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Comparison of the amount of sorbed copper ions and effectiveness of sorption on zeolite at various temperatures : master thesis
No full textIspitana je sorpcija bakrovih iona na sintetskom zeolitu NaX u ovisnosti o različitim početnim koncentracijama otopina bakrovog(II) klorida pri dvije različite temperature: 28°C i 31°C. Eksperiment je proveden u šaržnim reaktorima pri brzini miješanja od 200 okr min-1, u trajanju od 1,5 h. Uočeno je da ravnotežna količina sorbiranih bakrovih iona iz otopine bakrovog(II) klorida na zeolitu (qe) raste s povećanjem ravnotežne koncentracije bakrovih iona u otopini (ce) pri obje odabrane temperature provedbe eksperimenta. Također je uočeno da je za sve odabrane početne koncentracije količina sorbiranih bakrovih iona na zeolitu viša pri višoj odabranoj temperaturi što je posljedica smanjene efektivne veličine iona uzrokovane smanjenjem hidratacijskog omotača oko iona. Učinkovitost sorpcije bakrovih iona na zeolitu opada s porastom početne koncentracije bakrovih iona u otopini. Nadalje, uočava se i da je učinak sorpcije bakrovih iona na zeolitu NaX nešto viši ako se proces izvodi pri višoj temperaturi za sve početne koncentracije. Procjenom kvalitete slaganja sorpcijskih modela s eksperimentalnim podatcima, usporedbom izračunatih vrijednosti maksimuma kapaciteta sorpcije i eksperimentalno dobivenog te statističkih parametara RMSE i χ2, može se zaključiti da najbolje slaganje s eksperimentalnim podatcima pokazuje Langmuirova izoterma kod sorpcije bakrovih iona iz otopine bakrovog(II) klorida pri svim odabranim temperaturama provedbe procesa sorpcije.The sorption of copper ions on synthetic zeolite NaX was tested depending on different initial concentrations of copper(II) chloride solutions at two different temperatures: 28°C and 31°C. The experiment was conducted in batch reactors at a mixing speed of 200 rpm for 1.5 hours. It was observed that the equilibrium amount of sorbed copper ions from the solution of copper(II) chloride on zeolite (qe) increases with the increase of the equilibrium concentration of copper ions in the solution (ce) at both selected temperatures of the experiment conducted. It was also observed that for all selected initial concentrations, the amount of sorbed copper ions on the zeolite is higher at a higher selected temperature, which is a consequence of the reduced effective size of the ions caused by the reduction of the hydration shell around the ions. The sorption efficiency of copper ions on zeolite decreases with the increase of the initial concentration of copper ions in the solution. Furthermore, the sorption efficiency of copper ions on zeolite NaX is higher if the process is performed at a higher temperature for all initial concentrations. By assessing the quality of the agreement of sorption models with experimental data, comparing the calculated values of the maximum sorption capacity with the experimentally obtained ones and the statistical parameters RMSE and χ2, it can be concluded that the best fitting with the experimental data is shown by the Langmuir isotherm for the sorption of copper ions from copper(II) chloride solution at all selected temperatures of the sorption process
GC-MS based comparative metabolomies of two breast cancer cell lines treated with nootkatone : master thesis
No full textProliferacija, diferencijacija i preživljenje pojedinačne stanice u višestaničnom je organizmu pažljivo regulirano, dok u stanicama raka te regulacije nema, one nekontrolirano rastu i dijele se, šire po čitavom tijelu i ometaju funkciju normalnih tkiva i organa. Rak je vodeći uzrok smrti u svijetu. Najvažnije u patologiji raka jest razlikovati benigne (dobroćudne) od malignih (zloćudnih) tumora. Drugi način klasifikacije je prema tipu stanica od kojih je rak sastavljen, prema čemu su glavne podvrste: karcinomi, sarkomi, limfomi, leukemije i mijelomi. Rak dojke je vodeći uzrok smrti povezanih s rakom među ženama. Većina tumora dojke ima značajan broj receptora za estrogen, progesteron i humani epidermalni faktor rasta 2 (HER2) te su klasificirani kao trostruko-pozitivni, odnosno trostruko-negativni. Liječenje može biti lokalno i sistemsko ili najčešće njihovom kombinacijom. Stanična linija je skup stanica, odnosno trajno uspostavljena stanična kultura koja se uzgaja u odgovarajućem mediju u kojem će neograničeno proliferirati pri kontroliranim uvjetima. U ovom diplomskom radu korištene su dvije stanične linije raka dojke, MDA-MB-231 i MCF-7 te biciklički seskviterpen nootkaton. Njegovo antiproliferativno djelovanje na dvije stanične linije raka ispitano je u prethodnom istraživanju korištenjem MTT-testa kojim je dokazano da nootkaton ima dobar sveukupni antiproliferativni učinak. Metabolomika je proučavanje svih metabolita u stanici, tkivu ili organizmu. To uključuje identifikaciju i kvantifikaciju staničnih metabolita. Ovdje je upotrijebljen postupak koji se temelji na gašenju metabolizma stanica te sakupljanju i ekstrakciji metabolita. Primijenjen je na dvije stanične linije raka dojke, MDA-MB-231 i MCF-7 uz dodatak i bez dodatka nootkatona (kontrola). Uzeta je koncentracija nootkatona od 0,5 mmol/L pri kojoj je prethodnim korištenjem MTT-testa nootkaton uspješno ubio 50 % stanica. Nakon sakupljanja i ekstrakcije, metaboliti su analizirani GC-MS metodom koja im ujedno omogućava identifikaciju. Dobiveni su kromatogrami i tablice s određenim podatcima te su uspoređene koncentracije identificiranih metabolita u dvije stanične linije raka dojke i zaključeno je do kojih je metaboličkih promjena došlo.Proliferation, differentitation and survival of individual cells in a multicellular organism is carefully regulated, while in cancer cells there is no such regulation, they grow and divide uncontrollably, spread throughout the body and interfere with the function of normal tissues and organs. Cancer is the leading cause of death in the world. The most important thing in cancer pathology is to distinguish between benign and malignant tumors. Another way of classification is according to the type of cells from which the cancer is composed, according to which the main subtypes are carcinomas, sarcomas, lymphomas, leukemias and myelomas. Breast cancer is the leading cause of cancer-related deaths among women. Most breast tumors have a significant number of receptors for estrogen, progesterone and human epidermal growth factor 2 (HER2) and are classified as triple-positive or triple-negative. Treatment can be local or systemic or most often a combination of them. Cell line is a set of cells that is permanently established cell culture grown in a suitable medium in which it will proliferate indefinitely under controlled conditions. Two breast cancer cell lines, MDA-MB-231 and MCF-7, and the bicyclic sesquiterpene nootkatone were used in this diploma thesis. Its antiproliferative activity on two cancer cell lines was investigated in previous research using the MTT-assay, which proved that nootkatone has a good overall antiproliferative effect. Metabolomics is the study of all metabolites in a cell, tissue or organism. This includes the identification and quantification of cellular metabolites. Here, a procedure based on quenching of cells, harvesting and extraction of metabolites was used. It was applied on two breast cancer cell lines, MDA-MB-231 and MCF-7 with and without the addition of nootkatone (control). Nootkatone concentration of 0,5 mmol/L was taken, at which nootkatone successfully killed 50 % of the cells by previous use of the MTT-assay. After harvesting and extraction, the metabolites were analyzed by the GC-MS method, which also enables their identification. Chromatograms and tables with specific data were obtained, the concentrations of identified metabolites in two breast cancer cell lines were compared and it is concluded which metabolic changes occured
Adsorption equilibrium of Cu- and Ni- ions from binary solution on humus Potgrond H : diploma thesis
No full textU radu je ispitana adsorpcija bakrovih i niklovih iona na humusu u ovisnosti o različitim početnim koncentracijama otopina bakrovih (4,814 mmol dm -3 , 9,220 mmol dm -3 , 13,542 mmol dm -3 , 22,695 mmol dm -3 , 33,627 mmol dm -3 ) i niklovih iona (4,059 mmol dm -3 , 8,176 mmol dm -3 , 13,471 mmol dm -3 , 21,510 mmol dm -3 , 31,510 mmol dm -3 ) pri stalnoj temperaturi od 27°C, brzini miješanja od 180 okr min -1 u trajanju od 72 h. Količina adsorbiranih bakrovih iona ( qe ) na humusu neznatno raste porastom početne koncentracije bakrovih iona. Količina adsorbiranih niklovih iona ( qe ) na humusu raste s porastom početne koncentracije niklovih iona te postiže najvišu vrijednost pri najvišoj početnoj koncentraciji niklovih iona u binarnoj otopini. Porastom početne koncentracije bakrovih iona u otopini smanjuje se učinkovitost adsorpcije koja za najvišu vrijednost početne koncentracije iona u otopini ima vrijednost ispod 10%. Učinkovitost adsorpcije iona nikla na humusu opada s porastom početne koncentracije iona teškog metala u otopini, ali u manjoj mjeri u odnosu na adsorpciju bakrovih iona. Iz dobivenih rezultata proizlazi da najbolje slaganje s eksperimentalnim podatcima pokazuje Langmuirov model za adsorpciju bakrovih iona na humusu dok kod adsorpcije niklovih iona na humusu najbolje slaganje pokazuje Freundlichov model.In this diploma thesis, the adsorption of copper and nickel ions on humus was studied depending on the different initial concentrations of copper ion (4,814 mmol dm -3 , 9,220 mmol dm -3 , 13,542 mmol dm -3 , 22,695 mmol dm -3 , 33,627 mmol dm -3 ) and nickel ion solutions (4,059 mmol dm -3 , 8,176 mmol dm -3 , 13,471 mmol dm -3 , 21,510 mmol dm -3 , 31,510 mmol dm -3 ) at a constant temperature of 27°C, a stirring speed of 180 rpm for 72 h. The amount of copper ions adsorbed on humus ( qe ) increases slightly with an increase in the initial concentration of copper ions. The amount of nickel ions adsorbed on humus ( qe ) increases with the increase of initial concentration of nickel ions and reaches its maximum value at the highest initial concentration of nickel ions in binary solution. As the initial concentration of copper ions in the solution increases, the adsorption efficiency decreases reaching a value below 10% for the highest initial concentration of ions in the solution. The adsorption efficiency of nickel ions on humus decreases with the increase of initial concentration of heavy metal ions in solution, but to a lesser extent than the adsorption of copper ions. From the results obtained it is evident that the best fitting with the experimental data of copper ions adsorption on humus is reached when Langmuir model was applied, while Freundlich model showed the best fitting for the adsorption of nickel ions on humus
Determination of residual copper content in soil after the phytoremediation process with the rocket and the garden candytuft : diploma thesis
No full textGlobalni napredak stvorio je mnoge probleme u zaštiti i očuvanju okoliša. Kontaminacija tla otrovnim tvarima se povećala i postala globalni problem. Mnogi od zagađivača su kancerogeni i mutageni te predstavljaju ozbiljan problem za ljudsko zdravlje. Zagađenje tla teškim metalima predstavlja jednu od najvećih briga današnjice. Neke vrste teških metala su otrovne i smrtonosne, čak i u malim koncentracijama, dok druge mogu uzrokovati neurološke poremećaje te druga teška oboljenja. Stoga je sanacija tla zagađenih teškim metalima vrlo važna i u današnje vrijeme naglasak se stavlja na fitoremedijaciju kao ekonomičnu i ekološki prihvatljivu metodu. U ovom diplomskom radu određivana je koncentracija zaostalog bakra, kao teškog metala, u humusu u kojemu su rasle dvije biljke; rukola i štitasta ognjica. Obje biljke su služile kao hiperakumulatori bakra. Određen je sadržaj bakra u šest različito pripremljenih humusa (ukupno 12 za obje biljke): čisti humus bez dodataka, humus s dodatkom letećeg pepela na koji je adsorbiran bakar, humus u koji je dodan humus na koji je adsorbiran bakar, humus s dodatkom ljuski jaja na koje je adsorbiran bakar, humus s dodatkom zeolita na koji je adsorbiran bakar te posljednji humus u kojem su biljke bile zalijevane samo s vodenom otopinom bakrovog(II) sulfata. Uočava se povišen sadržaj bakra u svim uzorcima humusa osim u kontrolnim uzorcima. Na temelju izmjerenog sadržaja bakra može se zaključiti kako su biljke ipak, u većoj ili manjoj mjeri, usvojile bakar iz humusa u koji su dodani adsorbensi na koje je prethodno vezan bakar kao teški metal, kao i one koje su zalijevane isključivo vodenom otopinom bakrovog(II) sulfata.Global progress has created many problems in protecting and preserving the environment. Soil contamination with toxic substances has increased and become a global problem. Many of the pollutants are carcinogenic and mutagenic and represent a serious problem to human health. Soil pollution with heavy metals is one of the biggest concerns of today. Some types of heavy metals are toxic and deadly, even in small concentrations, while others can cause neurological disorders and other serious illnesses. Therefore, remediation of soils contaminated with heavy metals is very important and nowadays the emphasis is placed on phytoremediation as an economical and environmentally friendly method. In this diploma thesis, the concentration of residual copper, as a heavy metal, in humus in which two plants grew was determined; rocket and garden candytuft. Both plants served as copper hyperaccumulators. Copper content was determined in six differently prepared humus (a total of 12 for both plants): pure humus without additives, humus with the addition of fly ash on which copper was adsorbed, humus with the addition of humus on which copper was adsorbed, humus with the addition of egg shells on which copper was adsorbed, humus with the addition of zeolite on which copper was adsorbed, and the last, humus in which the plants were watered only with an aqueous solution of copper(II) sulphate. Elevated copper content is observed in all humus samples except in control samples. Based on the measured copper content, it can be concluded that the plants still, to a greater or lesser extent, adopted copper from humus to which adsorbents were added to which copper was previously adsorbed as a heavy metal, as well as those watered exclusively with aqueous copper(II ) sulphate
Adsorption equilibrium of Cu and Co-ions from solutions of humus Potgrond H : diploma thesis
No full textU radu je ispitana adsorpcija bakrovih i kobaltovih iona na humusu u ovisnosti o različitim početnim koncentracijama otopina bakrovih i kobaltovih iona pri stalnoj temperaturi od 27°C, brzini miješanja od 180 okr min -1 i trajanju eksperimenta od 96 h. Rezultati, nakon provedenih ispitivanja, su pokazali da se količina adsorbiranih bakrovih iona na humusu neznatno mijenja s porastom početne koncentracije bakrovih iona u otopini. Pri početnoj koncentraciji od 12,356 mmol dm -3 postignuta je i maksimalna vrijednost količine adsorbiranih bakrovih iona koja iznosi qe = 0,517 mmol g -1 , dok je najviša učinkovitost adsorpcije bakrovih iona 43,612%. Kod adsorpcije kobaltovih iona za početne koncentracije više od ≈ 8 mmol dm -3 , maksimalna vrijednost količine adsorbiranih iona, qe iznosi 0,041 mmol g -1 . Učinkovitost adsorpcije kobaltovih iona je najviša pri početnoj koncentraciji i iznosi 9,091%. Uzimajući u obzir izračunate vrijednosti za koeficijent korelacije R 2 može se zaključiti kako Langmuirov adsorpcijski model pokazuje najbolje slaganje s eksperimentalnim podatcima za adsorpciju bakrovih i kobaltovih iona na humusu.This thesis presents the results of the copper and cobalt ions adsorption on humus depending on different initial concentrations of copper and cobalt ions solutions at a constant temperature of 27°C, a stirring speed of 180 rpm for 96 h. The results of measurements have shown that the amount of copper ions adsorbed on humus is slightly changing with an increase in the initial concentration of copper ions in solution. At the initial concentration of 12.356 mmol dm -3 , the maximum value of the amount of adsorbed copper ions is achieved, with the value of qe = 0.517 mmol g -1 and the value of the highest adsorption efficiency of copper ions is 43.612%. For the adsorption of cobalt ions for initial concentrations greater than ≈ 8 mmol dm -3 , the maximum value of the amount of adsorbed ions, qe is 0.041 mmol g -1 . The adsorption efficiency of cobalt ions is highest at the initial concentration, with the value of 9,091%. Taking the calculated values for the correlation coefficient R 2 into account, Langmuir adsorption model is the most suitable model for describing adsorption of copper and cobalt ions on humus
APPLICATION OF DEEP EUTECTIC SOLVENTS IN THE EXTRACTION OF PLANT BIOACTIVE COMPONENTS WITH THE ASSESSMENT OF ANTIRADICAL AND ANTIBACTERIAL ACTIVITY : doctoral thesis
No full textSAŽETAK U okviru doktorskog rada ekstrahirane su bioaktivne komponente (fenolne kiseline, flavonoidi, diterpeni, kanabinoidi i kumarini) iz različitog biljnog materijala primjenom hidrofilnih i hidrofobnih niskotemperaturnih eutektičkih otapala. Pripremljenim otapalima ispitana je viskoznost, polarnost i pH. Probir otapala proveden je ekstrakcijom miješanjem i zagrijavanjem, a optimiranje uvjeta ekstrakcije provedeno je za svaku komponentu za ekstrakciju miješanjem i zagrijavanjem, ekstrakciju potpomognutu ultrazvukom i mehanoekstrakciju. Za optimizaciju je odabrano najpogodnije otapalo, a praćen je utjecaj temperature, vremena, udjela vode i brzine kretanja kuglica. Dobiveni rezultati su uspoređeni sa rezultatima dobivenima konvencionalnim otapalima. Za dobivene ekstrakte pri optimalnim uvjetima ispitana je mogućnost izolacije bioaktivnih komponenti primjenom makroporoznih smola, kao i antiradikalna i antibakterijska aktivnost. Pripremljena niskotemperaturna eutektička otapala i makroporozne smole su reciklirane i korištene ponovno za ekstrakciju i izolaciju. Ekstraktima s najvećim udjelom bioaktivnih komponenti pripremljenima s niskotemperaturnim eutektičkim otapalima i konvencionalnim otapalima određena je stabilnost pri četiri različite temperature skladištenja kroz tri mjeseca. Primjenom hidrofilnih i hidrofobnih niskotemperaturnih eutektičkih otapala učinkovito su ekstrahirane komponente iz grupe spojeva kao što su diterpeni, flavonoidi, fenolne kiseline, tenini, kanabinoidi i kumarini. Korištenim otapalima određena je viskoznost, polarnost i pH pri čemu je pokazana najveća korelacija između viskoznosti i udjela komponenti u ekstraktima. Sve korištene tehnike ekstrakcije su se pokazale kao učinkovite, s vrlo malim razlikama u udjelima komponenti u ekstraktu. Ispitani uvjeti ekstrakcije su pokazali različit utjecaj ovisno o komponenti, što govori u prilog selektivnosti ovog načina ekstrakcije. Praćenjem stabilnosti ekstrakata sa najvećim udjelom bioaktivnih komponenti kroz tri mjeseca uočava se pozitivno djelovanje niskotemperaturnih eutektičkih otapala na većinu bioaktivnih komponenti, posebice pri sobnoj temperaturi. Izolacija bioaktivnih komponenti iz ekstrakata dobivenima niskotemperaturnim eutektičkim otapalima pomoću različitih makroporoznih smola se pokazuje kao učinkovit proces sa visokom adsorpcijskim i desorpcijskim prinosima. Fizikalno-kemijska svojstva makroporoznih smola, kao i adsorpcijsko i desorpcijsko vrijeme te volumen desorbensa kao ispitani parametri pokazuju različit utjecaj ovisno o bioaktivnoj komponenti što ponovno pokazuje da se ovaj proces može koristiti selektivno. Osim za izolaciju bioaktivnih komponenti, makroporozne smole su korištene i za recikliranje niskotemperaturnih eutektičkih otapala, a samim procesom desorpcije reciklirane su i makroporozne smole. Korištenjem istog otapala i makroporozne smole u tri ciklusa pokazano je da je učinkovitost otapala u ekstrakciji i makroporozne smole u adsorpciji i desorpciji za većinu bioaktivnih komponenti iznad 60 %. Osim u slučaju ekstrakta vrkute, ekstrakti dobiveni niskotemperaturnim eutektičkim otapalima pokazuju bolju antibakterijsku aktivnost u odnosu na ekstrakte dobivene konvencionalnim otapalima, pri čemu uzorci tretirani makroporoznim smolama pokazuju još bolju aktivnost u odnosu na početni ekstrakt. S druge strane, ekstrakt kadulje i koprive te uzorci nakon tretiranja makroporoznim smolama pokazuju bolju antiradikalnu aktivnost u odnosu na ekstrakte dobivene konvencionalnim otapalima, dok je antiradikalna aktivnost bolja za ekstrakte dobivene konvencionalnim otapalima za industrijsku konoplju i lavandu. Korištenjem niskotemperaturnih eutektičkih otapala u ekstrakciji umjesto organskih otapala smanjuje se negativan utjecaj na okoliš, povećava selektivnost, a kombinacija s inovativnim tehnikama ekstrakcije dovodi do smanjenja utroška energije i vremena.SUMMARY In this doctoral thesis, bioactive components (phenolic acids, flavonoids, diterpenes, cannabinoids and coumarins) were extracted from different plant material using hydrophilic and hydrophobic deep eutectic solvents. For prepared solvents for viscosity, polarity and pH were determined. Solvent screening was performed by stirring and heating extraction, and optimization of the extraction conditions was carried out for each component for stirring and heating extraction, ultrasound-assisted extraction and mechanochemical extraction. The most suitable solvent was chosen for optimization, and the influence of temperature, time, water content, and beads speed was monitored. The obtained results were compared to results obtained with conventional solvents. For the extracts obtained under optimal conditions, the possibility of isolating bioactive components using macroporous resin, as well as antiradical and antibacterial activity, was tested. The prepared deep eutectic solvents and macroporous resins were recycled and used again for extraction and isolation. The stability of extracts with the highest amount of bioactive components prepared with deep eutectic solvents and conventional solvents was determined at four different storage temperatures for three months. Using hydrophilic and hydrophobic deep eutectic solvents effectively extracts components from the group of compounds such as diterpenes, flavonoids, phenolic acids, tannins, cannabinoids and coumarins. Viscosity, polarity and pH were determined with the solvents used, and the highest correlation between viscosity and the amount of components in the extracts was shown. All the extraction techniques used proved to be effective, with very little differences in the amount of the components in the extract. The tested extraction conditions showed a different influence depending on the component, which points to the selectivity of this method of extraction. By monitoring the stability of the extracts with the highest amount of bioactive components for three months, a positive effect of deep eutectic solvents on the majority of bioactive components is observed, especially at room temperature. Isolation of bioactive components from extracts obtained with deep eutectic solvents using different macroporous resins is shown to be an efficient process with high adsorption and desorption yields. The physicochemical properties of macroporous resins, as well as the adsorption and desorption time and the volume of the desorbent as tested parameters show a different influence depending on the bioactive component, which again shows that this process can be used selectively. In addition to the isolation of bioactive components, macroporous resins were also used for recycling deep eutectic solvents, and macroporous resins were also recycled through the desorption process itself. Using the same solvent and macroporous resin in three cycles showed that the efficiency of the solvent in extraction and macroporous resin in adsorption and desorption for most bioactive components is above 60 %. Except in the case of lady mantle extract, extracts obtained with deep eutectic solvents show better antibacterial activity compared to extracts obtained with conventional solvents, while samples treated with macroporous resins show even better activity compared to the initial extract. On the other hand, sage and nettle extract and samples after treatment with macroporous resins show better antiradical activity compared to extracts obtained with conventional solvents, while antiradical activity is better for extracts obtained with conventional solvents for industrial hemp and lavender. Using deep eutectic solvents in extraction instead of organic solvents reduces the negative impact on the environment, increases selectivity, and the combination with innovative extraction techniques leads to a reduction in energy and time consumption
Aromas of decaying Lambic beer : diploma thesis
No full textPivo je jedno od najstarijih i najpopularnijih pića na svijetu. Proces proizvodnje je složen, ali se tijekom povijesti nije značajno mijenjao. S obzirom na proizvodnju, piva se mogu podijeliti na ona koja se proizvode u velikim količinama, a nazivaju se komercijalna ili lager piva, te na craft piva koja se proizvode po tradicionalnim recepturama i u manjim količinama. Procesom spontane fermentacije nastaje i jedinstveno belgijsko lambic pivo karakteristične voćne arome. Bez obzira na način proizvodnje, pivo predstavlja složenu mješavinu sastojaka koja nastaje kuhanjem vode, hmelja i slada, te fermentacijom pripravljene sladovine posredstvom kvasaca. Sadrži visok raspon kemijskih spojeva koji nastaju u svim fazama proizvodnje, a brojni spojevi piva imaju važnu ulogu u formiranju njegova okusa. U ovom su radu identificirani i analizirani spojevi arome iz triju uzoraka lambic piva korištenjem dviju metoda izolacije: mikroekstrakcija vršnih para na krutoj fazi i ekstrakcija tekuće-tekuće. Dobiveni rezultati pokazali su veliku raznolikost identificiranih aromatskih spojeva. Vidljive su određene sličnosti u izoliranim spojevima između uzoraka – najzastupljenije skupine izoliranih spojeva pripadaju alkoholima, kiselinama, aldehidima, ketonima, esterima i fenolima, a 2-feniletanol pojavljuje se u svim ispitivanim uzorcima.Beer is one of the oldest and most popular beverages in the world. The production process is complex, but has not significantly changed throughout history. In terms of production, beers can be divided into those produced in large quantities, known as commercial or lager beers, and craft beers produced according to traditional recipes and in smaller quantities. The process of spontaneous fermentation creates a unique Belgian lambic beer with a characteristic fruity aroma. Regardless of the production method, beer represents a complex mixture of ingredients that is created by boiling water, hops and malt, and by fermenting the prepared wort with the help of yeasts. It contains a wide range of chemical compounds that are formed in all stages of production, and numerous beer compounds play an important role in the formation of its taste. In this study, aromatic compounds from three samples of lambic beer were identified and analyzed using two isolation methods: solid- phase microextraction and liquid-liquid extraction. The results showed a great diversity of identified aromatic compounds. Certain similarities in the isolated compounds between samples are evident – the most prevalent groups of isolated compounds belong to alcohols, acids, aldehydes, ketones, esters, and phenols, with 2- phenylethanol appearing in all tested samples
The influence of hydrocracking process parameters on the quality of diesel fuel : diploma thesis
No full textHidrokrekiranje je jedan od najznačajnijih sekundarnih procesa prerade nafte. Predstavlja katalitički proces temeljen na krekiranju i hidrogenaciji, a ključan je za pretvaranje teških naftnih frakcija u lakše, ekonomičnije proizvode. Proces donosi brojne prednosti, uključujući povećanje proizvodnje lakših ugljikovodika, poboljšanje kvalitete goriva te smanjenje emisije štetnih plinova. U Rafineriji nafte Rijeka (RNR) nalazi se postrojenje za hidrokrekiranje koje kontinuirano proizvodi teški i laki benzin, dizel te nekonvertirano ulje (engl. Unconverted Oil, UCO). Dizel, kao ključan proizvod ovog procesa, ima široku primjenu u motorima s unutarnjim sagorijevanjem. U svrhu ovog diplomskog rada, u lipnju 2023. godine u RNR pratio se proces hidrokrekiranja te su tijekom procesa bilježeni najvažniji procesni parametri. Također, tijekom proizvodnog procesa praćeni su i rezultati laboratorijskih analiza dizel goriva: početak destilacije, T 95 , plamište, količina ukupnog sumpora te količina pare za stripiranje UCO-a. Cilj rada je bio ispitati kako procesni parametri hidrokrekiranja utječu na kvalitetu dizelskog goriva.Hydrocracking is one of the most important secondary processes in oil refining. It represents a catalytic process based on cracking and hydrogenation, crucial for converting heavy oil fractions into lighter, more economical products. The process brings numerous benefits, including increased production of lighter hydrocarbons, improved fuel quality and reduced emission of harmful gases. The Rijeka Oil Refinery (RNR) owns a hydrocracking plant that continuously produces heavy and light gasoline, diesel and unconverted oil (UCO). Diesel, a key product of this process, finds wide application in internal combustion engines. For the purpose of this thesis, in June 2023, the hydrocracking process was monitored in RNR, and the most important process parameters were recorded during the process. Also, at the same time, the results of laboratory analyzes of diesel fuel were documented: initial boiling point, T 95 , flash point, amount of total sulfur and amount of steam for UCO stripping. The aim of the work was to investigate how the process parameters of hydrocracking affect the quality of diesel fuel
Fluid flow through the porous layer : bachelor thesis
No full textCilj ovog rada bio je ispitivanje utjecaja strukture poroznih slojeva, kao i površinske brzine strujanja fluida na vrijednosti pada tlaka u sustavu. Pad tlaka direktna je posljedica otpora koji se pojavljuju tijekom strujanja fluida kroz određeni porozni sloj. Zbog značajnog utjecaja strukture sloja na hidrodinamička zbivanja unutar njega izvršena je detaljna karakterizacija triju ispitivanih slojeva. Za kvantitativan opis koristile su se lako mjerljive veličine te su se tako indirektnim putem dobile određene karakteristike sloja. Eksperimentalno je uočeno da se povećanjem visine poroznog sloja pad tlaka u sustavu značajno povećava. Pri nižim vrijednostima površinskih brzina strujanja fluida (v a < 0,019 m s -1 ) pad tlaka raste linearno s povećanjem visine, dok je za veće vrijednosti v a taj porast eksponencijalan. Također je uočeno da povećanje površinske brzine strujanja, pri konstantnoj visini poroznog sloja, uzrokuje porast energetskih gubitaka. Vrijednost pada tlaka kroz porozni sloj u tom slučaju raste eksponencijalno s povećanjem v a . Usporedbom eksperimentalno dobivenih vrijednosti pada tlaka za ispitivane porozne slojeve s vrijednostima određenim teorijskim jednadžbama, uočava se da su odstupanja najmanja pri korištenju Ergunove i/ili Burke-Plummerove jednadžbe, no za pouzdaniji zaključak sugerira se provedba daljnjih istovjetnih ispitivanja u kojima bi se obuhvatili porozni slojevi većeg raspona veličina čestica.The purpose of this work was to examine the influence of the structure of the porous layers, as well as the surface velocity of the fluid flow on the values of the pressure drop in the system. The pressure drop is a direct consequence of the resistance that appears during the fluid flow through a specific porous layer. Due to the significant influence of the structure of the layer on the hydrodynamic conditions within it, a detailed characterization of the three examined layers was carried out. For the quantitative description, easily measurable quantities were used, thus indirectly obtaining certain characteristics of the layer. It was experimentally observed that by increasing the height of the porous layer, the pressure drop in the system increases significantly. At lower values of surface fluid flow velocities (v a < 0,019 m s -1 ), the pressure drop increases linearly with increasing height, while for higher values of v a , this increase is exponential. It was also observed that an increase in surface flow velocity, at a constant height of the porous layer, causes an increase in energy losses. The value of the pressure drop through the porous layer in that case increases exponentially with increasing v a . By comparing the experimentally obtained pressure drop values for the examined porous layers with the values determined by theoretical equations, it is observed that the deviations are the smallest when using the Ergun and/or Burke- Plummer equation, but for a more reliable conclusion, it is suggested to conduct further identical tests in which the porous layers would be included a larger range of particle sizes
Isolation and identification of basil volatile compounds : bachelor thesis
No full textU ovom završnom radu izvršena je izolacija i identifikacija hlapljivih spojeva iz listova, cvjetova i sjemena bosiljka. Izolacija je provedena metodom mikroekstrakcije vršnih para na krutoj fazi (HS-SPME) koristeći sivo vlakno. Ekstrakcije su provedene u vremenskim intervalima od 40, 60 i 80 minuta. Analiza spojeva je izvršena pomoću vezanog sustava plinska kromatografija - spektrometrija masa (GC-MS). Dobiveni rezultati su se razlikovali u ovisnosti o vremenu ekstrakcije i dijelovima biljke. Najzastupljeniji spoj listova i cvjetova bosiljka je linalol, dok je najzastupljeniji spoj u sjemenu trans-α-bergamoten.In this bachelor thesis, the isolation and identification of volatile compounds from basil leaves, flowers and seeds was performed. The isolation was performed with the solid phase microextraction method (HS-SPME) using a gray fiber. The extractions were carried out at time intervals of 40, 60 and 80 minutes. The analysis of compounds was performed using a coupled gas chromatography-mass spectrometry (GC-MS) system. The obtained results differed depending on the extraction time and plant parts. The most abundant compound in the basil leaves and flowers is linalool, while the most abundant compound in the seeds is trans-α- bergamotene