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41.
Andrzej Smajdor 《Results in Mathematics》1994,26(3-4):385-389
A set-valued function F defined on a convex cone S in a real vector space X into the set n(Y) of all non-empty subsets of a real vector space Y is said to be the Jensen function iff $${1\over 2}\lbrack F(x)+F(x)\rbrack=F\lbrack{1\over 2}(x+y)\rbrack$$ for all x, y ∈ S. This note deals with iteration semigroups of Jensen set-valued functions on S. 相似文献
42.
43.
Summary It is shown that every convex set-valued function defined on a cone with a cone-basis in a real linear space with compact values in a real locally convex space has an affine selection. Similar results can be obtained for midconvex set-valued functions. 相似文献
44.
45.
Andrzej Machocki Tadeusz Borowiecki Andrezej Denis 《Reaction Kinetics and Catalysis Letters》1993,51(2):541-545
The studies of the influence of the kind of natural calcium mineral and the kind and amount of sodium promoter on the conversion degree of methane and oxygen, selectivity and yield of the oxidative conversion of methane have shown the usability of limestone as a basic component of the catalyst for this process. 相似文献
46.
We use an idea of countable separability of points and sets in topological spaces to prove results on intersection of measurable
multifunctions and an implicit function theorem. We generalize or extend in part some well known Himmelberg's theorems. 相似文献
47.
A planar ordered set has a triangle-free, planar covering graph; on the other hand, there are nonplanar ordered sets whose covering graphs are planar. We show thatevery triangle-free planar graph has a planar upward drawing. This planar upward drawing can be constructed in time, polynomial in the number of vertices.Our results shed light on the apparently difficult problem, of long-standing, whether there is aneffective planarity-testing procedure for an ordered set.Supported in part by the Alexander von Humboldt Stiftung.Supported in part by the Deutsche Forschungsgemeinschaft. 相似文献
48.
The palladium catalysed cross-coupling reaction of aryl iodides and bromides with pinacolborane in 1,3-dialkylimidazolium tetrafluoroborates and hexafluorophosphates producing arylboronates is described. 相似文献
49.
Many-body perturbation theory is used for the calculation of the quadrupole polarizability of the Be atom within the finite-field perturbation scheme. The correlation corrections exhibit a considerable dependence on the f-type orbital exponents and the final results are in the range 287–294 au. The convergence of the correlation perturbation series is discussed. 相似文献
50.
Zenon Lukaszewski Andrzej Szymanski Bogdan Wyrwas 《Trends in analytical chemistry : TRAC》1996,15(10):1239-531
The evolution of the BiAS procedure is reviewed and its standard recommended version was compared with the modified version combined with the indirect tensammetric method (BiAS-ITM). New applications of the use of BiAS-ITM for the determination of nonionic surfactants (in the presence of hydrocarbons or adsorbed on particles) and polyethylene glycols were discussed. 相似文献