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STUDY OF BIOGENOUS BINDERS
Cupák, Petr ; Jelínek, Petr (referee) ; Neudert, Alois (referee) ; Rusín, Karel (advisor)
oundry production, which forms an integral part of the engineering industry, is a source of waste with a negative impact on the working and living environment. The pressure on greening the production in all production branches of industry does not dodge the foundry industry and technical engineers seek out possibilities of decreasing the negative impact of the production of casting on the environment. An important source of environmentally dangerous waste in foundry operation is the use of organic compounds during the preparation of shaping and core mixtures. Their substitution with materials that would ensure similar technological features of the shaping and core mixtures as the organic materials used hitherto and at the same time decrease the amount of solid, liquid and gaseous ecologically undesirable compounds used in or arising during the preparation and use of shaping and core mixtures, would be significant for decreasing the ecological burden connected to casting production. A promising group of materials usable as components of shaping and core mixtures are the biopolymer materials which can substitute the organic connective systems used in the production of foundry cores by the means of the so-called hot processes – Hot-Box and Warm-Box. This work focuses on the exploration of the technological and ecological features of several biopolymer materials available on the domestic market which have the potential to become a full alternative of the binders used so far on the basis of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and furan resins.
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Role of benzo[a]pyrene in cancer development
Vaňátková, Petra ; Moserová, Michaela (advisor) ; Kubíčková, Božena (referee)
4 ABSTRACT Cancer is nowadays one of the most serious diseases. Tumor development is a multistage process in which the effect of internal and external factors lead to failure of regulatory and defense mechanisms of the organism and to the accumulation of mutations which are generated by these organisms. Chemical carcinogens and also biological and physical factors can be regarded as the main external factors. Polycyclic aromatic hydrocarbons are large group of chemical carcinogens. One of them, benzo[a]pyren is the most studied polycyclic aromatic hydrocarbon. Carcinogenic, mutagenic and teratogenic effects of benzo[a]pyrene had been shown on laboratory animals. Benzo[a]pyrene is considered as the main carcinogen in tobacco smoke and is connected with lung cancer development among smokers. Benzo[a]pyrene is metabolized in activation or detoxication pathways by enzymes of mixed function monooxygenase systeme of cytochromes P450. The most important enzymes involved in the activation of these compounds are CYP1A1 and CYP1B1 with cooperation of epoxide hydrolase. The reactive species generated in its activation pathway are able to form covalent adducts with DNA. The most important carcinogenic product of benzo[a]pyrene is benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide, which can caused irreversible ganges in...
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Role of benzo[a]pyrene in cancer development
Vaňátková, Petra ; Moserová, Michaela (advisor) ; Kubíčková, Božena (referee)
4 ABSTRACT Cancer is nowadays one of the most serious diseases. Tumor development is a multistage process in which the effect of internal and external factors lead to failure of regulatory and defense mechanisms of the organism and to the accumulation of mutations which are generated by these organisms. Chemical carcinogens and also biological and physical factors can be regarded as the main external factors. Polycyclic aromatic hydrocarbons are large group of chemical carcinogens. One of them, benzo[a]pyren is the most studied polycyclic aromatic hydrocarbon. Carcinogenic, mutagenic and teratogenic effects of benzo[a]pyrene had been shown on laboratory animals. Benzo[a]pyrene is considered as the main carcinogen in tobacco smoke and is connected with lung cancer development among smokers. Benzo[a]pyrene is metabolized in activation or detoxication pathways by enzymes of mixed function monooxygenase systeme of cytochromes P450. The most important enzymes involved in the activation of these compounds are CYP1A1 and CYP1B1 with cooperation of epoxide hydrolase. The reactive species generated in its activation pathway are able to form covalent adducts with DNA. The most important carcinogenic product of benzo[a]pyrene is benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide, which can caused irreversible ganges in...
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Biodegradation of polycyclic aromatic hydrocarbon in wood treated with creosote oil
Fabiánová, Tereza ; Cajthaml, Tomáš (advisor) ; Gabriel, Jiří (referee)
Wood contaminated by polycyclic aromatic hydrocarbons (PAH) represent a serious environmental risk. Composting seems to be an effective method for decontamination of such waste material. PAHs are degraded mainly under aerobic conditions the efficiency of composting could be strongly affected by the process conditions. This work is aimed at the comparison of PAH removal by a 340-days-long composting in laboratory scale composting pilots and a 240-days-long process in a pilot scale. To set up composting piles a "green substrate" commercially used for button-mushroom production and a grass substrate were used. The use of the grass substrate led to a higher PAHs removal (97% of the initial sum of PAHs) in comparison to the green substrate (81% of the initial sum of PAHs). Further, the effect of the size of wood particles on the PAHs removal efficiency was demonstrated. Analysis of phospholipid fatty acids showed an enhanced growth of gramm-negative bacteria and fungi during the composting processes. During the degradation process the enzyme activity of laccase was detected. The ecotoxicological test using a bioluminescent bacteria Vibrio fischeri and a seed germination test using seeds of Hordeum vulgare L. showed that probably no toxic products were formed during the PAHs degradation in these experiments.
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STUDY OF BIOGENOUS BINDERS
Cupák, Petr ; Jelínek, Petr (referee) ; Neudert, Alois (referee) ; Rusín, Karel (advisor)
oundry production, which forms an integral part of the engineering industry, is a source of waste with a negative impact on the working and living environment. The pressure on greening the production in all production branches of industry does not dodge the foundry industry and technical engineers seek out possibilities of decreasing the negative impact of the production of casting on the environment. An important source of environmentally dangerous waste in foundry operation is the use of organic compounds during the preparation of shaping and core mixtures. Their substitution with materials that would ensure similar technological features of the shaping and core mixtures as the organic materials used hitherto and at the same time decrease the amount of solid, liquid and gaseous ecologically undesirable compounds used in or arising during the preparation and use of shaping and core mixtures, would be significant for decreasing the ecological burden connected to casting production. A promising group of materials usable as components of shaping and core mixtures are the biopolymer materials which can substitute the organic connective systems used in the production of foundry cores by the means of the so-called hot processes – Hot-Box and Warm-Box. This work focuses on the exploration of the technological and ecological features of several biopolymer materials available on the domestic market which have the potential to become a full alternative of the binders used so far on the basis of urea-formaldehyde, melamine-formaldehyde, phenol-formaldehyde and furan resins.
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Hodnocení stavu životního prostředí: Monitoring cizorodých látek v potravních řetězcích: Hodnocení ekologických rizik vyplývajících z dat projektu, návrh následných opatření
TOCOEN, Brno ; Volka, Karel ; Holoubek, Ivan
Na 22 lokalitách byly monitorovány hodnoty kontaminace těžkými kovy (kadmium, olovo, rtuť, zinek, měď, nikl, arsen), polychlorovanými bifenyly, organochlorovými pesticidy a polyaromatickými uhlovodíky. Jsou navrhována koncepční řešení pro zajištění soustavného, kvalitního a vypovídajícího monitoringu pro hodnocení kvality životního prostředí . Zpráva obsahuje podrobné výsledky měření a přináší jejich interpretaci ve studii Stupeň kontaminace různých matric jednotlivými polutanty - hodnoceno s ohledem na časový vývoj (1996-2000) a rozdíly mezi vzorkovanými lokalitami.
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Hodnocení stavu životního prostředí: Monitoring cizorodých látek v potravních řetězcích
Česká zemědělská a potravinářská inspekce, Praha ; Český ekologický ústav, Praha ; Vysoká škola chemicko-technologická v Praze, Praha ; Volka, Karel
Zpráva obsahuje tři studie. 1. Organochlorové sloučeniny, polycyklické aromatické uhlovodíky včetně jejich derivátů a estery ftalové kyseliny v terestrickém ekosystému - Hodnocení zátěže ekosystému estery ftalové kyseliny v blízkosti bodového zdroje, 2. Standardní operační postupy - SOP pro odběr rostlinných komodit - Jablka, pšenice, brambory, slunečnice, řepka a objemná krmiva, 3. Stanovení kovů metodou isotopové zřeďovací hmotnostní spektrometrie s indukčně vázaným plastem.
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