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Calixarene derivatives in theranostics : bachelor thesis
No full textS ciljem da se ispita kompleksacijski afinitet nesimetrično supstrituiranog amidnog difenilantracenskog derivata kaliksarena 5,11,17,23-tetra-tert-butil-25-(9,10-difenilantracen-2-iloksietoksi)- 26,27,28-tris(N,N-dietil-karbamoilmetoksi)kaliks[4]arena, L, prema organskim bojama - rodaminu B, auraminu O i fluoresceinu te aktivnoj tvari – timokinonu, proveden je niz spektrofotometrijskih titracija u acetonitrilu. Određene su i konstante stabilnosti odgovarajuć ih kompleksa koje ukazuju na nastanak relativno stabilnih kompleksa derivata kaliks[4]arena L s istraživanim bojama, pri čemu je spoj L pokazao najveći afinitet prema auraminu O. S druge strane, s timokinonom nije došlo do vezanja zbog njegove strukturne nekomplementarnosti s veznim mjestom liganda. Iako kompleksu [L- fluorescein] nije bilo moguće odrediti konstantu stabilnosti, iz eksperimentalnih je podataka bio vidljiv nastanak kompleksa, te je njena vrijednost procijenjena kao niža u odnosu na odgovarajuće konstante za rodamin B i auramin O. Ispitani derivat kaliksarena demonstrirao je dobre receptorske sposobnosti veznog mjesta koje se sastoji od tercijarnih amidnih skupina i difenilantracenske skupine, pa je za očekivati da bi njegov vodotopivi analog imao velik potencijal u teranostici.In order to investigate the complexation affinity of the asymmetrically substituted amide diphenylanthracene derivative of calixarene 5,11,17,23-tetra-tert-butyl-25-(9,10-diphenylanthracene-2- yloxyethoxy)-26,27,28-tris(N,N-diethyl-carbamoylmethoxy) calix[4]arene, L, towards the organic dyes – rhodamine B, auramine O and fluorescein and the active compound – thymoquinone, a series of spectrophotometric titrations in acetonitrile were carried out. The stability constants of the corresponding complexes were determined and their values indicated that relatively stable complexes of calix[4]arene derivatives L with the studied dyes were formed, with compound L showing the highest affinity for the binding of auramine O. On the other hand, the complex with thymoquinone did not form under the experimental conditions used, due to its structural incompatibility with the ligand's binding site. Although the value of the stability constant for [L-fluorescein] complex could not be determined, there was experimental evidence of the complex formation and its value was estimated to be lower than the corresponding constants for rhodamine B and auramine O. Since the studied calixarene derivative demonstrated good receptor properties of the binding site composed of tertiary amide groups and a diphenylanthracene group, it can be expected that its water-soluble analogue should have great potential for applications in theranostics
GREEN FACULTY LIBRARY ZELENA KNJIŽNICA FAKULTETA
No full textSvjesni smo činjenice da se današnji svijet suočava s neviđenim posljedicama klimatskih promjena, gdje su pojmovi zagađenje, e-otpad i iscrpljivanje prirodnih resursa postali dio našeg svakodnevnog života. Pojam zelenih knjižnica može biti višeznačan i s jedne strane se promatrati kroz aspekt zelene i održive gradnje samih zgrada knjižnice, ali i kroz koncept zelenih programa, informacijskih usluga i zbirki te usvajanje novih inovativnih i pametnih tehnologija koje se mogu integrirati u funkcioniranje knjižnica. Pri tome visokoškolski knjižničari svojim aktivnostima opismenjavanja o ekologiji i održivom razvoju mogu potaknuti studente i znanstveno-nastavno osoblje na održivo djelovanje u cilju zaštite okoliša te njihovo promicanje takvih ideja u vlastitoj praksi. Cilj ovog izlaganja je pokazati uključivost visokoškolskih knjižnica kao potencijalnih partnera u promicanju održivog razvoja i zaštite okoliša. Sukladno tome, predstaviti će se primjeri dobre prakse zelenih knjižnica u svijetu i Hrvatskoj kojima se svojim aktivnostima priključila i knjižnica Kemijsko-tehnološkog fakulteta u Splitu
Modification of polymer electrolytes based on poly(ethylen oxide) and lithius bis(oxalato)borate to improve ionic conductivity : bachelor thesis
No full textOvaj rad bavi se ispitivanjem utjecaja dodatka litijevog montmorilonita (LiMMT) na toplinske prijelaze (staklište i talište) i kristalnost poli(etilen-oksida). Primijenjene su metode diferencijalne pretražne kalorimetrije (DSC) i infracrvene spektroskopije s Fourierovom transformacijom (FT-IR). LiMMT pripremljen je metodom ionske izmjene iz prirodnog montmorilonita, a polimerni nanokompoziti PEO10/LiMMT/LiBOB s masenim omjerima PEO10/LiMMT 95/5, 90/10, 80/20, 70/30, 60/40 pripremljeni su metodom interkalacije iz taljevine. Sol litijevog bis(oksalato)borata (LiBOB) dodana je u omjeru 1:8 (Li : kisik iz PEO) s ciljem ostvarivanja dovoljne koncentracije nositelja naboja u elektrolitu. Metodom diferencijalne pretražne kalorimetrije (DSC) ispitivan je utjecaj LiMMT-a na toplinske prijelaze (staklište i talište) i kristalnost PEO-a. Utvrđeno je da dodatak LiBOB-a u potpunosti narušava kristalnost uzoraka do 30 mas.% LiMMT, a uzorci s 30 i 40% LiMMT-a pokazali su kristalnu fazu s talištem koje je niže od tališta čistog PEO-a. Metodom infracrvene spektroskopije s Fourierovom transformacijom (FT-IR) ispitivan je utjecaj LiMMT-a na strukturu PEO-a. Utvrđeno je da se dodatkom LiMMT-a narušava spiralna konformacija kristalne faze izvornog PEO-a.This paper examines the impact of lithium bis(oxalato)borate (LiBOB) filler on thermal transitions (glass transition temperature, melting temperature) and crystallinity od poly(ethylene-oxide). Differential scanning calorimetry (DSC) and Fourier Transformation Infrared Spectroscopy (FT-IR) have been applied. LiMMT was prepared by ion exchange method from natural montmorillonite, and polymeric nanocomposites PEO10/LiMMT/LiBOB with different weight ratios PEO/LiMMT 95/5, 90/10, 80/20, 70/30 and 60/40 were prepared by the melt intercalation method. Salt of lithium bis(oxalato)borate (LiBOB) was added in a ratio of (1:8 Li : oxygen of ether) to achieve a sufficient concentration of the charge carrier. Differential scanning calorimetry (DSC) analysis investigate the influence od LiMMT on the thermal transitions (glass transition temperature, melting temperature) and crystallinity of PEO10. It was found that the addition of LiBOB completely destroys the crystallinity of the samples up to 30 % of LiMMT. Samples with 30 % and 40 % of LiMMT showed a crystalline phase with a melting point that is lower than the melting point of original PEO. Fourier Transformation Infrared Spectroscopy (FT-IR) investigate the influence LiMMT on the PEO10 structure. It was found that the addition of LiMMT causes distortion of the spiral conformation of the crystalline phase of the original PEO
Determination of the limiting concentration of triple ions formation in solutions of ammonium bromide : bachelor thesis
No full textKonduktometrijskom metodom određena je granica nastajanja trostrukih iona u otopinama amonijevog bromida i 90 %-tnog butan-2-ola pri temperaturi od 25°C. Za obradu podataka korišten je kemijski model provodnosti utemeljen na jednadžbi za provodnost Fuoss-Hsia. Iz koncentracijske ovisnosti elektrolitne vodljivosti razrijeđenih otopina izračunate su granična molarna provodnost i termodinamička konstanta ravnoteže za ionsku asocijaciju te granična molarna provodnost trostrukih iona i termodinamička konstanta ravnoteže za reakciju nastajanja trostrukih iona.The limiting concentration of triple ions formation in solutions of ammonium bromide and 90% butan-2-ol at a temperature of 25° C was determined by the conductometric method. A chemical conductivity model based on the Fuoss-Hsia conductivity equation was used to process the data. From the concentration dependence of the electrolyte conductivity of dilute solutions, the limiting molar conductivity and thermodynamic equilibrium constant for ionic association and the limiting molar conductivity of triple ions and the thermodynamic equilibrium constant for the reaction of triple ion formation were calculated
Behaviour and attitudes of consumers towards olive fruit products : master thesis
No full textMaslina (Olea europaea L.) je jedna od najznačajnijih biljnih kultura Mediterana i smatra se najstarijom kultiviranom biljnom vrstom. Uzgoj maslina u Republici Hrvatskoj seže u davnu prošlost i za stanovnike ovih područja maslina predstavlja puno više od samog stabla koje donosi plodove. Ona je simbol mira, opstojnosti, plodnosti i mudrosti, a glavni proizvod masline, maslinovo ulje bilo je i ostalo temelj za život brojnih obitelji. Posljednjih godina maslinarstvo u Hrvatskoj bilježi znatan rast, a kvaliteta maslinovih ulja je u samom vrhu među vodećim maslinarskim zemljama. Cilj ovog rada bio je ispitati upoznatost potrošača s proizvodima ploda masline, utvrditi mišljenja i stavove obzirom na pojedine proizvode te prikazati najznačajnije čimbenike koji utječu na donošenje odluke o kupnji i konzumaciji istih. Najveći naglasak je stavljen na maslinovo ulje te konzervirane stolne masline. Za potrebe rada provedeno je anketno istraživanje na području Republike Hrvatske. Podaci su prikupljeni anketnim ispitivanjem 180 ispitanika putem on-line upitnika. Prema rezultatima ankete potrošači najveću važnost pri kupnji maslina i maslinovog ulja pridaju kvaliteti i cijeni proizvoda. Od proizvoda ploda masline uglavnom konzumiraju maslinovo ulje pri čemu preferiraju ulja domaćih proizvođača. Od ostalih proizvoda od masline većina konzumira konzervirane masline, dok mali dio poznaje i konzumira druge proizvode od maslina kao što su primjerice paste odnosno tapenade. Rezultati dobiveni u ovom istraživanju mogu biti od pomoći proizvođačima u razvijanju odgovarajućih marketinških strategija kroz popularizaciju i promidžbu proizvoda ploda masline s ciljem povećanja njihove gospodarske vrijednosti.Olive (Olea euroapea L.) is one of the most famous plants of the Mediterranean area and is considered the oldest cultivated plant species. The cultivation of olive trees in the Republic of Croatia dates back to the ancient times, and for the inhabitants of these areas, olives represent much more than just a tree that bears fruit. Olive tree is a symbol of peace, ability, fertility and wisdom, and the main product of the olive tree, olive oil, was and remains the basis for the life of many families. In recent years, olive-growing in Croatia significantly increased and the quality of olive oils is highly positioned among main olive-growing countries. The aim of this paper was to examine consumer’s familiarity with olive products, to determine opinions and attitudes regarding individual olive fruit products, and to present the most significant factors that influence on the purchasing decision and consuming them. The greatest emphasis is placed on olive oil and table olives. For the purposes of this work, a survey was conducted in the territory of the Republic of Croatia. The data were collected by surveying 180 respondents through an online questionnaire. According to the results of the survey, consumers attach the greatest importance when buying olives and olive oil to the quality and the price of the product. Considering the olive fruit products consumers mainly consume olive oil, preferring the oils of local producers. Among other olive fruit products, majority of them consume table olives, while only few of them are familiar with other olive fruit products such as pastes or tapenade. The results obtained in this study can be helpful to producers in developing appropriate marketing strategies through the popularization and promotion of olive fruit products with the aim of increasing their economic value
Volatile compounds of Pelinkovac liquer : master thesis
No full textPelinkovac je jako alkoholno piće koje se tradicionalno proizvodi u Republici Hrvatskoj. Pripada kategoriji biljnih likera dobiven aromatiziranjem etilnog alkohola poljoprivrednog podrijetla maceratima aromatičnog bilja u kojima po sastavu i količini dominira biljka pelin (Artemisia absinthium L.), uz komorač (Foeniculum vulgare L.), kadulju (Salvia officinalis L.) i mentu (Menta piperita L.), koji proizvodu daju prepoznatljiva i karakteristična organoleptička svojstva. Cilj ovog rada je bio usporediti aromatični profil pet vrsta likera Pelinkovca prisutnih na tržištu republike Hrvatske. Hlapljivi spojevi izolirani su pomoću mikroekstrakcije vršnih para na krutoj fazi (HS-SPME), a analizirani vezanim sustavom plinska kromatografija-masena spektrometrija (GC-MS). Analiziranjem dobivenih rezultata utvrđen je različiti sastav hlapljivih spojeva među ispitanim uzorcima. U uzorcima A, B i E dominira trans-anetol (36,10 %, 43,21 % i 39,20 %), u uzorku C limonen (52,82 %) te u uzorku D p-menton (25,76 %). Utvrđene razlike u aromatičnom profilu upućuju na specifičnosti pojedinog proizvođača u odabiru aromatičnog bilja i tehnološkog procesa proizvodnje.Pelinkovac is strong alcoholic beverage that is traditionally produced in Croatia. It belongs to the category of herbal liqueurs, obtained by aromatizing ethyl alcohol of agricultural origin with macerates of aromatic plants in which the wormwood plant (Artemisia absinthum L.) dominates, along with fennel (Foeniculum vulgare L.), sage (Salvia officinalis L.) and mint (Menta piperita L.), which give the products recognizable and characteristic organoleptic properties. The aim of this study was to compare the aromatic profile of five types of Pelinkovac liqueur present on the market of the Republic of Croatia. Volatile compounds were isolated using headspace solid phase microextraction (HS-SPME), and analyzed by a coupled gas chromatography-mass spectrometry (GC-MS) system. The analysis of the obtained results revealed a different composition of volatile compounds among the tested samples. Trans anethole was the dominat compound in samples A, B and E (36,10 %, 43,21 % and 39,20 %), while in sample C it was limonene (52.82 %) and in sample D p-menthone (25, 76 %). The established differences in the aromatic profile point to the specifics of each producer in the selection of aromatic herbs and the technological process of production
Determination of iron concentration in enriched sprouts of Brassica oleracea plant by atomic absorption spectroscopy : bachelor thesis
No full textAtomska apsorpcijska spektroskopija je analitička tehnika koja omogućava lako kvantitativno određivanje metala u uzorku. U ovom radu je prikazano zasićenje biljke Brassice oleraceae željezom te njezino razvijanje pod utjecajem većih količina željeza. Analizom je utvrđeno da prilikom prezasićenja sjemena željezom neće doći do razvoja biljke.Atomic absorption spectroscopy is an analytical technique that enables easy quantitative determination of metals in a sample. This paper shows the saturation of the Brassica oleraceae plant with iron and its development under the influence of larger amounts of iron. The analysis determined that when the seed is oversaturated with iron, the plant will not develop
INFLUENCE OF ULTRASOUND AMPLITUDE ON BORAX NUCLEATION KINETICS IN A BATCH CRYSTALLIZER AT DIFFERENT COOLING RATES : diploma thesis
No full textCilj ovog rada bio je ispitati utjecaj amplitude ultrazvuka na kinetiku nukleacije dinatrijevog tetraborat dekahidrata (boraksa) tijekom procesa šaržne kristalizacije pri različitim brzinama hlađenja. Kristalizacija boraksa se provodila iz matične otopine zasićene pri 30 °C hlađenjem do temperature od 10 °C u šaržnom kristalizatoru s miješanjem uz primjenu radijalnog turbinskog miješala s četiri ravne lopatice, tzv. SBT miješalo, pri brzini vrtnje potrebnoj za postizanje stanja potpune suspenzije kristala (N=N JS ). Kako bi se sagledao utjecaj amplitude ultrazvuka na kinetiku nukleacije ispitivanja su se provodila pri četiri amplitude snage ultrazvuka u rasponu od 0 do 30 % te pri četiri brzine hlađenja matične otopine od 4 do 10 °C h -1 . Početak nukleacije određivan je vizualno, dok se promjena koncentracije matične otopine pratila refraktometrijskom metodom. Po završetku procesa kristalizacije izvršena je granulometrijska analiza produkta metodom laserske difrakcije za zadane brzine hlađenja matične otopine pri amplitudi ultrazvuka od 20 %. Za sve ispitivane uvjete određena je snaga privedena sustavu uslijed miješanja i ultrazvučnog djelovanja. Analizom eksperimentalnih rezultata uočeno je da je u svim sustavima prisutno suženje metastabilne zone s povećanjem amplitude ultrazvuka i sa smanjenjem brzine hlađenja te je definirana funkcionalna ovisnost širine metastabilne zone o navedenim veličinama. Utvrđeno je da je u svim ispitivanim sustavima jednaka vrijednost prividnog reda nukleacije, dok se konstanta brzine nukleacije povećavala s amplitudom ultrazvuka, odnosno s privedenom snagom. Također je utvrđeno da je u svim sustavima nukleacija započinjala mehanizmom primarne heterogene nukleacije, a njezina brzina smanjivala se povećanjem amplitude ultrazvuka i smanjenjem brzine hlađenja matične otopine. Konačno, bez obzira na brzinu hlađenja u sustavima s ultrazvučnim djelovanjem dobiveni su kristali sličnih svojstava s obzirom na vrijednosti srednjeg volumnog promjera i njegove standardne devijacije. U ovim sustavima vrijednosti navedenih veličina su značajno manje od onih dobivenih u sustavu bez ultrazvučnog djelovanja pri brzini hlađenja od 6 °C h -1 .The aim of this thesis was to examine the influence of ultrasound amplitude on nucleation kinetics of disodium tetraborate decahydrate (borax) during the batch crystallization at different cooling rates. Borax crystallization was carried out from a mother liquor saturated at 30 °C by cooling to a temperature of 10 °C in a batch crystallizer stirred by a radial turbine impeller with four flat blades, so called SBT, at the impeller speed required to achieve a state of complete crystals suspension (N = N JS ). In order to define the influence of ultrasound amplitude on nucleation kinetics, tests were performed at four amplitudes of ultrasonic power in the range of 0 to 30%, and at four cooling rates from 4 to 10 °C h -1 .The onset of nucleation was determined visually, while the change in the concentration of the mother liquor was monitored by refractometric method. Upon completion of the crystallization process, granulometric analysis of the product was performed by laser diffraction for given cooling rates of the mother liquor at an ultrasonic amplitude of 20%. For all tested conditions the power brought to the system due to mixing and ultrasonic irradiation was determined.The experimental results showed narrowing of the metastable zone width with increasing ultrasound amplitude and decreasing cooling rate, also the functional dependence of the metastable zone width on these values was defined. It was found that in all systems the value of the nucleation order is the same, while the nucleation rate constant increases with the ultrasound amplitude, i.e. with the power dissipated to the system. It was also found that in all systems the nucleation started by the primary nucleation mechanism, while its rate decreased by increasing the ultrasound amplitude and decreasing the cooling rate. Finally, regardless of the cooling rate in ultrasonic systems, the crystals of similar properties are obtained regrding values of the mean volume diameter and its standard deviation. In the ultrasonic systems, these values are significantly lower than those obtained in the system without ultrasonic irradiation at a cooling rate of 6 °C h - 1
Phenolic composition of different parts of ripe and unripe avocado : bachelor thesis
No full textAvokado kao klimakterijsko voće dozrijeva nakon berbe te za posljedicu toga sadrži različite koncentracije antioksidativnih komponenti, ključnih u zaštiti ljudskog organizma od negativnog utjecaja slobodnih radikala, u zrelom i nedozrelom plodu. Cilj ovog istraživanja bio je usporediti koncentracije fenola i flavonoida u ispitivanim uzorcima zrelog i nedozrelog ploda avokada. Nakon postupka ekstrakcije, uklanjanja etanola i liofilizacije dobiveni su uzorci podvrgnuti spektrofotometrijskim metodama pomoću kojih su koncentracije navedenih antioksidansa izmjerene. Najveći udio fenola pronađen je u sjemenci zrelog avokada, dok flavonoida u sjemenci nezrelog avokada. Najmanje koncentracije fenola i flavonoida zabilježene su upravo u pulpi, dijelu ploda koji se najviše konzumira u čovjekovoj prehrani.Avocado, as a climacteric fruit ripens after harvest and therefore contains different concentrations of antioxidant components in ripe and unripe fruits, which are crucial for protecting the human body from the negative effects of free radicals. The aim of this study was to compare the concentrations of phenols and flavonoids in the studied samples of ripe and unripe avocado fruit. After the extraction process, ethanol removal and freeze-drying, the obtained samples were subjected to spectrophotometric methods that measured the concentrations of these antioxidants. The highest level of phenols was found in ripe avocado seed, while flavonoids in unripe avocado seed. The lowest concentrations of both antioxidants were found in the pulp, the part of the fruit most consumed in the human diet
Development of a carbon paste ion sensor for the determination of acebutolol with various modifiersand tris(2-ethylhexyl)phosphate as binder : diploma thesis
No full textPripremljen potenciometrijski senzor na bazi paste od ugljika korišten je za odreĊivanje acebutolola hidroklorida koji je u širokoj upotrebi za lijeĉenje hipertenzije i aritmije. Elektroda je namijenjena za odreĊivanje ovog -blokatora u koncentracijskom podruĉju od 3,16 M do 3,16 M pri pH =5 u realnim uzorcima. Pripremljene su i testirane 22 membrane izraĊene dodatkom razliĉitog udjela ugljika, TEPH-a i IAC-a. Dakle, zajedniĉko svim membranama je što su pripremljene dodatkom istog veziva tris(2-etilheksil)fosfata. Najbolje odzivne karakteristike je pokazala pasta 11 pripremljena od 53,20% grafita, 43,60% TEPH-a, 2,90% IAC-a uz dodatak 0,30% NaTPB-a kao soli. Takva elektroda pokazala je Nernstov nagib od 54,76 mV po koncentracijskoj dekadi, a za uspostavu stabilnog odziva bilo je potrebno 60 sekundi. Ostale pripravljene membrane pokazale su promjenu potencijala po koncentracijskoj dekadi od 129 do 423 mV u linearnom dinamiĉkom podruĉju od 3,16 M do 3,16 M do koncentracija acebutolola.The prepared carbon paste-based potentiometric sensor was used to determine the concentration of acebutolol hydrochloride which is widely used for the treatment of hypertension and arrhythmia. This electrode is used for the determination of the -blocker in the concentration range of 3,16 M to 3,16 M at pH=5 in real samples. 22 membranes, supplemented with different proportions of carbon, TEPH and IAC were prepared and tested. Moreover, all the used membranes contained the same biner tris (2-ethylhexyl) phosphate, in their composition. The best response characteristics were indicated by paste 11 which consisted of 53.20% graphite, 43.60% TEPH, 2.90% IAC with the addition of 0.30% NaTPB as the salt. Such an electrode showed a Nernst slope of 54.76 mV per concentration decade. Moreover, it took 60 seconds to establish a stable response. The other prepared membranes showed a potential change of 129 to 423 mV per concentration decade in a linear dynamic range of 3,16 M to 3,16 M of acebutolol concentrations