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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
211

Využití separačních metod pro studium biologicky aktivních látek ve vodách / The Usage of Separation Methods for Research of Biologically Active Substances in Waters

Vydrová, Lucie January 2011 (has links)
Pharmaceuticals are biological active compounds with different functional groups, physico-chemical and biological properties. These chemical compounds are called as “new contaminants” which cumulate in various environmental components. These contaminants input to environment from industrial processes, hospitals and health care institutions or household sources and these pollutants can to negatively interact with environmental components. Pharmaceuticals are separated according to structure and their effects to live organisms. On the basis of drug consumption in Czech Republic the non-steroidal anti-inflammatory drugs are the most using pharmaceuticals, because these drugs can be obtain without prescriptions. The choosing analgesics for study were monitored in waste water from waste waters treatment plant (WWTP Brno – Modřice) and in surface water from two sampling sites of river Kretinka. Pharmaceuticals were monitored in surface waters in Czech Republic, in Scotland (river Thurso) and in Taiwan (river Erren, Agongdian, Yanshuei and canal of Tainan) Solid phase extraction (SPE) is used for extraction of study pharmaceutical from water system. The high performance liquid chromatography (HPLC) with diode array detection or mass spectrometry was used for determination of drugs in surface waters from Czech Republic. The water samples from Scotland and Taiwan were analysed and the high performance liquid chromatography with mass spectrometry (HPLC/MS) was used for determination of pharmaceuticals. The method of HPLC/MS enables the determination of study compounds in the very low range of concentrations (ng ? l-1). All monitored pharmaceuticals were identified and quantified in water samples from river Kretinka in Czech Republic, river Thurso (Scotland) and rivers Erren, Agongdian, Yanshuei and canal of Tainan in Taiwan and the obtained data were compared.
212

Zdravotně technické a plynovodní instalace v obytné budově / Sanitation installation and gas installation in residential building

Vaněk, Ondřej January 2016 (has links)
The thesis deals with sanitary engineering and gas installation in an apartment building with a healthcare facility. The theoretical part is focused on the installation systems, which are addressed to the suitability of the system in the given project, and the advantages and disadvantages of these systems. Computational and project part addresses the sewer, water mains and gas in the specified object. Designed building is without a basement and eight storeys. On the first floor is located technical facilities around the building and three residential units. All other floors are located on each floor of four residential units. This thesis is done on the basis of current Czech and European regulations.
213

Stanovení polárních pesticidů v odpadních a povrchových vodách / Determination of polar pesticides in waste and surface waters

Borůvková, Tereza January 2016 (has links)
This work is focused on the determination of polar pesticides in surface and waste waters. In this study Mecoprop-P, MCPA, Dichlorprop-P, 2,4-D and MCPBA in differently loaded surface waters and communal waters from sewage treatment plants were analyzed. These herbicides are included in the group identified as environmental quality standards. Some of herbicides (2,4-D and MCPA) were selected because their consumption in the Czech Republic exceeds 30 tons a year. Samples were collected prom three rivers near town of Jaroměř (Elbe, Úpa and Metuje Rivers), from one river near the town of Brno (Svratka River) and from inflow and outflow of two sewage treatment plants (WWTP Jaroměř, WWTP Brno – Modřice). Particular rivers were chosen for monitoring due to the probability of occurrence of herbicides, because they flow through agriculturally cultivated areas. Solid phase extraction (SPE) was used for the isolation of target compounds and their concentration. Gas chromatography with tandem mass spectrometry (GC/MS/MS) was used for the determination of target analytes in surface and waste waters. Selected herbicides were detected in all collected samples.
214

Využití srážkových vod ve sportovním a kulturním centru / Rainwater reuse in the sports and cultural center

Bardonová, Hedvika January 2017 (has links)
The diploma thesis is focused on rainwater reuse in the sports and cultural center and elaboration of project sanitary equipment installation. The theoretical part of the thesis is focused on performance issues rainwater reuse in the buildings. In another part of thesis are drawn calculations with three variants of the design volume storage reservoir for rain water. The drawings are part of the project.
215

Hospodaření s dešťovými vodami v komerčních objektech / Stormwater management in commercial centers

Bekmukhambetova, Nuriia Unknown Date (has links)
This diploma thesis is devoted to a rainwater management in commercial and administrative buildings. The goal of this work is to describe rainwater management system with a focus on its later usage. The work is divided into theoretical and practical parts. The first part examines the binding conditions, as well as the individual technologies and devices that must be included in the implementation of a rainwater management system. The practical part of the work is an analysis of the possibility of using rainwater for the needs of the fire brigade in Havlíčkův Brod. The result of this work is a calculation of the approximate payback period of the proposed system.
216

Mogućnost primene sintetičkog zeolita CR-100 (Crystal-Right™) za adsorpciju amonijaka iz podzemnih voda Banatskog akvifera / Possible application of synthetic zeolite CR-100(Crystal-Right™) in ammonia adsorption fromground water of Banat aquifer

Tomić Željko 29 December 2016 (has links)
<p>Uklanjanje amonijaka iz podzemnih voda u cilju dobijanja<br />pijaće vode predstavlja značajan problem, koji se do sada<br />re&scaron;avao primenom različitih postupaka. Poznato je da zeoliti<br />kao prirodni jonoizmenjivači i adsorbenti kvalitetno vezuju<br />amonijum jone u svoju alumosilikatnu matricu. Njihova<br />efektivnost, u različitim tehnolo&scaron;kim procesima, zavisi od<br />fizičko-hemijskih osobina, koje su usko povezane sa njihovim<br />geolo&scaron;kim nalazi&scaron;tima, kada se govori o prirodnim zeolitima.<br />Pored prirodnih zeolita u praksi se koriste i sintetički zeoliti<br />dobijeni raznim postupcima. Danas, je komercijalna primena<br />sintetičkih zeolita rasprostranjenija u odnosu na primenu<br />prirodnih, zbog čistoće kristalnih proizvoda i uniformne<br />veličina čestica. Crystal-Right&trade; (CR-100) je zeolit koji spada u<br />grupu najizdržljivijih proizvedenih minerala. Ovaj zeolit<br />podiže pH vrednost tretiranih voda, dok istvremeno smanjuje<br />tvrdoću i uklanjanja gvožđe i mangan. Ovo pode&scaron;avanje pH i<br />uklanjanje nepoželjnih mineralnih materija postiže se izvrsnim<br />osobinama ovog zeolita u pogledu filtriranja, ali i ispiranja<br />nakon primene.<br />Maksimalna količina adsorbovanog amonijaka iznosi 2,31 mg<br />(98%) i 2 mg (87%), iz model rastvora i uzorka podzemne,<br />bunarske vode, redno. Prisustvo drugih komponenti u<br />bunarskoj vodi uzrokuje promene u količini adsorbovanog<br />amonijaka na zeolitu. Najbolje uklanjanje postignuto je za<br />jone kalijuma već sa najmanjim masama upotrebljenog<br />zeolita. Nasuprot tome, joni kalcijuma i magnezijuma se pri<br />nižim vrednostima doziranja zeolita slabije uklanjaju iz<br />bunarske vode, dok sa porastom doziranja raste i efikasnost<br />uklanjanja na svim posmatranim temperaturama.<br />Izbor adsorpcione izoterme je pokazao da najbolje rezultate<br />daje Freundlich-ova adsorpcione izoterme, a rezultati<br />aproksimacije ukazuju na fizičku adsorpciju na heterogenoj<br />povr&scaron;ini. Negativne vrednosti entropije aktivacije upućuju na<br />zaključak da se radi o asocijativnoj adsorpciji amonijaka na<br />povr&scaron;inu zeolita, odnosno da postoji interakcija između<br />adsorbovanih molekula. Vrednosti entalpije aktivacije od<br />15,096 kJ/mol i 28,978 kJ/mol, za model rastvor i realan<br />sistem, redno, upućuju da se radi o endotermnom procesu,<br />&scaron;to i potvrđuju podaci o ravnotežnim koncentracijama na<br />različitim temperaturama.<br />Tokom eksperimenata izvedenih sa poluindustrijskom<br />kolonom ispunjenom zeolitom Crystal Right&trade; (tip CR-100)<br />potvrđena je efikasnost u uklanjanju zeolita iz bunarske vode.<br />Između ispitanih modela za određivanje kinetike u kolonskom uređaju najboljim se pokazao model Yoon-Nelson-a.<br />Koeficijent linearne korelacije za model Yoon-Nelson-a iznosi -<br />0,975, dok je koeficijent determinacije imao vrednosti 0,950.<br />Iako je model razvijen jednokomponentne sisteme pokazao<br />se kao zadovoljovajući iako se radi o realnom sistemu<br />podzemne bunarske vode koja sadrži brojne rastvorene<br />supstance, katjone zemnoalkalnih i alkalnih metala, huminske<br />kiseline, anjone itd. Može se primetiti da je postignuto<br />zadovoljavaće slaganje eksperimentalnih podataka o<br />vremenu probaja sloja (50%) sa Yoon-Nelson-ovim modelom,<br />eksperimentalno određeno vreme proboja sloja iznosi oko 59<br />časova, dok je modelom dobijeno vreme 62 časa. Konstanta<br />brzine Yoon-Nelson-ovog modela iznosi 0,051 1/h.</p> / <p>Removing ammonia from groundwater to obtain drinking<br />water is an important issue, which is so far solved using<br />different methods. It is known that zeolites as natural ion<br />exchangers and adsorbents that bind ammonium ions in its<br />aluminosilicate matrix. Their effectiveness in various<br />technological processes depends on the physical and<br />chemical properties, which are closely related to their<br />geological sites, when it comes to natural zeolites. In addition<br />to the natural zeolites in practice synthetic zeolites are used.<br />Today, the commercial application of synthetic zeolites is<br />widespread in relation to the use of natural, due to the purity<br />of crystal products and uniform particle size. Crystal-Right &trade;<br />(CR-100) is a zeolite among the most durable minerals<br />produced. This zeolite raises the pH of the treated water, while<br />the same time it reduces the hardness and remove iron and<br />manganese. This pH adjustment and removal of undesirable<br />mineral substances is achieved by the excellent characteristics<br />of the zeolite in terms of filtering, and rinsing after application.<br />The maximum amount of adsorbed ammonia at 2.31 mg<br />(98%) and 2 mg (87%), from the model solution and the<br />sample of groundwater, well water, respectively. The presence<br />of other components in the well water causes changes in the<br />amount of ammonia adsorbed on zeolite. Selection of<br />adsorption isotherms showed that the best results are<br />achieved by Freundlich&#39;s adsorption isotherm, and the results<br />indicate physical adsorption on heterogeneous surfaces.<br />Negative values of entropy of activation lead to the<br />conclusion that it is associative adsorption of ammonia on the<br />surface of the zeolite, or that there is an interaction between<br />the adsorbed molecules. The values of enthalpy of activation<br />of 15,096 kJ / mol and 28,978 kJ / mol, for the model solution<br />and real system, respectively, indicating that it is an<br />endothermic process, which is confirmed by data on the<br />equilibrium concentrations at different temperatures.<br />Experiments conducted with the pilot plant column filled with<br />zeolite Crystal Right &trade; (type CR-100) confirmed the<br />effectiveness in removing zeolite from well water. Among the<br />surveyed models to determine the kinetics of the column<br />device Yoon-Nelson&#39;s model has proven to be the best. The<br />linear correlation coefficient for the model Yoon-Nelson&#39;s is -<br />0.975, and the value of the coefficient of determination was 0.950. Although the model developed for one-component<br />systems it is proved to be satisfactory for ground water<br />ammonia adsorption. The agreement between experimental<br />data on the breakthrough point at 50% concentration (59<br />hours) with Yoon-Nelson&#39;s model, is good (62 hours). Constant<br />of Yoon-Nelson&#39;s model is 0.051 1 / h.</p>
217

Biosorpcija jona teških metala iz vode izluženim rezancima šećerne repe / Biosorption of heavy metal ions from water by sugar beet shreds

Kukić Dragana 18 November 2016 (has links)
<p>Cilj ove doktorske disertacije je bio da se ispita mogućnost primene izluţenih rezanaca &scaron;ećerne repe i njihovih tretiranih oblika, nastalih u procesu proizvodnje bioetanola, kao biosorbenata za uklanjanje jona te&scaron;kih metala iz vode. U okviru eksperimenata, u laboratorijskim uslovima izvedeni su predtretman i hidroliza izluženih rezanaca kako bi se dobili tretirani oblici, a zatim je izvr&scaron;ena karakterizacija adsorbenata, ispitane njihove adsorpcione sposobnosti, utvrđeni najbolji uslovi za njihovu primenu i ispitana mogućnost njihove vi&scaron;estruke primene u obradi vode.<br />U okviru karakterizacije materijala određen je njihov sastav, specifiĉna povr&scaron;ina i poroznost, ispitana povr&scaron;ina primenom FTIR i EDS metode i kvantifikovana količina pojedinih funkcionalnih grupa prisutnih na povr&scaron;ini primenom Boehm-ove titracije. Na osnovu FTIR metode pre i posle adsoprcije utvrđeno je koje grupe učestvuju u vezivanju jona metala.<br />Ispitan je i uticaj razliĉitih parametara na adsorpciju (vreme kontakta adsorbenta i adsorbata, veličina čestice, pH, temperatura, primenjena doza adsorbenta, jonska jačina, su&scaron;enje) radi utvrđivanja najboljih uslova za maksimalnu efikasnost.<br />Kako bi se stekao bolji uvid u sam proces adsorpcije jona na povr&scaron;inu adsorbenata, na eksperimentalne podatke primenjeni su različiti modeli adsorpcionih izotermi, a mehanizam vezivanja je detaljnije razmotren primenom kinetiĉkih modela. Primenom termodinamičkih modela utvrđena je priroda procesa.<br />Radi vi&scaron;estruke primene ovih ekolo&scaron;kih biosorbenata ispitana je i mogućnost regeneracije materijala razliĉitim kiselinama kao desorbensima i utvrđeno optimalno vreme desorpcije. Ispitana je primena kroz vi&scaron;e uzastopnih ciklusa adsorpcija &ndash; desropcija. Rezultati su pokazali da ispitani materijali imaju zadovoljavajući adsorpcioni kapacitet, ali da se mogu primenjivati i vlažni, odmah nakon procesa ekstrakcije &scaron;ećera, depektinacije i hidrolize, bez utro&scaron;ka energije za su&scaron;enje. Pored toga, utvrđeno je da se mogu regenerisati i koristiti uspe&scaron;no vi&scaron;e puta, &scaron;to otvara mogućnost za njihovu primenu u praksi.</p> / <p>The aim of this PhD thesis was to investigate the possibility of usage of sugar beet shreds and their treated forms from the bioethanol production for removal of heavy metal ions from water. In the context of experiments, pretreatment and hydrolysis of sugar beet shreds were performed in order to obtain treated forms. The characterization of biosorbents was conducted and their adsorption capacity was investigated. Also, the optimal conditions for their implementation and the possibility of their multiple applications for water treatment were determined.<br />Within the characterization of materials their composition, specific surface area and porosity were determined. The surface of biosorbents was investigated by using FTIR and EDS methods. The amount of the functional groups present on the surface was quantified by Boehm&#39;s titration. On the basis of the FTIR method before and after adsorption it was determined which functional groups participate in the binding process.<br />The influence of various parameters on the adsorption (contact time of the adsorbent and adsorbate, particle size, pH, temperature, adsorbent dose, ionic strength, drying process) were examined in order to determine the best conditions for maximum efficiency.<br />For better insight into the process of adsorption of ions on the surface of the adsorbents, different models of adsorption isotherms were applied to experimental data. Mechanism of adsorption was determined by applying different kinetic models. The nature of the process was investigated by determining thermodynamic parameters.<br />The multiple applications of these eco-friendly biosorbents was examined by regeneration investigation. The optimal time of desorption was determined and different acids were used for regeneration study. The multiple cycles adsorption &ndash; desorption was also conducted.<br />The results showed that the investigated materials have a satisfactory adsorption capacity. They can also be applied wet, immediately after the process of sugar extraction, depectination and hydrolysis, without the energy consumption for drying. In addition, it was found that they can be regenerated and successfully used several times. This opens up the possibility for their practical application.</p>
218

Vývoj hladin a přítoků do lomu Střeleč: interpretace vývoje kanálů v okolí lomu / Development of groundwater surface and inflows to the Strelec quarry: interpretation of conduits development in the quarry surroundings

Světlík, Daniel January 2014 (has links)
As a result of ground water pumping in the Střeleč quarry there has been developed a depression in ground water surface during recent 30 years impacting an area of approx. 10 km2 . Due to the existence of steep hydraulic gradient in the quarry surroundings subsurface erosion occurs resulting in a development of underground channels. The biggest one developed in the years 2000 - 2002. Its length was 300 m reaching in some place the height of 17 m. During field works in the quarry in the years 2009 - 2010 the only accessible channel was mapped. In the channel two main types of cracks were discovered. On the crossing of these cracks slumping of the sandstone occurs which causes difficulties for the mining company. A hydraulic gradient higher than 5% was determined to be critical for sand transport in the channels and widening the initial conduits into channels. The channel development and releasing of static ground water reserves also influenced chemical composition of ground water emerging in the quarry. In the period of the most intensive channel development in 2001 the ratio of ground water from static reserves on the total amount pumped was 56%. Also in this period the concentration of sulphates in the ground water of the streams in the quarry decreased significantly. In the year 2010 there were...
219

Porovnání srdeční frekvence ve vodním prostředí a na suchu / Comparasion of heart rate in the aquatic environment and on land

Thiel, Dan January 2014 (has links)
Title Comparison of heart rate in the aquatic environment and on land. Purposes The aim is to determine whether the body immersed just below the surface of the water has a significant effect on the change in heart rate compared to heart rate measured on land. Methods This is a quantitative research carried out by comparing of heart rate frequency in 30 probands, which were evaluated using statistical methods. The main output of the values was Student's paired t-test. Location of probands during the measurement was lying on his back. The height of the water column was 26 cm. Results Compare the effect of 26 cm high water column compared to normal atmospheric conditions, operating while lying on the body. Indicator is measured heart rate. We found no significant change in heart rate during measurement in resting heart rate in water, compared to measurement on land, p <0.05. Key words swimming, heart rate, water, diving, heart rate in water
220

Vodní stopa kravského mléka pro dva typy hospodářství v Libereckém kraji / Water footprint of the cow milk for two types of production systems in the Liberec Region

Hojcsková, Daniela January 2016 (has links)
The water footprint is a multidimensional indicator which was created to quantify the total volume of freshwater used for various purposes. With the water footprint it is possible to determine the volume and type of water used directly and indirectly during the production in a given place and time. The data related to the water footprints of products are utilized in the evaluation of the international trade with goods, too (a concept of virtual water used for the analysis of water stress export out of the country which imports water-intensive products). The greatest amount of water is used globally in the agriculture, so the agricultural products are the ones with the highest water footprints. The focus of concern is the water footprint of an agriculture production and the aim of this work is to bring the first results regarding the water footprint of the cow milk in the Czech Republic and also to evaluate a methodology of its calculation. Two dairy farms dealing with a market production of milk from the Liberec region were chosen for the research. The farm Rváčov is oriented to an intensive milk production and on the other hand the farm Bzí is a system with mixed elements of extensive and intensive characters of the dairy production. For the comparison of the milk production effectiveness we have...

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