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Transition metal oxides for chemical sensors
Volfová, Lenka ; Tyrpekl, Václav (advisor) ; Zelinger, Zdeněk (referee) ; Myslík, Vladimír (referee)
Outdoor air pollution is one of the main environmental problems today. Its monitoring is, among other things, given by the European Union directive (2008/50/EC) on air quality and places high demands on the quantity and reliability of sensors deployed in our immediate surroundings. In order to continuously monitor large number of habitats, it is necessary to develop simple and inexpensive types of sensors. Figure 1 shows an example of such a sensor. The topic of the dissertation is the preparation by physical methods and the study of the surfaces of thin oxide layers as an active medium for the above-mentioned applications. The thesis investigates the possibility of materials preparation by pulsed laser deposition, discharge in a hollow cathode and magnetron sputtering thin film materials for chemiresistor sensors based on copper and tungsten oxides, luminescent Eu doped ZnO layers and resonant so-called QCM, where a quartz resonator was covered with a layer of black aluminium showing a large specific surface in order to increase the sensitivity of these types of sensors. Since the state and properties of the surface are crucial for the function of these types of sensors, an integral and important part of the work is the characterization of the structural properties of the prepared layers,...
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Teachers' approach to socially disadvantaged children
Volfová, Lenka ; Greger, David (advisor) ; Kubišová, Zuzana (referee)
The aim of this thesis is to comprehensively describe the opinions of teachers regarding education of socially disadvantaged children. In order to achieve this aim a questionnaire survey was carried out among teachers of preparatory classes, first and fourth grades. The questions covered four areas: general readiness of schools for education socially disadvantaged pupils, educational training and level of competence, teaching practice and the relationship to the family of the pupil. The research was based on a theoretical framework that describes the current situation and possible changes concerning the education of children from socially deprived groups. The range of sample together with the variety of the sample, which corresponds to the population of teachers, it allowed us to generalize the data. This research provides new empirical evidence of teachers' opinions about the issues of education of socially disadvantaged children from as well as the basis for the implementation of such measures that can aid the relationship between teacher and pupil from socially deprived groups.
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Iron Functionalized Nanoparticles of Titanium Dioxide
Volfová, Lenka
Diploma thesis Iron Functionalized Nanoparticles of Titanium Dioxide Lenka Volfová 2017, ABSTRACT Iron-functionalized TiO2 were obtained by hydrolysis of aqueous solutions of titanyl sulfate with addition of ferric nitrate with ammonium hydroxide and the reaction filtered and washed with hydrogen peroxide. The colloid solutions thus prepared were lyophilized and the products were subsequently annealed at three different temperatures of 650 řC, 800 řC and 950 řC. The prepared doped materials were characterized by powder X-ray diffractometry, electron microscopy, infrared spectroscopy, Mössbauer spectroscopy, UV/VIS spectroscopy, thermogravimetric analysis and differential thermal analysis, and measurement of the specific surface area. Photocatalytic activity was determined by measuring of the decomposition of kinetics of 4-chlorophenol in an aqueous solution in the ultraviolet and visible area. For comparison of activity in the UV area and in the visible area were used a previously prepared highly photoactive specimen and standard TiO2 from Kronos, respectively. Keywords: Doped titanium dioxide, nanostructure, X-ray diffraction, electron microscopy, Mössbauer spectroscopy, suppression of photoactivity
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Natural communication with the horse and the possibility of interaction horses and humans
Volfová, Lenka ; Jančaříková, Kateřina (advisor) ; Říhová, Dagmar (referee)
TITLE: Natural communication with the horse and the possibilities of human - horse interaction AUTHOR: Bc. Lenka Volfová DEPARTMENT: Department of Biology and Enviromnental Studies (Katedra biologie a enviromnentálních studií) SUPERVISOR: PhDr. Kateřina Jančaříková, Ph.D. ABSTRACT: This thesis explores interspecies communication and, specifically, natural communication between the man and the horse. Through comparative research based on a programme developed by Ing. Josef Liška (Liška Solutions) for the assessment of the participant's personality, employing several exercises with a horse from the ground, the thesis aims at introducing ways in which horses can be used for the purposes of personal growth. For the purposes of this thesis, volunteers from three groups were assessed under this programme using the method of direct observation: teachers, business executives and people who work with animals. The assessment was carried out by marking down points and comments. On the basis of the results obtained, the above three groups were subsequently compared among one another. The research shows that teachers excelled in six out of seven observed personal competencies while, compared to business executives, there is still space for improvement in terms of their energy. The results shown in relation to the...
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Iron Functionalized Nanoparticles of Titanium Dioxide
Volfová, Lenka ; Nižňanský, Daniel (advisor) ; Tabor, Edyta (referee)
Diploma thesis Iron Functionalized Nanoparticles of Titanium Dioxide Lenka Volfová 2017, ABSTRACT Iron-functionalized TiO2 were obtained by hydrolysis of aqueous solutions of titanyl sulfate with addition of ferric nitrate with ammonium hydroxide and the reaction filtered and washed with hydrogen peroxide. The colloid solutions thus prepared were lyophilized and the products were subsequently annealed at three different temperatures of 650 řC, 800 řC and 950 řC. The prepared doped materials were characterized by powder X-ray diffractometry, electron microscopy, infrared spectroscopy, Mössbauer spectroscopy, UV/VIS spectroscopy, thermogravimetric analysis and differential thermal analysis, and measurement of the specific surface area. Photocatalytic activity was determined by measuring of the decomposition of kinetics of 4-chlorophenol in an aqueous solution in the ultraviolet and visible area. For comparison of activity in the UV area and in the visible area were used a previously prepared highly photoactive specimen and standard TiO2 from Kronos, respectively. Keywords: Doped titanium dioxide, nanostructure, X-ray diffraction, electron microscopy, Mössbauer spectroscopy, suppression of photoactivity
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Preparation and characterization of the photocatalytic active TiO2 nanoparticles
Volfová, Lenka ; Nižňanský, Daniel (advisor) ; Lančok, Adriana (referee)
Bachelor thesis Preparation and characterization of the photocatalytic active TiO2 nanoparticles Lenka Volfová 2015, ABSTRACT The present work concerns the preparation of photocatalytically active TiO2 nanoparticles, their characterization and study of their photocatalytic properties. The colloidal solution was obtained by hydrolysis of aqueous solutions of TiOSO4. The samples were lyophilized and the product was annealed at 500 řC, 650 řC, 800 řC and 950 řC. The microstructure, morphology and other characteristics of the products were analysed by several physical and chemical methods: X-ray, EPR, SEM, HRTEM and BET. The measurements of IR, UV/VIS and DTA spectra have also been carried out. Photocatalytic activities were investigated by measurement of kinetics of degradation of 4-chlorophenol or methylene blue aqueous solutions under UV light. Measurement of photocatalytic activity of the samples was compared with the standard Degussa P25. It was found that the efficiency of the samples was higher than the standard. Keywords: hydrolysis, titania nanoparticles, microstructure, photocatalytic activity, photocatalytic degradation
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Teachers' approach to socially disadvantaged children
Volfová, Lenka ; Greger, David (advisor) ; Kubišová, Zuzana (referee)
The aim of this thesis is to comprehensively describe the opinions of teachers regarding education of socially disadvantaged children. In order to achieve this aim a questionnaire survey was carried out among teachers of preparatory classes, first and fourth grades. The questions covered four areas: general readiness of schools for education socially disadvantaged pupils, educational training and level of competence, teaching practice and the relationship to the family of the pupil. The research was based on a theoretical framework that describes the current situation and possible changes concerning the education of children from socially deprived groups. The range of sample together with the variety of the sample, which corresponds to the population of teachers, it allowed us to generalize the data. This research provides new empirical evidence of teachers' opinions about the issues of education of socially disadvantaged children from as well as the basis for the implementation of such measures that can aid the relationship between teacher and pupil from socially deprived groups.
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Implementing Ethical education in the school curriculum
Volfová, Lenka ; Voda, Jan (advisor) ; Trunda, Jiří (referee)
In my theoretical part I deal with a quite new educational issue - ethical education. I mean to emphasise the key importace of ethics for society and I describe ethical education as a school subject. I deal with management operations of leading a change in school curricula. The research survey is focused on obstacles within ethical education implementing. Identification of the obstacles is the output as well as a model procedure of ethical education implementing. KEY WORDS Globalization, social atmosphere, achal atmosphere, leading of a change, style sof leading, change implementing
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