National Repository of Grey Literature 86 records found  beginprevious55 - 64nextend  jump to record: Search took 0.01 seconds. 
Analysis of the degradation products of the active substances in historical pharmaceutical relicts from 18th and 20th century.
Čambal, Peter ; Nesměrák, Karel (advisor) ; Kubíčková, Anna (referee)
Historical pharmaceutical preparations analyzed in this thesis were a senna extract more than 200 years old, an ointment "Naso-Merfen" 75 years old, and an ointment "Sulfathiazol" 42 years old. The active substances in the analyzed samples were sennosides A and B (senna extract), ephedrine and menthol (the ointment "Naso-Merfen"), and sulfathiazole (the ointment "Sulfathiazol"). The senna extract was analyzed by RP-HPLC and HPLC-MS. Separation conditions were optimized, especially for separation of the sennoside A and B enantiomers. The active substances were not detected in the sample. One degradation product and substances characteristic for senna were identified. Their presence in the historical and contemporary sample was compared. Detailed ESI− -MSn fragmentation mechanisms of sennoside A and B have been proposed. The sample of the ointment "Naso-Merfen" was analyzed by HILIC-UV, HPLC-MS, GC-MS, and AAS. Separation conditions were optimized. The active substances were quantified. Degradation products of the active substances were not detected in the sample. The sample of the ointment "Sulfathiazol" was analyzed by RP-HPLC and HPLC-MS. Separation conditions were optimized. The active substance was quantified. Degradation products of the active substance were not detected. The authenticity of...
Speciation analysis of arsenic and mercury using postcolumn generation of their volatile compounds for needs of atomic spectroscopic methods
Linhart, Ondřej
The presented dissertation thesis deals with the use of UV-photochemical generation of volatile compounds (UV-PVG) as a derivatization technique for the combination of high-performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) detection. Two model elements arsenic and mercury and their compounds were selected for the speciation analysis. The work was divided into several parts that follow. In the first part of the research, the apparatus for the UV-photochemical generation of the volatile mercury compounds and their detection with a new continuum source and high-resolution atomic absorption spectrometer (HR-CS AAS) with an externally heated detection tube was constructed. The analytical method was adapted for use with atomic fluorescence detection with the aim to improve sensitivity of the determination. Furthermore, apparatus for the electrochemical generation of cold mercury vapor with AAS detection was built. The construction of the apparatus was followed by optimization of the reaction conditions (concentration and flow of electrochemical reagents: sulfuric and hydrochloric acid, mobile phase, carrier medium, flow rate of the carrier gas and localization of its introduction), determination of the analytical figures of merit, and comparation of the methods. Both...
Hydride generation study for arsenic speciation analysis with AAS and AFS detection
Svoboda, Milan
The general aim of this work was a development of methodology and instrumentation for speciation analysis based on the combination of the selective generation of substituted hydrides with atomic absorption or atomic fluorescence spectrometry detection. The first topic of this work was the development of methodology and instrumentation for arsenic speciation analysis based on selective generation of substituted arsines with trapping in the cryogenic trap (U-tube packed with chromosorb) with AAS detection (HG- CT-AAS). The conditions of the selective hydride generation approach as well as working procedure of the cryogenic trap were optimized (appropriate approach for hydride generation, set up of heating program of cryogenic trap, new dryer - cartidge with NaOH, elimination of unspecific absorption, decreasing of the detection limits). The second important part of the work lay in applying of the developed method for arsenic speciation analysis in a homogenized mouse liver tissue. The direct slurry sampling to hydride generator was develop. Moreover the information about oxidation state (iAsIII,V , MAsIII,V a DMAsIII,V ) was obtain. The effect of relevant experimental parameters such as tetrahydroborate concentration, TRIS buffer concentration and time of pre-reduction of the samples by L-cysteine...
Inorganic analysis of microwave pyrolysis products from sewage sludge
Šintajová, Kristína ; Doležalová Weissmannová, Helena (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the analysis of risk elements found in the sewage sludge of wastewater treatment plants and the issue of contamination caused by sludge deposition in soils. Extractions of sewage sludge samples before and after pyrolysis treatment were implemented according to the sequential extraction of BCR and also using aqueous leaching. The determination of the selected element was performed on an atomic absorption spectrometer. A literature research on the use of modified sewage sludge after pyrolysis to increase fertility, improve soil properties and improve their quality was also processed.
Communication Interface for Industry 4.0 testbed
Magáth, Marek ; Fiedler, Petr (referee) ; Kaczmarczyk, Václav (advisor)
This diploma thesis deals with the creation of a general communication interface between the smart product and process cells within test bed Barman. The aim is to create distributed production according to the Industry 4.0 concept, where each product manages it’s production itself. The first part deals with the analysis of test bed, where are discussed requirements and method of production. Then with the selection of a communication protocol that would meet Industry 4.0 and distributed control requirements. The result of the research was OPC UA communication protocol. Using this protocol, the product and the process cell will communicate with each other. I chose the appropriate implementation for the selected protocol to be used for creating communication modules of the product and the process cell. Production data will be stored in an RFID chip located in the product. Part of the work is devoted to creation this data structure, which contains the recipe as well as production state data. Creation of RFID reader is the work of another student, with whom I solved the method of data exchange between application of the reader and the communication module of the product. When creating a communication module of the process cell, I solved the design of an information model that describes the entire process cell, and the dynamic creation of nodes in the address space. I have mentioned a few examples of how I worked with a selected implementation of OPC UA and how I used it in both applications. I implemented decentralized search of another process cells in the local network. This feature was easy to implement with OPC UA, specifically with the LDS-ME service. I solved the control of production for the communication module of the product and method of communication with the process cell. And in the last part I deal with manual, which describes how to compile projects correctly, specifically on the Linux operating system, and I have described a way to test the whole solution together with the results.
Effect of metal sensitizers on photochemical vapor generation of bismuth for analytical atomic spectrometry
Vyhnanovský, Jaromír ; Yildiz, D. ; Musil, Stanislav
Three new sensitizers with a significant positive effect on the photochemical vapor generation of bismuth were described. Cobalt was found to be the most effective and led to a significant enhancement of the signal.
Speciation analysis of arsenic and mercury using postcolumn generation of their volatile compounds for needs of atomic spectroscopic methods
Linhart, Ondřej
The presented dissertation thesis deals with the use of UV-photochemical generation of volatile compounds (UV-PVG) as a derivatization technique for the combination of high-performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) detection. Two model elements arsenic and mercury and their compounds were selected for the speciation analysis. The work was divided into several parts that follow. In the first part of the research, the apparatus for the UV-photochemical generation of the volatile mercury compounds and their detection with a new continuum source and high-resolution atomic absorption spectrometer (HR-CS AAS) with an externally heated detection tube was constructed. The analytical method was adapted for use with atomic fluorescence detection with the aim to improve sensitivity of the determination. Furthermore, apparatus for the electrochemical generation of cold mercury vapor with AAS detection was built. The construction of the apparatus was followed by optimization of the reaction conditions (concentration and flow of electrochemical reagents: sulfuric and hydrochloric acid, mobile phase, carrier medium, flow rate of the carrier gas and localization of its introduction), determination of the analytical figures of merit, and comparation of the methods. Both...
The content of selected group 1 and 2 metals in edible mushrooms
MÁCHOVÁ, Nikola
Edible mushrooms are able to accumulate elements, especially some heavy metals and radionuclides, in their fruiting body. This work engages in accumulation of chosen metals (Groups 1 and 2) in basidiomycete fungi and soil. The first picking happened in autumn 2017. Eleven mushroom specimens were found - several fruiting bodies of each type. The soil where the mushrooms had grown was also taken. During the other picking in autumn 2018 ten types of mushrooms were taken. The locality in the Czech Republic (Ledenice) was chosen, because these fungi were frequently found there: Agaricus campestris, Boletus edulis, Suillus variegatus, Xerocomellus chrysenteron, Neoboletus luridiformis, Leccinum rufum, Macrolepiota procera, Suillus luteus, Imleria badia, Leccinum scabrum, Lactarius deliciosus, Agaricus silvaticus, Suillus bovinus and Amanita rubescens. The chosen metals were Lithium (Li), Strontium (Sr), Cesium (Cs) and Rubidium (Rb). I used methods of atomic absorption spectrometry (AAS). In both analysis (2017 and 2018) the largest content of Lithium was recorded in Agaricus campestris fruiting body (2.3 mg/kg and 1.6 mg/kg) and the largest content of Strontium in Leccinum rufum (3.7 mg/kg and 6.6 mg/kg). It was shown that varieties of the Bolete family demonstrated the biggest accumulation of Rubidium (Boletus edulis 519 mg/kg, Neoboletus luridiformis 398.6 mg/kg). The biggest content of Cesium (about 1.1 mg/kg) was recorded also in this family.
Speciation analysis of arsenic and mercury using postcolumn generation of their volatile compounds for needs of atomic spectroscopic methods
Linhart, Ondřej ; Červený, Václav (advisor) ; Spěváčková, Věra (referee) ; Šíma, Jan (referee)
The presented dissertation thesis deals with the use of UV-photochemical generation of volatile compounds (UV-PVG) as a derivatization technique for the combination of high-performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) detection. Two model elements arsenic and mercury and their compounds were selected for the speciation analysis. The work was divided into several parts that follow. In the first part of the research, the apparatus for the UV-photochemical generation of the volatile mercury compounds and their detection with a new continuum source and high-resolution atomic absorption spectrometer (HR-CS AAS) with an externally heated detection tube was constructed. The analytical method was adapted for use with atomic fluorescence detection with the aim to improve sensitivity of the determination. Furthermore, apparatus for the electrochemical generation of cold mercury vapor with AAS detection was built. The construction of the apparatus was followed by optimization of the reaction conditions (concentration and flow of electrochemical reagents: sulfuric and hydrochloric acid, mobile phase, carrier medium, flow rate of the carrier gas and localization of its introduction), determination of the analytical figures of merit, and comparation of the methods. Both...
Generation of volatile species of palladium for atomic absorption spectrometry
Vyhnanovský, Jaromír ; Musil, Stanislav (advisor) ; Matoušek, Tomáš (referee)
This thesis deals with optimization of the conditions for chemical generation of volatile species of palladium in combination with atomic absorption spectrometry. The volatile species of palladium were generated in a flow injection system by the reaction of an acidified sample with the solution of sodium borohydride in the presence of reaction modifiers. A diffusion flame atomizer was used due to its high robustness. In the first part of this thesis the optimization of parameters affecting the atomization in the diffusion flame was carried out (flow rates and composition of gases, observation height). In the second part, concentrations of individual reagents used (nitric acid, sodium borohydride, Triton X-100, Antifoam B, sodium diethyldithiocarbamate) were optimized. The positive effect of the reaction modifiers was demonstrated, especially that of sodium diethyldithiocarbamate, which lead to a tenfold increase in the sensitivity. The limits of detection and limits of quantification for the wavelength 244,8 nm were 0,25 mg dm-3 and 0,67 mg dm-3, respectively. The repeatability for this method for the concentration 5 mg dm-3 was 2,8 %. Key words: palladium, chemical generation of volatile species, atomic absorption spectrometry

National Repository of Grey Literature : 86 records found   beginprevious55 - 64nextend  jump to record:
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