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Study of the content of risk elements in soils and plant material
Vlčková, Renáta ; Řezáčová, Veronika (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the study of the content of selected heavy metals (Zn, Ni, Fe, Mn) in soils and mushrooms. The flame atomic absorption spectrometry method was used to determine the heavy metal content. Fungi and soil samples were collected at 18 sites in the Jeseníky region. The concentrations of heavy metals in the mushrooms were in the range from 140–582 mg/kg Zn, 48–380 mg/kg Fe, 5–19 mg/kg Mn and 3–8 mg/kg Ni. Zinc had the highest concentration value in all mushroom species. In soils, the concentrations of heavy metals ranged from 10–72 g/kg Fe, 52–1,000 mg/kg Mn, 29–115 mg/kg Zn and 6–50 mg/kg Ni. Iron was the most abundant element in the soils. Mushrooms contamination was assessed as a health risk in the study area. However, the pollution of forest soils was assessed as satisfactory and thus the productive function of the soil is not impaired. The type of forest cover was found to have minimal effect on the chemical composition of the soils.
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Influence of Mn ionts in nickel hydroxide on behavour electrodes
Cirkovský, Jaroslav ; Vrbický, Jiří (referee) ; Sedlaříková, Marie (advisor)
The aim of my diploma thesis was to explore the influence of manganese ions put into nickel nitrate structure. The attention was focused mainly on the stabilization of nickel nitrate a modification, which could not change into b modification. The theoretical part of my thesis focused on applied materials, kinds of acumulators, basic parameters of acumulators and the description of chosen methods of measurement employed. It contained the electrodeposition, the impedance spectroscopy and the cyclic voltammetry. The task of the experimental part was to measure the effect of manganese ions put into potassium hydroxide structure. Proportions of Ni (nickel nitrate) : Mn (manganese nitrate) 10:0, 7:3, 5:5, 6:1 and 6:4 were blended for the measurement. By means of the electrodeposition, there was a thin layer of nickel hydroxide with an admixture of manganese ions from nickel nitrate and manganese nitrate dilution put on the nickel plate. After the spread of the thin layer on the nickel plate, the measurement by the method of cyclic voltammetry followed. The next task consisted in trying to add KOH (potassium hydroxide) anionic and cationic surfactant into the dilution.
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Cycling of selected metals in the environment.
Šebková, Michaela ; Diviš, Pavel (referee) ; Dočekalová, Hana (advisor)
This bachelor thesis deals with a group of selected metals (nickel, zinc, copper, cadmium and lead) in environmental components. It occupies with natural and anthropogenic inputs of metals to the atmosphere, the water und the soil and with their transport among them components. It engages too in a question of a penetration of metals to the biosphere and in their ensuant transport within the biosphere. At each metal is description of its natural sources, chemical and physical properties, inputs in environment, transport within the biosphere and positive and negative effects on living organism is described for each studied metal. The last chapter of this thesis deals with determination of selected metals in environmental components. It discribes procedures of determination from planning over sampling and processing of sample to the final determination of metals by instrumental methods.
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Nickel and its compounds
Pařízek, Ladislav ; Kábelová, Božena (referee) ; Pilátová, Ivana (advisor)
The focus of the bachelor’s thesis is searching of possible synthesis of selected compounds of the nickel. In the theoretic part are described chemical and physical properties of nickel and its compounds, which are connected with synthesis of three following compounds of nickel. The optimal procedure of preparation of nickel compounds was found in the experimental part of the bachelor.
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Manufacturing, use and properties of nickel alloys
Kejha, Richard ; Blažík, Petr (referee) ; Záděra, Antonín (advisor)
This thesis presents a literary recherche of matters concerning on industrial use of nickel aluminates, especially on refractory and incandescent alloys. In this dissertation are witten basic market brands of constructional, refractory and incandescent alloys, and then their selected representatives. There are listed the basic properties of given materials and their approximate comparison. The basic constructional materials are monel alloys based on Ni-Cu, which achieves very good mechanicl properties and excellent corrosion resistence. Refractory and incandescent materials are mostly based on Ni-Cr or Ni-Cr-Fe. Their mechanical features are very different in normal conditions and even in high operating temperatures because there are used different kinds of addition elements and their concentration. These alloys are usually additioned by elements like W, Cu, V, Al, Nb, Ti, Ta, Mo, Co, Zr, B.
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Multiphase Ti-Ni layer on Ti6Al4V substrate by local nickel alloying
Barančíková, Miriama ; Havlík, Petr (referee) ; Jan, Vít (advisor)
This bachelor's thesis comprises two main parts. The first part consists of a theoretical study on the Ti6Al4V alpha-beta titanium alloy and on the possibilities of adjusting its tribological properties. The second part deals with experimental work with the aim of improving tribological properties of Ti6Al4V by alloying nickel into its surface, creating a hard and homogeneous surface layer with superior tribological properties. In order to achieve these goals, a nickel layer was created on a Ti6Al4V substrate by electrical deposition. The layer was later melted with an electron beam, thus creating a Ti-Ni alloy. Several different parameters of the electron beam were used to create a homogeneous surface layer. This layer was then tested for its mechanical properties. The evaluation of its microstructure was conducted as well. The experiment resulted in the creation of a surface layer with hardness and tribological properties superior to the base material.
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Determination of heavy metals in soils and sediments in the region Revúce
Kováč, Lukáš ; Vávrová, Milada (referee) ; Doležalová Weissmannová, Helena (advisor)
This thesis aims to assess the extent of contamination of soil and sediment with risk metals in Jelšava. The main polluter of the environment in this area is the magnetize factory. Sampling of soils and sediments were made in three seasons. Sampling times were staggered to represent different seasons and to take into account the impact of the seasons on the obtained values of the concentrations in soil and sediment. Sampling sites were selected according according to the different distances from the factory and according to the different loading of roads. In each of the collected samples were determined concentrations of the elements copper, lead, zinc, nickel, manganese, mercury, cadmium and vanadium. Copper, lead, zinc, nickel and manganese were analyzed by atomic absorption spectrometry with atomization in a flame (F AAS), cadmium and vanadium were determined by atomic absorption spectrometry with electrothermal atomization (ET AAS). For the determination of mercury was used mercury analyzer (AMA).
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