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Ohne Zusammenfassung 相似文献
24.
Milo? Luká? Ivan Lacko Marián Bukovsky Zuzana Kyselová Janka Karlovská Branislav Horváth Ferdinand Devínsky 《Central European Journal of Chemistry》2010,8(1):194-201
We synthesized nine quaternary ammonium compounds (QUATs) starting from phenylalanine, N-alkyl-N,N-dimethyl-(1-hydroxy-3-phenylpropyl)-2-ammonium bromides, which were prepared as optically pure substances. Five compounds
were prepared as S-enantiomers and four compounds as R-enantiomers. These compounds were evaluated by their activities against bacteria and fungi. Three microbial strains were
used in the study: the gram-negative bacteria Escherichia coli, the gram-positive bacteria Staphylococcus aureus and the fungi Candida albicans. The activities were expressed as minimum bactericidal or fungicidal concentrations (MBC). The most active compounds were
(2S)-N-tetradecyl-N,N-dimethyl-(1-hydroxy-3-phenylpropyl)-2-ammonium bromide and (2R)-N-tetradecyl-N,N-dimethyl-(1-hydroxy-3-phenylpropyl)-2-ammonium bromide, with MBC values exceeding those of commercial benzalkoniumbromide
(BAB) used as standard. The relationships between structure and biological activity of the tested QUATs were quantified by
the bilinear model (QSAR) and are discussed. 相似文献
25.
We present a device which modifies the heat-pipe oven in such a way that the molecular number density can be drastically reduced. The device is essentially a small chamber with an independent internal heater inserted into the center of the ordinary linear heat-pipe oven which, in turn, serves as a reservoir of the liquid metal. The advantage of the present design of superheating within the heat-pipe oven, where temperature differences of several hundreds degrees centigrade were obtained, is shown in the case of far blue wings of the first self-broadened potassium resonance lines. 相似文献
26.
Zeitschrift für Physik C Particles and Fields - Electromagnetic as well as strong interactions play a significant role in the elastic scattering of unpolarized charged hadrons. One can... 相似文献
27.
Miloš Mladenović 《Monatshefte für Chemie / Chemical Monthly》1932,59(1-2):7-15
Ohne Zusammenfassung 相似文献
28.
Jánošíková L’udmila Herda Miloš Haviar Michal 《Central European Journal of Operations Research》2017,25(3):651-664
Central European Journal of Operations Research - The paper suggests two ways of combining a genetic algorithm with integer programming to improve the quality of the problem solution. The... 相似文献
29.
V. A. Andreev D. M. Davidović L. D. Davidović Milena D. Davidović Miloš D. Davidović 《Theoretical and Mathematical Physics》2017,192(1):1080-1096
We consider scale transformations (q, p) → (λq, λp) in phase space. They induce transformations of the Husimi functions H(q, p) defined in this space. We consider the Husimi functions for states that are arbitrary superpositions of n-particle states of a harmonic oscillator. We develop a method that allows finding so-called stretched states to which these superpositions transform under such a scale transformation. We study the properties of the stretched states and calculate their density matrices in explicit form. We establish that the density matrix structure can be described using negative binomial distributions. We find expressions for the energy and entropy of stretched states and calculate the means of the number-ofstates operator. We give the form of the Heisenberg and Robertson–Schrödinger uncertainty relations for stretched states. 相似文献
30.
Miloš Cabala Kateřina Veltruská Vladimír Matolín 《Surface and interface analysis : SIA》2011,43(12):1539-1542
Silver has rarely been considered as the catalyst for CO oxidation, although it has been recognized to be very active in several partial oxidation reactions such as ethylene epoxidation and formaldehyde synthesis. It is generally believed that a metal support interaction plays an important role in catalytic processes. Therefore in our study, we examined electronic and adsorption properties of cerium deposited onto a polycrystalline silver substrate. Layers of approximately one monolayer of cerium deposited on a clean silver substrate were examined in situ using surface‐sensitive techniques—by XPS, ultraviolet photoelectron spectroscopy (UPS) and low energy ion scattering (LEIS). CO molecular adsorption was observed by UPS and LEIS; experimental results exhibited CO adsorption on Ce atoms sites. Oxygen adsorption on deposited layers led to a strong oxidation; stoichiometry of oxidized layers was given by amount of adsorbed oxygen and by temperature. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献