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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.
41

Eigenschaften von gesputterten n+-ZnO/c-Si-Heterokontakten Transport, Grenzfläche und Bandanpassung /

Poschenrieder, Margarethe. Unknown Date (has links) (PDF)
Techn. Universiẗat, Diss., 2000--Berlin.
42

Spectroscopy of polaritonic excitations in semiconductors

Dasbach, Gregor. Unknown Date (has links) (PDF)
University, Diss., 2003--Dortmund.
43

Verdichtung und Kristallisation von transparenten leitfähigen oxidischen Sol-Gel-Schichten am Beispiel des Zinkoxids

Schuler, Thomas. Unknown Date (has links) (PDF)
Universiẗat, Diss., 2003--Saarbrücken.
44

Model bilance uhlíku ("Carbon footprint") na malé a velké farmě

Johaníková, Alena January 2014 (has links)
This thesis deals with load of carbon dioxide on large and small farm, which is subsequently converted by digestibility coefficients of nutrients to the equivalent carbon dioxide. The objects of the calculation are two given farms, located in the Zlín Region. Small farm entertain with 15 pieces of pig sows in a closed herd turnover and large farm breeding cattle herds with a turnover of 100 dairy cows. From the sales of the pig herds on a small farm, I found a total feed consumption, which is 133.5 tons per year, which I calculated the carbon content received from the compound feed, which is 50.35 tons and 3.08 tons of nitrogen per calendar year. Pigs in the feces excrete 8.12 tons of carbon and 0.52 tons of nitrogen. Pigs consume 0.36 tons of carbon and 0.44 tons of nitrogen per ton of edible particles in the meat. To produce 1 kg of meat consumes 0.246 kg of carbon. On a dairy farm income in total 1,645.29 tons of compound feed per year in which they adopt 609.61 tons of carbon and 31.23 tons of nitrogen. In feces they excrete 156.84 tons of carbon and 8.05 tons of nitrogen. In the milk is eliminated 42.78 tons 2.51 tons of carbon and nitrogen. The herd turnover of 31 bulls with the increments 1.4 kg / day 210.53 tons annually consume feed mixtures from which bulls take 71.70 tons, and 3.21 tons of carbon. In feces they excrete 18.09 tons and 1.10 tons of carbon and nitrogen in the meat, at the slaughterhouse is excluded 4.49 tons 0.35 tons of carbon and nitrogen. At the turn of the herd of bulls with the increments of 33.7 1.7 kg / day annually consumes 265.49 tons of feed mixtures from which the bulls take 71.70 tons and 3.21 tons of carbon nitrogen. In feces they excrete 21.35 tons and 1.35 tons of carbon and nitrogen in the meat, at the slaughterhouse is excluded 4.88 tons 0.38 tons of carbon and nitrogen. To produce 1 kg of meat bulls consume 0.248 kg of carbon. In conclusion are recommendations to reduce emissions at the farm which is needed.
45

Komplementární metody k použití oxidu siřičitého

Malík, Marek January 2014 (has links)
This thesis was focused to finding chemicals an other methods that are able to reduce or replace the dose of sulfur dioxide in the wine industry. Introductory chapters deal with sulfur dioxide - its specific characteristics and forms which can be used in wine practice and way of its particular application. It was also processed a large number of literary resources with different complementary methods and provide an overview. Methods, described in this thesis, have been previously tested and they had some potential in reducing sulfur dioxide doses during the production of wine. Thesis mainly describes the interesting physical methods but the most important part of this thesis is description of chemicals with different properties and structures. The main essence of this work was experiment which studied two chemicals to reduce the doses of SO2 -- dimethyldicarbonate and higher fatty acids. The actual experiment was based on the inhibition of the four tested microorganisms in fermenting must of variety 'Marlen' and in saline (only in the case of Brettanomyces bruxellensis). Its output was counting the colonies grown on Petri dishes followed by consequential graphical demonstration of the sensitivity these microorganisms to dimethyldicarbonate and higher fatty acids.
46

Stanovení oxidu siřičitého ve víně standardními i alternativními metodami

Dufek, Petr January 2014 (has links)
This thesis focuses on the study of domestic and foreign literature on the determination of sulfur dioxide in wine. A detailed description of the standard and alternative methods, their analysis, identification of possible shortcomings or disadvantages and specifying strengths and advantages. Theory obtained by studying literature is verified by a several samples of wine are provided different forms of sulfur dioxide with different methods . Subsequently, the results obtained by various methods are compared in terms of accuracy and applicability in the viticultural practice. Everything should be processed in order that the thesis could become an additional study material for university students.
47

Vliv zvýšené vzdušné koncentrace oxidu uhličitého na růst buku lesního

Sokolová, Tereza January 2015 (has links)
Elevated CO2 concentration influences the anatomical, physiological and morphological characteristics of plants, both directly and indirectly. The aim of this thesis was to determine the effect of increased atmospheric CO2 concentration on growth of European beech (Fagus sylvatica). The experiment was carried out from autumn 2005 on environmental work place Bílý Křiž in Beskydy and established in artificial conditions (A-ambient - natural air concentration of CO2 - 385 ppm, E-elevated - 700 ppm, C-control - open control area). Two-year old seedlings of beech and three years old spruces seedlings have been planted in a triangular spacing in lamellar biospheres in a total of 96 individuals. The study is focused on biomass production of beech in different types of mixed cultures together with Norway spruce (P-pure - monoculture, I-Individual -- individual mixing, G-group -- group mixing). In mid August 2013 has begun destruction of beeches, which was completed in September 2013. Aboveground parts were dividend in to group consisting of branches and trunk and roots were subjected to destructive analysis later. Separate parts of the trees were dried in the oven for 48 hours at 80 °C and subsequently 2 hours at 105 °C and then were weighed to determine the biomass. After eight years of experiment, cultivation of spruce and beech in lamellar biospheres, there were no signifiant differences in total biomass of trees between varieties A and E. However, it showed significant influence of CO2 on the biomass of individual organs (leaves, branches, trunks and roots, including stumps ) as well as trees grown in a single mixed culture (I). When comparing the total biomass in the spheres, sphere E showed average total biomass of an individual tree about 27 % higher, in mixed G variety 25 % lower and in the P mixing 147 % higher than mixed I in the sphere A. Biomass production of roots without identification of mixing factor increased by 60 % in the E variety. Most significant difference in belowground biomass was detected in variety of mixing I. In the E sphere was 200 % more belowground biomass compared to sphere A. These preliminary results show that total biomass of beech was higher in sphere E than in the sphere A. Differences in total biomass , however, can be caused by mixing and correspond to the concentration of CO2.
48

Využití uhlíkových materiálů pro studium iontů kovů, kvantových teček a kov-vázajícího laktoferinu

Fialová, Dana January 2014 (has links)
In the present thesis entitled "Utilization of carbon materials for the study of metal ions, quantum dots and lactoferrin binding metal", different forms of carbon for a specific application were used. Nanoforms of carbon, such as carbon nanotubes, reduced graphene oxide and expanded carbon were used for the isolation of heavy metal ions from aqueous solutions. These materials are characterized by high surface area and ability to bind the heavy metal ions on its surface by either physical or chemical adsorption. The influence of the interaction time and the efficiency of adsorption and concentration capacity were studied for various sorbents. This work has been also focused on the electrochemical detection of quantum dots for labelling the influenza virus, and also to detection the presence of a metal-binding protein lactoferrin. Electrochemical detection of quantum dots and lactoferrin was performed using a glassy carbon electrode. Detection of silver ions on different carbon paste electrodes was another aim of this work and the obtained results were used to study the antimicrobial effect of encapsulated silver ions to the bacterial culture Staphylococcus aureus.
49

Vliv kyseliny askorbové na senzorické a analytické parametry bílých vín

Smrčka, Jakub January 2015 (has links)
This thesis was focused on the effect of ascorbic acid on sensory and analytical parameters of white wine during production technology. The theoretical part is devoted to a detailed description of the mechanisms of oxidation of ascorbic acid and ultimate degradation products of ascorbic acid. In the theoretical part are also given basic methods for the determination of ascorbic acid. Another part focuses on the synergy of ascorbic acid and one of the most important substances in the manufacture of wine, sul-fur dioxide. The practical part includes an attempt was founded in 2014. The study compared different doses of ascorbic acid and sulfur dioxide have been added to the mash two varieties, Riesling and Grüner Veltliner. Attempt monitors antioxidant properties of ascorbic acid and its influence on the analytical and sensory component of the resulting wines. Based on the results, we can conclude that ascorbic acid has antioxidant capabilities asking if it was properly supplemented with sulfur dioxide.
50

Vliv síření na vznik sloučenin vázajících SO2 ve víně

Holka, Andrej January 2015 (has links)
The thesis focuse on the effect of dose levels of sulfur dioxide in the must on the formation of carbonyl compounds. Futhermore it is concerned with oenological properties of sulfur dioxide, its forms and effects on wine. The thesis corroborates in detail carbonyl compounds bind sulfur dioxide and discusses their origin and various options to affect their quantity. Substances that may partially replace sulfur dioxide and thereby reduce its total quantity in wine are also debated. Experimental part of the thesis involved samples of wine differing in quantity of sulfur dioxide added to the must before fermentation and in forms of nutrition. Using the HPLC analysis concentrations of acetaldehyde, pyruvic acid, and 2-oxoglutaric acid were determined. The experiment demonstrated the effect of initial doses of sulfur dioxide on the amount of generated acetaldehyde and pyruvic acid. The effect of addition of thiamine, which reduces formation of pyruvic acid, was also shown.

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