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41.
UPORABA EKSPERIMENTALNEGA NAČRTA PRI RAZBARVANJU ODPADNIH TEKSTILNIH VOD Z NAPREDNIM OKSIDACIJSKIM H2O2/UV POSTOPKOM
Nina Gornik, 2010, diplomsko delo

Opis: Voda kot ključni sestavni del okolja predstavlja življenjski prostor velikemu številu živali in rastlin. Prav tako je tudi sestavni del vsakega živega bitja, kateremu omogoča normalno delovanje. V odpadni vodi so prisotne snovi, ki lahko ogrožajo naravno ravnotežje, zato jih je potrebno iz nje odstraniti. Eden večjih onesnaževalcev vode je tekstilna industrija, saj so tekstilne odpadne vode trenutno najkompleksnejše med vsemi odpadnimi vodami, saj poleg barvil vsebujejo še različne dodatke, ki so potrebni za izvedbo določenega procesa. Da barvila ne ostanejo predolgo v okolju, jih je potrebno primerno obdelati. Za razbarvanje tekstilnih odpadnih vod se vedno pogosteje uporabljajo napredni oksidacijski postopki AOP (Advanced Oxidation Processes), ki temeljijo na radikalski oksidaciji onesnaževala, s težnjo k popolni mineralizaciji do okolju neškodljivih produktov ali do takšnih intermediatov, ki bi jih bilo nadalje možno obdelati v bioloških procesih. Vodikov peroksid (H2O2) je najpogosteje uporabljeno oksidacijsko sredstvo. Zaradi njegove stabilnosti ga je potrebno v čisti obliki ustrezno aktivirati. Glede na vrsto uporabljenega aktivatorja, poznamo več različnih oksidacijskih postopkov razbarvanja, med njimi je tudi aktivacija s pomočjo ultravijoličnih (UV) žarkov. Po izdelavi eksperimentalnega načrta in obdelavi odpadne tekstilne vode, onesnažene z reaktivnim barvilom C. I. Reactive Blue 268, po zgoraj omenjenem postopku, smo določili najbolj optimalno koncentracijo vodikovega peroksida (H2O2), optimalen pH medija in optimalen čas trajanja izpostavljenosti UV svetlobi.
Ključne besede: odpadna tekstilna voda, napredni oksidacijski procesi, razbarvanje, reaktivna barvila, vodikov peroksid
Objavljeno: 11.10.2010; Ogledov: 2168; Prenosov: 171
.pdf Celotno besedilo (1,69 MB)

42.
USPEŠNOST PRENOSA LABORATORIJSKIH RECEPTUR PRI BARVANJU PES SUKANCEV V PROIZVODNJO
Urška Čeh, 2011, diplomsko delo

Opis: V diplomskem delu z naslovom »Uspešnost prenosa laboratorijskih receptur pri barvanju poliestrnih sukancev v proizvodnjo« smo s pomočjo CIELAB sistema za merjenje barv preučevali uspešnost prenosa laboratorijsko izdelanih receptur v proizvodno prakso. Pri tem smo uporabili dva različna in najpogosteje uporabljena poliestrna sukanca. Barvanje je tako v laboratoriju, kot v proizvodnji potekalo v kislem mediju po enokopelnem izčrpalnem postopku barvanja pri visoki temperaturi. Po končanem postopku barvanja smo pri laboratorijsko obarvanih vzorcih analizirali tudi ekološke parametre odpadne barvalne kopeli. Iz rezultatov izhaja, da je prenos receptur zahteven proces, saj na njegovo uspešnost vplivajo tako posamezni procesni parametri, globina obarvanja kot material.
Ključne besede: Poliester, poliestrni sukanec, disperzna barvila, VT postopek barvanja, barvna metrika, parametri onesnaženja.
Objavljeno: 14.03.2011; Ogledov: 1633; Prenosov: 177
.pdf Celotno besedilo (1,07 MB)

43.
INTEGRACIJA NAPREDNIH TEHNOLOGIJ ČIŠČENJA OBARVANIH ODPADNIH VOD IZ TEKSTILNE INDUSTRIJE
Nina Novak, 2011, doktorska disertacija

Opis: V doktorski disertaciji predstavljamo študijo določitve stroškovno optimalnih obratovalnih pogojev za razbarvanje in čiščenje vodne raztopine barvila C. I. Reactive Blue 268 z naprednimi procesi čiščenja. Najprej predstavljamo rezultate laboratorijskih eksperimentov in matematične modele procesov UV/H2O2 in Fe2+/H2O2. Rezultati kažejo, da lahko z uporabo metodologije odzivnih površin razvijemo ustrezna matematična modela, ki statistično zadostno opišeta odvisnost merjenih odzivov od izbranih (vplivnih) obratovalnih parametrov. Nato prikazujemo študijo optimiranja energijsko intenzivnega procesa UV/H2O2. Kot vplivne parametre smo upoštevali koncentracijo barvila, koncentracijo vodikovega peroksida, pH, čas obdelave in temperaturo. Stroške elektrike, stroške vodikovega peroksida in stroške vode za uravnavanje koncentracije barvila smo upoštevali kot relevantne obratovalne stroške. Čeprav so minimalni stroški čiščenja ocenjeni na visokih 17 €/m3, dobljeni rezultati jasno kažejo, da moramo, če želimo zagotoviti obratovalno in ekonomsko učinkovitost, proces optimirati z obeh vidikov hkrati. Ekonomsko učinkovitost lahko dodatno izboljšamo z integracijo naprednih procesov čiščenja. Kot alternative v integriranem sistemu smo upoštevali proces UV/H2O2, proces Fe2+/H2O2 in membransko filtracijo. Procesno shemo integriranega procesa in vrednosti obratovalnih parametrov, pri katerih sistem obratuje pri minimalnih stroških, smo določili s pristopom, ki temelji na matematičnem programiranju. Iz rezultatov je razvidno, da lahko z ustrezno integracijo izbranih procesov znatno znižamo povprečne stroške čiščenja. V primerjavi s procesom UV/H2O2 so ocenjeni povprečni stroški čiščenja integriranega proces približno 75 % nižji (2,4 €/m3).
Ključne besede: čiščenje odpadnih vod, tekstilna barvila, napredni oksidacijski postopki, optimiranje, matematično programiranje, metodologija odzivnih površin
Objavljeno: 24.09.2011; Ogledov: 2513; Prenosov: 227
.pdf Celotno besedilo (3,61 MB)

44.
Evaluation of analytical methods for the determination of free formaldehyde on textile substrate
Bojana Vončina, Alenka Majcen Le Marechal, Darinka Brodnjak-Vončina, 2007, izvirni znanstveni članek

Opis: Release of formaldehyde from durable press-treated fabrics is a problem for human health and safety because formaldehyde is suspected to be carcinogenic. The accuracy of the standard test method for the free formaldehyde determination, Japan Law 112, depends on the formaldehyde content of the sample. The detection of low formaldehyde contents is particularly important in fields, like children clothing, so the application of high-performance liquid chromatography was evaluated. The results obtained by the standard testmethod, Japan Law 112, where UV/Vis spectrometer was used, were compared with the results obtained by HPLC method in which separation was performed on an RP C18 column with water-methanol as a mobile phase. It was shown that the detection limit and limit of quantification were improved using the HPLC method.
Ključne besede: analizna kemija, formaldehid, določevanje formaldehida, celulozna vlakna, HPLC, UV/VIS, analytical chemistry, formaldehyde, determination of formaldehyde, cellulose fibres, HPLC, UV/VIS
Objavljeno: 31.05.2012; Ogledov: 1689; Prenosov: 61
URL Povezava na celotno besedilo

45.
Colour of polyester thread, in regard to different dyeing procedures and dye-bathsć ph
Darinka Fakin, Alenka Ojstršek, Alenka Majcen Le Marechal, 2008, objavljeni znanstveni prispevek na konferenci

Opis: The aim of the presented research was to investigate the impact of different dyeing procedures (conventional two-baths and one-bath) and dye-bathsć pH (acidic and alkaline) on the exhaustion of five disperse dyestuffs, differing in colour (yellow, red, blue, violet and black). The dyeing of polyester thread was carried-out at two concentrations (1 and 3%). The concentration of dye residual in dye-bath effluents were determined by absorbance measurement, followed by colourimetrical evaluation of dyed samples, and colour differencescalculation. The obtained results indicating superior dye exhaustion throughout alkaline one-bath procedure in comparison to conventional polyester dyeing that affect also on reduction of dyeing time, amount of dye-bath wastewaters, and energy consumption.
Ključne besede: polyester sewing, dyeing, disperse dyestruffs, colourimetry
Objavljeno: 31.05.2012; Ogledov: 857; Prenosov: 20
URL Povezava na celotno besedilo

46.
FP7 EU project AquaFit4Use - synergy of 4 industrial sectors with the goal of waste water recycling
Alenka Majcen Le Marechal, Simona Vajnhandl, Darko Golob, 2009, strokovni članek

Opis: Sustainable water use in industry is the goal of AquaFit4Use, by a cross-sectorial, integrated approach. The overall objectives are: the development and implementation of new, reliable, cost-effective technologies, tools and methods for sustainable water supply, use and discharge in the main water consuming industries in order to significantly reduce water use, mitigate environmental impact and produce and apply water qualities in accordance with industrial own specifications (fit - for - use) from all possible sources, and contributing to a far-going closure of the water cycle in a economical, sustainable and safe way while improving their product quality and process stability.
Ključne besede: waste water recycling, reduce water use, water quality, sustainable water supply
Objavljeno: 31.05.2012; Ogledov: 1709; Prenosov: 15
URL Povezava na celotno besedilo

47.
Grafting of cotton with [beta]-cyclodextrin via poly(carboxylic acid)
Bojana Vončina, Alenka Majcen Le Marechal, 2005, izvirni znanstveni članek

Opis: Cyclodextrins are cyclic oligosaccharides. Cyclodextrin molecules can form inclusion complexes with a large number of organic molecules. The properties of cyclodextrins enable them to be used in a variety of different textile applications. Cyclodextrins can act as auxiliaries in washing and dyeing processes, and they can also be fixed onto different fiber surfaces. Because of the complexing abilities of cyclodextrins, textiles with new functional properties can be prepared. Poly(carboxylic acid)s such as 1,2,3,4-butane tetracarboxylic acid (BTCA) are well-known non-formaldehyde crosslinking reagents. BTCA has four carboxylic acid groups, which can react with hydroxyl groups of cellulose and form stable ester bonds. We crosslinked -cyclodextrin molecules on hydroxyl groups of cellulose via BTCA.
Ključne besede: textile fibres, chemical modification, beta cyclodextrines, butane tetracarboxylic acid, BTCA, FTIR, host-guest systems, formaldehyde-free crosslinking reagents
Objavljeno: 01.06.2012; Ogledov: 1261; Prenosov: 33
URL Povezava na celotno besedilo

48.
Ultrasound in textile dyeing an the decolouration/mineralization of textile dyes
Simona Vajnhandl, Alenka Majcen Le Marechal, 2005, pregledni znanstveni članek

Opis: In recent decades ultrasound has established an important place in different industrial processes such as the medical field, and has started to revolutionize environmental protection. The idea of using ultrasound in textile wet processes is not a new one. On the contrary there are many reportsfrom the 1950s and 1960s describing the beneficial effects of ultrasound in textile wet processes. The aim of this paper is to review some fundamentals of ultrasound, its broad application and gather some new researchand studies regarding ultrasound application in textile wet processes,with the emphasis on textile dyeing and the decolouration/mineralization of textile wastewaters.
Ključne besede: textile industry, textile dyes, wastewater, decoloration, degradation, ultrsound
Objavljeno: 01.06.2012; Ogledov: 967; Prenosov: 26
URL Povezava na celotno besedilo

49.
50.
Case study of the sonochemical decolouration of textile azo dye Reactive Black 5
Simona Vajnhandl, Alenka Majcen Le Marechal, 2007, izvirni znanstveni članek

Opis: The decolouration and mineralization of reactive dye C.I. Reactive Black 5, a well-known representative of non-biodegradable azo dyes, by means of ultrasonic irradiation at 20, 279 and 817 kHz has been investigated with emphasis on the effect of various parameters on decolouration and degradation efficiency. Characterization of the used ultrasound systems was performed using calorimetric measurements and oxidative species monitoring using Fricke and iodine dosimeter. Experiments were carried out with low frequency probe type, and a high-frequency plate type transducer at 50, 100 and 150 W of acoustic power and within the 5-300 mgžL initial dye concentration range. Decolouration, as well as radical production, increased with increasing frequency, acoustic power, and irradiation time. Any increase in initial dye concentration results in decreased decolouration rates. Sonochemical decolouration was substantially depressed by the addition of 2-methyl-2-propanol as a radical scavenger, which suggests radical-induced reactions in the solution. Acute toxicity to marine bacteria Vibrio fischeri was tested before and after ultrasound irradiation. Under the conditions employed in this study, no toxic compounds were detected after 6 h of irradiation. Mineralization of the dye was followed by TOC measurements. Relatively low degradation efficiency (50% after 6 h of treatment) indicates that ultrasound is rather inefficient in overall degradation, when used alone.
Ključne besede: textile industry, wastewater treatment, textile dyeing, reactive dyes, azo dyes, decoloration, ultrasound, degradation, decoloration kinetics, oxidizing species
Objavljeno: 01.06.2012; Ogledov: 1258; Prenosov: 54
URL Povezava na celotno besedilo

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