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U ovom radu je istražen utjecaj molarne mase polielektrolita na formiranje i svojstva polielektrolitnog višesloja poli(alilamin-hidroklorida) i poli(akrilne kiseline). U te svrhe filmovi su pripravljeni s različitim kombinacijama molarnih masa polielektrolita sloj po sloj metodom na površini silicijeva supstrata pri različitim eksperimentalnim uvjetima kako bi se utjecalo na konformaciju polimernih lanaca. Elipsometrom je praćena debljina filma tijekom njegove priprave, a mikroskopom atomskih sila je određena morfologija, hrapavost i poroznost površine filma. Iz dobivenih podataka utvrđeno je da se povećanjem molarne mase polielektrolita povećava debljina filma ako je barem jedan polielektrolit u globularnoj konformaciji. Pokazano je da molarna masa polielektrolita nema značajni utjecaj na debljinu i hrapavost filma ako su oba polielektrolita u izduženoj konformaciji. Otkrivena su i dva nova načina priprave ultra-tankih filmova (d ≈ 2 nm) s poli(akrilnom kiselinom) male molarne mase. In this study the influence of the polyelectrolyte molar mass on the formation and properties of poly(allylamine hydrochloride)/poly(acrylic acid) polyelectrolyte multilayer was investigated. For these purposes, films were prepared on the silicon substrate using layer by layer method with different combinations of polyelectrolyte molar masses under different experimental conditions in order to influence the conformation of the polymer chains. The thickness of the film was monitored during its preparation with an ellipsometer and the morphology, roughness, and porosity of the film surface were determined with an atomic force microscope. From obtained data, it was established that by increasing the polyelectrolyte molar mass, the thickness of the film increases if at least one polyelectrolyte is in globular conformation. On the other hand, if both polyelectrolytes are in an elongated conformation, the polyelectrolyte molar mass has no significant influence on the thickness and roughness of the film. Also, two new ways of preparation of ultra-thin films (d ≈ 2 nm) were discovered by using poly(acrylic acid) of low molar mass.

Polyelectrolyte multilayers are coatings formed by the alternate deposition of polycations and polyanions on a charged surface. In this study we examined how the type of substrate affects a multilayer prepared from poly(allylamine hydrochloride) and poly(acrylic acid). Silicon and titanium wafers were used as substrates. Their properties were systematically studied using ellipsometry, tensiometry, atomic force microscopy and streaming potential measurements. Multilayers were built up at pH = 7 with tetramethylammonium chloride as the background salt. The growth of films was monitored by ellipsometry, while the morphology and surface roughness were determined by atomic force microscopy. It was found that the thickness of multilayers containing 10 layers on silicon is 10 nm, whereas the thickness of the same film on titanium is three times higher. It was shown that multilayers formed on silicon display a grain-like structure, which was not the case for a film formed on titanium. Such morphological properties are also reflected in the surface roughness. Finally, it was shown that, in addition to the electrostatic interactions, the hydrophobicity of the substrate also plays an important role in the polyelectrolyte multilayer formation process and influences its thickness and properties.

Protitelesa so ena izmed glavnih komponent imunskega sistema in čedalje širše uporabljana v terapevtske namene. Zaradi močne odvisnosti oblike teh velikih proteinskih molekul in s tem medmolekulskih sil od lokalnega okolja so protitelesa nagnjena tako k adsorpciji na faznih mejah kot tudi samoagregaciji. V tem magistrskem delu sta bila procesa spremljana na dva načina. S pomočjo mikroskopije pod Brewstrovim kotom (BAM) smo pomerili adsorpcijsko dinamiko proteinskih filmov na fazni meji voda-zrak. Filme dveh protiteles smo kontrolirano prebodli in spremljali odbojnost površine med njihovo rekonstitucijo. Iz meritev smo določili odvisnost hitrosti rekonstitucije filma od koncentracije protiteles pri koncentraciji $mathrm{0.1 mg/mL}$ se npr. film popolnoma rekonstituira v času reda $mathrm{10 s}$. Pri natančnosti izvedenih meritev ni bilo opaženih sistematskih razlik med opazovanima tipoma proteina. Proces smo modelirali s preprostim 2D modelom po metodi končnih elementov in izboljšanim 3D modelom prekurzorsko mediirane adsorpcije. Dodatno smo proteinske filme kontrolirano motili in agregirane proteinske delce analizirali z optično mikroskopijo. V mehansko motenih vzorcih smo periodično zajemali slike dna posod z raztopinami in razvili skripto za njihovo avtomatsko analizo. Za obe opazovalni metodi smo preverili tudi odvisnost rekonstitucije oz. agregacije od koncentracije surfaktantskih molekul. Mejni koncentraciji za tvorbo proteinskega filma in agregacijo sta bili znatno nižji od kritične micelarne koncentracije surfaktantov. Antibodies are a crucial part of the immune system and increasingly used for therapeutic purposes. Due to the strong dependance of conformations of these large protein molecules and ensuing intermolecular forces on local conditions, antibodies are prone to both adsorption at interfaces and formation of aggregates. In this master's thesis, the processes were monitored in two ways. We measured the adsorption dynamics of protein films at the water-air phase boundary using Brewster angle microscopy (BAM) by puncturing films of two antibodies in a controlled manner and monitoring changes in reflectivity during their reconstitution. From the data, we determined the dependance of reconstitution speed on antibody concentrations at a concentration of $mathrm{0.1 mg/mL}$, for example, the film fully reforms in a timespan of $mathrm{10 s}$. At the precision of the measurements carried out, a systematic difference between the observed protein types could not be detected. We modelled the process with a simple 2D model based on the finite element method and an improved 3D model of precursor-mediated adsorption. Additionally, we subjected the protein films to controlled agitation and analysed the aggregated protein particles using optical microscopy. Images of container bottoms of agitated samples were periodically taken and a script was developed for their automatic analysis. For both observation methods, we also examined the effect of surfactant molecules on reconstitution/aggregation. Concentration limits for the formation of a viscoelastic film and aggregation were significantly below the critical micelle concentration of surfactants.

U ovom radu je istražen utjecaj molarne mase polielektrolita na formiranje i svojstva polielektrolitnog višesloja poli(alilamin- hidroklorida) i poli(akrilne kiseline). U te svrhe filmovi su pripravljeni s različitim kombinacijama molarnih masa polielektrolita sloj po sloj metodom na površini silicijeva supstrata pri različitim eksperimentalnim uvjetima kako bi se utjecalo na konformaciju polimernih lanaca. Elipsometrom je praćena debljina filma tijekom njegove priprave, a mikroskopom atomskih sila je određena morfologija, hrapavost i poroznost površine filma. Iz dobivenih podataka utvrđeno je da se povećanjem molarne mase polielektrolita povećava debljina filma ako je barem jedan polielektrolit u globularnoj konformaciji. Pokazano je da molarna masa polielektrolita nema značajni utjecaj na debljinu i hrapavost filma ako su oba polielektrolita u izduženoj konformaciji. Otkrivena su i dva nova načina priprave ultra-tankih filmova (d ≈ 2 nm) s poli(akrilnom kiselinom) male molarne mase.

Naizmjeničnom adsorpcijom pozitivnih i negativnih polielektrolita (tzv. sloj-po-sloj metodom) na nekoj površini nastaju višeslojevi. Svojstva dobivenih filmova ovise o eksperimentalnim parametrima poput korištenih polielektrolita, vrste supstrata, ionske jakosti te vrste pozadinske soli. U ovom diplomskom radu je istraženo kako vrsta dvovalentnog kationa utječe na svojstva višesloja pripravljenog od poli(dialildimetilamonijeva klorida) i poli(natrijeva 4-stirensulfonata). Izabrani kationi su Mg2+, Ca2+, Sr2+, Ba2+, Ni2+, Zn2+ i Cu2+ . Elipsometrijom je praćen rast filmova do deset slojeva, a morfologija i površinska hrapavost određeni su mikroskopom atomskih sila. Tenziometrijom je praćena promjena močivosti površine prilikom adsorpcije svakog polielektrolitnog sloja. Dobiveni rezultati ukazuju da kod kationa zemnoalkalijskih metala postoji ion-specifični efekt koji nije uočen kod kationa prijelaznih metala. Tako su debljine, hrapavosti i močivosti filmova priređenih uz katione prijelaznih metala slične, dok se ova svojstva međusobno razlikuju za višeslojeve priređene uz katione zemnoalkalijskih metala. Polyelectrolyte multilayers are formed by alternating adsorption of polycations and polyanions on a surface (layer-by-layer method). The properties of the film depend on the experimental parameters such as used polyelectrolytes, type of substrate, ionic strength and type of the background salt. In this thesis it was investigated how the type of divalent cation affects the multilayer prepared from poly(diallyldimethylammonium chloride) and poly(sodium 4- styrenesulfonate). Selected cations are Mg2+, Ca2+, Sr2+, Ba2+, Ni2+, Zn2+ and Cu2+ . The growth of films up to ten layers was monitored by ellipsometry, while morphology and surface roughness were determined by atomic force microscopy. The change in surface wettability during adsorption was monitored by tensiometry. Ion-specific effect was observed for alkaline earth metal cations, while in the case of transition metal cations it was not. The thicknesses, roughness and wettability of films prepared with transition metal cations are similar, while these properties differ for multilayers prepared with cations of alkaline earth metals.

Polielektroliti su makromolekule, najčešće polimeri, kod kojih je prisutan znatan udio gradivnih jedinica koje sadrže ionske ili lako ionizirajuće funkcionalne skupine. Primjeri takvih makromolekula su PAH – poli(alilamin hidroklorid) i PAA – poli(akrilna kiselina) čije su kemijske strukture prikazane na slici 1. Naizmjeničnom adsorpcijom pozitivno i negativno nabijenih polielektrolita na neku čvrstu površinu nastaju polielektrolitni višeslojevi. Ovakvom sloj-po-sloj metodom [1] se mogu veoma precizno dizajnirati nanofilmovi željenih svojstva. Upravo se zbog tog razloga ovi nanomaterijali sve intenzivnije istražuju kako bi se mogli primijeniti primjerice kod antibakterijske zaštite implantanta [2]. Najčešće korišteni modelni supstrat za formiranje polielektrolitnih filmova je pločica silicija na čijoj površini spontano nastaje tanki oksidni sloj [3]. Stoga se u prvoj fazi ove studije provela karakterizacija podloge od silicija, kako bi se u drugoj fazi pratilo i istražilo formiranje PAH/PAA polielektrolitnog višesloja na navedenom supstratu. Od brojnih metoda koje su korištene, ovdje će biti izdvojene samo elipsometrija i mikroskopija atomskih sila. Primjenom elipsometra određeno je da se na površini silicija nalazi oko 2 nm debeli sloj oksida. Potom je istom metodom praćena debljina PAH/PAA višesloja tijekom njegovog formiranja. I na kraju, snimanjem površine čistog supstrata i supstrata prekrivenog filmom mikroskopom atomskih sila dobile su se informacije o morfologiji i hrapavosti površine uzoraka, o prekrivenosti površine supstrata polielektrolitnim višeslojem i o debljini samog ultratankog filma.

U ovom radu istražen je utjecaj strukture adsorbata, vremena na koje je supstrat uronjen u otopinu adsorbata te koncentracije otopine na stvaranje samoudruženih monomolekulskih i bimolekulskih slojeva derivata nitrozobenzena na površini zlata (111). U tu svrhu pripravljena su tri derivata nitrozobenzena koji su u para-položaju obzirom na nitrozo skupinu supstituirani alkilnim lancima različitih duljina na čijim se krajevima nalaze tiocijanatne skupine. Samoudruženi molekulski slojevi priređeni su adsorpcijom derivata nitrozobenzena na površinu zlata (111) preko atoma sumpora. Prosječne debljine molekulskih slojeva derivata nitrozobenzena na zlatu te njihova ovisnost o strukturi adsorbata i eksperimentalnim uvjetima priprave slojeva istražene su pomoću elipsometrije. Rezultati ovog rada ukazuju da sposobnost formiranja samoudruženih bimolekulskih slojeva derivata nitrozobenzena s kraćim alkilnim lancima raste s vremenom na koje je supstrat zlata uronjen u otopinu spoja te s povećanjem koncentracije otopine. The influence of the adsorbate structure, the adsorption time and the concentration of the solution on the formation of self-assembled mono- and bilayers of nitrosobenzene derivatives on gold (111) surface was investigated. For that purpose, three nitrosobenzene derivatives substituted with thiocyanate-ended alkyl chains of different lengths in a para-position relative to the nitroso group were synthesized. Self-assembled layers were prepared by adsorption of nitrosobenzene derivatives on the gold surface through the sulphur atom. The average thicknesses of the molecular layers of nitrosobenzene derivatives and their dependence on the adsorbate structure and experimental conditions of layer preparation were studied by ellipsometry. The results of this work indicate that the ability of nitrosobenzene derivatives with shorter alkyl chains to form self-assembled bilayers increases with the adsorption time and with the increase of the concentration of the solution.

Sa najnovijim razvojem nanotehnologije došlo je do ponovnog interesovanja za polje plazmonike. Nanoplazmonika povezuje fotoniku sa nanonaukama tako što konfinira svetlost u nanometarske zapremine, dok se manipulacija svetlošću na nanoskali bazira na osobinama prostirućih i lokalizovanih površinskih plazmona. Važan korak u eksploataciji plazmonskih nanostruktura je njihov dizajn i karakterizacija. Najčešće korišćene tehnike za karakterizaciju se baziraju na merenjima intenziteta. One daju informacije o amplitudama reflektovanih ili transmitovanih talasa nakon njihove interakcije sa uzorkom, ali ne daju nikakvu informaciju o njihovim fazama. U ovom radu, formira se strategija za karakterizaciju plazmonskih nanostruktura korišćenjem spektroskopske elipsometrije (SE), koja sama po sebi meri odnos amplituda i razliku faza za dve karakteristične polarizacije. SE je veoma brza, nedestruktivna, neninvazivna, apsolutna i veoma precizna tehnika, ali zahteva složeno modelovanje za interpretaciju eksperimentalnih rezultata. U tu svrhu, korišćena su dva programska paketa COMSOL Multiphysics i RET)COLO-2D. Odgovarajuće simulacije omogućuju izdvajanje informacija koje nisu dostupne u samom eksperimentu. Proučavani su i prostirući i lokalizovani površinski plazmoni, prvi pobuđeni u fišnet nanostrukturama i drugi koji se javljaju u SRR (engl. Split Ring Resonators). )zučavane fišnet strukture, bazirane su na dvo-dimenzionom (2D) nizu pravougaonih rupa izbušenih u zlato/silicijum dioksid/zlato tankim slojevima. Ove strukture podržavaju jako konfinirane GPP (engl. Gap Plasmon Polariton) u tankom dielektričnom sloju. Kada su rupe ozbušene u 2D periodičnu mrežu veličine 500 x 600 nm2, moguće je direktno optičko pobuđivanje GPP u bliskom infracrvenom delu spektra. Analizom elipsometrijskih spektara, otkriveno je da su GPP efikasnije pobuđeni i disperzija im manje odstupa od disperzije GPP u glatkoj strukturi kada je upadna svetlost polarizovana duž kraćih ivica rupa. Mogući razlog za ovakvo ponašanje je ekscitacija lokalizovanih rezonanci rupa na učestanostima bliskim GPP. )pak, simulacije u kojima su posmatrane manje rupe, pri čemu je zadržan odnos širina/dužina kao kod originalnih fišnet struktura, pokazuju da zavisnost od polarizacije postoji čak i kada se rezonanca rupe me poklapa sa GPP rezonancama. Ovaj efekat je objašnjen pomoću kvazi-statičke polarizabilnosti rupa. Optičko pobuđivanje lokalizovanih plazmonskih rezonanci u 2D poređanim SRR posmatrano je u srednjem infracrvenom delu spektra. Elipsometrijski spektri su objašnjeni na osnovu izračunatih kompleksnih koeficijenata refleksije za dve karakteristične polarizacije. Pokazano je da izbor upadne ravni dosta utiče na formiranje SE spektara. Ako se upadna ravan poklapa sa ravni simetrije, vrhovi u SE spektrima odgovaraju parnim plazmonskim modovima, a kada je upadna ravan ortogonalna na ravan simetrije, vrhovi potiču od pobuđivanja neparnih modova. Kako su elipsometrijska merenja vršena pri kosim upadnim uglovima, javlja se retardacija upadnog polja. To omogućava ekscitaciju modova koji nisu dozvoljeni simetrijom SRR pri normalnoj incidenciji. Veliko pojačanje polja na rezonancijama daje površinski pojačanu infracrvenu SE, dok strmi skokovi u spektrima faze na rezonantnim učestanostima povećavaju osetljivost elipsometrijskog odziva na različite faktore iz sredine u kojoj se nalaze SRR. Recent developments of nanotechnology renewed interests in the field of plasmonics. Nanoplasmonics connects photonics to nanosciences by squeezing the light into nanometer sized volumes, while the light manipulation at the nanoscale is based on properties of propagating and localized surface plasmons. Important step in exploitation of plasmonic nanostructures is their design and characterization. Most frequently used techniques for characterization are based on intensity measurements. They give information about the amplitudes of reflected or transmitted waves after their interaction with the sample, but they do not give any information about their phases. In this work, we are creating strategy how to characterize plasmonic nanostructures using spectroscopic ellipsometry (SE), which inherently measures amplitude ratio and phase difference for the two characteristic polarizations. SE is very fast, nondestructive, noninvasive, absolute and very precise technique, but it requires advanced modelling to interpret experimental data. For that purpose, we are using two numerical packages COMSOL Multiphysics and RETICOLO-2D. Correct simulations enable extraction of additional information, non-accessible through the experiment. Both propagating and localized surface plasmons are studied, first excited in fishnet nanostrucutres and later appearing in split ring resonators (SRR). Fishnet structures considered here, are based on two-dimensional array of rectangular holes perforated in gold/silica/gold thin film stack. These structures support highly confined gap plasmon polartions (GPPs) in the thin dielectric layer. The 500 x 600 nm2 periodic arrangement of the holes enables direct optical excitation of GPPs at near-infrared frequencies. Analyzing the features in the ellipsometric spectra, it is found that the GPPs are much more efficiently excited and have a higher deviation from the flat film GPP dispersion when incident light is polarized along the short axis of the holes. Potential reason for this behavior is excitation of localized resonances of the holes at frequencies close to those of GPPs. However, simulations that included smaller holes with the same aspect ratio as the original ones, suggest that polarization dependence persists even in the absence of the hole resonances. This effect is explained by quasi-static polarizability of the holes. Optical excitation of localized plasmon resonances in 2D array of split ring resonators (SRR) is investigated in the mid-infrared range. The features in the ellipsometric spectra are explained on the basis of calculated polarized complex reflection spectra. It is shown that the choice of plane of incidence (POI) greatly affects the SE spectra. If POI matches mirror symmetry plane of the SRRs, peaks in the ellipsometric spectra correspond to even plamonic modes and if POI it is orthogonal to the symmetry plane, then peaks originate from odd modes excitation. Oblique incidence ellipsometric measurements lead to retardation of the incident field. This provides excitation of modes prohibited at normal incidence by symmetry of SRRs. We also suggest that the great field enhancement at the resonant frequencies enables surface enhanced infrared spectroscopic ellipsometry, while the steep slopes in phase spectra at the resonances improve sensitivity of the ellipsometric response to the different factors in surrounding media.

The objectives of this efforts was to develop spectroscopic ellipsometry method for investigation of optical properties: (i) of multi-layered nanostructures used for Bovine leukaemia virus glycoprotein gp51 recognition, (ii) nanostructures consisting of monomeric (mGCSF) and dimeric (dGCSF) granulocyte colony stimulating factor and its receptor (GCSF-R) and (iii) Al2O3/ZnO nanolaminates designed by atomic layer deposition method. In particular, focusing on the investigation of: • biological recognition layers of immunosensors by means of comparison of analytical sensitivities of ellipsometric parameters Δ and Ψ in order to estimate differences in orientation of immobilized intact- and fragmented-antibodies against bovine leukemia virus antigen gp51; • the kinetics of biosensing layer formation, which was based on the immobilization of fragmented and intact antibodies, kinetics of antigen interaction with the immobilized antibodies and interactions of monomeric (mGCSF) and dimeric (dGCSF) granulocyte colony stimulating factor and its receptor (GCSF-R) immobilized on a thin gold layer; • kinetic coefficients of monomolecular biological layer formation process using model which takes into consideration partial reversibility (residence time) effect; • optical constants of Al2O3 and ZnO monolayer as well as Al2O3/ZnO nanolaminates prepared by atomic layer deposition method in order to investigate possibilities to apply these nanolaminates for optical biosensors. Spektroskopinės elipsometrijos metodas išvystytas ir pritaikytas (i) daugiasluoksnių nanostruktūrų, skirtų galvijų leukemijos viruso (GLV) antigeno gp51 aptikimui, (ii) nanostruktūrų, sudarytų iš monomerinio ir dimerinio granuliocitų kolonijas stimuliuojančio faktoriaus bei jų receptoriaus ir (iii) Al2O3/ZnO nanolaminatų, pagamintų atominių sluoksnių nusodinimo metodu, optinių savybių tyrimams • Tiriant elipsometrinių parametrų Δ ir Ψ jautrumą biojutikliuose, sudarytuose iš biologiškai aktyvių sluoksnių, nustatyti biomolekulių orientacijos skirtumai tarp sluoksnių, sudarytų iš imobilizuotų skaldytų ir neskaldytų antikūnų prieš GLV antigeną. • Ištirti biologiškai aktyvūs sluoksniai, sudaryti iš imobilizuotų skaldytų ir neskaldytų antikūnų prieš GLV antigeną sąveikos su antigenu gp51 ir granuliocitų kolonijas stimuliuojančio faktoriaus (GCSF) receptoriaus imobilizuoto ant aukso paviršiaus, sąveikos su GCSF monomeru ir dimeru formavimosi kinetikos. • Pritaikant modelį, įskaitantį negrįžtamos imobilizacijos reiškinį, nustatytos monomolekulinių biologinių sluoksnių iš antikūnų prieš GLV ir antigeno gp51 bei GCSF ir jo receptoriaus formavimosi kinetinės konstantos. • Nustatytos Al2O3 ir ZnO sluoksnių bei Al2O3/ZnO nanolaminatų, suformuotų naudojant atominių sluoksnių nusodinimo metodą, optines konstantos ir ištirtos galimybes šias struktūras panaudoti biojutikliuose.

Pastarąjį dešimtmetį, intensyviai vystantis nanotechnologijoms, ženkliai išaugo technologinių metodų, įgalinančių suformuoti darinius, kuriuose elementų dydžiai būtų tarp 1 ir 100 nm, paieška. Šiai specifinei nanostruktūrinių medžiagų grupei skiriamas ypatingas dėmesys dėl naujų fizikinių reiškinių ir ypač - praktinių taikymų, kuriuos atveria šie dariniai. Šiame darbe aptariamos elektrocheminės technologijos, skirtos kontroliuojamos morfologijos porėtojo silicio formavimui. Suformuoti hibridiniai por-Si dariniai su metalais. Sukurta biomolekulių įterpimo į porėtuosius silicio darinius technologija bei tirta biomolekulių sąveika su kietakūniais padėklais. Nagrinėjami GaP nanodarinių formavimo elektrocheminio ėsdinimo būdu dėsningumai bei jų taikymo galimybės dujų sensoriuose. Įsisavinta nanoporėtųjų dielektrinių terpių ir hibridinių nanodarinių formavimo technologija bei tirtos jų savybės. Over the past decade, the intensive development of nanotechnology was made to increase significantly the number of methods to form the structures of a size between 1 and 100 nm. It should be emphasized that nanostructured materials are interesting both because of perspectives in practical applications and new physical phenomena. In this work the electrochemical technique for the control of morphology of porous silicon matrix developed. Hybrid por-Si structures with metals were made. The method for infiltration of biomolecules into the porous silicon structures was developed and the interaction between silicon and bio-molecules was investigated. GaP nanostructures were formed by electrochemical etching and the possibilities of their application for gas sensors were estimated. Nanoporous and Fe-doped silica films on Si were made and the developed structures were characterized by their structural, optical or magnetic properties.

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.

V doktorski disertaciji je bil proučen vpliv protimikrobnega sredstva 3-(trimetoksisilil)-propildimetiloktadecil amonijevega klorida (TMPAC) na biorazgradljivost dveh celuloznih substratov. V prvem delu naloge je bila preiskana biorazgradljivost TMPAC obdelane bombažne tkanine v primerjavi z neobdelano ob uporabi vrstične elektronske mikroskopije, FT-IR ATR spektroskopije, diferenčne dinamične kalorimetrije in z določanjem izgube mase. Iz rezultatov je bilo razvidno, da protimikrobno sredstvo TMPAC zmanjšuje stopnjo razgradnje bombažne tkanine, kar je bilo dokazano predvsem z morfološkimi in kemijskimi spremembami med procesom razgradnje. Kemijske spremembe so bile raziskane s pomočjo FT-IR ATR spektroskopije in dokazane zlasti s prisotnostjo amidnih in karboksilnih funkcionalnih skupin. Amidne funkcionalne skupine so nastale kot posledica prisotnosti proteinov nastalih z mikrobno rastjo, medtem, ko so karboksilne funkcionalne skupine nastale kot posledica oksidativne razgradnje celuloze. Dejstvo, da protimikrobno sredstvo TMPAC znižuje stopnjo razgradnje bombažne tkanine je bilo pojasnjeno z močno hidrofobnim značajem TMPAC obdelane površine, kar smo dokazali z večjim stičnim kotom TMPAC obdelanega bombaža v primerjavi z neobdelanim. V drugem delu naloge je bila proučena encimska razgradnja modelnega celuloznega filma obdelanega s protimikrobnim sredstvom TMPAC, v primerjavi z neobdelanim filmom ob uporabi mikroskopije na atomsko silo in elipsometrije. Uporabljene celulaze so bile pridobljene iz gliv Trichoderma viride in Aspergillus niger. Po dodatku encimov k modelnemu celuloznemu filmu, je po začetni adsorpciji encimov na substrat sledila nadaljnja razgradnja celuloze. Encimska razgradnja celuloze je bila dokazana s konstantno izgubo v masi filma ter z ne-monotonim obnašanjem v debelini filma, ki dokazuje, da encimi ne razgrajujejo samo površine filma ampak tudi penetrirajo v film. Učinkovitost uporabljenih celulaz je bila različna in veliko višja stopnja razgradnje je bila opažena pri uporabi celulaze Trichoderma viride. Stopnja razgradnje se je ob uporabi te celulaze očitno znižala, ko je bil celulozni film predhodno obdelan s protimikrobnim sredstvom TMPAC, medtem, ko pa protimikrobno sredstvo ni imelo pomembnega učinka na razgradnjo ob prisotnosti celulaze Aspergillus niger. Dokazano je bilo, da v odvisnosti od tipa celulaze, protimikrobno sredstvo TMPAC zavira encimsko učinkovitost na fazni meji trdno-tekoče. TMPAC povzroča hidrofobnost modelnega celuloznega filma in s tem zavira adsorpcijo encimov na površino substrata. ABSTRACT The influence of the antimicrobial agent 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (TMPAC) on the biodegradation of two cellulose substrates was studied. Firstly, the biodegradation of TMPAC treated cotton fabric in comparison with untreated cotton fabric was investigated using Scanning Electron Microscopy (SEM), weight loss measurements, Fourier Transform Infrared Attenuated Total Reflectance (FT-IR ATR) spectroscopy and Differential Scanning Calorimetry (DSC). It was observed that the antimicrobial agent TMPAC decreases the degradation rate of the cotton fabric which was proven mostly by the morphological and chemical changes throughout the biodegradation process. The chemical changes were investigated by using FT-IR ATR spectroscopy and proven by the presence of amide groups as well as by the presence of carboxylic functional groups. Amide groups were produced as consequence of the proteins produced by microbial growth meanwhile the carboxylic groups were produced as consequence of oxidative degradation of cellulose. The fact that the antimicrobial agent TMPAC decreases the degradation rate of cotton fabric is explained by the strong hydrophobic character of the TMPAC treated surface which was proven by the higher contact angle for TMPAC treated cotton in comparison with untreated cotton fabrics. Secondly, the enzymatic degradation of model cellulose film treated with antimicrobial agent (TMPAC) in comparison with pure cellulose film was investigated by Atomic Force Microscopy (AFM) and by in situ-null ellipsometry. The cellulases used were extracted from Trichoderma viride and Aspergillus niger. After enzyme addition to the previously equilibrated cellulose film, the initial enzyme adsorption on the substrate was followed by the cellulose film degradation. The enzymatic degradation of cellulose was proven by a constant loss of the film mass and a non-monotonous behaviour of the film thickness which suggest that the enzymes degrade not only the top of the surface but also penetrate into the cellulose film. The activities of the two enzymes were different, a much higher degradation rate being observed for the Trichoderma viride cellulase. The degradation rate with this cellulase decreased significantly when the cellulose film was treated with the antimicrobial agent TMPAC, meanwhile the antimicrobial agent did not affect the cellulose degradation significantly in the presence of Aspergillus niger cellulase. Hence, it was demonstrated for the first time that, depending on the cellulase type, the antimicrobial agent can inhibit enzymatic activity at the solid-liquid interface. TMPAC causes hydrophobicity of the model cellulose film and thus inhibits the adsorption of the enzymes on the surface.

Tirta ErMnO3 optinės savybės: apskaičiuotos dielektrinių skvarbų spektrinės priklausomybės, optinių šuolių energijos, lūžio ir sugerties rodikliai. Tyrimai atlikti elipsometru, dielektrinė funkcija apskaičiuojama pagal vienašio kristalo modelį. Manganites have attracted a lot of attention due to their magnetical properties: colossal magnetoresistance, variety of phase, but the optical properties of ErMnO3 were not widely investigated. Investigation of optical properties of ErMnO3 single crystal were studie by means of ellipsometry method. Ellipsometric studies have been carried out in the spectral range of 1- 5 eV. The photimetric ellipsometer with rotating analyzer was used. Experimental ellipsometer data were analysed in the isotropical and uniaxial crystal models. The optical properties of ErMnO3 were investigated: ellipsometric parameters Ψ and Δ were determinated, the components of dielectric function and energy of optical transition were found, calculated refractive and absorption indexs.

U radu je primijenjena elipsometrijska metoda mjerenja debljine sloja SiO2 u sustavu okolina-SiO2-Si, primjenom reflektirajućeg elipsometra AUTOEL-III. Mjerenja su izvršena na osam baždarnih etalona hrapavosti Laboratorija za precizna mjerenja dužina (LFSB), u cilju određivanja dubina brazde i ocjene homogenosti pokrovnog sloja SiO2.