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Synthesis of nanomagnetite and preparation of ferrofluids using various surfactants : diploma thesis
No full textProvedena je sinteza nanomagnetita iz željezovih soli FeCl 3 i FeCl 2 . Iz sintetiziranog nanomagnetita pripravljeni su ferofluidi primjenom tetrametilamonijeva hidroksida, oleinske kiseline, motornog ulja i amonijeva oleata kao surfaktanta. Sintetiziranom nanomagnetitu je određen prosječni promjer čestica pomoću TEM-a, dok je priređenim ferofluidima procjenjena magnetska aktivnost. Određeni su optimalni parametri sinteze nanomagnetita kao i prikladnost primjenjenih surfaktanata. Na osnovi dobivenih rezultata i usporedbom s odgovarajućim znanstvenim radovima izneseni su zaključci o uspješnosti predloženih metoda priprave ferofluida.The synthesis of nanomagnetite from iron salts FeCl 3 and FeCl 2 was conducted. Ferrofluids were prepared from the synthesized nanomagnetite using tetramethylammonium hydroxide, oleic acid, motor oil and ammonium oleate as surfactants. The mean particle diameter of the synthesized nanomagnetite was determined using TEM, while the magnetic activity of the prepared ferrofluids was evaluated. The optimal parameters of nanomagnetite synthesis were determined, as well as the suitability of the surfactants applied for the preparation of ferrofluids. On the basis of the obtained results and comparison with corresponding scientific works, conclusions were drawn about the success of the proposed methods of ferrofluid preparation
EFFECT OD ADDITION OF THE HUMISTAR SOLUTION ON ZINC AND LEAD UPTAKE FROM THE AQUEOUS SOLUTION ONTO NATURAL ZEOLITE : bachelor thesis
No full textIspitano je vezanje iona olova i cinka iz vodenih otopina dviju različitih početnih koncentracija na prirodnom zeolitu u prisustvu organske tvari. Za simulaciju organske tvari je poslužila otopina Humistar ® preparata koji sadrži huminske i fulvinske kiseline. Komercijalno se proizvodi i primjenjuje kao dodatak tlu s ciljem boljeg rasta i prinosa biljaka. Izvedeni su eksperimenti vezanja metalnih iona uz različite dodatke 10%-tne otopine Humistara ® pri konstantnim eksperimentalnim uvjetima. Nakon uravnoteženja sa zeolitom i razgradnje organske tvari, u tekućoj fazi određene su koncentracije olova i cinka AAS tehnikom. Dobiveni rezultati pokazuju da je količina vezanog olova kao i stupanj uklanjanja značajno veći u odnosu na cink što je u skladu s dosadašnjim istraživanjima. Međutim dodatak organske tvari utječe na smanjenje količine vezanja i stupnja uklanjanja kod olova i cinka te je to smanjenje jače izraženo s povećanjem dodatka organske tvari. Može se pretpostaviti da dolazi do inhibicije vezanja metalnih iona na zeolit koja je posljedica više mehanizama prijenosa metalnih iona. Prva je pretpostavka da se metalni ioni vezuju, tj. sorbiraju na molekule huminskih i fulvinskih kiselina, čime se onemogućava ionska izmjena i oni zaostaju u filtratu nakon uravnoteženja sa zeolitom. Druga je pretpostavka da se molekule organske faze sorbiraju na površini zeolita, blokirajući aktivna mjesta dostupna za ionsku izmjenu.The binding of lead and zinc ions from aqueous solutions of two different initial concentrations onto natural zeolite in the presence of organic matter has been examined. The Humistar ® solution, which contains humic and fulvic acids, was used to simulate organic matter. It is commercially produced and applied as a soil additive with the aim of better plant growth and yield. Experiments of metal ions removal have been performed with different additions of 10% Humistar ® solution under constant experimental conditions. After equilibration with zeolite and decomposition of the organic matter, lead and zinc ions concentrations have been determined in the liquid phase using the AAS technique. The obtained results show that the amount of bound lead as well as removal efficiency is significantly higher compared to zinc, which is in accordance with previous research. However, the addition of organic matter reduces the amount of binding of lead and zinc as well as removal efficiency, and this reduction is more pronounced with the increase of the addition of organic matter. It can be assumed that there is an inhibition of the binding of metal ions onto zeolite, which is a consequence of several mechanisms of metal ions mass transfer. The first assumption is that metal ions are bound, i.e. sorbed to molecules of humic and fulvic acids, which disables their ion exchange onto zeolite and they remain in the filtrate after equilibration with zeolite. Another assumption is that the molecules of the organic phase are sorbed on the zeolite surface, blocking the active sites available for ion exchange
Influence of storage time on the quality and aroma profile of virgin olive oils : diploma thesis
No full textMaslina (Olea europea L.) je najrasprostranjenija biljka na području jadranskog dijela Hrvatske još od antičkog doba. Kao izuzetno rasprostranjena voćna vrsta, s dugom poviješću uzgoja odlikuje se velikim brojem sorti. Najvrjedniji i glavni proizvod ploda masline je maslinovo ulje, koje je iznimno cijenjeno zbog svojih zdravstvenih svojstava i jedinstvenog okusa. Za razliku od ostalih masti i ulja, koji se koriste u ljudskoj prehrani, maslinovo ulje postiže najveću cijenu na tržištu. Zato se maslinova ulja podvrgavaju ispitivanju kvalitete i autentičnosti u cilju sprječavanja bilo kojih oblika patvorenja. Osim berbe i prerade plodova na kvalitetu maslinovog ulja utječu adekvatna dorada i skladištenje. Stoga je od velikog značaja skladištiti ulje u odgovarajućoj ambalaži i zaštititi ga od negativnog utjecaja vanjskih čimbenika. Cilj ovog diplomskog rada bio je utvrditi kako vrijeme čuvanja utječe na kvalitetu i aromatični profil djevičanskog maslinovog ulja. U ovom istraživanju analize su provedene na tri uzorka djevičanskih maslinovih ulja, nakon prerade te svako tri mjeseca u periodu od godine dana čuvanja u zatvorenoj tamnoj staklenoj boci na suhom i tamnom mjestu pri sobnoj temperaturi. Prema rezultatima pokazatelja kvalitete utvrđeno je kako su se vremenom skladištenja blago povećale vrijednosti pojedinih parametara kvalitete, te ulja i nakon godine dana pripadaju kategoriji ekstra djevičanskih maslinovih ulja. Nadalje, vrijednosti ukupnih fenola u uljima su se tijekom skladištenja smanjile, a najveći sadržaj je utvrđen u ulju sorte Oblica. Aromatični profil ulja tijekom skladištenja također je doživio promjene. Uglavnom su se odnosile na smanjenje udjela C-6 aldehida (E)-heks- 2-enala te rast udjela C-6 alkohola (heksanola) odgovornih za „zelene“ i svježe note. Rezultati senzorske analize ukazuju na blagi pad intenziteta pozitivnih senzorskih obilježja te odsustvo senzorskih mana te se sva ulja i prema ovom pokazatelju kvalitete mogu kategorizirati kao ekstra djevičanska maslinova ulja.Olive (Olea europea L.) is the most widespread plant in the area of the Adriatic part of Croatia since ancient times. As an extremely widespread fruit species, with a long history of cultivation, it is characterized by a large number of varieties. The most valuable and main product of the olive fruit is olive oil, which is highly valued for its health properties and unique taste. Unlike other fats and oils, which are used in human nutrition, olive oil reaches the highest price on the market. That is why olive oils undergo quality and authenticity testing in order to prevent any form of adulteration. Except harvesting and fruit processing, the quality of olive oil is affected by adequate processing and storage. Therefore, it is of great importance to store the oil in appropriate packaging and protect it from the negative influence of external factors. The aim of this thesis was to determine how storage time affects the quality and aromatic profile of virgin olive oil. In this research, analyses were performed on three virgin olive oil samples after processing and every three months for a period of one year, stored in a closed dark glass bottle in a dry and dark place at room temperature. According to the results of the quality indicators, it was determined that the values of certain quality parameters slightly increased during storage, and that the oils still belong to the category of extra virgin olive oils even after a year. Furthermore, the values of total phenols in the oils decreased during storage, and the highest content was determined in the oil of the Oblica variety. The aromatic profile of the oils also underwent changes during storage. They were mainly related to the reduction of the content of C-6 aldehyde (E)-2-hexenal and the increase of the conten of C-6 alcohol (hexanol) which are responsible for "green" and fresh notes. The results of sensory analysis indicate a slight decrease in the intensity of positive sensory attributes and no sensory defects perceived which means that all oils can be categorized as extra virgin olive oils according to this quality indicator
Green synthesis of colloidal silver by chemical reduciton using flower honey : bachelor thesis
No full textU ovom radu proučavana je sinteza nanočestica srebra pomoću cvjetnog meda pri pH vrijednosti 6, 7, 8. 9 i 10. Kao izvor srebra korišten je srebrov nitrat koncentracije 0,001 mol dm -3 , a pH vrijednost je namještana otopinom natrijeva hidroksida. Prvi dokaz nastanka koloidnog srebra bilo je određivanje intenziteta Tyndallova efekta u svakom uzorku uslijed propuštanja laserske zrake kroz koloide. UV-Vis spektrofotometrom u području valnih duljina 300-600 nm i TEM (Transmisijski elektronski mikroskop) analizom izvršena je karakterizacija uzoraka nastalog koloidnog srebra. UV-Vis spektroskopijom dobiveni su oštri apsorpcijski maksimumi pri valnim duljinama 420-450 nm čime je dokazano nastajanje nanočestica srebra. Pomoću PWHM metode procjenjena je veličina nanočestica srebra za sve uzorke i iznosila je od 10-65 nm. TEM analizom potvrđeno je dobivanje sferičnih nanočestica srebra s prosječnom veličinom čestica od 17-39 nm.In this work, the synthesis of silver nanoparticles with flower honey at pH values of 6, 7, 8, 9 and 10 was studied. Silver nitrate with a concentration of 0.001 mol dm -3 was used as the silver source, and the pH was adjusted with sodium hydroxide solution. The first evidence of colloidal silver formation was the determination of the intensity of the Tyndall effect in each sample as a result of the passage of a laser beam through the colloids. Using a UV-Vis spectrophotometer in the wavelength range of 300-600 nm and a TEM (transmission electron microscope) analysis, the samples of colloidal silver formed were characterized. UV- Vis spectroscopy showed the appearance of sharp absorption maxima at wavelengths of 420-450 nm, proving the formation of silver nanoparticles. Using the PWHM method, the size of silver nanoparticles was estimated for all samples and ranged from 10 to 65 nm. The TEM analysis confirmed that they were spherical silver nanoparticles with an average particle size of 17-39 nm
Antimicrobial effect of vinification by-products : bachelor thesis
No full textTijekom procesa prerade grožđa i proizvodnje vina nastaju velike količine vrijednih nusproizvoda, poput komine grožđa, peteljki i vinskog taloga. Svi navedeni nusproizvodi pokazuju brojna biološka svojstva od kojih se izdvajaju antioksidacijska i antimikrobna aktivnost. Zbog navedenih svojstava nusproizvodi imaju potencijal za daljnju uporabu, a njihovim iskorištenjem doprinijet će se rješavanju problema sve veće količine organskog otpada nastalog tijekom postupka vinifikacije. Komina, kao količinski najzastupljeniji nusproizvod, bogata je bioaktivnim fitokemikalijama, osobito polifenolima. Međutim, vrlo često se vinski talog zanemaruje, a jednako je vrijedan nusproizvod jer je bogat fenolima, vitaminima i ugljikohidratima. U ovome radu ispitana je antimikrobna aktivnost ekstrakata taloga bijelog, crnog i rosé vina na patogene bakterije (Escherichia coli, Enterococcus faecalis, Listeria monocytogenes i Staphylococcus aureus) i bakterije kvarenja (Pseudomonas aeruginosa i Pseudomonas fragi). Korištene sorte su Malvasija dubrovačka i Plavac mali. Analize su provedene korištenjem tri različite metode: metodom određivanja minimalne inhibitorne koncentracije (eng. Minimal Inhibitory Concentration, MIC), metodom određivanja minimalne baktericidne koncentracije (eng. Minimal Bactericidal Concentration, MBC) i metodom difuzije u jažicama (engl. Well diffusion method). Dobiveni rezultati ukazuju na bolju antimikrobnu aktivnost ekstrakata vinskog taloga prema bakterijama kvarenja u odnosu na patogene bakterije. Najbolju aktivnost, odnosno najniže MIC i MBC vrijednosti (25,5 mg GAE/L) pokazao je uzorak bijelog vina dobiven maceracijom masulja u trajanju od 24 sata prije početka fermentacije i to prema bakterijama kvarenja P. aeruginosa i P. fragi.Grape processing and winemaking produce large quantities of valuable by-products, such as grape pomace, stems, and wine lees. All the mentioned by-products have numerous biological properties, among which the antioxidant and antimicrobial activity stand out. Due to the mentioned properties, the by- products have the potential for further use, and their utilization will help to solve the problem of the increasing amount of organic waste generated during the winemaking process. Pomace, the most represented by-product in terms of quantity, is rich in bioactive phytochemicals, especially polyphenols. Very often, however, the wine lees are overlooked, being an equally valuable by-product because they are rich in phenols, vitamins and carbohydrates. In this thesis, the antimicrobial activity of extracts of white, red and rosé wine less against pathogenic bacteria (Escherichia coli, Enterococcus faecalis, Listeria monocytogenes and Staphylococcus aureus) and spoilage bacteria (Pseudomonas aeruginosa and Pseudomonas fragi) was tested. The varieties used are Malvasija dubrovačka and Plavac mali. The analyzes were carried out using three different methods: the minimum inhibitory concentration (MIC), the minimum bactericidal concentration (MBC) and well diffusion method. The results obtained indicate a better antimicrobial activity of the wine less extracts determined by the MIC and MBC methods against spoilage bacteria compared to pathogenic bacteria. The best activity, i.e. the lowest MIC and MBC values (25.5. mg GAE/L) determined by all methods, was shown by a white wine obtained by maceration of grape must in a period of 24 hours before the start of fermentation, against to spoilage bacteria P. aeruginosa and P. fragi compared to the pathogenic bacteria tested
PROFILES OF VOLATILE COMPOUNDS OF ESSENTIAL OILS AND HYDROLATES OF ROCK SAMPHIRE (CRITIMUM MARITIMUM L.) OBTAINED BY DIFFERENT DISTILLATION PROCEDURES : bachelor thesis
No full textCilj ovog rada bio je istražiti učinke različitih metoda izolacije na kemijski sastav eteričnih ulja motra (Crithmum maritimum L.) kao i na sastav hlapivih spojeva prisutnih u hidrolatima koji zaostaju kao nusprodukt izolacije. Korištene su konvencionalne metode destilacije, vodena destilacija (HD) i parna destilacija (SD) te moderna „zelena“ metoda destilacije potpomognuta mikrovalovima (MHD). Izolacija hlapivih spojeva hidrolata izvršena je mikroekstrakcijom na čvrstoj fazi (HS-SPME). Za odvajanje i identifikaciju kemijskih sastojaka eteričnih ulja i hidrolata korišten je spregnuti sustav plinske kromatografije sa spektrometrijom masa (GC-MS). Eterično ulje dobiveno SD imalo je viši udio terpinena-4-ol, γ-terpinena i limonena nego li ulje izolirano HD i MHD. Sabinen je u najvišem udjelu bio prisutan u eteričnom ulju dobivenom MHD, dok je E-(β)-ocimen najviše zastupljen u eteričnom ulju dobivenom HD postupkom. U hidrolatu zaostalom nakon HD dominantni spojevi su 10-(acetilmetil)-3-karen i benzacetaldehid, dok je terpinen-4-ol s najvišim udjelom zastupljen u MHD hidrolatu. U hidrolatu dobivenom parnom destilacijom ističu se terpinen-4-ol, (Z)-sabinen hidrat i (E)-sabinen hidrat. Kemijski sastav hidrolata razlikuje se od sastava eteričnog ulja, kako po vrsti, tako i po broju različitih spojeva kojima eterična ulja u odnosu na hidrolate oskudijevaju. Iz ovog istraživanja može se zaključiti da je metoda izolacije imala velik utjecaj na kemijske profile eteričnog ulja motra, a posebice na profil spojeva hidrolata. Zbog svog vrijednog kemijskog sastava hidrolati kao glavni nusproizvod izolacije eteričnih ulja mogu se smatrati vrijednim izvorom bioaktivnih spojeva koji imaju veliku potencijal za daljnje korištenje u različitim industrijama.The aim of this work was to investigate the effects of different isolation methods on the chemical composition of the essential oils of rock samphire (Crithmum maritimum L.) and composition of the volatile compounds in the hydrolates, that remain as a by-products of essential oil isolation. Conventional distillation methods, water distillation (HD) and steam distillation (SD) were used, as well as a modern "green" method, microwave-assisted distillation (MHD). Isolation of volatile compounds from the hydrolates was performed by solid phase microextraction (HS-SPME). A coupled system of gas chromatography with mass spectrometry (GC-MS) was used to separate and identify the chemical components of the essential oils and hydrolates. The essential oils obtained by SD had higher levels of terpinene-4-ol, γ-terpinene and limonene than those obtained by HD and MHD. Sabinene was most abundant in the MHD essential oil, while E-(β)-ocimene was most abundant in the essential oil obtained by HD. In the HD hydrolate, 10-(acetylmethyl)- 3-carene and benzacetaldehyde dominated, while terpinen-4-ol was present with the highest proportion in the MHD hydrolate. In the SD hydrolate, terpinen-4-ol, (Z)-sabinene hydrate and (E)-sabinene hydrate stand out. The chemical composition of hydrolates differs from that of essential oil, both in terms of the type and number of different compounds that are absent in essential oils. From this study, it can be concluded that the isolation method has a great influence on the profile of rock samphire essential oils, and especially on the profile of compounds from hydrolates. Due to its valuable chemical composition, these by-products are valuable source of bioactive compounds with great potential for use in various industries
Rapid method for screening of glucosinolates from wild-growing Brassicaceae plants : master thesis
No full textU ovom radu proučavani su razgradni produkti glukozinolata šest samoniklih biljnih vrsta porodice Brassicaceae i to: Aurinia sinuata (L.) Griseb. (izverugana gromotulja), Aurinia leucadea (Guss.) K. Koch (jadranska rumenica), Bunias erucago (L.) (čunjasti repušac), Capsella rubella Reut. (sredozemna rusomača), Cardaria draba (L.) Desv. (streličasta grbica) i Sisymbrium officinale (L.) Scop. (strižuša). Ove biljne vrste rasprostranjene su u mediteranskom dijelu Hrvatske pa tako i na području park-šume Marjan (Split, Hrvatska). Razgradnja glukozinolata provedena je pomoću endogenog enzima mirozinaze. Izolacija razgradnih produkata glukozinolata (hlapljivih spojeva) provedena je HS-SPME metodom, a kemijski sastav i udio razgradnih produkata glukozinolata, kao i ostalih hlapljivih spojeva, određen je vezanom tehnikom plinska kromatografija-spektrometrija masa (GC-MS). Primjenom indirektne metode analize - HS-SPME/GC-MS, preko izolacije i identifikacije hlapljivih hidrolitičkih produkata, identificirani su glukozinolati u odabranim biljkama porodice Brassicaceae. Glavni glukozinolati jadranske rumenice su glukonapin i glukobrasikanapin. Glavni glukozinolati izverugane gromotulje su glukobrasikanapin i glukoberteroin. Broj, kao i udio razgradnih produkata glukozinolata, u vršnim parama čunjastog repušca je vrlo mali. Ipak, temeljem HS-SPME/GC- MS analize može se zaključiti da čunjasti repušac sadrži četiri glukozinolata, glukodehidroerucin, glukonapin, glukoerucin i glukokaparin. Glavni sastojci vršnih para sredozemne rusomače su alil- izotiocijanat i alil-tiocijanat, dakle glavni glukozinolat sredozemne rusomače je sinigrin. U vršnim parama streličaste grbice dominira 4-(metiltio)butil-izotiocijanat te se sa sigurnošću može zaključiti da je glavni glukozinolat streličaste grbice glukoerucin. S obzirom na najzastupljenije spojeve u vršnim parama strižuše, izopropil-izotiocijanat i sec-butil-izotiocijanat, može se zaključiti da su glavni glukozinolati strižuše glukoputranjivin i glukokohlearin.This work included research of glucosinolate degradation products from six wild-growing Brassicaceae plants: Aurinia sinuata (L.) Griseb., Aurinia leucadea (Guss.) K. Koch, Bunias erucago (L.), Capsella rubella Reut., Cardaria draba (L.) Desv. and Sisymbrium officinale (L.) Scop. These plant species are widespread in the Mediterranean part of Croatia as well as in the area of the Marjan Forest Park (Split, Croatia). Degradation of glucosinolates was performed using the endogenous enzyme myrosinase. Isolation of glucosinolate degradation products (volatile compounds) was performed by headspace solid-phase microextraction method (HS-SPME), and the chemical composition and content of glucosinolate degradation products, as well as other volatile compounds, was performed by gas chromatography-mass spectrometry technique (GC-MS). Using indirect analysis method, namely HS-SPME/GC-MS, via isolation and identification of volatile hydrolytic products, glucosinolates from selected wild-growing Brassicaceae plants were identified. The main glucosinolates of Aurinia leucadea are gluconapin and glucobrassicanapin. The main glucosinolates of Aurinia sinuata are glucobrassicanapin and glucoberteroin. Number and content of glucosinolate degradation products in headspaces from Bunias erucago is rather small. However, according to HS-SPME/GC-MS analysis, it can be assumed that Bunias erucago contain four glucosinolates, glucodehidroerucin, gluconapin, glucoerucin and glucocaparin. The main constituents in headspaces from Capsella rubella are allyl-isothiocyanate and allyl-thiocyanate, so the main glucosinolate of Capsella rubella is sinigrin. Dominanting compound in headspaces from Cardaria draba is 4-(methylthio)butyl-isothiocyanate so it can be concluded that the main glucosinolate in Cardaria draba is glucoerucin. Considering that the most abundant compounds in headspaces of Sisymbrium officinale are isopropyl-isothiocyanate and sec-butyl-isothiocyanate, it can be concluded that the main glucosinolates from Sisymbrium officinale are glucoputranjivin and glucocohlearin
Phytochemicals and antioxidants from the mediterranean diet : bachelor thesis
No full textMediteranska prehrana se smatra idealnim prehrambenim obrascem današnjice. Sve je više istraţivanja koja dokazuju blagotvorne učinke Mediteranske prehrane na ljudsko zdravlje i na prevenciju kroničnih nezaraznih bolesti. Mediteransku prehranu karakteriziraju nutritivno bogate namirnice poput voća, povrća, cjelovitih ţitarica, mahunarki, ribe, maslinovog ulja i crnog vina, a mediteranski stil ţivota povezuje se i s redovitom tjelesnom aktivnošću. Neupitno je da se stvaranjem i pridrţavanjem spomenutih mediteranskih navika osigurava bolji i kvalitetniji ţivot. Osim utjecaja Mediteranske prehrane na zdravlje, u ovom završnom radu obraĎene su i bitne komponente mediteranskih namirnica – fitokemikalije i antioksidansi. To su sastojci hrane koji su zasluţni za spomenute pozitivne učinke Mediteranske prehrane na ljudsko zdravlje. Provedenom anketom u eksperimentalnom dijelu rada istraţena je zastupljenost Mediteranske prehrane meĎu stanovnicima Splitsko-dalmatinske ţupanije.The Mediterranean diet is considered the ideal dietary pattern of today. There is a growing number of research demonstrating the positive effects of the Mediterranean diet on human health and the prevention of chronic non-communicable diseases. The Mediterranean diet features nutrient-dense foods such as fruits, vegetables, whole grains, legumes, fish, olive oil, and red wine, and the Mediterranean lifestyle is associated with regular physical activity. There is no question that creating and adhering to aforementioned Mediterranean habits, will ensure a better and higher quality of life. In addition to the effects of the Mediterranean diet on health, this undergraduate thesis also looks at the essential components of Mediterranean foods - phytochemicals and antioxidants. These are the food components that are responsible for the above mentioned beneficial effects of Mediterranean diet on human health. The survey conducted in the experimental part of the work investigated the representation of the Mediterranean diet among the inhabitants in Split-Dalmatia Country
Impact of SBT impeller speed on copper sorption on zeolite in a batch reactor : bachelor thesis
No full textOvim je radom ispitana kinetika sorpcije iona bakra na zeolitu NaX i utrošak snage miješanja pri četiri različite brzine vrtnje SBT miješala pri konstantnoj temperaturi suspenzije. Izvor iona bakra bila je otopina pripremljena otapanjem odgovarajuće mase Cu(NO 3 ) 2 ∙ 3H 2 O. Korištene su čestice zeolita NaX srednjeg promjera 0,0565 mm. Eksperimenti su provedeni u šaržnom reaktoru izrađenom od stakla opremljenome s razbijalima virova i SBT miješalom. Dobiveno vrlo dobro slaganje kinetičkih eksperimentalnih podataka s Blanchardovim, odnosno neslaganje istih s Weber -Morrisovim modelom, ukazuje da je reakcija najsporiji korak procesa, odnosno da ispitivana reakcija sorpcije iona bakra na zeolitu NaX prati kinetiku drugog reda.In this work, the sorption kinetics of copper ions on zeolite NaX and the mixing power consumption at four different SBT impellers speed and constant suspension temperature has been studied. The source of copper ions was a solution prepared by dissolving the appropriate mass of Cu(NO 3 ) 2 ∙ 3H 2 O. The zeolite NaX particles with a mean particle diameter of 0.0565 mm were used. The experiments were carried out in a glass batch reactor equipped with baffles and the SBT impeller. Very good agreement of the kinetic experimental data with Blanchard's and deviation from the Weber - Morris model were obtained indicating that the reaction is the slowest step of the process and that the reaction of copper ion sorption on zeolite NaX follows the second order kinetics
Preparation and characterization of polymer packaging film containing rosemary extract : diploma thesis
No full textGlavni cilj ovog rada bio je pripremiti kompozitne filmove od polietilena (PE) i polipropilena (PP) s ekstraktom ružmarina (ER) ekstruzijom kojom su dobiveni filmovi (PE/ER i PP/ER). Za određivanje interakcija polimera i ekstrakta u kompozitu korištena je infracrvena spektroskopija s Fourierovom transformacijom (FT-IR). Za otkrivanje utjecaja ekstrakta ružmarina na toplinske karakteristike polimerne matrice korištena je diferencijalna pretražna kalorimetrija (DSC). Na temelju karakterističnih PE i PP apsorpcijskih vrpci, njihovog intenziteta, oblika i položaja može se zaključiti da dodatak ER nije utjecao na strukturu polimerne matrice. DSC krivulje su pokazale da karakteristični prijelaz taljenja i kristalizacije polimerne matrice praktički ostaju nepromijenjeni nakon dodavanja ER. Time je ostvaren glavni cilj ovog rada.The main objective of this work was to prepare the composite films of the polyethylene (PE) and polypropylene (PP) with rosemary extract (ER) via hot melt extrusion (PE/ER and PP/ER). In order to determine the interactions of polymer and extract in the composite the Fourier transform infrared spectroscopy (FT-IR) was utilized. Differential scanning calorimetry (DSC) was used to detect influence of ER on the thermal characteristics of polymer matrix. Based on the characteristic PE and PP absorption bands, their intensity, shape and position it can be concluded that ER addition had no effect on the structure of polymer matrix. DSC curves revealed that characteristic melting and crystallization transition of polymer matrix practically remained unchanged upon ER addition. Hence, the main goal of this work was achieved