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41.
Gwang Hui Kim 《Journal of Mathematical Analysis and Applications》2004,299(2):375-391
In this paper we investigate a generalization of the Hyers-Ulam-Rassias stability for a functional equation of the form f(φ(X))=?(X)f(X)+ψ(X) and the stability in the sense of Ger for the functional equation of the form f(φ(X))=?(X)f(X), where X lie in n-variables. As a consequence, we obtain a stability result in the sense of Hyers-Ulam-Rassias, Gǎvruta, and Ger for some well-known equations such as the gamma, beta, and G-function type's equations. 相似文献
42.
LI Na ZHAO Degang & YANG Hui State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing China 《中国科学G辑(英文版)》2004,47(6):694-701
Because of their large band-gap, large high-field electron velocity, large breakdownfield, and large thermal conductivity, GaN and its heterojunction with AlGaN and InGaNhave foreseeable potential in the applications of high-power/temperature electronics, andoptoelectronic devices operative in UV and visible wavelength. Polarization inducedelectric field can reach the magnitude of ~MV/cm[1,2]. For AlGaN/GaN based FETs theconcentration of sheet carrier induced by polarization in the cha… 相似文献
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QiaoHongYAO FuYouLI LuSHAN ChunHuiHUANG DongDongYIN 《中国化学快报》2003,14(11):1185-1188
A new photoresponsive D-π-A dye, mPS, has been designed and synthesized.Compared to the parent dye PS, IPCE values in the region from 400 nm to 560 nm was greatly improved upon changing the attaching group from the p- position to the o- position of the π-conjugation bridge. A solar cell based on mPS generated a remarkably high overall yield η of 5.4% under irradiation of 80.0 mW cm^-2 white light from a Xe lamp, Compared with PS, the overall yield η increased by 64%. 相似文献
45.
We report the effects of post-thermal treatment on the quality of 2-inch 6H-SiC wafer cut from a crystal boule grown by physical vapour transportation method. The full widths at half maximum of x-ray diffraction rocking curves measured on sites across the 2-inch wafer become narrower, indicating the quality improvement after a three-step post-thermal treatment. It is found that the most common defects such as micropipes and inclusions can be significantly reduced after the treatment. Our results show that the post-thermal treatment is an effective route to improve the quality of SiC single crystals. 相似文献
46.
Wei‐Lie Xiao Jian‐Xin Pu Rui‐Rui Wang Liu‐Meng Yang Xiao‐Li Li Sheng‐Hong Li Rong‐Tao Li Sheng‐Xiong Huang Yong‐Tang Zheng Han‐Dong Sun 《Helvetica chimica acta》2007,90(8):1505-1513
Seven new highly oxygenated nortriterpenoids, rubriflorins D–J ( 1 – 7 ), were isolated from the leaves and stems of Schisandra rubriflora, and their structures were elucidated on the basis of extensive analysis of spectroscopic data. These new compounds feature the opening of ring A compared with related known nortriterpenoids isolated from the genus Schisandra and showed weak activity against HIV‐1. 相似文献
47.
Fa‐Yan Meng Xu‐Qing Liu Seik Weng Ng 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(7):m341-m342
The terephthalate dianion and the bis(imidazolyl)benzene ligand of the title compound, {[Zn(C8H4O4)(C20H14N4)]·C2H6O}n, each bridges two adjacent zinc centers, resulting in a layer‐type coordination polymer; the zinc center shows tetrahedral coordination. The disordered ethanol solvent molecules occupy the spaces between the layers and are hydrogen bonded to the layers. The two symmetry‐independent dianions lie on different inversion sites. 相似文献
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J. Xu Y. Z. Meng S. J. Wang A. S. Hay 《Journal of polymer science. Part A, Polymer chemistry》2006,44(10):3328-3335
A series of novel soluble pyridazinone‐ or pyridazine‐containing poly(arylene ether)s were prepared by a polycondensation reaction. The pyridazinone monomer, 6‐(4‐hydroxyphenyl)pyridazin‐3(2H)‐one ( 1 ), was synthesized from the corresponding acetophenone and glyoxylic acid in a simple one‐pot reaction. The pyridazinone monomer was successfully copolymerized with bisphenol A (BPA) or 1,2‐dihydro‐4‐(4‐hydroxyphenyl)phthalazin‐1(2H)‐one (DHPZ) and bis(4‐fluorophenyl)sulfone to form high‐molecular‐weight polymers. The copolymers had inherent viscosities of 0.5–0.9 dL/g. The glass‐transition temperatures (Tg's) of the copolymers synthesized with BPA increased with increasing content of the pyridazinone monomer. The Tg's of the copolymers synthesized from DHPZ with different pyridazinone contents were similar to those of the two homopolymers. The homopolymers showed Tg's from 202 to 291 °C by differential scanning calorimetry. The 5% weight loss temperatures in nitrogen measured by thermogravimetric analysis were in the range of 411–500 °C. 4‐(6‐Chloropyridazin‐3‐yl)phenol ( 2 ) was synthesized from 1 via a simple one‐pot reaction. 2 was copolymerized with 4,4′‐isopropylidenediphenol and bis(4‐fluorophenyl)sulfone to form high‐Tg polymers. The copolymers with less than 80 mol % pyridazinone or chloropyridazine monomers were soluble in chlorinated solvents such as chloroform. The copolymers with higher pyridazinone contents and homopolymers were not soluble in chlorinated solvents but were still soluble in dipolar aprotic solvents such as N‐methylpyrrolidinone. The soluble polymers could be cast into flexible films from solution. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3328–3335, 2006 相似文献