bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Thermal Decomposition of Potassium Trioxalatoferrate(III) Trihydrate
Authors: Tanaka Nobuyuki , Sato Katsuya 
Published: July 2006

Abstract
The thermal decomposition of K3[Fe(C2O4)3]·3H2O in solid state was studied by the thermogravimetric, the infrared spectroscopic and the manometric methods. It was found that, with elevating temperatures, three moles of water were evolved as the first step to form an anhydrous complex K3[Fe(C2O4)3], which was then decomposed as the second step by an electron transfer from a ligand to the central iron(III) with the formation of an iron(II) complex. K2[Fe(C2O4)2], K2C2O4 and CO2 were found as products in the second step. The total pressure of CO2 gas evolved was measured at suitable time intervals. The shape of a curve of α (the fraction isothermally decomposed) vs. t (time) was sigmoidal. The initial part of the decomposition reaction was kinetically of a first-order and the activation energy was obtained to be 43.6 kcal/mol. A main part of it (0.2&lt;α&lt;0.8) was of a second-order and obeyed the Prout-Tompkins’ law. The activation energy was calculated to be 35.3 kcal/mol.
Synergistic Effect in Solvent Extraction—Effect of Oxygen and Nitrogen Containing Organic Bases on the Stability of Zinc(II) and Cobalt(II) β-Diketonate Adducts—
Authors: Shigematsu Tsunenobu , Honjyo Takaharu , Tabushi Masayuki , Matsui Masakazu 
Published: July 2006

Abstract
The effect of the organic Lewis bases acting as a synergist on the extraction of zinc(II) and cobalt(II) with benzoyltrifluoroacetone was studied. n-Hexyl alcohol, TBP TBPO and TOPO were used as oxygen-containing bases, and quinoline, isoquinoline, lepidine, acridine and quinaldine as nitrogen-containing bases. The stability constants between metal chelates and the adduct forming materials in the organic phase were obtained by curve fitting method. The results are summarized as follows: (1) Zinc(II) and cobalt(II) chelates formed adducts including one or two molecules of the bases per metal ion. Adduct formation was carried out successively. (2) The stability of adducts with oxygen-containing organic bases increased in the order, n-hexyl alcohol&lt;TBP&lt;TBPO≈TOPO. This is the same order with that of the basicity of donor oxygen in the compounds. The stability of adducts with nitrogen-containing bases increased in the order, quinaldine&lt;acridine&lt;quinoline&lt;lepidine&lt;isoquinoline. In this case, however, the steric effect of the bases preferably contributed to the adduct formation. (3) The overall stability constants of the adducts are affected by the coordination number of the metal ions. Cobalt(II) adducts are more stable than zinc(II) adducts.
Studies on the Substrate Specificity of Taka-amylase A. III. Syntheses of Some New Derivatives of Phenyl α-Maltoside
Authors: Arita Hitoshi , Isemura Mamoru , Ikenaka Tokuji , Matsushima Yoshio 
Published: July 2006

Abstract
In order to obtain information of the interaction between various portions of the substrate molecule and the enzyme protein, mono-O-methyl derivatives of phenyl α-maltoside and its analogues were synthesized and the enzymatic action was investigated. The purity and chemical structure of the compounds were confirmed by chromatographic method, phenol determination, and elemen talanalyses. The anomeric configuration of the glycosidic linkage to phenol was presumed to be of an alpha type on the basis of the high positive value of specific rotation. Some regularities in the enzymatic action on these synthetic substrates were observed.
Thermal Decomposition of Uranyl Dihydrogen Orthophosphate Trihydrate
Authors: Kamo Mutsukazu , Ohashi Shigeru 
Published: July 2006

Abstract
The thermal decomposition of uranyl dihydrogen orthophosphate trihydrate was studied by means of paper chromatography, X-ray diffractometry, differential thermal analysis, thermogravi-metric analysis, infrared spectroscopy and chemical analysis. From these studies, it was revealed that in the thermal decomposition of the uranyl salt the following reactions take place. 1) The formation of condensed phosphates with relatively small polymerization degrees such as di- and triphosphates takes place below 300°C, accompanied by the elimination of water. 2) A uranyl salt of long-chain metaphosphate, [UO2(PO3)2]n is produced bewteen 300 and 840°C. 3) The metaphosphate is melted at about 900°C, while uranium(VI) is reduced to uranium(IV) at the same time. 4) As a result of the reduction, the formation of uranium(IV) diphosphate, UP2O7, starts. 5) Finally, almost pure uranium(IV) diphosphate is produced at 1200°C.
The Formation of Pyrazolo[1,5-a]pyrimidine Derivatives
Authors: Hori Isaburo , Saito Koji , Midorikawa Hiroshi 
Published: July 2006

Abstract
The combination reactions of 3-alkyl-2-cyano-3-methoxyacrylic esters (I) and their 3-hydrazino derivatives (II) in the presence of pyridine in alcohol at room temperature mostly gave chain intermediates, whose cyclizations led to the formation of only 2,7-dialkyl-5-hydroxypyrazolo-[1,5-a]pyrimidine derivatives. On the other hand, the reaction of Ia (3-Me) with the 5-aminopyrazole derivative (IIIa) obtained by the cyclization of IIa (3-Me) gave 7-hydroxy- and 7-aminopyrazolopyrimidine derivatives in alcohol under reflux via an intermediate. The reactions of 2-cyano-3-ethoxycrotononitrile with IIa or IIIa both afforded 7-aminopyrazolopyrimidine derivatives directly.
Reactions of Nitrones with Free Radicals. I. Radical 1,3-Addition to Nitrones
Authors: Iwamura Michiko , Inamoto Naoki 
Published: July 2006

Abstract
Reactions of the aldonitrones with α,α′-azobisisobutyronitrile or dimethyl α,α′-azobisisobutyrate gave trisubstituted hydroxylamines as addition products, whose structures were determined to be radical 1,3-addition products to the nitrones. Reactions of N-benzyl-α-phenylnitrone with di-t-butyl peroxide and aralkyl hydrocarbons possessing at least one α-hydrogen atom gave similar 1,3-adducts and substituted N-benzylaldonitrones. Reaction of α,N-diphenylnitrone with phenylazotriphenylmethane gave similarly α,α,N-triphenylnitrone. Mechanisms for the formation of these products were discussed.
The Structure of Salts of β-Dione Dioximes
Authors: Iwakura Yoshio , Uno Keikichi , Haga Kazuo 
Published: July 2006

Abstract
Cyclohexane-1,3-dione dioxime hydrochloride was prepared and investigated with reference to its structure. Analysis and a study of its NMR and IR spectra suggested that the salt is the enamine form of the oxime. Further, the salts of 5-methylcyclohexane-1,3-dione dioxime, 5,5-dimethylcyclohexane-1,3-dione dioxime and acetylacetone dioxime were prepared and found to have the same structure.
Effect of Pressure on Graphitization of Carbon. VII. Effect of Pre-Heat-Treatment on Graphitization of Carbon under High Pressure
Authors: Kamiya Kan-ichi , Inagaki Michio , Saito Hajime , Noda Tokiti 
Published: July 2006

Abstract
The soft carbon samples PV-15, -17 and -20, and the hard carbon samples PH-15 and -20, which were prepared by pre-heat-treatment of a polyvinylchloride coke PV-7 at 1500, 1700 and 2000°C and a phenolformaldehyde resine char PH-7, at 1500 and 2000°C, respectively, under reduced pressure, were re-heat-treated under quasi-hydrostatic pressure of 5 kbar. The strctural changes in these carbons by the re-heat-treatment under pressure were studied by X-ray diffraction analysis. On the soft carbons, the rate of development of graphitic compenent was found to become small with the increase in temperature pre-heat-treatment. On these samples, especially on PV-20, the normal homogeneous graphitization of turbostratic component was observed above about 1700°C besides the heterogeneous graphitization. However, the hard carbon samples PH-15 and PH-20 showed the same abrupt heterogeneous graphitization at around 1500°C as the original PH-7. These results suggest that the structure of carbon sample is related to the heterogeneous graphitization under high pressure. One can deduce a conclusion from results of this series of experiments that the heterogeneous graphitization is more dominant in a carbon sample having a lower degree of graphitization, for example, a larger c0-spacing and a smaller crystallite size.
Cobalt(II, III), Nickel(II) and Copper(II) Complexes with Tetra-and Hexamethylenediaminetetraacetate
Authors: Ogino Hiroshi , Kobayashi Shigeru , Tanaka Nobuyuki 
Published: July 2006

Abstract
Synthesis of new complexes of cobalt(II), cobalt(III), nickel(II) and copper(II), [Co2hdta]·6.5H2O, K[Co tdta]·3H2O, [Ni2 hdta]·6.5H2O, Na2[Cu tdta]·6H2O, [Cu2 tdta]·1.5H2O and [Cu2 hdta]·6.5H2O, has been carried out, where tdta and hdta represent (OOCCH2)2N(CH2)4N(CH2-COO)24− and (OOCCH2)2N(CH2)6N(CH2COO)24−, respectively. The infrared, nuclear magnetic resonance and visible and ultraviolet absorption spectra were measured. The infrared and the NMR spectra of the Co(III) complex with tdta indicate that a quadrivalent tdta anion behaves as a hexadentate in this complex.
Non-Equilibrium Thermodynamics: Steady State Thermodynamic Relations in the Non-Linear Current-Affinity Region
Authors: Tykodi R J 
Published: July 2006

Abstract
A simple heat conduction example is used to show that the choice of boundary conditions for describing a steady process, although of no consequence in the linear current-affinity region, governs the applicability (or the lack thereof) of various thermodynamic assertions to the non-linear current-affinity region. The need for a whole family of classificatory principles to aid us in organizing our knowledge about steady processes is pointed out.
Alkoxysilanes. VII. The Preparation of Alkylalkoxysiloxanes
Authors: Kijima Ichiro , Okuda Keisuke , Abe Yoshimoto 
Published: July 2006

Abstract
Trimethylsiloxytri-t-butoxysilane (I), bis(trimethylsiloxy)di-t-butoxysilane (II), and bis(trimethylsiloxy)bis(tri-t-butoxysiloxy)silane (III) were prepared by the reaction of trimethylchlorosilane with tri-t-butoxysilanol, di-t-butoxysilanediol, and bis(tri-t-butoxysiloxy)silanediol respectively. Bis(tri-t-butoxysiloxy)dimethylsilane (IV) was also obtained by the reaction of dimethyldichlorosilane with tri-t-butoxysilanol. The reaction of dimethyldichlorosilane with di-t-butoxysilanediol or bis(tri-t-butoxysiloxy)silanediol gave tetramethyltetra-t-butoxy (V) or tetramethyltetra(tri-t-butoxysiloxy)cyclooctasiloxane (VI). These compounds were identified by means of elemental analysis, molecular-weight determination, and a study of the IR and NMR spectra.
Stereoselectivity of Phenylcarbenoid of Zinc in Cycloaddition with Olefin
Authors: Nishimura Jun , Furukawa Junji , Kawabata Nariyoshi , Koyama Hiroaki 
Published: July 2006

Abstract
The stereoselectivity of phenylcarbenoid of zinc generated from diethylzinc and benzal iodide was investigated in the cycloaddition reaction with olefin. The carbenoid showed larger syn-selectivity than phenylcarbenoid of lithium. Electron-donating substituent attached to the phenyl group of the phenylcarbenoid enhanced the syn-selectivity of the carbenoid. The syn-selectivity of the phenylcarbenoid was larger in ether than in n-pentane, contrary to the case of phenylcarbenoid of lithium.
Electronic Structures of the Oxocarbon Anions. III. Application of the Extended Hückel and Variable Electronegativity Extended Hückel Methods
Authors: Sakamoto Kazuyoshi , I’Haya Yasumasa J 
Published: July 2006

Abstract
The extended Hückel (EH) method with different basis functions and the variable electronegativity extended Hückel (VEEH) method are applied first to the calculation of the electronic structure of CO and then to that of three oxocarbon anions, (C4O4)2−, (C5O5)2−, and (C6O6)2−. MO energies of CO calculated by both methods are closer to those computed by a non-empirical SCF method and also to observed values, compared with those obtained by the CNDO/1 method. It is also found for CO and the three anions that in the EH method the charge distributions are not dependent on the basis functions chosen and are much more localized on the oxygen atoms than in the VEEH method. The latter method yields a π-electron distribution which is close to that predicted by the variable electronegativity π-electron SCF method. The EH and VEEH methods predict reasonable values for the lower excitation energies of these oxocarbon anions; specifically the calculated σ→π* excitation energy of (C4O4)2− agrees well with an observed value.
The Emission Spectra of Pyrazine and Deuterated Pyrazines in the Vapor and in Rigid Matrices at 90°K
Authors: Ishii Hajime , Koyanagi Motohiko , Kanda Yoshiya 
Published: July 2006

Abstract
Emission spectra of pyrazine and its deuterated derivatives have been observed in the vapor and the vibronic structure has been analyzed in detail. The vibronic structures of the phosphorescence spectra of these compounds have been explained all in terms of totally symmetrical vibrations, while the first main bands of the fluorescence spectra were anomalous as well as their progression bands in respect to the band position and intensity distribution. For comparison, the fluorescence spectra have also been studied in rigid matrices at 90°K.
Spectroscopic Determination of Quenching Cross-Sections of Excited Mercury Atoms (63P1, 63P0) in Molecular Collisions
Authors: Horiguchi Hiroyuki , Tsuchiya Soji 
Published: July 2006

Abstract
The concentrations of Hg(63P1) and (63P0) atoms, [Hg1*] and [Hg0*], were determined from the absorptions of 4358 and 4047 Å lines in the Ar-diluted mercury vapor in the presence of several quenching molecules, under the radiation of 2537 Å emission. An apparent absorption intensity was not proportional to [Hg1*] or [Hg0*], and was sensitive to the ratio of the spectral half-width of the light source to that of the absorption line. Therefore, a method to correct an absorption intensity was proposed. The relation of [Hg1*] to [Q], a concentration of quenching molecules, is explained well by the Stern-Volmer equation. The value of [Hg0*] increases with [Q] until it reaches a maximum at a certain value of [Q], and a further increase of [Q] results in a decrease of [Hg0*]. These findings are explained well by the following mechanism: (1) Hg+hν→Hg1*, (2) Hg1*→Hg+hν, (3) Hg1*+Q→Hg+Q, (4) Hg1*+Q→Hg0*+Q, (5) Hg0*+Q→Hg+Q, (6) Hg0*→Hg (by collisions with a wall). The respective values of cross-sections (σ2) of N2, CO, and NO for process (3) are ≤0.03, 0.60, and 20 Å2, and those for process (4) are 0.36, 2.1 and 5 Å2, and those for process (5) are ≤3.6×10−4, 0.15 and 8.0 Å2.
Conformation of Adsorbed Polymeric Chain. IV
Authors: Motomura Kinsi , Moroi Yoshikiyo , Matuura Ryohei 
Published: July 2006

Abstract
In order to develop further the theoretical treatment of a polymeric chain adsorbed at an interface, a random walk model, in which each step has the same probability except that no step can retrace the preceding one on a simple cubic lattice, has been used. The average number of adsorbed segments \barν, the average number of trains \barm, and the mean square end-to-end distance \barr2 are calculated as functions of the adsorption energy of segment ε and the number of segments n when n is infinitely large. The average numbers of segments in a train and a loop, \bark′ and \bark′, are also calculated. Through the increment in the value of critical adsorption energy εc, prohibition of immediate reversal for the random walk fairly influences the average properties of adsorbed polymeric ,chain. The decrease in \barm and the increase in \bark′ with ε⁄kT at its large values are remarkable in comparison with those of the symmetric random walk, which may be accounted for by the diminution of the chance of making loops. It is shown that \barr2 is equivalent to the mean square two-dimensional end-to-end distance of a restricted random walk without immediate reversals on a simple cubic lattice at εc⁄kT and approaches that on a simple square lattice in the limit ε⁄kT→∞.
The Reactions of Aroyl Peroxides with Grignard Reagents. II. Relative Reactivities of Substituted Benzoyl Peroxides
Authors: Okubo Masao , Maruyama Kazuhiro , Osugi Jir\={o} 
Published: July 2006

Abstract
Benzoyl peroxide was found to react with Grignard reagents (RMgBr) in tetrahydrofuran at 0°C to form PhCOOR and PhCOOMgBr. The latter which was isolated as a complex containing two molecules of the solvent, can be coordinated by benzoyl peroxide to form an orange-colored complex. Similar complexes were found to be formed in the cases of some substituted benzoyl peroxides. The initial stage of the reaction was studied with the technique of competitive reaction. The results can be explained by assuming the coordination of the carbonyl oxygen atom of benzoyl peroxide to the Grignard magnesium atom. The effect of the substituent of the peroxide on the reaction was discussed.
The Thermodynamic Properties of the Nonstoichiometric Ceric Oxide at Temperatures from 900 to 1300°C
Authors: Iwasaki Bunji , Katsura Takashi 
Published: July 2006

Abstract
Oxygen partial pressure in equilibrium with nonstoichiometric ceric oxide of a definite composition were determined by equilibration with pure oxygen, air, CO2, and CO2-H2 mixtures at 900, 1000, 1100, 1227, and 1300°C, using a thermobalance. The values for the activities and the relative partial enthalpies and entropies of both Ce2O3 and CeO2 were calculated on the basis of the relation between the Po2 and its composition.
The Zinc Bromide-catalyzed Rearrangement of Pulegone Oxide and Piperitone Oxide
Authors: Watanabe Hajime , Katsuhara Jun , Yamamoto Noriyuki 
Published: July 2006

Abstract
The rearrangement of (+)-cis- (I) and (−)-trans-pulegone oxide (II) was effected by the catalysis of zinc bromide in boiling benzene to give the same (−)-2,2,5-trimethylcyclohepta-1,3-dione (III), with a retention of the optical activity. The structure of (−)-III with the expanded 7-membered ring was confirmed by the chemical transformation into 1,1,4-trimethyl-cycloheptane(IV), which was identical with that derived from eucarvone(V). Piperitone oxide(VIII) was also converted into diosphenol(X) in the same manner as in pulegone oxides.
Reactions of Allenes. IV. New Palladium Complexes Having a Bridged Allene Trimer Ligand
Authors: Okamoto Tadashi 
Published: July 2006

Abstract
Di-μ-acetato-[2,2′-(1-methyleneethylene)bis-π-allyl]dipalladium (I) was obtained (18%) by the reaction of allene and palladium acetate. Its structure was estimated from the data of elemental analysis, molecular weight, hydrogenolysis reaction, IR, and NMR. Complex I was synthesized otherwise by the reaction of allene with di-μ-acetato-2,2′-bi-π-allyldipalladium. The insertion mechanism for the latter reaction was confirmed by the product of the reaction using allene-d4, Pd2(C9H8D4)(CH3COO)2. It was found that this insertion reaction was by far faster than analogous reactions with bis(acetylacetonato)-2,2′-bi-π-allyldipalladium or di-μ-acetato-bis-(π-allyl palladium). The observed acceleration was assumed to be due to strain in the substrate. From NMR data of I and other π-allylpalladium complexes already published, it was shown that the difference in chemical shifts between syn and anti protons of π-allyl complexes is dependent on the substituents on the central carbon; the nonconjugated substituents give smaller values (0,9–1.01 ppm for μ-chloro complexes), and α,β-unsaturated substituents give larger values (1.27–1.28 ppm for μ-chloro complexes). Chloro and acetylacetonato derivatives of I, and the activation energy for spin exchange of saturated methylene protons in I are also described.
Peptide Synthesis by Oxidation-Reduction Condensation. II. The Use of Disulfide as an Oxidant
Authors: Matsueda Rei , Maruyama Hiroshi , Ueki Masaaki , Mukaiyama Teruaki 
Published: July 2006

Abstract
A peptide synthesis starting from free N-protected amino acid and free amino acid ester by the use of triphenylphosphine, an oxygen acceptor, and disulfide, a hydrogen acceptor, was studied. The oxidation-reduction condensation reaction affords peptides with high optical purity in excellent yields by simple procedure.
The Water Structure Model of Narten et al. and the Pressure Effect on Sound Absorption in Water
Authors: Nomoto Otohiko , Endo Harumi 
Published: July 2006

Abstract
The mechanism of the temperature dependence of ultrasonic absorption in water under atmospheric pressure has hitherto been studied by means of the two-state-model theory of water. For an explanation of the pressure dependence of ultrasonic absorption by the two-state model, however, we are obliged to adopt the contradictory assumption that the open-packed structure of water has a higher energy than the more close-packed one. In order to avoid this contradictory assumption inherent in the two state-model theory, we have here employed the water model recently proposed by Narten et al. on the basis of X-ray scattering analysis. Although the calculation based on the Narten-model succeeds in explaining the pressure dependence of the ultrasonic absorption without the above-mentioned contradictory assumption, the structual compressibility (βst) thus obtained is about two times larger than the most reasonable value. The origin of this discrepancy seems to be that the Narten model of water considers the framework of the ice-1 lattice to be of infinite extent, without any boundary. By assuming the cluster-structure to be of a finite size, we can reduce βst to a reasonable value in agreement with the experimental results. The water cluster is found to be about eight molecules in diameter at 4°C.
The Activity of Dilute Sodium in Liquid Au-Na Alloy
Authors: Hirota Kazushi , Katsura Takashi 
Published: July 2006

Abstract
The electromotive force of the cell;
Au–Na alloy |Na2CO3| CO2+O2, Pt-Rh,
was determined as a function of the temperature and the concentration of sodium in the alloy. The results were consistent with the activity values determined previously by the equilibrium method. The overpotential due to the current passing through the Au–Na alloy surface is less than 1 mV per mA/cm2 of the current density at 1400°K. The activity of sodium, referred to the pure liquid standard state, was calculated from the electromotive force of this cell. The activity coefficient of sodium in Au–Na alloy is:
logγNa=−2.55⁄T·10−3+0.39±0.05
in the temperature range from 1250°K to 1500°K and in the concentration range of less than 10 atom%Na.
Preparation of Hydroxoaquo- and Diol-Type Cobalt(III) Complexes with Analogues of Nitrilotriacetic Acid
Authors: Uehara Akira , Kyuno Eishin , Tsuchiya Ryokichi 
Published: July 2006

Abstract
The following hydroxoaquo- and diol-type cobalt(III) complexes were prepared: K[Co(OH)(α-abda)(H2O)]·2H2O (I), K[Co(OH)(vda)(H2O)]·1.5H2O (II), K[Co(OH)pgda(H2O)] (III), K2[nipda Co(OH)2Co nipda]·2H2O (IV), K2[(α-abda) Co(OH)2Co (α-abda)]·3H2O (V), K2[vda Co(OH)2Co vda]·3H2O (VI), K2[lda Co(OH)2Colda]·2H2O (VII) and K2[pgda Co(OH)2Co pgda]·2H2O (VIII), where α-abda, vda, pgda, nipda and lda are the abbreviations of d,l-α-amino-n-butyric-N,N-diacetate, l-valine-N,N-diacetate, d-α-phenylglycine-N,N-diacetate, nitriloisopropionicdiacetate and l-leucine-N,N-diacetate ions, respectively. From the measurements of electronic spectra, conductivities and coagulation values and the results of derivatography, it was found that the diol complexes IV–VIII were also formed from the correspoindng hydroxoaquo complexes in the thermal reaction process.