bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bridges in Polynuclear Complexes. II. An X-Ray Investigation of the Coordination of Silver Ion to the μ-Peroxo Bridge of a Dinuclear Cobalt(III) Complex
Authors: Shibahara Takashi , Mori Masayasu , Matsumoto Keiji , Ooi Shun’ichiro 
Published: July 2006

Abstract
The crystal structure of [(en)2Co(NH2)(O2)Co(en)2](NO3)3·15/8(AgNO3)·H2O has been determined from X-ray diffraction data collected by the counter method. The crystal is monoclinic with the space group C2/c and with a=8.710(3), b=16.413(5), c=20.024(8)Å, β=90.30(4)°, and Z=4. The structure was refined by the block-diagonal least-squares method to R=0.107 for 2157 independent reflections. It has been elucidated that the Ag atom is bound to each of the two peroxo oxygen atoms with the Ag–O bond length of 2.27(1) Å. Each Ag atom is also surrounded by two more oxygen atoms belonging to the nitrate anions and these Ag–O bond lengths are 2.45(2) and 2.50(2) Å. The central five-membered ring has a symmetric envelope conformation, with the peroxo O atom deviating from the Co, N, Co plane, by 0.38 Å. The crystals contain an equal amounts of the enantiomeric forms (δδΛδδδ) and (λλΔλΔλλ). The formation constant of Ag+ and [(en)2Co(NH2)(O2)Co(en)2]3+ in aqueous solution was found to be less than 0.5.
Isobaric Thermogravimetry of the Gas Encapsulation with Molecular Sieves A
Authors: Takaishi Tetsuo , Kamei Yujiro , Yusa Atsushi , Ohgushi Tatsuo 
Published: July 2006

Abstract
The isobaric gas sorption with (Na,Ca)–A and (K,Ca)–A zeolites was measured gravimetrically in temperature ranges of −160–−40 °C for O2 and N2, and of room temperature—200 °C for n-C4H10. The sorption hysteresis, i.e., the gas encapsulation was observed. The maximum point, in the temperature rising branch of the isobar, was located at about −90 °C for N2 and in the range 120–170 °C for n-C4H10, and shifted to the lower temperature side with the increasing content of calcium for n-C4H10. The observed results are explained in terms of an incomplete blocking action of cations on window sites. This incompleteness was amplified by bivalent cations introduced onto other sites than the window sites, and the sieving character of the ion-exchanged zeolite was delicately modified.
The Reduction of Sulfuric Acid by Hydrogen on Various Metal–Carbon Catalysts
Authors: Katagiri Akira , Watanabe Kiyoshi , Yoshizawa Shiro 
Published: July 2006

Abstract
The reduction of sulfuric acid, which is formed on the activated carbon catalyst in the course of removing sulfur dioxide from exhaust gas, was investigated. The platinum, palladium, silver, and copper on activated carbon were found to be catalytically active in the reduction of sulfuric acid by hydrogen, while manganese, iron, cobalt, nickel, and zinc were found to be inactive. The copper–carbon catalyst is favorable, because sulfuric acid was reduced selectively to sulfur dioxide on it at temperatures from 190 °C to 270 °C. On the platinum–carbon catalyst, the reduction occurred at a relatively low temperature (140 °C to 200 °C), but hydrogen sulfide and elemental sulfur were formed in addition to sulfur dioxide. It is concluded from thermodynamic calculations that catalytically active metals were in the metallic state on activated carbon under the present reaction conditions. An electrochemical mechanism is proposed for the reaction.
Jasmonoid Synthesis from sci-4-Heptenoic Acid
Authors: Sato Toshio , Kawara Tatsuo , Sakata Kazumi , Fujisawa Tamotsu 
Published: July 2006

Abstract
Jasmonoids with cis-2-pentenyl side chain such as cis-jasmone, methyl jasmonate, and jasmolone were easily synthesized from cis-4-heptenoic acid obtained by the ring opening reaction of β-propiolactone with di-cis-butenylcuprate.
Synergistic Solvent Extraction of Alkali Metal Picrates by Crown Ethers
Authors: Takeda Yasuyuki 
Published: July 2006

Abstract
The solvent extraction of rubidium and caesium picrates has been studied between benzene and water at 25 °C in the presence of tributyl phosphate (B), 12-crown-4 (12C4), 15-crown-5 (15C5), or both B and 15C5, and the complex-formation constants for the synergistic reactions in the benzene solution have been calculated. For both rubidium and caesium, the sequences of the complex-formation constants for these ligands are B&lt;12C4&lt;15C5, indicating that the complex-formation constant increases with an increase in the number of the donor oxygen atoms of the ligand. The complex-formation constant of rubidium is greater than that of caesium in every system.
The Solubility Curves of Water in Normal Alkane Derivatives with a Polar Group
Authors: Nishino Nobuo , Nakamura Masao 
Published: July 2006

Abstract
Measurements were made of the solubility vs. temperature curves of water in normal alkane derivatives: alkanols, alkylamines, and alkanoic acids. The solubility of water increases monotonically with an increase in the temperature in alkanols and alkanoic acids, while it decreases in alkylamines. The solubility is so great that it often exceeds 1/2 in the mole fraction scale. Phase diagrams were constructed by combining such solubility curves with the solubility curves of these substances in water. The heat of solution at an infinite dilution vs. the temperature for 1-butanol in water is obtained by taking account of the activity coefficient of 1-butanol in its own phase.
Steady-state and Picosecond Studies of Energy Transfer between Dyes with Closely Located S1-Levels. Rhodamine-6G and 3,3′-Diethyl-thiacarbocyanine Iodide in Acetone Solution
Authors: Kusumoto Yoshihumi , Sato Hiroyasu , Maeno Kazuto , Yahiro Shuichi , Nakashima Nobuaki 
Published: July 2006

Abstract
Lasing wavelengths and fluorescence spectra were measured for a mixed dye system containing various concentrations of Rhodamine 6G (Rh-6G) and 3,3′-dietriylthiacarbocyanine iodide (DTC), which have very closely located S1 levels, in acetone at room temperature. A new way of confirming the occurrence of energy transfer is presented on the basis of the reabsorption effect. It was found that most of the pump power absorbed by Rh-6G is transferred to DTC. A study of the fluorescence decay by a picosecond laser revealed that the energy transfer is essentially governed by the Förster mechanism. The observed fluorescence decay data agree fairly well with the R0 value of 73.2 Å calculated from the spectral overlap.
Liquid-Liquid Extraction and Separation of Lanthanum (III)
Authors: Langade A D , Shinde V M 
Published: July 2006

Abstract
Separation of lanthanum(III) from iron(III), molybdenum(VI), vanadium(V), chromium(VI), titanium(IV), bismuth(III), zirconium(IV), scandium(III), uranium(VI), and beryllium is achieved by solvent extraction with mesityl oxide from sodium salicylate solution (0.1 M adjusted to pH 7). Lanthanum from the organic phase is stripped with water and determined photometrically as its arsenazo complex at 570 nm. The extracted species is trisolvated i.e. La(HOC6H4COO)3·3MeO. The results of separation are reported.
The Selective Preparation of N-Acylindigo
Authors: Omote Yoshimori , Fujiki Kiyoko , Awano Hiroshi , Kubota Ikuo , Nishio Takehiko , Aoyama Hiromu 
Published: July 2006

Abstract
The hitherto unknown N-acylindigo has been selectively prepared by heating the corresponding known N,N′-diacylindigo in aqueous pyridine. The data of N-acetyl, N-benzoyl, N-(p-toluoyl), N-(p-chlorobenzoyl), N-(p-nitrobenzoyl), and N-(3,5-dinitrobenzoyl)indigo are summarized.
Reaction of Allyl Diphenyl Phosphates with Soft Bases
Authors: Araki Shuki , Minami Kazuhiro , Butsugan Yasuo 
Published: July 2006

Abstract
The title phosphates were found to react with a variety of soft bases to give nucleophilic substitution products in high yields. The reaction proceeded regiospecifically under mild reaction conditions with preservation of the double bond geometry.
A Method for Independent Determination of Equilibrium Constant and Molar Absorptivity of Molecular Complexes from Spectrophotometric Data
Authors: Seal Bejoy Kumar , Sil Harideb , Banerjee Manas , Mukherjee Dulal Chandra 
Published: July 2006

Abstract
Two separate equations, one cubic in K and the other quadratic in ε, have been developed for calculating K and ε of molecular complexes independently of each other. The equations on testing with various spectrophotometric data yielded values of K and ε which agree with those obtained by others using well known procedures.
Negative Ions Formed by Vacuum Spark Discharge. II. Relative Sensitivity Coefficients for Negative Ions of the Elements Contained in Compressed Aluminium Powder Electrodes for Spark Source Mass Spectroscopy
Authors: Kishi Hiroshi 
Published: July 2006

Abstract
The relative sensitivity coefficients for negative ions of 15 elements contained in compressed aluminium powder electrodes were measured by spark source mass spectroscopy. The relative sensitivity coefficients for the halogens and group VIB elements were found to be the largest, the difference of relative sensitivity coefficients between the elements being larger than in the case of positive ion relative sensitivity coefficients. The logarithm of the relative sensitivity coefficients of negative ions are linearly correlated to the electron affinities of the elements.
The Polarized Spectra and Thermal Diffusivity of Brown Tourmaline as Studied by Photoacoustic Spectroscopy
Authors: Sugitani Yoshinori , Fujinami Masahisa 
Published: July 2006

Abstract
The strong pleochroic band of brown tourmaline at around 24000 cm−1 in the E⊥ c photoacoustic spectra was assigned to d-d(6A1→4A1, 4E) transition of Fe and to charge transfer of Ti, that in the E//c spectra being entirely assigned to charge transfer of Ti. The analysis of the photoacoustic signal intensity vs. chopping frequency gave the thermal diffusivity constant of tourmaline as α=0.15 cm2/s.
The Mechanism of the Hydrolysis of Polyphosphates. V. The Effect of Cations on the Hydrolysis of Pyro- and Triphosphates
Authors: Watanabe Makoto , Matsuura Makoto , Yamada Tamotsu 
Published: July 2006

Abstract
The effect of cations on the rate of hydrolysis of pyro- and triphosphates was studied by adding metal chloride to aqueous solutions of the phosphates. The concentrations of the phosphates and metal chlorides were 0.025 and 0.1 mol dm−3 respectively. Alkali metal, alkaline earth metal, aluminium, and some transition-metal (Mn(II), Co(II), Ni(II), Cu(II), and Zn(II)) cations retarded the hydrolysis of the phosphates in acidic media. The following sequence of efficiency resulted:
trivalent&gt;bivalent&gt;univalent.
The efficiency of elements within one group of the periodic table decreased from top to bottom. On the other hand, in alkaline solutions, alkali metal cations accelerated the hydrolysis of the phosphates and the catalytic effectiveness decreased with an increase in the ionic radius.
Mechanism of the Reaction of Nitriles with Alkaline Hydrogen Peroxide. Reactivity of Peroxycarboximidic Acid and Application to Superoxide Ion Reaction
Authors: Sawaki Yasuhiko , Ogata Yoshiro 
Published: July 2006

Abstract
Formation of peroxycarboximidic acid (1) is not rate-determining in the reaction of nitrile with alkaline hydrogen peroxide to form amide and oxygen; the yield of amide based on H2O2 varies from 20 to 60%. When dimethyl sulfoxide (DMSO), a reactive substrate, is added, the rate is independent of [DMSO] and governed in turn by a rate-determining addition of HOO− to nitrile. This reaction gives a reliable α-value of kHOO−/kHO−, which is 10000 for benzonitrile. A facile conversion of nitrile to amide may be achieved by the reaction in the presence of DMSO, unaccompanied by side reactions such as the epoxyamide formation from α,β-unsaturated nitrile. Kinetics and product analysis suggest that a predominant reaction is not a non-radical oxidation of H2O2 with 1 but a radical decomposition of H2O2 which is induced by the homolysis of anion of 1 (1A). No singlet oxygen could be trapped chemically. The reaction of superoxide ion, O2\ewdot, with acetonitrile is shown to be analogous to that of HOO−; the decomposition of O2\ewdot is fast in the presence of MeCN and DMSO in benzene, affording acetamide and dimethyl sulfone.
New Synthetic Route for the Preparation of 4-Phenylthio-4-butanolide Derivatives by the Use of the Pummerer Rearrangement
Authors: Watanabe Mikio , Nakamori Seijin , Hasegawa Hatsue , Shirai Kozo , Kumamoto Takanobu 
Published: July 2006

Abstract
The Pummerer rearrangement reaction of 2- or 3-substituted 4-(phenylsulfinyl) butyric acids in the presence of an excess amount of acetic anhydride and a catalytic amount of p-toluenesulfonic acid in refluxing toluene for 1 h afforded 2- or 3-substituted 4-phenylthio-4-butanolide (17a–f). Thermolysis in pyridine of 4-phenylsulfinyl 4-butanolides, which were prepared by oxidation of 17a–f, afforded 2- or 3-substituted 2- or 3-buten-4-olides.
Acylchlorination and Related Reactions of Fluoroethenes Using AlCl3 and FeCl3
Authors: Ishikawa Nobuo , Iwakiri Hiroshi , Edamura Kazuya , Kubota Satoshi 
Published: July 2006

Abstract
Acylchlorination of mono-, 1,1-di-, and trifluoroethenes with carboxylic acid chlorides using AlCl3 and FeCl3 as a Lewis acid was investigated. In AlCl3-catalyzed reactions, fluorine-chlorine exchange reaction always occurred in part, while in FeCl3-catalyzed reactions Claisen-type condensation giving β-diketones was observed. Preparations of 2-chloro-2-fluoroethyl, 2-chloro-2,2-difluoroethyl, and 2-chloro-1,2,2-trifluoroethyl ketones are given.
Crystal Structures of Mixed Ligand Copper(II) Complexes Containing l-Amino Acids. II. (l-Alaninato)aqua(l-histidinato)copper(II) Trihydrate
Authors: Ono Taizo , Sasada Yoshio 
Published: July 2006

Abstract
Copper(II) complex containing l-alanine and l-histidine crystallizes from aqueous solution at pH 7.0. Crystals of (l-alaninato)aqua(l-histidinato)copper(II) trihydrate are monoclinic, space group P21 a=10.980(4), b=7.362(3), c=9.700(2) Å, β=101.45(3)°, and Z=2. There is some disorder for the location of three water molecules of crystallization. Four coordinating atoms in an approximately planar arrangement around copper are the α-amino nitrogen and imidazole δ-nitrogen of l-histidine, and α-amino nitrogen and α-carboxyl oxygen of l-alanine. They take a cis conformation with respect to the amino groups. The axial site is occupied with oxygen atom of water, so that the coordination geometry is square-pyramidal. Similarity and difference are discussed in comparison with the coordination mode in copper complexes containing l-histidine and l-asparagine.
Near-infrared Magnetic Circular Dichroism Studies on Iron(III) Horse Heart Cytochrome c
Authors: Kobayashi Nagao , Nozawa Tsunenori , Hatano Masahiro 
Published: July 2006

Abstract
Magnetic circular dichroism (MCD) spectra in the near-infrared region reported first for oxidized cytochrome c in its neutral (pH 5.58), alkaline (pH 11.62), and acidic (pH 1.88) forms exhibit temperature dependence, indicating that they are composed of Faraday C terms, except for the acidic form. The relation between the near-infrared MCD and the heme vicinity is discussed in terms of the structures for the heme chromophore of cytochromec.
The 1H NMR Spectra of [(CH3)2 SbCl2(oxine)] in Several Solvents
Authors: Kawasaki Yoshikane , Kinoshita Masahiro 
Published: July 2006

Abstract
The 1H NMR spectra of dichlorodimethyl(8-quinolinolato)antimony(V), [(CH3)2SbCl2(oxine)], were measured in several solvents. Two methyl signals were observed in some aromatic and aliphatic solvents, although only one signal was detected in dichloromethane. The results were explained by the presence of two isomers in solution.
Photoelectrochemical Behavior of Chlorophyll a-Lipid Films on a Platinum Electrode in an Aqueous Electrolyte
Authors: Miyasaka Tsutomu , Fujishima Akira , Honda Kenichi 
Published: July 2006

Abstract
The photoelectrochemical behavior of chlorophyll a-lipid mixed monolayers coated on a platinum electrode by the Langmuir-Blodgett technique was investigated under potentiostatic conditions in an aqueous electrolyte in the absence of redox agents. Under illumination, cathodic photocurrents were observed at electrodes coated with a sufficient number of monolayers. The quantum efficiency of the photocurrent was estimated to be about 10−4, much lower than that obtainable for dye-sensitized photocurrent on semiconductor electrode. The cathodic photocurrent increased with lowering in the pH of electrolyte. The possibility of the photoreduction of water by excited triplet chlorophyll a is discussed on the basis of observed pH dependence and correlation of the redox potentials involved.
The Effect of Propyl Cellosolve on Water Structure Estimated from Ultrasonic Data
Authors: Nishikawa Sadakatsu , Yamashita Yoshihisa , Mashima Mitsuo 
Published: July 2006

Abstract
Ultrasonic absorption and velocity have been measured in aqueous solution of Propyl Cellosolve (ethylene glycol monopropyl ether) in the frequency range of 7.5 to 220 MHz at 25 °C. A single relaxational process has been found and the mechanism has been attributed to the solute-solvent interaction, AB↔A+B. The rate constants obtained are k12=9.6×107 s−1 for the forward and k21=1.3×108 M−1 s−1 for the backward reaction. The effect of the solute on the water structure has been found to act slightly as the water structure promoter and the results have been discussed comparing with those of Butyl Cellosolve solution.
Separation of Selenide Constituents from Selenide Samples Containing Elemental Selenium
Authors: Tamari Yuzo , Hiraki Keizo , Nishikawa Yasuharu 
Published: July 2006

Abstract
The valence state analysis to determine selenide in mixtures of selenide, elemental selenium, selenite, and selenate compounds was devised by the selective volatilization of selenium as its hydride. As the optimum conditions of the reaction, 6 M (this unit is defined to 1 M=1 mol dm−3 as below.) hydrochloric acid solution was dropped into the mixture and the hydrogen selenide gas generated was absorbed in a solution of sodium hydroxide and hydrogen peroxide. The optimal reaction temperature was found to be 170 °C for 40 min using nitrogen as the carrier gas. Utilizing this method, the fluctuation of the oxidation state of selenium was observed during the storage of zinc selenide samples.
Thermal Reactions of Octahedral Nickel(II) Complexes Containing N,N- and N,N′-Dialkylethylenediamines in a Solid Phase
Authors: Ihara Yoshinori , Izumi Eiichi , Uehara Akira , Tsuchiya Ryokichi , Nakagawa Shigeo , Kyuno Eishin 
Published: July 2006

Abstract
Thermal reactions of the [Ni(H2O)2(AA)2]X2·nH2O complexes in a solid phase were investigated, where AA is N,N′-diethylethylenediamine (NN′-deen), N,N-dimethylethylenediamine (NN-dmen), or N,N′-dimethylethylenediamine (NN′-dmen), and where X− is Cl−, Br−, I−, NO3− or ClO4−. By means of thermal analyses and spectral and magnetic measurements in a series of these complexes before and after heating, the following results were obtained. In the case of the NN′-deen complexes, only the perchlorate deaquates to change from octahedral to square-planar, but the other salts, such as the chloride, bromide, iodide, and nitrate, undergo deaquation-anation keeping their octahedral configuration. The deaquation-anation was also observed in the chloride, bromide, and nitrate of the NN-dmen complexes, but the iodide deaquated, and so was transformed from octahedral to square-planar. In the NN′-dmen complexes, only deaquation-anation was detected, irrespective of the anions (Cl−, Br−, I−, and NO3−). The effects of N-substituents in the diamines and the anions on the above transformation were discussed.
Studies on Characteristics of Electron Capture Responses. VI. A Consideration on the Response Mechanism of the Electron Capture Detector
Authors: Takeuchi Masahiro 
Published: July 2006

Abstract
In order to improve the understanding of the electron capture detector (ECD), a study on the response mechanism has been carried out by using the pulse sampling technique. The ECD currents in the presence and the absence of electron capturing molecules were measured under various pulse conditions. The responses of the ECD probably arise from the current drop based on the slower electron drift velocity in the presence of electron capturing molecules than that in the absence of them.
The Transition Metal-catalyzed N-Alkylation and N-Heterocyclization. A Reductive Transformation of Nitroarenes into (Dialkylamino)arenes and 2,3-Dialkyl-substituted Quinolines Using Aliphatic Aldehydes under Carbon Monoxide
Authors: Watanabe Yoshihisa , Suzuki Naoki , Tsuji Yasushi , Shim Sang Chul , Mitsudo Take-aki 
Published: July 2006

Abstract
The catalytic N-alkylation and N-heterocyclization of nitroarenes occur at 180 °C under a carbon monoxide pressure of 70 atm and in the presence of aldehyde and such transitionmetal complexes as rhodium and palladium complexes, thus giving 2,3-dialkyl-substituted quinolines and (dialkylamino)arenes in good yields. The product selectivity depends greatly on the catalysts: a binary catalyst, RhCl(PPh3)3 and PdCl2, is effective for the N-heterocyclization, while [Rh2Cl2(cod)2] is effective for the N-alkylation.
The Replacement of Electronegative Substituents by an Electron-transfer Mechanism. The Factors Governing the Reaction of Carbonyl and Imino Compounds with Organomagnesium Reagents
Authors: Okubo Masao , Uematsu Yumiko 
Published: July 2006

Abstract
For the purpose of studying the electron-transfer initiated replacement of ortho-methoxy and ortho-halogeno substituents of diaryl ketone anils by the aryl group of ArMgBr, eight anils were prepared. The expected o-methoxy replacement by the phenyl group of PhMgBr, however, was extremely slow, and no o-chloro replacement took place. In contrast, anils of 1-substituted (MeO, Br, Cl) fluorenones gave the replacement products: The distribution of by-products formed via radical pathway in the cases of halogeno-anils was clearly different from that in the case of the methoxy-anil. In the reaction with ArN(MgBr)2, 1-halogenofluorenones afforded the normal condensation products, while 1-methoxyfluorenone gave the “condensation-replacement” product. On the basis of the characteristic product-distributions obtained in the two organomagnesium reactions, the mechanism of methoxy replacement was distinguished from that of halogen replacement. Factors governing the two reactions were proposed and discussed: The structures of the substrates favorable to spin-delocalization, the electron-accepting ability of the substrates, the electron-donating ability of the reagents, the leaving ability of substituents, and their leaving manner.
Photochemical Electrocyclic Reaction Mechanism of Methyleneamine N-Oxide to Form Oxaziridine. MINDO/3 CI Study
Authors: Kikuchi Osamu , Morihashi Kenji , Suzuki Keizo 
Published: July 2006

Abstract
The photochemical electrocyclic reaction mechanism of methyleneamine N-oxide to form oxaziridine was explored on the basis of the potential energy surfaces obtained by the MINDO/3 CI calculation. The strong interaction between the ground state and the doubly-excited state, which appears in the disrotatory cyclization process of the corresponding hydrocarbon system, was not observed. Instead, a deep potential well, which can be a leakage channel from the excited state to the ground state, was found in the S1 surface. The predicted reaction path is characteristic of hetero-atom conjugated systems, and an important participation of the oxygen σ lone-pair electrons is expected in this reaction path.