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321.
Junzo Nokami Mikio Kawada Rokuro Okawara Sigeru Torii Hideo Tanaka 《Tetrahedron letters》1979,20(12):1045-1046
α-Phenylthiocarboxylic acids were converted to the corresponding aldehydes or acetals with oxidative decarboxylation and desulfurization by electrolysis. 相似文献
322.
Hydration of ion pairs is an essential process in various physicochemical phenomena occurring in solutions. Isolated clusters of an ion pair solvated with finite number of waters have been considered as a model system for the critical evaluation of microscopic interactions involved in the process, and theoretical studies have contributed exclusively to the subject up to now. Here we report the first experimental characterization of structure and internal dynamics of hydrated ion pairs, NaCl-(H2O)n (n = 1-3). The measurements of their rotational spectra have proven that the clusters have cyclic forms, in which Na+ and Cl- ions are strongly interacted with the O and H atoms of the solvent molecules, respectively. The Na-Cl distance shows a pronounced increase with the successive addition of water molecules. The separation for n = 3 approaches the value predicted for the contact ion-pair state in aqueous solution by recent molecular dynamics simulations. 相似文献
323.
Junzo Hirano 《Tetrahedron》2006,62(43):10065-10071
4-Quinolone (4-QO) was evaluated as a simple and novel fluorescent anion sensor, and the modification of its emission color was carried out. The series of 4-QO derivatives having molecular orbitals with different energy levels was designed by substitutions at the 6 and 7 positions based on the molecular orbital calculations. All derivatives showed drastic fluorescence enhancements in the presence of F− via the intramolecular charge transfer mechanism, and the successful modification of the emission color was achieved. The anion-induced emission colors of these derivatives as well as their binding affinities for F− could be predicted by ab initio quantum chemical calculations, indicating that the present calculations are useful in designing new anion sensors. 相似文献
324.
Transformation among the aggregate forms of bacteriochlorophyll (BChl) c characterized by the wavelength of the Qy absorption, i.e. the dimer (B675), B705, B720 and B745, was traced by electronic-absorption spectroscopy for each of the isomers including R[E,E], R[P,E], R[I,E], S[P,E] and S[I,E] suspended in the mixtures of methylene chloride and n-hexane. A combination of NMR spectroscopy determining the structural motifs and calculation of the shift of the Qy absorption reflecting the long-range transition dipole-transition dipole interactions among the macrocycles in the entire aggregate structures proposed the following models: B705d (B705d'), a linear array of straight (inclined) columns consisting of a pair of the piggyback dimers; B720d and B745d, an assembly of two and five shifted-inclined columns consisting of more than six piggyback dimers; and B720m and B745m, an assembly of one and two parallel stepwise stacking of approximately 30 monomers. Calculations of the steric energies rationalized two different pathways of transformations: the dimer-->B705d (B705d')-->B720d-->B745d for the R isomers; and the monomer-->(B720m)-->B745m for the S isomers. Addition of S[I,E] seems to trigger the B745d-->B745m transformation of the R isomers. 相似文献
325.
Hiroko Satoa Hiroshi Tsuji Hitoshi Sasaki Shinichi Ikemura Yasuhito Gotoh Junzo Ishikawa Sei-ichi Nishimoto 《高分子科学》2004,(1):69-75
INTRODUCTIONA negative ion-implantation technique[1,2] developed by us for use in semiconductors, integrated circuits (IC),and large scale-integrations (LSI) has been studied in its application on biotechnology. The implantation of highion energy beams causes the impairment of insulators such as common synthetic polymers. Our negative ion-implantation, however, is considered to result in less charge-up problems compared with positive ion-implantation. That is, negative ionic species can… 相似文献
326.
327.
Hiroshi Mizoguchi N.S.P. Bhuvanesh M.A. Subramanian 《Journal of solid state chemistry》2011,184(6):1381-1386
The new compounds Ce2/3−xRh2O4 (x∼0.11-0.14) and CeRh2O5 have been prepared. Their structures were determined from single crystal X-ray diffraction data. Electrical and magnetic properties were also evaluated. Based on the structural analysis and physical properties, oxidation states for CeRh2O5 can be assigned as Ce4+Rh3+2O5. A small variation in x was detected for Ce2/3−xRh2O4 indicating a formula ranging from Ce3.64+0.55Rh3+2O4 to Ce3.81+0.525Rh3+2O4. 相似文献
328.
329.
A series of 1,1-dimethyl-4,5:8,9-dibenzo-1-silacycloundeca-4,8-diene-2,6,10-triyne (DST)-substituted phenyleneethynylenes were successfully synthesized by reaction of Me2SiCl2 with dimagnesium dianions which had been prepared from 2,2′-diethynyl(diphenylethyne) derivatives by treatment with 2 equiv of MeMgBr. All the products were white-to-pale yellow powder stable enough to handle in the air, and their photoluminescence spectra were recorded both in solution and in solid state. 相似文献
330.
Nobutoshi Arai Hiroshi Tsuji Masayuki Ohsaki Toyotsugu Ishibashi Junzo Ishikawa 《Applied Surface Science》2009,256(4):954-957
We have investigated cathodeluminescence (CL) of Ge implanted SiO2:Ge and GeO2:Ge films. The GeO2 films were grown by oxidation of Ge substrate at 550 °C for 3 h in O2 gas flow. The GeO2 films on Ge substrate and SiO2 films on Si substrate were implanted with Ge-negative ions. The implanted Ge atom concentrations in the films were ranging from 0.1 to 6.0 at%. To produce Ge nanoparticles the SiO2:Ge films were thermally annealed at various temperatures of 600-900 °C for 1 h in N2 gas flow. An XPS analysis has shown that the implanted Ge atoms were partly oxidized. CL was observed at wavelengths around 400 nm from the GeO2 films before and after Ge−-implantation as well as from SiO2:Ge films. After Ge−-implantation of about 0.5 at% the CL intensity has increased by about four times. However, the CL intensity from the GeO2:Ge films was several orders of magnitude smaller than the intensity from the 800 °C-annealed SiO2:Ge films with 0.5 at% of Ge atomic concentration. These results suggested that the luminescence was generated due to oxidation of Ge nanoparticles in the SiO2:Ge films. 相似文献