National Repository of Grey Literature 71 records found  beginprevious47 - 56nextend  jump to record: Search took 0.00 seconds. 
Problems of plastics and microplastics in FTIR analysis of soils
Stanislavová, Veronika ; Kučerík, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
Microplastics are formed as the result of the fragmentation of plastics. The microparticles are easier to distribute and thus can contaminate the environment. Recently, there has been an increasing interest in the research of microplastics present in the soil system, using different methodologies. The focus of this thesis is the analysis of microplastics in soil using infrared spectroscopy – ATR (attenuated total reflectance) and DRIFT (diffuse reflectance) techniques. This work aimed to evaluate the suitability of the method for the identification of microplastics in soils. Polymers such as polyethylene terephthalate (PET), poly-3-hydroxybutyrate (PHB) and polylactic acid (PLA) were used. In the first part of experimental analysis were microplastics mixed in different concentrations with 3 different types of model soils. The obtained infrared spectra of samples of mixtures (model soil and plastics) were used for statistical evaluation. The second part of the measurement was focused on the monitoring of changes in the spectra of real soils spiked with PET, after exposure to the degradation. After the interpretation of infrared spectra of samples of plastics with real and model soil, it was possible to confirm the presence of the functional groups of each polymer. Based on the measurements, the used techniques were evaluated as inappropriate for the qualitative determination of PLA. The results of the experimental part confirm the accuracy of FTIR (both ATR and DRIFT) for the analysis of microplastics in soil for samples containing PET and PHB.
Study of selected antibiotics sorption on polyhydroxybutyrate
Amrichová, Anna ; Doležalová Weissmannová, Helena (referee) ; Řezáčová, Veronika (advisor)
The bachelor thesis deals with the issue of sorption of antibiotics on microplastics. Antibiotics and microplastics are now a highly studied topic, due to the positive and negative properties. Antibiotics with groups of sulfonamides and quinolones were selected for the experiment. From sulfonamides, sulfamethoxazole and trimethoprim were selected, and from the quinolones, enrofloxacin and ciprofloxacin, which have already been the impetus for some microplastic studies. Biodegradable polyhydroxybutyrate was used as the microplastic. Two experiments were performed in the laboratory. The first aimed to monitor the time dependence of antibiotic sorption on polyhydroxybutyrate, the second the concentration. The concentration dependence was subsequently evaluated using the Freundlich and Langmuir isotherms. The method of liquid chromatography with mass spectrometry was used for analyzes.
FTIR analysis of soils containing plastics and microplastics
Sinčáková, Lenka ; Pavlovský, Jiří (referee) ; Doležalová Weissmannová, Helena (advisor)
This bachelor thesis deals with the sources of microplastics in soils, their potential toxicity for men as well as the environment and soil-plastic interaction. It provides an overview of methods that are commonly used for qualitative and quantitative characterisation of microplastics in soils with focus on FTIR spectrometry. In the experimental part, real soil samples were evaluated with the use of ATR-FTIR based on model soils-microplastics mixtures calibrations. Vaidation models for model mixtures and carbon content were also evaluated.
Removal of Contaminants from Water.
Spáčilová, Markéta
This study deals with commonly used plastics; polystyrene (PS), polytetrafluorethylene (PTFE), polyamide (PA), polyethylene glycol terephthalate (PET), polyethylene (PE), etc. Microplastic samples were prepared by abrasion from commonly available plastics to simulate real microplastic occurrence in the environment. Prepared samples were characterized by scanning electron microscopy (SEM), Raman spectroscopy and infrared spectroscopy (IR) to obtain their fingerprints. These characteristics can be applied as standards for characterization of real microplastics.
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Microplastics removing from water
Ermis, Martin ; Himr, Daniel (referee) ; Štigler, Jaroslav (advisor)
This thesis deals with the occurrence of microplastics in water, the reasons for their potential elimination, and the possibilities leading to that. More specifically, it focuses on flotation as a process for removing microplastics from water. Flotation is further described from a theoretical point of view and its mathematical model is developed. The wettability of selected polymers is measured. The experiment performed to determine the efficiency of flotation as a process of treating water from microplastics is described. This efficiency is further compared to measured wettability.
Plastics and microplastics in water
Halašta, Tomáš ; Kučera, Tomáš (referee) ; Biela, Renata (advisor)
This bachelor thesis deals with the occurrence of plastics and microplastics in water and also is mainly devoted to microplastic in water treatment plants. The beginning of the work is devoted to plastics, their history, description of properties and what are the most commonly used plastics, which can be found in the form of microplastics. Next topic is devoted to the occurrence of plastics in waters, mainly seas and oceans, and especially in freshwater systems. Then the definition of microplastics and their sources and occurrence is given in the work. Furthermore, the work deals with studies on the occurrence of microplastics in drinking water and their removal at water treatment plants and the analysis of plastics microparticles. The conclusion is a summary of all available studies on microplastics in drinking water and water treatment plants.
Elimination of nanoplastics by cavitation and advanced oxidation processes
Kluknavská, Júlia ; Burda, Radim (referee) ; Rudolf, Pavel (advisor)
Táto práca sa zaoberá znečistením životného prostredia mikro a nanoplastami a ich možnou likvidáciou. Práca pozostáva z rešeršnej a experimentálnej časti. V rámci rešerše je opísaná problematika mikro a nanoplatov z hľadiska ich vzniku, disperzie do životného prostredia a živých organizmov. V závere rešeršnej časti sú opísané súčasné možnosti eliminácie mikro a nanoplastov pri čistení odpadových vôd. Súčasné riešenia sú založené prevažne na filtrácii, ktorá však zo svojej podstaty nemôže byť absolútna. Bol vyslovený predpoklad, že pomocou zariadenia CaviPlasma by bolo možné eliminovať mikro a nanoplasty z odpadových vôd. Cieľom práce bolo experimentálne overiť tento predpoklad. Skúšobnou vzorkou bola suspenzia vody a polyamidových častíc, ktorá bola následne vystavená pôsobeniu kavitácie a plazmového výboja. Pri experimente nedošlo ku zničeniu častíc a ani ich k viditeľnému porušeniu. Ukázalo sa však, že plazmový výboj môže iniciovať zhlukovanie sa častíc až do takej miery, že sú pozorovateľné kontinuálne štruktúry mikroplastov. Tento jav by mohol byť potenciálne prospešný pri zachytávaní mikročastíc filtráciou.
Fate of microplastics in soil
Kameníková, Eliška ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
The problems with microplastics, small plastic particles contaminating the environment, is a subject of heated discussions today. It has been recognized that the microplastics are not inert, but instead they have an impact on all enviromnental compartments. There are studies describing the negative effects of microplastics, for example on fauna and flora or on human health, but the effects on soil quality have not been sufficiently described. The aim of this thesis was to assess the short and medium term effects that microplastics could have on the soil. In this work, a series of experiments were performed to elucidate the fate of microplastics in the soil. Changes in soil organic matter thermal properties, soil respiration, amount of water and soil aggregation depending on the incubation time were monitored. Three types of agricultural land (chernozem, cambisol and phaeozem), which were contaminated with different concentrations od PET and tyre rubber, were tested. The results confirmed the specific effects of microplastics on soil properties, which were observed in non-incubated samples (i.e. at the time of incubation 0 months), microplastics did not behave inertly in the soil and affected, for example, soil properties, texture and respiration.
Removal of microplastics from water
Skalníková, Andrea ; Pivokonský, Martin (advisor) ; Čermáková, Lenka (referee)
The aim of this diploma thesis is to investigate the removability of microplastsic particles with different shapes (fragments, sphers, fibers) by standard water treatment process, such as coagulation, filtration and sedimentation. For the experimental purpose in this study, polyvinyl chloride with a size ≤ 50 μm and a density of 1.38 g/cm3 , was used as a representative of microplastics. The coagulation has been provided by ferric sulphate in pH range 5, 6, 7 and 8 and at a diferent dose of coagulant 20, 40, and 60 mg/l. The study results has shown, that the coagulation efficiency of polyvinyl chloride particles were affected by pH. The optimal value of pH has been 7 at the coagulant dose of 20, 40 and 60 mg/l. The presence of polyvinyl chloride shown a positive effect on coagulation. It has been reflected in a reduction of the residuals of iron concentration after coagulation, at pH 5-7. Solution with polyvinyl chloride contained 1,2 mg/l dissolved organic carbon. After fitlration the concentration decreased up to 70 % at pH 7 at dose of coagulant 40 and 60 mg/l. Experiments have shown that polyvinyl chloride particles are capable of faster sedimentation after coagulation. The flocs formed during coagulation interacted effectively with the polyvinyl chloride particles and facilitate their removal...

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