Spelling suggestions: "subject:"povrchová"" "subject:"povrchu""
21 |
Znečištění vnášené do CHKO Moravský kras povrchovými toky / Pollution entering the Moravian Karst via surface streamsVaculíková, Klára January 2020 (has links)
The Diploma Thesis deals with the water pollution entering the Protected Landscape Area Moravian Karst via surface streams. In order to quantify the extent of the pollution surface streams entering the Moravian Karst were selected. A survey of a region of interest was done. Actual volume flow rate, measurements of physicochemical parameters, water samplings, laboratory analyses of samples were done monthly from April to November 2019. Conductivity, pH, temperature, oxidation-reduction potential, concentration of dissolved oxygen, and oxygen saturation were measured in situ. Afterwards, COD, BOD, phosphate, total phosphorus, ammonia, nitrites, nitrates and Kjeldahl nitrogen were determined in the laboratory. Organic nitrogen and total nitrogen were also calculated. The results were evaluated with a respect of Government Decree No. 401/2015 Coll. Material flows were calculated for selected parameters and used as other criterion that evaluate the water pollution of monitoring surface streams. Areas out of the PLA needing an enhanced protection of watercourses were proposed based on quantified pollution. Cooperation with two primary schools in the Moravian Karst supported the research. Pupils and their teachers were trained, and they measured phosphate in surface streams from April to November 2019. The website related to phosphorus in surface water were created and results of phosphate measurement were uploaded there.
|
22 |
Studium reakcí kyslíku a ozónu na povrchu konstrukčních materiálů / Study of oxygen and ozone reactions on the surface of construction materialsKrzyžanková, Anežka January 2021 (has links)
This master's thesis deals with the study of the reactions of the ozone and oxygen with various construction materials. Ozone as an unstable gas tends to decompose spontaneously and this process can be accelerated by reaction with other substances. The aim of this work is to determine the course of ozone's formation and its depletion in after the contact with various substances. Ozone is widely used mainly due to its disinfecting effects. Therefore, the monitoring of these reactions is beneficial for the choosing of ozonizer's material or its accessories. The theoretical part of this work describes the important properties of the ozone, the possibilities of using this gas, various methods of its generation, the influence of gas admixtures and a temperature on its generation and decomposition, the methods of determining the concentration and surface reaction. The dependence of ozone's formation on the size of the reaction space was monitored for either the silicone and Teflon material in the experimental part of the thesis. The length of the hoses was 20-50 cm and the diameter of the inner space was 6 mm for Teflon and 7,99 mm for a silicone. Furthermore, other experiments were performed for the silicone material, where the formation of the ozone was monitored while the oxygen and argon were being used as working gases. The formation and the depletion of the ozone depending on the changes of reaction time were investigated in the third series of experiments. We worked with a ceramic material with two different inner diameters and also with a brass and a stainless steel material in this experiment. The materials were constructed as the tubes of the same length of 54 cm. The ozone generated from the oxygen was enclosed into the reaction tube and the depletion was monitored. The last experiment was focused on the monitoring of the course of ozone's formation in a quartz cuvette influenced by the reaction time and the composition of the working gas. The amount of generated ozone was determined by absorption spectrometry in the all studied cases. The ozone flowing through the system was adsorbed by the surface of the material during the discharge. A mixture of gases (the adsorbed ozone, the oxygen and the argon in various ratios) was present in the sealed reaction space. The Ozone was formed on the surface of the material. The adsorbed ozone decomposed into a molecular and an atomic oxygen. The atomic oxygen reacted with the oxygen molecule occurring in the reaction space. The reaction time leading to the biggest obtained concentration of generated ozone was determined by the experimental data. For most of the materials, the reaction time was about 6 minutes.
|
23 |
Využití spektrofotometrie pro stanovení reziduí léčiv ve vodách / Application of spectrophotometry for determination of drug residua in watersČapka, Lukáš January 2008 (has links)
Residua of pharmaceuticals represent biologically active compounds which can interfere with some purification processes in WWTP. Control laboratories of many WWTP and water works are equipped with UV-VIS spectrophotometers. Therefore, the main goal of this thesis was the elaboration of the method for the determination of selected drugs in water based on the VIS spectrophotometry.
|
24 |
KONTROLA POVRCHOVÝCH VAD BROUŠENÝCH POVRCHŮ / VERIFICATION OF SURFACE DEFCTS OF GRINDLING SURFACENovák, Martin January 2008 (has links)
This diploma is focused on analyse existing method usable for detection surface defects of grindling surface. Also suggests and practically testing new method for detection surface defects of grindling surface
|
25 |
Optimalizace povrchové úpravy elektrických přístrojů / Optimalization of surface treatment of electrical instrumentsSuchomel, Petr January 2011 (has links)
An analysis of current surface treatments used for electrical devices with a focus on the quality, durability and costs of the technologies. An overview of the surface treatments used in the specified area with a summary of parameters reached today.
|
26 |
Fotoluminiscence zesílená plazmonovými polaritony / Plasmon enhanced photoluminescenceÉdes, Zoltán January 2012 (has links)
Diplomová práce se zabývá fotoluminiscencí polovodičových materiálů zesílené plazmonovými polaritony. Je popsána základní teorie interakce mezi lokalizovanými povrchovými plazmonovými polaritony a fotoluminiscenčními látkami. Dva mechanismy, které mohou vést k fotoluminiscenci zesílené plazmonovými polaritony jsou diskutovány. Následně je popsán návrh aparatury pro měření fotoluminiscence a způsob její realizace. Funkčnost aparatury je ověřena měřením fotoluminiscenčních spekter objemového GaN, nanokrystalického Si a CdTe kvantových teček. Nakonec je zkoumána metoda přípravy vzorků sestávajících z kovových nanokuliček a fotoluminiscenčně aktívních CdTe kvantových teček.
|
27 |
Studium vlivu velikosti svazku na hloubku prokalení materiálu 42CrMo4 při laserovém kalení / The study of the spot size influence on the depth of hardening of the material 42CrMo4 during laser hardeningKříž, Daniel January 2015 (has links)
This master thesis is focused on surface hardening by using disk laser. Ten samples made of 42CrMo4 steel were hardened at varying speeds of quenching and diameter of the laser beam. The theoretical part initially describes the types of lasers. Further it describes methods of surface hardness processing such as kinds of hardening and chemical-thermal treatment, followed by description of the used material. Images of macrostructure, microstructure and compared values of hardness of single samples are evaluated in the experimental part. The thesis subsequently contains a technical-economic evaluation. Appropriate parameters for surface laser hardening are evaluated in the conclusion.
|
28 |
Povrchové kalení litiny výkonovým polovodičovým laserem / Surface hardening of cast iron by high power diode laserBezděk, Pavel January 2015 (has links)
The Master’s thesis deals with the technology of surface hardening by laser. High power diode laser is used for this purpose. Surface hardening is performed on cast iron BS 1452-77, at different speeds laser head and laser power. In introduction, the theoretical part deals with possible ways of hardening focusing on the benefits of laser hardening. There are mentioned basic parts of laser, type industrial lasers and their application in industry. The final part is mentions the using of material and methods used to evaluate samples. The practical part describes the using devices and carries out evaluation macrostructure and microstructure and evaluation of hardness depending on the distance from the surface.
|
29 |
Technologie galvanické anodizace neželezných kovů a slitin / Technology of Galvanic Anodization of Non-ferrous Materials and Its AlloysRemešová, Michaela January 2015 (has links)
The thesis is focused on the theoretical description of the technology of anodizing of aluminium, magnesium, zinc and their alloys. In this work, methods for formation of oxide layers and the used chemical processes are described in detail. The experimental part of this work deals with formation of oxide layers on aluminium, magnesium and zinc of high purity under different conditions. Oxide layers of different thicknesses were created on all three experimental materials. Aluminium was anodized in a bath of 10% H2SO4, magnesium in the bath of 1 mol/dm3 NaOH, and zinc in the bath of 0.5 mol/dm3 NaOH. Processes were carried out at laboratory temperature. On the aluminium, continuous oxide layer was formed. Furthermore rule "312" was verified, that can indicatively be used for calculating the thickness of the resulting oxide layer on the aluminium. When using lower current of 0.08 and 0.2 A for magnesium anodizing, dark colored layer was created comparing to higher current of 0.5 A. More rough appearance of the oxide layer was produced with increasing voltage. Further, it was observed for magnesium that the resulting layer comprises of two sublayers. For zinc, black colored layer was created when the voltage 20 V and current from 0.4 to 0.5 A were used. In the layer, two sublayers were also observed. For lower voltage and current (0.05 A, 0.17 V), formation of the oxide layer on the zinc does not occur, but the crystallographic etching was observed.
|
30 |
Povrchové úpravy kovů / Surface treatment of metalsHamal, Jan January 2016 (has links)
This master thesis describes design of suitable surface treatment technology to get component resistant to corrosion of conventional atmosphere. Given component has a shape of pin and is made of construction steel. At the beginning, there is a theoretical study of galvanic zinc coating and galvanic surface treatment in general. Then there is analysis of damaged galvanic zinc surface and its impact of corrosive resistance of that layer with collaboration with company KOZÁK SVITAVY. Corrosive resistance of damaged zinc layer is then compared with corrosive resistance of quality zinc layer. At the end of this thesis is technical and economic evaluation.
|
Page generated in 0.0268 seconds