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91.
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
92.
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
93.
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
94.
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
95.
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
96.
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
97.
Sunatsuki Y Ohta H Kojima M Ikuta Y Goto Y Matsumoto N Iijima S Akashi H Kaizaki S Dahan F Tuchagues JP 《Inorganic chemistry》2004,43(14):4154-4171
The [Fe(II)(H(3)L)](BF(4))(2).3H(2)O (1) complex was synthesized, where H(3)L (tris[[2-[(imidazole-4-yl)methylidene]amino]ethyl]amine) is a tripodal ligand obtained by condensation of tris(2-aminoethyl)amine and 4-formylimidazole (fim) in a 1:3 molar ratio. Starting from 1, a series of complexes, [Fe(II)(H(1.5)L)](BF(4))(0.5) (2) (=[Fe(II)(H(3)L)][Fe(II)(L)]BF(4)), [Fe(H(1.5)L)]BF(4) (3) (=[Fe(II)(H(3)L)][Fe(III)(L)](BF(4))(2)), [Fe(III)(H(3)L)](BF(4))(3).fim.H(2)O (4), and [Fe(III)(L)].2.5H(2)O (5), has been synthesized and characterized. The single-crystal X-ray structure of each complex has been determined. The Fe(II) compound, 2, and a mixed valence Fe(II)-Fe(III) compound, 3, involve formally hemi-deprotonated ligands, H(1.5)L. The structure of 3 consists of a homochiral two-dimensional assembled sheet, arising from the intermolecular hydrogen bonds between [Fe(II)(H(3)L)](2+) and [Fe(III)(L)](0) (3). All but 5 exhibit spin crossover between low-spin (LS) and high-spin (HS) states. This is a rare case where both Fe(II) and Fe(III) complexes containing the same ligand exhibit spin-crossover behavior. Magnetic susceptibility and M?ssbauer studies showed that 3 has three accessible electronic states: LS Fe(II)-LS Fe(III), HS Fe(II)-LS Fe(III), and HS Fe(II)-HS Fe(III). Compounds 1-3 show the light-induced excited spin-state trapping effect at the Fe(II) sites upon irradiation with green light. The solution magnetic properties, electronic spectra, and electrochemical properties of 1, 4, and 5 were also studied. 相似文献
98.
Mathematical meaning of the Clar's “aromatic sextet” is clarified by analysing the topological dependency of the sextet polynomial. Generalised recursive method for obtaining the sextet polynomial of a polyhex graph is presented. It is shown that the concept of the “super sextet” is necessarily introduced, if one-to-one correspondence between the Kekulé and sextet patterns is assumed. Topological dependency of the maximum number of resonant sextets is clarified and discussed in relation to the aromaticity and stability of polycyclic benzenoid hydrocarbons. 相似文献
99.
Tomoko Kanazawa Haruo Hosoya Suehiro Iwata 《International journal of quantum chemistry》1979,15(2):243-257
The π-electronic structures of the ground state of linear and highly branched polyenes with up to 80 π-electrons are calculated with particular reference to the alternation of the bond orders. The MO methods adopted are HMO, PPP , variable-β, γ, and its improved version. The effect of the electron correlation through singly and doubly excited configurations is estimated with a second-order perturbation calculation. The calculated bond orders systematically vary with the degree of approximation used. Most of the bond order values can be grouped into either a single or double bond region. In certain series of highly branched polyenes the bond orders of double and single bonds at the root of branching, respectively, get smaller and larger as the size of the molecule increases and sometimes their difference gets diminishingly small. The origin of these abnormal bond orders is discussed in terms of the π-electron flow networks. 相似文献
100.
Yao Xin-Sheng Yutaka Ebizuka Hiroshi Noguchi Fumiyuki Kiuchi Haruo seto Ushio Sankawa 《Tetrahedron letters》1984,25(48):5541-5542
A new monoterpenylbenzoquinone named arnebifuranone (5) was isolated from arnebiaeuchroma (Royle) Johnst. and its structure was elucidated to be a 2,3-dimethoxy-1,4-benzoquinone having a monoterpene side chain containing a furan ring. The monoterpene moiety is bonded to the benzoquinone ring with its head carbon. 相似文献