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11.
Yamamoto Y Yamamoto A Furuta SY Horie M Kodama M Sato W Akiba KY Tsuzuki S Uchimaru T Hashizume D Iwasaki F 《Journal of the American Chemical Society》2005,127(42):14540-14541
The oxidized octaethyltetraphenylporphyrin (1, OETPP) and the corresponding newly prepared octaisobutyltetraphenylporphyrin (3, OisoBuTPP) could be isolated from the reaction of OETPPLi2 (or OisoBuTPPLi2) with SOCl2. The X-ray analysis and the characteristic UV-vis spectra of 1 and 3 revealed that these are the first examples of 16 pi nonaromatic porphyrins. 相似文献
12.
Susumu Takigawa Masanori Koshimizu Takio Noguchi Tsutomu Aida Seiichi Takami Tadafumi Adschiri Yutaka Fujimoto Akira Yoko Gimyeong Seong Takaaki Tomai Keisuke Asai 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(2):611-615
We synthesized liquid scintillators incorporating ZrO2 nanoparticles for application in neutrinoless double beta decay experiments. ZrO2 nanoparticles of less than 10 nm in size were synthesized with sub- and supercritical hydrothermal methods. The Zr concentrations in the liquid scintillators were determined to be up to 1.4 wt% with inductively coupled plasma analysis, and the liquid scintillators were transparent to scintillation. These results indicate that these methods are applicable for the preparation of liquid scintillators for neutrinoless double beta decay experiments. 相似文献
13.
Yozo Chatani Takao Ohno Tadafumi Yamauchi Yasuhiko Miyake 《Journal of Polymer Science.Polymer Physics》1973,11(2):369-388
One of the cyclic oligomers of formaldehyde, 1,3,5,7,9,11-hexoxecane, was found to undergo polymerization in the solid state to form polyoxymethylene both during and subsequent to x- or γ-irradiation. The polymer yield increases with polymerization temperature but decreases drastically near the melting point of the hexoxecane crystal. In order to clarify the specificity of the solid-state polymerization, the crystal structure of hexoxecane was first analyzed; hexoxecane forms a trigonal crystal with cell dimensions of a = b = 7.917 Å, c = 11.345 Å, space group R3 –C3i2, three molecules of 3 symmetry per unit cell. The polyoxymethylene as polymerized from a single crystal of hexoxecane is highly crystalline and the crystallites are definitely oriented with respect to the original crystal. There are three kinds of oriented trigonal polyoxymethylene: i.e., with the polymer chains oriented along the 〈100〉, 〈001〉, and 〈210〉 axes of the hexoxecane crystal. The relative yields of these crystallites depend upon the polymerization temperature. In addition to the ordinary trigonal polyoxymethylene, oriented orthorhombic polyoxymethylene was also found in the case of polymerization during treatment with x-rays. 相似文献
14.
Daisuke Yamaki Tadafumi Ohsaku Hidemi Nagao Kizashi Yamaguchi 《International journal of quantum chemistry》2004,96(1):10-16
The Hartree–Fock–Bogoliubov (HFB) method, dealing with Bogoliubov orbitals, which consist of particle and hole part, can provide states with pair correlations associated with Cooper pairs. The dimension of HFB Fock matrices can be reduced by restrictions of spin states of Bogoliubov orbitals similarly to ordinary Hartree–Fock (HF) equations such as restricted HF (RHF), unrestricted HF (UHF), and generalized HF (GHF). However, there are few studies of moderate restricted HFB equations such as UHF‐based HFB equations. In this article, formulation and calculations of restricted HFB equations are described. The solutions of general and restricted HFB equations are compared. Pair correlations taking account of restricted and general HFB equations are discussed. © 2003 Wiley Periodicals, Inc. Int J Quantum Chem, 2004 相似文献
15.
Ameneh Sahraneshin Seiichi Takami Kimitaka Minami Daisuke Hojo Toshihiko Arita Tadafumi Adschiri 《Progress in Crystal Growth and Characterization of Materials》2012,58(1):43-50
Organic-functionalized nanoscale yttrium aluminum garnet (YAG) particles were synthesized via a simple rapid supercritical hydrothermal method in the presence of oleylamine and oleic acid as organic surface modifiers. The presence of the organic molecules resulted in the various morphologies of the produced YAG particles, including cubic, spherical and chainlike structures. Because of their hydrophobic surface character, as-synthesized particles were dispersible in organic solvents. 相似文献
16.
Tsuzuki S Honda K Fujii A Uchimaru T Mikami M 《Physical chemistry chemical physics : PCCP》2008,10(19):2860-2865
Geometries and interaction energies for methane clusters with naphthalene and pyrene were studied. Estimated CCSD(T) interaction energies for the clusters at the basis set limit were -1.92 and -2.50 kcal mol(-1), respectively. Dispersion is mainly responsible for the attraction. Electrostatic interaction is very small. Although the benzene-methane cluster prefers a monodentate structure, in which a C-H bond of the methane points toward the benzene, the methane clusters with the polycyclic aromatic hydrocarbons do not prefer monodentate structures. In the benzene-methane cluster, the weak electrostatic interaction stabilizes the monodentate structure. On the other hand the dispersion interaction controls the orientation of methane in the naphthalene and pyrene clusters. The dispersion interactions in these clusters are significantly larger than those in the benzene-methane cluster. The methane prefers the orientation which is suitable for stabilization by dispersion. Hydrogen atoms of the methane locate above the centers of hexagonal rings of the polycyclic aromatic hydrocarbons in the stable structures. The structures have a small steric repulsion and this positions them only a short distance from the aromatic plane. The large dispersion contribution to the attraction shows that interactions between carbon atoms are mainly responsible for the attraction, and that hydrogen atoms are not important for the attraction. This shows that the interactions between the methane and polycyclic aromatic hydrocarbons are not pi-hydrogen bonds. 相似文献
17.
Bin Wen Seiichi Takami Yoshiyuki Kawazoe Tadafumi Adschiri 《Journal of Physics and Chemistry of Solids》2012,73(11):1264-1267
The mechanical stabilities of K4 carbon and K4-like NaC2 have been studied by performing first-principle calculations. Total energies as functions of isotropic deformations and volume-conserving tetragonal and trigonal deformations have been calculated. For K4 carbon, the total energy shows a minimum for isotropic and trigonal deformations, but exhibits maxima for tetragonal deformation. In contrast, the total energy of K4-like NaC2 shows a minimum under all three deformations. These results indicate that K4 carbon is not a metastable phase, but that K4-like NaC2 is a metastable phase. In addition, the heat of formation of K4-like NaC2 is discussed. 相似文献
18.
Tsuzuki S Honda K Uchimaru T Mikami M Fujii A 《The journal of physical chemistry. A》2006,110(33):10163-10168
The CCSD(T) level interaction energies of CH/pi complexes at the basis set limit were estimated. The estimated interaction energies of the benzene complexes with CH(4), CH(3)CH(3), CH(2)CH(2), CHCH, CH(3)NH(2), CH(3)OH, CH(3)OCH(3), CH(3)F, CH(3)Cl, CH(3)ClNH(2), CH(3)ClOH, CH(2)Cl(2), CH(2)FCl, CH(2)F(2), CHCl(3), and CH(3)F(3) are -1.45, -1.82, -2.06, -2.83, -1.94, -1.98, -2.06, -2.31, -2.99, -3.57, -3.71, -4.54, -3.88, -3.22, -5.64, and -4.18 kcal/mol, respectively. Dispersion is the major source of attraction, even if substituents are attached to the carbon atom of the C-H bond. The dispersion interaction between benzene and chlorine atoms, which is not the CH/pi interaction, is the cause of the very large interaction energy of the CHCl(3) complex. Activated CH/pi interaction (acetylene and substituted methanes with two or three electron-withdrawing groups) is not very weak. The nature of the activated CH/pi interaction may be similar to the hydrogen bond. On the other hand, the nature of other typical (nonactivated) CH/pi interactions is completely different from that of the hydrogen bond. The typical CH/pi interaction is significantly weaker than the hydrogen bond. Dispersion interaction is mainly responsible for the attraction in the CH/pi interaction, whereas electrostatic interaction is the major source of attraction in the hydrogen bond. The orientation dependence of the interaction energy of the typical CH/pi interaction energy is very small, whereas the hydrogen bond has strong directionality. The weak directionality suggests that the hydrogen atom of the interacting C-H bond is not essential for the attraction and that the typical CH/pi interaction does not play critical roles in determining the molecular orientation in molecular assemblies. 相似文献
19.
Intermolecular interaction energies of 12 orientations of C(3)F(8) dimers were calculated with electron correlation correction by the second-order M?ller-Plesset perturbation method. The antiparallel C(2h) dimer has the largest interaction energy (-1.45 kcal/mol). Electron correlation correction increases the attraction considerably. Electrostatic energy is not large. Dispersion is mainly responsible for the attraction. Orientation dependence of the interaction energy of the C(3)F(8) dimer is substantially smaller than that of the C(3)H(8) dimer. The calculated interaction energy of the C(3)F(8) dimer at the potential minimum is 78% of that of the C(3)H(8) dimer (-1.85 kcal/mol), whereas the interaction energies of the CF(4) and C(2)F(6) dimers are larger than those of the CH(4) and C(2)H(6) dimers. The intermolecular separation in the C(3)F(8) dimer at the potential minimum is substantially larger than that in the C(3)H(8) dimer. The larger intermolecular separation due to the steric repulsion between fluorine atoms is the cause of the smaller interaction energy of the C(3)F(8) dimer at the potential minimum. The calculated intermolecular interaction energy potentials of the C(3)F(8) dimers using an all atom model OPLS-AA (OPLS all atom model) force field and a united atom model force field were compared with the ab initio calculations. Although the two force fields well reproduces the experimental vapor and liquid properties of perfluoroalkenes, the comparison shows that the united atom model underestimates the potential depth and orientation dependence of the interaction energy. The potentials obtained by the OPLS-AA force field are close to those obtained by the ab initio calculations. 相似文献
20.
Kimitaka Minami Shiori Goto Mehrnoosh Atashfaraz Takanari Togashi Toshihiko Arita Daisuke Hojo Seiichi Takami Tadafumi Adschiri 《Research on Chemical Intermediates》2011,37(2-5):415-419
This paper reports, for the first time, the enhanced dissolution of cellulose in subcritical water by addition of a fatty acid. Simply adding oleic acid dramatically promoted the dissolution of cellulose. High-pressure in-situ observation showed that cellulose dissolved in high-temperature water at approximately 500 K, which is 70 K lower than without oleic acid. The yield of oligo and monosaccharides with oleic acid at 473 K was seven times higher than without oleic acid. 相似文献