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131.
Electric fields can induce mechanical vibrations in planar aligned sandwich cells of ferroelectric liquid crystals. Measurements on a polysiloxane and a polyacrylate side chain polymer proved that the electromechanical effect also exists in ferroelectric liquid crystalline polymers. The main characteristics of the electromechanical responses of these polymers are described and compared to the response of low molecular weight ferroelectric liquid crystals. According to the proposed interpretation, the vibrations in the direction parallel to both the smectic layers and cell substrates are due to coupling between the director rotation and the flow, while the resonances in the vibrations normal to the plates are connected to layer deformations. 相似文献
132.
Kéki S Szilágyi LS Deák G Zsuga M 《Rapid communications in mass spectrometry : RCM》2003,17(8):783-787
A detailed investigation of the most commonly used plasticizers, such as phthalate, adipate and trimellitate esters, using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and post-source decay (PSD) MALDI-TOFMS/MS is described. It is shown that PSD MALDI-TOFMS/MS is capable of unambiguous determination of the different types of plasticizers. The determination of the types of plasticizers from different PVC samples by PSD MALDI-TOFMS/MS, without the need for solvent extraction, is also demonstrated. The fragmentation mechanisms of these plasticizers cationized with protons and sodium ions are also reported. 相似文献
133.
Csaba Várhelyi Magda Somay Antal Koch Ernő Grünwald 《Monatshefte für Chemie / Chemical Monthly》1978,109(6):1311-1320
Some new ligand exchange reactions of [Co(diph·H)2Cl(H2O)] and [Co(diph·H)2(SO3)(H2O)]– complexes with N3
–, S2O3
2– and with aromatic and heterocyclic amines were carried out. A series of derivatives of the types [Co(diph·H)2(SO3)X]
n–
(X=N3
–, S2O3
2– oramine) and [Co(diph·H)2(S2O3)2]3– were described and characterized. Some structural problems are resolved and discussed on the basis of UV and IR spectral data. 相似文献
134.
K. Kovács A. A. Kamnev E. Kuzmann Z. Homonnay P. Á. Szilágyi V. K. Sharma A. Vértes 《Journal of Radioanalytical and Nuclear Chemistry》2005,266(3):513-517
Summary This paper describes the M?ssbauer investigations of iron(III) salts in aqueous solutions in the presence of indole-3-alkanoic
acid ligands. The measurements showed two parallel reactions between the ligands and ferric ions: a complex formation and
a redox process. The oxidation process takes place in the ligands, and a part of Fe3+is reduced to Fe2+. 相似文献
135.
136.
P. Szilágyi 《Acta Mathematica Hungarica》1998,81(1-2):125-139
Different types of linear inequality systems have different consequence inequalities. Investigating several types of linear inequality systems, the present paper gives explicitly those consequences of the given system of linear inequalities that are all consistent if and only if the original system is consistent. Our results generalize the well-known Kuhn-Fourier theorem, and present important particular cases. 相似文献
137.
Madalina Barbaiani Cristina Bibire Jürgen Dassow Aidan Delaney Szilárd Fazekas Mihai Ionescu Guangwu Liu Atif Lodhi Benedek Nagy 《Journal of Applied Mathematics and Computing》2006,22(1-2):21-38
Programmed grammars, one of the most important and well investigated classes of grammars with context-free rules and a mechanism controlling the application of the rules, can be described by graphs. We investigate whether or not the restriction to special classes of graphs restricts the generative power of programmed grammars with erasing rules and without appearance checking, too. We obtain that Eulerian, Hamiltonian, planar and bipartite graphs and regular graphs of degree at least three are pr-universal in that sense that any language which can be generated by programmed grammars (with erasing rules and without appearance checking) can be obtained by programmed grammars where the underlying graph belongs to the given special class of graphs, whereas complete graphs, regular graphs of degree 2 and backbone graphs lead to proper subfamilies of the family of programmed languages. 相似文献
138.
We study the first-passage properties of a random walk in the unit interval in which the length of a single step is uniformly distributed over the finite range [−a,a]. For a of the order of one, the exit probabilities to each edge of the interval and the exit time from the interval exhibit anomalous properties stemming from the change in the minimum number of steps to escape the interval as a function of the starting point. As a decreases, first-passage properties approach those of continuum diffusion, but non-diffusive effects remain because of residual discreteness effects.
PACS: 02.50.C2, 05.40.Fb 相似文献
139.
Molnáir Z Nagy M Aranyi A Hanák L Argyelán J Pencz I Szánya T 《Journal of chromatography. A》2005,1075(1-2):77-86
Authors have constructed an automatized four-column large laboratory scale (I.D. = 50 mm, L = 500 mm) simulated moving bed (SMB) equipment. The applied model system for separation of biomolecules is glycine, L-phenylalanine, water and Sepabeads SP825 adsorbent. The authors determined the adsorption equilibrium data and the packing characteristics. The operating conditions of SMB equipment were calculated with the help of the Morbidelli variables. During the SMB experiments, glycine and L-phenylalanine were separated in water on Sepabeads SP825 with an average particle size 0.3 mm at temperatures 20 degrees C and 60 degrees C. The measurement series were carried out on a four-column three-zone open loop SMB. Both L-phenylalanine and glycine were produced with more than 99.9% (m/m) purity and 99% yield at productivity 1.7-3.7, with productivity 3.7-8.1 mg/(g adsorbent h) in case of 2-1-1-0 column configuration. The measured and the calculated data agreed well. 相似文献
140.
Kalász H Szücs Z Tihanyi M Szilágyi A Lengyel J 《Journal of chromatography. A》2005,1079(1-2):208-212
Nepsilon-Monomethyllysine was identified in the serum, urine, brain, and liver samples of rats treated per os with L-deprenyl. The identification procedure included reaction with Fmoc chloride, clean-up, and analysis using HPLC-UV-MS. Oral administration of (-)-N-14C-methyl-N-propynyl(2-phenyl-1-methyl)ethylammonium hydrochloride L-deprenyl) to rats resulted in transfer of the radiolabelled methyl group to the Nepsilon-amino group of the endogenous lysine. The radiolabelled Nepsilon-monomethyllysine was urinary eliminated together with the other radiolabelled deprenyl metabolites, such as deprenyl-N-oxide and methamphetamine. The presence of Nepsilon-monomethyllysine has also been traced, and its concentrations were compared in the serum, liver and brain of rats subjected to L-deprenyl treatment. Methyl group transfer from the L-deprenyl to endogenous compounds; and the urinary elimination of their products may offer a vital way to eliminate or to decrease the degree of drug transmethylation to the lysine constituents of blood vessels' proteins. 相似文献