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61.
一类具有有界扰动的非线性系统的输出反馈自适应控制 总被引:7,自引:1,他引:6
该文考虑一类具有有界干扰和未知参数的非线性系统(1),设计出一种用于输出跟踪的输出反馈鲁棒自适应控制器。该控制器能保证闭环系统的全局稳定性,并且解决了ε-跟踪问题。仿真结果表明,所设计的自适应控制器具有良好的跟踪性能。 相似文献
62.
Wei Shi Changshui Fang Qiwei Pan Qingtian Gu Xiangwen Wu Dong Xu Hongzhen Wei Xiaofeng Zhang Jinzhong Yu 《Optics and Lasers in Engineering》2001,35(5):309
The polyetherketone (PEK-c) guest–host system thin films in which the range of the weight percent of 3-(1,1-dicyanothenyl)-1-phenyl-4, 5-dihydro-1H-pyrazole (DCNP) is from 20% to 50% were prepared. Their corona poling temperatures were optimized by using the in situ second-harmonic generation (SHG) measurement. The high predicted value of electro-optical (EO) coefficient γ33=48.8 pm/v by using two-level model was obtained when the weight percent of DCNP in the polymer system is 40%, but EO coefficients are attenuated at higher chromophore loading than 40%. The temporal stability of the EO activity of the guest–host polymer was evaluated by probing the decay of the orientational order of the chromophores in the polymer system. 相似文献
63.
Li Y Wang N Gan H Liu H Li H Li Y He X Huang C Cui S Wang S Zhu D 《The Journal of organic chemistry》2005,70(24):9686-9692
[structure: see text] New perylene bisimide dyes bearing 3,5-bis(2-hydroxyphenyl)-1,2,4-triazole receptor units with different spacers have been synthesized and characterized. The fluorescence and electronic properties of these compounds have been studied. MALDI-TOF, UV-vis, and fluorescence titration experiments proved that monotopic perylene bisimide ligands could be assembled into dimmers by Fe(III) coordination. The coordination properties of the ditopic perylene bisimide ligands have also been studied preliminarily. Furthermore, the SEM images indicated that well-defined nanoscale structures could be fabricated by self-assembly due to metal ion coordination and pi-pi stacking interactions of perylene rings with the help of a proper spacer. 相似文献
64.
Ning Wang Yongjun Li Xiaorong He Haiyang Gan Yuliang Li Changshui Huang Xinhe Xu Jinchong Xiao Shu Wang Huibiao Liu Daoben Zhu 《Tetrahedron》2006,62(6):1216-1222
A new electrical and optical-active triad containing fullerene and perylenebisimide units has been prepared and characterized by UV-vis spectroscopy, fluorescence spectroscopy and voltammetry. For comparison, the triad containing only perylenebisimide units has also been studied. The SEM image indicated that uniform nanofibers of the triad were formed with a diameter of about 50 nm. The thin films of the triad produced steady and prompt photocurrent at irradiation of 20.0 mW cm−2 white light. 相似文献
65.
66.
Xuan Tang Feng Xue Hongju Ma Xiufang Cao Changshui Chen Xuegang Li 《Research on Chemical Intermediates》2013,39(3):805-820
A series of N-β-d-glucopyranosyl-N’-substituted phenyl ureas were synthesized by reaction of glucosyl isocyanate with arylamines and glycosamine with aryl isocyanates, and a series of d-glucofurano-imidazolidine-2-ones were obtained via deacetylation of glycosylureas. Although some of the compounds have already been described, most were prepared for the first time in this work. The structures of all the compounds synthesized were confirmed by IR, 1H NMR, and, in part, by 13C NMR. Antifungal activity of the title compounds was determined against four kinds of plant pathogenic fungi, Sclerotinia sclerotiorum, Fusarium graminearum, Fusarium oxysporum, and Bipolaris maydis. Preliminary bioassay indicates that most of glycosylureas had some activity against S. sclerotiorum; for some, the antifungal activity was strong. However, most of the imidazolidine-2-ones had weak antifungal activity. 相似文献
67.
Visible near-infrared chemosensor for mercury ion 总被引:2,自引:0,他引:2
A visible near-infrared chemosensor (MCy-1) for mercury ions was successfully devised and characterized. A large red-shift (122 nm) of the absorption maximum of MCy-1 was observed. An important feature for the new chemosensor is its high selectivity towards mercury ions over the other competitive species, making the "naked-eye" detection of mercury ions possible. 相似文献