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141.
Iyota H Abe K Ikeda N Motomura K Aratono M 《Journal of colloid and interface science》2008,322(1):287-293
Miscibility and interaction of decyldimethylphosphine oxide (DePO) with ammonium chloride (AC), hexylammonium chloride (HAC), and dodecylammonium chloride (DAC) in adsorbed films and micelles were studied by surface tension measurements. Phase diagrams were drawn for the mixed adsorption, mixed micelle formation, and equilibrium between adsorbed films and micelles. Nonideal mixing of DAC and DePO was characterized by a negative excess Gibbs free energy and positive excess area of adsorption and negative excess Gibbs free energy of micelle formation. It is concluded that the interaction between DAC and DePO in adsorbed films and micelles is larger than those between the same surfactants alone due to two factors: ion-dipole interactions between the head groups of DAC and DePO and alkyl-chain/alkyl-chain interactions. 相似文献
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143.
Low-pressure chemical vapor deposition of TaCN films by pyrolysis of ethylamido-tantalum 总被引:1,自引:0,他引:1
Yoshio Ohshita Atsushi Ogura Asako Hoshino Shigeki Hiiro Hideaki Machida 《Journal of Crystal Growth》2000,220(4):604-609
Thin films of Tantalum nitride (TaN) were deposited from tetra-ethylamido-tantalum (Ta (NEt2)4) by low-pressure chemical vapor deposition. Good-quality step coverage is achieved below 400°C, because the deposition rate is determined by the reaction rates on the surface. The film resistivity increases, however, as the substrate temperature decreases. In order to obtain the low resistivity of films deposited at lower temperatures, we have increased the amount of injected H2 gas during the deposition. The resistivity decreases by the increase in the H2 gas flow rate, and it is shown that a large amount of H2 gas injection during the deposition is an effective method for obtaining both low resistivity and high-quality step coverage. The residual carbon concentration in the film is measured to be >10%, on the other hand, the concentration of N less than 1%. The microstructural investigation using transmission electron microscopy (TEM) reveals that crystalline structure of the deposited film has an amorphous phase. 相似文献
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146.
T. Takiue M. Tomioka N. Ikeda A. Matsubara M. Aratono K. Motomura 《Colloid and polymer science》1996,274(5):470-474
The interfacial tension of the aqueous solution of sodium dodecyl sulfate (SDS) and sodium decyl sulfate (SDeS) mixture against hexane was measured as a function of the total molality and composition of the surfactant mixture at 298.15 K under atmospheric pressure. The compositions of adsorbed film and micelle were evaluated numerically by applying the thermodynamic relations to the experimental results. These results were shown in the form of the phase diagrams of adsorption and micelle formation and compared with those of the aqueous solution of sodium perfluorooctanoate (SPFO) and SDeS mixture. It was found that the diagrams of SDS and SDeS system have swollen cigar shapes and are quite different from those of SPFO and SDeS system which show non-ideal mixing both in the adsorbed film and micelle. This finding was attributed to the fact that the interaction between fluorocarbon and hydrocarbon chains is weaker than that between hydrocarbon chains. 相似文献
147.
Treatment of (NH4)[Au(D‐Hpen‐S)2](D‐H2pen = D‐penicillamine) with CoCl2·6H2O in an acetate buffer solution, followed by air oxidation, gave neutral AuICoIII and anionic AuI3CoIII2 polynuclear complexes, [Au3Co3(D‐pen‐N,O,S)6]([ 1 ]) and [Au3Co2(D‐pen‐N,S)6]3? ([ 2 ]3?), which were separated by anion‐exchange column chromatography. Complexes [ 1 ] and [ 2 ]3? each formed a single isomer, and their structures were determined by single‐crystal X‐ray crystallography. In [ 1 ], each of three [Au(D‐pen‐S)2]3?metalloligands coordinates to two CoIII ions in a bis‐tridentate‐N,O,S mode to form a cyclic AuI3CoIII3 hexanuclear structure, in which three [Co(D‐pen‐N,O,S)2]? octahedral units and six bridging S atoms adopt trans(O) geometrical and R chiral configurations, respectively. In [ 2 ]3?, each of three [Au(D‐pen‐S)2]3? metalloligands coordinates to two CoIII ions in a bis‐bidentate‐N,S mode to form a AuI3CoIII2 pentanuclear structure, in which two [Co(D‐pen‐N,S)3]3? units and six bridging S atoms adopt ∧ and R chiral configurations, respectively. 相似文献
148.
19-Norvitamin D analogs 3a and 3b were synthesized from 25-hydroxyvitamin D, obtained via a bioconversion method. The synthetic route features a highly regio- and stereoselective hydroboration reaction to afford 25-hydroxy-3,5-cyclopropyl-vitamin D derivatives 12 having olefin at the C1-10-position. 相似文献
149.
Dissipative particle dynamics (DPD) was applied to fluid flow in irregular geometries using non‐orthogonal transformation, where an irregular domain is transformed into a simple rectangular domain. Transformation for position and velocity was used to relate the physical and computational domains. This approach was described by simulating fluid flow inside a two‐dimensional convergent–divergent nozzle. The nozzle geometry is controlled by the contraction ratio (CR) in the middle of the channel. The range of Reynolds number and CR, in this paper, was Re = 10hbox??200 and CR = 0.8 and 0.6, respectively. The DPD results were validated against in‐house computational fluid dynamic (CFD) finite volume code based on the stream function vorticity approach. The results revealed an excellent agreement between DPD and CFD. The maximum deviation between the DPD and CFD results was within 2%. Local and average coefficients of friction was calculated and it compared well with the CFD results. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
150.
Simulated annealing calculations were performed on a Penrose lattice with the aim of clarifying the relation between the interaction connections and the magnetic orders in the phason space. Alternating signs were assumed in the magnetic interactions up to the second shortest distances between spins. Two different types of long-range antiferromagnetic orders were found for two cases with reversed sign of the interactions. The two types of order were most adequately interpreted as the orders of subdivisions in the occupation domain in the phason space. Reasonable interpretations of the mechanism of the subdivisions are given on the basis of the physical interactions projected to the phason space. 相似文献