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151.
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152.
Pentacene-based organic thin-film transistors 总被引:7,自引:0,他引:7
Yen-Yi Lin Gundlach D.I. Nelson S.F. Jackson T.N. 《Electron Devices, IEEE Transactions on》1997,44(8):1325-1331
Organic thin-film transistors using the fused-ring polycyclic aromatic hydrocarbon pentacene as the active electronic material have shown mobility as large as 0.7 cm2/V-s and on/off current ratio larger than 108; both values are comparable to hydrogenated amorphous silicon devices. On the other hand, these and most other organic TFT's have an undesirably large subthreshold slope. We show here that the large subthreshold slope typically observed is not an intrinsic property of the organic semiconducting material and that devices with subthreshold slope similar to amorphous silicon devices are possible 相似文献
153.
154.
Alain Estve Adeline Bail Georges Landa Ahmed Dkhissi Marie Brut Mehdi Djafari Rouhani Jan Sudor Anne-Marie Gu 《Chemical physics》2007,340(1-3):12-16
Possible collapsed forms of poly(N-isopropylacrylamide) molecules are reviewed on the basis of first principle calculations. Various configurations and associated conformations are detailed. The calculated optimized structures exhibit different possibilities of creating networks of intra-molecular bonds of the hydrogen type. We show that the most remarkable one is able to form a local, self-saturated and well ordered helix. We also indicate in which direction the synthesis of the molecule should be oriented to improve its global behavior in term of hydrophobic/hydrophilic behavior. 相似文献
155.
Finitely generated linear semigroups over a field K that have intermediate growth are considered. New classes of such semigroups are found and a conjecture on the equivalence of the subexponential growth of a finitely generated linear semigroup S and the nonexistence of free noncommutative subsemigroups in S, or equivalently the existence of a nontrivial identity satisfied in S, is stated. This ‘growth alternative’ conjecture is proved for linear semigroups of degree 2, 3 or 4. Certain results supporting the general conjecture are obtained. As the main tool, a new combinatorial property of groups is introduced and studied. 相似文献
156.
Genivaldo Júlio Perptuo Jan Janczak 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(7):o372-o375
Crystals of 2,4,6‐triamino‐1,3,5‐triazine‐1,3‐dium bis(trifluoroacetate) trihydrate, C3H8N62+·2CF3COO−·3H2O, and 2,4,6‐triamino‐1,3,5‐triazine‐1,3‐dium bis(trichloroacetate) dihydrate, C3H8N62+·2CCl3COO−·2H2O, both contain doubly protonated melamine rings that lie on crystallographic twofold axes. In the former structure, one water molecule also lies on a twofold axis. While the trifluoroacetate compound crystallizes in a centrosymmetric space group, the trichloroacetate is non‐centrosymmetric, so it is useful as a material for non‐linear optics. The efficiency of second harmonic generation is about three times greater than that of KDP (KH2PO4). A combination of ionic and donor–acceptor hydrogen‐bond interactions link the melaminium(2+) residues with trifluoroacetate or trichloroacetate ions and water molecules to form a three‐dimensional network. 相似文献
157.
McIntyre H. Wendell D. Lin K.J. Kaushik P. Seshadri S. Wang A. Sundararaman V. Ping Wang Song Kim Hsu W.-J. Hee-Choul Park Levinsky G. Jiejun Lu Chirania M. Heald R. Lazar P. Dharmasena S. 《Solid-State Circuits, IEEE Journal of》2005,40(1):52-59
A 4-MB L2 data cache was implemented for a 64-bit 1.6-GHz SPARC(r) RISC microprocessor. Static sense amplifiers were used in the SRAM arrays and for global data repeaters, resulting in robust and flexible timing operation. Elimination of the global clock grid over the SRAM array saves power, enabled by combining the clock information with array select signals. Redundancy was implemented flexibly, with shift circuits outside the main data array for area efficiency. The chip integrates 315 million transistors and uses an 8-metal-layer 90-nm CMOS process. 相似文献
158.
Hao Yin Chuang Lin Berton Sebastien Bo Li Geyong Min 《International Journal of Communication Systems》2005,18(8):711-729
Fast and accurate methods for predicting traffic properties and trend are essential for dynamic network resource management and congestion control. With the aim of performing online and feasible prediction of network traffic, this paper proposes a novel time series model, named adaptive autoregressive (AAR). This model is built upon an adaptive memory‐shortening technique and an adaptive‐order selection method originally developed by this study. Compared to the conventional one‐step ahead prediction using traditional Box–Jenkins time series models (e.g. AR, MA, ARMA, ARIMA and ARFIMA), performance results obtained from actual Internet traffic traces have demonstrated that the proposed AAR model is able to support online prediction of dynamic network traffic with reasonable accuracy and relatively low computation complexity. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
159.
160.
Chii-Wann Lin Kuo-Ping Chen Ming-Chii Su Chih-Kung Lee Chih-Chung Yang 《Optical and Quantum Electronics》2005,37(13-15):1423-1437
We have reported a novel design of surface plasmon resonance (SPR) device, which uses alternating dielectric layers to enhance the SPR signal quality and modulate its resonant position. Admittance loci method of thin film design has been used in the design of such a device. The use of biomolecular thin film, such as DNAs or Porteins, in this design can result in resonant condition of wavelength changes as well. Bio-plasmonics is proposed for the research and development of novel devices, which use biomolecules as a part of the plasmon oscillation system to actively interact with nano/micro structure. 相似文献