University of Chemistry and Technology is the largest university specializing in chemistry in the Czech Republic. It was founded in 1952 and since that time it has been one of the leading research spots in Central Europe. More than 2,000 students are accepted every year. Academic staff comprises 780 teachers including 84 professors, 119 associate professors and 265 assistant professors and 28 assistants.The university consists of four faculties: Faculty of Chemical Technology Faculty of Environmental Technology Faculty of Food and Biochemical Technology Faculty of Chemical Engineering ↑ 1.0 1.1 1.2 Wikipedia.
Malijevsky A.,Institute of Chemical Technology Prague |
Parry A.O.,Imperial College London
Physical Review Letters | Year: 2013
We present results of a microscopic density functional theory study of wedge filling transitions, at a right-angle wedge, in the presence of dispersionlike wall-fluid forces. Far from the corner the walls of the wedge show a first-order wetting transition at a temperature Tw which is progressively closer to the bulk critical temperature Tc as the strength of the wall forces is reduced. In addition, the meniscus formed near the corner undergoes a filling transition at a temperature Tf< Tw, the value of which is found to be in excellent agreement with macroscopic predictions. We show that the filling transition is first order if it occurs far from the critical point but is continuous if Tf is close to Tc even though the walls still show first-order wetting behavior. For this continuous transition the distance of the meniscus from the apex grows as ℓw≈(Tf-T) -βw with the critical exponent βw≈ 0.46±0.05 in good agreement with the phenomenological effective Hamiltonian prediction. Our results suggest that critical filling transitions, with accompanying large scale universal interfacial fluctuation effects, are more generic than thought previously, and are experimentally accessible. © 2013 American Physical Society.
Vanura P.,Institute of Chemical Technology Prague
Journal of Radioanalytical and Nuclear Chemistry | Year: 2010
From extraction experiments and y-activity measurements, the exchange extraction constants corresponding to the general equilibrium M2+(aq) + Sr2+(nb) ⇄ M2+(nb) + Sr2+(aq) taking part in the two-phase water-nitrobenzene system (M2+ = Mg 2+,Ca2+,Ba2+,Cu2+, Zn 2+,Cd2+,Pb2+,UO2+,Mn 2+,Fe2+,Co2+,Ni2+; aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Furthermore, the individual extraction constants of the M2+ cations in the mentioned two-phase system were calculated; they were found to increase in the following cation order: UO2+ 2 < Zn2+,Ni2+ < Cu2+,Cd2+ < Co2+ < Mg2+ < Ca2+ < Mn2+,Fe2+ < Sr2+ < Pb2+ < Ba2+. © Akadémiai Kiadó, Budapest, Hungary 2010.
Cibulka I.,Institute of Chemical Technology Prague
Journal of Chemical Thermodynamics | Year: 2010
Density values for dilute aqueous solutions of five cyclic ethers (oxolane, 1,3-dioxolane, oxane, 1,4-dioxane, and 1,3,5-trioxane) are presented together with partial molar volumes at infinite dilution calculated from the experimental results. The measurements were performed at temperatures from (298 up to 573) K. Due to thermal decomposition, the upper temperature limit was lower for 1,3-dioxolane (448 K) and 1,3,5-trioxane (498 K). Experimental pressures were close to the saturated vapour pressure of water, and (15 and 30) MPa. The results were obtained using a high-temperature high-pressure flow vibrating-tube densimeter. Experimental standard partial molar volumes were correlated as a function of temperature and pressure using an empirical polynomial function and the semi-theoretical SOCW equation of state. Contributions of the group contribution method proposed previously were also evaluated and analyzed. © 2009 Elsevier Ltd. All rights reserved.
Cibulka R.,Institute of Chemical Technology Prague
European Journal of Organic Chemistry | Year: 2015
Flavinium salts, both isoalloxazinium and alloxazinium derivatives, are useful organocatalysts of redox reactions, and particularly in recent years, the number of transformations catalysed by flavinium salts has increased. This review outlines the synthetic applications of flavinium catalysts in oxygenation reactions with oxygen and hydrogen peroxide as terminal oxidising agents; these oxidations involve flavin hy- droperoxide as an intermediate, thus mimicking flavin monooxygenases. Special attention is paid to mechanistic studies and to the design of catalytic systems, especially the effects of the structures of flavinium catalysts, and reaction conditions on the efficiency, chemoselectivity and stereoselectivity of oxygenations. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Patakova P.,Institute of Chemical Technology Prague
Journal of Industrial Microbiology and Biotechnology | Year: 2013
The genus Monascus, comprising nine species, can reproduce either vegetatively with filaments and conidia or sexually by the formation of ascospores. The most well-known species of genus Monascus, namely, M. purpureus, M. ruber and M. pilosus, are often used for rice fermentation to produce red yeast rice, a special product used either for food coloring or as a food supplement with positive effects on human health. The colored appearance (red, orange or yellow) of Monascus-fermented substrates is produced by a mixture of oligoketide pigments that are synthesized by a combination of polyketide and fatty acid synthases. The major pigments consist of pairs of yellow (ankaflavin and monascin), orange (rubropunctatin and monascorubrin) and red (rubropunctamine and monascorubramine) compounds; however, more than 20 other colored products have recently been isolated from fermented rice or culture media. In addition to pigments, a group of monacolin substances and the mycotoxin citrinin can be produced by Monascus. Various non-specific biological activities (antimicrobial, antitumor, immunomodulative and others) of these pigmented compounds are, at least partly, ascribed to their reaction with amino group-containing compounds, i.e. amino acids, proteins or nucleic acids. Monacolins, in the form of β-hydroxy acids, inhibit hydroxymethylglutaryl- coenzyme A reductase, a key enzyme in cholesterol biosynthesis in animals and humans. © 2012 Society for Industrial Microbiology and Biotechnology.