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Ecology in lighting
Špidlík, Jan ; Štěpánek, Jaroslav (referee) ; Krbal, Michal (advisor)
This bachelor’s thesis is focused on introduction to ecology in lighting technology. There are briefly described individual light sources and chemical substance used in the manufacture of components. For clarity is amount of toxic mercury in each light source displayed in well-arranged picture. Thesis is also focused on the influence of lighting technology in the environment and impact on the ecosystem. Closer look is made upon influence of mercury on environment and human life and also overall influence of mining metals and its devastating consequences for ecosystem. This work also deals with post processing of light sources by collective systems.
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Study of self-assembly of bacteriochlorophyll aggregates
HOLUBKOVÁ, Lucie
This bachelor thesis is focused on a study of self-assembly of bacteriochlorophyll c isolated from green sulphur bacteria Chlorobium tepidum. These organisms contain special system of light harvesting antennae called chlorosomes. When compare to all other light harvesting complexes chlorosomes are build up from self-assembling aggregates of bacteriochloropyll c. The aim of this work was to study the influence of the length of the side esterifying alcohol on the self-assembly of these pigments. We have prepared methyl-bacteriochlorophyllide c, which is chemically modified bacteriochlorophyll c, where a farnesyl side chain is exchanged for a methyl. The exchange of the methyl for farnesyl led to a loss of the ability of bacteriochloropyll c to constitute self-assembled dimers in water environment. Our results support the idea, that the dimers of bacteriochlorophyl c are build by a hydrophobic interaction of the side esterifying alcohols.
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Povrchová úprava dřevěných fasád
Slováčková, Hana
This thesis deals with monitoring changes in surface finishing of spruce and larch wood in outdoors. Using outdoor weathering tests the properties of two kinds of paints were tested by - a thin glaze and oil paint, two shades from each. In this work, the influence of the composition of the paint on its durability and light fastness was examined. This issue is closely related to the resistance of coatings to weathering, including solar radiation (UVA and UVB), atmospheric oxygen, relative humidity, temperature, precipitation, biological attack, chemical impacts (air pollution, acid rain, etc.).
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The effects of temperature on growth and photosynthesis of C3 and C4 in education
Máhrlová, Zuzana ; Albrechtová, Jana (advisor) ; Kutík, Jaromír (referee)
Photosynthesis, or photosynthetic assimilation, is a set of biochemical processes during which received light radiation energy is changed into energy of chemical bonds. To produce organic compounds, the photosynthesis uses as energy source only light energy and other sources of energy are CO2, mineral nutrients and water. The heat (infrared radiation) is one of the most important external environmental factors affecting plants. Too much of heat or its lack cause plant stress and influence all biochemical processes. Accordin, to the way of CO2 fixation, three types of photosynthesis can recognized- C3, C4 and CAM. Furthermore, C3 and C4 types of plants can be distinguished according to thein optimum temperature range, when C4 plants have optimum temperature ranges generally higher than C3 plants. Another differences between these types of plants consist in different physiological response to the changing climate, above all to the increasing concentration of atmospheric CO2 and simultaneously increasing temperature. The higher the concentration of CO2, the higher the rate of photosynthesis of C3 plants, whereas increased temperature increases the rate of photosynthesis of C4 plants. These different reactions of C3 and C4 plants on different environmental factors have consequences in a rate of net...
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Magnetic orientation in mammals
Tejmlová, Kristýna ; Němec, Pavel (advisor) ; Vácha, Martin (referee)
Earth's magnetic field can provide animal with both directional and positional information. The ability to perceive and utilize information extracted from the geomagnetic field is called magnetoreception. Magnetoreception mechanisms remain largely unknown. Three main hypotheses are currently supported by experimental evidence. The light-independent mechanisms are based either on electromagnetic induction or on biogenic magnetite. The light-dependent mechanism is based on specific chemical reaction between radical pairs. Perception of the geomagnetic field facilitates both long- and short-distance orientation of animals. Some animals exhibit the magnetic alignment, i.e., spontaneuos preference for a certain geomagnetic direction. Another manifestation of magnetoreception is magnetic compass (polarity- or inclination-based, depending on species), which enable an animal to determine the azimuth, i.e., the angle between the direction of motion and geomagnetic field vector. Magnetic map sense enable an animal to determine its position and direction to the goal destination, most likely utilizing the inclination and the intensity of the geomagnetic field as navigational cues. Magnetic orientation of mammals seems to be a widespread phenomenon. Light- independend, polarity compass has been reported in...
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Intermediate host specificity of trematode miracidia
Náhunková, Lucie ; Horák, Petr (advisor) ; Skála, Vladimír (referee)
6 Abstract Trematodes belong to a group of parasitic invertebrate animals of the phylum Platyhelminthes. They have a complicated life cycle. Members of Trematoda have the first larval stage - miracidium. Its primary goal is to find a compatible intermediate host - a mollusc - by use of sensory organs which can respond to various chemical and physical stimuli. Certain signals invoke specific behavior in the outer environment and then miracidium move by taxis or kinesis. They first respond to environmental signals such as light, dark and gravity. The other stimuli are temperature or magnetic force. Then the miracidium locates its host by recognition of highly specific chemical molecules produced by snails. These compounds belong to a group of glycoproteins which are called "miracidia attracting glycoproteins "(MAGs). When the attractant (MAGs) is present, we often observe rate of change of direction"(RCD) and if the concentration of glycoproteins is dropping, then we can observe "turnback swimming" of miracidia. Miracidium has different species specifity towards intermediate host and sometimes species specifity depends on geographic distribution of particular snail hosts of trematodes. Chemoorientation, specificity and behavior of miracidia are very important for trematode development. When the flukes find...
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The optical spectra of carbon-based thin films measured by the photothermal deflection spectroscopy (PDS)
Remeš, Zdeněk ; Pham, T.T. ; Varga, Marián ; Kromka, Alexander ; Stuchlík, Jiří ; Mao, H.B.
Our photothermal deflection spectroscopy (PDS) setup allows to measure simultaneously the absolute values of the optical transmittance T, reflectance R and absorptance A spectra of thin layers on glass substrates in the spectral range from ultraviolet to near infrared light with the typical spectral resolution 5 nm in the ultraviolet, 10 nm in visible and 20 nm in the near infrared region. The PDS setup provides the dynamic detection range in the optical absorptance up to 4 orders of magnitude. Here we demonstrate the usability of this setup by comparing the optical absorbance on a series of the carbon layer and nanocrystalline diamond (NCD) thin layers deposited on glass substrates by using the magnetron sputtering and the microwave based surface wave discharge in linear antenna chemical vapor deposition (CVD) processes, respectively. The defect-induced localized states in the energy gap are observed in all carbon layers as well as in NCD.
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Geochemistry and geochronology of mafic intrusions in the northern part of the Carlsbad pluton
Holečková, Pavla
ii SUMMARY In the NW part of Bohemian massif occur small bodies of mafic intrusive rocks. These rocks are called redwitzites and they include various rock types from diorites to quartz gabbros. They are always close to granites OIC (old intrusive complex). They are probably precursors of Late Variscan granitoid magmatism. Small body of redwitzites is situated near Abertamy (7 km NW of Jáchymov) in the western part of Krušné hory Mts. This body is inhomogeneous; it is formed by two types of mafic rocks. Both rocks distinguish in mineralogy and chemistry. First type, biotitic gabronorite, forms the western part of the body, another type, biotitic - hornblende quartz gabrodiorite, forms the NE part. The expressive sign of Abertamy redwitzites are flakes of brown biotite which can be as large as 2 cm. They are often poikilitic. Gabronorite is a fine-grained green-grey rock consisting of orthopyroxene, biotite, feldspar, quartz and hornblende. Most of the mafic minerals are altered to uralite. Accessories are represented by apatite, zircon, monazite, allanite and sphene. From the chemical point of view is gabronorite enriched in compatible elements (Mn, Fe, Mg, Ni, Cr, Sc, V, Ca, Co, Zn, Cu). Gabrodiorite is medium-grained rock and it is collored light gray. Its composition is similar to the gabronorite. It does...
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Refractometric study of very low density lipoprotein (LDL)
Šinglárová, Simona ; Pacáková, Věra (advisor) ; Staňková, Barbora (referee)
Knowledge of the chemical composition of lipoproteins has a broad meaning. In determining lipoprotein particle size fractions is necessary to preliminary separation by ultracentrifugation in density solutions. Usually the determination is performed by electrophoretic or gel filtration with a suitable detection, which distorts the results. A better solution offers a new detector, called Light Scattering Detector, which detects the bend of laser beam on molecules or particles in solution. To calculate the required particle size dependence on the concentration of the refractive index dn / dc. Concentration is determined gravimetrically and refractive indices by refractometric method. Dependence suits polynomial function. If it correlates with the chemical composition of VLDL lipoprotein can be determined by studying a larger number of samples.
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Preparation and characterization of superparamagnetic inorganic/polymer particles for biomedical application
Zasońska, Beata Anna ; Horák, Daniel (advisor) ; Šafařík, Ivo (referee) ; Sysel, Petr (referee)
Superparamagnetic -Fe2O3 nanoparticles were synthesized by coprecipitation of ferric and ferrous salts with a base. Resulting nanoparticles were coated with shells, such as poly(N,N- dimethylacrylamide) (PDMAAm), neat and functionalized silica (SiO2 and SiO2-NH2), and polyaniline (PANI). PDMAAm shell was introduced by modification of iron oxide nanoparticle surface with an initiator and N,N-dimethylacrylamide was polymerized producing -Fe2O3&PDMAAm core-shell particles. In case of SiO2-NH2 shell, tetramethyl orthosilicate was used to yield -Fe2O3&SiO2 nanoparticles, which were subsequently modified by (3-aminopropyl)triethoxysilane to prepare γ-Fe2O3&SiO2-NH2 particles. Oxidation of aniline hydrochloride with ammonium persulfate in an aqueous solution of poly(N-vinylpyrrolidone) in the presence of iron oxides produced -Fe2O3&PANI nanoparticles. Finally, the last type of the particles was based on thionin-modified poly(carboxymethyl methacrylate) (PCMMA&Th). The particles were characterized by techniques, such as scanning and transmission electron microscopy (SEM and TEM) and dynamic light scattering (DLS) to determine the particle morphology and hydrodynamic diameter. The presence of the functional groups, chemical composition, and the iron content were investigated by Fourier-transform...
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