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Preparation of activated sludge samples for chromatographic analysis of pollutants
No full textPraćenje onečišćivala u uzorcima najučinkovitije se postiže kromatografskim metodama. Međutim, da bi uzorak mogao biti analiziran spomenutom metodom potrebno ga je prethodno pripremiti i prevesti u oblik adekvatan za analizu. U ovom slučaju određivala su se onečišćivala u aktivnom mulju koji je nastao tijekom procesa biorazgradnje. Naime, proces biorazgradnje uobičajeno je sastavni dio postupka obrade otpadnih voda pri čemu nastaju velike količine aktivnog mulja. Biorazgradnja je proces tijekom kojeg različiti mikroorganizmi pretvaraju materijale u prirodne tvari koje potječu iz okoliša kao što su voda ili ugljikovi spojevi. Cilj ovog rada bio je razviti adekvatnu metodu pripreme uzoraka aktivnog mulja nastalog procesom biorazgradnje kako bi se odredila ostatna onečišćivala u spomenutom aktivnom mulju kromatografskom analizom. Onečišćivala praćena u ovom radu su ksenobiotici iz skupine antiparazitika (mebendazol, albendazol i febantel) i insekticida (klotianidin, acetamiprid i tiakloprid). Ksenobiotici pripadaju skupini mikroonečišćivala, odnosno spojevima koji se mogu naći u vodenim sustavima kao posljedica antropogenog utjecaja. Optimizirali su se uvjeti za ekstrakciju mućkanjem (vrijeme trajanja ekstrakcije, volumen otapala, broj okretaja i temperatura ekstrakcije) i ultrazvučnu ekstrakciju (način pripreme mulja, vrijeme trajanja ekstrakcije, volumen otapala, snaga ultrazvučne kupelji i temperatura ekstrakcije). Izabrano optimalno otapalo bila je smjesa otapala MeOH: ACN=50:50 (v:v) ukupnog volumena 5 mL.Monitoring of pollutants in samples is most effectively achieved by chromatographic methods. However, in order for the sample to be analyzed by the mentioned method, it should be prepared beforehand and translated into a form adequate for analysis. In this case, pollutants were determined in the activated sludge that was created during the biodegradation process. Namely, the biodegradation process is usually an integral part of the wastewater treatment process, where large amounts of activated sludge are produced. Biodegradation is the process during which various microorganisms convert materials into natural substances that originate from the environment such as water or carbon compounds. The goal of this work was to develop an adequate method of preparing samples of activated sludge produced by the biodegradation process in order to determine the remaining pollutants in the mentioned activated sludge by chromatographic analysis. The pollutants monitored in this work were xenobiotics from the group of antiparasitics (mebendazole, albendazole and febantel) and insecticides (clothianidin, acetamiprid and thiacloprid). Xenobiotics belong to micropollutants, compounds that can be found in water systems as a result of anthropogenic influence. The conditions for extraction by shaking (extraction time, solvent volume, number of revolutions and extraction temperature) and ultrasonic extraction (method of sludge preparation, extraction time, solvent volume, power of the ultrasonic bath and extraction temperature) were optimized. The optimal solvent chosen was the solvent mixture MeOH: ACN=50:50 (v:v), total volume 5 mL
Frakcionalno diferencirani vremenski nizovi
No full textOvaj rad bavi se modeliranjem vremenskih nizova, s naglaskom na dugoročnu zavisnost u financijskim podacima. Analiziraju se ograničenja klasičnih ARIMA modela i uvodi koncept frakcionalnog diferenciranja kao rješenje za slučajeve sporo opadajuće autokorelacije. Cilj je prikazati kako ARFIMA modeli, koji primjenjuju frakcionalnu diferencijaciju, mogu preciznije modelirati podatke zadržavajući korisnu korelacijsku strukturu. Primijenjena je analiza na vremenskom nizu cijena na zatvaranju S&P 500 indeksa. Uspoređeni su ARIMA i ARFIMA modeli prema uobičajenim evaluacijskim kriterijima (RMSE, MAE, AIC, BIC) i testovima (ADF test, analiza reziduala, Ljung–Box test), uz naglasak na metodu frakcionalnog diferenciranja Marcosa Lópeza de Prada. Rezultati pokazuju da frakcionalni modeli zadržavaju dugoročnu strukturu i postižu usporedivu preciznost, što ih čini vrijednim alatom u kvantitativnoj analizi financijskih podataka.This Master’s thesis addresses the modeling of time series with an emphasis on the phenomenon of long-range dependence in financial data. The limitations of classical ARIMA models are discussed, and the concept of fractional differencing is introduced as a solution in cases where autocorrelation decays slowly — the so-called long-memory phenomenon. The aim of this work is to provide both a theoretical and practical overview of how fractional integration, implemented through ARFIMA models, allows for more accurate modeling of time series while preserving informative correlation structures. The analysis is based on the closing price series of the S&P 500 index. ARIMA and ARFIMA models are compared using standard evaluation metrics (RMSE, MAE, AIC, BIC) and validation tests (ADF test, residual diagnostics, and the Ljung–Box test). Special attention is given to the implementation of fractional differencing methods following the approach of Marcos López de Prado [5]. The results show that models with fractional integration provide forecasts that are comparable to classical models while preserving the structure of long-term autocorrelations. This thesis thus contributes to a deeper understanding of advanced modeling techniques for financial time series and illustrates the potential of fractional analysis in the field of quantitative finance
Increasing the productivity of manufacturing processes in glass manufacturing
No full textU prvom dijelu rada, opisan je nastanak Vitke proizvodnje i pristup implementaciji istih u proizvodne sustave. Potpuno prediktivno održavanje (TPM) i Ukupna učinkovitost opreme (OEE) navode se kao dva ključna alata u poduzećima za praćenje produktivnosti sa ciljem definiranja gubitaka u procesu i eliminaciju istih. Nadalje, dat je osvrt Manufacturing Execution System-a (MES) kao digitalnog rješenja za praćenje proizvodnje. U praktičnom dijelu rada, analizirana je proizvodna linija prerade stakla u poduzeću Press Glass. Iskorišteni su TPM i OEE alati za prepoznavanje i grupiranje gubitaka koji su bili temelj za unapređenje MES sustava čime se omogućilo praćenje proizvodnje i njenih gubitaka u realnom vremenu. Konačno, na temelju prikupljenih podataka, predložena su poboljšanja procesa proizvodnje.In the first part of the paper, the origin of Lean manufacturing and the approach to their implementation in production systems are described. Total Productive Maintenance (TPM) and Overall Equipment Efficiency (OEE) are listed as two key tools in companies to monitor productivity with the aim of defining process losses and eliminating them. Furthermore, a review of the Manufacturing Execution System (MES) as a digital solution for production monitoring is given. In the practical part of the paper, the production line of glass processing in the company Press Glass is analyzed. TPM and OEE tools were used to identify and group losses, which were the basis for the improvement of the MES system, which enabled the monitoring of production and its losses in real time. Finally, based on the collected data, improvements to the production process are proposed
Determination of constitutive and fracture parameters of PBT material reinforced by glass fibres
No full textU današnjem svijetu ispunjenom tehnološki naprednim i modernim vozilima, električni konektori imaju iznimno veliku ulogu pri povezivanju različitih električnih sustava. Među najpoznatijim materijalima za izradu modernih električnih konektora je polibutilen tereftalat (PBT). Jedna od glavnih prednosti mu je relativno jednostavna mogućnost ojačavanja mehaničkih svojstava ovisno o zahtjevima kupca. Varijacija PBT materijala koja će se koristiti u ovom radu je PBT ojačan s 30% staklenih vlakana (PBT-GF30). Tema ovog rada je određivanje i validiranje parametara konstitutivnog i lomnog ponašanja materijala PBT-GF30. Rad je podijeljen u šest poglavlja. U prvom poglavlju dan je kratki uvod i osvrt na temu PBT materijala te javno/internetski dostupnih mehaničkih svojstva vezana za njega. Unutar drugog poglavlja definiran je konstitutivni model ponašanja materijala. Počevši od jednostavnog linearnog elastičnog modela, zatim uzimajući u obzir elasto-plastično ponašanje i na kraju mehaniku oštećenja i loma, razvijen je konstitutivni model ponašanja konstrukcije. Tema ovog rada je ispitivanje krhkog tipa loma, koji se odvija pri malim deformacijama zbog iznimnog nagomilavanja pogrešaka u materijalu u kratkom vremenu. U trećem poglavlju opisano je eksperimentalno ispitivanje testnog uzorka, epruvete, jednoosnim statičkim vlačnim testom. Također, norma prema kojoj su izrađeni testni uzorci i DIC metoda obrade rezultata je obuhvaćena ovim poglavljem. Unutar četvrtog poglavlja materijalni model je validiran numeričkim simulacijama statičkog vlačnog testa korištenjem programskog paketa Abaqus®. Nadalje, peto poglavlje je iskorišteno za primjenu razvijenog materijalnog modela na stvarni problem/konstrukciju. Za primjer je iskorišten TPA osigurač (Terminal position assurance) razvijen unutar tvrtke Yazaki Europe Limited Zagreb (YELZ). Šesto poglavlje je ujedno i zaključno poglavlje. U njemu je dan zaključak i popratni komentari vezani uz kalibraciju ovisno o geometriji problema. Također, dan je prijedlog dodatnog poboljšanja materijalnog modela koji bi uključio lomno ponašanje konstrukcije pri tlačnom i smičnom opterećenju.In today’s world of technologically advanced and modern vehicles, electrical connectors play a critical role in linking various electrical systems. Among the most prominent materials used in the manufacture of modern electrical connectors is polybutylene terephthalate (PBT), valued particularly for its relatively simple adaptability in reinforcing mechanical properties based on customer specifications. The variant of PBT used in this study is reinforced with 30% glass fibers (PBT-GF30). This work focuses on determining and validating the constitutive and fracture behavior parameters of the PBT-GF30 material. The study is organized into six chapters. The first chapter provides a brief introduction to PBT materials and a review of publicly available data regarding their mechanical properties. In the second chapter, the constitutive model of material behavior is defined. Beginning with a basic linear elastic model, it progresses to include elasto-plastic behavior and ultimately damage and fracture mechanics, resulting in a comprehensive constitutive model for structural behavior. This study specifically examines brittle fracture, which occurs at small deformations due to the rapid accumulation of defects within the material over a short period.The third chapter describes the experimental testing of the specimen through a uniaxial static tensile test. Standards for specimen fabrication and the Digital Image Correlation (DIC) method used for data analysis are also discussed here. In the fourth chapter, the material model is validated using numerical simulations of the static tensile test conducted with the Abaqus® software package. The fifth chapter then applies the developed material model to a real-world scenario, with a Terminal Position Assurance (TPA) component developed by Yazaki Europe Limited Zagreb (YELZ) serving as the practical example. The sixth and final chapter presents the conclusion, along with observations related to calibration based on problem geometry. Additionally, a proposal for further improvement of the material model is provided, which would incorporate fracture behavior under compressive and shear loading conditions
Monitoring the migration of additives from multiple recycled polyethylene microplastics
No full textPolimerni materijali nalaze se svuda oko nas i koriste se u raznim proizvodima prehrambene, kozmetičke, građevinske i drugih industrija, pri čemu je polietilen jedan od najčešće korištenih polimera. Dodavanjem aditiva poboljšavaju se određena svojstva polimera koja im omogućuju primjenu u različitim industrijama. S porastom globalne proizvodnje i uporabe polimernih materijala povećava se i količina plastičnog otpada. Mehaničko recikliranje često se smatra efikasnim rješenjem za njegovo smanjenje. Iako u literaturi postoji puno istraživanja koja se temelje na proučavanju polimera i njihovih svojstava, malo se njih koncentrira na to kako višestruko recikliranje utječe na otpuštanje aditiva iz plastike. Cilj ovoga rada bio je proučavanje utjecaja višestrukog recikliranja na migraciju aditiva iz polietilenske mikroplastike. U tu svrhu pripremljena su dva uzorka. Prvi uzorak se sastojao od polietilena (PE) i antioksidansa, dok se drugi uzorak sastojao od PE-a u koji su dodani antioksidansi i plastifikator. Nakon pripreme uzoraka u laboratorijskom ekstruderu provedena je simulacija pet ciklusa mehaničkog recikliranja. Nakon svakog ciklusa uzorci su usitnjeni do veličine mikroplastike. Kako bi se ustanovile promjene u strukturi, toplinskoj stabilnosti i stupnju kristalnosti uzoraka uzrokovane aditivima, provedena je karakterizacija nakon 1., 3. i 5. ciklusa recikliranja. Metode karakterizacije uključivale su infracrvenu spektroskopiju s Fourierovom transformacijom (FTIR), termogravimetrijsku analizu (TGA) i diferencijalnu pretražnu kalorimetriju (DSC). Isto tako, praćena je i migracija aditiva iz mikroplastike u vodeni medij, prilikom čega je određen sadržaj ukupnog organskog ugljika, omjer biorazgradivosti i toksičnost na organizmima Vibrio fischeri i Daphnia magna.Polymeric materials are all around us and are used in various products such as food, cosmetics, construction and other industries, whereby polyethylene is one of the most used polymers. The addition of additives is essential for enhancing certain properties of polymers, allowing their application in various industries. With increasing global production and usage of polymer materials, the amount of plastic waste is also increasing. Mechanical recycling is considered an effective way of solving this problem. Although there are many studies about polymers and their properties, not many of them are focused on the effect of multiple recycling cycles on the migration of additives from plastic. The aim of this thesis was to examine the effect of multiple recycling cycles on migration of additives from polyethylene microplastics. For this purpose, two samples were prepared. One of them was polyethylene (PE) with antioxidants, while the second one was PE with antioxidants and plasticizer. After preparation, a simulation of five recycling cycles was conducted in a laboratory extruder. After each cycle, the samples were ground to microplastic size. To establish changes in structure, thermal stability and degree of crystallinity of the samples, the characterization was done after 1st, 3rd and 5th cycle of recycling. These methods of characterization included Fourier-Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The migration of additives from microplastic to water was also monitored, and total organic carbon (TOC), ratio of biodegradability and toxicity on organisms Vibrio fischeri and Daphnia magna were determined
Analysis of one-year beach profile changes in Omiš and Duće area
No full textPlaže u području grada Omiša i naselja Duće jedne su od rijetkih pješčanih plaža na istočnoj obali Jadranskog mora, a porijeklo sedimenta plaža je u najvećoj mjeri pijesak taložen na ušću rijeke Cetine. Tijekom 20. stoljeća, urbanizacija grada Omiša i Duća, te izgradnja hidroelektrana na rijeci Cetini značajno su smanjile budžet sedimenta dostupnog za prirodnu nadohranu plaža. S obzirom na rijetkost pojave plaža na istočnoj obali Jadranskog mora i važnost njihovog očuvanja, cilj ovog diplomskog rada je analiza jednogodišnjih promjena profila pješčanih plaža na tom području. Tijekom 2023. godine provedena su mjerenja profila plaža na pet odabranih lokacija kako bi se utvrdile morfološke promjene. Te promjene povezane su s osnovnim fizičkim karakteristikama sedimenta te s prikupljenim vjetrovnim i izračunatim valnim prilikama u periodu praćenja. Analizom svih prikupljenih podataka pokušao se procijeniti maksimalni odobalni doseg kretanja sedimenta (depth of closure), a time i stabilnost plaža, te prikladnost jednogodišnjeg vremenskog okvira praćenja varijacija profila na potrebe upravljanja plažama.The beaches in the area of the city of Omiš and the settlement of Duće are some of the rare sandy beaches on the eastern coast of the Adriatic Sea, and the origin of the beach sediment is mostly sand deposited at the mouth of the Cetina River. During the 20th century, the urbanization of the city of Omiš and Duće, and the construction of hydroelectric power plants on the Cetina River significantly reduced the sediment budget available for natural beach replenishment. Given the rarity of beaches on the eastern coast of the Adriatic Sea and the importance of their preservation, the aim of this thesis is to analyze one-year changes in the profile of sandy beaches in that area. During 2023, beach profile measurements were carried out at five selected locations to determine morphological changes. These changes are related to the basic physical characteristics of the sediment and to the collected wind and calculated wave conditions during the monitoring period. By analyzing all collected data, an attempt was made to estimate the maximum offshore reach of sediment movement (depth of closure), and thus the stability of the beaches, and the suitability of the one-year time frame for monitoring profile variations for the needs of beach management
Feline Adrenal Diseases
No full textUzroci poremećaja nadbubrežne žlijezde mačaka mogu biti primarni, sekundarni i
tercijarni, a očituju se hipo- ili hiperfunkcijom žlijezde. Primarni uzroci odnose se na različita
patološka stanja samog nadbubrega poput tumora ili direktnog oštećenja kore ili srži.
Sekundarni uzroci se javljaju posljedično poremećaju funkcije hipofize, a tercijarni
posljedično poremećaju funkcije hipotalamusa. Simptomi većine ovih bolesti su uglavnom
vrlo nespecifični te mogu upućivati na bolesti nekog drugog organskog sustava ili poremećaja
neke druge endokrine žlijezde pri čemu je dodatno otežavajuća činjenica da mačke kao
pacijenti, nimalo nisu slične psima, što ponekad rezultira propustom od strane vlasnika i/ili
veterinara. Hiperadrenokorticizam (Cushing-ov sindrom) i hiperaldosteronizam (Conn-ov
sindrom) u mačaka su bolesti adrena koje su nažalost često zapostavljene, a ponekad i
potpuno izostavljene s liste diferencijalnih dijagnoza zbog širokog spektra različitih
simptoma koji kliničara mogu zavarati i pogrešno usmjeriti. Upravo zbog navedenog, u
mačaka često izostaje konačna dijagnoza bolesti nadbubrežne žlijezde, no uslijed razvoja i
napretka dijagnostičkih metoda ove bolesti ipak bivaju sve češće potvrđene.The causes of cat adrenal gland disorders can be primary, secondary and tertiary, and are
manifested by hypo- or hyperfunction of the gland. The primary causes relate to various
pathological conditions of the adrenal gland itself, such as tumors or direct damage to the
cortex or marrow. Secondary and tertiary causes occur because of hypothalamus
dysfunction. The symptoms of these diseases are generally non-specific and may point to
diseases of another organ system or disorders of another endocrine gland, where the fact that
cats as patients are not at all like dogs is even more difficult, which sometimes results in an
oversight by the owner and/or veterinarian. Hyperadrenocorticism (Cushing's syndrome) and
hyperaldosteronism (Conn's syndrome) in cats are adrenal diseases that are unfortunately
often neglected, and sometimes completely absent from the list of differentials due to a wide
range of different symptoms that can mislead the clinician. Precisely because of the above
mentioned, a final diagnosis of adrenal gland disease is often missing in cats, still due to the
development and progress of diagnostic methods, these diseases are being confirmed
increasingly often
Influence of matrix composition on photolytic and photcatalytic degradation of N-nitrosamines
No full textU procesu dezinfekcije vode mogu nastati dezinfekcijski nusprodukti (DNP) koji su štetni za ljudsko zdravlje. Primjer dezinfekcijskih nusprodukata su nitrozamini koji sadrže dušik te doprinose toksičnosti vode. Zbog toga je neophodno razviti učinkovite metode uklanjanja DNP-a iz vode, kao što su napredni oksidacijski i membranski procesi. U ovom radu istražena je fotolitička i fotokatalitička razgradnja N-nitrozamina korištenjem UV-LED fotoreaktora. Analizirani N-nitrozamini su: N-nitrozo-dimetilamin (NDMA), N-nitrozodietilamin (NDEA),
N-nitrozomorfolin (NMOR) i N-nitrozopiperidin (NPIP). Za izvor zračenja korištene su
UV-A (λ = 365 nm) i UV-C (λ = 272 nm) svjetleće diode. Fotokatalitička razgradnja nitrozamina izvedena je pomoću tankog filma TiO2 te uz pomoć suspenzije TiO2. Fotolitička razgradnja ispitana je u ultračistoj, sintetskoj bazenskoj, morskoj i boćatoj vodi te u retentatu nakon
RO/NF postupka. Istražen je utjecaj valne duljine zračenja, broja LED dioda te sastava matrice na kinetiku razgradnje N-nitrozamina. Rezultati su pokazali da je najučinkovitiji fotoreaktor s najvećim brojem UV-A LED dioda za sve ispitane matrikse tijekom perioda od 60 min.Disinfection by-products (DBP) are harmful to human health and are formed during water disinfection. Examples of disinfection by-products are nitrosamines that contain nitrogen and contribute to the toxicity of drinking water. Therefore, it is necessary to develop effective methods for removing DBPs from water, such as advanced oxidation and membrane processes. In this paper, the photolytic and photocatalytic degradation of N-nitrosamines was investigated using a UV-LED photoreactor. The analyzed N-nitrosamines are:
N-nitroso-dimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosomorpholine (NMOR), and N-nitrosopiperidine (NPIP). UV-A (λ = 365 nm) and UV-C (λ = 272 nm)
light-emitting diodes were used as the radiation source. The photocatalytic degradation of nitrosamines was carried out using a thin film of TiO2 and with the help of a TiO2 suspension. The photolytic degradation was carried out in ultrapure, synthetic pool, sea, and brackish water and in retentate after the RO/NF process. The influence of the radiation wavelength,
the number of LEDs and the type of matrix on the kinetics of N-nitrosamine degradation were investigated. The results showed that the most efficient photoreactor is that with UV-A LED diodes with six columns of UV-LED strips in all tested matrices during a time period of 60 min
Analysis of the effectiveness of the isolated microorganisms in bioremediation of oil and oil products
No full textNafta predstavlja jedan od glavnih energenata današnjice i njena upotreba vrlo je široka. Svakodnevnim korištenjem i eksploatacijom nafte dolazi do neželjenog ispuštanja nafte u okoliš, što predstavlja veliki ekološki problem. Sve se više istražuju nove, „zelene“ tehnologije koje se mogu koristiti za uklanjanje naftnog onečišćenja bez negativnog utjecaja na okoliš. Bioremedijacija može uz prirodne mikroorganizme razgraditi prisutno onečišćenje. Mikroorganizmi proizvode enzime koji razgrađuju naftu i naftne derivate ili koriste naftu kao izvor energije za svoj rast i razmnožavanje. Identifikacija autohtonih mikroorganizama te poznavanje njihovih svojstava od velike je važnosti kako bi se povećala učinkovitost bioremedijacije. U ovom radu provedena je identifikacija i karakterizacija autohtonih mikrobnih kultura iz uzorka tla onečišćenog naftnim derivatima u šaržnim uvjetima i u periodu 28 dana. Dobivene vrijednosti CFU su se kretale u rangu od 6,26 × 10^4 do
7,60 × 10^8 /g tla. Rezultati pokazuju da je aktivnost bakterija i gljiva bila najveća pri pH-vrijednosti 7,8 i 7,0. Na temelju morfologije, biokemijskih testova i MALDI TOF analize identificirane su slijedeće bakterijske vrste: Lysobacter daejeonensis, Cupriavidus necator, Novosphingobium taihuense i Staphylococcus warneri.Oil is one of the most important sources of energy today and its use is widespread. The daily use and exploitation of oil results in the unwanted release of oil into the environment, which is a major environmental problem. New "green" technologies are being explored that can eliminate oil pollution without harming the environment. Bioremediation can break down existing pollution with natural microorganisms. Microorganisms produce enzymes that can break down oil and oil derivatives or use oil as an energy source for their growth and reproduction. Identification of indigenous microorganisms and information about their properties are of great importance to increase the efficiency of bioremediation. In this study, the identification and analysis of the efficiency of microbial cultures from a soil sample contaminated with oil derivatives were carried out under batch conditions over a period of 28 days. The CFU values obtained ranged from 6.26 × 10^4 to 7.60 × 10^8 /g soil. The results show that bacterial and fungal activity was highest at pH 7.8 and 7.0, respectively. Based on morphology, biochemical tests and MALDI TOF analysis, the following bacterial species were identified: Lysobacter daejeonensis, Cupriavidus necator, Novosphingobium taihuense and Staphylococcus warneri
Potential of environmental bacterial culture for the biodegradation of xenobiotics
No full textSvijet se sve više urbanizira. Rezultat sve veće urbanizacije je rast raznih industrija, poput farmaceutske. Upravo ovakvi spojevi koji se prirodno ne nalaze u okolišu, ali zbog antropogenih aktivnosti dospijevaju u njega, nazivaju se ksenobiotici. Potencijal okolišnih bakterijskih kultura za biorazgradnju ksenobiotika obećavajući je pristup u rješavanju nastalih ekoloških izazova povezanih s postojanošću kemijskih onečišćivača u okolišu. Iskorištavanjem metaboličke aktivnosti bakterijskih kultura iz okoliša, ovaj pristup nudi isplativu i učinkovitu alternativu konvencionalnim postupcima remedijacije i ima potencijal za ublažavanje negativnih učinaka ksenobiotika na zdravlje ljudi i okoliš. U ovom radu procesom biorazgradnje provedeno je uklanjanje farmaceutika amoksicilina pomoću bakterijske kulture Pseudomonas aeruginosa izolirane iz okoliša. Pokus je proveden u šaržnom reaktoru i aerobnim uvjetima u periodu od 12 dana s početnim koncentracijama amoksicilina od
278 mg L^-1 (Pa-1) i 658 mg L^-1 (Pa-2). Prema provedenim testovima osjetljivosti
P. aeruginosa je pokazala otpornost na ispitivani ksenobiotik i nastale produkte.
Rezultati istraživanja pokazuju učinkovitost procesa od 49,6 % za Pa-1, te 36,2 % za Pa-2.The world is becoming increasingly urbanized. The result of increasing urbanization is the growth of various industries, such as the pharmaceutical industry, that produce various compounds. These compounds, which do not occur naturally in the environment but enter the environment due to anthropogenic activities, are known as xenobiotics. The potential of bacterial cultures in the environment to biodegrade xenobiotics is a promising approach to solving environmental problems related to the persistence of chemicals in the environment. By utilizing the metabolic activity of bacterial cultures in the environment, this approach offers a cost-effective and efficient alternative to remediation methods and has the potential to mitigate the harmful effects of xenobiotics on human health and the environment. In this work, the biodegradation process was used to remove amoxicillin using a bacterial culture of Pseudomonas aeruginosa isolated from the environment. The experiment was carried out in a batch reactor and under aerobic conditions for a period of 12 days with initial amoxicillin concentrations of 278 mg L^-1 (Pa-1) and 658 mg L^-1 (Pa-2). According to the sensitivity tests performed, Pseudomonas aeruginosa showed resistance to the xenobiotics tested and the resulting products. The research results showed a process efficiency of 49.6 % for Pa-1 and 36.2 % for Pa-2