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141.
In this paper, we are interested in the existence and multiplicity results of solutions for the singular quasilinear elliptic problem with concave–convex nonlinearities (0.1) where is an unbounded exterior domain with smooth boundary ?Ω, 1 < p < N,0 ≤ a < (N ? p) ∕ p,λ > 0,1 < s < p < r < q = pN ∕ (N ? pd),d = a + 1 ? b,a ≤ b < a + 1. By the variational methods, we prove that problem 0.1 admits a sequence of solutions uk under the appropriate assumptions on the weight functions H(x) and H(x). For the critical case, s = q,h(x) = | x | ? bq, we obtain that problem 0.1 has at least a nonnegative solution with p < r < q and a sequence of solutions uk with 1 < r < p < q and J(uk) → 0 as k → ∞ , where J(u) is the energy functional associated to problem 0.1 . Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
142.
利用K-集压缩算子拓扑度抽象连续定理,得到一类带分布时滞的中立型泛函微分方程存在周期解的充分条件. 相似文献
143.
也谈中学生自学能力的培养 总被引:1,自引:0,他引:1
利用自编学案诱导学生分步自学,培养学生的自学习惯;加强学生阅读能力的培养,结合物理学科知识的联系,让学生比较、归纳,促使学生掌握自学方法;强化信息题的训练,培养信息处理能力,实现自学能力的有效提升. 相似文献
144.
XIONG Zi-jun DU Peng LI Bian XU Li-li ZHEN Xue-chu FU Wei .Key Laboratory of Smart Drug Delivery Ministry of Education & PLA 《高等学校化学研究》2011,(4):655-660
The serotonin 2A(5-HT2A) receptor has been implicated in several neurological conditions and potent 5-HT2A antagonists have therapeutic effects in the treatment of schizo phrenia and depression.In this study,a potent novel 5-HT2A inhibitor 05245768 with a Ki value of (593.89±34.10) nmol/L was discovered by integrating a set of computational approaches and experiments(protein structure prediction,pharmacophore-based virtual screening,automated molecular docking and pharmacological bioassay).The 5-HT2A recept... 相似文献
145.
Fei Gao Bian‐Hong Meng Yi‐Bin Wei 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(7):m360-m362
The crystal structure of the title compound, [Mg(H2O)6]0.5[Mg2(C16H14ClN2O9)(H2O)4]·10H2O, shows that this binuclear complex consists of two Mg centres in distorted octahedral geometry, joined by an oxo bridge which is a derivative of the deprotoned hydroxy group of the phenolate in the ligand molecule. In the anion, the coordination sphere of each MgII ion is completed by two carboxylates, a tertiary N atom and two water molecules. The inner coordination spheres for the MgII ions are very similar, both in ligand sets and in geometry. Each unit of the binuclear complex has one negative charge neutralized by a neighbouring hydrated cation, [Mg(H2O)6]2+, in which the Mg atom lies on an inversion centre. In each cell, there are 34 water molecules and most of them participate in the formation of hydrogen bonds, which contribute greatly to the stability of the whole structure. 相似文献
146.
147.
Baojun Bian Min Dai Lishang Jiang Qing Zhang Yifei Zhong 《Journal of Optimization Theory and Applications》2011,151(2):402-417
This paper is concerned with liquidation of an illiquid stock. The stock price follows a fluid model which is dictated by the rates of selling and buying over time. The objective is to maximize the expected overall return. The method of constrained viscosity solution is used to characterize the dynamics governing the optimal reward function and the associated boundary conditions. Numerical examples are given to illustrate the results. 相似文献
148.
许丽芳 《广东微量元素科学》1999,6(6):34-35
任意取城镇6个月-7岁男女儿童220例,取其枕意味着不测定Zn、Fe、Ca、Pb的含量,分年龄,怀别统计其正常值,非正常值发生率。结果发现,缺锌,中发生率与年龄有关,缺Ca、高Ca发生率与年龄,性别有关。 相似文献
149.
Jin-Fang Nie Hai-Long Wu A-Lin Xia Shao-Hua Zhu Ying-Chao Bian Shu-Fang Li Ru-Qin Yu 《Analytical sciences》2007,23(12):1377-1382
This paper proposes a new and effective approach for the quantitative analysis of sulpiride, a significant antipsychotic drug, in human urine samples by the incorporation of excitation-emission matrix (EEM) fluorescence and second-order calibration methodologies based on the alternating fitting residue (AFR) and self-weighted alternating trilinear decomposition (SWATLD) algorithms. With the application of a second-order advantage, the proposed strategy could be utilized for a direct concentration determination of sulpiride with a simple pretreatment step, even in the presence of serious natural fluorescent interferences. The average recoveries of sulpiride in complex urine samples by using AFR and SWATLD with an estimated component number of three were 101.2 +/- 2.1 and 94.4 +/- 0.7%, respectively. Moreover, the accuracy of the two algorithms was also evaluated through elliptical joint confidence region (EJCR) tests as well as the figures of merit, such as sensitivity (SEN), selectivity (SEL) and limit of detection (LOD). The experimental results demonstrated that both algorithms, as promising quantitative alternatives, have been satisfactorily applied to the determination of sulpiride in human urine, but the performance of AFR was slightly better than that of SWATLD. 相似文献
150.
与正规性相关的各种子群之间的关系 总被引:5,自引:0,他引:5
本讨论了正规子群,拟正规子群,s-拟正规子群,半正规子群,c-正规子群,次正规子群,共轭置换子群,半置换子群,s-半置换子群这九种子群之间的关系。 相似文献