National Repository of Grey Literature 248 records found  beginprevious21 - 30nextend  jump to record: Search took 0.01 seconds. 
Questions of pollutants determination in waste waters
Tandler, Ágnes ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
In this bachelor thesis of theoretical character is being solved the problem of the presence of harmful substances in waste waters. Concerning inorganic substances attention is focused to lead and cadmium and their compounds. From the wide row of harmful organic compounds are chosen surfactants, polycyclic aromated hydrocarbons and polychlorinated biphenyls. There are described their chemical properties, origin and appearance in waste waters. This work also includes their analytical determination by mobile analysis and confirmatory methods. The last chapter includes standard operating procedure of the confirmatory fotometric method of determination of anionic surfactants, which is suitable for accredited laboratories.
Application of Separation Techniques Connected with Mass Spectrometry for the Analysis of Environmentally Important Compounds
Mácová, Daniela ; Čelechovská, Olga (referee) ; Márová, Ivana (referee) ; Demnerová, Kateřina (referee) ; Čáslavský, Josef (advisor)
The identification of the hydrolysis and photodegradation products of flexible polyurethane foams (PUFs) with addition of biooriginated and biodegradable additive was the first topic of this dissertation work. Separation of polyurethane foam hydrolysis degradation products, designed for ecotoxicological tests, was managed by high-performance liquid chromatography coupled with mass spectrometry (HPLC/MS). The degradations product structure was elucidated by tandem mass spectrometry (MSn). PUF photodegradation products were obtained by exposure of materials by irradiation at 254 nm. Semi-volatile degradation products were isolated from the exposed polyurethane by n-hexane extraction; volatile compounds were collected by solid phase microextraction (SPME). Gas chromatography with mass spectrometry (GC/MS) and complete orthogonal tandem gas chromatography with mass spectrometry (GCxGC/TOF MS) was used for separation and identification of photodegradation products. The influence of the bio-filler on the character of degradation products and the possible effect of PUF degradation products on the environment was discussed at the end of this section. The determination of isoprostanes – markers of oxidative stress in tissues of beadlet anemone (Actinia equina) was the subject of the second topic. F2-isoprostanes were synthesized from the arachidonic acid. With thereby prepared isoprostanes the method of determination by liquid chromatography with tandem mass spectrometry (HPLC/MS/MS) was developed and optimized. The isoprostane isolation process from the Actinia equina tissues was optimized with solid phase extraction (SPE). The resulting methodology was used to quantify isoprostanes in tissues of anemones, which were exposed to both moderate and high temperature changes. The temperature changes were used to initiate the oxidative stress in organisms. In addition, concentration levels of unknown compounds were also monitored. These unknown compounds were extracted from tissues together with F2-isoprostanes and their identity is discussed in this dissertation work too. The possibility of using isoprostane levels in the Anthozoa tissues for the oxidative stress monitoring is discussed in the conclusion of this work.
Problems of phenols in water
Tylichová, Petra ; Čáslavský, Josef (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor`s thesis deals with the issue of phenols in the waters. The theoretical part summarises the information about the characteristics of the phenols, its use, appearance in the environment, and its effects on human health. There are described methods of determination these substance in the waters. The last chapter disserts on possible methods of eliminating the phenols from the aqueous environment with special attention paid to the adsorption method. Part of this thesis is also dedicated to the chlorinated phenols which originate from chlorination of the phenolic waters and which cause the sensory interferences of the waters. The experimental part of this thesis is dedicated to removing the phenol from a model water through the adsorption into a powdery active carbon Norit SA SUPER.
Determination of large polyaromatics in waste waters of DEZA factory
Trefilová, Daniela ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
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.
Contamination of the environment by crude oil originated fuels, its detection, remediation and prevention
Heclová, Naděžda ; Adamec, Vladimír (referee) ; Čáslavský, Josef (advisor)
This bachelor thesis focuses on crude oil-based fuels and water and soil contaminations caused by these substances. Crude oil and the process of producing fuels out of crude oil as well as the fuels themselves (car petrol and diesel oil) are characterized in the work. The thesis also describes the methods used for their detection in the environment, the decontamination processes and the ways of petroleum products leaks prevention.
Study of plasma species by mass spectroscopy
Bureš, Michal ; Čáslavský, Josef (referee) ; Čech, Vladimír (advisor)
Plasma polymer films of tetravinylsilane and mixture of tetravinylsilane and oxygen gas were deposited on silicon wafers. Oxygen gas was mixed in tetravinylsilane to improve the compatibility of thin films on glass substrates. Mass spectroscopy was employed during the cleaning of the deposition chamber to check residual gases and process gases, during plasma deposition to monitor neutral plasma species and to follow plasma stability.
Study of the selected synthetic polymer degradation products penetration into enviromental compartments
Tobiášová, Tereza ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
The subject of this thesis is the study of the degradation of polyurethanes in the weather conditions on the waste dumps and observation of the penetration of the potential degradation products into the environment.
Importance and impact of phthalates during peritoneal dialysis and current possibilities of their replacement
Nohelová, Gabriela ; Zlámalová Gargošová, Helena (referee) ; Čáslavský, Josef (advisor)
This thesis deals with the importance and influence of phthalates in peritoneal dialysis (PD) and the current possibilities of their replacement. The information about phthalates – esters of phthalic acid - was completed with focus on the most commonly used plasticizer in medical material, bis(2-ethylhexyl) phthalate (DEHP) and its effects on the human organism and the environment. The possibilities of substitution of PVC in peritoneal dialysis were searched and their advantages and disadvantages were evaluated. As the evidence of phthalates absorbed by the human body in carrying out peritoneal dialysis selected studies performed in Germany and in our country, dealing with this issue, were used. High performance liquid chromatography (HPLC) with UV detection at 224 nm or gas chromatography - mass spectrometry (GC / MS) was used here for the determination of phthalates in the blood and dialysate in peritoneal dialysis. Extraction of sample with the suitable solvent and purification of the extract predates the actual analytical determination of sample.
Question of PET bottles recyclation: Current state and perspectives
Duliková, Michaela ; Stoupalová, Michaela (referee) ; Čáslavský, Josef (advisor)
This thesis is deals with the process of recycling of PET bottles from the sorting of waste up to the using of recycled material, so-called “PET flakes“. The attention is paid mainly to the process of the physical recycling. The dry recycling process is compared with the wet recycling process from the point of view of applied technology and quality with focus on the final product (PET flakes) from the wet recycling process. As the quality is concerned, presence of blockers and polyvinyl chloride, which causes the most serious problems during recycling, is discussed. Employed technologies as well as quality requirements for spinning, producing PET strapping band, recycling by the bottle to bottle form (B2B) and other possibilities of the usage of recycled materials are also described.
Influence of the protectives against Varroa destructor on the colonies of bees and the environment
Marečková, Kateřina ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Varroa destructor contains about six different types of mites that came from Asia and spread to Europe and gradually to the entire world. In the 70‘s of the last century the mite was identified also in the Czech Republic. The danger of the Varroa destructor is that it‘s getting into the drone´s fetus, where it is closed by the bees. Herein the mite is procreated and developed. Since 1990, the number of colonies of bees in the Czech Republic has been decreased. This is because of various reasons but one of the main causes is varroa destructor. Correct treatment of bees is directed by the regulation number 2/2007 which was released by the regional administration for South Moravia. The regulation recommends the spring, summer, autumn and winter treatment of bees by the preparations M-1 AER, FORMIDOL laminaes, GABON PA 92 and PF 90 and VARIDOL FUM and AER. All the preparations except FORMIDOL are available only on medical prescription and they are manufactured in the Bee Research Institute at Dol (Libčice nad Vltavou). This work reviews the information on the mite Varroa destructor, his origin, distribution, therapeutics and prevention. It explores the influence of the preparations used in the Czech Republic on the environment and on the bees themselves.

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