National Repository of Grey Literature 7 records found  Search took 0.00 seconds. 
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...
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...
The Traffic Education of 4th and 5th Class Pupils of Primary Schools in the Pelhřimov District.
LINHART, Ondřej
Annotation This thesis observes the important aspects related to traffic education of pupils in primary schools. It is especially concentrated on the age group of pupils 4th and 5th grades. The thesis includes a theoretical part dealing with the specifics of traffic education. An individual chapter is devoted to aims, that should be in the context of education - learning influence on children met. The next chapter, which analyzes the fundamental phenomena involved in the formation of key competencies of young road users. They are family, school and children's traffic playground. The actions of these institutions have a common aim, namely to equip students both theoretical knowledge and practical skills and learn to act in accordance with them in protecting the health and lives of children and adults. The following chapter focuses on risk behavior in traffic, the consequences of which proves absolutely alarming statistics on traffic accidents of children. Other chapters bear titles Pedestrian and Cyclist point to the correct interpretation of these concepts and their respective meetings in real traffic. The last chapter in this part of the thesis consists of BESIP. The aim was to highlight the vital role in many areas of its operations. The approach is its history and present, as well as the function of regional coordinators and a number of actions relating to road safety in the Czech regions. The practical part is represented with two individual chapters. The first is a list of research involving the participating primary schools set requirements and main observed factors. The second part presents the methodology of the questionnaire, its subsequent detailed analysis and finally a summary of the results, which bears some predictive value of realized investigations. This is a comparison of the collected written material with a focus on positive response. The aim of the research was to uncover the knowledge levels of respondents to compare the knowledge of boys and girls, and to compare the awareness of the 4th and 5th grades of primary schools. The aim of the research was to uncover the knowledge levels of respondents to compare the knowledge of boys and girls, and to compare the awareness of the 4th and 5th grades of primary schools. The thesis concludes a summary of the findings. In the annexes are placed tables, graphics and the full questionnaire completed for students.
Speciation Analysis of Selected Mercury Compounds Using HPLC, UV-Photochemical Cold Mercury Vapor Generation and its AAS Detection
Linhart, Ondřej ; Červený, Václav (advisor) ; Spěváčková, Věra (referee)
The mercury occurs in the environment in a variety of forms. Mercury compounds can be found in the soil, atmosphere, water and living organisms. Although some of the mercury substances are very toxic, they are often used in various sectors of industry, agriculture and medicine. Mercury compounds differ in their toxicity, so it is necessary to do speciation analysis. The aim of this diploma thesis was to develop and validate a new analytical method for the determination of mercury compounds in different samples. This method involves the combination of high performance liquid chromatography, UV-photochemical cold vapor mercury generation and atomic absorption spectrometry. Effective separation of mercury(II), methylmercury(I), ethylmercury(I) and phenylmercury(I) ions and subsequent comparable efficient of mercury cold vapor generation from all of forms was achieved using these techniques. The reached detection limits were 8 µg l-1 , 31 µg l-1 , 16 µg l-1 and 38 µg l-1 . At the end of experimental work, the proposed method of RP-HPLC-UV-CVG- QTAAS was used for the determination of mercury compounds in real samples (fish tissue and water samples: Labe, Vltava and tap water) and in certified reference materials (DORM-3 and DOLT-4). Several methods for extraction of mercury species from solid samples...
Possibilities of electrochemical generation of volatile compound of silver
Linhart, Ondřej ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
The presented bachelor thesis is to focus on the possibilities of electrochemical generation of volatile form of silver coupled with atomic absorption spectrometry which was used as a detection technique. The main aim was to optimize working parameters. A thin-layer electrolytic cell and a tubular electrolytic cell have been tested for the electrochemical generation of volatile form of silver. The optimization of appropriate electrolyte, its concentration and its flow rate, electric current and flow rate of carrier gas have been developed. Under the optimal working conditions the sensitivity of 0.029 dm mg-1 for the determination of silver by electrochemical generation was achieved.
The utilisation of social network data in BI
Linhart, Ondřej ; Pavlíček, Antonín (advisor) ; Jaroš, Vladimír (referee)
The thesis deals with the topic of social networks, particularly with the opportunities the utilisation of social network data can provide to an enterprise. The thesis is divided into two parts: The theoretical part contains definitions of the terms of data, information and knowledge, followed by descriptions of Business Intelligence and Big Data -- the two means of data analysis in an enterprise, and later by describing social networks themselves. The practical part contains an analysis of the data provided by social networks Facebook and Twitter, and at the same time defines the process of data extraction. The outcome of the analysis is a set of data that may possibly be obtained by the enterprise. This data is then used to determine the possible ways in which enterprises can leverage the data for their business. Finally data provided by Czech e shop is used to provide an example of how an entity can utilise social network data.

See also: similar author names
7 LINHART, Ondřej
1 Linhart, Otto
Interested in being notified about new results for this query?
Subscribe to the RSS feed.