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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
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Grzegorz Litak Davide Bernardini Arkadiusz Syta Giuseppe Rega Andrzej Rysak 《The European physical journal. Special topics》2013,222(7):1637-1647
Shape memory materials exhibit strong thermomechanical coupling, so that temperature variations occur during mechanical loading and unloading. In previous works the nonlinear dynamics of pseudoelastic oscillators subject to an harmonic force has been studied and the possibility of non-regular chaotic responses has been thoroughly documented. Instead of the standard Lyapunov exponent treatment, the statistical 0–1 test based on the asymptotic properties of a Brownian motion chain was successively applied to reveal the chaotic nature of trajectories in the special case in which temperature variations were neglected. In this work, the 0–1 test is applied to fully non-isothermal trajectories. To improve its reliability the test has been applied to the time-histories of maxima and minima of each trajectory, in each component. The obtained results have been validated and confirmed by the corresponding Fourier spectra. Non-regular solutions with different levels of chaoticity have been analyzed and their qualitative difference is reflected by the different values to which the control parameter K asymptotically converge. 相似文献
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Arkadiusz Płoski 《Central European Journal of Mathematics》2014,12(5):688-693
Let f = 0 be a plane algebraic curve of degree d > 1 with an isolated singular point at 0 ∈ ?2. We show that the Milnor number μ0(f) is less than or equal to (d?1)2 ? [d/2], unless f = 0 is a set of d concurrent lines passing through 0, and characterize the curves f = 0 for which μ0(f) = (d?1)2 ? [d/2]. 相似文献
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Sokołowski K Justyniak I Sliwiński W Sołtys K Tulewicz A Kornowicz A Moszyński R Lipkowski J Lewiński J 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(18):5637-5645
We report on investigations of reactions of tBu(2)Zn 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) (1(3)), the pentanuclear oxo cluster [(tBu)(3)Zn(5)(μ(4) -O)(q)(5)] (2), and the tetranuclear hydroxo cluster [Zn(q)(2)](2)[tBuZn(OH)](2) (3). All compounds were characterized in solution by (1)H 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 Zn(II) 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 1(3) 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
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Arkadiusz Mystkowski 《PAMM》2009,9(1):631-632
In this paper, the μ-Synthesis Control method is applied to control Active Magnetic Bearings (AMBs) Flywheel. The dynamics of the open-loop system is influenced by external disturbances, nonlinearities, uncertainties and signal limits. Thus, a design methodology, which covers the practical issues of optimal robust control like the modelling of uncertainties, selection of optimal weighting functions is presented. The goal of this paper is the experimental evaluation robust performance of the AMBs system. The laboratory stand with the high speed rotor supported magnetically was built and presented. The stable operation, good stiffness of the rotor suspension and robust performances of the closed-loop AMBs is reached. Finally, the success of the robust control is demonstrated through results of computer simulations and experimental results. The experimental results show the effectiveness of the control system as well as good vibrations reduction of the designed controllers. (© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献