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951.
952.
Slater sum for an inhomogeneous liquid of Fermions generated by a sech2 x potential in one dimension
《Physics and Chemistry of Liquids》2012,50(2):285-287
In one dimension, the Slater sum S(x, β), which is the diagonal element of the canonical density matrix, satisfies a known partial differential equation characterised by a one-body potential V(x). Here, for the case of a sech2 x potential in one dimension, it is stressed that S(x, β) is explicitly related to the limit S 0(β) as V(x) → 0 and to V(x) itself. This is the same input information as in the Thomas–Fermi result. The relevance to density functional theory is emphasised. 相似文献
953.
954.
Laurine R. ZuppVeronica L. Campanella DiAndra M. RudzinskiFrançois Beland Ronny Priefer 《Tetrahedron letters》2012,53(39):5343-5346
Microwave irradiation is a popular method in organic synthesis to achieve high yields in shorter reaction times. This decreases total ‘man-hours’ in a synthetic setting. Another technique used in organic chemistry to decrease manual manipulations, is solid support reagents. The benefits of this approach is that upon completion of a reaction, a simple filtration can be performed which expedites the work-up and also produces less organic waste. Friedel-Crafts alkylation has been explored using microwave chemistry as well as with solid-supported reagents. In comparison with traditional heating, as well as with AlCl3, superior yields were observed with silica-gel bound aluminum chloride (Si-AlClx) when microwave irradiated for only 5 min. 相似文献
955.
In this paper, we establish new Lyapunov-type inequalities for two classes of one-dimensional quasilinear elliptic systems of resonant type, which improve the recent results of Tang and He [X.H. Tang, X. He, Lower bounds for generalized eigenvalues of the quasilinear systems, J. Math. Anal. Appl. 385 (2012) 72-85] when 1 < pi < 2 for i = 1, 2, … , n. 相似文献
956.
The Multi-Commodity k-splittable Maximum Flow Problem consists in routing as much flow as possible through a capacitated network such that each commodity uses at most k paths and the capacities are satisfied. The problem appears in telecommunications, specifically when considering Multi-Protocol Label Switching. The problem has previously been solved to optimality through branch-and-price. In this paper we propose two exact solution methods both based on an alternative decomposition. The two methods differ in their branching strategy. The first method, which branches on forbidden edge sequences, shows some performance difficulty due to large search trees. The second method, which branches on forbidden and forced edge sequences, demonstrates much better performance. The latter also outperforms a leading exact solution method from the literature. Furthermore, a heuristic algorithm is presented. The heuristic is fast and yields good solution values. 相似文献
957.
958.
This review focuses on polymers with upper critical solution temperature (UCST) in water or electrolyte solution and provides a detailed survey of the yet few existing examples. A guide for synthetic chemists for the design of novel UCST polymers is presented and possible handles to tune the phase transition temperature, sharpness of transition, hysteresis, and effectiveness of phase separation are discussed. This review tries to answer the question why polymers with UCST remained largely underrepresented in academic as well as applied research and what requirements have to be fulfilled to make these polymers suitable for the development of smart materials with a positive thermoresponse. 相似文献
959.
《Analytical letters》2012,45(9):1831-1845
Abstract Immunohistochemical localization offers a fast and reliable method of obtaining information about the distribution of bound pesticide residues in plants. In the present study aquatic macrophytes (Elodea canadensis, Myriophyllum spicatum) were grown in laboratory model ecosystems spiked with 50 μg/l atrazine. To label cryosections, monoclonal antibodies from cell culture supernatants and ascites fluid with differing specificities for s-triazines were used in combination with the fluorescent dye Phycoerythrin and biotin-streptavidin amplification. The best results were observed with antibodies gained from mice immunized with an ametryn sulfoxide-BSA conjugate, regardless of the method employed for antibody production. The consequences with respect to herbicide metabolism and binding are discussed. 相似文献
960.
HONG BAO-JIAN 《东北数学》2012,28(1)
In this paper,a new generalized Jacobi elliptic function expansion method based upon four new Jacobi elliptic functions is described and abundant solutions of new Jacobi elliptic functions for the gene... 相似文献