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101.
102.
借助Nevanlinna理论,研究了Borel方向和解析函数的唯一性之间的关系,得到了几个在包含Borel方向的角域内分担四个不同值的解析函数的唯一性定理.这些结果是龙见仁和伍鹏程~([10])相关结果的推广. 相似文献
103.
Lidong Wang Xiaodong LiuWangren Qiu 《International Journal of Approximate Reasoning》2012,53(2):200-211
The approximation space model was originally proposed by Pawlak (1982) [19]. It was Or?owska who first observed that approximation spaces serves as a formal counterpart of perception, or observation [16, §2, p. 8], in which approximations provide a means of approximating one set of objects with another set of objects using the indiscernibility relation. Topology has been used to enrich the original model of an approximation space as well as more recent models of generalized approximation spaces. In this paper, an extension of th e topology neighborhood based on AFS (Axiomatic Fuzzy Sets) theory is introduced, and some interesting properties are given. Furthermore, a new generalized approximation space model is established with two application examples, which can be used to deal with information tables with many category features and viewed as a multi-granulations form of nearness approximation space models. 相似文献
104.
In this paper, we study the existence of least energy sign-changing solutions for a Kirchhoff-type problem involving the fractional Laplacian operator. By using the constraint variation method and quantitative deformation lemma, we obtain a least energy nodal solution ub for the given problem. Moreover, we show that the energy of ub is strictly larger than twice the ground state energy. We also give a convergence property of ub as b ↘ 0, where b is regarded as a positive parameter. 相似文献
105.
令\{$X$, $X_n$, $n\ge 1$\}是期望为${\mathbb{E}}X=(0,\ldots,0)_{m\times 1}$和协方差阵为${\rm Cov}(X,X)=\sigma^2I_m$的独立同分布的随机向量列, 记$S_n=\sum_{i=1}^{n}X_i$, $n\ge 1$. 对任意$d>0$和$a_n=o((\log\log n)^{-d})$, 本文研究了${{\mathbb{P}}(|S_n|\ge (\varepsilon+a_n)\sigma \sqrt{n}(\log\log n)^d)$的一类加权无穷级数的重对数广义律的精确速率. 相似文献
106.
本文以钛酸正四丁酯为前驱体采用溶胶凝胶法制备了稳定的TiO2溶胶,以可溶性的硝酸铝作为掺杂剂制备了Al2O3-TiO2复合薄膜。采用XRD分析了薄膜的晶相组成,AFM表征了薄膜表面粗糙度随着Al2O3添加量的增加而变化的趋势。XRD测试结果表明,随着Al2O3添加量的增加,薄膜中TiO2晶粒的平均尺寸逐渐减小;而AFM测试结果表明,薄膜表面粗糙度呈现减小的趋势,但是当Ti/Al比例增加到1∶0.12时,颗粒尺寸比1∶0.06时有所增大,这主要是由于包覆在TiO2晶粒表面的Al2O3非晶相增多导致颗粒聚集生长严重所致。 相似文献
107.
This paper deals with some uniqueness problems of entire functions concerning differential polynomials that share one value with finite weight in a different form. We obtain some theorems which generalize some results given by Banerjee, Fang and Hua, Zhang and Lin, Zhang, etc. 相似文献
108.
The poly(poly(ethylene glycol) methyl ether monomethacrylate) (PPEGMA) grafted zinc oxide (ZnO) nanoparticles were successfully prepared via the surface-initiated atom transfer radical polymerizations (ATRP) from the surfaces functionalized ZnO nanoparticles. The 2-bromoisobutyrate (BIB) was immobilized onto the surface of the ZnO nanoparticles through the reaction between 2-bromoisobutyryl bromide (BIBB) and the hydroxyl groups on nanoparticles, serving as the initiator to induce the ATRP of poly(ethylene glycol) monomethacrylate (PEGMA). Well-defined polymer chains were grown from the surfaces to yield hybrid nanoparticles comprised of ZnO cores and PPEGMA polymer shells having multifunctional end groups. The structure and morphology of the nanoparticles were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The optical properties of the nanoparticles were investigated by UV-vis absorption spectroscopy and photoluminescence spectroscopy (PL). The results showed that the dispersion and near-band edge (NBE) emission of ZnO nanoparticles could be improved by the grafted PPEGMA polymer segments. 相似文献
109.
The influence of SiO2 on the dielectric properties of barium titanate ceramics was investigated. SiO2 had been doped solely and together with BaO into barium titanate before calcination. X-ray diffraction showed that all the ceramics were of a pure perovskite phase after sintering at 1275 °C for 2 h. For SiO2-doping, there was about 2.5 °C increase in Curie temperature per molar percentage of doping and the leakage current was obviously increased, especially at low voltages for relatively high doping levels. While for the co-doping of SiO2 and BaO, there was little change in Curie temperature. The point defects formed through the dopings were proposed responsible for the effects. It was suggested that SiO2 is important to barium titanate ceramics not only for sintering but also for modifying their properties. 相似文献
110.
High scintillation efficiency of Eu-doped LiSrAlF6 (LiSAF) and LiCaAlF6 (LiCAF) codoped with alkali metal ions has been reported in our recent studies. Thus in this paper, we demonstrated the scintillation properties of 1% Ce-doped LiSAF crystals with 1% alkali metal ions co-doping to increase the light yield and understand the scintillation mechanism. The crystals showed intense emission band corresponding to the 5d-4f transition of Ce3+, and their light yields under thermal neutron excitation were higher than that of the Ce only doped crystal. Especially, the light yield of Ce–Na co-doped crystal exceeded about two times that of Ce only doped one. 相似文献