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71.
Saigusa D Shibuya M Jinno D Yamakoshi H Iwabuchi Y Yokosuka A Mimaki Y Naganuma A Ohizumi Y Tomioka Y Yamakuni T 《Analytical and bioanalytical chemistry》2011,400(10):3635-3641
We recently demonstrated that nobiletin, a citrus flavonoid, exhibits anti-dementia action in animals. However, no determination methods for the content of nobiletin with beneficial action in the brain of nobiletin-administered animals have been developed, nor has its pharmacokinetics been revealed completely. Here, we established the high-performance liquid chromatography/photodiode array detection method for nobiletin determination using Bond Elut C18 SPE cartridges for extraction, where the calibration curve was linear over 0.025-10 ng, with coefficient of variation of less than 6.76%. This method enabled us to determine pharmacokinetic parameters of nobiletin given intraperitoneally or per os in the brain of mice. 相似文献
72.
Hayashi M Sasano Y Nagasawa S Shibuya M Iwabuchi Y 《Chemical & pharmaceutical bulletin》2011,59(12):1570-1573
A highly active organocatalyst for alcohol oxidation has been developed. 9-Azanoradamantane N-oxyl (Nor-AZADO 4), constituting an unhindered, stable nitroxyl radical, exhibits superior catalytic activity to 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and AZADOs in the oxidation of alcohols to their corresponding carbonyl compounds. 相似文献
73.
Okada T Yamanaka K Hirose Y Goto Y Tani T Inagaki S 《Physical chemistry chemical physics : PCCP》2011,13(17):7961-7967
The excited state characteristics of phenylene (Ph)-bridged periodic mesoporous organosilica (PMO) powders with crystal-like and amorphous wall structures are investigated. Crystal-like Ph-PMO has a molecular ordering of the bridging organic moieties with intervals of 0.76 and 0.44 nm parallel and perpendicular to the mesochannel direction, respectively, whereas amorphous Ph-PMO has no molecular-level periodicity in the wall. Fluorescence from the exciton and excimer of the Ph moieties and the defect center in the silicate network were detected at room temperature, but fluorescence from the excimer and the defect center were not detected at 77 K for crystal-like Ph-PMO dispersed in a methanol/ethanol mixed solvent. The decay curve of the exciton fluorescence of crystal-like Ph-PMO at room temperature was analyzed successfully using a one-dimensional diffusion model quenched by the defect center and the excimer site. The results were discussed in comparison with those for the crystal-like biphenylene-bridged PMO reported in the preceding paper (Yamanaka et al., Phys. Chem. Chem. Phys., 2010, 12, 11688-11696). The existence of excited states with various conformations including ground state dimers or aggregates of the Ph moieties was suggested for amorphous Ph-PMO. It was clearly apparent that the differences in the excited state dynamics reflected the differences in the molecular-level structure in the wall. 相似文献
74.
Yokoi T Sakuma J Maeda K Domen K Tatsumi T Kondo JN 《Physical chemistry chemical physics : PCCP》2011,13(7):2563-2570
The confined space synthesis method has been applied to the preparation of sodium tantalate (NaTaO(3)); hydrothermal reaction of NaOH and Ta(2)O(5) was carried out in the pores of a three-dimensional mesoporous carbon, which was replicated by the colloidal array of silica nanospheres (SNSs) 20 nm in size. This approach led to the formation of a colloidal array of NaTaO(3) nanoparticles 20 nm in size with a surface area of 34 m(2) g(-1). The photocatalytic performance of the colloidal array of NaTaO(3) nanoparticles for overall water splitting under UV irradiation (λ > 200 nm) was evaluated after loading a NiO cocatalyst onto NaTaO(3) samples. The NiO-loaded NaTaO(3) nanoparticles showed photocatalytic activity for overall water splitting more than three times as high as non-structured bulk NaTaO(3) particles. 相似文献
75.
The X-ray diffraction measurement for superionic conducting glass 5Agl–3Ag2O–2V2O5 was carried out at 12, 100, 200 and 290 K. The temperature dependence of structure factor S(Q) of 5Agl–3Ag2O–2V2O5 has been discussed based on the theoretical treatment that includes thermal vibration of atoms in noncrystalline materials. The effective overall Debye–Waller temperature parameter B increases with the increase of temperature. 相似文献
76.
Arai M. Sakuma T. Atake T. Kawaji H. 《Journal of Thermal Analysis and Calorimetry》2002,69(3):905-908
The phase transition and the crystal structures of CuITe were investigated by differential thermal analysis and X-ray powder
diffraction measurements in the temperature range between 300 and 683 K. The new phase transition in CuITe was observed at
592 K. The enthalpy of transition is ΔH=0.125 kJ mol-1. The new phase above 592 K belongs to tetragonal system with the space group I41
/amd.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
77.
Structures of 10AgI-3Ag2O-2V2O5, 3AgI-3Ag2O---2V2O5 and 2AgI---2Ag2O-V2O5 glasses have been investigated by neutron diffraction experiments. The characteristic features of observed structure factors S(Q) in 10AgI-3Ag2O-2V2O5 glass is similar to those of other superionic conducting glasses and molten AgI. From the standpoint of the pair distribution functions, it is clarified that the Ag-I and I-I correlation strength and Ag---Ag correlation length increase with increasing AgI concentration. Observed results suggest that the local AgI structure accompanied by the re-arrangement of silver ions is formed with highly doped iodide ions. 相似文献
78.
79.
The cation distribution in the superionic conductor α-AgI has been re-examined using neutron as well as X-ray diffraction data. A least squares analysis shows that the experimental data are very well explained by a structure model in which two silver ions are distributed over 12(d) sites of the space group Im3m with large asymmetric anharmonic thermal vibrations. 相似文献
80.