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251.
Visible‐light‐driven photocatalytic degradation of fenpyroximate in rotating packed bed reactor using Fe3O4@PbS@Ni2P magnetic nanocomposite photocatalyst: Response surface modelling and optimization 下载免费PDF全文
252.
Oscar Valero 《Proceedings Mathematical Sciences》2008,118(2):245-254
A quasi-normed cone is a pair (X, p) such that X is a (not necessarily cancellative) cone and q is a quasi-norm on X. The aim of this paper is to prove a closed graph and an open mapping type theorem for quasi-normed cones. This is done with
the help of appropriate notions of completeness, continuity and openness that arise in a natural way from the setting of bitopological
spaces. 相似文献
253.
We consider the space D(X, Y) of densely continuous forms introduced by Hammer and McCoy [5] and investigated also by Holá [6]. We show some additional
properties of D(X, Y) and investigate the subspace D*(X) of locally bounded real-valued densely continuous forms equipped with the topology of pointwise convergence τ-
p
. The largest part of the paper is devoted to the study of various cardinal functions for (D*(X), τ
p
), in particular: character, pseudocharacter, weight, density, cellularity, diagonal degree, π-weight, π-character, netweight etc.
This work was supported by Science and Technology Assistance Agency under the contract No. APVT-51-006904. The authors would
like to thank Ľubica Holá for suggestions and comments. 相似文献
254.
A. L. Kuz’mina 《Russian Mathematics (Iz VUZ)》2008,52(7):8-14
We study Besicovitch-type spaces of generalized almost periodic functions. The main result is a theorem on representation of linear continuous functionals that is similar to the classical result of F. Riesz. 相似文献
255.
高正晖 《数学的实践与认识》2008,38(11):178-183
研究了一类含连续分布滞量和阻尼项的非线性双曲型偏微分方程组运用黎卡提变换获得了该方程组在两类边值条件下解振动的充分条件. 相似文献
256.
提出一类新的广义向量拟均衡问题,并得到解的存在性定理.用于证明向量变分不等式和向量优化问题的解的存在性. 相似文献
257.
Let E be a real reflexive Banach space having a weakly continuous duality mapping Jφ with a gauge function φ, and let K be a nonempty closed convex subset of E. Suppose that T is a non‐expansive mapping from K into itself such that F (T) ≠ ??. For an arbitrary initial value x0 ∈ K and fixed anchor u ∈ K, define iteratively a sequence {xn } as follows: xn +1 = αn u + βn xn + γn Txn , n ≥ 0, where {αn }, {βn }, {γn } ? (0, 1) satisfies αn +βn + γn = 1, (C 1) limn →∞ αn = 0, (C 2) ∑∞n =1 αn = ∞ and (B) 0 < lim infn →∞ βn ≤ lim supn →∞ βn < 1. We prove that {xn } converges strongly to Pu as n → ∞, where P is the unique sunny non‐expansive retraction of K onto F (T). We also prove that the same conclusions still hold in a uniformly convex Banach space with a uniformly Gâteaux differentiable norm or in a uniformly smooth Banach space. Our results extend and improve the corresponding ones by C. E. Chidume and C. O. Chidume [Iterative approximation of fixed points of non‐expansive mappings, J. Math. Anal. Appl. 318 , 288–295 (2006)], and develop and complement Theorem 1 of T. H. Kim and H. K. Xu [Strong convergence of modified Mann iterations, Nonlinear Anal. 61 , 51–60 (2005)]. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
258.
In this communication, a porous stainless steel (PSS) tube was electrolessly plated into Pd–Ag membrane reactor which was used for separating hydrogen produced in an ethanol steam reforming reaction with the addition of oxygen, which has not been reported before. Palladium and silver were deposited on porous stainless steel tube via the sequential electroless plating procedure with an overall film thickness of 20 μm and Pd/Ag weight ratio of 78/22. Ethanol–water mixture (nwater/nethanol = 1 or 3) and oxygen (noxygen/nethanol = 0.2 or 0.7) were fed concurrently into the membrane reactor packed with MDC-3. The reaction temperatures were set at 593–723 K and the pressures 3–10 atm. The effect of oxygen addition plays a vital role on the ethanol steam reforming reaction, especially for the Pd–Ag membrane reactor in which a higher flux of hydrogen is required. If oxygen in the feed is not sufficient, it would be possible that steam reforming reaction prevails. Inversely, high O2 addition will shift the reaction scenario to be partial oxidation dominating, and selectivity of CO2 increases with increasing oxygen feed. At high pressure, autothermal reaction of ethanol would be easily reached. 相似文献
259.
The paper is devoted to a careful analysis of the shape-preserving properties of the strongly continuous semigroup generated
by a particular second-order differential operator, with particular emphasis on the preservation of higher order convexity
and Lipschitz classes. In addition, the asymptotic behaviour of the semigroup is investigated as well. The operator considered
is of interest, since it is a unidimensional Black-Scholes operator so that our results provide qualitative information on
the solutions of classical problems in option pricing theory in Mathematical Finance.
The paper is dedicated to Professor Luigi Albano on the occasion of his 70th birthday. 相似文献
260.
P. P. J. Van Den Bosch F. A. Lootsma 《Journal of Optimization Theory and Applications》1987,55(2):313-326
We investigate methods for solving high-dimensional nonlinear optimization problems which typically occur in the daily scheduling of electricity production: problems with a nonlinear, separable cost function, lower and upper bounds on the variables, and an equality constraint to satisfy the demand. If the cost function is quadratic, we use a modified Lagrange multiplier technique. For a nonquadratic cost function (a penalty function combining the original cost function and certain fuel constraints, so that it is generally not separable), we compare the performance of the gradient-projection method and the reduced-gradient method, both with conjugate search directions within facets of the feasible set. Numerical examples at the end of the paper demonstrate the effectiveness of the gradient-projection method to solve problems with hundreds of variables by exploitation of the special structure. 相似文献