09 (2003) Scientific papers, Series A
Permanentní URI k tomuto záznamuhttps://hdl.handle.net/10195/38119
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Článek Otevřený přístup peer-reviewedpublished Wall shear stress at the membrane surface and at the surface of plexiglas(Univerzita Pardubice, 2004) Velikovská, Pavlínal|Mikulášek, Petrl|Legentilhomme, Patrickl|Comiti, Jacquesl|Jaouen, PascalThe wall shear stress is determined at the surface of a plane ceramic ultrafiltration membrane and at the plate of Plexiglas in a tangential ultrafiltration module. In a first time, the shear stresses are determined at the surface of a plate of Plexiglas mimicking a membrane and at the plane membrane surface without fouling particles with the aim to investigate the influence of permeation. In the second time, the wall shear stress is determined at the surfaceof the plane membrane during the ultrafiltration of spherical no compressible particles suspension inducting a deposit at the membrane surface. In order to study the influence of the concentration of the particles, two concentrations of particles were used for the experiments. The values of the mean wall shear stress and its fluctuations (turbulent intensity rate) were measured by using an electrochemical method. 20 microelectrodes, on which an electrochemical reaction occurs, are mounted flush to the plate of Plexiglas and to the surface of the membrane to determine the maps of shear stress and turbulent intesity rate for two inlet/outlet distributors' configurations.Článek Otevřený přístup peer-reviewedpublished Modelling the cake filtration on a rotary Nutsche in oscillatory mode(Univerzita Pardubice, 2004) Machač, Ivan; Šiška, Bedřich; Machačová, Ludmila; Doleček, PetrAs an alternative to a classical Nutsche with a flat filtration surface, a rotary Nutsche has been developed. It is constructed like a circular drum with the bottom half being used as the filter area. The drum is placed on wheels and simple rope drive enables the drum to oscillate. During a batch filtration period, the filter area of RN filter decreases and equations of filtration taking into account the variability of filter face area should be used for the prediction of rotary Nutsche filtering performance. Such equations for filtration in the static (non-oscillatory) mode have been presented earlier. Herein, the model modified for filtration in an oscillatory mode is presented and the results of its numerical solution for filtration of diatomite and cellulose suspensions are compared with those obtained in testing the filtering ability of a pilot plant cylindrical rotary Nutsche.Článek Otevřený přístup peer-reviewedpublished Conditions for implementation of logistics into companies of chemical industry in Czech Republic(Univerzita Pardubice, 2004) Vlčková, VladimíraStatus quo in implementation of logistics into companies of chemical industry in the Czech Republic is presented. The reasons that inhibit quicker assertion of logistics into these companies are discussed. Recommendations for a successful implementation of logistic system are given. Unfinished privatization and the therewith related frequent changes in ownership on this branch of industry was identified as the most significant problem.Článek Otevřený přístup peer-reviewedpublished Implementation of environmental management systems in the Czech Republic(Univerzita Pardubice, 2004) Hyršlová, Jaroslava; Böhmová, SimonaThe paper deals with the present situation of the implementation of environmental management systems in the Czech republic. It focuses on the main reasons of EMS implementation in companies, on the costs connected with implementation as well as on the actual economic effects of environmental management systems. The objective of this paper is to point out the present standard of environmental costs tracking in those of Czech companies who have implemented environmental management systems and to stress the importance of such information for company management. The paper includes some of the results acquired from the grant-subsidized project of the Grant Agency of the Czech Republic "Environmental Costs Information for Environmental Management" (No. 402/02/0092).Článek Otevřený přístup peer-reviewedpublished Comparison of methods used for elimination of matrix effect in ICP-AES(Univerzita Pardubice, 2004) Krejčová, Anna; Černohorský, TomášThe determination of Al, Be, Cd, Co, Cr, Cu, Mn, Ni, Pb, V and Zn in high-saline solutions (urine) by ICP-AES method has been studied. The interference due to individual components (NaCl, KCl, CaCO3, MgCl2, NH4H2PO4, HCl, H2SO4 and urea) and their concentration levels were evaluated. Suppression of down to 20% of trace element content was found due to the main inorganic components of urine. The methods for correction of matrix effect, i.e. internal standardisation with Y, Sc and Ar and the "CAIS" technique were tested and and compared with the results of direct determination. The organic components of urine had no significant effect. Two approaches of estimation of LOD were used. The influence of urine matrix on LOD was established. Precision (RSD) was about 1% for internal standardisation and less than 2% for direct estimation. The accuracy was evaluated with urine control materials Seronom Trace Element Urine, batch 403125 (Nycomed Pharma), and Lyhpochek 69012 (Bio-Rad).Článek Otevřený přístup peer-reviewedpublished GC/MS profiling of fatty acids in medically important fungi(Univerzita Pardubice, 2004) Miketová, Petra; Jelínek, David; Khailová, Ludmila; Schram, Karl H.; Moore, Ida M.(Ki); Vytřasová, LudmilaThe application of gas chromatography/mass spectrometry (GC/MS) method was described for the generation of fatty acid profiles of medically important fungi. The composition of fatty acids was characteristic for different fungi and was used for identification and taxonomical purposes. The GC/MS methodology was shown to be suitable for diagnostic pusposes in clinical settings thanks to its sensitivity, speed and accuracy.Článek Otevřený přístup peer-reviewedpublished Determination of extraframework metal content in zeolitic catalysts by means of WD XRF spectrometry(Univerzita Pardubice, 2004) Knotek, Petr; Pouzar, Miloslav; Bulánek, Roman; Novoveská, KateřinaXRF spectroscopy is not widely used for zeolites, but its known advantages are indispensable, i.e. small consumption of the sample (5 mg), analysis of the sample without dissolution, quickly and easy pre-treatment and low-cost analysis. Therefore, development of methodology for determination of metal (Cu, Co, Ga, V) content in zeolites using wavelength dispersive X-ray fluorescence analysis is described in this paper. XRF spectrometer was calibrated for each metal using model pellets containing oxide and boric acid. Response of detector on the amount of metal can be reliably fitted by a linear model. Copper (resp. cobalt) zeolites showed good agreement in metal content determination by XRF and standard validated analysis (AAS and ICP-OES after zeolite dissolution).Článek Otevřený přístup peer-reviewedpublished A study on the applicability of bismuth film plated carbon paste electrodes in highly alkaline media(Univerzita Pardubice, 2004) Elsuccary, Saber A. A.; Švancara, Ivan; Metelka, Radovan; Baldrianová, Lucie; Hassouna, Mohamed E. M.; Vytřas, KarelA silicone oil-based carbon paste electrode plated "in situ" with a bismuth film, BiF(C/SO), has been tested for differential pulse anodic stripping voltammetry of heavy metal ions in highly alkaline media. First, the BiF(C/SO) was examined with respect to its polarisability in solutions of either NaOH or KOH with varying concentration. Further, strpping characteristics of selected metals (Zn, Cd, Pb, and Tl) were investigated in order to define analytical performance of the BiF(C/SO) in 0.1 M KOH chosen as optimal medium. The study has revealed some specifics of measurements in solutions with high pH due to complex-forming capabilities of the OH- ions, contributing thus to the continuing characterisation of bismuth film-based electrodes.Článek Otevřený přístup peer-reviewedpublished New energetic materials of N-heterocyclic group(Univerzita Pardubice, 2004) Jalový, Zdeněk; Vávra, PavelPotential candidates for highly efficient and, at the same time, insensitive energetic materials have been analysed. The group analysed comprises N-heterocyclic compounds, pyridines, pyrazines, pyrimidines, tetrazines, triazoles, pyrazoles and compounds containing a furazane or furoxane unit. Density, heat of formation, and melting point have been chosen for the comparison parameters.Článek Otevřený přístup peer-reviewedpublished Influence of road salting materials on vegetation close to roads(Univerzita Pardubice, 2004) Bajer, Tomáš; Brunclík, Tomáš; Sákra, Tomáš; Chýlková, Jaromíra; Poláčková, DanaThis paper deals with the investigation of impact of road salting materials (deicing salts) to vegetation close to roads. Extensive survey of the present knowledge is submitted in the first part. In the experimental part concentrations of undesirable contaminants in the salting materials and chloride ions in the soil samples have bean partcularly observed. Amounts of heavy metals and other contaminants were very low on the roadsides, concentration pf chlorides rapidly decreased upright to the road.