bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ionic Motion and Phase Transition in Potassium Hydrogendifluoride KHF2 Studied by Pulsed NMR
Authors: Furukawa Yoshihiro , Kiriyama Hideko 
Published: July 2006

Abstract
Nuclear spin-lattice relaxation times, T1 and T1ρ, have been measured above room temperature for 1H and 19F nuclei in powdered KHF2 and its deuterated analogue. Below 400 K and in the high-temperature β-phase (Tt=469.8 K), the magnetization recovery for both nuclei in KHF2 is strongly non-exponential owing to the heteronuclear H–F interaction. In the low-temperature α-phase the T1 vs. 1/T curves show broad minima ascribable to the 180°-flip motion of linear [FHF]− anions. The activation energy Ea of this motion was determined to be 50.5±2 kJ/mol. The phase transition, which is defined by discontinuous changes in both T1 and T1ρ, is associated with diffusional disorder superimposed on rapid isotropic reorientation of the HF2− ion. The relaxational process in the β-phase is governed by self-diffusion of the anions with an Ea of 80±6 kJ/mol deduced from the T1ρ data. In contrast to the earlier suggestion from electrical measurements, the NMR results indicate that the dominantly mobile species in the conducting high-temperature β-phase are not single F− ions but complex [FHF]− anions.
Photoelectron Angular Distribution Measurements for Some Pyridines
Authors: Utsunomiya Chikatoshi , Kobayashi Tsunetoshi , Nagakura Saburo 
Published: July 2006

Abstract
The angular distributions for the He I photoelectron spectra of pyridine, pentafluoropyridine, and 2,6-lutidine have been measured in order to solve the ambiguities on the band assignment of pyridine. It has been concluded that the first band of pyridine is assigned to the a1n orbital and the fifth band to the lowest occupied b1π orbital.
Synthesis of 6-Hydroxy-12-methyl-7,12-dihydrobenzo[6,7]cyclohept[1,2-b]indol-7-one
Authors: Fujimori Kunihide , Yamane Kameji 
Published: July 2006

Abstract
5,6,7,12-Tetrahydrobenzo[6,7]cyclohept[1,2-b]indol-7-ones were obtained by the oxidation of 5,6,7,12-tetrahydrobenzo[6,7]cyclohept[1,2-b]indoles with 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) in wet dioxane. The α,α-dibromo compound, obtained by bromination of 12-methyl-5,6,7,12-tetrahydrobenzo[6,7]cyclohept[1,2-b]indol-7-one with phenyltrimethylammonium tribromide (PTAB), was hydrolyzed to give the diketone (5). By treatment with alkali, compound 5 was converted to 6-hydroxy-12-methyl-7,12-dihydrobenzo[6,7]cyclohept[1,2-b]indol-7-one.
5,9-Dihydroxy-4,8,11,11-tetramethyltricyclo[6.3.0.02,4]undecane. Acidcatalyzed Cyclization Product of 6,7-Epoxyhumula-2,9-diene
Authors: Namikawa Misuzu , Murae Tatsushi , Takahashi Takeyoshi 
Published: July 2006

Abstract
6,7-Epoxyhumula-2,9-diene (2) was treated with 1.8 M sulfuric acid–acetone (1 : 1) to yield a new tricyclic diol, 5,9-dihydroxy-4,8,11,11-tetramethyltricyclo[6.3.0.02,4]undecane (9; diol B), together with tricyclohumuladiol (3; diol A), humulenol-II (4), a diol C (5b), a diol D (5a), and an acetonide (8a). The same reaction at 0° gave only 3. Tricyclohumuladiol (3) was shown to be a key intermediate in the reaction of 2 to form 4, 5a, 5b, 8a, and 9.
Intramolecular Dimer and Excimer Phosphorescence of Poly(2-vinylnaphthalene) and Copolymers of 2-Vinylnaphthalene and Phenyl Vinyl Ketone
Authors: Aikawa Masayuki , Takemura Takeshi , Baba Hiroaki , Irie Masahiro , Hayashi Koichiro 
Published: July 2006

Abstract
Phosphorescence spectra and lifetimes of poly(2-vinylnaphthalene) and copolymers of 2-vinylnaphthalene and phenyl vinyl ketone have been measured as a function of the composition ratio between the constituent benzoyl and naphthyl groups in both rigid and fluid solutions.
Preparation and Electrical Conductivity of Some Simple and Complex Salts Formed between N,N-Dialkyl-1,3-dichalcogena-cycloalkan-2-iminium and TCNQ\ewdot
Authors: Araki Shingo , Ishida Hiromi , Tanaka Toshio 
Published: July 2006

Abstract
Four simple salts and six complex salts of TCNQ\ewdot radical anion with N,N-dialky1-1,3-dichalcogenacycloalkan-2-iminium cations, (Remark: Graphics omitted.) and (Remark: Graphics omitted.) (n=2 or 3, Y=S or Se, R=Me or Et) were prepared. The electrical resistivity of (Remark: Graphics omitted.) (1.1×104 ohm cm) was more than 10 times lower than other three simple salts ((6.1–8.7)×105 ohm cm). Electronic absorption spectra and magnetic susceptibilities suggest that the latter three involve dimeric (TCNQ)22−, while in the former the interaction between two TCNQ\ewdot radical anions is weak in the solid state. All the complex salts with compaction samples exhibited the resistivity of 2.4–4.0 ohm cm with very low activation energies (0.018–0.087 eV). Electronic spectra and magnetic susceptibilities show that the interaction between two TCNQ\ewdot radical anions decreases owing to the implication of neutral TCNQ.
The Use of Solvent ET-values in High Pressure Kinetics
Authors: Jouanne Jörn von , Palmer Donald A , Kelm Hartwig 
Published: July 2006

Abstract
The solvatochromic shift and its pressure dependence of the charge transfer band of 2,4,6-triphenyl-pyridinium-N-(3,5-diphenyl-)phenol betaine (ET-values) have been measured together with partial molar volumes of the betaine in a number of solvents.
The Preparation and Some Properties of 3-Substituted 2,4-Pentanedionato Metal(II, III) Complexes
Authors: Kasuga Kuninobu , Anami Masao , Yamamoto Yasuo 
Published: July 2006

Abstract
In the substitution reactions of phenol, benzenethiol, and their sodium salts on the chelate ring of 3-bromo-2,4-pentanedionato metal complexes (metal=iron(III), aluminium(III), and beryllium(II)), benzenethiol was found to be substituted for bromine, while phenol was not substituted under the same conditions. In the case of sodium salts, both sodium phenoxide and benzenethiolate gave substituted products. The UV and PMR data of tris(3-substituted 2,4-pentanedionato)aluminium(III) complexes gave some information on the substituted groups.
The Crystal Structure of Guanidinium Hexamolybdobis(phenylarsonate) Tetrahydrate, (CN3H6)4[(C6H5As)2Mo6O25H2]·4H2O
Authors: Matsumoto Kazuko Y 
Published: July 2006

Abstract
Two heteropoly anions, [C6H5AsMo6O21(H2O)6]2− and [(C6H5As)2Mo6O25H2]4−, have been synthesized by the reaction of phenylarsonic acid with molybden um trioxide in an aqueous solution of pH ca. 2. The latter anion has been subjected to crystal-structure analysis as a guanidinium salt, (CN3H6)4[(C6H5As)2Mo6O25H2]·4H2O, and a heteropoly anion with a new type of structure has been established. The crystal is monoclinic with the space group of P21 and cell dimensions of a=13.754(5), b=15.752(7), c=11.900(5) Å, β=115.59(2)°, V=2325.3 Å3, Dm=2.25, Dx=2.28 g cm−3, and Z=2. The formula of the anion has been proved to be [(C6H5As)2Mo6O25H2]4−, which is different from the expected formula, [(C6H5As)2Mo6O24]4−, though the latter had previously been proposed on the basis of a 17O NMR study and an independent X-ray investigation of the methyl derivative had confirmed the existence of the [(CH3As)2Mo6O24]4− anion. The present anion, [(C6H5As)2Mo6O25H2]4−, consists of six MoO6 octahedra, which form a ring with one face-, two corner- and three edge-sharings, the two C6H5AsO3 tetrahedra are attached to the ring from above and below, with their three oxygens shared with molybdenums. The two phenyl groups are oriented upwards and downwards from the ring respectively.
Structural Assignment by NMR Analyses of N-(Diacylamino)imide Derivatives. Diels-Alder Adducts of 2,3-Dimethylnaphthalene and 6,6-Diphenylfulvene with Maleic Anhydride
Authors: Verma Shiva Mohan , Singh Ashok Kumar 
Published: July 2006

Abstract
The configurations of the Diels-Alder adducts of maleic anhydride with 2,3-dimethylnaphthalene and 6,6-diphenylfulvene have been investigated by NMR spectroscopy. Restricted rotation and non-planar conformations about the N–N bond in the corresponding N-aminoimide derivatives of the adducts have been employed in solving the structural problem. While the N′,N′-diacetyl system has been shown to be a suitable probe for configurational assignment, N′-acetyl-N′-aroyl-N′-aminoirnide derivatives have been found to be a more diagnostic probe even to simple adducts.
Low Temperature Photolysis of o-Benzoquinones. Spectroscopic Detection of Cyclopentadienones and Bis-Ketenes
Authors: Tomioka Hideo , Fukao Hiroshi , Izawa Yasuji 
Published: July 2006

Abstract
The photodecarbonylation of o-benzoquinone to cyclopentadienone at low temperature was monitored by infrared and ultraviolet spectra which showed that the reaction is highly sensitive to substituents. 3,5-Di-t-butyl-o-benzoquinone undergoes clean decarbonylation to give cyclopentadienone under irradiation at −170 °C. Similar irradiation of 4-t-butyl-, 4-methyl-, 3-methyl-, and unsubstituted o-benzoquinones also leads to decarbonylation to cyclopentadienones. However, competitive α-cleavage to bis-ketene becomes important in these systems. Direct spectroscopic observation of the elusive cyclopentadienone was unsuccessful because of the overlapping absorption of the by-product. The infrared spectrum of bis-ketene from 4-t-butyl-o-benzoquinone shows that it exists as a mixture of rotamers, not undergoing thermal interconversion even at −170 °C.
Chemical Modification of Neamine. 5. Preparation of Amino-deoxyneamines
Authors: Nishiyama Shigeru , Ishikawa Yasuhide , Yamazaki Masahiko , Suami Tetsuo 
Published: July 2006

Abstract
An aminocyclitol antibiotic neamine has been modified in its 2-deoxystreptamine moiety by converting the hydroxyl group into an amino group to give three antibiotic amino-deoxyneamines. Their antimicrobial activities were determined against several microorganisms.
Some Aspects on the Mechanism of Palladium-complex-catalyzed Decomposition of and Cyclopropanation with Ethyl Diazoacetate
Authors: Nakamura Akira , Koyama Teruhisa , Otsuka Sei 
Published: July 2006

Abstract
Carbenoid decomposition of ethyl diazoacetate in the presence of various palladium complexes as catalysts was found to kinetically depend on the identity of halide ligands. The use of several chiral ligands did not induce appreciable enantioselective catalytic cyclopropanation between ethyl diazoacetate and styrene. The active catalyst species is not under the influence of the chiral ligands but under control of halides which are bound more strongly to the metal.
The Hydrocracking of Polynuclear Aromatic Hydrocarbons over Molten Salt Catalysts
Authors: Nakatsuji Yohji , Kubo Toshio , Nomura Masakatsu , Kikkawa Sh\={o}ichi 
Published: July 2006

Abstract
The hydrocracking of phenanthrene, anthracene, pyrene, chrysene, and fluoranthene over molten salt catalysts at 400 °C in the batch autoclave systems was examined. The products were mainly identified by means of GC-MS, but the representative products were isolated by preparative GLC and characterized by using NMR, IR, UV, and mass spectrometry. Most of the isolated products are compounds not previously confirmed in detail, although their formation has been expected in the hydrocracking of the corresponding aromatic compounds. Probable reaction routes are offered based on the product distributions. The binary mixture of zinc chloride and copper(I) chloride is considered to act as a molten dual-functional catalyst.
A Simple Method for the Calculation of the Polycrystalline ESR Lineshape
Authors: Shimokoshi Kazuo 
Published: July 2006

Abstract
A simple interpolation method is developed for calculating the magnetic resonance lineshapes of the polycrystalline samples. The method uses the spline function with the optional number of calculated points, at which the spin Hamiltonian is solved most accurately. The calculation procedure and some examples will be given.
NMR Spectroscopic Studies of the Tautomerism in Tetramic Acid Analogs and Their Anilides. III. Polar Solvent Effects on the Tautomeric Populations
Authors: Saito Kimitoshi , Yamaguchi Tatsuaki 
Published: July 2006

Abstract
NMR spectroscopic studies of 3-acetyltetramic acid (3-acetyl2,4-azolidinedione), 3-acetyltetronic acid (3-acetyl-2,4-oxolanedione), 3-acetylthiotetronic acid (3-acetyl-2,4-thiolanedione) and their anilides (3-(2-phenyliminoethyl) derivatives) showed variations in the tautomeric equilibria with certain polar solvents. For example, the strong solvation effect of DMSO-d6 causes a predominance of the lactim forms of 3-acetyltetramic acid over the lactam forms and up-field shifts of the enolic protons.
The Microenvironmental Effect of Cyclodextrin on the Acid Dissociation of Some Azo Dyes in Aqueous Solutions
Authors: Matsui Yoshihisa , Moghida Kazuo 
Published: July 2006

Abstract
The effects of α- and β-cyclodextrins (CD) on the acid dissociations and tautomeric equilibria of sodium 4-(4′-hydroxy-1′-naphthylazo)-1-naphthalenesulfonate (1) and of the conjugate acid (2) of Methyl Orange were spectrophotometrically examined and were compared with the effect of a nonpolar solvent (THF). The apparent pKa values for the dyes decreased with increasing CD concentration. The effect of CD is mainly explained in terms of the hydrophobic interactions between the azo dyes and CD, resulting in a shift in the tautomeric equilibria from less acidic azonium or hydrazone forms to more acidic azo forms of 1 and 2 in an aqueous solution.
Mixed Monolayers of Long Normal Chain Fatty Acids with Long Normal Chain Fatty Alcohols
Authors: Matuo Hirosi , Hiromoto Kimio , Motomura Kinsi , Matuura Ryohei 
Published: July 2006

Abstract
The mixed monolayers of long normal chain fatty acids with long normal chain fatty alcohols were studied at various compositions and temperatures. The π-A curves of these systems were measured and the two-dimensional phase diagrams were obtained. The partial molar enthalpy change from the expanded to the condensed state was calculated. It was observed that the phase diagram and enthalpy change of these systems are similar to those previously obtained from the mixed monolayers of long normal chain fatty acids. The miscibility of these systems changes with the increase in the difference of the chain length, as in the systems of fatty acids. It was concluded that the monolayer behavior of the mixed system of an acid and an alcohol is analogous to that of the mixed system of the acid and an acid which contains one more carbon atom in a molecule than the corresponding alcohol.
The Spatial Distribution of Secondary Electrons Produced in the γ-Radiolysis of Water
Authors: Kowari Ken-ichi , Sato Shin 
Published: July 2006

Abstract
The spatial distribution of secondary electrons produced in the γ-radiolysis of water in the liquid phase has been theoretically calculated. The method consists of the combination of the procedure previously developed for the calculation of the G-value of electrons with the theory proposed by Fr\ddotohlich and Platzman for the slowing down of electrons in polar liquids. The G-value of the ion-pairs initially produced was calculated to be 6.8 on the assumption that the binding energies of electrons in water are equal to those in solid water at 77K. 27% of the ion-pairs were generated in isolated spurs. Another 27% of the ion-pairs were generated in condensed spurs, each of which contains more than one hundred ion-pairs. The other ion-pairs formed less condensed spurs, each of which contains from 2 to 100 ion-pairs. A new definition was given for the classification of spurs: isolated spurs, blobs, and short tracks; the original proposal was by Mozumder and Magee. The diameter of the isolated spur was estimated to be about 100 Å. The distribution of the distance between the parent positive ion and the thermalized electron in the isolated spur was well expressed by the function proposed by Abell and Funabashi, except at very short distances.
X-Ray Fluorescence Spectroscopy of Metal Sulfides
Authors: Maekawa Takashi , Kikuchi Niro , Fukuda Noriyuki , Yokokawa Toshio 
Published: July 2006

Abstract
The S Kα spectra of the sulfur compounds were measured. The S Kα energies of metal sulfides were less than that of the pure sulfur in accordance with the theoretical prediction. The S Kα shift for CaS (−0.239 eV) is the largest among those of metal sulfides examined in this study. In the sulfur+selenium binary mixtures, the S Kα energy goes more negative than that of sulfur with increasing the selenium content. These results can be interpreted in terms of the electronegativity of the counter atoms.
Studies of the Hydrous Titanium Oxide Ion Exchanger. IV. The Effect of Radiation and Heat Treatment
Authors: Inoue Yasushi , Tsuji Masamichi 
Published: July 2006

Abstract
The effects of 60Co γ-ray irradiation and of heat treatment in air have been studied on the properties of the hydrous titanium oxide ion exchanger. The ion-exchange capacity of the sodium form did not change at all, while that of the hydrogen form decreased a little, by the exposure of 5.2×108 R. The color of the exchanger, initially white, turned yellow upon irradiation. This exchanger was stable against heat treatment up to around 80 °C; thereafter the exchange capacity gradually decreased with the temperature until 324 °C, where it was abruptly reduced to about a quarter of the initial value. The examination of the titration curves showed that the most acidic exchange site was weaker than less acidic sites against heat treatment. The structural formula of this hydrous titanium oxide ion exchanger has been suggested on the basis of the ion-exchange capacity, the thermal decomposition curves, and such auxiliary data as the X-ray diffraction and the infrared spectra.
The Template-directed Synthesis of Oligonucleotide. II. The Interactive Properties of Nucleic Acid Base-binding Poly(4-vinylpyridine) and Its Related Compound with Nucleotides
Authors: Shimidzu Takeo , Murakami Akira , Konishi Yoshiyuki , Minami Manabu 
Published: July 2006

Abstract
The interactive properties of positively charged polynucleotide analogs, such as nucleic acid base-binding poly(4-vinylpyridine)s and their derivatives, with nucleotides have been investigated. The interactions of the positively charged polynucleotide analogs such as N-alkylated poly(4-vinylpyridine)s with 9-(ω-chloroalkyl)adenine and of N-alkylated poly(4-vinylpyridine) with 1-(2-bromoethyl)thymine with nucleotides were attributed predominantly to a base-base stacking under reinforcement by the coulombic attractive force. The purinepurine base interaction was found to be stronger than the purine-pyrimidine and the pyrimidine-pyrimidine interactions. The interaction was reduced by an increase in the ionic strength. The higher the charge density of the nucleotide was, the stronger was the interaction observed. On the other hand, a cross-linked positively charged polynucleotide analog such as N-alkylated cross-linked poly(4-vinylpyridine) with 9-(2-chloroethyl)adenine showed considerable selective interaction with the complementary nucleotide, uridine-5′-phosphate (pU), in both aqueous and pyridine solutions.
Isomorphism in the High-temperature Forms of the Pyrene Complexes with Five Polynitro Aromatic Compounds
Authors: Inoue Nobuaki , Matsunaga Yoshio 
Published: July 2006

Abstract
Crystalline pyrene complexes with 2,4-dinitrofluorobenzene, 2,4-dinitrochlorobenzene, 2,4-dinitrotoluene, 2,4-dinitrophenol, and picryl chloride exhibit polymorphic transitions. Their temperatures and associated enthalpies are presented. The high-temperature forms show essentially identical X-ray diffraction patterns, losing the special natures of the substituents on the acceptor molecules. Isomorphism is supported by the formation of complete solid solutions demonstrated for combinations of these forms. The enthalpy and entropy of melting of the present complexes are characterized by rather small values, 4–6 kcal mol−1 and 12–14 cal deg−1 mol−1respectively, indicative of anomalously high thermal motion or disorder in the high-temperature forms. Marked changes in the spectral and electrical properties by the transitions are noted in some cases.
The Formation of Alkyl Acetate in the Reaction of Trialkylborane with Lead(IV) Acetate or Phenyliodoso Acetate
Authors: Masuda Yuzuru , Arase Akira 
Published: July 2006

Abstract
In the reaction of trialkylborane with lead(IV) acetate or phenyliodoso acetate in benzene, about two thirds of the alkyl groups of trialkylborane were converted to the corresponding alkyl acetate without any isomerization of the alkyl group. Lead(IV) acetate reacted preferentially with the secondary alkyl group, while phenyliodoso acetate reacted only with the primary alkyl group. In either reaction, one mole of oxidizing agent was consumed for the formation of one mole of alkyl acetate.
An ESR Study of N-Sulfonylaminyls
Authors: Miura Yozo , Nakamura Yuji , Kinoshita Masayoshi 
Published: July 2006

Abstract
N-(3,5-Di-t-butylphenyl)-N-sulfonylaminyls, 3,5-t-Bu2C6H3–N–SO2-R, were investigated by means of ESR spectroscopy. The aN values are 7.8 G, and the aH values due to the N-phenyl ring protons are 5.6 (o-H) and 7.6 G (p-H). However, no couplings due to the protons in R have been detected. From these results, it is concluded that the unpaired electron is located on the nitrogen atom and the N-phenyl ring, negligibly delocalized onto the sulfonyl group.
Application of Infrared ATR Spectroscopy to Liquid Crystals. II. Surface-induced Orientation of Nematic MBBA and Reorientation in Electric Fields
Authors: Hatta Aritada , Nohara Hideaki , Suëtaka Wataru 
Published: July 2006

Abstract
A polarized infrared ATR technique was used to demonstrate the orientation of a nematic liquid crystal, N-(p-methoxybenzylidene)-p-butylaniline (MBBA), due to the walls of the electrode and an externally applied DC electric field. Polarized ATR spectra were obtained as a function of the field strength on liquid films 15 (μm thick between a silicon ATR prism and a brass plate serving as electrodes. The observed infrared dichroism revealed the average orientation of molecules in boundary layers about 1 μm thick on the Si electrode surface. The ordering or packing of molecules before application of the field affects the response of molecules to the electric field in a striking manner. Molecular orientations on the Si electrode are discussed in some detail.
Pyrolysis of Tetrasulfur Tetraimide
Authors: Hamada Shuichi , Kudo Yoshiyuki 
Published: July 2006

Abstract
Tetrasulfur tetraimide was pyrolyzed into sulfur, tetrasulfur tetranitride, tetrasulfur dinitride, ammonia, and nitrogen even below its apparent melting point, 143 °C, under atmospheric pressure; a small amount of hepta-sulfur imide was also observable. The tetrasulfur dinitride and nitrogen were formed from subsequent reactions between products. The overall pyrolysis consisted of the primary decomposition and the following subsequent ones, as judged from the stoichiometric relationships among the pyrolytic products: 3S4(NH)4=4S+2S4N4+4NH3, S4N4=S4N2+N2 (in the presence of sulfur), and S4N2=4S+N2. Partial pressures of ammonia at the primary pyrolysis were estimated to be 8.5×10−2, 2.1×10−1, 5.2×10−1, and 1.4 Pa at 60, 70, 80, and 90 °C respectively.