Some relations between certain inequalities concerning analytic and univalent functions

By making use of the well-known assertions in [S.S. Miller, P.T. Mocanu, Differential Subordinations, Theory and Applications, Marcel Dekker, New York-Basel, 2000] and [M. Nunokawa, On the order of strongly starlikeness of strongly convex functions, Proc. Japan Acad. Ser. A Math. Sci. 69 (7) (1993) 234–237], several useful results of certain inequalities dealing with analytic and univalent functions are obtained and then certain consequences of them are also indicated.     

Surface integral and Gauss-Ostrogradskij theorem from the viewpoint of applications

Making use of a surface integral defined without use of the partition of unity, trace theorems and the Gauss-Ostrogradskij theorem are proved in the case of three-dimensional domains with a Lipschitz-continuous boundary for functions belonging to the Sobolev spaces H ^1,p () (1 p < ). The paper is a generalization of the previous author's paper which is devoted to the line integral.     

Stability of Ritz procedure for nonlinear two-point boundary value problem

In this paper we establish the stability of Ritz procedure in sense of Michlin and Tucker for a class of nonlinear two-point boundary value problems which has been considered by Varga, Schultz and Ciarlet in [1].     

Bestimmung von Blei, Chrom, Kupfer und Nickel in Polyethylen mit der direkten Zeeman-Atomabsorptionsspektralphotometrie

Zusammenfassung Die Möglichkeiten der Bestimmung von Blei, Chrom, Kupfer und Nickel in Polyethylen mit der direkten Zeeman-AAS sind untersucht worden. Dabei wurde festgestellt, daß Blei bis 0,2%, Chrom bis 0,03%, Kupfer bis 0,05% und Nickel bis 0,06% in Polyethylen als Obergrenze bestimmt werden kann, indem Probestückchen von bis zu 1 mg direkt auf einer Mikrogrammwaage in ein Graphitschiffchen eingewogen werden. Die Analyse kann ohne chemische Vorbereitung durchgeführt werden. Die Feststoffanalyse ermöglicht gleichzeitig Studien zur Homogenität des Polyethylens.

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Determination of heavy metals (Pb, Cr, Cu, Ni) in polyethylene using direct Zeeman-AAS

Summary The determination of lead, copper, chromium and nickel in polyethylene by means of direct Zeeman-AAS was investigated. It has been found that lead up to 0.2% and Cr up to 0.03%, copper up to 0.05% and nickel up to 0.06% in polyethylene can be determined by weighing polyethylene up to 1 mg into a graphite boat by means of a microbalance. Putting the boat directly into the graphite furnace the analysis was done without chemical pretreatment. The solid sampling analysis technic by direct Zeeman-AAS allows homogeneity studies in polyethylene.

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Wir danken der Firma Bischof + Klein Verpackungswerke, Lengerich, für die Beschaffung von Rohstoffen zur Probenherstellung und Klaus Will vom Laborbereich Kunststofftechnologie des Fachbereichs Chemieingenieurwesen der Fachhochschule Münster für die Unterstützung bei der Probenherstellung.     

Synthesis,crystal structure and catalytic activity for H2O2 disproportionation of the manganese(II) coordination polymer {[Mn(O2C(CF2)8CO2)(phen)2]H2O}n (phen = 1,10-phenanthroline)

The title polymeric complex {[Mn(O₂C(CF₂)₈CO₂)(phen)₂]H₂O}_n was synthesized through the reaction of 1,10-phenanthroline, perfluorosebacic acid and MnCO₃ · H₂O. The molecular structure was characterized by X-ray diffraction, elemental analysis, thermal gravimetry, IR and UV–Vis spectroscopy and its catalytic activity has been studied. X-ray structure analysis shows that each Mn(II) ion is octahedrally coordinated by two bidentate phenanthroline ligands and the carboxylate oxygen atoms from two symmetry related perfluorosebacate ligands, which are coordinated in cisoid positions. The structure consists of polymeric chains, with the perfluorosebacato ligand bridging the Mn(II) ions in a monodentate fashion. Crystallographic characterization shows a supramolecular structure involving hydrogen bonds, π–π and π-ring interactions. The catalytic results indicated that the complex has reasonably good activity towards the disproportionation of hydrogen peroxide into water and dioxygen in methanol and it does not exhibit saturation kinetics with the substrate. The initial reaction rates and their temperature and base dependencies were investigated by monitoring the dioxygen evolution. Kinetic studies revealed a first-order dependence on the catalyst concentration. Activation parameters have been calculated at 301 K.