

Abstract
The irradiation of a benzene solution of cholesterol in the presence of lead tetraacetate and iodine gives cholest-5-en-3β-yl A-homo-4-oxacholest-5-en-3α-yl ether in a 23% yield.
Reaction of Thiobenzophenone S-Oxide (Diphenylsulfine) with Carbon Nucleophiles
Authors: Ohno Atsuyoshi , Uohama Misao , Oka Shinzaburo 
Published: July 2006

Abstract
The reaction of diphenylsulfine with a Grignard reagent or alkyllithium gives a variety of products depending on the structure of the Grignard reagent or alkyllithium.