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81.
Yabuuchi N Yamakawa Y Yoshii K Komaba S 《Dalton transactions (Cambridge, England : 2003)》2011,40(9):1846-1848
A nearly single-phase of a low-temperature (LT) phase of Li(2)FeSiO(4) is prepared by a hydrothermal method at 150 °C. We report the detailed crystal structure of LT-Li(2)FeSiO(4) (S.G. Pmn2(1)) by applying Rietveld/MEM analysis to the synchrotron XRD pattern. LT-Li(2)FeSiO(4) shows 150 mA h g(-1) as the positive electrode materials of rechargeable batteries. 相似文献
82.
Synthesis of thermosensitive polymer/mesoporous silica composite and its temperature dependence of anion exchange property 总被引:1,自引:0,他引:1
Murakami K Yu X Watanabe S Kato T Inoue Y Sugawara K 《Journal of colloid and interface science》2011,354(2):771-776
An anion exchanger consisting of amino-functionalized MCM-41 type mesoporous silica coated with temperature-responsive polymer, poly(N-isopropylacrylamide) (PNIPAM), was synthesized in this study. The structure of this composite was characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and elemental analysis. The XRD pattern showed that the synthesized composite had the ordered hexagonal structure and the interplanar spacing, d(100), was around 40?. The amount of surface-grafted thermosensitive polymer was estimated to be about 0.8wt.% by elemental analysis. The adsorption-desorption behavior of methyl orange in this synthesized material depended on the temperature of aqueous solution: at 25°C, the reversible adsorption-desorption of methyl orange was repeated with changing pH of the solution; at 40°C, the methyl orange was not adsorbed and desorbed independent of pH of the solution. 相似文献
83.
Omata T Takahashi K Hashimoto S Maeda Y Nose K Otsuka-Yao-Matsuo S Kanaori K 《Journal of colloid and interface science》2011,355(2):274-281
A novel synthesis route to organic-capped and colloidal ZnO quantum dots (QDs) has been developed. Specifically, zinc-di-t-butoxide and zinc-di-n-butoxide are hydrolyzed by very dilute water (400-600 mass ppm) in hydrophilic benzylamine and polymerized to ZnO by dehydration and/or a butanol elimination reaction. Growth of the ZnO QDs and exchange of the surface capping ligand from the hydroxyl groups and/or benzylamine to the oleylamine occur by heating the colloidal solution after addition of the oleylamine at 100-180°C. The final ZnO QDs with diameters in the range of 3-7 nm are highly dispersible in various organic solvents. The ZnO QDs exhibit the quantum size effect upon UV emission; it was controlled between 3.39 and 3.54 eV in the present study. The defect-related Vis emission decreased and the UV emission becomes dominant when zinc-di-n-butoxide with a 99.99% zinc purity is used as the starting material. The intensity of the photoluminescence UV emission is 1.5 times higher than that of the Vis emission. 相似文献
84.
Machiguchi T Hasegawa T Saitoh H Yamabe S Yamazaki S 《The Journal of organic chemistry》2011,76(13):5457-5460
Through variable-temperature solution-state NMR and molten- and solid-state CP/MAS (13)C NMR spectra, thiotropolone is found to exist as two rapidly equilibrated tautomeric structures, thione and enethiol, even in the solid state far below the melting point. The crystal structure shows an almost perpendicular packing, suggesting that the intramolecular hydrogen bond is dominant. 相似文献
85.
Paths of the Kolbe?CSchmitt reaction were investigated by the use of RB3LYP/6-311(+)G(d,p) density functional theory calculations. In a monomer model composed of C6H5O?, Na+ and CO2 affording sodium salicylate [C6H4(OH)CO2 ?Na+], a proton-shift step (Z Naturforsch 57a:812, 2002) was found to have an unrealistically large activation energy. In consideration of the phenol volatilization in the Kolbe??s experiment and the need of the linearity of the proton-transfer path, a dimer model was constructed. Again, a mutual proton-transfer step has a large activation energy. Alternatively, in a dimer model, a transfer path where the phenoxide ion in one monomer acts as a proton acceptor was found to have a reasonable energy. Addition of one more sodium ion leads to the significant lowering of activation energies. Thus, in the dimer, two monomers behave differently (A?+?A????A?+?B); one is as if it were a catalyst. 相似文献
86.
Shinichi Suzuki Yasuhiro Suzuki Hikoto Ohta Masaaki Kasamatsu Toshio Nakanishi 《Analytical sciences》2005,21(7):775-778
Thirteen arsenous acid samples of known origins and refining methods were collected. Each sample was subjected to quantitative analysis of any impurity elements present using synchrotron radiation X-ray fluorescence spectrometry (SR-XRF) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). The trace elements selected were Sn, Sb and Bi for the reasons that they were considered not to be changed by their circumstances and that they showed high sensitivity to SR-XRF. These results obtained by both methods were compared and the correlation between these two methods was determined. The quantification of trace impurities obtained by SR-XRF using As as an internal standard showed good agreement with the results obtained by ICP-AES. The discrimination of refining method became possible by the comparison of these impurities' contents measured with non-destructive SR-XRF using several arsenous acid particles. 相似文献
87.
Shinichi Kimura Kunihiro Osaki Michio Kurata 《Journal of Polymer Science.Polymer Physics》1981,19(1):151-163
The rheological behavior of an uncrosslinked polybutadiene on sudden application of finite strain was examined. The shear stress σ, two components of birefringence, and the extinction angle were measured in shear (magnitude of shear γ ≤ 3.5) and tensile stress and the birefringence were measured in uniaxial elongation (elongation ratio λ ≤ 3.8). Measurements were performed at 30°C with a tensile tester equipped with appropriate sample holders. The stress-optical coefficient was 3.01 × 10?9Pa?1. The first and second normal-stress differences v1 and v2 were separately evaluated with the use of stress-optical law. The Lodge—Meissner relation v1 = γσ held good. The ratio v2/v1 was independent of time and varied from about ?0.3 to ?0.2 with increasing γ in the range of measurements. Each of the stress components was factored into a function of strain and one of time, and the latter was common to all the stress components. Simple formulas were proposed to represent stress components in step deformations. 相似文献
88.
The construction of the linearized four-dimensional multisupergravity from five-dimensional linearized supergravity with discretized fifth dimension is presented. The one-loop vacuum energy is evaluated when (anti)periodic boundary conditions are chosen for (bosons) fermions, respectively, or vice versa. It is proposed that the relation between discretized M-theory and strings may be found in the same fashion. 相似文献
89.
90.
Shinichi Ueji Kazumi Nakatsu Hiroshi Yoshioka Kenji Kinoshita 《Tetrahedron letters》1982,23(11):1173-1176
The crystals of the title compound contain both intra- and inter-molecular OH?π hydrogen bonds (the first example of bifurcated OH?π bonds), the stereochemistry of which has been elucidated by an X-ray structure analysis; this bifurcated bond is also supported by the observation based on the IR spectrum of the crystals. 相似文献