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Separace chirálních pesticidů pomocí cyklodextrinů kapilární elektroforézou
Denková, Barbora ; Polášek, Miroslav (oponent) ; Jáč, Pavel (vedoucí práce)
V této diplomové práci je představena předběžná studie využití EKC-PF (s cyklodextrinem, jako chirálním selektorem) pro separaci chirálních pesticidů. Úvodem jsou prezentovány teoretické informace týkající se přístrojového vybavení, teorie elektroforézy jakož i různých elektroforetických technik. Dále je zmíněna problematika chirálních separací pomocí CE, využití cyklodextrinů jako chirálních selektorů v CE a možnosti techniky částečného plnění kapiláry. Nakonec jsou definovány chirální pesticidy a uvedeny informace o separaci jejich enantiomerů. Experimentální část se zabývá hodnocením separace enantiomerů některých pesticidů (trichlorphon, cyprokonazol, hexakonazol, imazalil, myklobutanil, penkonazol, tebukonazol, propikonazol, a benalaxyl) pomocí CM-β-CD, jako chirálního selektoru. Nejprve byla provedena univariantní optimalizace separačních podmínek (doba nástřiku CM- β-CD, napětí, teplota, pH, povaha a koncentrace elektrolytu) u benalaxylu. Dále byl realizován screening efektu nástřikového času CM-β-CD na rozlišení a migrační časy u ostatních pesticidů se záměrem zjistit potenciál tohoto CD jako chirálního selektoru pro enantioselektivní separaci tohoto typu analytů.
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Tvarová dynamika křemičitých struktur u modelových populací chrysomonád (Synurophyceae)
Pichrtová, Martina ; Němcová, Yvonne (vedoucí práce) ; Elster, Josef (oponent)
The aim of the proposed diploma thesis was to analyze temperature and pH related shape variation in synurophyte silica scales. Four species were investigated - Synura petersenii, S. echinulata, S. sphagnicola and Mallomonas tonsurata. The strains were cultivated in 5 different temperature levels. Moreover, S. petersenii and M. tonsurata were grown in 4 (resp. 5) different pH levels, too. The shape dynamics of the scales was investigated with application of landmark based geometric morphometric methods. The relative warps analysis described the overall shape and the main trends in morphological variation were depicted as deformation grids. The effects of both cultivation temperature and pH on the scale shape were significant, although only a small proportion of the overall variation was explained by the particular regression models. Moreover, the scale size of the investigated species decreased with increasing temperature (with the exception of Synura echinulata). These results are in agreement with the Atkinson's temperature rule which was formulated for the body size of ectotherms. The relationship between the size and pH was not explicit - the size of the scales decreased with increasing pH in S. petersenii, but increased in M. tonsurata. Furthermore, the scale shape was also found to be related to the...
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Effect of high temperature and water shortage stresses duration during anthesis on the selected winter wheat yield formation components
Hlaváčová, Marcela ; Rapantová, Barbora ; Surá, Kateřina ; Klem, Karel ; Hlavinka, Petr ; Trnka, Miroslav
The aim of this study was to assess the effect of drought and high temperatures on Tobak winter wheat variety during one of the most sensitive developmental stage (anthesis) from the viewpoint of harvest index (HI) and spike productivity (SP). The 5 growth chambers (where the plants were exposed to these stress factors) were used for these purposes. The various protocols consisting in photosynthetically active radiation (PAR) course, relative air humidity (RH) and daily temperature courses were run. The plants were divided into 2 groups within each growth chambers: (1) Drough-stressed (Dry) and (2) well-watered (Wet). Two lengths of stresses duration were tested: 3 and 7 days. The plants were exposed to ambient weather conditions up to the full maturity after stresses exposition within the growth chambers. Subsequently, the plants were harvested manually and HI and SP were evaluated. The statistical analyses showed that the effect of each stress factor separately was statistically significant both for HI and SP14, nevertheless, these two factors interaction was statistically significant only in the case of HI.
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Effect of drought stress on selected winter wheat yield formation components within pot and field experiimental design
Hlaváčová, Marcela ; Pohanková, Eva ; Klem, Karel ; Hlavinka, Petr ; Trnka, Miroslav
The object of this study was to find out what is the behaviour of the same winter wheat variety (Bohemia) plants cultivated within pot and field experiment. Therefore, the main aim of this study was to verify (based on the pot experiment results) whether the pot experiment (that is limited by the soil area) does not substantially affect plant reactions. The pot experiment was carried out in growth chambers where daily temperature course, relative humidity (RH) and photosynthetically active radiation (PAR) were set via protocols. The pots were exposed to the drought stress for 14 days with the daily maximum temperature 26 °C from noon to 2 p.m. The pots were split into 2 groups: (1) Dry where the soil moisture within pots were maintained below 30% of the maximum water holding capacity, (2) Wet where the soil moisture did not decrease below 70% of the maximum water holding capacity. The plants within Wet variant were considered as a control group. The pots were placed onto the concrete floor of a vegetation hall (where the plants were exposed to the weather conditions) prior and after stress regime exposition. The field experiment was conducted within experimental station in Bystřice nad Pernštejnem belonging to the Bohemian-Moravian Highlands in the Czech Republic. The drought stress was established through the transparent roofs installed above plants’ tops level in the field. The control experimental plot without roofs was nearby there as well. The plants were harvested when the full maturity was reached and the selected yield formation components were evaluated.
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Fracture Behaviour of Steels and Their Welds for Power Industry
Al Khaddour, Samer ; Kohout, Jan (oponent) ; Válka, Libor (oponent) ; Dlouhý, Ivo (vedoucí práce)
The aim of the study is to verify the validity of the master curve concept for evaluation of the dissimilar weld joint and/or thermally aged weld joints. In addition, the thesis is focused on development of quantitative models for the prediction of reference temperature characterising position of the fracture toughness transition on the temperature axis using experimental data collected from tensile tests, together with a powerful computational technique known as neural network. This study focuses on the evaluation of the fracture behaviour of welds carried out by fusion welding. It aims to investigate the fracture behaviour in transition region of the structural steels and welds with ferritic basic microstructures by means of reference temperature. In order to obtain the reference temperature artificial neural network is used exploting tensile test and hardness test data. Creating a model using neural network method requires a sufficient amount of data and it is sometimes not possible to accomplish easily. Creating a truly general model requires a combination of data and metallurgical knowledge. So, the aim of this work is also to develop artificial neural network enabling to predict the reference temperature. In total 29 experimental data sets from low alloy steels have been applied to validate the model of reference temperature prediction. The tensile tests have been done at general yield temperature of circumferential notched tensile tests (purely general yield temperature) and at room temperature (purely ductile fracture temperature). To build the model all parameters of tensile test and hardness values were used as input variables. The study indicated that the reference temperature characterizing the fracture toughness transition behaviour in low alloy steels with predominantly ferritic structure is predictable on the basis of selected characteristics of tensile test.
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Vliv vybraných faktorů na výnos a zdravotní stav zelí hlávkového, mrkve a cibule kuchyňské
Koudela, M. ; Novotný, Čeněk ; Nedorost, L. ; Kocourek, F. ; Svozilová, L. ; Brožová, L. ; Doležalová, J. ; Kubíček, M.
Předkládaná metodika sumarizuje výsledky polních experimentů, ve kterých byl hodnocen vliv vybraných faktorů na rozvoj důležitých chorob: 1. u zelí hlávkového v letech 2012 – 2013 alternariová skvrnitost brukvovitých (původce Alternaria brassicicola), 2. u mrkve v letech 2012 – 2013 alternariová skvrnitost listů mrkve (původce Alternaria dauci) a u cibule kuchyňské v letech 2013 – 2014 plíseň cibule (původce Peronospora destructor) a krčková hniloba cibule (původce Botrytis aclada). Hodnocenými faktory byly: odrůda, hustota porostu (u mrkve a cibule kuchyňské), ročník a stanoviště. U hodnocených odrůd je nutné přihlédnout k jejich ranosti, která je rovněž důležitým aspektem odolnosti odrůdy k patogenům. V příloze metodiky jsou grafy znázorňující průběh teploty a vlhkosti vzduchu a délky ovlhčení listů v jednotlivých letech na obou pokusných stanovištích (v Praze Troji a ve Svijanském Újezdě). Průběh těchto veličin (v interakci s ostatními faktory) v jednotlivých letech výrazně ovlivňuje rozvoj fytopatogenních hub na napadených rostlinách.
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PIV and LIF study of flow and thermal fields of twine plumes in water
Broučková, Zuzana ; Trávníček, Zdeněk
Flow and thermal fields of a pair of plane plumes in water are investigated using PIV and LIF experiments. The plumes are generated from thermal line sources (electrically heated cylinders, diameter D = 1.21 mm). Either continuous or pulsating heating were used with the same heating input power. For a continuous heating, low frequency oscillations were identified and the natural frequency was evaluated as 0.5 Hz. Pulsating heating was used at frequency of 0.25 Hz. The maximum time-mean velocity magnitude at the continuous and pulsating heating were commensurable, approximately 0.007 m/s. Temperature fields reasonably agree with these findings.
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Temperature and pressure correlation for volume of gas hydrates with crystal structures sI and sII.
Vinš, Václav ; Jäger, A. ; Hielscher, S. ; Span, R. ; Hrubý, Jan ; Breitkopf, C.
The temperature and pressure correlations for the volume of gas hydrates forming crystal structures sI and sII developed in previous study [Fluid Phase Equilib. 427 (2016) 268], focused on the modeling of pure gas hydrates relevant in CCS, were revised and modified for the modeling of mixed hydrates in this study. A universal reference state at temperature of 273.15 K and pressure of 1 Pa is used in the new correlation. Coefficients for the thermal expansion together with the reference lattice parameter were simultaneously correlated to both the temperature data and the pressure data for the lattice parameter. The new correlation is in good agreement with the experimental data over wide temperature and pressure ranges from 0 K to 293 K and from 0 to 2000 MPa, respectively. The new correlation provides significantly better agreement with the experimental data for sI hydrates compared to the original correlation. The results of both correlations are comparable in case of sII hydrates.
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Development of Boundary Layer on a Heated Flat Plate
Antoš, Pavel ; Kuznetsov, Sergeii
An experimental study of boundary layer on a flat plate with heat transfer was done. Temperature and velocity boundary layer development was studied on a uniformly heated flat plate with zero pressure gradient by means of hot-wire anemometry. Several levels of heat flux at the wall were used. The difference between the wall temperature and free-stream temperature was set up to 180 K. Measurements were performed in the closed-circuit wind tunnel with zero pressure gradient at free-stream velocity of 3-5 m/s and turbulence intensity of 0.8 percent. The velocity and the temperature profiles of mean values and fluctuations are presented.
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