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1.
Theoretical and Computational Fluid Dynamics - The present study aims to simulate a collision of two droplets containing immiscible liquids by employing a three- dimensional incompressible smoothed...  相似文献   
2.
The photocatalytic reactivities of chromium-containing mesoporous silica molecular sieves (Cr-HMS) under visible light irradiation have been investigated. Cr-HMS involves tetrahedral chromium oxide (Cr-oxide) moieties which are highly dispersed and incorporated in the framework of molecular sieve with two terminal Cr=O groups. In the presence of propane with molecular oxygen, a partial oxidation proceeded under visible light irradiation to produce acetone and acrolein, with high selectivity, while a complete oxidation proceeded under UV light irradiation mainly to produce CO2. The charge-transfer excited state of the tetrahedral Cr-oxide moieties plays a significant role in the photocatalytic reactions.  相似文献   
3.
α-Vinylfurans were obtained by phosphine-initiated cyclization of various enynes bearing a carbonyl group at the ene end in the presence of various aldehydes, in moderate to high yields. The reaction may consist of 1,6-addition of phosphine to the enynes, ring closure, and Wittig reaction between the ylid resulting from cyclization and an aldehyde. Thus, various aldehydes were able to be used in the reaction. The reaction was influenced greatly by the substituents at the acetylene position (R1) and the α-position of the carbonyl group (R3).  相似文献   
4.
A novel technique of measuring a magnetic Compton profile using the grazing angle geometry against a sample surface (Grazing Incidence Magnetic Compton Profile) has been successively developed. Measurements of a magnetic moment and a magnetic Compton profile are possible for a Fe 200 nm film on a thick glass substrate. The estimated thinnest limit for measurements is 100 nm for a Fe film.  相似文献   
5.
We construct the spaces that the elliptic Ruijsenaars operators act on. It is shown that they are extensible to nonnegative selfadjoint operators on a space of square integrable functions, or preserve a finite dimensional vector space of entire functions. These facts are shown in terms of the R-operators which satisfy the Yang–lBaxter equation. The elliptic Ruijsenaars operators are considered as the elliptic analogues of the Macdonald operators or the difference analogues of the Lamé operators.  相似文献   
6.
Reversible formation of F+-centers was observed over platinum promoted sulfated zirconia in the presence and absence of hydrogen. The intensity of ESR signal of F+-centers was increased by treatment in He stream and it was decreased rapidly by supply of hydrogen in gas phase. This behavior seems to be related to proton spillover.  相似文献   
7.
Bromobutide, a novel herbicide, was labeled with carbon-14 independently at the carbonyl group and the phenyl ring for use in metabolic studies. 14C-Carbonation of neopentylmagnesium chloride (3) gave 3,3-dimethyl[1-14C]butyric acid (4a) quantitatively. Chlorination of 4a with thionyl chloride followed by alpha-bromination with bromine yielded 2-bromo-3,3-dimethyl[1-14C]-butyryl halide (5a), which was subsequently condensed with alpha, alpha-dimethylbenzylamine (6a) to afford [carbonyl-14C]bromobutide (1a). The overall yield of 1a was 76% from barium [14C]-carbonate (2). Similarly, condensation of alpha, alpha-dimethyl[phenyl-14C]benzylamine (6b), which was prepared from alpha-methyl[phenyl-U-14C]styrene (7) in three steps, with 2-bromo-3,3-dimethylbutyryl halide (5b) gave [phenyl-14C]bromobutide (1b) in 67% yield after purification. The specific activities of 1a and 1b were 1.38 and 0.781 GBq/mmol (37.2 and 21.1 mCi/mmol), respectively.  相似文献   
8.
We propose a new analysis technique for characterizing molecular interactions that combines an energy decomposition scheme, such as the Kitaura-Morokuma decomposition method, with energy density analysis, which partitions the total energy of the system into atomic contributions. The combined scheme, termed Interaction-EDA, enables us to estimate the local contribution of interaction energy components, such as electrostatic, exchange, polarization, and charge transfer. The evaluation of the local interaction energy is rather important in large systems. For a numerical assessment, the Interaction-EDA method is applied to the process of CO adsorption on Si(100) - (2 x 1) surface.  相似文献   
9.
A method has been developed for highly sensitive determination of haloperidol in human serum involving a simple extraction procedure followed by gas chromatographic separation. Target components were separated from the extracting solvents with a Van den Berg type solventless sample injector before introduction Into a DB-1 capillary separation column. A surface ionization detector (SID), which has highly selective sensitivity for Substituted amines, was employed for quantitation using bromperidol as an internal standard. Chloroform proved to be the best extracting solvent, yielding a quantitative detection limit of 5 ng/ml (S/N = 2). Comparison of the response to target compounds obtained by the SID, FTD (flame thermionic detector), and FID (flame ionization detector) showed the SID to be superior.  相似文献   
10.
A supersonic jet instrument for fluorescence spectrometry is described. It consists of a high-temperature free expansion nozzle for continuous sample introduction and a vacuum chamber equipped with a high-speed pumping system. Rotationally cooled spectra obtained with the supersonic jet are compared with gas-phase spectra measured at high temperature for perylene and benzo[a]pyrene molecules. Each component of the unresolved band structure in the high-temperature spectra was found to be composed of a rotational congestion of several vibrational bands. For a 1:1 mixture of perylene and benzo[a]pyrene, selective detection is possible by using supersonic jet spectrometry. The detection limit for perylene is 100 ng. The advantage of this technique over other low-temperature spectrometric methods based on Shpol'skii and matrix isolation effects are discussed.  相似文献   
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