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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.
11

Interakce tekutého kovu s formovací směsí / Interaction between liquid metal and foundry mixture

Tomek, Ladislav January 2008 (has links)
Subject of the diploma thesis was to resolve influence of grey cast iron on penetration into cement sand. Methodology of trial was designed and its attestation was implemented in experimental and running conditions. On boundary-line cement sand and pouring metal was certified generation of complex allied substances. Created mathematical model of mechanical penetration proved influence of temperature and chemical composition of grey cast iron on range of penetration.
12

Světový trh FTTx připojení / Global FTTx market

Beníšek, Jan January 2009 (has links)
This master thesis focuses on the worldwide optical connection situation.Within the respective regions of Asia-Pacific,the Americas and Europe, it identifies the main countries and focuses on the situation and share of FTTx subscribers in them.It tries to answer the question of what technologies are represented the most on particular markets. Within each country,two service providers are chosen and their offer analyzed.For an overview,the price offer for an Internet connection with the highest transmission rate and the price for VoIP service are provided. The analytical part uses the obtained data from individual countries and regions for a price comparison and market forecast.The price comparison deals with the price level of a standard connection in relation to GDP per capita in PPS.This comparison enables the discovery of how expensive the Internet connection via FTTx is in a particular country.Furthermore, the analytical part, in relevant countries, focuses on the calculation of the ratio of costs for the yearly use of a FTTx subscription in relation to the disposable family income. The highest ratio-8.37%-was recorded in India. The thesis also includes a market forecast in the horizon of the end of 2009 and 2010 for the most important countries.For each country,the main growth factor is identified and subsequently the development for the entire year 2009 and 2010 is forecast.The worldwide forecast is 61.37 million (as of the end of 2009) and 72.67 million (as of the end of 2010) FTTx subscriptions.The contribution of this master thesis is the analysis of in what state of development the market of Internet optical connection is in the most important countries, with price comparisons and a market forecast constituting further contributions.
13

Penetrační vlastnosti polymerních micel na bázi hydrofobizované kyseliny hyaluronové. / The penetration features of the hydrofobized hyaluronic acid – based polymeric micelles.

Mischingerová, Monika January 2014 (has links)
The aim of this thesis was to investigate the penetration features of the hydrofobized hyaluronic acid – based polymeric micelles using Nile red as carried tracer. Furthermore, to implement basic characterization of polymeric micelles for potential cosmetic applications using Coenzyme Q10 (CoQ10) as carried substance. It was found that the size of the polymeric micelles with carried CoQ10 did not exceed 100 nm. Applied delivery systems based on hydrophobic hyaluronic acid were suitable for potential topical application. Delivery systems with Nile Red as carried tracer demonstrated excellent penetration features. We assume that delivery systems with CoQ10 will exhibit similar penetration features. An issue has appeared whether the carrier breaks or proceeds along with NR to the skin. Moreover, another experiments have been designed which could also verify the penetration features of these systems.
14

Laboratorní testování účinnosti hydroizolačních injektážních gelů v závislosti na stavu různých stavebních materiálů / Laboratory testing of hydroinsulating injection gel´s efficiency in dependence on state of various building materials

Miková, Lenka January 2015 (has links)
Nowadays the use of chemical gel injection for humid masonry provides many benefits. If we consider the financial aspects of this kind of remediation of humid masonry, we can say that this method is least expensive and time-consuming. In comparison with other remediation methods major interventions into the structure is not required, which could result in deterioration of the structural analysis of the works and the consequent need of special machinery, which subsequently increases spent effort and resources. There is also need for additional screens easily applied to walls breached by rising damp and this need is also required for research in dealing with this issue. Only a standard regulation dealing with remediation of wet masonry using chemical injection is directive WTA 4-4-04 / D – Injection of masonry against capillary moisture. From this point of view there is a clear need for further development in this area.
15

Vliv cementových forem na strukturu odlitků z litiny LKG / Influence of cement moulds on the structure of nodular iron castings

Stachovec, Ivo January 2009 (has links)
The object of the diploma thesis was to solve and to describe the influence of cement sands moulds on the structure of castings with cast iron LKG. The work was intent on watching the tendency of cement sands to the metal penetration of castings, rising of the compounds on the metal mould interface and liquid metal and accompanies elements on the shape of the graphite in the surface of casting. The study of this processes has a big theoretical and a practical meaning, for prevent and prediction of rising of the defects that are attached with unsuitable choice of sand.
16

Interakce jádro – tavenina při odlévání hlav válců z Al slitin do kovových forem / Interaction Core - Melt by Casting of Cylinder Heads from Al Alloys in Semi-Permanent Moulds

Hlavsa, Petr January 2016 (has links)
This dissertation thesis deals with interactions on the interface core - melt by casting of cylinder heads from Al alloys in semi-permanent moulds and solves a specific problem with sticky sand after decoring of a diesel cylinder head casting. It describes in detail the process of core production using the Cold-Box method and process of casting using the progressive technology Rotacast. It theoretically analyses the reaction on the interface core-melt and presents a classification of surface defects by Al castings produced by gravity casting into semi-permanent moulds. It also states the results of technological tests of binders, core mixtures and cores (Cogas analysis). By solution of a problem with sticky sand in intake and exhaust ports of diesel cylinder head casting is used methodology for problem solving DMAIC. All experimental tests are solved in laboratory and production conditions of an international company dealing with casting of cylinder heads from Al alloys in semi-permanent moulds.
17

Využití rychle reagujícího SBS polymeru při výrobě asfaltových směsí / Usage of fast-reacting SBS polymer in the production of asphalt mixtures

Dohnálek, Jakub January 2022 (has links)
The subject of this diploma thesis is a research of bituminous binder modification by fast react-ing polymer SBS. The theoretical part covers an introduction to bituminous binders, their pro-duction, chemical and physical-mechanical properties. The identification of bituminous binders and their use in bituminous mixtures is briefly described. To conclude, current modification methods are described in detail and important modifiers are introduced. In the practical part, three applied tests (softening point, elastic recovery and penetration) are described in detail. The bituminous binders tested (20/30, 30/45, 70/100, PMB 25/55-55 and PMB 45/80-50) and the fast-reacting polymer SBS are introduced. Samples with two weight percentages of SBS, 7,5% and 10%, are produced. Two mixing times, 60 seconds and 600 seconds were used to mix the bituminous binder and SBS. In conclusion, the results are evaluated and commented. Further research suggestions regarding this field are recommended.
18

Perorální infekce ptáků a savců neuropatogenní motolicí Trichobilharzia regenti / Peroral infections of birds and mammals with the neuropathogenic fluke Trichobilharzia regenti

Pech, Václav January 2013 (has links)
Migration within the body of an infected host is one of the most important parts in the life cycle of flukes, including schistosomes. Migration of avian and mammalian visceral schistosomes has been a quite well studied topic (Haas a Haeberlein, 2009), which became more attractive after the discovery of T. regenti, an avian schistosome which is able to migrate through the nervous tissues of infected birds and mammals as well. Migration of T. regenti and T. szidati schistosomula within the definitive (duck) and the accidental (mouse) hosts is the main topic of the diploma thesis. This work continues with the research of K. Blažová (Faculty of Science, Charles University in Prague) who studied migration of T. regenti within the definitive hosts infected perorally with cercariae or hepatopancreases of the infected intermediate snail, Radix lagotis (unpblished). She proved that T. regenti schistosomula are able to use the central nervous system for migration to the nasal mucosa of infected birds. In our work, we focused on the early phase of migration within the perorally infected birds and mice. Invasion of esophagus by T. regenti cercariae in vitro is not conditioned by secretion of glandular products, including cathepsin B2 of T. regenti (TrCB2). Activity of TrCB2 against mucins, the main components...
19

Návrhy asfaltových směsí s využitím vyššího obsahu R-materiálu / Design of asphalt mixtures with the use of higher amount of RAP

Pavličík, Petr January 2013 (has links)
In the introduction of the Master’s thesis describes for obtaining and processing of reclaimed asphlalt. Major point of the thesis is design of asphalt mixtures with use of higher amount of RAP for asphalt binder course. Asphalt mixtures were designed with contents of 0%, 30%, 50% and 70% of RAP. On each asphalt mixtures were compared parameters set out by functional tests – resistence to permanent deformation and resistence to water.
20

Reologické vlastnosti asfaltových pojiv / Rheological properties of binders

Hotař, Petr January 2014 (has links)
The comparison of rheological properties (complex shear modulus and phase angle and dynamic viscosity) of four paving bitumens and two polymer modified bitumens is performed in this diploma thesis. Furthermore, the empirical tests (needle penetration and softening point) were determined on these binders. Effect of asphalt binders aging was modeled using RTFOT test and modified RTFOT test (3 x RTFOT).

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