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11.
Xinguang Zhang Lishan Liu Yonghong Wu 《Communications in Nonlinear Science & Numerical Simulation》2013,18(6):1400-1409
By using the fixed point theorem of the mixed monotone operator, the uniqueness of positive solution for a singular fractional differential system involving derivatives is established. An example is then given to illuminate the application of the main results. 相似文献
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A recursion formula for resistance distances is obtained, and some of its applications are illustrated. 相似文献
13.
Effects of preparation conditions of Au/FeO_x /Al_2O_3 catalysts prepared by a modified two-step method on the stability for CO oxidation 下载免费PDF全文
Composite oxide FeO x /Al 2 O 3 -supported gold catalysts were prepared by a modified two-step method. The effects of preparation conditions on the initial catalytic activity and long-time stability were studied for CO oxidation. XRD, XPS and in situ FTIR were employed to investigate the state of FeO x and the species on the catalyst surface. The results showed that Au/FeO x /Al 2 O 3 catalysts prepared by this method exhibited high activity and high stability in a wide pH value range. Calcination pretreatm... 相似文献
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Let G be a finite group. Fix a prime divisor p of IGI and a Sylow p-subgroup P of G, let d be the smallest generator number of P and Ma(P) denote a family of maximal subgroups P1, P2 , Pd of P satisfying ∩^di=1 Pi = Ф(P), the Frattini subgroup of P. In this paper, we shall investigate the influence of s-conditional permutability of the members of some fixed .Md(P) on the structure of finite groups. Some new results are obtained and some known results are generalized. 相似文献
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In this paper, we analyze a residual-type a posteriori error estimator of the finite volume element method for a quasi-linear elliptic problem of nonmonotone type and derive computable upper and lower bounds on the error in the H 1-norm. Numerical experiments are provided to illustrate the performance of the proposed estimator. 相似文献
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In this paper, firstly, a new mapping method is used to obtain the variable separation solutions, with two arbitrary functions, of the (2+1)-dimensional Boiti–Leon–Pempinelli equation. From the variable separation solution and by selecting appropriate functions, some novel Jacobian elliptic wave structure and periodic wave evolutional behaviors are investigated. 相似文献
20.
A bismuth/multi‐walled carbon nanotube (Bi/MWNT) composite modified electrode for determination of cobalt by differential pulse adsorptive cathodic stripping voltammetry is described. The electrode is fabricated by potentiostatic pre‐plating bismuth film on an MWNT modified glassy carbon (GC) electrode. The Bi/MWNT composite modified electrode exhibits enhanced sensitivity for cobalt detection as compared with the bare GC, MWNT modified and bismuth film electrodes. Numerous key experimental parameters have been examined for optimum analytical performance of the proposed electrode. With an adsorptive accumulation of the Co(II)‐dimethylglyoxime complex at ?0.8 V for 200 s, the reduction peak current is proportional to the concentration of cobalt in the range of 4.0×10?10?1.0×10?7 mol/L with a lower detection limit of 8.1×10?11 mol/L. The proposed method has been applied successfully to cobalt determination in seawater and lake water samples. 相似文献