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U radu je ispitan utjecaj prihrane s višestruko povećanom koncentracijom cinka na fenolni sastav lista maslina uzgojenih u hidroponskom sustavu tijekom deset mjeseci. Pokus je proveden u plasteniku na jednogodišnjim sadnicama masline sorte Istarska bjelica. Sadnice su prihranjivane standardnom Hoaglandovom hranjivom otopinom bez cinka (0 μM) i hranjivom otopinom koja je imala povećanu koncentraciju cinka (32 μM). Analiza fenolnog sastava lišća provedena je tekućinskom kromatografijom visoke djelotvornosti s UV-VIS detekcijom. Prihrana s višestruko povećanom koncentracijom cinka rezultirala je statistički značajno većim vegetativnim prirastom sadnica maslina i povećanjem ukupnih identificiranih fenolnih tvari u lišću, za 48% odnosno 30% u odnosu na sadnice sa prihranom bez cinka. Lišće maslina tretirano hranjivom otopinom s povećanom koncentracijom cinka sadržavalo je 1,5 puta veći maseni udio oleuropeina te 1,3 puta više luteolin-7-O-glukozida u odnosu na sadnice koje su bile na prihrani bez cinka. Prihranom masline cinkom dobiveno je lišće veće prehrambene vrijednosti tj. bogatije fenolnim tvarima, osobito oleuropeinom., In this thesis, the effect of fertilization with a multiply increased zinc concentration on olive plantlets leaf phenolic composition in the hydroponic system during a 10-months period has been investigated. The experiment was conducted in a greenhouse with one-year old olive plantlets of the olive cultivar Istarska bjelica. Olive plantlets were grown in the Hoagland nutrient solution with omission of zinc (0 μM) and nutrient solution with increased zinc concentration (32 μM). The phenolic composition of olive leaves was determined by high performance liquid chromatography with a UV/VIS detector. In zinc treated olive plantlets, vegetative growth and total identified phenols increased statistically significantly, by 48% and by 30% respectively, in relation to olive plantlets without zinc fertilization. Furthermore, olive leaf treated with a nutrient solution with a multiply increased zinc concentration contained 1.5-fold higher mass fraction of oleuropein and 1.3-fold higher luteolin-7-O-glucoside compared to olive plantlets with omission of zinc. Fertilization treatment with zinc resulted in higher nutritional values of leaves due to higher amounts of phenols, especially of oleuropein.

U radu je ispitan utjecaj monomera i oligomera poliedarskih oligomernih silseskvioksana (POSS) na dinamiku lanaca epoksidne mreže temeljene na diglicidil eteru bisfenola A (DGEBA) i poli(oksipropilen)diaminu (Jeffamine D2000). Staklišta čiste epoksidne matrice i ispitivanih nanokompozita određena su metodom razlikovne pretražne kalorimetrije (DSC). Promjene u dinamici lanaca polimera ispitane su metodom spinske probe u elektronskoj spinskoj rezonanciji (ESR). Rezultati pokazuju da nakon ugradnje monomera POSS ne dolazi do značajnijeg ojačanja epoksidne matrice. Pri većem udjelu molekula POSS dolazi do njihove agregacije čime se stvaranju šupljine u polimernoj matrici. Zbog toga se povećava gibljivost lanaca polimera te smanjuje staklište ispitivanih nanokompozita. Nasuprot tome, prisutnost oligomera POSS uzrokuje snažne interakcije sa epoksidnom matricom što se očituje velikim porastom staklišta i znatnim smanjenjem mobilnosti lanaca polimera. In this thesis, the influence of monomers and oligomers of polyhedral oligomeric silsesquioxanes (POSS) on the dynamics of epoxy network based on bisphenol A diglycidyl ether (DGEBA) and poly(oxypropylene)diamine (Jeffamine D2000) has been investigated. The glass transition temperature of pure epoxy matrix and investigated nanocomposites was determined by differential scanning calorimetry (DSC). Changes in polymer chain dynamics were investigated by spin probe electron spin resonance spectroscopy (ESR). The results show that the incorporation od POSS monomers does not lead to a significant reinforcement of the epoxy matrix. Higher amount of POSS molecules causes their aggregation and formation of cavities in the polymer matrix. As a result, the mobility of polymer chains increases and the glass transition temperature of the investigated nanocomposites decreases. In contrast, the presence of POSS oligomer causes strong interactions with epoxide matrix which is reflected in the large increase of glass transition temperature and significant reduction in the mobility of polymer chains.