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Organic and polymeric driving circuits may be a possible alternative to realize low cost flexible and large area flat panel displays. Recent efforts have been directed to the discovery of solution processable polymeric semiconductors for the ease of fabrication and low cost. In this paper, we report the investigation of various 3‐substituted regioregular polythiophenes as active semiconductors for field‐effect transistors. The best transistor performance has been found with regioregular poly(3‐heaxylthiophene). The difference in their device performance was correlated to the structure and morphological behavior of these regioregular polythiophenes.  相似文献   
885.
The reaction of CuCN and KCN with (NH4)2[WS4] followed by cation exchange with PPh4Br produced the title compound, (C24H20P)2[Cu2WS4(CN)2]·CH3CN·H2O or (PPh4)2[(NC)Cu(μ‐S)2W(μ‐S)2Cu(CN)]·MeCN·H2O. In the structure of the dianion, [(NC)Cu(μ‐S)2W(μ‐S)2Cu(CN)]2−, the WS4 moiety acts as a bidentate ligand that binds two CuCN groups, thus forming a slightly bent WCu2 core with approximate D2d symmetry. The W—Cu distances are in the range 2.6463 (6)–2.6545 (6) Å.  相似文献   
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887.
摩托车正时链和传动链磨损特性的研究   总被引:6,自引:4,他引:6  
孟繁忠  赵富 《摩擦学学报》2000,20(2):106-109
研究油润滑条件下摩托车发动机正时链的磨损特性,发现疲劳磨损,裂纹的形成和扩展是影响疲劳寿命的主要因素;定期刷油或滴油润滑条件下,摩托车传动链的磨损机制是磨粒磨损,并伴有疲劳磨损,销轴和套筒零件的渗层及心部组织等是影响链条磨损特性的重要因素,因为中碳调质钢经碳氮共渗后可获得弥散分布的颗粒状碳化物的表层组织及回火屈氏体的心部组织,从而显示出表层耐磨、心部强韧性好及抗塑变能力高的综合机械性能。  相似文献   
888.
The Li3MX6 compounds (M=Sc, Y, In; X=Cl, Br) are known as promising ionic conductors due to their compatibility with typical metal oxide cathode materials. In this study, we have successfully synthesized γ-Li3ScCl6 using high pressure for the first time in this family. Structural analysis revealed that the high-pressure polymorph crystallizes in the polar and chiral space group P63mc with hexagonal close-packing (hcp) of anions, unlike the ambient-pressure α-Li3ScCl6 and its spinel analog with cubic closed packing (ccp) of anions. Investigation of the known Li3MX6 family further revealed that the cation/anion radius ratio, rM/rX, is the factor that determines which anion sublattice is formed and that in γ-Li3ScCl6, the difference in compressibility between Sc and Cl exceeds the ccp rM/rX threshold under pressure, enabling the ccp-to-hcp conversion. Electrochemical tests of γ-Li3ScCl6 demonstrate improved electrochemical reduction stability. These findings open up new avenues and design principles for lithium solid electrolytes, enabling routes for materials exploration and tuning electrochemical stability without compositional changes or the use of coatings.  相似文献   
889.
Mesoporous precious metals with abundant active sites and high surface area have been widely recognized as high‐performance catalytic materials. However, the templated synthesis is complex and costly. Herein, we report a mesoporous rhodium (m‐Rh) that can be readily synthesized from entangled nanofibres of Rh and Y2O3 without templates. The entangled nanofibres, prepared from uniform Rh‐Y alloys under redox atmosphere, were the key precursor in the synthesis processes. Moreover, the m‐Rh efficiently catalyzed carbon dioxide reforming of methane (DRM) at a low reaction temperature of 683 K. Further, electrochemical methods of CO electro‐oxidation were innovatively used to demonstrate the stability of CO and oxygen species for the DRM reaction.  相似文献   
890.
The state preparation operation of continuous-variable measurement-device-independent quantum key distribution (CV-MDI-QKD) protocol may become imperfect in practical applications. We address the security of the CV-MDI-QKD protocol based on imperfect preparation of the coherent state under realistic conditions of lossy and noisy quantum channel. Specifically, we assume that the imperfection of Alice's and Bob's practical state preparations equal to the amplification of ideal modulators and lasers at both Alice's and Bob's sides by untrusted third-parties Fred and Gray employing phase-insensitive amplifiers (PIAs), respectively. The equivalent excess noise introduced by the imperfect state preparation is comprehensively and quantitatively calculated by adopting the gains of PIAs. Security analysis shows that CV-MDI-QKD is quite sensitive to the imperfection of practical state preparation, which inevitably deteriorates the performance and security of CV-MDI-QKD system. Moreover, a lower bound of the secret key rate is derived under arbitrary collective attacks, and the upper threshold of this imperfection tolerated by the system is obtained in the form of the specific gains of PIAs. In addition, the methods presented will improve and perfect the practical security of CV-MDI-QKD protocol.  相似文献   
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