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131.
132.
The performance test of a shell-and-plate type evaporator (total surface area 21.95 m2, length 1450 mm, width 235 mm, 100 plates) for ocean thermal energy conversion (OTEC) plants is reported. Freon 22 (R22) and ammonia (NH3) were used as the working fluid. Empirical correlations are proposed for predicting the boiling heat transfer and the heat transfer coefficients on the water side. The water-side pressure drop is about 2.9 × 104 N/m2 when the warm water velocity is 0.7 m/s. The water-side friction factor is obtained. 相似文献
133.
Diamond powders with silicon additives were shock compressed by using a flyer impact technique. Pressure and temperature histories in the powder mixtures were numerically simulated in order to determine the optimum experimental condition which resulted in the highest Vicker's hardness. This was found to be: an initial diamond particle size of 2–4m at 7.2 % silicon by volume. The results of the simulations were consistent with the distribution of the microstructure and the microhardness in the compact.This article was processed using Springer-Verlag TEX Shock Waves macro package 1990. 相似文献
134.
In order to prepare high-quality CuInS2 thin films vapor phase decomposition patterns of three copper-indium binuclear complexes, and as candidates for source materials were investigated using EI MS. The complex 1c showed series of intensive peaks due to the fragmentation of M+. For 1a, only a fragmentation pattern starting from BuIn(S2CNBu2)2 was detectable. This should suggest that 1a decomposed into BuIn(S2CNBu2)2 and copper sulfide before vaporization. In addition an ambiguous feature could be observed for 1b, viz. two fragmentation paths. Consequently, we judge that 1c is a suitable source complex to prepare CuInS2 thin films via a single-source OMCVD process. Thus chalcopyrite CuIns2 thin films were successfully prepared via single-source OMCVD using 1c as a source complex, with Tsubstrate400°C, Tsource80°C, base pressure 0.7 Torr and carrier (nitrogen) flow rate 0.8 L min?1. Fragmentation of two copper dithiocarbmates, Cu(S2CNBu2)2 and Cu[S2CN(i-Pr)2]2, and two butylindium thiolates, Bu2InS(i-Pr) and BuIn[S(i-Pr)]2, as components of 1 is additionally discussed. 相似文献
135.
136.
Masaaki Abe Haruo Akashi Kiyoshi Isobe Akihiko Nakanishi Atsushi Yagasaki 《Journal of Cluster Science》1996,7(1):103-107
The methallyl moieties of [{(3-C4H7)2Rh}2(V4O12)]2– couple to yield 2,5-dimethyl-1,5-hexadiene in a selective manner by the action of P(OEt),3, while the reaction of [(
3-C4H7)2 Rh(acac)] with P(OEt)3 produces a mixture of organic compounds. The result shows that the vanadate support has a significant influence on the reactivity of organometallic complexes. 相似文献
137.
YanCAI MingQingCHEN JuanXU PinFangWU AkashiMITSURU XiaoHuaHUAN 《中国化学快报》2004,15(9):1109-1112
Poly (N-vinylacetamide) (PNVA) was synthesized by the free radical polymerization and its samarium (Ⅲ) binary complex was prepared and characterized by means of IR, UV-vis, X-ray photoelectron spectroscopy (XPS) and fluorescence spectra. The fluorescent intensity of samarium (Ⅲ) characteristic emission was increased significantly due to efficient energy transfer from polymeric ligand to Sm (Ⅲ) ion in the complex. 相似文献
138.
Miharu Eguchi Hiroshi Tachibana Shinsuke Takagi Haruo Inoue 《Research on Chemical Intermediates》2007,33(1-2):191-200
The intercalation behavior of cationic porphyrin derivatives within the interlayer spaces of nano-layered clay minerals has been investigated. The porphyrins were successfully intercalated by the newly adopted method of repeated freeze-thaw cycles. The absorption spectra of the porphyrins were compared in the solution phase, adsorbed onto the exfoliated clay nano-sheets, intercalated within the interlayer spaces of clay sheets dispersed in water and intercalated in dry films. Substantial red shifts of the λmax values in the absorption spectra of the porphyrins were observed on the exfoliated clay sheets, and further red shifts were induced within the interlayer space. The dry films of the intercalated samples exhibited the largest red shifts. X-ray diffraction studies revealed that the clearance space between the layers in these intercalated hybrid compounds is only large enough for the porphyrins to be rigidly packed parallel to the clay layer. For the exfoliated clay nano-sheets, theoretical calculations were carried out on the correlation between the dihedral angle of the meso-substituted pyridiniumyl plane vs. the porphyrin ring and the λmax of the porphyrin Soret band. An extrapolation of the experimental λmax value to the correlation curve, afforded the dihedral angle to be 61.6°. The microscopic structure of the adsorbed state of the cationic porphyrins on the exfoliated clay nano-sheets was, thus, proposed to involve an orientation parallel to the clay surface, with a distance of 0.15 nm from the surface, which implies the expulsion of the solvent water molecules. 相似文献
139.
Polarized reflection spectra of a K-TCNQ single crystal have been measured at 27,295 and 413 K. The absorption spectra were derived from the observed reflection spectra by Kramers-Kronig transformation. At 27 K, the near-infrared absorption band which is associated with the charged transfer between TCNQ? ions, splits into a strong sharp peak at 8 × 103 cm?1 and a weak broad band at 11 × 103 cm?1. These bands were interpreted in terms of the strongly correlated extended Hubbard model including the nearest-neighbor Coulomb interaction. 相似文献
140.
A general expression of the perfect matching number for thel x m x n cubic lattice was conjectured and examined for infinitely large systems. The asymptotic value of the square of the perfect matching number was calculated by numerical integration. The present treatment will give a key to obtain the true analytic solution of the perfect matching numbers for the 3-dimensional lattices. 相似文献