National Repository of Grey Literature 8 records found  Search took 0.01 seconds. 
Comparison of selected quality indicators of honeys from different countries of the European Union
HOSNEDLOVÁ, Barbora
The topic of the diploma thesis was to compare selected quality indicators of individual samples of honey obtained from the countries of the European Economic Community. The samples of honey were both single-species (chestnut, sunflower, ...) and multi-species (meadow, forest). The theoretical part of the thesis is focused on the characteristics of individual types of honey and their composition. Furthermore, the basic physical, chemical and sensory requirements for honey are described here, according to Czech Decree No. 76/2003 Coll. The practical part contains its own physicochemical analysis according to Harmonized methods of European Honey of the honey samples. Seventeen samples were evaluated. They were evaluated for water content, acidity, and a test was also carried out for evidence of damage to the honey by starch sugar or malt extracts. The results of the compared honey samples show that eight samples were violated by starch sugar or malt extracts, while the criterion for water content was fine and all honey samples complied with the Czech Decree No. 76/2003 Coll.
Assessment of drought response in local Scots pine ecotypes using anatomical, biochemical, and fluorescence stress markers.
Štěpánová, Kristýna ; Lhotáková, Zuzana (advisor) ; Stejskal, Jan (referee)
Global climate change and associated global warming is already a problem for temperate forest ecosystems and will continue to exacerbate the problem in the coming decades. Many species will have to adapt to a multifactorial combination of stresses, with increases in average air temperature, frequency and intensity of precipitation increasing drought episodes and drought-affected areas will enlarge. It is necessary to find ways to help the landscape cope with these intensifying phenomena. The possibility of planting suitable tree species that can manage water efficiently and survive even in periods of intense water scarcity is an option. The drought tolerance of trees is related to their phenotypic plasticity and ecotypic differentiation. Scots pine (Pinus sylvestris L.) is characterised by modest ecological demands on the environment and climate of the habitat, is phenotypically plastic and relatively drought resistant. The objectives of this study were 1) to evaluate and compare the response of different Scots pine ecotypes to drought stress due to reduced water availability using anatomical, biochemical, and fluorescence indicators of physiological status, and 2) to determine the biochemical phenotype of selected genotypes within a local Scots pine ecotype in a seed orchard in terms of...
Upgraded Methodology for Process Intensification in Natural Gas Dehydration
Abdulrahman, Ibrahim ; Jegla, Zdeněk (referee) ; Ditl,, Pavel (referee) ; Máša, Vítězslav (advisor)
Vysoušení zemního plynu, anglicky natural gas dehydration, je zásadní součástí procesu zpracování vytěženého zemního plynu. Klíčová úloha vysoušení spočívá především v podpoře množství a kvality produktu, ale také v prevenci tvorby hydrátů, koroze či nežádoucí vodní kontaminace při transportu plynu. Tento petrochemický proces má všechny předpoklady pro aplikaci tzv. intenzifikace procesů (PI), moderního přístupu z oblasti procesního inženýrství. Jeho intenzifikace je žádoucí z pohledu investičních a provozních nákladů (CAPEX and OPEX), spotřeby energie i produkce nežádoucích emisí. Současné globální požadavky v oblasti ochrany životního prostředí i ochrany zdraví osob umocňují význam těchto snah. V odborné literatuře v posledních letech významně roste zájem o intenzifikovaná zařízení (PI equipment), méně však už o rozvoj metod intenzifikace procesů a jejich aplikaci na komplexnější procesy. Překvapivě málo se také při výzkumu PI využívá počítačové podpory ve formě simulace procesů. Předložená práce představuje novou systematickou metodu pro intenzifikaci procesu vysoušení zemního plynu založenou na počítačové simulaci, která využívá dva hodnotící parametry: jmenovitou spotřebu energie (Rated energy consumption, REC) a předepsaný obsah vody v produkovaném zemním plynu. Spotřeba energie je tvořena přímou spotřebou samotného procesu a entalpickými ztrátami přes hranici procesu. Snižování jmenovité spotřeby energie je klíčovou motivací intenzifikace a současně prostředkem k jejímu hodnocení. Předepsaný obsah vody je klíčovým projekčním a provozním parametrem procesu. Navržená metoda vychází z interakce těchto dvou parametrů. Práce staví na zodpovědném rozlišování mezi intenzifikací konkrétní procesní jednotky a intenzifikací komplexnějšího procesu, který zahrnuje více dílčích jednotek. Využívá přitom efektivní rámec pro implementaci PI v petrochemickém průmyslu, který byl definován autorem práce. Navržená metoda byla aplikována na existující průmyslový provoz zpracovávající vytěžený zemní plyn. Pro analýzu nejčastěji využívané technologie sušení, tzv. triethylenglykolové absorpce (TEG), byl použit výkonný software pro simulaci procesů. Byla provedena citlivostní analýza jmenovité spotřeby energie (Rated energy consumption, REC) této jednotky na změnu tří vybraných proměnných – průtoku triethylenglykolu, teploty v koloně a průtoku stripovacího plynu. Ukázalo se, že tyto proměnné mají obrovský potenciál pro intenzifikaci TEG jednotky. Jejich cílenou změnou je možné snížit jmenovitou spotřebu energie o 11 až 18 %, BTEX emise až o 69 %, emise CO2 až o 37 % a ztráty triethylenglykolu až o 35%, přičemž není negativně ovlivněna předepsaná kvalita produktu. Metoda předpokládá postupné provozní zásahy do procesu a nevyužívá technologických změn. Navržené úpravy jsou proto velmi dobře využitelné při optimalizaci provozu stávajících jednotek glykolové absorpce i návrhu nových. Navržená systematická metoda byla použita i na další jednotky, které předchází a navazují na glykolovou absorpci. Výsledky potvrzují výše uvedený přínos a významný potenciál PI při snižování spotřeby energie, kterého může být dosaženo v rámci celého procesu vysoušení zemního plynu.
Application of imaging spectroscopy in monitoring of vegetation stress caused by soil pollutants in the Sokolov lignite basin
Mišurec, Jan ; Kupková, Lucie (advisor) ; Pavelka, Karel (referee) ; Homolová, Lucie (referee)
Forests can be considered as one of the most important Earth's ecosystems not only because of oxygen production and carbon sequestration via photosynthesis, but also as a source of many natural resources (such as wood) and as a habitat of many specific plants and animals. Monitoring of forest health status is thus crucial activity for keeping all production and ecosystem functions of forests. The main aim of the thesis is development of an alternative approach for forest health status based on airborne hyperspectral data (HyMap) analysis supported by field sampling. The proposed approach tries to use similar vegetation parameters which are used in case of the current methods of forest health status assessment based on field inspections. It is believed that importance of such new methods will significantly increase in the time when the planned satellite hyperspectral missions (e.g. EnMap) will move into operational phase. The developed forest health monitoring approach is practically demonstrated on mature Norway spruce (Picea abies L. Karst) forests of the Sokolov lignite basin which were affected by long-term coal mining and heavy industry and therefore high variability of forest health status was assumed in this case. Two leaf level radiative transfer models were used for simulating spectral...
Fuel properties: Determination of moisture solid fuels
Tretera, Michal ; Musilová, Petra (referee) ; Lisá, Hana (advisor)
This bachelor's thesis deals with the determination of moisture content in solid fuels. First part contains classification of solid fuels, proximate analysis of solid biofuels and a research of methods for determination of moisture content in solid biofuels. Description of impacts of the moisture content on fuel is included in the proximate analysis. Second part of the thesis is experimental. Thirteen solid biofuels and one solid recovered fuel were measured to obtain their moisture content. The methods used to determine the moisture content include four different drying methods and a xylene distillation method. For each method there are details of the procedure and a summary of the results.
Application of imaging spectroscopy in monitoring of vegetation stress caused by soil pollutants in the Sokolov lignite basin
Mišurec, Jan ; Kupková, Lucie (advisor) ; Pavelka, Karel (referee) ; Homolová, Lucie (referee)
Forests can be considered as one of the most important Earth's ecosystems not only because of oxygen production and carbon sequestration via photosynthesis, but also as a source of many natural resources (such as wood) and as a habitat of many specific plants and animals. Monitoring of forest health status is thus crucial activity for keeping all production and ecosystem functions of forests. The main aim of the thesis is development of an alternative approach for forest health status based on airborne hyperspectral data (HyMap) analysis supported by field sampling. The proposed approach tries to use similar vegetation parameters which are used in case of the current methods of forest health status assessment based on field inspections. It is believed that importance of such new methods will significantly increase in the time when the planned satellite hyperspectral missions (e.g. EnMap) will move into operational phase. The developed forest health monitoring approach is practically demonstrated on mature Norway spruce (Picea abies L. Karst) forests of the Sokolov lignite basin which were affected by long-term coal mining and heavy industry and therefore high variability of forest health status was assumed in this case. Two leaf level radiative transfer models were used for simulating spectral...
Selected Qualitative Parameters of Honey Bee Colonies Acquired During the Calendar Year.
JEŘÁBEK, Miloš
Topic of bachelor thesis is "Selected qualitative indicators of honey from different bee hives that were obtained during a calendar year." Main aim of the thesis was to conduct a research of topic given and to compare selected indicators (water content, acidity, electrical conductivity of honey, proof of honey samples being disrupted by starch sirup, starch sugar or malt extracts and other qualitative indicators of honey) from samples of honey that has been collected during a defined period of the year (May, June, July). In the experimental part of the thesis, analysis was performed using defined indicators of quality from selected samples of honey of those that were collected from bees of our own bee hives. European norm for water content in honey was satisfied in 59 samples out of 60. Norm for Czech honey was satisfied in May and June in 9 samples and in July in all 20 samples. Norm for honey acidity and disruption by starch sirup, starch sugar or malt extracts satisfied all 60 samples.
Selected Qualitatives Parameters of Monofloral Honey from The Czech Republic
JURÁKOVÁ, Andrea
The theme of this thesis is a comparison of selected quality indicators of samples from single-flower honeys from the area of the Czech Republic and honeys from different retail chains. The theoretical part focuses on the characteristics of the individual kinds of honey and how different their composition is. There are described basic physical and chemical requirements for honey including sensory requirements which are specified in Regulation No.76/2003 Code. The practical part contains a physically-chemical analysis according to the Harmonized methods of European Honey and a sensory evaluation of selected single-flower honeys (honeydew, acacia, lime, sunflower and rape). There were analysed twenty samples of honey from Czech beekeepers and fifteen samples of honey bought in different retail chains in the Czech Republic. Subsequently, these parameters were monitored - water content and acidity. Next step was a test for evidence of disruption by starchy sugar and malt extracts. Then, sensory requirements such as colour, smell, taste and consistence were evaluated. The conclusion of the comparison of honey samples indicates that individual honey samples differed the most in the taste and smell criteria and in addition the samples were often disrupted by starchy sugar and malt extracts. The samples collected from the beekeepers from the area of the Czech Republic complied with Regulation No.76/2003 Code. On the contrary, the samples from the chosen retail chains in the Czech Republic weren't in accordance with the criteria specified in Regulation No.76/2003 Code.

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