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1.
Hyperfine interaction constants (HFICs) of dangling bonds for CN and SiN films were calculated by density-functional theory. The averaged 14N isotropic HFICs for C dangling bonds are almost equal to those for Si dangling bonds. The anisotropic 14N HFICs calculated for C dangling bonds are larger than those for Si dangling bonds by a factor 2. The calculated results were compared with experimental results obtained by electron spin resonance and electron nuclear double resonance. It was indicated that the carbon dangling bonds are located such that they avoid N atoms in CN films. 相似文献
2.
Photochemical deprotection of nitro-substituted benzenesulfenates via photoinduced electron transfer
Kan Wakamatsu Mitsuru Kouda Kazuyoshi Shimaoka Haruo Yamada 《Tetrahedron letters》2004,45(34):6395-6398
The photochemical deprotection of alkyl 2,4-dinitrobenzenesulfenate or alkyl 2-nitrobenzenesulfenate was successfully achieved by addition of triethylamine, while it was unsuccessful without triethylamine. The sulfur-oxygen bond cleavage is thought to occur heterolytically in the sulfenate anion radical produced by photoinduced electron transfer with triethylamine. 相似文献
3.
Haruo Sato 《Hyperfine Interactions》1990,57(1-4):2089-2094
Mössbauer spectra of ferrocene adsorbed on silica gel were measured in order to study the state of adsorption. Ferrocene adsorbed on silica gel tended to oxidize in air and form ferricenium ion. It is assumed that the oxidation of adsorbed ferrocene was caused by surface hydroxyls on the silica gel and O2 in air. It was observed that ferrocene adsorbed weakly at 293 K, although the ferricenium ion adsorbed strongly at 293 K. Thus the adsorption states of ferrocene depend on the experimental condition. 相似文献
4.
Tomonari Wakabayashi Daisuke Kasuya Haruo Shiromaru Shinzo Suzuki Koichi Kikuchi Yohji Achiba 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1997,40(1):414-417
Systematic fractional change in the yield of various isomers of fullerenes was revealed to strongly depend on temperature of a buffer gas. A new kinetic consideration is proposed for understanding the observed temperature- and pressure-dependence of yield of fullerenes. The model consists of three competitive reactions in consideration of plausible behaviors of a precursor, (1) decomposition into smaller fragments, (2) isomerization leading to formation of a stable fullerene cage, and (3) growth into a larger carbon cluster. Arrhenius activation energy of formation of stable fullerenes was determined to be 0.8 eV for both C60 and C70, while a higher energy of 2.0?3.3 eV for seven different isomers of higher fullerenes ranging from C76 to C84. Correlation in the activation energy is noted for a series of higher fullerenes with different sizes, suggesting the existence of a specific precursor in their formation processes. 相似文献
5.
Sulfate ion in river water is determined by flow injection analysis at a rate of 30 samples per hour; the sulfate contents are typically less than 30 ppm. The reagent solution contains dimethylsulfonazo-III, barium chloride, potassium nitrate and chloroacetate buffer in 70% () ethanol, and is saturated with barium sulfate. The aqueous carrier stream is also saturated with barium sulfate. The sample is filtered and treated with Amberlite IR120-B cation-exchanger before injection into the carrier stream, and the decoloration of the barium—dimethylsulfonazo-III complex by sulfate is measured at 662 nm. The calibration graph is linear over the range 0–30 μg ml-1 for sulfate in water. 相似文献
6.
Air containing particulate material was passed continuously for one month through a low-volume air sampler equipped with a cyclone to exclude particulates greater than 10 μm in diameter. The samples and filters were ashed in a low-temperature plasma and, after addition of In2O3 support, palladium internal standard and graphite buffer, the ashes were analyzed by a.c. are emission spectrometry. Standard samples were prepared from a commercial standard containing 49 elements. The procedure allows the determination of 14 trace metals (Ag, Al, Cr, Cu, Fe, Ga, Mn, Mo, Ni, Pb, Sn, Ti, V, Zn) with relative standard deviations of 1.4–15.1%. The procedure has been applied successfully to monthly determinations of the average atmospheric concentrations of these elements in Kobe City for the past three years. 相似文献
7.
Kiyotaka Shigehara Haruo Matsunaga Eishun Tsuchida 《Journal of polymer science. Part A, Polymer chemistry》1978,16(8):1853-1863
Some polymeric azine or thiazine dyes were prepared by radical polymerization of dye monomers or by polymer reactions between dyes and suitable prepolymers, and their photoredox reactivities were studied. The thionine polymers containing labile ? OH groups exhibited photochromism and thermochromism, which were extremely sensitive to the moisture content of the polymer film. The reversibility of the photochromism and thermochromism increased with the water content in the film. The water-soluble polymeric dyes were photobleached under the influence of suitable reducing agents. The degree of photobleaching was smaller than for the monomeric systems except for the dye polymers containing ? OH groups, probably because of the large steric hindrance of the polymers. 相似文献
8.
Motohiko Hikuma Haruo Obana Takeo Yasuda Isao Karube Shuichi Suzuki 《Analytica chimica acta》1980,116(1):61-67
The sensor consists of immobilized E. coli (which contains glutamate decarboxylase) and a carbon dioxide gas-sensor. Continuous introduction of sample solution into a flow system incorporating the sensor gives a potential which increases until a steady state is reached after 5 min. Measurements can also be made with only a 1- or 3-min introduction period with little loss of sensitivity. Calibration plots of mV measurements vs. logarithmic glutamic acid concentration are linear in the range 100–800 mg l-1. The sensor is highly selective, stable and reproducible. It has been applied to the determination of glutamic acid in fermentation broths. 相似文献
9.
The number of perfect rnatchings for the linear 2 × 2 ×n cubic lattice was analytically derived by diagonalizing the skew—symmetric 4n × 4n determinant, whose non—zero off—diagonal elements are either ±1 or ±i (pure imaginary number). The basic formulation invoking the matrix manipulation follows that of Kasteleyn, but the result obtained in this paper is the first example of the analytical solution for a special case of the three-dimensional Ising model.received by the Publisher 20 September 1989 相似文献
10.