|
|
Study of the medium influence on the pollutants sorption on microplastics
Hamplová, Marie ; Kučerík, Jiří (referee) ; Mravcová, Ludmila (advisor)
With the increasing production of plastic waste, the pollution of the environment by persistent microplastics is increasing simultaneously. Other environmental pollutants, such as various pharmaceuticals, can be sorbed on microplastics. This increases the toxicity of microplastics and their risk to living organisms. Nowadays, the use of so-called biodegradable polymers, which are supposed to degrade spontaneously, is expanding. However, their degradation can also produce microplastics. Therefore, this bachelor thesis deals with the sorption of drugs onto microplastics from biodegradable polyhydroxybutyrate (PHB) and with the influence of the surrounding aqueous environment on the rate and mechanism of sorption. Sorption of drugs onto microplastics made of synthetic polyethylene terephthalate (PET) was also carried out for comparison. The quantity of drugs was analysed by UPLC-ESI-TQ. Sorption was observed from the drug mixture for antibiotics tetracyclines. The pH value of the surrounding environment influenced the sorption rate of tetracyclines, the highest sorption occurred at acidic pH 4. According to the results of evaluation of sorption by Langmuir and Freundlich adsorption isotherms, PHB microplastics have a higher sorption capacity than PET microplastics. Therefore, PHB microplastics could be a risk for living organisms.
|
|
|
Study of the medium influence on the pollutants sorption on microplastics
Hamplová, Marie ; Kučerík, Jiří (referee) ; Mravcová, Ludmila (advisor)
With the increasing production of plastic waste, the pollution of the environment by persistent microplastics is increasing simultaneously. Other environmental pollutants, such as various pharmaceuticals, can be sorbed on microplastics. This increases the toxicity of microplastics and their risk to living organisms. Nowadays, the use of so-called biodegradable polymers, which are supposed to degrade spontaneously, is expanding. However, their degradation can also produce microplastics. Therefore, this bachelor thesis deals with the sorption of drugs onto microplastics from biodegradable polyhydroxybutyrate (PHB) and with the influence of the surrounding aqueous environment on the rate and mechanism of sorption. Sorption of drugs onto microplastics made of synthetic polyethylene terephthalate (PET) was also carried out for comparison. The quantity of drugs was analysed by UPLC-ESI-TQ. Sorption was observed from the drug mixture for antibiotics tetracyclines. The pH value of the surrounding environment influenced the sorption rate of tetracyclines, the highest sorption occurred at acidic pH 4. According to the results of evaluation of sorption by Langmuir and Freundlich adsorption isotherms, PHB microplastics have a higher sorption capacity than PET microplastics. Therefore, PHB microplastics could be a risk for living organisms.
|
|
|
Electrical properties of nanoscale heterojunctions formed between GaN and ZnO nanorods
Tiagulskyi, Stanislav ; Yatskiv, Roman ; Grym, Jan ; Schenk, Antonín ; Roesel, David ; Vaniš, Jan ; Hamplová, Marie
Vertical periodic arrays of ZnO nanorods are prepared by hydrothermal growth on GaN templates patterned by focused ion beam. Electro-physical properties of a single vertically-oriented ZnO nanorod are investigated by measuring the current-voltage characteristics using a nanoprobe in a scanning electron microscope. This technique enables to observe the surface morphology of ZnO nanorods simultaneously with their electrical characterization in vacuum. The vacuum chamber rejects the impact of gas adsorption and light irradiation, which both affect the properties of ZnO nanorods. Moreover, mechanical damage and strain induced during the nanorod transfer are eliminated. Nonlinear current-voltage characteristics under the forward bias are explained by the tunneling-recombination process and by the space charge limited current. The high reverse bias current in the p-n heterojunction is attributed to direct tunneling via a narrow tunnel barrier
|
|
|
Culture and Modification of Human Body: Female Genital Mutilation in Kurdistan
Hamplová, Marie ; Soukup, Martin (advisor) ; Soukup, Václav (referee)
The subject of the work is a theoretical and empirical analysis and interpretation of female circumcision. This distinct phenomenon is systematically analyzed with particular regard to the cultural area of Kurdistan. The work is divided into five separate chapters, and is partly based on the results of two field studies which the author carried out in Kurdistan. The aim is to contribute to the exploration of the issue of female circumcision with particular reference to Kurdistan. Keywords: Circumcision, FGM, Culture, Religion, Ritual
|
|
| |
guest ::
RSS feed.