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151.
152.
Photovoltaic and Electroluminescence Bifunctional Devices with Starburst Amine and Rare-Earth-Complexes
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We fabricate the organic photovoltaic (PV) devices, in which 4,4',4"-tris-(2-methylphenylphenylamino)triphenylamine (m-MTDATA) and rare earth (RE) (dibenzoylmethanato)a(bathohenanthroline) (RE(DBM)abath) (RE = Nd or Pr) are used as electron donor and acceptor, and investigate their PV properties. The PV diode fabricated in the optimum processing conditions shows the open-circuit voltage of 1.91 V, short-circuit current of 0.1 mA/cm^2, fill factor of 0.38, and the overall power conversion efficiency of 1.9% when it is irradiated under UV light (4 m W/cm^2). The photocurrent density exhibits an increase of 20% at least when a very thin LiF layer is inserted between the RE-complexes and the A1 cathode. A strong electroluminescence from the interface is also observed and the maximum luminance of a yellow emission resulted from the exciplex is 580 cd/m^2 at 17 V bias. 相似文献
153.
This study introduces a two-dimensional (2D) partial response maximum likelihood (PRML) method to reconstruct a degraded data page having 2D inter-symbol interference for holographic data storage. The proposed 2D PRML method consists of 2D partial response (PR) target, 2D equalizer using least mean square algorithm, and 2D soft output Viterbi algorithm (SOVA) having just two one-dimensional (1D) SOVAs in horizontal and vertical directions. To accurately organize a trellis diagram of the 1D SOVA in structural accordance with the 2D PR target, this study proposes the self-reference process for the extrinsic information in the 1D SOVA. Finally, simulation results show that the proposed method has bit error rate performance similar to that of modified 2D SOVA having four 1D SOVAs despite the relatively low computational complexity. Moreover, parallel processing is possible in the two 1D SOVAs through the self-reference process. 相似文献
154.
MARY E. NEUBERT DAVID G. ABDALLAH Jr. SANDRA S. KEAST JULIE M. KIM SOONNAM LEE RYAN M. STAYSHICH 《Liquid crystals》2013,40(6):711-731
New diphenyldiacetylenes of the type with A, B = H and/or F; m = 0, 1; n = 1–4; and X = C n H2n+1, F, CF3 or CN were synthesized and their mesomorphic properties determined by hot stage polarizing microscopy and DSC. When m = 0, all of these compounds showed only a nematic phase except when X = CF3 when both nematic and smectic A phases were seen. Both clearing and melting temperatures were higher than those reported for substitution with the corresponding alkyl chains but the much larger increase in clearing temperatures produced considerably wider nematic phases. Eutectic mixtures of a few of these olefins yielded nematic materials also having much wider temperature ranges and higher clearing temperatures than the eutectic mixtures of the alkyl compounds, while retaining their high birefringence and low viscosities. Such materials are of interest for beam-steering devices. Four of the diacetylenes with m = 1 (A, B = H) were also prepared (X = C6H13, F, n= 2, 3). When X was C6H13 (n=2), the nematic range was smaller in the 2- than in the 1-olefin but wider than in the alkyl series. When X=F, either no nematic phase or a monotropic one was observed, whereas the 1-olefins gave a much wider nematic phase. Both transition temperatures were lower than those for the corresponding 1-olefin and alkyl analogues. The compound with X=C6H13 and n=2 had a melting temperature below room temperature. 相似文献
155.
The applicability of ultraviolet-light emitting diodes(LEDs)as a light source for photocatalysis using granular activated charcoal (GAC)impregnated with transition metal-enhanced photocatalysts for the control of volatile organic compounds(VOCs)was investigated. Two target compounds(toluene and methyl mercaptan)were selected to evaluate the removal activities of the TiO2/GAC composites.The photocatalysts were prepared by a sol-gel method.Methyl trimethoxy silane was added as a precursor sol solution to bind... 相似文献
156.
Effect of In Composition on Two-Dimensional Electron Gas in Wurtzite AlGaN/InGaN Heterostructures
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The effect of In composition on two-dimensional electron gas in wurtzite AlGaN/InGaN heterostructures is theoretically investigated. The sheet carrier density is shown to increase nearly linearly with In mole fraction x, due to the increase in the polarization charge at the AlGaN/InGaN interface. The electron sheet density is enhanced with the doping in the AlGaN layer. The sheet carrier density is as high as 3.7×1013 cm^-2 at the donor density of 10×1018 cm^-3 for the HEMT structure with x=0.3. The contribution of additional donor density on the electron sheet density is nearly independent of the In mole fraction. 相似文献
157.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
158.