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941.
Frontispiece: Aromaticity Relocation in Perylene Derivatives upon Two‐Electron Oxidation To Form Anthracene and Phenanthrene
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The purpose of this paper is to study the dynamics of a monopolistic firm in a continuous-time framework. The firm is assumed to be boundedly rational and to experience time delays in obtaining and implementing information on output. The dynamic adjustment process is based on the gradient of the expected profit. The paper is divided into three parts: we examine delay effects on dynamics caused by one-time delay and two-time delays in the first two parts. Global dynamics and analytical results on local dynamics are numerically confirmed in the third part. Four main results are demonstrated. First, the stability switch from stability to instability occurs only once in the case of a single delay. Second, the alternation of stability and instability can continue if two time delays are involved. Third, the occurence of Hopf bifurcation is analytically shown if stability is lost. Finally, in a bifurcation process, there are a period-doubling cascade to chaos and a period-halving cascade to the equilibrium point in the case of two time delays if the difference between the two delays is large. 相似文献
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Organic light-emitting diodes (OLEDs) containing a transparent ultrathin layer of oxidized silver as a hole-injecting layer, placed between a indium–tin-oxide (ITO) electrode and the hole-transporting layer, were fabricated, and their electrical and luminescent properties were investigated. The OLEDs had a structure that consisted of an ITO layer; followed by an ultrathin Ag layer oxidized by a ultraviolet (UV)–ozone surface treatment; a N,N′-di-[(1-naphthyl)-N,N′-diphenyl]-1,1′-biphenyl)-4,4′-diamine (α-NPD) layer; a 5,6,11,12-tetraphenylnaphthacene (rubrene)-doped 9,10-diphenylanthracene (DPA) layer; a tris-(8-hydroxyquinoline) aluminum (Alq3) layer; a lithium fluoride (LiF) layer; and a Al layer. The operating voltages of the OLEDs with the oxidized Ag (i.e., AgOx) layer were drastically lower than those of the layer-free OLEDs, because the AgOx layer, which had high oxidizability, contributed to hole injection as it oxidized the surface of the α-NPD layer. However, the external quantum efficiency of the OLEDs with the AgOx layer was lower than that of the AgOx layer-free OLEDs, suggesting that the carrier balance (i.e., the balance between the holes and electrons) became uneven in the emission layer, owing to the insertion of the AgOx layer. It was assumed that this imbalance resulted from the number of holes in the emission layer being higher because of the increase in hole injection in the AgOx layer. 相似文献
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Dr. Graham N. Newton Dr. Norihisa Hoshino Dr. Takuto Matsumoto Dr. Takuya Shiga Prof. Motohiro Nakano Prof. Hiroyuki Nojiri Prof. Wolfgang Wernsdorfer Prof. Yuji Furukawa Prof. Hiroki Oshio 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(40):14205-14212
Here we report the synthesis, structure and detailed characterisation of three n‐membered oxovanadium rings, Nan[(V=O)nNan(H2O)n(α, β, or γ‐CD)2]?m H2O (n=6, 7, or 8), prepared by the reactions of (V=O)SO4?x H2O with α, β, or γ‐cyclodextrins (CDs) and NaOH in water. Their alternating heterometallic vanadium/sodium cyclic core structures were sandwiched between two CD moieties such that O‐Na‐O groups separated the neighbouring vanadyl ions. Antiferromagnetic interactions between the S=1/2 vanadyl ions led to S=0 ground states for the even‐membered rings, but to two quasi‐degenerate S=1/2 states for the spin‐frustrated heptanuclear cluster. 相似文献
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