08 (2002) Scientific papers, Series A
Permanentní URI k tomuto záznamuhttps://hdl.handle.net/10195/38118
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Článek Otevřený přístup peer-reviewedpublished Comparison of mathematical models for tray distillation column(Univerzita Pardubice, 2003) Honc, DanielPresented paper deals with mathematical models of a pilot-plant bubble-cup tray distillation column. Two universal models have been derived by the mathematical-physical analysis. Two versions of models have been considered in the simple transfer function form. Step responses and responses to more complex input signals have been measured. Values of models unknown parameters have been estimated from experimental data by the numerical optimisation. The models are verified for more complex input signal and the closed loop.Článek Otevřený přístup peer-reviewedpublished Electrochemical biosensors; a promising tool in chemical analysis(Univerzita Pardubice, 2003) Girousi, StellaThe scope of the present article is to provide some useful information to new beginners in the field of electrochemical biosensors. A biosensors exploits biological or biochemical mechanisms in the recognition and the analysis of certain chemical compounds. Analytical advantages are specificity, sensitivity and cheap instrumentation. Regarding the analytical accuracy, they are proper in the development and application of screening methods of analysis. This article presents a short bibliographic survey of the applications of biosensors in environmental, drug and food analysis.Článek Otevřený přístup peer-reviewedpublished Creeping motion of a single fluid and solid sphere in non-Newtonian fluids(Univerzita Pardubice, 2003) Dolejš, Václavl|Šiška, Bedřichl|Teichman, Romanl|Doleček, PetrAn approach to the calculation of drag and velocity of a single Newtonian fluid sphere moving slowly in generalized Newtonian and viscoplastic fluids is suggested. It is based on the application of the modified Rabinowitsch-Mooney equation together with the corresponding relations for consistency variables, which have been suggested for the creeping motion of the solid sphere, and on the application of the relationship of Hadamard-Rybczynski valid for both fluid and solid spheres. The solution is concretized for the power-law, Ellis, Bingham, and Robertson-Stiff flow models.Článek Otevřený přístup peer-reviewedpublished Deficiencies of the existing systems of managerial accounting for the needs of environmentally-oriented management and their prospects(Univerzita Pardubice, 2003) Hyršlová, JaroslavaThis paper deals with the deficiencies of the existing systems of managerial accounting and their prospects as an informative tool for environmentally-oriented management. The existing systems of managerial accounting trace, monitor, and evaluate environmental costs in an inadequate manner and do not provide sufficient information for environmentally-oriented management. Only by connecting information concenrning environmental costs with information arising from material and energy balances shalt it be possible to obtain the information required for the resolution of decision-making tasks within the scope of environmentally-oriented management, and to design and implement such measures that would lead to an improvement in economic results and to reduction of the impacts on the environment of the activities, products, and services of enterprises.Článek Otevřený přístup peer-reviewedpublished Hydrodynamic based calculation of steady state permeate flux in microfiltration process(Univerzita Pardubice, 2003) Pospíšil, Petr; Mikulášek, Petr; Doleček, PetrCrossflow microfiltration experiments were performed with aqueous titanium dioxide dispersions and alumina tubular membranes. Intensification effect of twophase gas-liquid flow was studied on this system. The results of experiments show a positive effect of constant gas-liquid two-phase flow on the permeate flux values; both the immediate and steady state ones. The maximum increase in flux values up to 90% was reached during the experiments in the slug flow regime of gas-liquid flow, which was found the most efficient regime applied during intensification experiments. The empirical model for steady state permeate flux and cake thickness prediction was developed from analysis of experimental results without gas flow. this model is based on Darcy's Law and on Mass balance over a membrane module. Dimensionless numbers covering all the basic operating conditions that influence permeate flux and cake thickness were introduced, and from their regression in the range of experimental feed concentrations final equations were derived. The results show good agreement between model prediction and experimental data with gas-liquid flow tested on the same apparatus.Článek Otevřený přístup peer-reviewedpublished Calculation of dot area with image analysis method(Univerzita Pardubice, 2003) Fribert, MiroslavImage analysis is a suitable method to calculate the basic print characteristic from print samples, because of the possibility of scanning geometrical and colour characteristic at the same time. This paper deals with the calculation of the dot segmentation of halftone dots from the print sample must be done. The paper describes an algorithm of dot area calculation based on the segmentation and presents the results obtained with processing one-colour and two-colour print samples. Finally the resuts of the image analysismethod and densitometric method are compared.Článek Otevřený přístup peer-reviewedpublished Application of pressurised fluid extraction to sample preparation(Univerzita Pardubice, 2003) Adam, Martin; Ventura, Karel; Eisner, AlešThe article is focused on the pressurised fluid extraction - PFE technique using of a one PSE device and its application to isolation of various organic compounds from solid samples. In this paper optimisation procedure for individual analytes is described and discussed. Applicability of PFE is tested on isolation procedures of phthalates, PAHs and TPHs from environmental materials (soils, river sediments), and the additives in smokeless gunpowders.Článek Otevřený přístup peer-reviewedpublished Application of supercritical fluid extraction to isolation of additives from smokeless gunpowders(Univerzita Pardubice, 2003) Eisner, Aleš; Ventura, Karel; Adam, MartinThis paper deals with the application of supercritical extraction to isolation of additives from samples of smokeless powders, as an to classical fluid extractions (using Soxhlet apparatus or ultrasonication). The reasons for introduction of new extraction techniques are the decrease in volume of the solvents used for extraction and shortening the time of extraction, which usually takes several hours or even days. In the supercritical fluid extraction it is necessary to optimize the basic extraction parameters (temperature, pressure, modifier, treatment of the sample by means of grinding and the lenght of static step).Článek Otevřený přístup peer-reviewedpublished Amperometric determination of sarcosine with sarcosine oxidase entrapped with Nafion on manganese dioxide-modified screen-printed electrodes(Univerzita Pardubice, 2003) Kotzian, Petrl|Beyene, Negussie W.l|Llano, Laura F.l|Moderegger, Helmutl|Tuñón-Blanco, Paulinol|A simple biosensor, constructed by bulk-modification of carbon ink with manganese dioxide as an electron mediator and sarcosine oxidase enzyme as a biocomponent entrapped with Nafion was developed and investigated for its ability to serve as amperometric detector of sarcosine in flow injection analysis (FIA) mode. The dependence of the response on the applied potential, the pH of phosphate buffer, the concentration and the flow rate were studied. Factors influecing the amperometric response were studied in detail. The sensors could be operated at optimized conditions which were found as follow: flow rate, 0.2 ml min-1; carrier, 0.1 M phosphate buffer (pH 8.25); injection volume, 150 ul; operation potential, 0.38 V vs. Ag/AgCl. The sensor exhibited a linear increase of amperometric signal with the concentration of sarcosine in the range of 10-250 ppm (R2=0.9992) with a detection limit (evaluated as 3o) of 2.5 mg l-1. The developed biosensors exhibited a good selectivity over other biogenic amines. Its application in food analysis was also examined.Článek Otevřený přístup peer-reviewedpublished Determination of phospholipids as biomarkers of brain tissue damage in acute lymphoblastic leukemia patients(Univerzita Pardubice, 2003) Miketová, Petral|Moore, Ida M. (Ki)l|Pasvogel, Alicel|Khailová, Ludmilal|Schram, Karl H.l|Hutter, John J.l|Kaemingk, Kristine L.The application of a high performance liquid chromatography method was described for determination of phospholipid levels in the cerebrospinal fluid of children suffering with acute lymphoblastic leukemia (ALL). The levels of two major membrane phospholipids (phosphatidycholine and sphingomyelin) were monitored during the course of therapy and compared among three different therapeutic protocols. The monitored levels were correlated with the results of cognitive testing and assessed as biomarkers of cellular damage associated with ALL treatment.