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Leaf physiological and optical properties in relation to the Phytophtora × alni infection of black alder (Alnus glutinosa)
Oramová, Viktorie ; Lhotáková, Zuzana (advisor) ; Tomášková, Ivana (referee)
A current problem is the infestation of the black alder (Alnus glutinosa) by the pathogen P. × alni, which causes the loss of alder stands and disrupts riparian ecosystems. The spread of the 'phytophthora disease' occurs through water, the host is infected through the root system and the pathogen attacks the conductive tissues. As a result of the disease, the tree gradually loses its root system, lesions appear on the trunk, defoliation occurs and the individual inevitably dies. The only solution to the situation is preventive measures to prevent further spread by careful removal of infected alder trees. The aim of this paper is to discuss the relationship between black alder and P. × alni in the context of the physiological changes that occur in the foliage of the infested individual. Leaf functional traits, chlorophyll fluorescence and optical properties of black alder exposed to P. × alni (inoculation into soil or confirmed occurrence of the pathogen in natural conditions) were measured using non-invasive methods. The results of the chamber experiments suggest that the mean values of the measured parameters do not change significantly in the initial stages of infection, but there is a widening of the variance of the values in infected individuals. We tested whether the genetic origin of the...
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Application of spectrophotometers
Klimešová, Marie ; Čmiel, Vratislav (referee) ; Kolář, Radim (advisor)
The work deals with the important analytical method - spectrometry. It is based on measurement of absorption of radiation in a wavelength range. On this principle can determine the absorbance and transmittance of the measured samples. The thesis also describes events related to the excitation of molecules. These include absorption, vibrational relaxation, internal conversion, inter-system crossing, fluorescence, phosphorescence and delayed fluorescence. The practical part includes three experimental measurements. The first measurement is the concentrations of potassium permanganate solution. In a second experiment, verifying the validity of Lambert-Beer law. In the third experiment, the fluorescence measurement of fluorescein and detection of fluorophore concentration dependence on fluorescence intensity. Measurement is performed in an environment SpectraSuite with the use of school spectrometers USB2000 + and USB650 Red Tide.
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Optical determination of the state of charge of vanadium flow battery cells
Šacl, Vojtěch ; Chladil, Ladislav (referee) ; Novák, Vítězslav (advisor)
The investigated subject for this diploma thesis is getting know properties of the vanadium redox battery (VRB), especially electrolyte. Specialization is applied to the state of charge of this cell and its measurements using the optical methods. Upon different state of charge is changed oxidation number of vanadium and resultant color of the electrolyte. Using spectrofotometry method that characteristic property is undergone measurement. The basic thing was learning to handle a measurement system. The first practical measurement was executed on example foils. Upon measurement of vanadium cell there was obtained the values of absorbation, which they were used for determination of state of charge.
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Spectrophotometry of ROS species with focus on hydrogen peroxide
Zhorný, Lukáš ; Hořavová, Lenka (referee) ; Provazník, Ivo (advisor)
The main theme of this work is spectrophotometry. The first chapter describes the theoretical problems of the topic, relevant units and formulas for calculating the absorbance of the solutions of given concentrations. Further disclosed herein is a spectrophotometer, its individual parts, and the principle on which the unit is based. The last chapter of the theoretical introduction to this work is focused on the production of ROS in living organisms and especially in plants, and then there are some spectrophotometric methods for determining the concentration of ROS. The practical part describes the method using TiCl4 and method using KI. Both methods were used to determine the hydrogen peroxide concentration and subsequent measurement of absorbance of solutions of standard hydrogen peroxide added interfering substances. Then, the statistical analysis of the measured data and the assessment of the impact of these interferents to measure absorbance. The first of these methods proved to be suitable for a given measurement.
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Spectrophotometry of ROS species with focus on hydrogen peroxide
Zhorný, Lukáš ; Hořavová, Lenka (referee) ; Provazník, Ivo (advisor)
The main theme of this work is spectrophotometry. The first chapter describes the theoretical problems of the topic, relevant units and formulas for calculating the absorbance of the solutions of given concentrations. Further disclosed herein is a spectrophotometer, its individual parts, and the principle on which the unit is based. The last chapter of the theoretical introduction to this work is focused on the production of ROS in living organisms and especially in plants, and then there are some spectrophotometric methods for determining the concentration of ROS. The practical part describes the method using TiCl4 and method using KI. Both methods were used to determine the hydrogen peroxide concentration and subsequent measurement of absorbance of solutions of standard hydrogen peroxide added interfering substances. Then, the statistical analysis of the measured data and the assessment of the impact of these interferents to measure absorbance. The first of these methods proved to be suitable for a given measurement.
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Application of spectrophotometers
Klimešová, Marie ; Čmiel, Vratislav (referee) ; Kolář, Radim (advisor)
The work deals with the important analytical method - spectrometry. It is based on measurement of absorption of radiation in a wavelength range. On this principle can determine the absorbance and transmittance of the measured samples. The thesis also describes events related to the excitation of molecules. These include absorption, vibrational relaxation, internal conversion, inter-system crossing, fluorescence, phosphorescence and delayed fluorescence. The practical part includes three experimental measurements. The first measurement is the concentrations of potassium permanganate solution. In a second experiment, verifying the validity of Lambert-Beer law. In the third experiment, the fluorescence measurement of fluorescein and detection of fluorophore concentration dependence on fluorescence intensity. Measurement is performed in an environment SpectraSuite with the use of school spectrometers USB2000 + and USB650 Red Tide.
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Optical determination of the state of charge of vanadium flow battery cells
Šacl, Vojtěch ; Chladil, Ladislav (referee) ; Novák, Vítězslav (advisor)
The investigated subject for this diploma thesis is getting know properties of the vanadium redox battery (VRB), especially electrolyte. Specialization is applied to the state of charge of this cell and its measurements using the optical methods. Upon different state of charge is changed oxidation number of vanadium and resultant color of the electrolyte. Using spectrofotometry method that characteristic property is undergone measurement. The basic thing was learning to handle a measurement system. The first practical measurement was executed on example foils. Upon measurement of vanadium cell there was obtained the values of absorbation, which they were used for determination of state of charge.
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Závislost průniku sluneční radiace na indexu listové plochy lesních porostů
Synakievicz, Petr
Availability of solar radiation for plants at different levels of forest stand is significantly influenced by the amount of solar radiation incident on the stand canopy, by optical properties of the stand and by stand structure. The aim of this bachelor thesis was to evaluate relationship of penetration of solar radiation (photosynthetically active radiation, PAR) on the leaf area index (LAI) of the forest stands in the growing season (May to October) of 2009 and 2010 at the ecological experimental study site of Bílý Kříž (the Moravian-Silesian Beskids Mts., the Czech Republic). The statistical evaluation showed that in the years 2009 and 2010, none of the monitored variables (amount of PAR incident on the stand canopy, amount of PAR penetrating below the stand canopy, leaf area index of the stand) were any statistically significant differences. Average transmittance (ratio of FARt penetrating below the stand canopy and FARi incident on the stand canopy) calculated for the whole growing season (May to October) was ca. 2.5% both in 2009 and in 2010. The maximum value of LAI in 2009 was 9.39 m2 m-2 and 10.06 m2 m-2 in 2010. LAI values were set in the years significantly affected by weather conditions. Analysis has shown that the penetration of solar radiation is highly dependent on the amount of foliage - index leaf area.
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