National Repository of Grey Literature 47 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
Determination of selected metals in soils and mushrooms in the vicinity of the D1 highway.
The aim of the bachelor thesis was to determine the concentrations of heavy metals in edible mushroom samples and underlying soils. The elements measured were mainly copper, iron and zinc, followed by manganese, strontium and rubidium. The literature search contains brief information on each element and their content in soils and fruiting bodies of mushrooms in other studies. The theoretical part also includes chapters on fungi, soils and their contamination, the effect of vehicular traffic on the heavy metal content of soils and the used analytical method, which was atomic absorption spectrometry. For the practical part, 24 samples of eight different species of edible mushrooms were collected in the autumn of 2020 and 2021 in the vicinity of the D1 motorway. As part of the collection, the soil beneath the mushroom was also sampled to a depth of approximately 15 cm. The samples were first perfectly dried, then processed by microwave digestion, and finally analysed by AAS. All work was carried out in the laboratories of the Department of Applied Chemistry, Faculty of Agriculture and Technology, University of South Bohemia in České Budějovice. The results of the measurements were tabulated and processed statistically and graphically. Finally, they were evaluated in a discussion. The analysis showed that birch and birch goosefoot accumulate the least heavy metals in their fruiting bodies. The spruce budworm, the pink toadflax, the celandine and the brown mushroom accumulate metals on a large scale. In total, 4.2-45 dry weight Cu, 97,4-4166 Fe, 52,1-338,7 Zn, 3-61,4 Mn, 1,3-7 Sr and 7,7-300,9 Rb were measured in mushrooms. In soils, the values were as follows: 5,2-78,6 Cu, 2 965-41 983 Fe, 25,8- 174,2 Zn, 49,7-1 868 Mn, 6,2-25,2 Sr and 12,2-114,5 Rb in dry weight. These results show that strontium was the least represented heavy metal studied and iron was the most represented.
Asset Administration Shell for the operator
Houdek, Vojtěch ; Kaczmarczyk, Václav (referee) ; Baštán, Ondřej (advisor)
This bachelor thesis deals with the topic of AAS (asset administration shell), an element of industry 4.0. The first half of the work consists of a theoretical analysis of the concept of AAS and its active and passive parts. The second half is devoted to the practical design and implementation of AAS for the operator. The implementation of the communication architecture and the selection of suitable Hardware for AAS are addressed here. The resulting implementation deals with programming the active and passive part of AAS in C/C ++ and mobile applications in Android Studio using the programming language Kotlin
Demonstrative manufacturing system controlled by MES utilizing AAS
Černocký, Petr ; Kaczmarczyk, Václav (referee) ; Arm, Jakub (advisor)
This work examines today's modern possibilities for production management. More specifically, we focus on MES and its integration within the concept of industry 4.0 using AAS. Furthermore, a search of available open-source MES systems and their description is performed. After their commissioning, their suitability for further use is discussed. There is also an analysis of tools for creating virtual models. The IMES application, which was subsequently slightly modified, and the RobotStudio virtual model creation tool are then selected from these analyzes. This application and tool are then used to implement virtual line control using a separate MES and to basic control using AAS.
Determination of the risk elements and other elements concentration in animal feed
Křehlíková, Jana ; Juglová, Zuzana (referee) ; Diviš, Pavel (advisor)
This thesis deals with the determination of selected microelements and macroelements and risk elements in dog and cat food. The theoretical part describes the nutrition of dogs and cats and focuses on the safety of the food in the context of contamination with risk elements. Another topic discussed is the chemical analysis of feeds, specifically the determination of nutritionally important substances, beneficial elements, and contaminants. The experimental part deals with the preparation and digestion of feed samples and the subsequent analysis of these samples using ICP-OES and AAS methods. The detected concentrations of the elements of interest in the feeds were compared with the feed standards issued by the Department of Veterinary Medicine and the decree issued by the Ministry of Agriculture. The analysed feeds were found to be deficient in some elements. The content of the risk elements in the feed met the legal limits and did not pose a health risk to the animal. Elements for which the legislation does not provide a maximum permissible limit were present in the feed-in in high concentrations that could already harm the animal's health.
Asset Administration Shell for PLC
Maslowski, Jakub ; Arm, Jakub (referee) ; Benešl, Tomáš (advisor)
This bachelor work gradually summarizes the findings regarding I4.0, as well as its basic parts (AAS, RAMI and DT). Subsequently, it focuses on the description of AAS with regard to the necessary compromises from its original idea with the aim of its successful implementation in PLC, which represents some limitations. The work includes solutions of suitable communication protocols for AAS in PLC. The practical part focuses on the implementation of AAS in PLC from Siemens S7-1200 series using OPC UA methods. SiOME and UaExpert programs are used in the creation. The thesis contains detailed instructions for replication of AAS implementation together with suggestions for possible improvements and its benefits in practise.
Study of the content of risk elements in soils and plant material
Vlčková, Renáta ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the study of the content of selected heavy metals (Zn, Ni, Fe, Mn) in soils and mushrooms. The flame atomic absorption spectrometry method was used to determine the heavy metal content. Fungi and soil samples were collected at 18 sites in the Jeseníky region. The concentrations of heavy metals in the mushrooms were in the range from 140–582 mg/kg Zn, 48–380 mg/kg Fe, 5–19 mg/kg Mn and 3–8 mg/kg Ni. Zinc had the highest concentration value in all mushroom species. In soils, the concentrations of heavy metals ranged from 10–72 g/kg Fe, 52–1,000 mg/kg Mn, 29–115 mg/kg Zn and 6–50 mg/kg Ni. Iron was the most abundant element in the soils. Mushrooms contamination was assessed as a health risk in the study area. However, the pollution of forest soils was assessed as satisfactory and thus the productive function of the soil is not impaired. The type of forest cover was found to have minimal effect on the chemical composition of the soils.
Study of surface water quality in the Ivančice area
Jonášová, Simona ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
Selected physical and chemical water quality parameters were measured at four sampling localities on the Jihlava River. Using UV-VIS spectrophotometry, inorganic forms of nitrogen, chlorides, total phosphorus and CODCr were determined. BOD5 was determined by the dilution method. Na+, K+ and Ca2+ ions, whose concentrations ranged from 5,75–108 mgl 1, were measured by flame emission photometry. Selected metals (Cu, Ni, Pb, Zn, Hg, Cr, Fe, Mn) were determined in water by the ET-AAS method. Decomposed sediments were determined by the FAAS method. Concentrations of Cr, Cu, Pb and Ni in water were in the range of 0,05–2,84 gl1. Metal concentrations in sediments ranged from 0,02–293 mgkg1, where nickel concentrations were above the limit. The occurrence of iron and manganese is due to the geological subsoil. For the other elements, anthropogenic source is assumed. From the measured data, the water quality is slightly variable in this locality and is classified as fourth or fifth class, i.e. as highly polluted water.
UV-Photochemical Generation of Volatile Compounds for Determination of Se in Selected Nutrition Supplemets
Kolorosová, Alžběta ; Červený, Václav (advisor) ; Kratzer, Jan (referee)
The option of UV-photochemical generation of volatile compounds coupled with atomic absorption spectrometry for the determination of selenium in the real samples (pills) is described in this work. The optimum conditions of UV-photochemical generation of volatile compounds was investigated. After that the limit of detection as low as 58 ppt for Se+IV and 30 ppt for Se+VI was obtained. The nutrition supplement, which contain selenium, was choosen and analyzed by this method. Iodide and cupric interfere the determination of selenium in the real samples.
Hydride generation study for arsenic speciation analysis with AAS and AFS detection
Svoboda, Milan ; Dědina, Jiří (advisor) ; Spěváčková, Věra (referee) ; Komárek, Josef (referee)
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...
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 : 47 records found   1 - 10nextend  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.