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This doctoral thesis is focused on the rational design of novel nanostructured biosensing materials and their application in medical diagnostics, in the field of biological aging. Aging and age-related diseases are the consequences of the accumulation of oxidative damage to proteins. One way to measure protein oxidation is to determine levels of protein carbonyls. Currently, protein carbonylation is detected and quantified with 2D gel-based methods using specific fluorescent dyes coupled with hydrazide that reacts with protein carbonyls. However, commonly used dyes suffer from moderate biocompatibility, solubility and photostability. To improve the specificity and sensitivity necessary for diagnostics and prognostic purposes, there is room for advanced strategies. Luminescent ligated gold nanoclusters (AuNCs), composed of several to up to a few hundred Au atoms and protected by thiolated ligands, exhibit quantum confinement effects and molecule-like properties with tunable emission. Also, their impressive nonlinear optical properties make them promising candidates for various bio-imaging techniques such as multiphoton excited fluorescence microscopy. The main objective of this doctoral thesis was to detect protein carbonylation by optical methods using functionalized gold nanoclusters from 2D gels to in vitro. Research presented in this thesis is organized in four chapters. In the first chapter, the current strategies used to analysis carbonylation in living materials will be briefly addressed as well as the potential of using nanoclusters obtained at the atomic precision for detection of carbonyl groups on proteins by optical methods. Experimental chapter describes in detail the techniques crucial to characterize nanoclusters specifying atomic precision by mass spectrometry, measurements of their optical properties (linear and nonlinear), and other characterization methods: sizing techniques, microscopies used to visualize signal from gels and the NCs inside the cells, chemical and biological protocols for carbonylation. The third chapter is devoted to describing the numerous synthesis approaches (most of them were unsuccessful) that have conducted us to develop functionalized gold nanoclusters as luminescent probes for protein carbonylation detection. This research was done using the model lysozyme protein. This thesis outlines the development of glutathione gold NCs and its functionalization as efficient targets towards carbonylation, gels composition modification for studying both proteins and nanoclusters, proteomic approaches to understand the amount and the sites of carbonylation of the lysozyme, and the proof-of-principles of using NCs as luminescent probes for protein carbonylation detection with gels. Last chapter describes the strategies that were conducted to render nanoclusters appealing for cell bioimaging. For the first time, bioimaging measurements using multiphoton confocal microscopy were demonstrated in Lyon using silver based NCs internalized inside the cells. Thesis epilogue highlights the current stage of this project, the current limitations as well as some perspectives to render nanoclusters serviceable for biologists in particular in the context of biological aging., Ovaj doktorski rad usmjeren je na dizajn novih nanostrukturiranih biosenzoričkih materijala za primjenu u medicinskoj dijagnostici, posebice u području biološkog starenja. Starenje i bolesti povezane sa starenjem posljedica su nakupljanja oksidativnog oštećenja proteina. Jedan od načina mjerenja oksidacije proteina jest određivanje razine karbonilacije proteina. Trenutačno se karbonilacija proteina detektira i kvantificira metodama koje se temelje na 2D gelovima uz korištenje specifičnih fluorescentnih boja vezanih na hidrazid, koji reagira s karbonilima proteina. Međutim, boje imaju nisku biokompatibilnost, nisku topljivost i umjerenu fotostabilnost. Kako bi se poboljšala potrebna specifičnost i osjetljivost na oksidativna oštećenja, potrebno je pronaći naprednije strategije. Nanoklastere zlata (AuNC), sastavljene od nekoliko do par stotina atoma zaštićenih tioliranim ligandima, karakteriziraju kvantni učinci te molekularna svojstva s kontroliranom fotoluminiscencijom. Štoviše, impresivna nelinearna optička svojstva ovih nanoklastera čine ih obećavajućim kandidatima za razne tehnike bio-oslikavanja kao što je multifotonska fluorescentna mikroskopija. Glavni cilj ovog doktorskog rada bio je identificirati karbonilaciju proteina optičkim metodama korištenjem funkcionaliziranih nanoklastera zlata, od 2D gelova do in vitro istraživanja. Ovaj rad podijeljen je u četiri poglavlja. U prvom poglavlju ukratko su prikazane trenutne strategije koje se koriste za analizu karbonilacije u živim organizmima i potencijal korištenja nanoklastera dobivenih atomskom preciznošću, u svrhu detekcije karbonilnih skupina na proteinima optičkim metodama. U eksperimentalnom dijelu, opisane su osnovne tehnike za karakterizaciju nanoklastera kao i pojam atomske preciznosti masenom spektrometrijom, mjerenje optičkih svojstva (linearnih i nelinearnih) kao i druge metode karakterizacije: tehnike za modificiranje veličine, mikroskopije korištene za vizualizaciju signala gelova i nanoklastera unutar stanica, te kemijske i biološke protokole za karbonilaciju. Treće poglavlje posvećeno je opisu brojnih sintetskih pristupa (od kojih je većina bila neuspješna) koji su nas doveli do razvoja funkcionaliziranih nanoklastera zlata kao luminiscentnih proba za detekciju karbonilacije proteina. U ovom radu korišten je model proteina lizozima. Posebice, opisan je razvoj zlatnih nanoklastera zaštićenih molekulama glutationa i njihova funkcionalizacija za učinkovito označavanje mjesta karbonilacije. Nadalje, pojašnjena je modifikacija sastava gelova za proučavanje proteina i nanoklastera, metoda proteomike za razumijevanje količine i mjesta karbonilacije lizozima te “dokaz principa” za upotrebu nanoklastera kao luminiscentnih probi za detekciju karbonilacije proteina na gelovima. Posljednje poglavlje opisuje strategije provedene kako bi nanoklasteri bili primjenjivi i učinkoviti u staničnom bio-oslikavanju. Po prvi puta, bio-oslikavanja multifotonskom konfokalnom mikroskopijom demonstrirana su u Lyonu korištenjem nanoklastera srebra unesenih unutar stanica. Epilog ovog doktorskog rada donosi pregled postignutog napretka istraživanja, trenutna ograničenja kao i neke nove perspektive koje bi nanoklastere usmjerilo većoj primjenjivosti za biologe, posebno u kontekstu staničnog starenja., Ce travail de doctorat porte sur la conception de nouveaux nanomatériaux et leur application au diagnostic médical, en particulier dans le domaine du vieillissement. Le vieillissement et les maladies liées à l'âge sont les conséquences de l'accumulation de dommages oxydatifs sur les protéines. Une façon de mesurer l'oxydation des protéines est de déterminer les niveaux de carbonyles des protéines. À l'heure actuelle, la carbonylation des protéines est détectée et quantifiée par des méthodes basées sur des gels 2D utilisant des colorants fluorescents spécifiques couplés à un réactif, e.g. l’hydrazide qui réagit avec les carbonyles des protéines. Cependant, les colorants souffrent de faible biocompatibilité, faible solubilité et d'une photostabilité modérée. Pour améliorer la spécificité et la sensibilité nécessaires aux dommages oxydatifs, des stratégies avancées sont nécessaires. Les nanoclusters d'or (AuNC), composés de plusieurs centaines d'atomes d'or et protégés par des ligands thiolés, présentent des effets de confinement quantique et des propriétés de type moléculaire avec propriétés de photoluminescence uniques. De plus, les propriétés optiques non linéaire impressionnante de ces nanoclusters en font des candidats prometteurs pour diverses techniques de bio-imagerie telles que la microscopie confocale multiphotonique. L'objectif principal de ce travail de doctorat était de détecter la carbonylation des protéines par des méthodes optiques en utilisant des nanoclusters d'or fonctionnalisés, en allant de gels 2D jusqu’à une exploration in vitro. Ce manuscrit est organisé en quatre chapitres. Dans le premier chapitre, je passerai brièvement en revue les stratégies actuelles utilisées pour analyser la carbonylation dans le vivant et le potentiel de l'utilisation de nanoclusters obtenus à la précision atomique pour la détection des groupes carbonyles sur les protéines par des méthodes optiques. Dans le chapitre expérimental, je décrirai les techniques incontournables pour caractériser les nanoclusters et aborder la précision atomique par spectrométrie de masse, comment mesurer leurs propriétés optiques (linéaires et non linéaires), et d'autres méthodes de caractérisation en particulier les techniques de mesure de taille, les microscopies utilisées pour visualiser le signal des gels et les NCs à l'intérieur des cellules, les protocoles chimiques et biologiques de carbonylation. Le troisième chapitre est consacré à la description des nombreuses approches de synthèse (dont la plupart ont été infructueuses) qui nous ont conduits à développer des nanoclusters d'or fonctionnalisés comme sondes luminescentes pour la détection de la carbonylation des protéines. Ce travail a été réalisé en utilisant la protéine modèle lysozyme. En particulier, je décrirai le développement de NCs d'or protégés par des molécules de glutathion et leur fonctionnalisation comme cibles efficaces de la carbonylation, la modification de la composition des gels pour étudier à la fois les protéines et les nanoclusters, les approches protéomiques pour comprendre la quantité et les sites de carbonylation du lysozyme, et la preuve de principe de l'utilisation des NCs comme sondes luminescentes pour la détection de la carbonylation des protéines avec les gels. Dans le dernier chapitre, je décrirai les stratégies que nous avons menées pour rendre les nanoclusters intéressants pour la bioimagerie cellulaire. Et pour la première fois, des mesures de bioimagerie par microscopie confocale multiphotonique ont été démontrées à Lyon en utilisant des NCs à base d'argent internalisées à l'intérieur des cellules. Je terminerai en résumant l'état d'avancement de ce projet, les limitations actuelles ainsi que quelques perspectives pour rendre les nanoclusters réellement utilisables pour les biologistes en particulier dans le contexte du vieillissement cellulaire.

Ovaj diplomski rad svojevrsni je nastavak završnog rada pod nazivom „Priprava i karakterizacija nanočestica CuO sintetiziranih u milireaktoru” u kojem je ispitan postupak dobivanja nanočestica bakrovog (II) oksida korištenjem milireaktora. Prednosti postupka sinteze u odnosu na klasične šaržne su brže dobivanje produkta pri sobnim uvjetima, bez ekstremnih tlakova i temperatura te kontinuirani način proizvodnje. U eksperimentalnom dijelu rada provedene su daljnje analize te su ispitana optička svojstva nanočestica. Nanočestice su karakterizirane kvalitativno UV/VIS metodom i FTIR-om. UV/VIS spektar dobivenih nanočestica pokazuje maksimume apsorpcija ispod 300 nm što karakterizira plavi pomak uslijed učinka kvantnog zatočenja, dok su na prikazanim FTIR spektrima vidljivi maksimumi frekvencija oko 600 cm^-1 koji odgovaraju vibracijama istezanja Cu-O veze. Pri kratkim vremenima zadržavanja u milireaktoru (τ < 6 minuta) i tretiranjem uzorka mikrovalnim zračenjem različitog intenziteta, dobivene nanočestice su pokazale ravnomjernu raspodjelu veličina čestica koja po literaturi odgovara nanočesticama veličine 2,5 nm. Mjeren je pH otopina i doveden je u korelaciju sa stvaranjem koloida bakrovih oksida. Kod izmjerenog pH < 5,66 ne dolazi do promjene boje uzorka neovisno o snazi mikrovalnog zračenja. This diploma thesis is a continuation of the final paper entitled „Preparation and characterization of CuO nanoparticles synthesized in a milireactor” in which the process of obtaining copper (II) oxide nanoparticles using milireactor was examined. The advantages of the synthesis process compared to conventional batches are faster product production at room conditions, without extreme pressures and temperatures, and a continuous production method. In the experimental part of this paper, further analyzes were performed and the optical properties of nanoparticles were examined. Nanoparticles were characterized qualitatively by the UV/VIS method and FTIR. The UV/VIS spectrum of the obtained nanoparticles shows absorption maximum below 300 nm, which is characterized by a blue shift due to the quantum confinement effect, while the FTIR spectra show high frequencies around 600 cm^-1 corresponding to vibrations of Cu-O bond. With short retention times in the millireactor (τ

Razvijanje čišćih, bržih i ekonomski isplativijih preparativnih metoda jedan je od ciljeva zelene kemije. Izvedivost ovog koncepta zelene kemije demonstrirana je na sintezi organopaladijevih spojeva (paladocikla), zbog njihove važnosti u organskoj sintezi i jedinstvenih optičkih svojstava. Većina sintetskih koraka u ovom radu provedena je reakcijama u čvrstom stanju primjenom metoda mehanokemije ili starenja. Paladocikli s jednom ili dvije veze metal–ugljik i metal–donor dobiveni su aktivacijom veze(a) C–H u azobenzenima različitim katalizatorima paladija(II), a izmjena njihovih anionskih ili neutralnih liganada rezultirala je derivatima s drugačijom reaktivnošću i optičkim svojstvima. Opisane reakcije praćene su spektroskopskim metodama in situ i ex situ što je omogućilo karakterizaciju vrsta uključenih u reakcije, izravan uvid u dinamiku i reakcijske putove, te faktore koji kontroliraju reaktivnost i selektivnost, kao i optimizaciju procesa mljevenja. Primjena razvijenih metoda i koncepata omogućit će sintezu novih organopaladijevih spojeva na ekološki prihvatljiv način, izravnu i selektivnu zamjenu veze C–H drugim funkcionalnim skupinama, te razvoj novih katalizatora. The development of clean, fast, and cost-effective preparative methods is one of the objectives of green chemistry. The feasibility of the green chemistry concept is demonstrated on the synthesis of organopalladium compounds (palladacycles), important due to their wide application in organic synthesis and unique optical properties. The majority of synthetic steps in this thesis were performed by solid-state synthetic method, mechanochemistry and aging. Palladacycles with one or two metal-carbon and metal-donor bonds were prepared via C–H bond(s) activation in azobenzenes by various Pd(II) catalysts, and the exchange of their anionic or neutral ligands resulted in derivatives with different reactivity and optical properties. The described reactions were monitored in situ and ex situ by spectroscopic methods, which enabled the characterization of the species involved in the reactions, direct insight into the reaction pathways, insight into the factors controlling reactivity and selectivity, and optimization of the grinding process. The application of the developed methods and concepts will enable synthesis of new organopalladium compounds, direct and selective replacement of the C–H bond by other functional groups, and the development of new catalysts.

Polivinilpriolidon (PVP) je polimer koji od otkrića (Reppe, 1939.) pa sve do danas privlači veliku pažnju zbog svojih iznimnih svojstava. Posjeduje jedinstvenu kombinaciju fizikalnih i kemijskih svojstava kao što su biokompaktibilnost, netoksičnost, kemijska stabilnost, dobra topljivost u vodi i mnogim drugim organskim otapalima, afinitet prema kompleksnim hidrofilnim i hidrofobnim tvarima. Odličan je za stvaranje filma koji je čvrst, transparentan i sjajan, a zbog netoksičnosti i dobre biološke kompatibilnosti koristi se između ostalog kao vezivo za tablete u farmaceutskim aplikacijama. Uslijed istraživanja dobrih svojstava pokazalo se kako PVP bazirani biomaterijali imaju određene nedostatke te se stoga PVP matrici dodaju razna punila. U ovom radu istražen je utjecaj punila, željezovog (III) oksida (Fe2O3) i željeza (Fe), na svojstva PVP polimera. PVP/Fe2O3 i PVP/Fe kompoziti pripravljeni su zamiješavanjem PVP-a s različitim udjelom punila, φ = 0,1; 0,3; 0,5; i 1,0 % u vodenoj otopini. Mjerenjem kontaktnog kuta određena je slobodna površinska energija komponenata te su izračunati parametri adhezije. Uvid u strukturu PVP polimera i kompozita ispitan je optičkom mikroskopijom dok su toplinska svojstva ispitana diferencijalnom pretražnom kalorimetrijom (DSC), mjerenjem toplinske vodljivosti i termogravimetrijskom analizom (TGA). Rezultati su pokazali kako su oba punila dodana u premalim koncentracijama da bi došlo do nekih značajnijih promjena svojstava PVP polimerne matrice, a prema proračunatim parametrima adhezije zaključeno je kako se značajnije interakcije mogu očekivati u kompozitnom sustavu PVP/Fe2O3. Polyvinylpriolidone (PVP) is a polymer which has attracted a great deal of attention since its discovery (Reppe, 1939) until today due to its exceptional properties. It has a unique combination of physical and chemical properties such as biocompatibility, non-toxicity, chemical stability, good solubility in water and many other organic solvents, affinity to complex hydrophilic and hydrophobic substances. It is excellent for creating solid, transparent and glossy film, and due to its non-toxicity and good biocompatibility, it is used, among other things, as a binder for tablets in pharmaceutical applications. By exploring its good properties, it has been shown that PVP based biomaterials have certain disadvantages and therefore various fillers are addedd to the PVP matrix to improve it's properties. In this paper, the influence of iron (III) oxide (Fe2O3) and iron (Fe) filler addition, on the properties of PVP polymer, was investigated. PVP/Fe2O3 and PVP/Fe composites were prepared by mixing PVP with different filler content, φ = 0,1; 0,3; 0,5 and 1,0 %, in aqueous solution. By measuring the contact angle, the surface energy free of the components was determined and the adhesion parameters were calculated. Structure of PVP polymer and composites was determined by optical microscopy and thermal properties of the samples were investigated by differential scanning calorimetry (DSC), thermal conductivity measurement and thermogravimetric analysis (TGA). The results showed that both fillers were added at too low concentrations to cause some significant changes in the properties of the PVP polymer matrix. According to the calculated adhesion parameters it was concluded that stronger interactions can be expected in composite system PVP/Fe2O3.

High esthetic requirements present a challenge in restorative dentistry due to the complex structure of dental tissues, micromorphology and composition of dentin and enamel. Dental composite material is characterized by its excellent esthetic properties despite significant structural differences from the dental tissues. Nevertheless, optimum esthetic results are not easy to achieve and require balancing several clinical factors. The aim of this dissertation was to evaluate the effect of dentin restoratives with different optical properties than composite materials on the optical characteristics of the final restorations. This doctoral thesis investigates the optical characteristics (color and translucency) of such combined "sandwich" restorations related to their type, shade and thickness of the final composite layer. Fluorescence properties of materials, initial color and color stability and marginal integrity of combined restorations in prepared cavities in extracted teeth are also investigated in relation to the type of dentin restorative and final 'enamel' layer. Materials and Methods: The following materials were used as dentin restoratives: tricalcium-silicate cements (Biodentine, Septodont), experimental hydroxyapatite inserts (HAP), fiber-reinforced composite (EverX Posterior, GC). Filtek Z250 (micro-hybrid with Bis-GMA, 3M ESPE), Filtek Z550 (nano-hybrid, 3M ESPE), Gradia Direct (micro-hybrid without Bis-GMA, GC), of A1 or A3 shade, were used as control groups. For bulk-fill restorations nano-hybrid bulk-fill composite materials were used: Filtek Bulk Fill Posterior (3M ESPE) and Tetric EvoCeram Bulk Fill (Ivoclar Vivadent). Adhesives: Single Bond Universal (3M ESPE), Adhese Universal (Ivoclar Vivadent), GC G-aenial Bond (GC) were used with the respective composites. In the first part of the study, optical parameters of all materials, prepared in different layer thickness and shades were measured. Samples were made in standardized cylindrical plastic molds. Color (ΔE) and translucency (TP) were measured using a spectrophotometer VITA Easyshade® Advance 4.0 (VITA Zahnfabrik). The color, expressed as the deviation from ‘ideal white’, and translucency were determined according tothe CIEL*a*b* color system..., Estetski zahtevi predstavljaju izazov u restaurativnoj stomatologiji, pre svega zbog kompleksne strukture dentalnog tkiva, mikromorfologije i sastava dentina i gleđi. Dentalni kompozitni materijali odlikuju se izvanrednim estetskim svojstvima, iako se strukturalno znatno razlikuju od zubnih tkiva. Međutim, postizanje optimalnih estetskih rezultata nije uvek jednostavno i zahteva balans više kliničkih faktora. Predmet ove doktorske disertacije je ispitivanje uticaja dentinskih zamenika, bitno različitih estetskih svojstava od kompozitnih materijala, na optičke karakteristike finalne restauracije. Ispitivani su optički parametri (boja i translucencija) takvih "sendvič" restauracija, uzimajući u obzir vrstu dentinskih zamenika, vrstu, nijansu i debljinu završnog kompozitnog sloja, fluorescencija materijala, zatim inicijalna boja, stabilnost boje i marginalna mikropropustljivost ispuna u preparisanim kavitetima zuba u zavisnosti od materijala za nadoknadu dentina i završni gleđni sloj. Materijali i metode: Materijali koji su korišćeni kao dentinski zamenici su: trikacijum-silikatni cement (Biodentin, Septodont), inserti eksperimentalnog sintetičkog hidroksiapatita (HAP), kompozitni materijal ojačan staklenim vlaknima (everXPosterior, GC). Kontrolnu grupu su predstavljali univerzalni kompozitni materijali: Filtek Z250 (mikro-hibrid sa Bis-GMA-om, 3M ESPE), Filtek Z550 (nano-hibrid, 3M ESPE), Gradia Direct Posterior (mikro-hibrid bez Bis-GMA-e, GC) u dve različite nijanse A1 i A3. Kod restauracije "bulk-fill" tehnikom korišćeni su nano-hibridni bulk fill kompozitni materijali: Filtek Bulk Fill Posterior (3M ESPE) i TetricEvoCeram Bulk Fill (IvoclarVivadent). U ovom istraživanju korišćeni su adhezivi: Single Bond Universal (3M ESPE), Adhese Universal (Ivoclar Vivadent), GC G-aenial Bond (GC). U prvom delu istraživanja izmereni su optički parametri svih materijala, različitih debljina i nijansi. Uzorci su pravljeni u standardizovanim plastičnim kalupima cilindričnog oblika. Merenje je vršeno spektrofotometrom VITA Easyshade Advance 4.0 (VITA Zahnfabrik). Boja (ΔE, odstupanje od idealno bele) i translucencija (TP) su izračunate prema CIEL*a*b* sistemu...

A nonmetal-doped titania has attracted considerable attention in recent years due to its photocatalytic activity in the visible part of the solar spectrum, which is beneficial with regards to pure TiO2. Among the explored nonmetal dopants, nitrogen and sulfur have been shown to be the most promising for the enhancement of photocatalytic activity of TiO2 under visible light. These nonmetals can be introduced to the TiO2 lattice by employing various precursors and preparation methods... Dopiranjem titan(IV)-oksida nemetalima omogućuje se fotokatalitiĉka aktivnost pod dejstvom vidljive svetlosti, što predstavlja veliku prednost dopiranog u odnosu na ĉist TiO2. Najznaĉajniji nemetalni dopanti su azot i sumpor, koji se mogu inkorporirati u strukturu TiO2 primenom razliĉitih prekursora i postupaka sinteze...

Svrha: Dobivanje novih spoznaja o postojanosti optičkih svojstava; boji, svjetlini, kromatičnosti i translucenciji staklo-keramičkih materijala u korozivnom mediju. Materijali i metode: Izrađeno je po tri uzorka (pločice 10 mm × 12 mm × 0,8 mm) IPS e.max keramike (Ivoclar Vivadent, Schaan, Lichtenstein) u tri boje (A2, C2 i B3) trima različitim tehnologijama izrade (slojevanje – IPS e.max Ceram Dentin; toplo-tlačna tehnika – IPS e.max Press; strojno – IPS e.max CAD). Izrađena su i 3 akrilatna uzorka (PMMA) istih dimenzija (Ivoclar Vivadent, Schaan, Lichtenstein) u 3 boje (130, 410, 310). Usporedba je rađena sa standardom, ključem boja Vitapan Classical (Vita Zahnfabrik, Bad Säckingen, Njemačka). Pomoću spektrofotometra (X-Rite DTP 20 Pulse, Neu Isenburg, Njemačka) izmjerene su CIE L*a*b* vrijednosti za izračun razlike u boji (ΔE*), kromatičnosti (ΔC*) parametra tanslucencije (TP vrijednost), prije i poslije izlaganja 4% octenoj kiselini na 80 °C tijekom 16 sati (ISO 6872). Statistički podatci obrađeni su programom IBM SPSS 22. Rezultati: Optička svojstva koja najviše razlikuju istraživane materijale i boje su odstupanje od kromatičnosti i svjetline od standarda. Prije korozije IPS e.max Ceram Dentin ima veće odstupanje u kromatičnosti od standarda, a IPS e.max Press i CAD manje (p

U disertaciji je sprovedeno teorijsko istraživanje fizičko-hemijskih svojstavaelektronskog podsistema molekula sumanena. Proračuni su sprovedeni u okvirima DFT i TDDFT teorije sa B3LYP funkcionalom i 6-31Gd, 6-31Gdp i 6-31++Gdp bazisom. Za sveproračune u okvirima navedenog nivoa teorije, korišćen je softverski paket Gaussian03.Ispitana su: strukturna i optička (zajedno sa nelinearnim) svojstva sumanena i njegovihderivata dobijenih modifikovanjem sa atomima bora iazota, aromatična i inverziona svojstvasvojstva sumanena i njegovih derivata, adsorpciona svojstva sumanena prema molekulimaH2, CO, CO2i NH3i uticaj spoljašnjeg električnog polja na svojstva sumanena.Prema dobijenim rezultatima, fundamentalna fizičko-hemijska svojstva molekulasumanena mogu se efikasno i fino podešavati supstitucijom i disupstitucijom hetero-atomimabora i azota. Dubina i inverziona barijera sumanena se na ovaj način može menjati u obasmera. Pokazalo se da su ova dva parametra u korelaciji, s obzirom da inverziona barijeraskoro potpuno zavisi od dubine sumanena. Slično je i sa aromatičnim svojstvima prstenova,koja se u zavisnosti od broja uvedenih hetero-atomamenja od aromatične preko nearomatičnedo antiaromatične prirode. Optička svojstva su, pomenutim modifikacijama, takođe značajnopoboljšana: apsorpcioni pikovi kod UV/Vis spektra se pomeraju ka vidljivoj oblasti, dok jehiperpolarizibilnost sumanena i derivata sa jednim atomom bora viša od referentnogmolekula uree, respektivno, 9 i 49 puta.Prema dobijenim rezultatima, adsorpciona svojstva sumanena su veoma kompetitivnasa ostalim organskim molekulima kao što su ugljenične nanotube i fuleren C60, usledpostojanja značajnog dipolnog momenta zbog specifične geometrije. Posebno se ističupozitivna adsorpciona svojstva prema molekulima H2i CO. Dok je prvo pomenuti bitan saenergetskog aspekta, specifičnost drugog molekula se ogleda u činjenici da ne može bitiadsorbovan od strane ugljeničnih nanotuba.Potencijal sumanena, posebno u oblasti organske elektronike, dodatno ističu i rezultatiispitivanja uticaja spoljašnjeg električnog polja. Naime, dobijeni rezultati ukazuju da sespecifična (posebno adsorpciona) svojstva sumanena mogu dodatno poboljšati primenomslabog, i eksperimentalno lako ostvarljivog, električnog polja, jer se intenzivira razdvajanjenaelektrisanja., Theoretical investigation of physicochemical properties of electron subsystem ofsumanene molecule has been conducted in this doctoral work. Calculations are performedwithin DFT and TD-DFT with B3LYP functional and 6-31Gd, 6-31Gdp i 6-31++Gdp basissets. For all calculations, on the mentioned level of theory, Gaussian03software package wasused. Investigation encompassed: structural and optical (including nonlinear) properties ofsumanene and its derivatives obtained by modification with boron and nitrogen atoms,aromatic and bowl to bowl inversion properties of sumanene and its derivatives, adsorptionproperties of sumanene towards H2, CO, CO2i NH3molecules and the influence of externalelectric field to the properties of sumanene.According to obtained results, fundamental physicochemical properties of sumanenemolecule could be efficiently and finely adjusted with the monosubstitution and disubstitutionwith hetero-atoms of boron and nitrogen. Bowl depth and bowl to bowl inversion barriercould be tuned in both directions. It was demonstrated that these two parameters arecorrelated, since bowl to bowl inversion barrier principally depends on the fourth power ofbowl depth. Similar situation is with aromatic nature of sumanene rings, which change,depending on the number of introduced boron and nitrogen atoms, from aromatic throughnon-aromatic towards anti-aromatic nature. Thanks to mentioned modifications, opticalproperties are improved as well: absorption peaks in UV/Vis spectra shift towards visiblearea, while hyperpolarizabilities of sumanene and its derivative containing one boron atomare higher than hyperpolarizability of referent molecule of urea, respectively, 9 and 49 times.Thanks to significant dipole moment due to the specific geometry, nvestigated adsorption properties of sumanene are very competitive to the other organic molecules suchas carbon nanotubes and fullerene C60. Positive adsorption properties of sumanene towards H2and CO molecules are distinguished. While the H2molecule is important from the energeticaspects, specificity of CO molecules is that it can’t be adsorbed by carbon nanotubes.Potential of sumanene, especially in the field of organic electronics, is emphasizedthrough the obtained results related to the investigation of the influence of external electricfield. Obtained results indicate that specific (especially adsorption) properties of sumanenecould be additionally improved by application of weak, and experimentally easily achievable,external electric field, due to the higher charge separation.&nbsp

U disertaciji je sprovedeno teorijsko istraživanje fizičko-hemijskih svojstavaelektronskog podsistema molekula sumanena. Proračuni su sprovedeni u okvirima DFT i TDDFT teorije sa B3LYP funkcionalom i 6-31Gd, 6-31Gdp i 6-31++Gdp bazisom. Za sveproračune u okvirima navedenog nivoa teorije, korišćen je softverski paket Gaussian03.Ispitana su: strukturna i optička (zajedno sa nelinearnim) svojstva sumanena i njegovihderivata dobijenih modifikovanjem sa atomima bora iazota, aromatična i inverziona svojstvasvojstva sumanena i njegovih derivata, adsorpciona svojstva sumanena prema molekulimaH2, CO, CO2i NH3i uticaj spoljašnjeg električnog polja na svojstva sumanena.Prema dobijenim rezultatima, fundamentalna fizičko-hemijska svojstva molekulasumanena mogu se efikasno i fino podešavati supstitucijom i disupstitucijom hetero-atomimabora i azota. Dubina i inverziona barijera sumanena se na ovaj način može menjati u obasmera. Pokazalo se da su ova dva parametra u korelaciji, s obzirom da inverziona barijeraskoro potpuno zavisi od dubine sumanena. Slično je i sa aromatičnim svojstvima prstenova,koja se u zavisnosti od broja uvedenih hetero-atomamenja od aromatične preko nearomatičnedo antiaromatične prirode. Optička svojstva su, pomenutim modifikacijama, takođe značajnopoboljšana: apsorpcioni pikovi kod UV/Vis spektra se pomeraju ka vidljivoj oblasti, dok jehiperpolarizibilnost sumanena i derivata sa jednim atomom bora viša od referentnogmolekula uree, respektivno, 9 i 49 puta.Prema dobijenim rezultatima, adsorpciona svojstva sumanena su veoma kompetitivnasa ostalim organskim molekulima kao što su ugljenične nanotube i fuleren C60, usledpostojanja značajnog dipolnog momenta zbog specifične geometrije. Posebno se ističupozitivna adsorpciona svojstva prema molekulima H2i CO. Dok je prvo pomenuti bitan saenergetskog aspekta, specifičnost drugog molekula se ogleda u činjenici da ne može bitiadsorbovan od strane ugljeničnih nanotuba.Potencijal sumanena, posebno u oblasti organske elektronike, dodatno ističu i rezultatiispitivanja uticaja spoljašnjeg električnog polja. Naime, dobijeni rezultati ukazuju da sespecifična (posebno adsorpciona) svojstva sumanena mogu dodatno poboljšati primenomslabog, i eksperimentalno lako ostvarljivog, električnog polja, jer se intenzivira razdvajanjenaelektrisanja., Theoretical investigation of physicochemical properties of electron subsystem ofsumanene molecule has been conducted in this doctoral work. Calculations are performedwithin DFT and TD-DFT with B3LYP functional and 6-31Gd, 6-31Gdp i 6-31++Gdp basissets. For all calculations, on the mentioned level of theory, Gaussian03software package wasused. Investigation encompassed: structural and optical (including nonlinear) properties ofsumanene and its derivatives obtained by modification with boron and nitrogen atoms,aromatic and bowl to bowl inversion properties of sumanene and its derivatives, adsorptionproperties of sumanene towards H2, CO, CO2i NH3molecules and the influence of externalelectric field to the properties of sumanene.According to obtained results, fundamental physicochemical properties of sumanenemolecule could be efficiently and finely adjusted with the monosubstitution and disubstitutionwith hetero-atoms of boron and nitrogen. Bowl depth and bowl to bowl inversion barriercould be tuned in both directions. It was demonstrated that these two parameters arecorrelated, since bowl to bowl inversion barrier principally depends on the fourth power ofbowl depth. Similar situation is with aromatic nature of sumanene rings, which change,depending on the number of introduced boron and nitrogen atoms, from aromatic throughnon-aromatic towards anti-aromatic nature. Thanks to mentioned modifications, opticalproperties are improved as well: absorption peaks in UV/Vis spectra shift towards visiblearea, while hyperpolarizabilities of sumanene and its derivative containing one boron atomare higher than hyperpolarizability of referent molecule of urea, respectively, 9 and 49 times.Thanks to significant dipole moment due to the specific geometry, nvestigated adsorption properties of sumanene are very competitive to the other organic molecules suchas carbon nanotubes and fullerene C60. Positive adsorption properties of sumanene towards H2and CO molecules are distinguished. While the H2molecule is important from the energeticaspects, specificity of CO molecules is that it can’t be adsorbed by carbon nanotubes.Potential of sumanene, especially in the field of organic electronics, is emphasizedthrough the obtained results related to the investigation of the influence of external electricfield. Obtained results indicate that specific (especially adsorption) properties of sumanenecould be additionally improved by application of weak, and experimentally easily achievable,external electric field, due to the higher charge separation.&nbsp

Poznato je da funkcionalna svojstva cink oksidnih prahova zavise od fizičko-hemijskih karakteristika kao što su optičke karakteristike i specifična površina, a koje su određene strukturnim svojstvima praha u kao što su: fazni sastav, veličina kristalita, stepen kristaliničnosti, uređenje kristalne strukture tj. prisustvo defekata kao i morfologija čestica. Navedene karakteristike mogu se podešavati optimizacijom reakcionih uslova tokom procesa sinteze. Cilj ovog istraživanja bio je, kao prvo, sinteza prahova ZnO različitih fizičko-hemijskih karakteristika putem optimizacije reakcionih uslova različitih metoda procesiranja. Nakon toga, ideja je bila da se ispitaju neka od funkcionalnih svojstava sintetisanih prahova ZnO, konkretno, katalitička i antibakterijska svojstva. Konačno, uspostavljena je korelacija između ispitivanih funkcionalnih svojstava i fizičko-hemijskih karakteristika sintetisanih prahova ZnO. U ovom radu primenjena su tri postupka sinteze: hidrotermalno, ultrazvučno i mikrotalasno procesiranje. U slučaju hidrotermalnog procesiranja, promenom pH vrednosti reakcionog sistema, od slabo bazne (pH 8) do jako bazne (pH 12) sredine, uz prisustvo određene količine površinski aktivne komponente, bilo je moguće značajno modifikovati morfologiju i srednju veličinu čestica sintetisanih prahova ZnO. Sintetisane su čestice od štapićastih mikrometarskih formi, pri pH vrednosti reakcionog sistema 8-10, preko elipsoidnih submikrometarskih oblika pri pH 11, do sferičnih nanometarskih čestica pri pH 12-13. Ispitan je i uticaj energije, koja se tokom ultrazvučnog i mikrotalasnog procesiranja unosi u reakcioni sistem, na morfologiju čestica ZnO; zadržani su identični reakcioni uslovi kao i u slučaju hidrotermalnog procesiranja. Utvrđeno je da energija primenjenog spoljašnjeg polja (ultazvučnog ili mikrotalasnog) u značajnoj meri utiče na morfologiju čestica, uređenost strukure i defekte rešetke u molekulu ZnO, što doprinosi poboljšanju ispitivanih funkcionalnih svojstava materijala. Ispitana su optička svojstva sintetisanih prahova ZnO, tačnije, uspostavljena je korelacija između oblika i srednje veličine čestica sa jedne strane i procenta refleksije i energije procepa sa druge strane. Utvrđeno je da se modifikacijom oblika i dimenzija čestica značajno mogu poboljšati optička svojstva ZnO u vidljivom delu spektra. Primenom postupaka heterogene fotokatalize i sonokatalize za razgradnju organske boje metilensko plavo (MB), ispitana su katalitička svojstva prahova ZnO. S obzirom da su sintetisani prahovi čija je energija procepa u vidljivom delu spektra (Ebg=3,25 eV) bilo je moguće povećati efikasnost razgradnje toksične boje (MB) u prisustvu ZnO prahova dodatnim delovanjem svetlosti (fotokataliza) tokom eksperimenata. Delovanjem ultrazvučnog polja (sonokataliza) tokom procesa razgradnje boje MB u prisustvu praha ZnO uočeno je značajno povećanje efikasnosti. U oba slučaja, foto- i sono-katalize, postignuta je dodatna aktivacija čestica ZnO tj. ubrzano je oslobađanje peroksidnih radikala što je za rezultat imalo i visok procenat efikasnosti razgradnje organske boje u ispitivanim disperzijama. Antibakterijska svojstva sintetisanih prahova cink oksida ispitivana su na dve bakterijske ćelijske vrste, gram pozitivne Staphylococcus aureus i gram negativne Escherichia coli. Utvrđeno je da prah ZnO izgrađen od nanosfernih čestica, relativno velike specifične površine, pokazuje najveći procenat redukcije broja živih ćelija tj. najbolju antibakterijsku aktivnost u slučaju ćelija Escherichia coli, dok je najbolju antibakterijsku aktivnost u slučaju ćelija Staphylococcus aureus pokazao prah ZnO izgrađen od heksagonalnih mikronskih štapićastih formi. Ovi rezultati potvrdili su da osim veličine i morfologije čestica na antibakterijsku aktivnost ispitivanog uzorka utiče niz faktora od kojih se posebno ističe vrsta i svojstva bakterijske linije koja se proučava. It is known that the functional properties of zinc oxide powders depend on their physico-chemical properties, such as optical properties and specific surface area wich are defined with structural characteristics for example: the particle size and morphology, phase composition, crystallite size, crystallinity degree, as well as the crystal structure ordering, i.e. the presence of defects. All of these characteristics can be designed by optimizing the reaction conditions during the synthesis. The primary purpose of this study is to synthesize zinc oxide powders with various physico-chemical properties by optimizing the reaction conditions in different processing methods. Furthermore, the aim was to test some of the functional properties of the synthesized ZnO powders – namely, their catalytic and antibacterial properties. Finally, a correlation between the tested functional properties and physico-chemical characteristics of the synthesized ZnO powders has been established. In this thesis, three methods of synthesis have been applied: hydrothermal, ultrasound and microwave processing. In the case of hydrothermal processing it is possible to significantly alter the morphology and the average particle size of the synthesized ZnO particles by changing the pH value of the reaction system, from a weak base (pH 8) to a very strong base (pH 12), in the presence of an amount of surface-active agents. The synthesized particles ranged from rod-shaped micrometer-sized forms at the pH 8–10 reaction system, over submicron ellipsoidal shapes at pH 11, down to the spherical nano-scaled particles obtained at a pH 12–13. The impact of energy introduced into the reaction system during sonochemical and microwave processing on the morphology of ZnO particles has also been examined under the identical reaction conditions as in hydrothermal processing. It has been found that the energy of the applied external field (ultrasound or microwave) considerably affects the particle morphology, the order of the structure and the lattice defects in the ZnO molecule, which contributes improuvement of the tested functional properties of the material. The optical properties of the synthesized powders have been examined; more precisely, the correlation between the shape and the average particle size as well as the reflection percentage and band gap energy has been established. It has been demonstrated that the modification of the particle shape and dimensions can significantly improve the optical properties of ZnO in the visible spectrum. The catalytic properties of ZnO powders have been investigated by heterogeneous photocatalytic and sonocatalytic degradation of an organic dye, methylene blue (MB). Having in mind that the synthesized powders whose energy gaps are in the visible spectrum (Ebg = 3.25 eV), it is possible to increase the efficiency of the degradation of the toxic dye (MB) in the presence of ZnO powders by an additional exsposure to the light (photocatalysis) during the experiments. When an ultrasonic field (sonocatalysis) is applied during the decomposition process of MB in the presence of a ZnO powder, a significant increase in efficiency is observed. In both cases, photo- and sonocatalysis, an additional activation of ZnO particles, i.e. an accelerated release of peroxide radicals is observed, which results in a high efficiency of the degradation of the organic dye in the tested dispersions. The antibacterial properties of the synthesized ZnO powders were tested on two types of bacterial cells, gram positive – Staphylococcus aureus and gram – negative Escherichia coli. It has been found that the ZnO powder consisting of nanospherical particles with a relatively large specific surface area, shows the greatest percentage of the reduction in the number of viable cells, i.e. the best antibacterial activity in the case of Escherichia coli cells, while the best antibacterial activity in the case of Staphylococcus aureus cells was exhibited by the ZnO powder consisting of hexagonal ZnO micron-sized rod-like forms. These results have confirmed that in addition to particle size and morphology, the antibacterial activity of the examined sample is influenced by a number of factors; particularly important among them are the type and properties of the investigated bacterial lines.

Ova disertacija se bavi proračunom stanja neutralnog ekscitona u poluprovodničkim nanotačakama (kvantnim tačkama) i nanoprstenovima (kvantnim prstenovima) i modelovanjem njihovih optičkih osobina. Neutralni eksciton je kvazičestica koja predstavlja vezano stanje elektrona i šupljine izmeĎu kojih postoji privlačna Coulombova sila. Iako je električno neutralan, polarizacija ekscitona je konačna usled različitog konfiniranja elektrona i šupljine u nanotačkama. Ovo dovodi do povoljnih uslova za manifestaciju efekata kvantne interferencije, kakav je ekscitonski Aharonov-Bohmov (AB) efekat. Ovaj istaknuti efekat, koji otvara mogućnosti primene nanotačaka i nanoprstenova u nanoelektronici i fotonici, uslovljen je sastavom i morfologijom nanostrukture koji suštinski zavise od tehnologije koja se koristi za izradu nanotačaka i nanoprstenova. Stoga je u disertaciji dat sistematizovan prikaz novijih tehnika za formiranje nanotačaka i nanoprstenova. Prva prikazana tehnika je modifikovana kapljična epitaksija, koja se koristi za proizvodnju nenapregnutih GaAs/(Al,Ga)As nanotačaka, čiji se oblik moţe kontrolisati izborom odreĎenih tehnoloških parametara. Druga tehnika je Stranski-Krastanow (SK) mod narastanja, koji se koristi za proizvodnju napregnutih nanotačaka, kao što su one od (In,Ga)As u matrici od GaAs. Dimenzije ovih nanotačaka su reda nanometra, i paţljivom kontrolom parametara rasta ove nanotačke se mogu pretvoriti u strukture slične prstenovima, koje se nazivaju nanoprstenovi. MeĎutim, po rastu nanoprstena zaostaje tanak sloj unutar njegovog nominalnog otvora, tako da topologija ove strukture nije dvostruko povezana. Dat je sumarni pregled III-V poluprovodničkih jedinjenja i njihovih legura koje se koriste za proizvodnju analiziranih nanotačaka i nanoprstenova. Prikazane su i diskutovane formule koje se koriste za računanje parametara zonske strukture za datu temperaturu, molski udeo itd. Detaljno su opisani teorijski modeli analiziranih nanostruktura. Razmatrane su osobenosti aksijalno simetričnih nanotačaka i nanoprstenova. Korišćena su dva modela naprezanja koji su zasnovani na mehanici kontinuuma: kontinualno mehanički-model iv (CM) za slučaj kada je anizotropija elastičnih osobina prisutna u strukturi i jednostavni model izotropne elastičnosti (IE). Pokazano je da se rezultati dva modela malo meĎusobno razlikuju za analizirane aksijalno simetrične strukture. U slučaju idealizovane geometrije sa strmim granicama na mestu heterospoja postojeći IE model je sveden na numeričko rešavanje jednodimenzionih (1D) integrala... The main objective of the presented thesis is the calculation of the neutral exciton states in semiconductor nanodots (quantum dots) and nanorings (quantum rings) and the modelling of their optical properties. The neutral exciton is a quasiparticle that represents a bound state of the electron and hole which mutually interact by the attractive Coulomb force. Although the exciton is an electrically neutral object, the different confinement of the electron and hole in the nanodot brings about a finite exciton polarization. This in turn establishes a favorable condition for the manifestation of quantum interference effects, such as the excitonic Aharonov-Bohm (AB) effect. This quantum effect, which opens up venues for practical applications of nanorings and nanodots in nanoelectronics and photonics, is influenced by the composition and the morphology of the specific nanostructure, which essentially depends on the technology employed for the fabrication of those nanodots and nanorings. Therefore, recent techniques for the fabrication of nanodots and nanorings are systematically reviewed in the thesis. The first is the modified droplet epitaxy, which allows the fabrication of unstrained GaAs/(Al,Ga)As nanodots, whose shape could be easily controlled by varying certain technological parameters. The second technique is the Stranski-Krastanow (SK) mode of epitaxial growth, which is employed to produce strained nanodots, such as those made of (In,Ga)As in a matrix of GaAs. Their dimensions are of the order of a few nanometers, and by careful control of the growth parameters these nanodots can be turned into ring-like structures, which are called nanorings. However, after growth a thin layer remains inside the nominal ring opening, therefore they do not have double connected topology. The properties of III-V semiconductor compounds and their alloys which are employed to fabricate the analyzed nanodots and nanorings are reviewed. The formulas for computing various band structure parameters for a given temperature, mole fraction etc. are given and discussed. The theoretical models of the analyzed nanodots are described in detail. Peculiarities of the axially symmetric nanodots and nanorings are considered. I used two vii models of elasticity which are based on continuum mechanics: the continuummechanical model (CM) was applied to the case when anisotropic elasticity is present in the structure, and a simple model of isotropic elasticity (IE). I showed that the results of those two models negligibly deviate from each other for the analyzed axially symmetric structures. Furthermore, in the case of an idealized geometry with steep boundaries at the heterojunction the results of the IE model could be reduced to one-dimensional (1D) integrals that have to be calculated numerically...

During two cruises of the MEDUZA experiment conducted in July 2003 and May 2005 various data were obtained over the deepest part of the southern Adriatic Pit. Temperature, salinity, light transmission and fluorescence were measured in July 2003. During May 2005, except CTD measurements the samples were taken for laboratory determination of phytoplankton pigments with HPLC technique. During both cruises irradiance and radiance were measured at 14 wavelengths in the range 340-715 nm with optical probe to about 100 m depth. Bad weather conditions during both cruises caused interruption of measurements that continued after 24 to 48 hours. Stormy conditions have resulted in a slightly different structure of the water column. In the periods of measurements recorded were diurnal rhythms in a series of parameters, caused by solar radiation cycles in the surface layers as well as fluctuations in the deeper layers under the influence of the internal tide. Meteorological conditions and changes in sea level are also described. The analysis included the principal component and correlation analysis between the measured and derived parameters in order to establish a link between the in-situ pigments and multispectral data. During both cruises diurnal vertical oscillations were observed in biotic and abiotic parameters. Chlorophyll pigments prevailed over other pigments preventing other pigments to be distinguished spectrally. Regression models for chlorophyll a were established from radiance and reflectance ratios., Tijekom nekoliko krstarenja u okviru Meduza eksperimenta obavljenih u srpnju 2003 i svibnju 2005 (http://jadran.izor.hr/meduza/meduza_g.htm), pribavljeni su raznovrsni podaci iznad najdubljeg dijela južnog Jadrana. Temperatura, salinitet, propusnost za svjetlost i fluorescencija mjereni su u srpnju 2003. Tijekom svibnja 2005., osim CTD mjerenja uzeti su uzorci za laboratorijsko određivanje pigmenata fitoplanktona. Tijekom oba krstarenja mjereno je zračenje na 14 valnih duljina u rasponu 340-715nm optičkom sondom do oko 100m dubine. Loši vremenski uvjeti tijekom oba krstarenja uzrokovali su prekid mjerenja koja se nastavljaju nakon 24 odnosno 48 sati. Olujni uvjeti rezultirali su nešto drugačijom strukturom vodenog stupca. U razdobljima mjerenja zabilježeni su dnevni ritmovi u nizu parametara, uzrokovani ciklusima sunčeva zračenja u površinskim slojevima kao i oscilacije u dubljim slojevima zbog unutarnje plime. Meteorološki uvjeti i promjene razine mora su također diskutirani. Analiza je obuhvatila i korelacije između izvedenih i mjerenih parametara s ciljem da uspostavi veza između koncentracija mjerenog klorofila i multispektralnih podataka. Tijekom oba krstarenja opažene su dnevne vertikalne oscilacije biotskih i abiotskih pametera. Klorofilni su pigmenti prevladavali onemogućujući spektralno prepoznavanje ostalih pigmenata. Utvrđeni su regresivni modeli za klorofil a na osnovi mjerenja radijanca i reflektancija.

Ultrathin layers of noble metals obtained by deposition to the substrate during evaporation in high vacuum represent nanostructured matter. Nanoparticles showing interesting optical properties due to the localized surface plasmons are formed instead of homogenous layer. Optical properties of noble metal nanoparticles are closely related to their size, shape, distribution and dielectric environment. Localized surface plasmon properties may be tailored by changing deposition parameters (amount of material and substrate temperature) or by changing dielectric environment (dielectric layers below and/or above metal nanoparticles). The goal of research was to correlate optical and structural properties of noble metal island films. Results show that different combinations of ultrathin noble metal layers and dielectric layers have a potential for application in novel optical components. Ultrathin layers of noble metals obtained by deposition to the substrate during evaporation in high vacuum represent nanostructured matter. Nanoparticles showing interesting optical properties due to the localized surface plasmons are formed instead of homogenous layer. Optical properties of noble metal nanoparticles are closely related to their size, shape, distribution and dielectric environment. Localized surface plasmon properties may be tailored by changing deposition parameters (amount of material and substrate temperature) or by changing dielectric environment (dielectric layers below and/or above metal nanoparticles). The goal of research was to correlate optical and structural properties of noble metal island films. Results show that different combinations of ultrathin noble metal layers and dielectric layers have a potential for application in novel optical components.

The invasive algae in the Mediterranean Caulerpa taxifolia and Caulerpa racemosa var. cylind-racea have gained much interest in the Adriatic Sea due to their fast spread and negative impacts on native seaweed species. Lack of accurate mapping and its overall high costs represent some of the major difficulties for successful detection and subsequent environmental management. Remote sensing techniques could provide a quicker, more accurate and more cost efficient approach to mapping these invasive species. In order to allow for classification of remotely sensed data, we have collected and analyzed hyperspectral reflectance profiles of both invasive Caulerpa species in the Adriatic and the native Caulerpa cf. laetevirens species from the southeastern Atlantic coast of the United States. We have measured distinctive spectral features for spectroscopically distinguishing between these species, which is particularly interesting in the areas where these native and invasive species coex-ist. The initial results suggest that it might be possible to distinguish between the species based on their spectral reflectance profile. These results would have to be verified with samples taken from more populations in different phenological phases of the seaweed growth and other environmental conditions., Invazivne alge u Sredozemnom moru, Caulerpa taxifolia i Caulerpa racemosa var. cylindracea, su izazvale mnogo interesa zbog svojeg brzog širenja i negativnih utjecaja na nativne vrste morskog raslinja. Jednu od najvećih poteškoća za upravljanje ovim invazivnim vrstama predstavlja nedostatak preciznih karata rasprostranjenosti, odnosno visoka cijena izrade ovakvih karata. Tehnike daljinske detekcije mogu pružiti brži, učinkovitiji i ekonomičniji način kartiranja ovih vrsta. Kako bi omogućili klasifikaciju podataka prikupljenih daljinskom detekcijom, sakupljeni su i analizirani hiperspektralni profili obje invazivne vrste kaulerpe u Jadranu i nativne vrste Caulerpa cf. laetevirens na jugoistočnoj atlantskoj obali Sjedinjenih Američkih Država. Izmjerena su i utvrđena karakteristična spektralna obilježja ovih vrsta u cilju omogućavanja njihovog spektroskopskog razlikovanja, što je naročito interesantno u onim područjima gdje koegzistiraju nativne i invazivne vrste kaulerpe. Inicijalni rezultati pokazuju da je moguće razlikovati vrste između ovih tipova na osnovu njihovog spektralnog profila. Ovi rezultati još trebaju biti potvrđeni na uzorcima iz više populacija u različitim fenološkim fazama i u različitim uvjetima okoliša.