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171.
172.
Positive results are derived concerning the long time dynamics of numerical simulations of stochastic differential equation systems with Markovian switching. Euler–Maruyama discretizations are shown to capture almost sure and moment exponential stability for all sufficiently small timesteps under appropriate conditions. 相似文献
173.
Lin Yikun Luo Xizhang Qiu Bingzheng Pang Xiao 《International Journal of Infrared and Millimeter Waves》1989,10(12):1427-1440
The optimum operating parameters of miniature OPFIRL was studied theoretically and experimentally. The theoretical results were in pretty good agreement with experimental results except for 1.5cm laser. The transverse feedback effect plays an important role in the miniature OPFIRL. it's worthv to be funther studied. 相似文献
174.
逆p·n·p·矩阵的表征 总被引:1,自引:0,他引:1
一个n阶实方阵A,若其各阶主子式皆非正,则称A为p.n.p.矩阵,记作A∈PNP;特别地,若A∈NP且各阶主子式皆负,则称A为p.n.矩阵,记作A∈PN进一步,若n阶实方阵A非奇异,且A-1∈PNP,则称A为逆p.n.p.矩阵,记作A∈IPNP;特别地,若A-1∈PN,则称A为逆p.n.矩阵,记作A∈IPN。 相似文献
175.
In this paper tests are derived for testing neighborhood hypotheses for the one- and multi-sample problem for functional data. Our methodology is used to generalize testing in projective shape analysis, which has traditionally involving data consisting of finite number of points, to the functional case. The one-sample test is applied to the problem of scene identification, in the context of the projective shape of a planar curve. 相似文献
176.
Chao Wang Felix S. Kim Guoqiang Ren Yongqian Xu Yi Pang Samson A. Jenekhe Li Jia 《Journal of polymer science. Part A, Polymer chemistry》2010,48(21):4681-4690
Head‐to‐tail regioregular poly(3‐heptanoylthiophene) (PHOT) was synthesized by Ni‐catalyzed polycondensation of the 2,2‐dimethyl‐1,3‐propanediol‐protected Grignard monomer followed by deprotection. Cyclic voltammetric (CV) study demonstrates that the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of PHOT are 0.5 eV lower in energy than those of the head‐to‐tail poly(3‐hexylthiophene) (HT‐P3HT). Their optical band gaps are essentially the same. Incomplete photoluminescence (PL) quenching was observed in thin films of the 1:1 blend of PHOT and HT‐P3HT. PHOT displayed a glass transition at ~269 °C and decomposed at ~300 °C according to differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Wide‐angle X‐ray diffraction (WAXD) study showed that PHOT exists in a not highly ordered state in solid films especially in the π‐stacking direction. Only p‐channel activity was observed in field‐effect transistors (FETs) for PHOT. The hole mobility was on the order of 10?4 cm2 V?1 s?1. Photovoltaic devices with an active layer of 1:1 blend of PHOT and PC71BM had a power conversion efficiency (PCE) of ~0.5%. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献
177.
178.
179.
DNA-modified electrodes (VII) 总被引:1,自引:0,他引:1
Qi Lu Daiwen Pang Shen Hu Jieke Cheng Xiongwei Cai Caihui Shi Bingwei Mao Hongping Dai 《中国科学B辑(英文版)》1999,42(4):425-432
Two kinds of DNA-modified electrodes were prepared by covalent and adsorptive immobilization of DNA onto self-assembled monolayers
of 2, 2’-dithiodiethanol on gold electrodes and characterized by cyclic voltammetry, X-ray photoelectron spectroscopy and
scanning tunneling microscopy. The results suggest that the methods are satisfactory for the immobilization of DNA on electrodes.
Project supported by the National Natural Science Foundation of China (Grant Nos. 39370213; 39770220; 29773034), State Key
Laboratory for Physical Chemistry of Solid Surfaces (Xiamen University), and Natural Science Foundation of Hubei Province
(Grant NO. 96J037). 相似文献
180.
Nonaqueous rechargeable lithium-air battery has so high specific capacity and specific energy that it is being widely researched by academia, corporation, and different research institutes. When used in dried air and absorbing oxygen form the air, this battery is called lithium-air battery, and its specific capacity based on cathode active material (oxygen) is infinite. However, its cycle performance is very limited as reported by the state-of-the-art researches. This cycle problem is mainly caused by instability of electrolyte. Based on electroanalysis of materials’ electrochemical property, a stable electrolyte solvent (sulfolane) and a lithium salt LiBF4 are selected as electrolytes in this work. Coupled with other eligible battery materials and careful assembly, the lithium-air battery exhibits favorable cycle performance. Above all, this lithium-air system is evaluated objectively in this paper. 相似文献