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101.
Structural Chemistry - Stacking interactions play an important role in stabilizing DNA and RNA secondary structure. To select a computational level to study the stacking interactions, both energy... 相似文献
102.
G. Leugering A. A. Novotny G. Perla Menzala J. Sokołowski 《Applied Mathematics and Optimization》2011,64(3):441-466
A shape optimization problem in three spatial dimensions for an elasto-dynamic piezoelectric body coupled to an acoustic chamber
is introduced. Well-posedness of the problem is established and first order necessary optimality conditions are derived in
the framework of the boundary variation technique. In particular, the existence of the shape gradient for an integral shape
functional is obtained, as well as its regularity, sufficient for applications e.g. in modern loudspeaker technologies. The
shape gradients are given by functions supported on the moving boundaries. The paper extends results obtained by the authors
in (Math. Methods Appl. Sci. 33(17):2118–2131, 2010) where a similar problem was treated without acoustic coupling. 相似文献
103.
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105.
Katarzyna Materna Wilhelm J. Tic Adam Sokołowski Wiesław Hreczuch 《Central European Journal of Chemistry》2011,9(2):300-307
A series of ethoxylates of 2,2,4-trimethyl-1,3-pentanediol mono-isobutyrate representing a synthetic C12 hydroxyester hydrophobe
was obtained. The solubility parameters, surface tension and critical micelle concentrations for model solutions were investigated.
The new surfactants were found to produce extremely low foam levels and a non-standard surface interfacial behavior was determined.
It was observed that the ethoxylates of the C12 hydroxyester formed an oriented monolayer at the interface regardless of their
average polyaddition degree. Such behavior is different from the surface activities of commonly known linear nonionic surfactants
and it indicates self organization of the surfactants at the interface. This feature offers possibility for application of
these surfactants in nanotechnology as well as in the conventional cleaning processes. 相似文献
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107.
Kamil Sokołowski Dr. Iwona Justyniak Dr. Witold Śliwiński Katarzyna Sołtys Adam Tulewicz Arkadiusz Kornowicz Prof. Dr. Robert Moszyński Prof. Dr. Janusz Lipkowski Prof. Dr. Janusz Lewiński 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(18):5637-5645
We report on investigations of reactions of tBu2Zn with 8‐hydroxyquinoline (q‐H) and the influence of water on the composition and structure of the final product. A new synthetic approach to photoluminescent zinc complexes with quinolinate ligands was developed that allowed the isolation of a series of structurally diverse and novel alkylzinc 8‐hydroxyquinolate complexes: the trinuclear alkylzinc aggregate [tBuZn(q)]3 ( 13 ), the pentanuclear oxo cluster [(tBu)3Zn5(μ4‐O)(q)5] ( 2 ), and the tetranuclear hydroxo cluster [Zn(q)2]2[tBuZn(OH)]2 ( 3 ). All compounds were characterized in solution by 1H NMR, IR, UV/Vis, and photoluminescence (PL) spectroscopy, and in the solid state by X‐ray diffraction, TGA, and PL studies. Density functional theory calculations were also carried out for these new ZnII complexes to rationalize their luminescence behavior. A detailed analysis of the supramolecular structures of 2 and 3 shows that the unique shape of the corresponding single molecules leads to the formation of extended 3D networks with 1D open channels. Varying the stoichiometry, shape, and supramolecular structure of the resulting complexes leads to changes in their spectroscopic properties. The close‐packed crystal structure of 13 shows a redshifted emission maximum in comparison to the porous crystal structure of 2 and the THF‐solvated structure of 3 . 相似文献
108.
Paulina Szczuka 《Mathematica Slovaca》2014,64(5):1153-1164
The main goal of this paper is to characterize the maximal class with respect to maximums for the family of upper semicontinuous strong ?wi?atkowski functions. 相似文献
109.
Alicyclobacillus acidoterrestris is a spore-forming bacterium, causing spoilage of juices. The spores of these bacteria have the ability to survive in the typical conditions used for thermal pasteurization. Therefore, the use of other techniques such as high hydrostatic pressure is considered for their inactivation. The effect of hydrostatic pressure of 200–500 MPa, at temperatures 4–50 °C for 15 min, on the dynamics of germination of A. acidoterrestris spores in apple juice and pH 4 buffer was studied. To estimate the share of germinated spores, the method of determining the optical density at a wavelength of 660 nm (OD660) was used. Parameters of hydrostatic pressure treatment used in this work affected the dynamics of germination of A. acidoterrestris spores in apple juice, and the temperature had the greatest effect. The results indicate that nutrients present in apple juice can promote the germination of A. acidoterrestris spores. 相似文献
110.
Paulina Szczuka 《Central European Journal of Mathematics》2013,11(5):876-881
In this paper we introduce a connected topology T on the set ? of positive integers whose base consists of all arithmetic progressions connected in Golomb’s topology. It turns out that all arithmetic progressions which are connected in the topology T form a basis for Golomb’s topology. Further we examine connectedness of arithmetic progressions in the division topology T′ on ? which was defined by Rizza in 1993. Immediate consequences of these studies are results concerning local connectedness of the topological spaces (?, T) and (?, T′). 相似文献