No (313)
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313
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Light oil phase textile sorbent into remediation wells
Dimpo Alfred Molefe; vedoucí práce Jaroslav Hanuš
2012 - English
There is a great need to keep environment safe from huge threat of contaminants that are spreading at high speed above and below the ground. The main reason evolves from the dramatically increase in the usage of chemicals in many sectors and machinery where oils and fuels are demanding. This paper is based on studying the efficiency of a designed textile sorbent from nonwoven material (made from polypropylene fibers) when it is applied in light oil phase into remediation wells. The following tests were carried: capillary action tests included plain strips, tubular sorbent in oil and weight test (oil only). The absorption and capillary action include test in measuring cylinder (oil on water) and this is last test which reflects nature situation. The trip tests categorized polypropylene materials made of different nonwoven technologies and different properties according to their efficiency in absorbing oil.Two different types of sorbents were compared, completely hydrophobic ECT and ECT U that possesses both hydrophobic and hydrophilic properties. Among each of these sorbents comparison was also done, heavy (high density) against light (low density) samples. The main experimental parameters are the following: time taken for sample to reach maximum capacity, height travelled by oil during capillary action and gram oil per gram textile ratio. It was also interesting to check whether the sorbent sink at the end of experiment. The experimental results showed that ECT and ECT U heavy samples have high oil absorption capacity compared to light samples due to their better retention time. ECT U sorbents have better affinity to oil than to water. In nature simulating tests (test in measuring cylinder) absorption rate is very higher because 200ml oil is absorbed within 5-7 minutes and 396.8 ml within one hour for cylinder with 50mm diameter and 250mm long. The sorbents will not sink if used in nature.
Keywords:
znečištění podzemních vod; netkané textilie; čištění vody
Available to registered users in the Library of TUL
Light oil phase textile sorbent into remediation wells
There is a great need to keep environment safe from huge threat of contaminants that are spreading at high speed above and below the ground. The main reason evolves from the dramatically increase in ...
Carboxymethylcellulose on fibers
Nokuthula Adelaide Shezi; vedoucí práce Karolína Borůvková
2012 - English
Carboxymethylcellulose salt occurs as a white or slight yellow flocculent fiber powder or white powder which is non-toxic, tasteless, odorless and easy to dissolve. It has a thickening, emulsifying, shaping, water retention, stabilizing capacity, and becomes colourless when dissolved in cold or hot water. Carboxymethylcellulose has found a wide use in textile industry for textile surface treatment. It has gained an advantage over starch as a sizing agent for cotton yarn since it enables a smooth surface.This work discusses the use of CMC to modify the surface of polyester fibers.The topochemical modified polyester fibers are improved by the the crosslinking of polyester fibers with carboxymethylcellulose resulting in a better water absorption capacity of the polyester fibers since the polyester fibers are well known for their hydrophobic character.The overall objective of this research is to observe and determine the best crosslinking temparature and crosslinking time of the carboxymethylcellulose onto the polyester textile substrate and also to observe the maximum water absorption capacity of the treated fabric. The oven as well as the special heating vials with lids were used to perfom the whole experiments to try and accomplish the whole task of this research.
Keywords:
textilní chemie; polyestery; textilní vlákna; syntetická vlákna
Available to registered users in the Library of TUL
Carboxymethylcellulose on fibers
Carboxymethylcellulose salt occurs as a white or slight yellow flocculent fiber powder or white powder which is non-toxic, tasteless, odorless and easy to dissolve. It has a thickening, emulsifying, ...
Lamination of nonwovens with nanofibrous layer
Petros Sifiso Nkosi; vedoucí práce Jiří Chaloupek
2012 - English
The aim of this research was to develop new material using spun bond (polypropylene and polyethylene) and nanofiber materials (polyacrylonitrile) which can result to nonwoven fabric with very specific properties that are characterized by very soft and pleasant feel, excellent, comfortable properties upon contact with human skin section and higher elasticity.This research will be also setting new standards for hygienic applications (baby diapers, feminine hygiene and incontinence products). This will be a greater opportunities for bonding (polyethylene) with other fabrics for composite materials in the automotive industry or in construction.The steps that will be used to achieve all this properties .(i) The first route to achieve all this is to form bicomponent nonwoven fabric through lamination machine, where we will be laminating spunbond materials and nanofibers materials.(ii) The second route is to do tests to this samples, through controlling some parameters. First test will be comparing the penetration and efficiency for each sample using Sodium Chloride Filter instrument. The second test will be comparing the strength of joint for each sample using a tensile tester, also known as a tension test. The third and the last test will be finding the bending length to determine the flexural rigidity for each sample and compare them. The last route of this research will be using SEM analysis to show how fibers are arranged after lamination.
Keywords:
netkané textilie; textilní technologie; nanovlákna
Available to registered users in the Library of TUL
Lamination of nonwovens with nanofibrous layer
The aim of this research was to develop new material using spun bond (polypropylene and polyethylene) and nanofiber materials (polyacrylonitrile) which can result to nonwoven fabric with very specific ...
Warning clothing - study of fluorescenece fading in washing
Joyful Zamasomi Msomi; Michal Vik
2012 - English
High-visibility clothing, is a type of personal protective equipment (PPE), is any clothing worn that has highly reflective properties or a color that is easily discernible from any background. Yellow waistcoats worn by emergency services are a common example.Part of the surface of the garment may have retro reflective stripes. This way they become much more visible in the dark for observers near a light source, such as the driver of a car with its headlights on. The pattern of the retro reflecting parts also helps to distinguish between objects and people. Area reflective fabric has proven to be the most effective way of outlining the body, so that drivers can distinguish a human shape at night. For greater visibility during the daytime, very bright colors are used for the main body of the garment by means of fluorescent material. In general, people who wear high-visibility clothing are those who need to be seen during poor lighting or weather conditions, or when working in environments where there is a lot of moving machinery.Types of high-visibility clothing:There are three different classifications for high-visibility clothing:1. Class D - Outdoor daytime use only, with fluorescent or other non-retro reflective high-visibility material2. Class N - Night-time use only, with retro reflective material on a ?non-specified? background3. Class D/N - Day or night use, with a combination of fluorescent and retro reflective material.Retro reflective material reflects light back. Non-retro reflective material does not. If retro reflectiveBefore purchasing a garment, a risk assessment should be conducted to determine when and where the clothing will be worn, and what work tasks are to be completed.Environmental factors that may influence your choice of clothing include: "Temperature" Lighting and visibility (including during the day or night and different types of weather).Primary concerned regarding these garments has been the fading due to the external environmental factors as well as constant washing. This report will simply focus on fading due to washing.
Keywords:
textilní chemie; barvy; fluorescence
Available to registered users in the Library of TUL
Warning clothing - study of fluorescenece fading in washing
High-visibility clothing, is a type of personal protective equipment (PPE), is any clothing worn that has highly reflective properties or a color that is easily discernible from any background. Yellow ...
Photocatalytic properties of TiO\dindex{2} nanoparticles
Mary Immaculate sithembile dlamini; vedoucí práce Jakub Wiener
2012 - English
TiO2 is extensively used as a photocatalyst due to the strong oxidizing power of its holes, high photostability and redox selectivity. The oxymetric method was investigated for testing of photocatalytic properties of TiO2 on dye acid orange II and a saccharide to observe the influence of oxygen concentration which decreases under UV radiation. The oxymetric method was modified to test cotton and polyester samples coated with TiO2 for photocatalysis and self-cleaning properties. The findings show that there is a linear correlation between the decrease of dissolved oxygen concentration as a function of time which shows photo catalytic behavior. The kinetic model is proposed for the degradation of acid orange II which resulted in slight decolourization of the dye acid orange II. Self-cleaning property tested on cotton samples stained with red wine and coffee and exposed to solar radiation for 1 day showed some decolourization of the stains.
Keywords:
textilní chemie
Available to registered users in the Library of TUL
Photocatalytic properties of TiO\dindex{2} nanoparticles
TiO2 is extensively used as a photocatalyst due to the strong oxidizing power of its holes, high photostability and redox selectivity. The oxymetric method was investigated for testing of ...
Using of Fuzzy Technologies for Image Processing
Ondřej Kašpar; vedoucí práce Jaroslav Vlach
2012 - English
Diplomová práce se zabývá aplikací fuzzy logiky ve zpracování obrazu. Hlavním tématem práce je návrh a implementace fuzzy hranového detektoru v MATLABu a LabVIEW. Cílem práce je pak ověření efektivnosti algoritmu na obrázcích bižuterních kamenů.
Keywords:
zpracování obrazu; fuzzy logika; LabVIEW; MATLAB
Available to registered users in the Library of TUL
Using of Fuzzy Technologies for Image Processing
Diplomová práce se zabývá aplikací fuzzy logiky ve zpracování obrazu. Hlavním tématem práce je návrh a implementace fuzzy hranového detektoru v MATLABu a LabVIEW. Cílem práce je pak ověření ...
Používání mateřského a cílového jazyka učitelem v hodinách angličtiny na 2. stupni ZŠ
Lucie Škopová; vedoucí práce František Tůma
2012 - English
Cílem této bakalářské práce je vymezit hlavní principy pro používání mateřského a cílového jazyka v hodinách angličtiny a zjistit proporci používání těchto dvou jazyků vybranými učiteli ve třídách druhého stupně základních škol v Libereckém kraji. Nejdříve jsou představena teoretická východiska a jsou stanoveny situace, ve kterých učitel mluví. Poté je stručně zmíněn výzkum, který byl realizován v České republice a zabýval se tímto tématem. Dále je popsán samotný výzkum této práce a nashromážděné údaje jsou analyzovány. Výzkumný projekt byl uskutečněn ve třech různých třídách šestého ročníku základních škol, kde bylo celkově pozorováno šest hodin a celkem 1912 promluv tří různých učitelů bylo analyzováno. Na závěr jsou výsledky výzkumu představeny a diskutovány. Bylo potvrzeno, že angličtina je hlavním jazykem ve třídě. Avšak empirické výsledky se lišily od teoretického základu v otázce používání mateřského a cílového jazyka v některých specifických případech, kdy učitel mluví.
Keywords:
čeština; angličtina; jazyková výuka
Available to registered users in the Library of TUL
Používání mateřského a cílového jazyka učitelem v hodinách angličtiny na 2. stupni ZŠ
Cílem této bakalářské práce je vymezit hlavní principy pro používání mateřského a cílového jazyka v hodinách angličtiny a zjistit proporci používání těchto dvou jazyků vybranými učiteli ve třídách ...
Electrospun carbon nanoparticles/polymer composite nanofibers
Nolwazi Sanelisiwe Ngcobo; vedoucí práce Eva Košťáková
2012 - English
Polymer Nanocomposites have existed for decades now with different type of additives present in the polymer. The effect of properties depends on the scale of fillers. Nanofillers have increased within the years from nanoclays to carbon nanoparticles as well as the matrix in which they are used. The development of polymer nanocomposites is becoming more active in the area of nanomaterial because of their unique properties including optical, electrical, mechanical, thermal as well as fire retardant properties. These properties strongly depend on the mixing ratio between the organic matrix and nanofillers. Fullerenes have shown interest in the field of research due to unique chemical and physical properties that have been utilized in different fields of application in nanotechnology. The core was to focus on the mass weight of buckyballs fullerene C60 properties in polyurethane (PUR) and polyvinyl alcohol (PVA) polymer matrices to form stable polymer nanocomposites by using needleless electrospinning Nanospider? technology and rod electrospinning that would be applicable for flame retardancy material and anti-micro bacterial materials.The presence of fullerenes in polymers was investigated by thermogravimetric analysis (TGA), scanning electron microscope (SEM), Energy dispersive X-ray spectroscopy (EDS) and Raman spectroscopy. TGA results showed that the presence of C60 could enhance the thermal stability of organic polymers since organic polymers are inherently flammable. The larger the C60 level present, the better the flame retardancy of nanocomposites. Fullerenes are becoming good candidate as highly effective flame retardancy for polymeric materials by enhancing the flame retardancy properties.
Keywords:
nanokompozitní materiály; elektrostatické zvlákňování; vlastnosti materiálů; polymerní kompozitní materiály
Available to registered users in the Library of TUL
Electrospun carbon nanoparticles/polymer composite nanofibers
Polymer Nanocomposites have existed for decades now with different type of additives present in the polymer. The effect of properties depends on the scale of fillers. Nanofillers have increased within ...
Study of the roller electrospinning with regard to roller movement
Mduduzi Blessing Kumalo; vedoucí práce Oldřich Jirsák
2012 - English
The objective was to control the thickness of the layer of the polymer solution onto a spinning roller. Therefore, the effect of the angular speed of the spinning roller and viscosity of the polyvinyl alcohol solution on the thickness of the layer of the polymer solution onto a spinning roller was investigated. The concentration of the solution was kept constant while changing roller angular speed; accordingly, the roller angular speed was kept constant while varying concentration and the thickness of the layer of the polymer solution was measured, respectively. Sodium chloride was added into the solution to change viscosity of the solution.The effects of roller speed and viscosity were visually observed onto the roller surface by video camera, analyzing the number of Taylor cones. Current test was also used to analyze the spinning progress. The properties of materials, such as spinning performance and fiber diameters were analyzed.It has been concluded that the thickness of the solution layer increases when the viscosity (as a function of concentration) of the solution increases. It has been also proven that the increase in the angular speed of the spinning roller causes an increase in the thickness of the solution layer onto the roller. Throughput of the product and diameters of nanofibers are both directly proportional to angular speed of the roller and viscosity of the solution. Therefore, the thicker is the layer of the polymer solution on top of the spinning roller the improved are fabric throughput and nanofiber diameter. These work proved that adding sodium chloride into polyvinyl alcohol to change its viscosity, affect, inversely, the electrospinning progress, fabric throughput and nanofibers diameters.Finally, the researcher adds roller movement and solution rheology into the family of parameters of roller electrospinning, since it affect both the spinning progress and produced material.
Keywords:
elektrostatické zvlákňování; nanotechnologie; textilní technologie
Available to registered users in the Library of TUL
Study of the roller electrospinning with regard to roller movement
The objective was to control the thickness of the layer of the polymer solution onto a spinning roller. Therefore, the effect of the angular speed of the spinning roller and viscosity of the polyvinyl ...
Charakterizace aktivovaného kalu pomocí metod obrazové analýzy
Lukáš Valecký; vedoucí práce Lucie Křiklavová
2012 - English
Práce se zabývá návrhem automatické obrazové analýzy pro hodnocení charakteristik aktivovaného kalu z čistírny odpadních vod. Za tímto účelem bylo využito programové prostředí MATLAB a jeho knihovna Image Processing Toolbox. Vzorky aktivovaného kalu byly po dobu 3 měsíců odebírány z čistírny odpadních vod v Liberci a následně zpracovány v laboratoři pomocí klasických metod. Byly u nich stanoveny základní charakteristiky společně s nejdůležitějším parametrem - objemovým indexem kalu. Fotografie vzorků pořízené za pomoci soustavy mikroskopu a digitálního fotoaparátu byly následně automaticky analyzovány navrženým softwarem. Získaná data v podobě morfologických vlastností (činitel tvaru, fraktální dimenze, poměr stran apod.) společně s informacemi o kompozici vloček (poměr vláken a EPS vůči celkovému objemu vloček) byly porovnávány s objemovým indexem kalu za účelem nalezení základních souvislostí a vazeb. Navržená metoda analýzy obrazu může poskytnout podporu při klasifikaci nežádoucích stavů, jako je bytnění kalu, v čistírně odpadních vod.
Keywords:
software; morfologie (biologie); zpracování dat; obrazová data; počítačová analýza obrazu
Available to registered users in the Library of TUL
Charakterizace aktivovaného kalu pomocí metod obrazové analýzy
Práce se zabývá návrhem automatické obrazové analýzy pro hodnocení charakteristik aktivovaného kalu z čistírny odpadních vod. Za tímto účelem bylo využito programové prostředí MATLAB a jeho knihovna ...
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