bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lifetimes of Electrons in Irradiated Liquid Alkanes
Authors: Fueki Kenji 
Published: July 2006

Abstract
A calculation has been made of lifetimes of electrons in irradiated liquid alkanes on the basis of the lifetime distribution function for the geminate electrons derived from the exponential distribution function for electron ranges. The results show that the intrinsic electron lifetimes correlate with the electron mobilities and most of the geminate electrons recombine within 1 ns in the alkanes at room temperature. A consideration is given to the effect of pulse duration time on the apparent electron lifetime and the observable yield of electrons in n-hexane.
The Micelle Formation of Alkylammonium Chloride in 1-Propanol–Water and Acetone–Water Mixtures
Authors: Miyagishi Shigeyoshi 
Published: July 2006

Abstract
The change in the critical micelle concentrations (CMC) of alkylammonium chlorides (C12–C18) and in the degree of the dissociation of the micelle (α) of dodecylammonium chloride was determined by adding 1-propanol and acetone to water. Both the CMC and the α increased with an additive concentration, each reaching a maximum at a certain concentration (critical composition of solvent for micelle formation, CCSM) and decreasing beyond the CCSM. The increment in the CMC was more influenced by the alkyl-chain length in the surfactant molecule in the presence of 1-propanol than in that of acetone. The effective coefficient of electrical energy (Kg) and the cohesive energy difference per methylene group between the micelle and the monomer states (ω) were calculated from the CMC and the α. The Kg values in both mixed solvents were constant beyond the respective CCSM. The value of ω was less in the presence of 1-propanol than in that of acetone.
Ultrasonic Absorption Mechanisms in Aqueous Solutions of Alcohols
Authors: Nishikawa Sadakatsu , Mashima Mitsuo , Maekawa Michio , Yasunaga Tatsuya 
Published: July 2006

Abstract
Ultrasonic absorption measurements in aqueous solutions of tert-butyl and allyl alcohols were carried out in the frequency range of 4.5–220 MHz at 25 °C. Two relaxation processes were observed in aqueous solution of tert-butyl alcohol and a single one in that of allyl alcohol. The former relaxation mechanisms were revealed to be due to the perturbation of the equilibria expressed by (Remark: Graphics omitted.) where A and B were alcohol and water molecule respectively. The latter mechanism was due to that expressed by (Remark: Graphics omitted.). The rate constants for all these processes were determined from the concentration dependence of the relaxation frequencies. The water structure in aqueous solutions was discussed in terms of a hydrophobic interaction, and it was concluded that the hydrophobic interaction decreased in this sequence, tert-butyl, n-propyl and allyl alcohols.
Non-isothermal Studies of Adduct Molecules of Metallic Halides with Oxo-Compomids in Solid State. I.
Authors: Chaudhuri N Ray , Mitra S , Pathak G K 
Published: July 2006

Abstract
Non-isothermal studies of some adduct molecules of metallic halides with dioxane as the type MX2·y(dioxane) in;solid state, where M=Mn(II), Co(II), Ni(II), Cu(II), Zn(II) or Cd(II), X=Cl− or Br− and y=0.5–2, were carried out with a Derivatograph. These inorganic adduct molecules lose dioxane molecule in single or multiple steps on heating. Thermally stable intermediate products were isolated and characterised by elemental analysis and IR spectra. The activation energy for each step of decomposition of the adduct was evaluated from the analysis of TG, DTG and DTA curves. Enthalpy change was evaluated from the DTA peak area and the order of reaction was found to be unity for each step of decomposition. Thermal stability of the adducts was discussed.
Energy Difference between Rotational Isomers of 1,2-Dibromoethane
Authors: Hiraishi Jiro , Shinoda Takako 
Published: July 2006

Abstract
The energy difference between the rotational isomers of 1,2-dibromoethane in the liquid state was determined to be 910±80 cal/mol on the basis of the relative intensity of the Raman band at 660 cm−1 (trans form) to that at 551 cm−1 (gauche form) in the temperature range from 24.5 to 105.1 °C.
Photoelectron Spectroscopic Study of Skew Compounds. III. N,N′-Dimethylhydrazine, Dimethyl Peroxide, and Dimethyl Disulfide
Authors: Kimura Katsumi , Osafune Kazuteru 
Published: July 2006

Abstract
He I photoelectron spectra of CH3HNNHCH3, (CH3)2O2, and (CH3)2S2 have been measured and the spectra below 18 eV have been resolved into nine ionization bands corresponding to p-type localized molecular orbitals. Orbital assignments of the resulting vertical ionization energies have been carried out with CNDO/2 calculations in which orbital energies were calculated as a function of the dihedral angle in the region 0–180°. The separation of the nonbonding photoelectron bands suggests that CH3HNNHCH3 exists in outer-inner skew form, whereas (CH3)2O2 is in trans form. The sum rule consideration previously proposed by the present authors has been applied to the compounds studied here. The total sum of the vertical ionization energies in the p-type region for each compound has been well reproduced in terms of appropriate empirical parameters based on the photoelectron spectra of simple molecules. The effects of methyl substitution on the ionization-energy total sums for N2H4, H2O2, and H2S2 have been found to be very similar to those for ethane and ethylene.
The Enthalpy of Vitreous Beryllium Fluoride
Authors: Tamura Seiichi , Yokokawa Toshio 
Published: July 2006

Abstract
The enthalpy increments of beryllium fluoride were measured by the drop method in the glassy and liquid states from 450 to 914 K. The other thermodynamic functions were also calculated. The estimated configurational entropy of the supercooled liquid showed its temperature dependence to be small compared with those of nearly all other glass-forming liquids. The theory of Adam and Gibbs was applied to explain both the present enthalpy data and the Arrhenius viscosity behaviour over an unusually wide temperature range. The similarity between beryllium fluoride and silicon dioxide was also shown with respect to the heat capacities of the glassy and supercooled liquid states.
The Acid-catalyzed Reaction of Cycloalkanones with Formaldehyde
Authors: Hirano Fukumi , Wakabayashi Shoji 
Published: July 2006

Abstract
The acid-catalyzed reactions of several cycloalkanones, such as cyclopentanone (1a), 2-methylcyclopentanone (1b), cyclohexanone (1c), 2-methylcyclohexanone (1d), and 2-isopropyl-5-methylcyclohexanone (1e), with formaldehyde were investigated. These reactions involved an aldol condensation analogous to the Prins reaction, and they afforded methylol derivatives and cyclic ethers. It was found that the formation of the products is strongly influenced by the skeletal structure and by the substituent on the cycloalkanones. That is, 1a, 1c, and 1d gave mainly 1,3-dioxanes, while 1b and 1e formed only methylol derivatives. The reaction of cycloalkanone enol esters with formaldehyde was also studied.
Studies on the Ruthenium Complexes. IX. Kinetic Studies on the Deaquation-anation Reaction of Aquapentaammineruthenium(III) Complexes
Authors: Ohyoshi Akira , Hiraki Shun-ichi , Odate Tomio , Kohata Susumu , Oda Junko 
Published: July 2006

Abstract
The deaquation-anation reaction of [Ru(OH2)(NH3)5]X3-type complexes in the solid state, as shown by the [Ru(OH2)(NH3)5]X3(s)→[RuX(NH3)5]X2(s)+H2O(g) equation, where X is Cl, Br, I, and NO3 respectively, was kinetically studied by means of thermogravimetry (TG) along with differential thermal analysis (DTA). The activation energy and entropy in the reaction process (Ea kcal/mol, ΔS\eweq e.u.) are, respectively, found by isothermal kinetic study to be (22.7, −7.1) for the chloride, (23.4, −5.2) for the bromide, (26.7, 5.8) for the iodide, and (19.3, −15.9) for the nitrate. The reaction seems to proceed through the following two steps, except in the case of the iodide: [Ru(OH2)(NH3)5]X3→[RuX(OH2)(NH3)5]X2→[RuX(NH3)5]X2+H2O. The first step is regarded as the rate-determining one.
Ion Association of Some 2 : 2 Electrolytes in Water at 25 °C. II. Spectrophotometric Studies of the Ion Association of Magnesium, Calcium, Manganese, Copper, and Zinc Sulfates
Authors: Yokoyama Haruhiko , Yamatera Hideo 
Published: July 2006

Abstract
Simple and mixed aqueous solutions of copper, magnesium, calcium, manganese, and zinc sulfates were spectrophotometrically studied in order to obtain the ion-association constants of the divalent metal ions with the sulfate ion. The ion-association constant of copper sulfate was obtained from the measured absorbances of copper sulfate solutions at 250 nm as a function of the closest distance of approach of ions. For the other metal sulfates which show a negligible absorption at 250 nm, absorbances were measured on the mixed solutions with copper sulfate, and the results were analyzed by the use of the results on copper sulfate in order to obtain the ion-association constants. The best values of the ion-association constant and the closest distance of approach were determined for each metal sulfate with the help of the theory of ion association. The results were compared with those obtained from the measurements of osmotic coefficients and electric conductivities. The numerical results are summarized in Table 6 of the text.
Metachromasy. III. Metachromatic Behavior of Trypaflavine in the Presence of Polyphosphates with Various Chain Lengths
Authors: Yamaoka Kiwamu , Takatsuki Mineo , Miura Masaji 
Published: July 2006

Abstract
The interaction of trypaflavine with sodium polyphosphate in aqueous solutions in the pH range 6–7 has been investigated by means of light absorption spectroscopy, conductometric titration and ultrafiltration. The metachromatic behavior of the bound dye was characterized in terms of hypso- and hypochromic effects in both visible and UV regions where no pronounced metachromasy band was observed. The effects were studied by varying the mixing ratio of polymer residue to dye, P/D, from 0.1 to 10000. They were found to be maximum in the P/D range 2–10. The effect of the chain length of polyphosphate on metachromasy was determined by use of fourteen refractionated samples with the degree of polymerization, \barn, ranging from 8 to 158. No metachromasy appeared in samples with \barn&lt;7. It fully developed for those with \barn&gt;20, sharply depending on the chain length between 7 and 20. By conductometric titration and ultrafiltration, it was verified that the dye binds to the ionized phosphate almost at 1 : 1, and that the disappearance of metachromasy with the increase in P/D values or with the addition of salts results from two entirely different processes. The results were compared with the data for other dyes.
Soret Coefficients and Heat of Transport of Polyvalent Electrolytes in an Aqueous Solution
Authors: Sugisaki Masayasu 
Published: July 2006

Abstract
The Soret coefficients of aqueous electrolytes were measured by the conductometric method for salts of K2SO4, Na2SO4, ZnSO4, and CdSO4 in the concentration range from 0.001 to 0.01 M at 25 °C and 35 °C. The heats of transport were calculated from the Soret coefficients. The concentration dependence of the heat of transport was ascertained to be proportional to the square root of the ionic strength, and the slopes for Na2SO4 and K2SO4 salts at 25 °C were found to be larger than those reported by Snowdon and Turner. The temperature dependence of the heat of transport was examined based on the data at 25 °C and 35 °C. The heat capacities concerning the transported entropy were found to be negative for the four salts examined.
Molecular Reorientational Motion of the Benzene Molecule in a Mixture of Benzene with Carbon Tetrachloride by Raman Band Spape Analysis
Authors: Nomura Hiroyasu , Miyahara Yutaka 
Published: July 2006

Abstract
The reorientational correlation times of the benzene molecule in mixtures of benzene with carbon tetrachloride were measured by the method of the Raman line shape analysis. The reorientational relaxation times τor of C6H6 in solutions increased with increasing mole fraction of CCl4. Information was also obtained on an intermolecular vibration-vibration energy transfer process which primarily affects the mean life time of the first excited vibrational state ν2 (a1g) in benzene in solutions.
Total Synthesis of (±)-Tetrahydroligularenolide
Authors: Tatee Tochiro , Takahashi Takeyoshi 
Published: July 2006

Abstract
A total synthesis of (±)-tetrahydroligularenolide [(±)-2] is described. 10β-Methyl-5β-tetrahydropyranyloxy-trans-2-decalone (6) was converted in seven steps into 3-methoxycarbonyl-5,10-dimethyl-trans-2-decalone (15), which on alkylation with ethyl α-iodopropionate gave 3-(1-ethoxycarbonylethyl)-3-methoxycarbonyl-5,10-dimethyl-trans-2-decalone (19) and 6-(1-ethoxycarbonylethoxy)-7-methoxycarbonyl-1β,8aβ-dimethyl-1,2,3,4,4a,5,8,8a-trans-octahydronaphthalene (20). Hydrolysis of 19 proceeded with a loss of carbon dioxide to afford (±)-tetrahydroligularenolide [(±)-2].
Metal Chelates of 9-Hydroxy-1-phenalenone
Authors: Demura Yoichi , Kawato Toshio , Kanatomi Hajime , Murase Ichiro 
Published: July 2006

Abstract
Metal chelates of 9-hydroxy-1-phenalenone(9-hydroxyperinaphthenone) have been prepared. Metalligand compositions were 1:2 for Cu(II), Ni(II), Co(II), Mn(II), Zn(II), Mg(II), UO2(II), and Be(II) chelates and 1 : 3 for Fe(III) and Al(III) chelates. The structure of the Cu(II) chelate was determined to be squareplanar by the spectral analogy to copper(II) acetylacetonate. The Ni(II), Co(II), Mn(II), Zn(II), and Mg(II) chelates were octahedral with further coordination of two moles of water. The structure determination dealt at first with the Ni(II) chelate by means of its electronic spectrum and magnetic property; the others were studied using the similarity of their X-ray diffraction diagrams to that of the Ni(II) chelate. The Fe(III) and Al(III) chelates were also octahedral and probably have D3 symmetry. Infrared spectra were studied for the free ligand and the metal chelates and the assignment of the carbonyl and metal-oxygen stretching vibrations was discussed by comparison with those of metal acetylacetonates.
Synthesis of 2,3,6,7-Tetramethylnaphthalene from 2,3-Dimethylsuccinic Anhydride and o-Xylene
Authors: Dozen Yasuhiko , Hatta Masato 
Published: July 2006

Abstract
2,3,6,7-Tetramethylnaphthalene (7b) was prepared from 2,3-dimethylsuccinic anhydride (1) and o-xylene in five steps, and the configurations of their intermediates were studied. The higher-melting isomer (threo form) of 1 gave higher-melting products in each step, while the lower-melting isomer (erythro form) of 1 gave lowermelting ones. The configurations of the intermediates were confirmed by the MNR spectral data of tetramethyltetralines (6b). Similar reactions were carried out with 3-benzoyl-2,3-dimethylpropionic acid (2a) in order to learn the configurations of the intermediates. 3-Aroyl-2,3-dimethylpropionic acids (2) gave 2,3-dimethyl-4-aryl-3-buten-4-oildes (3) upon heating with hydrochloric acid.
Electroorganic Chemistry XVIII Anodic Oxidation of Substituted Cyclopropanes
Authors: Shono Tatsuya , Matsumura Yoshihiro 
Published: July 2006

Abstract
The anodic oxidations of polyalkyl-substituted cyclopropanes (1–3) and spiro[2.n]alkanes (4–6) were carried out in methanol. Monomethoxyolefin and dimethoxy compound resulted from the selective cleavage at the most substituted carbon–carbon bond. The decrease in the oxidation potential brought about by the substitution of the one methyl group was observed to be about 0.3 V vs. SCE. The analysis of the products and oxidation potentials of the cyclopropanes suggested that the σ-electron transfer from cyclopropane to the anode may be the initiation process and that the stereochemistry at the surface of the solid electrode plays an important role in this anodic oxidation.
Circular Dichroism in Lyotropic Liquid Crystals of Polyglutamate Solutions
Authors: Tsuchihashi Nobuaki , Nomori Hiroyuki , Hatano Masahiro , Mori Shigeo 
Published: July 2006

Abstract
A poly-γ-ethyl-l-glutamate solution with a cholesteric color exhibits a circular dichroism due to the selective reflection of circularly polarized light of one sense by the cholesteric helical structure existing in the solution. On the other hand, an induced circular dichroism is observed in the wavelength region corresponding to the absorption bands of an achiral dye molecule when the molecule is dissolved in the poly-γ-benzyl-d-glutamate liquid crystalline phase. The two modes of circular dichroism are correlated to the structure and the chirality of the cholesteric phase of concentrated polyglutamate solutions.
Sesquiterpenes from Acorus calamus L.
Authors: Niwa Masatake , Nishiyama Atsuko , Iguchi Masanobu , Yamamura Shosuke 
Published: July 2006

Abstract
Three new sesquiterpenes, acoragermacrone (1), acolamone (2), and isoacolamone (3) were isolated from Acorus calamus L., and their structures were elucidated. In particular, acoragermacrone, a ten-membered ring sesquiterpene, is the most important precursor of the other sesquiterpenes included in the same plant. Acoragermacrone was converted into shyobunone, epi-shyobunone, preisocalamendiol, acolamone, and isoacolamone.
A Study of Optically Active (Benzoin-α-oxime)dichlorocopper(II)
Authors: Kudo Tomikatsu , Kaizaki Sumio , Hidaka Jinsai , Shimura Yoichi 
Published: July 2006

Abstract
An optically active complex, [(S)-benzoin-α-oxime]dichlorocopper(II), was prepared and its absorption and circular dichroism spectra were investigated in organic solvents.
A Structural Investigation of the 2-Methylthiophene Trimer and Its Related Compounds
Authors: Ishigaki Akira , Shono Toshiyuki 
Published: July 2006

Abstract
A structural investigation of the 2-methylthiophene trimer and its crystalline oxidation product has been performed. These compounds have been found to be identical with 2,4-bis(5′-methyl-2′-thienyl)-2-methylthiolane and its sulfone derivative.
Uranyl Ion-Sensitized Isomerization of the Stilbenes in Solution
Authors: Matsushima Ryoka , Kishimoto Tsuneo , Suzuki Morio 
Published: July 2006

Abstract
By selective excitation of the uranyl ion with light of λ≥365 nm, a deoxygenated acetone solution containing cis- or trans-stilbene and the uranyl ion finally reaches a photostationary state, whose isomer ratio, (t⁄c)pss, varies from 1 to 3 depending on the concentrations of the uranyl ion and the stilbenes. A close correlation is found between the features in the sensitized isomerization and the phosphorescence quenching of the sensitizer. Comparison with the results of halogen radical induced isomerization suggests that catalytic isomerization by free radicals is not an important process. A triplet-triplet energy transfer mechanism is proposed, which is supported by the oxygen effect and considerations on the lowest excited state of the uranyl ion, i.e., its long lifetime and triplet energy level higher than that of the stilbenes.
An Adiabatic Calorimeter for High-resolution Heat Capacity Measurements in the Temperature Range from 12 to 300 K
Authors: Tatsumi Masami , Matsuo Takasuke , Suga Hiroshi , Seki Syûzô 
Published: July 2006

Abstract
Construction of a high resolution calorimeter of an adiabatic type for single crystals is described. It uses a bank of thermistors for high resolution measurements in addition to a miniature platinum resistance thermometer. The results of heat-capacity measurements on benzoic acid as a standard material showed the inaccuracy of ±0.1% and the imprecision was confirmed to be less than ±0.05% between 50 and 275 K.
Photochemistry in the Adsorbed Layer. VI. The Type I Selectivity in the Photolysis of Adsorbed 2-Pentanone
Authors: Anpo Masakazu , Kubokawa Yutaka 
Published: July 2006

Abstract
A marked high selectivity of the type I reaction in the photolysis of adsorbed 2-pentanone decreases with increasing amount of 2-pentanone adsorbed, approaching the selectivity in the water solution photolysis. In the solution photolysis the type I selectivity decreases in the order water&gt;methanol&gt;n-heptane. From these results together with comparison of the blue shifts of the (n,π*) bands in solution and in the adsorbed layer it has been concluded that such an enhancement of the type I reaction in the adsorbed layer is attributed to a heterogeneity of the surface, i.e., the presence of special active sites, as well as to the surface polarity.
Effects of Foreign Gases on Dual Fluorescences of Pyrene Vapor
Authors: Chihara Kohji , Baba Hiroaki 
Published: July 2006

Abstract
The characteristics of the dual fluorescences of pyrene vapor at 170 °C and 0.2–0.3 Torr have been investigated in the presence of cyclohexane or oxygen. With increasing cyclohexane pressure, the S1-fluorescence shows a blue shift and an increase in quantum yield and in lifetime, while the S2-fluorescence shows only a slight blue shift and a marked decrease in yield and in lifetime. Oxygen efficiently quenches the S1- and S2-fluorescence according to the Stern-Volmer relation. The experimental results are well explained by kinetic analyses based on the following assumptions: (1) The internal conversion is reversible and is much faster than other radiative and radiationless processes; (2) cyclohexane causes only vibrational relaxation which can be described in terms of a simple stepladder model; (3) oxygen acts as a quencher on both S1- and S2-fluorescence emissions. It is found that one collision with cyclohexane removes on the average a vibrational energy of the order of 1000 cm−1 or less from S1 or S2 of pyrene, and that one collision with oxygen quenches S1 or S2 with a probability close to unity. It is concluded that the S2-fluorescence consists mainly of a slow component originating from S2 which is in equilibrium with S1.
Vapor-Phase Photolysis of cis- and trans-4,5-Dimethylcyclohexenes
Authors: Inoue Yoshihisa , Takamuku Setsuo , Sakurai Hiroshi 
Published: July 2006

Abstract
Direct and sensitized photolyses of 4,5-dimethylcyclohexene vapor were investigated using a stereochemical approach at room temperature over the pressure range from 1 to 9 Torr. In the direct photolysis, decomposition of the retro-Diels-Alder type was the main course of the reaction, leading to the formation of 2-butene and 1,3-butadiene with the retention of the original configuration; 3,4-dimethyl-1-methylenecyclopentane was also formed as a minor product from a pressure-independent process. Mercury sensitization, on the other hand, produced cis- and trans-2-butenes, butadiene, 2,3-dimethyl-1-vinylcyclobutane, and cis-trans isomers of the substrate together with radical-induced products, i.e., hydrogen, 1,2-dimethylcyclohexane, and dimeric products. The intermediacy of a “hot,” “triplet” biradical was suggested from the pressure-dependence of the trans- to cis-2-butene ratio in the mercury sensitization. The differences in the results between the direct and sensitized photolyses are interpreted in terms of spin correlation effects.
Electronic Spectra of Tetraphenylporphinatoiron(III) Methoxide
Authors: Kobayashi Hiroshi , Higuchi Tadatoshi , Kaizu Youkoh , Osada Hisajiro , Aoki Masaru 
Published: July 2006

Abstract
Tetraphenylporphinatoiron(III) methoxide in the high-spin state S=5⁄2 gives rise to an absorption spectrum which has been assigned to that of low-spin iron(III) porphyrins. The excited states characteristic of the spectrum of high-spin iron(III) porphyrins are the configuration-interaction admixtures of the lowest triplet and singlet porphyrin (π,π*) excited states and the low-lying “porphyrin to iron (III)” charge-transfer excited states. The charge-transfer excited states in tetraphenylporphinatoiron(III) methoxide, however, are so high that the chargetransfer excited states are not sufficiently mixed with the lowest triplet (π,π*) excited states. Thus the high-spin methoxo complex does not exhibit a spectrum characteristic of high-spin iron(III) porphyrins.