|
|
Problems of humic matters as precursor of trihalomethanes (THMs) in water
Jelínková, Zuzana ; Dolejš, Petr (referee) ; Doležalová Weissmannová, Helena (advisor)
The bachelor’s thesis deals with qualities of humic matters, their origins, structures and occurrence in aquatic environment. There are suitable methods for determination of humic substances and processes used for their removing from water. The thesis describes disinfection of water and related origin of trihalomethanes. The aim of the experimental part of the thesis is to coagulate model humic water on the laboratory mixing column including suggestion of optimal dose of selected coagulation agent and comparison of effectivity of floccules separation by membrane filtration and centrifugation. Effectivity of the removal of humic matters was determined by measuring water absorbance at wavelengths 245 nm in a silica cuvette with optical 1 cm trajectory and at 387 nm in a glass cuvette with optical 5 cm trajectory. For evaluation of quality suspension concentration of residual iron of coagulation agent in water was determined.
|
|
|
Aplikace nanobublin ozónu v intenzivní akvakultuře
KONONOV, Maksim
The aim of this bachelor thesis was to test the effects of different ozone nanobubble concentrations (O3NB), as a new perspective method of water disinfection in aquaculture, on early ontogeny (the embryonic and larval period) of rainbow trout (Oncorchynchus mykiss) in a hatchery with a pond water (i.e. organically polluted water) source. During this work, two experiments with various O3NB concentrations ranging from 192 +- 40 to 610 +- 122 mV ORP (group 1: 192 +- 40, 2: 277 +- 104, 3: 392 +- 134 a 4: 610 +- 122 mV) in combination with two different husbandry treatments (with/without removal of dead eggs and individuals) were conducted. In the first experiment (N, groups 1-4 N), unfertilized eggs and dead individuals were not collected, in contrast to the second experiment with collection of dead individuals (S, groups 1-4 S). Testing of the above groups (1-4 N/S) was performed in four replicates (aquariums A, B, C, D). Hatching rate was higher in all tested groups of the experiment S. The highest hatching rate (approximately 75 %) was observed in groups 1S, 2S and 3S (ORP 192 +- 40 to 392 +- 134 mV ORP). Fish mortality rate was higher in all groups tested during the experiment N. The highest fish mortality rate (higher than 75 %) was observed in all groups 3N and 4N/S (ORP 392 +- 134 to 610 +- 122 mV). At hatching, the yolk sac volume negatively correlated with O3NB concentration during both experiments. The yolk sac (as an energy source) was faster fully absorbed in fish reared in groups with lower O3NB concentration in comparison with the highest O3NB treatment, when the absorption was markedly slower. The total body length of fish was significantly affected by O3NB concentration during both experiments. The slowest growth was recorded in group with the highest O3NB concentration (ORP 610 +- 122 mV) compared to other groups (ORP from 192 +- 40 to 392 +- 134 mV). The microbiological analyses showed decreasing amount of water microorganisms with increasing O3NB concentration. In summary, the O3NB concentrations in range ORP 192 +- 40 to 394 +- 134 mV), ideally in combination with treatment S, can be recommended for rearing of early stages (embryos and larvae) of rainbow trout. Further research on O3NB in aquaculture is highly required, as there is still a lack of information regarding this perspective technology.
|
|
|
Mikrobiologie balených minerálních vod
Böhmová, Martina
The topic of bachelor thesis is microbiology of bottled mineral water. First is defined what mineral water is and how is divided. Other chapters are focused on bottled water. Here are explained terms such as natural mineral bottled water, spring bottled water, baby bottled water and bottled water. Further are described general requirements for bottled water where the microbiological, physical and chemical indicators belongs. Follows the chapter of microbiology water which mainly deals with an indicator microorganism and the risk of microbial contamination of bottled water. The last chapter of literature is review of water disinfection which is focused on chlorination, ozonation, ionization and water disinfection using ultraviolet radiation. Finally was conducted microbiological analysis of selected types of mineral waters. In the samples was determined by the number of culturable micro-organisms at temperature of 22 °C and 36 °C. At the end were the results anylysis compared with the requirements of notice no. 275/2004 Sb.
|
|
|
Scattering of Sun Radiation on Microparticles in a Closed Environment of Water Bath
Jelínek, Marek ; Pecen, Josef (advisor) ; Zeman, Josef (referee)
This thesis deals with an alternative technology used to illuminate spaces without access to daylight. Technology uses primarily scattering and also reflection and refraction of sunlight in the optical environment of the PET bottles with water and microparticles. The base of technology consists of a plastic bottle filled with water with microparticles and positioned so that it vertically penetrates the roof interior. The effect of scattering of sunlight in the bottle is amplified by using a suitable material of the microparticles.
Review of literature deals with areas that the technology is primarily designed for and the current state of expansion. The principle of technology and factors affecting its efficiency are explained.
The aim of the experiment was limited testing and selection of suitable material of microparticles and their concentration for the possibility of practical use within the technology described. Several measurements were performed of the intensity ratio of incident and scattered light using selected materials of microparticles of various concentrations. Based on the obtained values and their comparison a solution containing 0.5 g of limestone into 1.5 l of water was selected as the most suitable optical environment for the solution.
|
|
|
Problems of humic matters as precursor of trihalomethanes (THMs) in water
Jelínková, Zuzana ; Dolejš, Petr (referee) ; Doležalová Weissmannová, Helena (advisor)
The bachelor’s thesis deals with qualities of humic matters, their origins, structures and occurrence in aquatic environment. There are suitable methods for determination of humic substances and processes used for their removing from water. The thesis describes disinfection of water and related origin of trihalomethanes. The aim of the experimental part of the thesis is to coagulate model humic water on the laboratory mixing column including suggestion of optimal dose of selected coagulation agent and comparison of effectivity of floccules separation by membrane filtration and centrifugation. Effectivity of the removal of humic matters was determined by measuring water absorbance at wavelengths 245 nm in a silica cuvette with optical 1 cm trajectory and at 387 nm in a glass cuvette with optical 5 cm trajectory. For evaluation of quality suspension concentration of residual iron of coagulation agent in water was determined.
|
guest ::
