• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 1
  • 1
  • Tagged with
  • 4
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

Bakterijų, augančių ant polietileninių paviršių, atranka ir identifikavimas / The selection and identification of bacteria, growing on the polyethylenical surfaces

Vaitkevičiūtė, Alma 08 September 2009 (has links)
Darbo tikslas buvo išskirti, identifikuoti bakterijas, įvertinti jų gebėjimą įsisavinti medžiagas, sudarytas iš daug anglies (C) atomų turinčių grandinių. Iš sandėlio – šaldytuvo, nuo sūrių polietileninių paviršių buvo surinkti pavyzdžiai ir, remiantis morfologiniais požymiais buvo išskirta 12 bakterinių kamienų. Įvertinus augimo priklausomybę nuo temperatūros, galima teigti, kad bakteriniai kamienai priklauso psichrofilams. Buvo analizuojamos fiziologines savybės: ląstelės sienelės tipas, cukrų rauginimas, želatinos hidrolizė, krakmolo hidrolizė, kazeino hidrolizė, triptofano skaidymas, oksidazės ir katalazės testai. Remiantis šių testų rezultatais, atlikta klasterinė analizė, nustatytas bakterinių kamienų panašumas. Kadangi bakterijos išskirtos nuo polietileninių paviršių, buvo įvertintas jų gebėjimas įsisavinti mažai anglies (C) atomų turinčius angliavandenilius (kaip polietileno fragmentus). Nustatyta, kad visi bakteriniai kamienai įsisavina tetradekaną, heksadekaną ir dokozaną. Vadinasi, per ilgą laiko tarpą analizuojami bakteriniai kamienai gali pradėti naudoti polietileną kaip anglies šaltinį. Identifikavimui buvo pasirinktas S7 bakterinis kamienas. Atlikus S7 bakterinio kamieno identifikavimą pagal 16 S RNR geno analizę, buvo nustatyta, kad tiriamas bakterinis kamienas - Staphylococcus genties atstovas. / The aim of this work was to isolate and identify microorganisms, to estimate their ability to assimilate the substances with a lot of chains with any number of carbon (C) atoms. There were collected the samples, from the surfaces of cheese polyethylene packing in the storeroom – fridge. In accordance with their morphology there were isolated 12 bacterial strains. There was estimated the bacterial strains dependence on the temperature. I can propose, that the bacterial strains belongs to the facultative psychrophyles (psychrotrophs). There were analyzed the physiological properties of the bacterial strain: the composition of the cell wall, sugar fermentation, gelatin hydrolysis, starch hydrolysis, casein hydrolysis, tryptophan degradation, oxidase and catalase tests. According to the results of these test, there was made the clusters analysis and was determined the similarity of the bacterial strains. There was estimated the ability to assimilate hydrocarbons as the fragments of polyethylene, because the bacterial strains were isolated from the polyethylene surfaces. According to the results, there was determined that the bacterial strains assimilated the tetradecane, hexadecane and docosane. It means that after a long time these bacterial strains would start to assimilate the polyethylene as a sole carbon source. There was chose up the S7 bacterial strain for the identification. According to the results of the 16 S RNA gene analysis, there was determined that the analysed... [to full text]
2

Qualitative and Quantitative Characteristics Researches of Microorganisms in Mixed Loading Biofilter / Mikroorganimų kiekybinių ir kokybinių charakteristikų tyrimai mišrioje biofiltro įkrovoje

Žarnauskas, Lukas 17 June 2009 (has links)
In the final master’s paper problems of environment air pollution are analysed, statistical data about air pollution from stationary and mobile pollution sources are provided and air pollution by VOC in Lithuania is separately analysed. Components of biofiltering process are described in detail: loading, biofilm, microorganisms; objectives and tasks of the paper are defined. Also, analysis of experimental research data is provided, from which it was determined that the most favourable medium for the microorganism growth is the foam cube faction of bioloading mixture. Most of the colonies have grown in the 1st cassette of the biofilter. Cultures of the mould fungus and bacteria were discovered, the percentage of distribution of which was respectively 5.7% and 94.3%. Furthermore, the final master’s paper provided the description of the methodology of quantitative and qualitative characteristics of the experimental research, determination of precise number of the microorganism colonies, operation principle of the biofilter, as well the results of the experimental research. Using the biological system growth models, the data of the performed experiment (the grown microorganism colony number cfu/g) were compared to the results calculated in theory and conclusions along with suggestions were provided. The paper concludes of 6 parts: introduction; literature overview, research methodology, research results and analysis, mathematical modelling of the biological systems, general... [to full text] / Baigiamajame magistro darbe išnagrinėtos aplinkos oro taršos problemos, pateikti statistiniai duomenys apie oro taršą iš stacionarių ir mobilių taršos šaltinių ir atskirai išanalizuota oro tarša LOJ Lietuvoje. Detaliai aprašyti biofiltracijos proceso komponentai: įkrova, bioplėvelė, mikroorganizmai, apibrėžti pagrindiniai darbo tikslai ir uždaviniai. Taip pat išnagrinėti eksperimentiniai tyrimų duomenys, iš kurių nustatyta, kad palankiausia terpė mikroorganizmams augti – bioįkrovos mišinio porolono kūbelių frakcija. Daugiausiai kolonijų užaugo I biofiltro kasetėje. Aptiktos pelėsinių grybų ir bakterijų kultūros, kurių procentinis pasiskirstymas atitinkamai 5.7% ir 94.3%. Be to, baigiamajame magistro darbe aprašyta mikroorganizmų kiekybinių ir kokybinių charakteristikų eksperimentinių tyrimų metodika, tikslaus mikroorganizmų kolonijų skaičiaus nustatymas, biofiltro veikimo principas, pateikti eksperimentinių tyrimų rezultatai. Riboto ir neriboto augimo modeliais, atliktojo eksperimento duomenys (užaugusių mikroorganizmų kolonijų skaičius kfv/g) palyginti su teoriškai apskaičiuotais rezultatais, pateiktos išvados ir pasiūlymai. Darbą sudaro 6 dalys: įvadas; literatūros apžvalga; tyrimų metodika; tyrimų rezultatai ir jų analizė; biologinių sistemų matematinis modeliavimas; bendrosios išvados ir pasiūlymai bei literatūros sąrašas. Darbo apimtis – 98 p. teksto be priedų ir publikuotų straipsnių, 44 paveikslų, 7 lentelės, 35 bibliografinių šaltinių, 57 moksliniai straipsniai, 4... [toliau žr. visą tekstą]
3

Karakterizacija biodegradabilnosti naftnih ugljovodonika u zemljištu i bioremedijacionih procesa u toku tretmana biogomilama i površinskom obradom / Characterisation of the biodegradability of petroleum hydrocarbons in soil and the bioremediation processes during treatment by biopiles and landfarming

Maletić Snežana 01 June 2010 (has links)
<p>U okviru ovog istraživanja ispitani su: (1) Procesi koji se odvijaju prilikom &nbsp;bioremedijacije zemlji&scaron;ta zagađenog naftom i derivatima nafte, koje je bilo izloženo&nbsp;spontanim abiotičkim i biotičkim procesima degradacije u toku 8 godina, tehnikama&nbsp;biogomila i povr&scaron;inske obrade na poluindustrijskoj (pilot) skali uz optimizaciju&nbsp;tehnolo&scaron;kih parametara sa ciljem povećanja efikasnosti i efektivnosti biodegradacije&nbsp;ugljovodonika; (2) Uticaj starenja, koncentracije, biodsotupnosti i strukture zagađujućih&nbsp;materija na procese biodegradacije i biotransformacije u kontrolisanim laboratorijskim&nbsp;uslovima. Tokom dve godine bioremedijacionog tretmana sadržaj mineralnih ulja opao&nbsp;je za 52% (od 27,8 g/kg do 13,2 g/kg) i 53% (od &nbsp;23,2 g/kg do 10,8 g/kg), dok je sadržaj&nbsp;ukupnih ugljovodonika opao za 43% (od 41,4 g/kg do 23,4 g/kg) i 27% (od 35,3 g/kg do&nbsp;25,8 g/kg) u biogomili i povr&scaron;inskoj obradi respektivno. Efikasnost uklanjanja&nbsp;mineralnih ulja iz zemlji&scaron;ta u dva posmatrana bioremedijaciona tretmana je praktično&nbsp;ista. Međutim, u pogledu sadržaja ukupnih ugljovodonika u biogomili uklonjeno je dva&nbsp;puta vi&scaron;e ukupnih ugljovodonika (gledajući &nbsp;apsolutnu količinu ukupno uklonjenih&nbsp;ugljovodonika). Kinetika biodegradacije mineralnih ulja i ukupnih ugljovodonika u toku&nbsp;tretmana u biogomili u saglasnosti je sa kinetičkim modelima lnC=lnC<sub>0-</sub>kt i lnC=lnC<sub>0-</sub>kt<sup>0,5</sup>. Kinetika biodegradacije mineralnih ulja u toku povr&scaron;inske obrade relativno se&nbsp;dobro može opisati sa dva pomenuta kinetička modela, međutim, znatno bolju&nbsp;korelaciju pokazao je linearni model (C=C<sub>0-</sub>kt) primenjen na prvih 92 i poslednjih 200&nbsp;dana eksperimenta. Promena sadržaja ukupnih ugljovodonika u toku povr&scaron;inske obrade&nbsp;zagađenog zemlji&scaron;ta relativno je u dobroj korelaciji samo sa kinetičkim modelom&nbsp;lnC=lnC<sub>0-</sub>kt<sup>0,5</sup>. Laboratorijska ispitivanja pokazala su da biodegradabilnost i sudbina&nbsp;ugljovodonika u životnoj sredini jako zavise od tipa, starosti i koncentracije zagađujućih&nbsp;materija. Naime, u slučaju zemlji&scaron;ta sveže kontaminiranog dizel uljem, već pri&nbsp;<br />koncentracijama od 20 mg/g uočen toksičan efekat koji je prevaziđen nakon dve nedelje&nbsp;tretmana kao posledica smenjenja prekomerne koncentracije rastvorenih ugljovodonika&nbsp;biotičkim i abiotičkim putem i adaptacije prisutne mikroflore. U slučaju većih&nbsp;koncentracija ovaj efekat je bio jo&scaron; izraženiji. Kod zemlji&scaron;ta kontaminiranog sirovom&nbsp;naftom isti efekat se javlja tek pri koncentraciji od 35 mg/g, kao posledica toga da&nbsp;sirova nafta sadrži manju količinu lako rastvornih ugljovodonika. Za razliku od sveže&nbsp;kontaminiranog zemlji&scaron;ta, na biodegradaciju starog naftnog zagađanja u zemlji&scaron;tu&nbsp;koncentracija nije imala uticaj, u ovakvom zemlji&scaron;tu respiracija je bila na veoma niskom&nbsp;nivou pri svim ispitivanim koncentracijama, ali ne kao posledica toksičnosti, već kao&nbsp;posledica činjenice da se degradabilni deo zagađujućih materija degradirao tokom&nbsp;procesa starenja, tako da su u zemlji&scaron;tu zaostali visokomolekularni &nbsp;te&scaron;ko rastvorni&nbsp;ugljovodonici (smole, asfaltne komponente i dr.) sekvestrovani u zemlji&scaron;tu. Merenja biodostupnosti ugljovodonika (ekstrakcijom sa Tween80) pokazala &nbsp;su da je u zemlji&scaron;tu sveže kontaminiranom dizel uljem i sirovom naftom i starim naftnim zagađenjem oko 95%, 85% i 40% ugljovodonika biodostupno, respektivno. Koncentracija rezidualne frakcije mineralnih ulja i ukupnih ugljovodonika dobijena nakon 48 dana laboratorijskog tretmana u skoro svim probama je veća od predviđenih, &scaron;to je posledica bifaznog pona&scaron;anja ugljovodonika u zemlji&scaron;tu, gde se jedan deo uklanja biodegradacijom, dok drugi deo difunduje u pore zemlji&scaron;ta i kompleksira se sa zemlji&scaron;nom organskom materijom. Količina ugljovodonika iz starog naftnog zagađenja zemlji&scaron;ta koja može da pređe u vodenu fazu je mala reda veličine nekoliko mg/l, međutim, u prirodnim uslovima usled spiranja ugljovodonika sa zemlji&scaron;ta ki&scaron;om, postoji verovatnoća da ovi ugljovodonici dospeju u podzemnu vodu iznad maksimalno dozvoljene koncentracije za vodu za piće (MDK = 10 &mu;g/l) i na taj način degradiraju njen kvalitet. Zbog nemogućnosti daljag uklanjanja zagađenja bioremedijacijom, preostala količina zagađujućih materija koja može dospeti u vodenu fazu bi trebalo da se ukloni nekim drugim remedijacionim tehnikama pre njegovog konačnog bezbednog odlaganja u životnu sredinu.</p> / <p>The aims of this study were to examine: (1) the processes that occur during bioremediation of soil contaminated by oil and oil derivatives, which was exposed to spontaneous abiotic and biotic degradation processes over 8 years, using pilot scale biopiles and landfarming techniques to optimise technological parameters with the aim of increasing the efficiency and effectiveness of hydrocarbons biodegradation. (2) the effect of contaminants weathering, concentration, bioavailability and structure on the biodegradation and biotransformation process under controlled laboratory conditions. Over the two years of bioremediation treatment by biopiles and landfarming, the mineral oil content decreased by 52% (from 27.8 g/kg to 13.2 g/kg) and 53% (from 23.2 g/kg to 10.8 g/kg),&nbsp; and the total hydrocarbon content decreased by 43% (from 41.4 g/kg to 23.4 g/kg) and 27% (from 35.3 g/kg to 25.8 g/kg), respectively. The efficiency of mineral oil removal from soil in these two applied bioremediation treatments was practically the same. However, in terms ofthe absolute amount of total hydrocarbons, twice as many total hydrocarbons were removed in the biopile. The mineral oil and total hydrocarbons biodegradation kinetics in the biopile were in good agreement with&nbsp; the kinetic models lnC = lnC0-kt and lnC = lnC0-kt0.5. The mineral oil biodegradation&nbsp;kinetics during the landfarming treatment is relatively well described with those two kinetic models, however, significantly better correlation is obtained by the linear model (C = C0-kt) applied to the first 92 and last 200 days of the experiment. The change in total hydrocarbons content during the landfarming treatment is in relatively good correlation only with the kinetic model lnC = lnC-kt0.5. The laboratory biodegradation investigation showed that hydrocarbon biodegradability and its fate in the environment strongly depend upon the structure, concentration and weathering of the hydrocarbons. Thus, in the case of diesel contaminated soil, as a consequence of&nbsp; its structure, i.e. the presence in a higher concentration of the soluble and toxic midrange n-alkanes, a toxic effect is detected at a diesel oil concentration of 20 mg/g, although this effect is overcome after two weeks, as a consequence of the decreasing&nbsp; concentration of soluble hydrocarbons in biotic and abiotic processes and microbial adaptation. This effect was more pronounced in the case of the soil withthe highest diesel oil concentration. In crude oil contaminated soil, a toxic effect was observed at a much higher hydrocarbon concentration (35 mg/g) than in the diesel oil contaminated soil, which corresponds to the fact that crude oil contains significantly less soluble hydrocarbon. In contrast to these two freshly contaminated soils, the weathered contaminated soil contaminant concentration did not have an effect on hydrocarbon biodegradation, with biodegradation in this soil actually at a low level at all concentrations, not as a consequence of toxicity, but because the degradable part of the contaminant was already degraded during the weathering process, leaving behind only highly condensed hydrophobic organic contaminants (asphaltenes, resins, etc.) sequestered in the soil. The data obtained for hydrocarbons bioavailability (by Tween80 extraction) showed that the bioavailable hydrocarbon fraction from soils freshly contaminated with diesel oil and crude and weathered oil contamination were approximately 95%, 85% and 40%, respectively. The concentration of residual mineral oil fractions and total hydrocarbons obtained after 48 days of laboratory biodegradability treatment in almost all batches was greater than predicted, as a result of the biphasic behaviour of hydrocarbons in the soil, where some were degraded or lost from the soil and some transformed into the recalcitrant fraction. The amount of hydrocarbons from the weathered soil contamination that can be transferred into the water phase is small, of the order of a few mg/l in magnitude, however, under natural conditions, due to hydrocarbons leaching by rainfall, it is possible that these hydrocarbons infiltrate groundwater above&nbsp; the maximum permissible concentration for drinking water (MAC = 10 &mu;g/l) and thus degrade its quality. As it is not possible to achieve further contamination degradation by bioremediation, the remaining amount of pollutants which can be transferred into the water phase should be removed by some other remediation techniques before its final safe disposal in the environment.</p>
4

Procena remedijacionog potencijala sedimenta zagađenog prioritetnim organskim zagađujućim materijama / Investigation of remediation potential of sediment polluted with priority organic pollutants

Grgić Marko 16 August 2019 (has links)
<p>Predmet&nbsp; istraživanja&nbsp; ove&nbsp; doktorske&nbsp; disertacije&nbsp; je&nbsp; procena&nbsp; potencijalno&nbsp; biodostupne&nbsp; frakcije odabranih&nbsp; prioritetnih&nbsp; organskih&nbsp; polutanata&nbsp;&nbsp; (pentahlorbenzena,&nbsp; heksahlorbenzena,&nbsp; lindana, trifluralina, 4-oktilfenola i 4-nonilfenola) u sedimentu, ispitivanje biodegradacionog potencijala ovih&nbsp; jedinjenja&nbsp; u&nbsp; sedimentu&nbsp; u&nbsp; različitim&nbsp; uslovima,&nbsp; kao&nbsp; i&nbsp; procena&nbsp; potencijala&nbsp; stabilizacije<br />sedimenta&nbsp; dodatkom&nbsp; ugljeničnih&nbsp; sorpcionih&nbsp; agenasa.&nbsp; U&nbsp; cilju&nbsp; razvoja&nbsp; metoda&nbsp; za&nbsp; određivanje biodostupnosti odabranih organskih polutanata ispitivane su i&nbsp; optimizovane metode vi&scaron;estepene i jednostepene parcijalne ekstrakcije primenom sledećih hemijskih agenasa:&nbsp; Tenaks&nbsp; smole, XAD-4&nbsp; smole&nbsp; i&nbsp; rastvora&nbsp; ciklodekstrina&nbsp; (2-hidroksipropil-&beta;-ciklodekstrina,&nbsp; &beta;-ciklodekstrina&nbsp; i&nbsp; metil-&beta;-ciklodekstrina).&nbsp; Optimalni&nbsp; agens&nbsp; za&nbsp; procenu&nbsp; biodostupne&nbsp; frakcije&nbsp; odabranih&nbsp; organskih zagađujućih&nbsp; materija&nbsp; sa&nbsp; sedimenta&nbsp; XAD-4&nbsp; smola,&nbsp; a&nbsp; optimalno&nbsp; vreme&nbsp; ekstrakcije&nbsp; primenom jednostepenih&nbsp; ekstrakcija&nbsp; je&nbsp; oko&nbsp; 8&nbsp; h.&nbsp; Procena&nbsp; biodegradacionog&nbsp; potencijala&nbsp; odabranih prioritetnih&nbsp; organskih&nbsp; zagađujućih&nbsp; materija&nbsp; u&nbsp; sedimentu&nbsp; ispitana&nbsp; je&nbsp; u&nbsp; različitim&nbsp; aerobnim&nbsp; i anaerobnim uslovima uz optimizaciju uslova putem biostimulacije i bioaugmentacije. Pokazano je&nbsp; da&nbsp; svih&nbsp; &scaron;est&nbsp; odabranih&nbsp; jedinjenja&nbsp; poseduju&nbsp; značajan&nbsp; potencijal&nbsp; biodegradacije&nbsp; u&nbsp; anaerobnoj sredini&nbsp; pri&nbsp; čemu&nbsp; u&nbsp; slučaju&nbsp; lindana&nbsp; i&nbsp; trifluralina&nbsp; dolazi&nbsp; do&nbsp; potpunog&nbsp; uklanjanja&nbsp; biodostupne količine&nbsp; jedinjenja&nbsp; primenom&nbsp; sva&nbsp; četiri&nbsp; ispitana&nbsp; inokuluma.&nbsp; Aerobni&nbsp; potencijal&nbsp; u&nbsp; ispitanim uslovima&nbsp; pokazali&nbsp; su&nbsp; samo&nbsp; alkil&nbsp; fenoli,&nbsp; gde&nbsp; je&nbsp; takođe&nbsp; uklonjena&nbsp; skoro&nbsp; celokupna&nbsp; količinabiodostupne&nbsp; frakcije&nbsp; jedinjenja&nbsp; u&nbsp; sedimentu&nbsp; (78-85%).&nbsp; Potencijal&nbsp; remedijacije&nbsp; sedimenta dodatkom&nbsp; ugljeničnih&nbsp; materijala&nbsp; ispitan&nbsp; je&nbsp; sa&nbsp; aspekta&nbsp; odabira&nbsp; ugljeničnih&nbsp; sorpcionih&nbsp; agenasa (aktivni&nbsp; ugalj,&nbsp; biougalj&nbsp; i&nbsp; humus);&nbsp; određivanja&nbsp; optimalne&nbsp; količine&nbsp; materijala;&nbsp; isptivanja dugoročnih i kratkoročnih efekata dodatka ovih agenasa na biodostupnost organskih zagađujućih materija&nbsp; kako&nbsp; bi&nbsp; se&nbsp; ispitao&nbsp; efekat&nbsp; starenja &nbsp; i&nbsp; toksičnosti&nbsp; dobijenih&nbsp; sme&scaron;a.&nbsp; Rezultati&nbsp; stabilizacije zagađujućih&nbsp; supstanci&nbsp; u&nbsp; sedimentu&nbsp; pokazuju&nbsp; da:&nbsp; (1)&nbsp; povećanje&nbsp; doze&nbsp; sva&nbsp; tri&nbsp; sorpciona&nbsp; agensa dovodi&nbsp; do&nbsp; povećanja&nbsp; efikasnosti&nbsp; imobilizacije&nbsp; i&nbsp; smanjenja&nbsp; biodostupne&nbsp; frakcije&nbsp; odabranih organskih jedinjenja; (2) starenjem sme&scaron;a sedimenta i&nbsp; sorbenata u toku prvih 90 dana dolazi do daljeg smanjenja biodostupne frakcije svih jedinjenja, nakon čega se biodostupna koncentracija ispitivanih&nbsp; jedinjenja&nbsp; primenom&nbsp; aktivnog&nbsp; uglja&nbsp; ne&nbsp; menja,&nbsp; dok&nbsp; primenom&nbsp; biouglja&nbsp; i&nbsp; humusa&nbsp; dolazi&nbsp; do&nbsp; porasta&nbsp; biodostupne&nbsp; frakcije&nbsp; jedinjenja.&nbsp; Testovi&nbsp; fitotoksičnosti&nbsp; su&nbsp; pokazali&nbsp; da&nbsp; je&nbsp; <em>Zea mays&nbsp; </em>akumulirao&nbsp; značajno&nbsp; veće&nbsp; količine&nbsp; ispitivanih&nbsp; jedinjenja&nbsp; iz&nbsp; netretiranog&nbsp; sedimenta&nbsp; u poređenju sa&nbsp; <em>Cucurbita pepo</em>&nbsp; i&nbsp;<em> Lactuca sativa. </em>Toksičnost sme&scaron;a sedimenta sa aktivnim ugljom i humusom&nbsp; procenjena&nbsp; na&nbsp; osnovu&nbsp; inhibicije&nbsp; luminiscencije&nbsp; na&nbsp; <em>Vibrio&nbsp; fischeri</em>&nbsp; kao&nbsp; i&nbsp; ispitivanjem <em>Zea&nbsp; mays&nbsp; </em>germinacije&nbsp; i&nbsp; produkcije&nbsp; biomase&nbsp; je&nbsp; pokazala&nbsp; značajno&nbsp; smanjenje&nbsp; u&nbsp; odnosu&nbsp; na netretirani&nbsp; sediment.&nbsp; Akumulacija&nbsp; ispitivanih&nbsp; jedinjenja&nbsp; u&nbsp; biomasi&nbsp; <em>Zea&nbsp; mays&nbsp; </em>u&nbsp; netretiranom sedimentu je bila značajno veća u odnosu na sve sme&scaron;e sedimenta i aktivnog uglja i humusa. Sva tri&nbsp; sorbenta&nbsp; pokazala&nbsp; su&nbsp; veliki&nbsp; remedijacioni&nbsp; potencijal&nbsp; za&nbsp; sediment&nbsp; zagađen&nbsp; organskim zagađujućim supstancama, ali je aktivni ugalj pokazao najbolje performance.</p> / <p>The&nbsp; aim&nbsp; of&nbsp; the&nbsp; research&nbsp; in&nbsp; this&nbsp; PhD&nbsp; dissertation&nbsp; is&nbsp; the&nbsp; assessment&nbsp; of&nbsp; the&nbsp; potentially biodegradable&nbsp; fraction&nbsp; of&nbsp; selected&nbsp; organic&nbsp; pollutants&nbsp;&nbsp; (pentachlorbenzene,&nbsp; hexachlorobenzene, lindane,&nbsp; trifluraline,&nbsp; 4-octylphenol&nbsp; and&nbsp;&nbsp;&nbsp; 4-nonylphenol)&nbsp; in&nbsp; the&nbsp; sediment,&nbsp; estimation&nbsp; of&nbsp; the biodegradation potential of these compounds in sediment in different conditions, as well as the assessment&nbsp; of&nbsp; the&nbsp; stabilization&nbsp; potential&nbsp; sediment&nbsp; by&nbsp; the&nbsp; sediment&nbsp; amendment&nbsp; with&nbsp; of&nbsp; carbon rich sorption agents. In order to develop and optimise&nbsp; methods for the bioavailability assessment of&nbsp; the&nbsp; selected&nbsp; organic&nbsp; pollutants,&nbsp; methods&nbsp; of&nbsp; multistage&nbsp; and&nbsp; single-step&nbsp; non&nbsp; exhaustive extraction&nbsp; were&nbsp; studied&nbsp; using&nbsp; the&nbsp; following&nbsp; chemical&nbsp; agents:&nbsp; Tenax&nbsp; resin,&nbsp; XAD -4&nbsp; resin&nbsp; and&nbsp; a cyclodextrin&nbsp; solution&nbsp; (2-hydroxypropyl- &beta;-cyclodextrin,&nbsp; &beta;-cyclodextrin&nbsp; and&nbsp; methyl-&beta;-cyclodextrin).&nbsp; Results&nbsp; showed&nbsp; that&nbsp; optimal&nbsp; agent&nbsp; for&nbsp; estimating&nbsp; the&nbsp; bioavailable&nbsp; fraction&nbsp; of selected organic pollutants from the sediment is XAD-4 resins, and that the optimum extraction time using single-step extraction is about 8 h. The assessment of the biodegradation potential of selected&nbsp; priority&nbsp; organic&nbsp; pollutants&nbsp; in&nbsp; the&nbsp; sediment&nbsp; was&nbsp; examined&nbsp; in&nbsp;&nbsp; various&nbsp; aerobic&nbsp; and anaerobic&nbsp; conditions,&nbsp; with&nbsp; the&nbsp; optimization&nbsp; of&nbsp; conditions&nbsp; through&nbsp; biostimulation&nbsp; and bioaugmentation.&nbsp; It&nbsp; has&nbsp; been&nbsp; shown&nbsp; that&nbsp; all&nbsp; six&nbsp; selected&nbsp; compounds&nbsp; possess&nbsp; significant biodegradation&nbsp; potential&nbsp; in&nbsp; the&nbsp; anaerobic&nbsp; environment,&nbsp; where&nbsp; in&nbsp; the&nbsp; case&nbsp; of&nbsp; lindane&nbsp; and trifluraline there is complete removal of the bioavailable amount of the compound&nbsp;&nbsp; using all four inoculum tested. Aerobic potential under the applied conditions has been showen only for alkyl phenols,&nbsp; where&nbsp; almost&nbsp; all&nbsp; of&nbsp; the&nbsp; bioavailable&nbsp; fraction&nbsp; of&nbsp; the&nbsp; compound&nbsp; in&nbsp; the&nbsp; sediment&nbsp; was removed (78-85%). The potential of sediment remediation with the amendment of sediment withcarbon&nbsp; rich&nbsp; materials&nbsp; was&nbsp;&nbsp; examined&nbsp; from&nbsp; the&nbsp; aspect&nbsp; of&nbsp; selecting&nbsp; carbon&nbsp; sorption&nbsp; agents (activated carbon, biochar and humus); estimation the optimal material doses; the long -term and short-term effects of the addition&nbsp; of these agents on the bioavailability of organic pollutants&nbsp; in order to examine the effect of aging and the toxicity of the resulting mixtures. The results of the stabilization of pollutants in the sediment show that: (1)&nbsp; increasing the dose of all three&nbsp;&nbsp; sorption agents&nbsp; leads&nbsp; to&nbsp; an&nbsp; increase&nbsp; in&nbsp; the&nbsp; immobilization&nbsp; efficiency&nbsp; and&nbsp; reduction&nbsp; of&nbsp; the&nbsp; bioavailable fraction of the selected&nbsp; organic compounds; (2) aging of the amended sediment during the first 90 days results in a further reduction of the biodegradable fraction of all compounds, after which the&nbsp; biodegradable&nbsp; concentration&nbsp; of&nbsp; the&nbsp; selected&nbsp; compounds&nbsp; remain&nbsp; the&nbsp; same&nbsp; in&nbsp; the&nbsp; case&nbsp; of activated carbon amendment, while the bioavailable fraction of&nbsp; the compound increases with the use&nbsp; of&nbsp; biohar&nbsp; and&nbsp; humus.&nbsp; Phytotoxicity&nbsp; tests&nbsp; showed&nbsp; that&nbsp; <em>Zea&nbsp; mays&nbsp;</em> accumulated&nbsp; significantly higher amount of selected organic pollutants from unamended sediment, comparing to&nbsp; <em>Cucurbita pepo&nbsp;</em> and <em>Lactuca sativa</em>. Toxicity of activated carbon and humus amended sediment assessed by <em>Vibrio&nbsp; fischeri&nbsp;</em> luminescence&nbsp; inhibition&nbsp; test&nbsp; and&nbsp; by&nbsp; measuring&nbsp; <em>Zea&nbsp; mays&nbsp; </em>germination&nbsp; and biomass yield was significantly reduced in the amended sediment samples. Accumulation of the selected&nbsp; organic&nbsp; pollutants&nbsp; in&nbsp; the&nbsp; <em>Zea&nbsp; mays</em>&nbsp; biomass&nbsp; in&nbsp; the&nbsp; unamended&nbsp; sediment&nbsp; were&nbsp; a significantly&nbsp; higher&nbsp; than&nbsp; in&nbsp; the&nbsp; humus&nbsp; and&nbsp; activated&nbsp; carbon&nbsp; amended&nbsp; sediment.&nbsp; Both&nbsp; sorbents show&nbsp; potential&nbsp; to&nbsp; be&nbsp; used&nbsp; as&nbsp; remediation&nbsp; agents&nbsp; for&nbsp; organically&nbsp; contaminated&nbsp; sediment,&nbsp; but activated carbon exhibited the better performance.</p>

Page generated in 0.0674 seconds