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901.
In this paper, photovoltaic characteristics of ITO/PEDOT:PSS/SubPc:Rubrene (mixed ratio R by weight)/C60/Bphen/Ag organic solar cells (OSCs) are analyzed in detail. The intrinsic properties of a SubPc:rubrene doped layer on device performance were discussed based on theoretical analysis of the experimental OSCs. The ratio R was 0, 0.25, 0.5, and 0.75,1, respectively. The results showed that when R was 0.75 performing the best, which owned the highest short circuit current (J sc ) 6.61 mA/cm2 and highest power conversion efficiency (PCE) 2.44%, the FF was 41% and the open circuit current (V oc ) was 0.905 V. The suitable HOMO level, absorption capacity, carrier transport ability and exciton diffusion length (L D ) of organic material are very important for the performance of the device. 相似文献
902.
903.
904.
The significant modifications to our recently constructed electron momentum spectrometer have been implemented. Compared with our previous report, the energy and the angle resolutions are significantly improved and reach △E = 0.45 eV, △θ = ±0.53° and △φ = ±0.84°, respectively. Moreover, the details of data reduction and the relation between azimuthal angle range and the sensitivity are discussed. 相似文献
905.
Ting LUO Yi ZHANG Xing-guo LI Li LIN Yue-yang ZHANG Qing-rong FENG 《Frontiers of Physics in China》2008,3(1):55-60
Systematic studies of synthesizing behaviors of sol-gel YBa2Cu3O7−x
samples in flowing oxygen atmosphere and their superconductivity have been performed. A set of high temperature ρ-T curves has been obtained for the whole synthesizing process. After four rounds of synthesizing, the resistivity of the sample
was around ρ=1.00×10−3Ω · cm at room temperature. The ρ-T curve of the fourth round shows that the orthorhombic to tetragonal phase transformation of the sample occurs around 600
°C, which is lower than that of the YBa2Cu3O7−x
sample prepared by conventional solid-state reaction method. Other measurements, such as X-ray diffraction, SEM measurement
and low temperature R-T and M-T measurement, were also performed. And the R-T and M-T measurement results suggest that during the synthesizing process, there exist some state at which the sample has better superconductivity
than the other states. Moreover, we found screw dislocations presenting on the sample broken surface from the SEM images.
This will change the concept that the screw dislocations can only grow on the surface of the YBCO thin films and single crystals.
相似文献
906.
Multiferroic NiFe2O4 (NFO)-BaTiO3 (BTO) bilayered thin films are epitaxially grown on (001) Nb-doped SrTiO3 (STO) substrates by pulsed-laser deposition (PLD). Different growth sequences of NFO and BTO on the substrate yield two kinds of epitaxial heterostructures with (001)-orientation, i.e. (001)-NFO/(001)-BTO/substrate and (001)- BTO/(001)-NFO/substrate. Microstructure studies from x-ray diffraction (XRD) and electron microscopies show differences between these two heterostructures, which result in different multiferroic behaviours. The heterostructured composite films exhibit good coexistence of both ferroelectric and ferromagnetic properties, in particular, obvious magnetoelectric (ME) effect on coupling response. 相似文献
907.
论中国海洋砂矿床类型 总被引:1,自引:0,他引:1
阮汀 《宁波大学学报(理工版)》1988,(2)
本文总结了作者二十多年砂矿工作的经验,搜集了国内近三百处海洋砂矿床(点)五十余种矿床类型划分的资料,比照国外同类型矿床,结合我国矿床特征,提出了新的海洋砂矿分类原则,矿床工业类型、成因-形态类型、成矿时代类型和保存类型等的划分系统,以及今后的找矿方向。 相似文献
908.
Yuxiang Li Weibing Deng Chunhong Xie 《Proceedings of the American Mathematical Society》2002,130(12):3661-3670
The initial-boundary value problems are considered for the strongly coupled degenerate parabolic system
in the cylinder , where is bounded and are positive constants. We are concerned with the global existence and nonexistence of the positive solutions. Denote by the first Dirichlet eigenvalue for the Laplacian on . We prove that there exists a global solution iff .
in the cylinder , where is bounded and are positive constants. We are concerned with the global existence and nonexistence of the positive solutions. Denote by the first Dirichlet eigenvalue for the Laplacian on . We prove that there exists a global solution iff .
909.
Total syntheses of nine novel phospholipids were accomplished to facilitate the identification and biological testing of compounds that are generated upon oxidative cleavage of arachidonate and linoleate esters of 2-lysophosphatidylcholine, the two most abundant polyunsaturated phospholipids in low-density lipoprotein. An efficient general synthesis exploiting 2-lithiofuran as a 4-oxo-2-butenoyl carbanion equivalent provided phospholipids containing gamma-keto-alpha,beta-unsaturated carbonyl functional arrays. By exploiting facile cis-trans isomerizations, two commercially available cis alkenes, (2Z)-2-butene-1,4-diol and 2,5-dihydrofuran, could be employed as starting materials for preparing the Horner-Wadsworth-Emmons reagent 4-(diethoxyphosphoryl)-2E-butenal, a valuable building block for the synthesis of 2,4-dienals. The reagent was exploited in a total synthesis of 13-oxotridec-9E,11E-dienoic acid, confirming the identity of this product that is generated upon autoxidation of linoleic acid and by decomposition of 13-hydroperoxy-9,11-octadecadienoate (13-HPODE), especially in the presence of redox active transition metal ions, cytochrome p-450, or hydroperoxide lyase. 相似文献
910.