National Repository of Grey Literature 54 records found  beginprevious45 - 54  jump to record: Search took 0.01 seconds. 
The occurence of Cadmium in environment
Bělohlávková Staffová, Petra ; Řezáčová, Veronika (referee) ; Sommer, Lumír (advisor)
Heavy metals, including cadmium, belong to the contaminants of the environment. With permanently increasing pollution, there is an increase of these metals in the water, in the air and in the soil, which are involved in the food chain and subsequently the food of human. Cadmium has received considerable attention for its toxicological properties. Similarly, monitoring of cadmium in the Czech Republic is relatively large. There is a legislative measure regarding not only the permitted level of cadmium in the air, in the water, in the soil, but also food and is also restricted its use in the industry. Further they developed methods of its determination. In this work was devoted to attention photometric determination and some electroanalytical methods, then spectrometric methods mainly atomic absorption spectrometry and atomic emission spectrometry, which is currently the most widely used.
Determination of phosphates in waters and characterization of their negtive effects on water ecosystem
Novotný, Radek ; Komendová, Renata (referee) ; Sommer, Lumír (advisor)
This bachelor thesis is focused on the negative effects of phosphates in natural waters and their methods of determination. The first part is characterized by a negative impact on natural water and there are characterized the problems associated with eutrophication, development of cyanobacteria and algae and the resulting potential health risks. The second section describes the methods by which phosphates can be determined. The work highlights the particular spectrophotometric methods such as molybdophosphoric acid, vanadomolybdophosphoric acid, wolframophosphoric acid, phosphomolybdenum blue and methods with some basic dyes such as rhodamine B, rhodamine 6G, malachite green and crystal violet. There are also mentioned methods, which are used less frequently, but they are relatively sensitive, such as AAS, AES, LC-ICP-MS and next such as chromatographic, electrochemical and enzymatic methods. Finally, work mentions the possibility of using automatic techniques such as FIA or CFA, which are suitable for routine and frequent determination, often using the spectrophotometric methods, but not only these.
Emissions from transport - a new pollutants
Dvořák, Rostislav ; Sommer, Lumír (referee) ; Doležalová Weissmannová, Helena (advisor)
This work is focused on platinum group metals (Pt, Rh, Pd), their use in the automotive industry, risks associated with the occurrence of these substances in the environment, their potential impact on population health and, ultimately, the characteristics of these elements and some of their compounds as such.
The significance of platinum in the environment
Brestovská, Marta ; Holubová, Zuzana (referee) ; Sommer, Lumír (advisor)
This bachelor thesis deals with monitoring of individual platinum compounds in the environment (water, soil, air) and is also reviewing methods used for their analysis. The no less important determination of platinum in tissues and body fluids, when the platinum is used in form of a cisplatin as an anticancer drug, is also mentioned. Afterwards the anticancer drug itself or its derivatives and metabolites on the base of platinum complexes in clinical sample (urine, plasma) are determined. Mainly the ICP-AES, ICP-MS, ETA-AAS, HPLC methods are highlighted from the methods used for the determination of Pt. The on-line connection between some of these methods such as ICP-MS with HPLC or ICP-AES with HPLC seems to be useful. The spectrofotometric methods using organic and inorganic agents can also be used for the determination of platinum. These methods are mentioned here rather marginally, just for completeness. In terms of practical use they are difficultly reproducible and not very sensitive. The hydrolysis of platinum metals to form insoluble hydrated oxides makes also the determination difficult.
Chromogenic reactions of Uranium
Konečná, Markéta ; Doležalová Weissmannová, Helena (referee) ; Sommer, Lumír (advisor)
survey of reagents , selection of the best reagents pro spectrophotometry
The circulation of cobalt in the environment
Charuza, Martin ; Mládková, Zuzana (referee) ; Sommer, Lumír (advisor)
This bachelor thesis deals with importance of cobalt in the environment, especially as a component of B12 vitamin. Vitamin B12 is a complex, that is necessary for proper formation of blood corpuscules and DNA, except that affects many others procesess in the body. Cobalt forms many complex compounds, which are discussed in this work. The most common oxidation number in compounds are +II and +III. The second part describes spectrophotometric determination of cobalt with suitable reagents. There are a lot of spectrophotmetric reagents for cobalt determination in a sample. The most widely used spectrophotometric reagents for determination of cobalt are 4-(2-pyridylazo)resorcinol (PAR), 1-(2-pyridylazo)-2-naphtol (PAN), 2-(5-Brom-2-pyridylazo)-5-diethylaminophenol (5-Brom-PADAP), 4-(2-thiazolylazo)resorcinol (TAR) a 2-(2-thiazolylazo)-4-methoxyphenol (TAMP). All of theese reagents are heterocyclic azodyes. Cobalt is bonded on this azodyes by coordination covalent bond and forms stable complex.
Chromium and chromium species cycle in environment
Nevrlá, Jana ; Sommer, Lumír (referee) ; Dočekalová, Hana (advisor)
This work focuses in the first theoretical part mainly on the possibility of entering various forms of chromium into the environment, their accumulation and transformation in environmental compartments. There are also described methods of sampling for analytical determination of chromium, the type of treatment of these samples and the most analytical methodologies for the determination of chromium in the oxidation stage III and VI. The experimental part is focused on the quantitative determination of Cr(III) and Cr(VI) in waste water, taken from the neutralizatoin station of the Chemical faculty of Brno University of Technology, by using selected spectrophotometric methods and the obtained results are compared with the results of analytical determination of total chromium by atomic absorption spectrometry.
Transport of selected metals from the soil to the plants
Šilerová, Iva ; Sommer, Lumír (referee) ; Dočekalová, Hana (advisor)
This bachelor thesis focuses on the soil, contamination of selected heavy metals and transport of heavy metals from soil to plants. The entry of heavy metals, their reactions in the soil and their transport into the plant material are described here. Lead, cadmium and copper have been selected as the studied toxic metals. There are also described methods of soil sampling, sample preparation for analysis and determination of heavy metals in the sample.
Arsenic and arsenic species cycle in environment
Ševčíková, Kateřina ; Sommer, Lumír (referee) ; Dočekalová, Hana (advisor)
This bachelor thesis, based mostly on literature retrieval, deals with monitoring of individual arsenic compounds in the environment and is also reviewing methods used for their analysis. The experimental part is focused on determination of various arsenic in the Oncorhynchus mykiss tissue by HPLC-UV-HG-AFS. Obtained results showed that the arsenic was present in the tissue of the Oncorhynchus mykiss in form of arsenobetaine, which is common for fishes and other aquatic animals and is not toxic even for consuments.
The significance of heterocyclic azodyes for the spectrophotometry of elements
Vítková, Libuše ; Řezáčová, Veronika (referee) ; Sommer, Lumír (advisor)
Characterization of most important azodyes, structure of complex being formed during the reaction, characteristics of reacting ions of elements, significance of the reagents for spectrophotometry

National Repository of Grey Literature : 54 records found   beginprevious45 - 54  jump to record:
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