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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.
201

Stanovení těžkých polyaromátů v odpadních vodách závodu DEZA / Determination of large polyaromatics in waste waters of DEZA factory

Trefilová, Daniela January 2009 (has links)
Large polycyclic aromatic hydrocarbons with molecular mass exceeding 278 Da are rarely object of study, in spite of the fact that some compounds from this group are proved carcinogens. These compounds belong to the group of persistent organic compounds and they are considered as dangerous environmental contaminants. Diploma thesis is focused on the evaluation of the occurence of large PAHs in technological and waste waters produced in black pitch processing in the DEZA Valašské Meziříčí factory. The method of their analysis based on reversed-phase liquid chromatography with non-aqueous gradient; UV-VIS and fluorescence detection will be used. This method will enable the study of changes of large PAHs distribution at various stages of waste water treatment process.
202

Problematika produktů osobní péče ve složkách životního prostředí / Personal care products as environmental contaminants

Babuš, Ondřej January 2010 (has links)
Synthetic musk compounds were first prepared artificially in the late 19th century. They have been used to perfume cosmetics, detergents and personal care products. The attention of many researchers has been focused on it recently, due to its high penetration into the nature which is a logical consequence of its great use. The main goal of this thesis is to determine the effect of the ultrafiltration on the concentration reduction of substances mentioned above in the industrial waste waters produced by the cosmetic company. Analytes from the sample were extracted using solid phase microextraction (SPME) and on gas chromatography analysis with mass spectroscopy (GC / MS) has been performed. The whole method was optimized and evaluated. Determination of the average efficiency of the ultrafiltration was made based on data obtained before and after ultrafiltration. Such efficiency determines the suitability of use of this method for removal of synthetic musk compounds from waste waters.
203

Praktické aspekty hodnocení odpadních vod z pokovovacích procesů. / The practical aspect for evaluation of waste-water from metal plating

Válek, Roman January 2010 (has links)
The Galvanic Plating Technology is used by many branches of modern industry. Sizeable amounts of waste water are an integral part of plating technologies. It contains a versatile spectrum of chemical substances hazardous to the environment. This work focuses on monitoring the level and nature of waste water pollution resulting in primary production. Several indicators were selected to appreciate the quality of the effluent, which were defined according to the procedures. The possibility of quality monitoring process based on values of pollution was discussed after evaluating the results.
204

Hodnocení základních ukazatelů termálních vod pomocí separačních metod / Evaluation of basic characteristics of thermal water with separation methods

Skálová, Lucie January 2011 (has links)
The presence of inorganic ions is one of the criteria for thermal water assessing. The most important anions that affect the water quality and allow their use for therapeutic purposes, include sulfates, chlorides, nitrates and bicarbonates. Ions (as sodium, potassium, calcium and magnesium) are the significant cations. The ion chromatography is used for separation of these substances and also some methods based on electrophoretic migration of ions in an electric field. The electromigration method of isotachophoresis was chosen for determination of selected ions in water samples collected from thermal boreholes in Pasohlávky.
205

Stanovení mikro a makro prvků v balených vodách technikou ICP-OES / Determination of micro and macro elements in bottled water by ICP-OES technique

Herman, Vít January 2015 (has links)
This Master’s thesis deals with the determination of selected micro and macro elements in bottled water purchased in retail chains Czech Republic. There are described macro elements and micro elements that occur in the waters, bottled waters legislation and the most frequent used instrumental methods for elemental analysis. In this work for the analysis of bottled water were used methods optical emission spectrometry with inductively coupled plasma (ICP-OES) and ion chromatography (IC). Elemental composition of bottled water after analysis corresponded to the composition indicated on the labels, there were recorded only minor deviations from the reported concentrations. All bottled water meets the conditions of the legislation of the Czech Republic. The measured data were statistically processed in the XL Stat program and by multivariate data analysis was examined whether it is possible to individual bottled water from each other based on the analyzes differentiate, which can help in verifying the authenticity of bottled water and in the detection of adulteration of bottled water for profit.
206

Chladič vody pro stropní chlazení / Water chiller for ceiling cooling system

Havlíček, Jan January 2013 (has links)
The topic of this diploma thesis is to design water chiller for ceiling cooling system. The thesis is divided into four main parts. The first part deals with the theoretical description of emitting cooling systems. The following part focuses on the theory of refrigerating systems and describes especially the thermal cycle and refrigerants which are used in cooling systems. In the third chapter refrigerating equipment are described. Compressor, heat exchangers and expansion valves belong to the main parts of refrigerating systems. The final chapter is devoted to the draft and selection of components of the refrigerating system.
207

Problematika stanovení reziduí léčiv v odpadních vodách / Problems of Drug Residues Determination in Waste Waters

Lisá, Hana January 2011 (has links)
The PhD thesis deals with determination of sulfonamides and tetracyclines in waste waters. Sulphonamides and tetracyclines are widely used in human and veterinary medicine. They are biologically active compounds and block biological processes in waste water treatment plants. These substances can influence microorganisms in the environment. Sulphonamides and tetracyclines induce resistance in low concentrations. These substances penetrate into the environment from industrial production, use in households, hospitals, veterinary clinics and fish farms. Tetracyclines and sulphonamides were determined in waste water from waste water treatment plants in Brno. Optimalization of extraction of these compounds was performed by solid phase extraction. Sulphonamides and tetracyclines were determined by liquid chromatography coupled with diode array detector or coupled with mass spectrometry. Optimalized method was used for determination tetracyclines and sulphonamides in waste water from waste water treatment plants in Brno in years 2007 – 2010.
208

Možnosti mikrobiální degradace a využití odpadů z potravinářských výrob / Prospects of Microbial Degradation and Waste Utilization from Food Processing Industry

Illková, Kateřina January 2012 (has links)
This work deals with the problem of microbial degradation of the waste materials from food industry. This work is focused on the production of technological significant enzymes producing by microorganisms, which were able to use the waste as a sole carbon source. In the first part of this work, the attention was focused on the production of pectolytic enzymes. This part was made within study interships in Slovak Academy of Sciences, department of Glycomics in Bratislava. The grape pomace as the waste form winegrowing was used as a sole carbon source for microbial growth and enzymes production. The production of pectolytic enzymes was tested on this waste. After screening the most suitable microorganisms was chosen with the highest production of polygalacturonase activity. Produced enzymes were isolated by extraction techniques, purified and then identified proteomically. The aim of the second part of this work was the waste water treatment containing lipids and lipolytic enzymes. The reason was the cooperation with the company constructing grease traps. The characterization of supplied commercial preparations was the subject of this work and the other reason was the characterization of conditions for lipases secreting by microorganisms, identification of microorganisms present in the commercial preparation and testing of new microbial cultures for the development of new preparation for the grease traps.
209

Využití a účinnost kolostra v kosmetických přípravcích / The use and effectiveness of colostrum in cosmetics

Bartoňová, Klára January 2016 (has links)
This thesis deals with efficiency of colostrum contained in cosmetics. The aim of study was to determine whether the colostrum contained in cosmetic preparations have any influence on the state of human skin. The theoretical part is a literary review and it deals with defining the basic concepts and phenomena, especially the colostrum, its composition and properties. There is also discussed the raw materials used for real samples preparation and efficiency evaluated on these samples. There are also described the methods used to evaluate cosmetic products. The practical part is focused on evaluating the influence of hydratation of prepared cosmetic products. The skin hydratation and transepidermal water loss was measured by MPA 5. Consumer tests are attached to this part. Chemical stability of these cosmetics is assessed in a special chapter.
210

Barotropní oceánický slapový model / Barotropní oceánický slapový model

Einšpigel, David January 2012 (has links)
Title: Barotropic ocean tide model Author: David Einšpigel Department: Department of Geophysics Supervisor: prof. RNDr. Zdeněk Martinec, DrSc., Department of Geophysics Abstract: The main aim of this thesis is developing of a numerical model of an oceanic circulation forced by the lunisolar tidal potential. The circulation is described by the shallow water equations which are derived from the fundamental balance laws assuming that the ratio of the vertical and horizontal dimension of the investigated problem is small, which leads to the formulation of the 2- D task. Furthermore, programs for solving the shallow water equations were written. Their functionality is demonstrated on several examples. The programs include an ephemeridal tidal modul which computes the complete lunisolar tidal potential. Keywords: oceanic flow, shallow water equations, lunisolar tidal potential

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