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111.
Tada A Geng Y Nakamura M Wei Q Hashimoto K Tajima K 《Physical chemistry chemical physics : PCCP》2012,14(11):3713-3724
This feature article focuses on the relationship between the interfacial structures constructed by molecular self-organization and the properties of organic photovoltaic devices. The use of self-assembled monolayers (SAMs) is reviewed for metal and metal oxide/organic interfaces, while surface-segregated monolayers (SSMs) are introduced as a new method for the modification of organic/organic interfaces. Research up to now has clearly demonstrated the effectiveness of the control of energy levels and other properties at the interfaces to enhance photovoltaic performance. The possibility of more precise control of the interfacial structures is also discussed. 相似文献
112.
A. Saitoh 《Journal of Raman spectroscopy : JRS》2007,38(5):537-542
Raman scattering from BiI3 and SbI3 crystals has been studied at hydrostatic pressures up to 2 GPa. The wavenumbers monotonically increased with pressure for all modes in BiI3. Although both crystals belong to the same space group, the pressure coefficients of SbI3 were significantly different from those of BiI3. At pressure P0 = 0.92 ± 0.01 GPa, the pressure coefficients of all modes changed. Above P0, all modes in SbI3 had positive pressure coefficients as they have in BiI3. By comparing this unusual behavior of the Raman lines in SbI3 around P0 with the results in BiI3 and comparing the two lattice structures, we suggest that the type of bonding of SbI3 changes to become more ionic and hence more similar to the bonding of BiI3. This change in structure is supported by changes in the bandwidth of the self‐trapped exciton (STE) luminescence and the slope of the absorption edge photon energy versus pressure. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
113.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. 相似文献
114.
115.
Ca2+-doping effects were studied on the N-type ferrimagnet of NdVO3. The chemical pressures by Ca2+-doping induced lowering of ferrimagnetic transition temperature Tc and compensation temperature θc, resulting in the phase transition from N- to P-type ferrimagnetic phase. In the N-phase, spontaneous magnetization Msp becomes zero at finite temperature θc and in the P-phase, Msp is positive in whole temperature range. It was revealed that NdVO3 and Ca0.1Nd0.9VO3 located in the N-phase and Ca0.2Nd0.8VO3 in the P-phase. This N→P transition by the chemical pressure was discussed by the intra- and inter-sublattice exchange integrals estimated from the molecular field approximation. 相似文献
116.
117.
S. Hagimura T. Saitoh Y. Yagihara 《Annals of the Institute of Statistical Mathematics》1988,40(3):419-438
Cement plant process is full of internal noise sources and feedback loops. Therefore, statistical approach is required to understand its dynamic characteristics. Time series analysis has been applied to some important subprocesses of a cement plant process. These are the vertical mill process, calcining process and clinker cooling process. Based on the AR models of these, a set of optimum controllers have been designed by modern control theory. Successful results of application are reported in this paper. A method of determining optimal production level is also discussed. 相似文献
118.
Polyion complexes of three chitosans with poly(vinyl sulfate) (PVS) and dodecylbenzene sulfonate (DBS) were examined by a potentiometric study that was to separately measure the pH of sample solutions individually prepared. Apparent formation constants (Ki) of ion association between the protonated amines of chitosan and the sulfates of PVS or the sulfonates of DBS were determined. The effects of pH, coexistent salt concentration, and molecular weight on the values of Ki were investigated in order to reveal the properties of the complexation. The values of Ki for chitosan-PVS were quite larger than that for chitosan-DBS. The deducing effect of the coexistent salt was strong against chitosan-PVS, but was weak against chitosan-DBS. Thus, chitosan-PVS complexes possessed a strong electrostatic binding, and chitosan-DBS complexes included a hydrophobic interaction. For chitosan-PVS complexes the effect of the coexistent salt was weaker for a high molecular weight of chitosan than for a low molecular weight. 相似文献
119.
Nickel(II), copper(II) and zinc(II) ions are extracted from an aqueous solution into carbon tetrachloride as their diethyldithiocarbamate (DDC) chelates. The extract, after removal of the solvent, is treated with meso-tetraphenylporphine (TPP) in benzyl alcohol at 140°C for 60 min. Quantitative conversion of the DDC chelate to the TPP chelate is obtained over the range 0.25–4.5 μg of each metal by use of 3 μgmol of TPP. The reaction mixture is analysed by reversed-phase high-performance liquid chromatography with spectrophotometric detection at 412 nm. Simultaneous determination of Cu and Zn in NBS bovine liver is possible by this procedure. 相似文献
120.
Transmission loss of holey fiber is found to depend on its structure, and to be caused by Rayleigh scattering at glass surface. Under this loss dependence, most promising is optical wiring application, for which fiber designs to realize bend-insensitivity and single-modedness are presented. 相似文献