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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Využití technik hmotností spektrometrie v analýze přírodních látek / Using of techniques of mass spectrometry in the analysis of natural compounds

Vopelková, Alžběta January 2020 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Bc. Alžběta Vopelková Supervisor: doc. Ing. Lucie Cahlíková, Ph.D. Title of diploma thesis: Using of techniques of mass spectrometry in the analysis of natural compounds This diploma thesis deals with the topic " Using of techniques of mass spectrometry in the analysis of natural compounds ". The aim of the work was to create a research work and describe the profile of alkaloids in individual genera of the family Amaryllidaceae. The introduction to the theoretical part summarizes the analyzes gas chromatography (GC). Alkaloids have been classified according to their heterocyclic parts and the family Amaryllidaceae has been described. The work was based on professional texts by Czech and foreign authors. Used sources focused on the analysis of alkaloids in bulbs, or in the aboveground parts of plants in this family, using gas chromatography with mass detection (GC-MS). Key words: mass spectometry, analysis, natural compounds
182

Fenolické látky vo vybraných rastlinných druhoch

Boško, Rastislav January 2017 (has links)
This diploma thesis deals with the analysis of phenolic compounds such as phenolic acids and flavonoids in selected plants, such as ribwort plantain (Plantago lanceolata L.) in which the content of chlorogenic acid, caffeic acid, verbascoside, ferulic acid, rutin and quercetin was monitored. The content of chlorogenic acid, coffee acid, routine, hyperoside, isoquercitroside, tiliroside, quercetin and kaempferol was monitored in small-leaved lime (Tilia cordata Mill.) In addition, the content of chlorogenic acid, caffeic acid, coumaric acid, rutin, hyperoside, isoquercitroside, quercetin and kaempferol was monitored in marigold (Calendula officinalis L.). Also the content of chlorogenic acid, coffee acid, rutin, hyperoside, isoquercitroside, quercetin and kaempferol was monitored in elderberry (Sambucus nigra L.). Similarly the extraction of phenolic compounds from these plants was carried out and subsequently subjected to chromatographic analysis on a UPLC liquid chromatograph with a PDA detector at the Research Institute of Brewing and Malting, Plc.
183

Interakce mezi minerálnimi prvky v dietě brojlerů a jeji vliv na vlastnosti svaloviny

Prokop, Jakub January 2017 (has links)
Diploma thesis deals with influence of mineral elements level in the diet of broiler chickens. Primary observe their importance in meat production with high nutritional and sensory quality. In experiment we tried to modulate the performance of chickens by changing the level of zinc (24 g, 204 g), calcium (2 g, 15 g) and magnesium (1,5 g, 4,5 g) and test the influence on sensory attributes of breast and tight meat. After slaughter in the age of 36 days the meat was processed and frozen stored. In sensory analysis (after heat processing) color, texture, odour, presence of strange odour, tenderness, juiciness, taste and presence of strange taste was judge. We discovered that different level of zinc has negative influence on the odour of tight meat (85,50+-2,108; 77,03+-3,333). Higher level of calcium and magnesium for the breast meat had positive influence on the color (83,53+-2,663; 88,50+-1,731) and negative influence on odour (86,10+-2,428; 76,66+-3,341), chewiness (77,73+-4,157; 63,33+-4,607) and taste (71,83+-4,325; 57,75+-4,532). In the end we can conclude that addition of different levels on mineral elements can influence organoleptic properties of meat and its acceptance for the consumer. It is necessary to do more experiments in this subject in the future.
184

Stanovení vybraných vonných látek v potravinách / Assessment of chosen aroma compounds in foods

Greifenthalová, Ivana January 2013 (has links)
This diploma thesis is focused on the problematic of assessment of 26 most important allergenic aroma compounds in foods, flavoured herbal teas were chosen as the model samples. Aroma is the one of the main characteristics of tea, which is closely linked to taste and odour. The theoretical part of this work is focused on the characteristics of tea, tea types, producing technology, classification according to the fermentation and also their undeniable impact on the human organism. In the experimental part, the allergenic aroma compounds in 10 chosen samples of flavoured tea were identified and quantified using the solid phase microextraction (SPME-GC-FID) in conjunction with gas chromatography. The work also includes sensory evaluation of taste and smell of tea samples by qualified assessors.
185

Sledování (anti-progestagenní aktivity v odpadních vodách pomocí in vitro biotestu / Monitoring of (anti-)progestagenic activity in wastewater by in vitro bioassay

BERANOVÁ, Petra January 2017 (has links)
The aim of this diploma thesis was to detect (anti-)progestagenic activity in wastewater samples from the influent and effluent of six wastewater treatment plants (WWTPs) located in South Bohemia. Subsequently, the efficiency of the treatment process of this WWTPs was assessed from this point of view. The wastewater from WWTPs was transported to the laboratory and extracted oby solid phase extraction. The eluates were washed, evaporated and dissolved in DMSO. Detection of (anti-)progestagenic activity was performed by using the PR-CALUX in vitro bioassay. Transgenic cells were seeded on well plates and were exposed to ORG2058, reference substance for progestagenic activity, or RU-486, reference substance for antiprogestagenic activity, as well as a number of diluted wastewater extracts. After that, luminiscence of the cells was measured and it was was expressed in relative light units which were a measure of (anti-)progestagenic activity.(Anti-)progestagenic activity was reported in equivalent concentrations of the reference substance. Progestagenic activity in WWTPs influent ranged from below LOQ up to 1.8 ng/l ORG2058 eq. In effluent this activity ranged from below LOQ up to 0.5 ng/l ORG2058 eq. The elimination rate of progestagenic activity ranged from -25% to 100%. Antiprogestagenic activity in WWTPs inffluent was below the LOQ up to 1 ng/l RU-486 eq. In effluent this activity was below LOQ up to 9.7 ng/l RU-486 eq. The elimination rate of antiprogestagenic activity ranged from -50% to 100%.(Anti-)progestagenic activity in waste water has been demonstrated by using the PR-CALUX in vitro bioassay. Negative removal efficiency of some WWTPs was also documented. This is probably caused by biotransformation of some substances which don´t have (anti-)progestagenic activity to substances which have this activity or it is caused by deconjugation of metabolits of compounds with (anti-)progestagenic activity. Antiprogestagenic activity may be more hazardous for organisms living in the aquatic environment than progestagenic activity because of concentrations in WWTPs effluent. However this activity should not be underestimated.
186

Fluorescence půdních a lignitických huminových látek / Fluorescence of soil and lignite humic substances

Konečná, Soňa January 2009 (has links)
The purpose the diploma thesis was to determine main fluorophores of soil and lignite humic substances using methods of 2D synchronous fluorescence spectroscopy (SFS) and 3D SFS. These fluorescence methods are frequently used for characterization multifluorophore systems. Measured synchronous spectra were compared with standards IHSS. Next to that the aim was to find differences between chosen samples of humic and fulvic acids.
187

Vliv látek produkovaných sinicemi na koagulaci huminových vod / Influence of compounds produced by cyanobacteria on coagulation of humic waters

Brabenec, Tomáš January 2015 (has links)
The diploma thesis investigates the coagulation of nature waters with humic substances and peptides/proteins produced by Microcystis aeruginosa during water treatment process with aluminum coagulants. It was confirmed that the efficiency of coagulation mechanism of humic substances and peptides/proteins strongly depends on the pH value, because pH value is limited factor of a charge properties of peptides/proteins, humic substances and hyrolysis products of coagulants. The optimal pH range for the coagulation of humic substances was 5- 6 and for cyanobacterial peptides/proteins 5-6.5. In both cases a charge neutralisation and an adsorption were dominant mechanism of coagulation. Optimal pH range for the coagulation of humic substances in the presence of cyanobacterial peptides/proteins was identical as well as optimal pH range of humic substances with absence of peptides/proteins (5-6) but the presence of peptides/proteins positively influenced particle coagulation of humic substances, because the optimal concentration of the coagulants decreased to more than half. An interaction between humic substances and peptides/proteins was demonstrated. A positive effect of coagulation was observed in the case of jar tests with absence of coagulants at a very low pH range (<4). Keywords Humic substances; AOM...
188

Koagulace neproteinové složky látek produkovaných fytoplanktonem / Coagulation of non-protein algal organic matter

Lukeš, Jan January 2017 (has links)
The diploma thesis deals with characterizing properties of non-proteinaceous cellular organic matter (COM) of green alga Chlorella vulgaris in connection with its coagulation using aluminium sulphate and polyaluminiumchloride. As a part of this work, interaction mechanisms were also studied. It has been found out that non-proteinaceous COM of Chlorella vulgaris is made up by saccharides (25 % DOCNP, 21 % of dry biomass of non- protein matter) and other unspecified non-protein substances. It has been found out by fractionation of molecular weights that non-protein COM is formed primarily by substances with MW < 3 kDa and substances with MW > 100 kDa. Coagulation by aluminium sulphate taken place in interval pH 5 - 8,5 and coagulation by polyaluminiumchlorid taken place in interval pH 7 - 10 depending on coagulation agent dose. The maximum DOC removals were 17 - 22 % depending on selected coagulation agent, on its dose and pH. Polyaluminiumchloride showed higher DOC removal rates than aluminium sulphate. The highest effectiveness of coagulation was in the area of neutral pH for both agents. In all the coagulation tests the values of residual concentrations of aluminium were higher than the hygienic limit for drinking water (0.2 mg.L-1 ). Primarily high-molecular matter was removed by coagulation and...
189

Prostředky pro automatické podávání antidot (autoinjektory) proti nervově paralytickým látkám / Means for automatic administration of antidotes (autoinjectors)against nerve agents

JONÁŠ, Jindřich January 2012 (has links)
This thesis is dedicated to the topic of the nerve agents with special emphasis on antidotal treatment utilizing application of the auto-injectors. Two methods were used ? literature research and quantitative research. Since this topic covers plenty of information as regards chemical warfare agents and in particular nerve agents these issues were addressed in the theoretical part of the thesis. In the chapter on current status based on literature resources a summary of evolution of the auto-injector is presented; from firsts notes until the situation today. Practical part of the thesis is concentrated on University of Southern Bohemia in ČeskéBudějovice, Faculty of Health and Social Studies students' knowledge in the area of nerve agents. The results of the research were acquired by the method of quantitative research ? questionnaires with 18 questions. With respect to each of the questions a selection of the 2 to 7 answers was offered to the students, whereas in every case only 1 answer was correct. The results were analyzed both with reference to each of the questions and with reference to each of the students. By this method it has been discovered that the respondents have a good knowledge in the area of nerve agents. Furthermore, the practical part of the thesis included an experiment concerning speed with which the respondents were able to apply antidotum with a training auto-injector by themselves with no prior instructions in comparison to how quickly they were able to do the same after being instructed. By this method were tested the quality of the instructions provided to the auto-injectors and its ergonomic qualities (intuitiveness of its application). Recorded times were statistically analyzed and the results, although materially different, were assessed as satisfactory.
190

Vliv omamných a psychotropních látek na chování řidiče a možnosti odhalení v rámci silniční kontroly PČR / Impact of Narcotics and Psychoactive Drugs on Driver´s Behaviour and Possibilities od Detection During Police Road Control

Floreš, David January 2018 (has links)
The result of this diploma thesis is based on the collected data, to evaluate the success of the detection of narcotic and psychotropic substances by a policeman, with subsequent measuring and professional expression. The thesis is divided into three parts. In the theoretical part, this is mainly an evaluation of existing information dealing with drug issues related to road accidents. In the analytical part, the thesis deals with real methods and equipment with OPL detection. The practical part contains data obtained from qualitative research, through interviews, which are compared and evaluated with a quantitative survey of the questionnaire survey, which can help to improve expert judgment and improve transport safety.

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