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Influence of compounds produced by cyanobacteria on coagulation of humic waters
Brabenec, Tomáš ; Pivokonský, Martin (advisor) ; Benešová, Libuše (referee)
The diploma thesis investigates the coagulation of nature waters with humic substances and peptides/proteins produced by Microcystis aeruginosa during water treatment process with aluminum coagulants. It was confirmed that the efficiency of coagulation mechanism of humic substances and peptides/proteins strongly depends on the pH value, because pH value is limited factor of a charge properties of peptides/proteins, humic substances and hyrolysis products of coagulants. The optimal pH range for the coagulation of humic substances was 5- 6 and for cyanobacterial peptides/proteins 5-6.5. In both cases a charge neutralisation and an adsorption were dominant mechanism of coagulation. Optimal pH range for the coagulation of humic substances in the presence of cyanobacterial peptides/proteins was identical as well as optimal pH range of humic substances with absence of peptides/proteins (5-6) but the presence of peptides/proteins positively influenced particle coagulation of humic substances, because the optimal concentration of the coagulants decreased to more than half. An interaction between humic substances and peptides/proteins was demonstrated. A positive effect of coagulation was observed in the case of jar tests with absence of coagulants at a very low pH range (<4). Keywords Humic substances; AOM...
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Use of polymers for drinking water treatment
Filipenská, Monika ; Benešová, Libuše (advisor) ; Pivokonský, Martin (referee)
Sources of drinking water are limited. It is clear that the need for quality drinking water is rising. Therefore, it is necessary to continuously improve methods to ensure sufficient quantity sanitary water. Coagulation-flocculation process is very often used in drinking water treatment. Except drinking water supply is coagulation used in waste treatment to wastewaters, landfill leachate and other contaminated water. Coagulation is mediated by coagulants - they have the ability to suppress the repulsive forces between the particles so that they can join in a contact in larger particles called flocs. Large and compact flocs are easily separated from the treated water. For this purpose have been used inorganic salt for long time. Most commonly salts of aluminum and iron. However, their effectiveness is not sufficient and their use also brings other disadvantages. By using aluminum compounds also discouraged, because aluminum may have link with Alzheimer's disease. Therefore, there were developed new coagulants based on organic polymers. These polykoagulants are significantly more efficient in cleaning. Their properties are easily influence by the content of their substances. For the water treatment used them much smaller dose than inorganic coagulants and so there is even less sludge and reduce...
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Removal of microcystins during drinking water treatment
Vaněčková, Hana ; Pivokonský, Martin (advisor) ; Pumann, Petr (referee)
The aim of this diploma thesis is to explore the coagulation phase in water treatment process from two perspectives, the removal of cyanotoxin microcystin and the responses of ecotoxicological indicator species Daphnia magna to different concentration of this toxin, contained in a sample of cyanobacterial water bloom, which was extracted from a dam and was dominated by cyanobacteria Microcystis aeruginosa. The sample was administered in three environmentally relevant concentrations to 6 clones of Daphnia magna, 3 of which had previous experience with M. aeruginosa. Coagulation process was performed under optimal conditions: pH = 6.36; KNK4,5 = 0.26 mmol.l-1 ; Fe = 0.162 mg.l-1 ; DOC = 2.83 mg.l-1 using 10 ml of 0.125M NaHCO3 in two litres of ultrapure water. Individual forms of microcystin were detected in this ratio: 31.6 % MC-LR, 53.6 % MC-RR and 14.8 % MC-YR. The study has shown that under these conditions coagulation does not remove microcystin, e.g. the efficiency of the process is zero. In ecotoxicological study, with growing concentration of cyanobacterial mixture the negative impact on Daphnia magna increased. We have found interclonal variability in responses of D. magna, however, the previous experience with M. aeruginosa had no effect. With growing concentration of cyanobacterial water...
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Interactions between proteins and humic substances during coagulation
Novotná, Kateřina ; Pivokonský, Martin (advisor) ; Janda, Václav (referee)
This diploma thesis is focused on coagulation of humic substances (HS) and BSA (Bovine Serum Albumin) protein which was chosen as a representative of proteins contained in AOM (Algal Organic Matter). Additionally, possible interactions between these compounds were also investigated. It was found that the optimal dosage of coagulant is much higher for HS compared to BSA. The best removal of both HS and BSA was reached in slightly acidic pH range and it is attributed mainly to charge neutralization and adsorption mechanisms. The maximum removal rate was 70 % for humic substances and 80 % for BSA. The results show that BSA has a positive effect on coagulation of HS (resulting in a lower coagulant demand) and vice versa while BSA was removed more efficiently than HS. The existence of interactions between BSA and humic substantces during coagulation was demonstrated in certain pH ranges and it can occur even without the presence of coagulant. These interactions are highly dependent on pH that determines charge properties (and hence reactivity) of organic matters. Finally, the comparison of BSA and cyanobacterial proteins shows that their behavior during coagulation is similar. Consequently, BSA can be used as a model compound representing AOM proteins, especially their high molecular weight fraction....
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Optimization of kaoline flocculation process
Kurťák, Marek ; Švec, Jiří (referee) ; Šoukal, František (advisor)
The bachelor thesis deals with flocculation of Karlove Vary area kaolin raw materials, their sedimentation rate and correlation of the flocculation, and sedimentation properties with composition of a particular material. The research was composed of sedimentation rate monitoring, execution of COD test, and subjecting the materials emission spectrometry with inductively coupled plasma, ion chromatography and roentgen diffraction.
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The Use of Thromboelastography in Evaluation of Coagulation in Fenmales with Physiologial or Pathological Pregnancy
Polák, Ferdinand ; Závada, Josef (advisor) ; Dyr, Jan (referee) ; Feyereisl, Jaroslav (referee)
The Use of Thromboelastography in Evaluation of Coagulation in Females with Physiological or Pathological Pregnancy MUDr. Ferdinand Polák Abstract Introduction: The target of this study was to compare thromboelastography coagulation parameters in the following three groups: a) healthy pregnant women, b) healthy non-pregnant women and c) pregnant women with pathological pregnancy and also to compare it to reference limits for the common population. If appropriate, we would propose recommendations for new reference ranges for pregnant women in their third trimester. Materials and methods: Prospective observational study, comparing, by using thromboelastography, the blood samples of 60 healthy women in their third trimester of pregnancy (group GRAV) to the samples of the control group of 43 healthy non-pregnant fertile women (group NON-GRAV) and to the samples of 50 women with pathological pregnancy (preeclampsia, fetal death) in their third trimester (group PATOL). Selective percentiles were used to determine new reference limits. Results and conclusions: We found statistically significant differences between groups GRAV and NON-GRAV. Therefore, we established, based on our results, new thromboelastography reference limits for pregnant women. Coagulation changes during pathological pregnancy are less...
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Influence of peptides/proteins produced by Microcystis aeruginosa on coagulation process
Barešová, Magdalena ; Pivokonský, Martin (advisor) ; Janda, Václav (referee)
The aim of the diploma thesis is to analyze the mechanisms involved in the coagulation of peptides and proteins contained in cellular organic matter produced by Microcystis aeruginosa, and to describe their influence on the coagulation of hydrophobic kaolin suspension. According to the results of jar tests, the coagulation effectiveness and removability of COM peptides/proteins and kaolin particles are heavily dependent on pH value which determines charge characteristics of peptides/proteins, kaolin and hydrolysis products of coagulant and therefore the prevailing mechanisms of interactions between them. Efficient coagulation and the highest removal of COM peptides and proteins were achieved in the pH range of 4-6 due to charge neutralization of peptide/protein negative surface by positively charged hydrolysis products of ferric coagulant. Peptides and proteins contributed to the coagulation of kaolin particles under the reaction conditions mentioned above, too. Charge neutralization and adsorption were found to be the dominant coagulation mechanisms under these conditions. At a low COM/Fe concentration ratio (COM/Fe < 0.33), adsorption of peptides/proteins onto ferric oxide-hydroxide particles, described as the electrostatic patch model, enabled the coagulation in the pH range of 6-8. On the...
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Anticoagulation factors of haematophagous parasites
Skipalová, Karolína ; Mikeš, Libor (advisor) ; Kolářová, Iva (referee)
2. Abstract Presence of antihaemostasis molekule is essential for the successful reception of food organisms that feed on blood. They are vasodilators, anticoagulant molecules and apyrases that break into the host hemostasis, thus blocking the whole process. This work summarizes all available information about the anticoagulant factors of haematophagous parasites. The blood sucking groups of helminths, arthropods and leeches is particularly inhibitors of serine proteases, which have their inhibitory aktivity directed primarily against thrombin and factor Xa. These are two key factors in the coagulation cascade. Factor X is the first member, where it sets the intrinsic and extrinsic coagulation pathways. At the same time it arises due to the aktive form of the protein thrombin, which is responsible for the conversion of soluble fibrinogen to insoluble fibrin, which stops bleeding. In addition to these two factors are inhibited of other members of the cascade. For example the inhibition of komplex factor VII and TF, which has been described in ticks and hookworms. Anticoagulation factors play a crucial role in the transmission of pathogens by blood from the vector into the host. The longer the blood is a liquid, the greater the chance of transmission of the pathogen.
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Aluminium fractionation in water treatment.
Houšková, Lucie ; Benešová, Libuše (advisor) ; Janečková, Lucie (referee)
Aluminium and natural organic compounds are common components of surface water in our country. Removal of these substance represents one of basic problems of water treatment. Chemical treatment process is based on particles destabilisation and aggregation. The efficiency of treatment is influenced by many chemical and physical factors (the reaction conditions, type and dosage of destabilisation reagens, reactive pH, the mean velocity gradient and the period of its duration). Common water treatment technologies are based on the reagent doeses optimisation. Properties of formed aggregates (namely their size, shape and density) and their separation capabilities are influenced by the magnitude of the velocity gradient and the period of its application. This thesis is focused on the optimisation of doses of alum - Al2(SO4)3.18 H2O and the properties of aggregation. For increasing of alkalinity the lime water was used as an alkalisation reagent. Laboratory tests were conducted by jar test using the variable speed paddle gang stirrer. The result showes that Al2(SO4)3.18 H2O is suitable destabilisation reagens, but salts of the Fe3+ ionts are better.
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Removal of Selected Components from the Aquatic Environment by Coagulation Process
Měřínská, Zuzana ; Márová, Ivana (referee) ; Janda, Václav (referee) ; Mergl, Václav (referee) ; Vávrová, Milada (advisor)
This thesis deals with coagulation treatment of surface water with content of humic matters, drug residues and turbidity. Commonly used coagulants (ferrous and aluminous sulphate) and natural biopolymer based on chitosan that not yet used in the Czech Republic had been studied. The aim of this work was to found the optimal application of chitosan in water treatment and comparison of its coagulation efficiency with standard inorganic coagulants. Theoretical part of the thesis contains occurrence, classification, composition, properties and importance of humic matters and drug residues and furthermore properties of chitosan and its using in water treatment. Experimental part summarizes the obtained results from the laboratory coagulation tests with inorganic coagulants and with chitosan leading to determination of its optimal dose. Other coagulation experiments were focused on finding the possibilities of combine the two coagulants (ferrous sulphate and chitosan) and to find their optimum doses and suitable ratio. The influence of pH on water treatment with using coagulation was also studied.
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