16 (2010) Scientific papers, Series A
Permanentní URI k tomuto záznamuhttps://hdl.handle.net/10195/42480
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Článek Otevřený přístup peer-reviewedpublished New type of PVC-membrane Ion-selective electrodes and their applicability to determine some antidepressand drugs(Univerzita Pardubice, 2010) Wassel, Anwar A.; Abdullatif, ShabaanThe construction and electrochemical characterisation of potentiometric sensors of the PVC-membrane type are described being developed for the determination of selected antidepressants; namely: Olanzapine, Oxazepam, and Lorazepam. The sensing PVC-membranes incorporate the ion-associates of the drug cations with ammonium reineckate as selective materials dispersed in 2-nitrophenyl-octylether (NPOE) or dibutyl sebacate (DBS) as the plasticizers of choice. These ISEs exhibit rapid, stable and nearly Nernstian response over a relatively wide concentration range of 1×10–7 mol l–1-0.01 mol l–1 for Olanzapine and 1×10–6-0.01 mol l–1 for Oxazepam and Lorazepam, in mild acidic solutions with pH 4.5. No interferences caused by either inorganic or organic species were found. The three electrodes developed have been tested for potentiometric titrations of all three drugs, as well as for their direct determination via the respective calibration curves. The individual experiments then resulted in average recovery rates in an interval of 34 Wassel A.A., Abdullatif S./Sci. Pap. Univ. Pardubice Ser. A 16 (2010) 33–55 98.4-99.2 %, with the R.S.D. of ca. ±1.5 % (n = 3) for all three analytes of interest. Finally, the method proposed has been applied to the determination of the three drugs in pharmaceutical formulations and urine, when the results obtained were comparable to those obtained with the reference HPLC measurements.Článek Otevřený přístup peer-reviewedpublished Triple helix model in the Czech tertiary education(Univerzita Pardubice, 2010) Sabolová, VeronikaThe article is devoted to the issue of triple helix model and its application in the Czech tertiary education. Introduction describes the crucial provisions of the White Paper on Tertiary Education. Then the triple helix model is described based on the foreign literature search. Particular attention is focused on the importance of the triple helix model in the White Paper on Tertiary Education. Finally, possible subjects of the cooperation between university, industry and government are indicated.Článek Otevřený přístup peer-reviewedpublished Time series forecasting as a tool of operative management(Univerzita Pardubice, 2010) Paták, Michal; Vlčková, VladimíraPresent quickly varying business environment requires changes in traditional logistic management of companies of chemical and food industry operating on B2C markets. Usage of recent logistic technologies however is made impossible due to the position of Czech companies on the markets mentioned. This article presents the problems which these companies solve on the operative level, and points out possibilities of time series analysis utilization as a tool of demand planning. Possible application of this tool in operative management and its incidences are described on a chosen company of food industry.Článek Otevřený přístup peer-reviewedpublished Anticorrosion properties of ion-exchangable pigments in epoxide coatings(Univerzita Pardubice, 2010) Obrdlík, Štěpán; Kalendová, Andrea; Matějková, EvaHexavalent chromium compounds (chromates) have been widely used as inhibitive pigments in the formulation of anticorrosive paints. However, their high toxicity and carcinogenic effects are forcing the development of effective chromate-free organic coatings. One such alternative, which is very attractive from a scientific point of view, is the use of ion-exchangeable pigments (IEPs). The few studies conducted with this type of pigment are not conclusive about their anticorrosive efficiency and controversy surrounds their functioning mechanisms, interchange capacity and anticorrosive performance. In the present research, which focuses on the anticorrosive protection of this type of pigment, calcium/silica (Ca/Si) IEPs were synthesized in first step, next epoxide paint coatings were formulated. IEPs have been applied on low carbon steel panels. The effect of these non-toxic pigments on the protective properties of coatings has been tested by means of natural and accelerated corrosion tests (humidity, salt spray and SO2). Experimental results have shown that IEPs are suitable to formulate anticorrosive paint films with improved anticorrosive effects.Článek Otevřený přístup peer-reviewedpublished Preparation of surface modified kaolines by silicone hydrophobization(Univerzita Pardubice, 2010) Matějková, Eva; Kalendová, Andréa; Obrdlík, ŠtěpánThis work deals with preparation of silanized kaolines for application in organic coatings. Coatings have a crucial task in protection of metal materials against rust. Leafy fillers improve anticorrosive properties (they participate in barrier mechanism), stability in atmospheric influences and adhesion to base plate. Organic silicate substances are able to create hydrophobic layer on a surface of different materials. Hydrophobization reduces a possibility of osmotic blisters creation. Four samples were prepared from four types of silanes (polydimethylsiloxane, methyltrimetoxysilane, aminoalkyl siloxane and aminopropylsilane) and two different kaolines. The following samples were prepared: A- Al6Si2O13 (mullite, S1),B- SiO2 (quartz, S2),C- Al6Si2O13 (mullite,S3),D- SiO2 (quartz, S4). Properties which are important for application in coatings were astimated by means of the following tests: structure identification by X-ray diffraction analysis, determination of the specific mass, oil consumption determination, specific surface area determination, determination of particle size and distribution, determination of the morphology of particles. Determination of methanol (MN) and water (WN) number is very important for evaluating anticorrosion properties of silanized samples in coatings. The prepared pigments have diverse chemical composition and content of structural phase quartz and mullite. The characterization of pigments shows good properties of tested pigments for production of coatings. Mechanical and anticorrosive properties will be investigated.Článek Otevřený přístup peer-reviewedpublished Use of new reactive dyes for dyeing of polyamide 6 and wool(Univerzita Pardubice, 2010) Lišková, Vlasta; Pinto, Tiago A. D.; Burgert, Ladislav; Hrdina, RadimThis paper describes the research of newly designed and prepared reactive dyes for dyeing of polyamide 6 and wool. For this purpose, disazo reactive dyes with sulfatoethylsulfonyl group have been synthetized by the sequence of diazotation of aromatic amines and coupling reactions of formed diazonium compounds with secondary components (1-naftylaminesulfonic acids). In order to increase some colouristic properties of reactive dyes, such as fixation, exhaustion and wet fastness, the reactive group of the dyes was modified with sarcosine in several cases to form N-methyl-N-carboxymethyl-2-aminoethylsulfonyl group. In addition, dichloro-triazine dyes in modified and unmodified form have been tested as well. It was find out that the modification of reactive group with sarcosine improved significantly the colouristic properties of some reactive dyes applied to both 112 Lišková V. et al./Sci. Pap. Univ. Pardubice Ser. A 16 (2010) 111–132 investigated textile materials. Nevertheless, this method was not found to be universal for all the types of investigated reactive dyes. What can further be seen from the presented results is that among all the of investigated dyes some have been found to show especially high values of fixation that can overcome very frequent and common problems of low fixation occurring during the application of reactive dyes to dying of polyamide.Článek Otevřený přístup peer-reviewedpublished Simultaneous determination of vanillylmandelic and homovanillic acids in urine using LC with coulometric electrochemical detection based on SPE sample preparation(Univerzita Pardubice, 2010) Kanďár, Roman; Žáková, PavlaThe aim of the study was to develop a simple and selective LC method for the simultaneous measurement of vanillylmandelic acid (VMA) and homovanillic acid(HVA) in human urine. A method for the measurement of VMA and HVA using LC with coulometric electrochemical detection and investigation into the extraction techniques with regard to stability and recovery are described. The analytical performance of presented method is satisfactory. The presented method uses a relatively rapid SPE procedure. It can be used both for research and for clinical testing purposes.Článek Otevřený přístup peer-reviewedpublished Determination of coproporphyrin I and III in human urine using HPLC with fluorescence detection(Univerzita Pardubice, 2010) Kanďár, Roman; Žáková, Pavla; Frölichová, Martina; Štramová, Xenie; Bencová, SoňaThe determination of selected porphyrins, especially of coproporphyrin I and III is presently the most reliable direct approach to the screening of porphyrias. An HPLC method for the simultaneous measurement of coproporphyrin I and III in urine samples has been developed and evaluated. Separation of coproporphyrin I and III from interfering substances was achieved on reversed phase HPLC with gradient elution and fluorescence detection. Analytical performance of this method is satisfactory for both coproporphyrin I and coproporphyrin III: the intra-assay and inter-assay coefficients of variation were below 10 %. Quantitative recoveries from spiked urine were between 85.0 and 101.1 %. The limit of detection was 3.0 and 2.3 :g l–1, respectively. The preliminary reference ranges of coproporphyrin I and III in a group of donors are 5.0-51.6 :g l–1 88 Kanďár R. et al./Sci. Pap. Univ. Pardubice Ser. A 16 (2010) 87–98(0.59-3.20 :g mmol–1 creatinine) and 14.9-65.4 :g L-1 (0.98-8.21 :g mmol–1 creatinine). The presented method is inexpensive and suitable for screening of porphyrias.Článek Otevřený přístup peer-reviewedpublished Optical properties of Tl-doped Bi2Se3 single crystals(Univerzita Pardubice, 2010) Janíček, Petr; Drašar, Čestmír; Krejčová, Anna; Lošťák, Petr; Navrátil, JiříBi2–xTlxSe3 single crystals with the Tl content of cTl = 0 to 5.2×1024 atoms m–3 prepared from the elements of 5N purity by means of a modified Bridgman method were characterized by the measurements of infrared reflectance and transmittance. The values of the plasma resonance frequency Tp, optical relaxation time J, and high-frequency permittivity g4 were determined by fitting the reflectance spectra using plasma-resonance formula. It was found that the substitution of Tl atoms for Bi atoms in the Bi2Se3 crystal lattice leads to a decrease in the wp values implying a decrease in the free carrier concentration. This effect is explained within a model of the point defects in the crystal lattice of Bi2–xTlxSe3. The dependences of the absorption coefficient K on the energy of incident photons were determined from the transmittance spectra. The optical 76 Janíček P. et al./Sci. Pap. Univ. Pardubice Ser. A 16 (2010) 75–85 width of the energy gap decreases with the increasing Tl content. The values of the exponent $ from the relation of K ~ 8$ for the long-wavelength absorption edge range within the interval from 2.1 to 2.5 indicating the dominant scattering mechanism of free current carriers is the scattering on acoustic phonons.Článek Otevřený přístup peer-reviewedpublished Contamination of atmosphere with volatile hydrocarbons during handling oil products of petrol and diesel fuel types(Univerzita Pardubice, 2010) Chýlková, Jaromíra; Šelešovská, Renáta; Stuchlík, Martin; Machalíková, JaroslavaThe paper describes monitoring of contamination of atmosphere with organic substances during ordinary operation of a petrol station, namely during pumping of fuel by a consumer. The measurements were performed by means of a portable analyser ECOPROBE 5 equipped with an IR detector. The analyser was calibrated using standard mixtures of petrol vapours and air as well as by means of gaseous standards of volatile portions of Diesel fuel. The calibration curves obtained were used for determination of real concentrations of the analysed substances in the units of mg m–3. The practical measurements have shown that the reverse exhaust of petrol vapours cannot prevent contamination of the atmosphere unless the dispensing nozzle is properly inserted during filling the tank.