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Uvod: Kombinacija dveh ali več dentalnih zlitin v ustni votlini, ki so v stiku s slino lahko privede do medsebojnih interakcij in nastanka korozijskih produktov. Ti produkti so kovinski ioni, ki se sproščajo v telo in lahko povzročijo morebitne zaplete pri pacientu. (Ciszewski et al., 2007) Korozija je elektrokemijski proces, kjer pride do električnega toka med kovinami skozi elektrolit. Gonilno silo korozije predstavlja razlika potencialov med temi kovinami. (Milošev, 1994) V takšnem primeru je potrebno primarni material zamenjati z drugim. Druga rešitev je pasivacija površine primarnega materiala. Ena od tehnik pasiviranja površine je galvanska pozlatitev, kjer se na material nanese zlata plast. (Faber, n .d.) Namen: Predstaviti želimo tehnološki postopek galvanizacije s ciljem pasivacije površine. Na vzorcih pozlačene kovinske baze delne proteze iz Co-Cr zlitine smo pod mikroskopom preverili mikrostrukturo Co-Cr zlitine in zlata, njuno vezavo in debelino pozlate. Metode dela: Teoretični del diplomskega dela temelji na osnovi pregledane domače in tuje literature. Literaturo smo iskali v knjižnicah in elektronskih podatkovnih bazah. Praktični del diplomskega dela obsega izdelavo delne proteze s kovinsko bazo iz Co-Cr zlitine, njeno pozlato in metalografsko analizo vzorcev pozlačene kovinske baze. Pod mikroskopom smo raziskali mikrostrukturo pozlate, morebitne napake v mikrostrukturi in njeno debelino. Želeli smo ugotoviti, ali je zlata plast zvezna in kompaktna. Preučili smo tudi mikrostrukturo mejne površine med Co-Cr zlitino in pozlato. Rezultati: Pri metalografski analizi vzorcev smo naleteli na napako v mikrostrukturi pozlate vzorca podjezičnega loka, ki izgleda kot poroznost. Na mejni površini med Co-Cr zlitino in pozlato nismo našli napak v mikrostrukturi. Pri merjenju debeline pozlate smo prišli do ugotovitev, da je pozlata na lokalnih območjih enakomerno debela, vendar se debelina po celotni konstrukciji razlikuje. Pozlata na molarski zaponi je debelejša kot na podjezičnem loku. Razprava in zaključek: Menimo, da napaka v mikrostrukturi pozlate predstavlja poškodovan del pozlate, ki je nastal pri obdelavi površine metalografskega vzorca. Če je napaka nastala pri tehnološkem postopku pozlate, ta predstavlja neprekrito površino konstrukcije iz Co-Cr zlitine, kar posledično ne bi preprečilo nadaljnjega sproščanja kovinskih ionov. Vzrok za odstopanje v debelini pozlate po konstrukciji je premikanje konstrukcije pri mešanju elektrolita med končno pozlato kovinske baze. Introduction: The combination of two or more dental alloys in the oral cavity, which are in contact with saliva, can lead to mutual interactions and the formation of corrosion products. These products are metal ions that are released into the body and can cause potential complications for the patient. (Ciszewski at al., 2007) Corrosion is an electrochemical process where an electric current occurs between metals through an electrolyte. The driving force of corrosion is the potential difference between these metals. (Milošev, 1994) In such a case, it is necessary to replace the primary material with another. Additional solution is to passivate the surface of the primary material. One of the surface passivation techniques is galvanic gilding, where a gold layer is applied to the material. (Faber, n.d.) Purpose: We would like to present the technological process of electroplating with the aim of passivating the surface. The microstructure of the Co-Cr alloy and gold, their bonding and the thickness of the gilding were checked by stereo, light and scanning electron mictoscope on the samples of the gilded metal base of the partial prosthesis made of Co-Cr alloy. Work methods: The theoretical part of the thesis is based on the reviewed domestic and foreign literature. Literature was searched in libraries and electronic databases. The practical part of the thesis includes the production of a partial prosthesis with a metal base made of Co-Cr alloy, its gilding and metallographic analysis of samples of the gilded metal base. We investigated the microstructure of the gilding, possible defects in the microstructure and its thickness by stereo, light and scanning electron mictoscope. We wanted to find out if the gold layer is continuous and compact. We also examined the microstructure of the boundary surface between the Co-Cr alloy and gold plating. Results: During the metallographic analysis of the samples, we encountered a defect in the microstructure of the gilded sublingual arch sample, which looks like porosity. No defects in the microstructure were found on the interface between the Co-Cr alloy and the gilding. When measuring the thickness of the gilding, we came to the conclusion that the gilding is uniformly thick in local areas, but the thickness varies throughout the entire structure. The gilding on the molar clasp is thicker than on the sublingual arch. Discussion and conclusion: We believe that the defect in the microstructure of the gilding represents a damaged part of the gilding that occurred during the surface treatment of the metallographic sample. If the defect occurred during the technological process of gilding, it represents an uncovered surface of the Co-Cr alloy structure, which would not prevent the further release of metal ions. The reason for the deviation in the thickness of the gilding after the construction is in the movement of the construction during the mixing of the electrolyte during the final gilding of the metal base.

5 ABSTRACT Charles University, Faculty of Pharmacy in Hradci Králové Department of Organic and Bioorganic Chemistry Candidate: Petr Makaj Supervisor: PharmDr. Petr Matouš, Ph.D Title of Thesis: Synthesis of Ortho-Condensed Nitrogen Heterocycles Using Gold Complexes This diploma thesis is focused on the preparation of pyridopyridine derivatives using gold-catalyzed cyclizations. The synthesis is based on MBS-protected propargylamine, which after substitution with aryl using Sonogashira coupling reacts with tert-butyl (3- oxopent-4-ynyl)carbamate to form substituted 1,5-enyne. The enyne thus prepared then undergoes cycloisomerization using tris(2- furanyl)phosphinegold(I)chloride as a catalyst to form pyridopyridine. Substances with this scaffold can be further used to synthesize potentially biologically active structures. Keywords: gold catalysis, cyclization, pyridopyridine derivatives, 1,8-naphthyridine derivatives

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of organic and bioorganic chemistry Candidate: Bartoloměj Grobař Supervisor: PharmDr. Petr Matouš, Ph.D. Title of thesis: Synthesis and reactivity of enyns with terminal double bond This work focuses on synthesis of structures containing terminal vinyl moiety and their subsequent reactivity. We tested various approaches that lead to formation of enynes, which are then cyclized using gold complex catalyst into tetrahydropyridines. Both utilize the addition of propargylamine protected by 4-methoxybenzenesulfonyl group to substituted butynone and methoxyphenyl propiolates. Tetrahydropyridine molecules that are successfully created, are further derivatized forming polycyclic structures.

Charles University in Prague Faculty of Pharmacy in Hradec Králové Candidate: Patrik Sedláček Supervisor: PharmDr. Petr Matouš, Ph.D. Title of thesis: Synthesis of Chromeno[3,4-c]pyridines with New All-Carbon Quaternary Centre This diploma thesis focuses on the synthesis of 3,4-disubstituted pyridine derivatives and their subsequent cyclization to form chromeno[3,4-c]pyridine derivatives with a new all-carbon quaternary center. Phenyl-propiolate reacts with an aryl-substituted propargyl amine protected with 4- methoxybenzenesulfonyl group to form a 1,5-enyne. Substituted 1,5-enyne undergoes intramolecular cyclization catalyzed by tri(2-furyl)phosphinogold(I)chloride [AuCl(TFP)] to form the corresponding dihydropyridine. In the presenece of concentrated H2SO4, dihydropyridine undergoes carbocyclization forming the corresponding chromenopyridine with a new all-carbon quaternary center. The compounds prepared and their derivatives could find application as potentially biologically active substances and intermediates in organic synthesis.

In a search for novel antimicrobial metal-based therapeutic agents, mononuclear gold(III) complexes 1–7 of the general formula [AuCl$_3$(azole)], where azole stands for imidazole (im, 1), 1-isopropylimidazole (ipim, 2), 1-phenylimidazole (phim, 3), clotrimazole (ctz, 4), econazole (ecz, 5), tioconazole (tcz, 6) and voriconazole (vcz, 7) were synthesized, characterized and biologically evaluated. In all complexes, the corresponding azole ligand is monodentately coordinated to the Au(III) via the imidazole or triazole nitrogen atom, while the remaining coordination sites are occupied by chloride anions leading to the square-planar arrangement. In vitro antimicrobial assays showed that the complexation of inactive azoles, imidazole, 1-isopropylimidazole and 1-phenylimidazole, to the Au(III) ion led to complexes 1–3, respectively, with moderate activity against the investigated strains and low cytotoxicity on the human normal lung fibroblast cell line (MRC-5). Moreover, gold(III) complexes 4–7 with clinically used antifungal agents clotrimazole, econazole, tioconazole and voriconazole, respectively, have, in most cases, enhanced antimicrobial effectiveness relative to the corresponding azoles, with the best improvement achieved after complexation of tioconazole (6) and voriconazole (7). The complexes 4–7 and the corresponding antifungal azoles inhibited the growth of dermatophyte Microsporum canis at 50 and 25 μg mL$^{−1}$. Gold(III) complexes 1–3 significantly reduced the amount of ergosterol in the cell membrane of Candida albicans at the subinhibitory concentration of 0.5 × MIC (minimal inhibitory concentration), while the corresponding imidazole ligands did not significantly affect the ergosterol content, indicating that the mechanism of action of the gold(III)–azole complexes is associated with inhibition of ergosterol biosynthesis. Finally, complexes 5 and 6 significantly reduced the production of pyocyanin, a virulence factor in Pseudomonas aeruginosa controlled by quorum sensing, and increased cell survival after exposure to this bacterium. These findings could be of importance for the development of novel gold(III)-based antivirulence therapeutic agents that attenuate virulence without pronounced effect on the growth of the pathogens, offering a lower risk for resistance development.

V okviru diplomske naloge sem pregledala znanstveno literaturo za postopke sintez kovinskih kompleksov 6-metoksikinolina z zlatom(I/III) oziroma platino(II). Enake sintezne postopke sem po preizkušenih reakcijah s 6-metoksikinolinom preizkusila še z molekulo dihidrokinidina. Pri tem sem v reakcijah spreminjala reakcijske pogoje in sinteze preizkušala z uporabo različnih topil. Večino reakcij sem opravljala v temi zaradi občutljivosti na svetlobo zlatovih in platinskih soli. Cilj diplomske naloge je bil pripraviti kompleks 6-metoksikinolina ali dihidrokinidina z zlatom oziroma platino brez nečistoč. Sintetizirane produkte sem okarakterizirala z NMR, masno spektrometrijo in rentgensko strukturno analizo. As part of my diploma thesis, I reviewed the scientific literature for the synthesis procedures of metal complexes of 6-methoxyquinoline with gold(I/III) and platinum(II). After the tested reactions with 6-methoxyquinoline, I tried the same synthesis procedures with the dihydroquinidine molecule. While doing that, I changed the reaction conditions in the reactions and tested the syntheses using different solvents. Most of the reactions were preformed in the dark, due to the light sensitivity of gold and platinum salts. The goal of my thesis was to prepare a complex of 6-methoxyquinoline or dihydroquinidine with gold or platinum without impurities. I characterized the synthesized products by NMR, mass spectrometry and X-ray structural analysis.

V doktorskem delu smo predstavili nekatere nove sintezne metode, spojine, reagente v okviru organske kemije halogenov in halkogenov s poudarkom na načelih zelene kemije in trajnostnem razvoju. Zaradi netrajnostne rabe naravnih virov in onesnaževanja okolja se je razvilo področje, imenovano zelena kemija, ki temelji na okolju prijaznih principih. Med hal(k)ogeniranimi organskimi spojinami najdemo mnoge materiale, topila, reagente, sintone in naravne spojine ter medicinsko, industrijsko in agrokemijsko pomembne spojine. Kljub hitremu napredku na področju, se pojavljajo potrebe po sintezi obstoječih in novih motivov pod alternativnimi pogoji, ki sledijo načelom trajnostnega razvoja. Organske sulfokside smo do sulfidov reducirali na vodnem mediju 37% HCl s cenenim reagentom NaSH, ki po koncu reakcije tvori okolju nenevarne odpadne produkte. Produkt reakcije v večjem merilu smo izolirali z neposredno destilacijo. Razvili smo novo, hitro in priročno metodo oksidacije organskih sulfidov, ki pri zelenih pogojih slelektivno poteka s t-BuOCl. Pretvorbe so odvisne od temperature in topila, sulfokside in sulfone pa smo izolirali z odstranitvijo topila in hlapnih primesi. Metodo smo prenesli na večje merilo in na polimerne substrate ter raziskovali mehanizem. Prej neznane N-jodo sulfoksimine smo pripravili neposredno iz sulfidov z eno-lončnim sintetskim pristopom v zelenem topilu metanolu. Metodo smo izvedli v večjem merilu in predstavili nekatere nadaljnje pretvorbe. Organske selenide smo do selenoksidov oksidirali s 30% vodno raztopino zelenega oksidanta H2O2. Pripravili smo dva reagenta za elektrofilno selenocianiranje in -SeCN uvedli pod trajsnotnimi pogoji. 2-Amino-4H-pirane smo pod reakcijskimi pogoji brez topil s t-BuOCl regioselektivno klorofukcionalizirali do α,N-dikloroiminov in produkte izolirali z odstranjevanjem hlapnih primesi. Zlato smo raztopili v etanolu s katalitsko količino joda, 33% vodne raztopine H2O2 ter cenenim in nenevarnim ligandom. Doktorska naloga predstavlja pomemben doprinos k zeleni kemiji redoks reakcij žveplovih in selenovih organskih spojin, elektrofilnega prenosa halogenov in halkogenov ter njihovih funkcionalnih skupin, sintezi in reaktivnosti haloiminskega stukturnega motiva in recikliranja dragocenih kovin. Herein we present some novel synthetic methods, compounds and reagents in the context of halogen and chalcogen organic chemistry with emphasis on green chemistry principles and sustainable development. Due to unsustainable exploitation of natural resources and environmental pollution, green chemistry was established on environmentally friendly principles. Halogenated and chalcogenated organic compounds are important materials, solvents, reagents, synthons and natural compounds, that are used in medicine, industry, and agrochemistry. Despite quick development of this field, there is still a great need for preparation of existing and novel motifs under alternative conditions that follow sustainable development. Organic sulfoxides were deoxygenated to sulfides using 37% aqueous HCl and affordable reagent NaSH, that produce environmentally benign waste. Product of scaled-up reaction was isolated by direct distillation. New, rapid, and convenient method for oxidation of organic sulfides that selectively proceeds with t-BuOCl under green reaction conditions. Reaction was temperature- and solvent-dependent and product sulfoxides and sulfones were isolated by removal of solvent. The method was easily scalable and tested on polymeric substrate. The mechanism was explored. Previously unknown N-iodo sulfoximines were prepared from sulfides via one-pot approach in green solvent methanol. The method was scaled-up and further transformations were explored. We developed new sustainable method for oxidation of organic selenides using 30% aqueous H2O2 solution. Two reagents for electrophilic selenocyanation were prepared and -SeCN motif was introduced under sustainable conditions. 2-Amino-4H-pyrans were regioselectively chloro-functionalised with t-BuOCl under neat reaction conditions to afford α,N-dichloroimines that were isolated by removal of volatiles. Gold was dissolved in ethanol with catalytic amount of iodine, 33% aqueous H2O2 and inexpensive and non-toxic ligand. Doctoral thesis presents an important contribution to green chemistry topics of sulfur and selenium organic compound redox reactions, halogen and chalcogen functional group electrophilic transfer and synthesis, reactivity of haloimine structural motif and noble metal recycling.

Istražena je SERS učinkovitost nanočestica srebra i zlata imobiliziranih na staklu silaniziranom (3- aminopropil)trimetoksisilanom, odnosno (3-merkaptopropil)trimetoksisilanom. Korištene nanočestice srebra i zlata pripremljene su redukcijom srebrova(I) nitrata hidroksilaminhidrokloridom, odnosno tetraklorozlatne(III) kiseline trinatrijevim citratom te je nastalim koloidima određena SERS aktivnost. Kao modelne molekule odabrani su metilensko modrilo (MetB) i 4- aminotiofenol (PATF) čiji su koncentracijski ovisni SERS spektri snimljeni pri valnim duljinama pobude 532 i 785 nm na svim priređenim SERS supstratima. U koloidu srebra, kod obje valne duljine pobude, molekule MetB adsorbiraju se na metal središnjim fenotiazinskim sustavom, vezujući se preko atoma dušika. Uočeno je da u koloidu srebra molekule PATF nakon pobude pri 532 nm katalitički dimeriziraju u 4,4'-dimerkaptoazobenzen, dok se kod pobude pri 785 nm uočava smjesa monomera i dimera u spektru. Pri pobudi od 785 nm u koloidu zlata opažene su spektralne promjene pri nižim koncentracijama MetB koje upućuju na promjenu orijentacije molekula na površini i vezanje na površinu zlata preko atoma sumpora. U odnosu na koloidne suspenzije, nanočestice srebra i zlata imobilizirane na silaiziranom staklu nisu se pokazale reproducibilnim supstratima zbog neravnomjerne raspodjele nanočestica metala na površini stakla i samo otopine najvećih koncentracija daju vrpce u SERS spektrima. The SERS efficiency of silver and gold nanoparticles immobilized on glass silanized with (3- aminopropyl)trimethoxysilane and (3-mercaptopropyl)trimethoxysilane was investigated. Nanoparticles were prepared by reducing silver(I) nitrate with hydroxylamine hydrochloride, and tetrachloroauric(III) acid with trisodium citrate, respectively. For the prepared colloids the SERS activity was determined, as well. Methylene blue (MetB) and 4-aminothiophenol (PATF) were used as model molecules, whose concentration-dependent SERS spectra were recorded at excitation of 532 and 785 nm. In colloidal silver, MetB molecules were adsorbed on metal by the central phenothiazine system, binding through the nitrogen atom. In silver colloid PATF molecules catalytically dimerize into 4,4'-dimercaptoazobenzene after excitation at 532 nm, while spectra obtained from 785 nm showed a mixture of monomers and dimers. Using the excitation of 785 nm in the gold colloid, spectral changes were observed at lower concentrations of MetB, indicating orientation changes on the surface and binding to the gold surface via sulphur atoms. Compared to nanoparticles in colloidal suspensions, silver and gold nanoparticles immobilized on silanized glass did not prove to be reproducible substrates due to the uneven distribution of metal nanoparticles on the glass surface, therefore only solutions of the highest concentrations gave bands in SERS spectra.

Elementarno zlato (kemijskog simbola Au) mekani je metal karakteristične žute boje i plošno centrirane kubične strukture. Čisto je zlato na zraku stabilno i općenito vrlo otporno na utjecaje iz okoliša. U prirodi se pojavljuje samo jedan stabilni izotop zlata (197Au) te šesnaest prirodnih radioaktivnih izotopa (198Au). Zlato se u današnje vrijeme koristi u izradi nakita, ukrasnih predmeta i površina (primjerice strop u crkvi), u matičnim pločama elektroničkih računala, a kadšto i umjetničkih skulptura. Od otkrića i početka rudarenja zlata (približno 5000 godina) ono se često koristilo kao opća vrijednost i ekvivalent novca, a u 19. i početku 20. stoljeća je služilo kao „zlatni standard“ u državnim trezorima i bankovnom sustavu. U prirodi se može pronaći u obliku grumena ili zrna u stijenama, zlatnim žilama na nalazištima ili u aluvijalnim (naplavnim) naslagama. Prije početka rudarenja zlatom potrebno je utvrditi gdje se točno plemeniti metal može pronaći, odnosno gdje mineralizira. Mineralizacija je hidrotermalno taloženje ekonomski važnih metala u stvaranju rudnog tijela ili slojeva. Postoje ključni procesi koji upravljaju stvaranjem minerala, te se oni objašnjavanju fizikalnim zakonima. Kako bi se što bolje lociralo nalazište zlata, njegovi se procesi mineralizacije objašnjavaju pomoću metode računalne geoznanosti. Postoji više postupaka rudarenja za dobivanje zlata. Najstariji i najjednostavniji postupak dobivanja zlata jest ispiranje iz taloga i mulja prirodnih voda. U današnje se vrijeme uglavnom dobiva industrijskim postupcima rudarenja na primarnim i sekundarnim nalazištima. Cilj ovog rada jest objasniti stvaranje minerala, predstaviti različite načine rudarenja zlatom te utvrditi utjecaj rudarenja zlatom na okoliš. U ovom radu obrađeni su različiti aspekti mineralogeneze zlata u Zemljinoj kori, tehnologija rudarenja, svojstava nalazišta te štetni utjecaji na okoliš. U radu se opisuju nepovoljni učinci rudarenja i pročišćavanja zlata na vodu, zrak i tlo te učinke na živa bića (biljke, kukce, druge životinje i ljude). Temeljem literaturnih izvora opisano je više rudarskim mjesta u različitim zemljama i kontinentima. Uočeni su zajednički ekološki problemi. Elemental gold (chemical symbol Au) is a tender metal with a characteristic yellow color and plane-centered cubic structure. Pure gold is stable on the air and resistant to environmental influences. There is only one stable isotope of gold (197Au) and sixteen radioactive isotopes (198Au). Gold is used in jewelry, decorative surfaces, paintings, in electronic devices and sometimes sculptures. Since discovery of gold and beging of its mining (roughly 5000 years ago) the gold was often used as a general value and the equivalent of money. In the 19th and 20th century it served as „the gold standard“ in the state tresuries and banking systems. In nature, it can be found as nuggets or grains in rocks, veins and alluvial deposits. Prior to the gold mining, it is necessary to determine where we can find the noble metal, or where it mineralizes. Mineralization is a hydrothermal precipitation of economically important metals in the ore body formation or layers. Key processes that direct the process of mineralization can be explained with physical laws. Processes of mineralization are explained with computational geoscience method in order to better locate gold deposit. There are number of processes of gold mining. The oldest process of obtainig gold is leaching with natural waters while nowadays we can mine it on primary or secundary deposits or industrial way. The goal of this study is to explain mineralization, present different ways of gold mining and to establish the impact of gold mining on the environment. In this study various aspects of gold mineralogenesis in the earth's crust technology of mining, mine characteristics and negative ecological effects are elaborated. Negative effects of mining gold extraction on water, air, soil and living organisms (plants, insects, other animals and people) are shortly summarised. Based on published sources we described several mining spot in various couctries and continents. There are general common ecological problems in all of them.

Nekatera dramska dela najnovejše slovenske in ruske dramatike so izrazito feministično angažirana, zato se poraja vprašanje, ali bi lahko govorili o feministični novi (novi) drami kot o literarni smeri. Da bi na to vprašanje lahko odgovorili, je treba natančno opredeliti literarnozgodovinske periodizacijske pojme, časovno zamejiti obdobje nove oz. nove nove drame v slovenskem in ruskem prostoru ter opisati značilnosti najnovejše dramatike, poiskati povezave med feminizmom in literaturo ter raziskati prodor in delo sodobnih slovenskih in ruskih dramatičark, ki so v dramatiko 21. stoletja vnesle tematsko-formalne novosti, nenazadnje pa izbrati, analizirati in primerjati nekaj sodobnih dram slovenskih ter ruskih dramatičark. Analiza in primerjava dram to jabolko, zlato Simone Semenič, Mama Asje Vološine, 28 dni Olge Šiljajeve ter #punceinpolpunce Jere Ivanc pokaže, da je v dramskih delih mogoče prepoznati zelo soroden umetniški izraz, in sicer podobna motivno-tematska določila (pluralnost motivov in tem, ki osvetljuje položaj ženske v družbi v zgodovini in danes, ter kritika falogocentrizma) in podobne formalno-slogovne odlike (prehod ženskih likov od objekta k subjektu performativna, ne več dramska pisava ter spet dramska pisava razgrajena ali delno razgrajena dramska forma). V izbranih delih sodobnih slovenskih in ruskih dramatičark je torej mogoče zaznati zelo primerljivo feministično angažirano (ne več dramsko oz. spet dramsko) novo dramatiko, ki pa jo bo mogoče natančneje klasificirati šele z zadostno časovno distanco. Some of the plays of contemporary Slovene and Russian playwrights are markedly feminist, so the question arises whether it can be talked about feminist new (new) drama as a literary trend. In order to be able to answer this question, it is necessary to precisely define periodization terms in literary history, limit the period of the new and new new drama in the Slovene and Russian literary space and describe the characteristics of the latest drama, find connections between feminism and literature, investigate the breakthrough and work of contemporary Slovene and Russian female playwrights who introduced thematic and formal innovations into the drama of the 21st century, and select, analyse and compare some contemporary plays written by Slovene and Russian female playwrights. Analysis and comparison of the plays this apple, made of gold by Simona Semenič, Mother by Asya Voloshina, 28 days by Olga Shilyayeva and #girlsandmoregirls or #girlsandhalfgirls (depending on the interpretation of the title) by Jera Ivanc show that it is possible to recognize a very similar artistic expression in all the plays, namely similar motive-thematic determinations (plurality of motives and themes, which shed a light on the position of women in society in history and today, and a critique of phallogocentrism), and similar formal-stylistic features (transition of female characters from object to subject performative, no longer dramatic text and again dramatic text deconstructed or partially deconstructed dramatic form). In the selected works of contemporary Slovenе and Russian female playwrights, it is therefore possible to perceive a very comparable feminist engaged (no longer dramatic or once again dramatic) new drama, which, however, will be able to be more precisely classified only with a sufficient distance in time.

Gold is a scarce element in the Earth’s crust but indispensable in modern electronic devices. New, sustainable methods of gold recycling are essential to meet the growing eco-social demand of gold. Here, we describe a simple, inexpensive, and environmentally benign dissolution of gold under mild conditions. Gold dissolves quantitatively in ethanol using 2-mercaptobenzimidazole as a ligand in the presence of a catalytic amount of iodine. Mechanistically, the dissolution of gold begins when I$_2$ oxidizes Au$^0$ and forms a [Au$^I$I$_2$]$^−$ species, which undergoes subsequent ligand-exchange reactions and forms a stable bis-ligand Au$^I$ complex. H$_2$O$_2$ oxidizes free iodide and regenerated I$_2$ returns back to the catalytic cycle. Addition of a reductant to the reaction mixture precipitates gold quantitatively and partially regenerates the ligand. We anticipate our work will open a new pathway to more sustainable metal recycling with the utilization of just catalytic amounts of reagents and green solvents.

М60 М64

Bitcoin is often compared to gold for its gold-like features such as a store of value, a limited supply, and a safe haven. However, due to Bitcoin's extreme price movements, investors might rather look for a safe haven against Bitcoin. In this thesis, we study such properties among traditional assets. Specifically, we analyze gold, oil, and stocks as safe havens for Bitcoin on a sample period from 2014 until March 2022. We find that gold acts as a strong safe haven suggesting gold's traditional role as a shelter during uncertainty holds also for this crypto asset. 1

Tehnogeno ležište bakra i zlata Staro flotacijsko jalovište – Bor je nastalo odlaganjem flotacijske jalovine koja je nastala preradom rude iz više rudnih tela Borskog ležišta bakra i zlata, različitih teksturno-strukturnih karakteristika, mineralnog sastava i sadržaja bakra i zlata. Manji deo flotacijske jalovine je nastao kao rezultat prerade rude bakra i zlata iz ležišta Lipa.Flotacijsko jalovište je formirano u razdoblju od 1929. do 1992.godine, pri čemu su u različitim periodima njegovog formiranja prerađivane rude sa različitim sadržajima bakra i zlata. Usled nesavršenosti tehnoloških postupaka prerade rude, njenih složenih mineraloško petroloških karakteristika i drugih faktora, iskorišćenja bakra i zlata su bila relativno niska.Prema raspoloživim podacima, u koncentrat bakra se izdvajalo svega oko 85% bakra iz primarne rude,dok je ostatak od oko 15% izdvajan u flotacijsku jalovinu. Slično je i sa drugim korisnim komponentama.Flotacijsko iskorišćenje zlata se kretalo između 20 i 30%.Tehnogeno ležište bakra i zlata Staro flotacijsko jalovište – Bor je istraživano istražnim bušenjem sa površine, po nepravilnoj mreži sa rastojanjimaod 20×40 m, 40×40 m, 50×100 m do 50×100 m. Ostvarena gustina istražnih radova je zadovoljavajuća za potrebe prostornog sagledavanja distribucije bakra i zlata, kao i procenu(proračun)količina rezervi tehnogene mineralne sirovine. Omogućava dobru preglednost analitičkih prostorno definisanih podataka, dobijanje pouzdane i kvalitetne računarski generisane grafičke dokumentacije. Tehnogeno ležište je istraženo na nivou rezevi B i C1 kategorije.Modelovanje distribucije bakra i zlata u tehnogenom ležištu Staro flotacijsko jalovište –Bor je izvršeno primenom računarske tehnologije. Obuhvatilo je detaljnu geološku i statističku analizu podataka o sadržajima bakra i zlata u analiziranim probama iz istražnih bušotina sa prostora Polja 1 i Polja 2, njihovo međusobno povezivanje u prostoru, statističku analizu preko koeficijenta varijacije, grafičku interpretaciju u vidu poprečnih i uzdužnih vertikalnih preseka, kao i analizu prostorne distribuciju po profilima i nivoima. Modelovanje distribucije bakra i zlata je izvršeno i putem blok-modela ležišta, kao najilustrativnijeg prikaza, a čiji su prethodno pomenuti elementi sastavni deo.Istraživanjima su utvrđeni relativno niski, ravnomerno distribuirani sadržaji bakra i zlata, što je i potvrđeno statističkom analizom. Veličina blokova pri interpretaciji blok modela ležišta je prilagođana fizičkim karakteristikama ležišta, raspodeli bakra i zlata, kao i karakteristikama planirane metode eksploatacije, dok je procena sadržaja bakra i zlata izvršena primenom metode krigovanja - metod unakrsne validacija (potvrda“Cross validation”), i određivanjem granica interpertacije podataka i procenom blokova u ležištu. Zaključeno je da proračunata količina rezervi tehnogene mineralne sirovine opravdava dalje aktivnosti na tehničko-ekonomskoj oceni radi sagledavanja mogućnosti njihove eventualne eksploatacije.

This master's thesis is focused on genetic relationships between Au-bearing ores and associated granodiorite porphyry dykes in Petrov and Bohuliby area in southwestern part of the Jílové ore district. Subvolcanic rocks with hydrothermally induced alteration and Au/bearing mineralization were characterized by petrography, mineralogy and crystallochemistry. Mutual genetic and textural relationships of studied materials were examined as well and were validated by biotite, arsenopyrite and chlorite empirical geothermometry. First identified generation of sulfide mineralization was formed at 360řC and consist of arsenopyrite, galenite and native gold. At circa 274řC porphyry mineral association was chloritized, and chlorite gangue crystallized. Second generation of sulfide mineralization precipitated at 264řC. Based on acquired data, granodiorite porphyry dikes were categorized to two separate genetic types, which have mutual origin in deep magma chamber of Central Bohemian Plutonic Complex but intruded non-contemporaneously.

Učinkovitost površinski pojačanog Ramanova raspršenja (SERS) nanočestica srebra i zlata dispergiranih u svježe pripravljenim i koncentriranim koloidima te imobiliziranih na staklu tretiranom s fluorovodičnom kiselinom i staklenom filter-papiru istraživana je pomoću metilenskog modrila (MetB) i rodamina B (RB) pri pobudama 532 i 785 nm. Koncentrirane koloidne suspenzije jače pojačavaju raspršenje zračenja boja u odnosu na svježe pripravljene koloide. U koncentriranom koloidu zlata pri pobudi 785 nm opažene spektralne promjene upućuju na drugačiju orijentaciju molekula MetB na površini zlata, u odnosu na koloid srebra. Atom sumpora iz fenotiazinskog sustava boje tvori kemijsku vezu sa zlatom, dok su u koloidu srebra molekule MetB vezane na supstrat preko atoma dušika fenotiazina. Kod svih korištenih supstrata pobuda pri 785 nm rezultira intenzivnim vrpcama MetB i RB, dok pobuda pri 532 nm daje vrpce slabijeg intenziteta za MetB, a vrpce RB zasjenjuje široka vrpca fluorescencije. U odnosu na koloidne suspenzije, nanočestice srebra i zlata imobilizirane na čvrstim podlogama nisu se pokazale reproducibilnim supstratima zbog neravnomjerne raspodjele nanočestica metala na površini supstrata. Efficiency of surface-enhanced Raman scattering (SERS) of silver and gold nanoparticles dispersed in freshly prepared and concentrated colloids, and immobilized on hydrofluoric acid-treated glass and glass-fiber filter paper was investigated using methylene blue (MetB) and rhodamine B (RB) at excitation of 532 and 785 nm. Concentrated colloidal suspensions intensified the scattering of dye radiation, compared to freshly prepared colloids. In the concentrated gold colloid at 785 nm, observed spectral changes indicated a different orientation of MetB molecules on metal surface, compared to the silver colloid. The sulfur atom from phenothiazine created a chemical bond with gold, while MetB molecules in the silver colloid were bonded to the substrate via phenothiazine nitrogen atom. For all used substrates, the excitation at 785 nm resulted in intense MetB and RB bands, while excitation at 532 nm yielded lower-intensity bands for MetB, and a wide fluorescence band that overlapped RB bands. Metal colloidal suspensions were more reproducible substrates than the solid substrates, due to the uneven distribution of nanoparticles on the solid substrates.

Zlato je gospodarsko in industrijsko pomembna kovina s širokim spektrom uporabnosti. Ta plemenita kovina je nepogrešljiva v zlatarstvu zaradi dobrih fizikalnih lastnosti, kot so dobra električna prevodnost, možnost preoblikovanja in stabilnost, zaradi in odpornosti proti koroziji pa je uporabna tudi v tehnološki uporabi. Ker ima zlato visoko in relativno stabilno vrednost, ima tudi velik monetarni pomen. Ob dejstvu, da je zlata na Zemlji v omejenih količinah in ker zemljine zaloge počasi pojenjajo, ima vedno večji pomen reciklaža zlata. Znanih je več metod raztapljanja zlata. Industrijsko najpomembnejše je raztapljanje v natrijevem (NaCN) in kalijevem (KCN) cianidu. Ker pa so cianidi nevarni in škodljivi za okolje, se bomo v diplomskem delu dotaknili predvsem uporabe zlatotopke. Pri predelavi in reciklaži zlata je pomembno tudi plemenitenje. Za to se uporabljata Millerjeva in Wohlwillova metoda rafinacije. Pri praktičnem delu diplomske naloge smo iz 58 odsluženih mobilnih telefonov reciklirali zlato z uporabo zlatotopke. Delo je obsegalo razstavitev mobilnih telefonov in sortiranje delov, ki so vsebovali zlato. Iz omenjenih delov smo zlato z uporabo mešanice klorovodikove kisline in vodikovega peroksida lužili, ga filtrirali in raztopili v zlatotopki. Iz raztopine smo nato zlato izločili z uporabo natrijevega metabisulfita in čistega cinka usedline smo stalili v elektro-uporovni komorni peči. Kovinski delec smo nato analizirali z XRF analizo in diferenčno vrstično kalorimetrijo. Gold is an economically and industrially important metal with a wide range of uses. This noble metal is indispensable in jewelry. It is also useful in technological applications due to good physical properties, such as good electrical conductivity, formability, stability, and corrosion resistance. Because gold has a high and relatively stable value, it has also very important monetary significance. Given the fact that the gold on Earth is in limited quantities and that Earth’s reserves are slowly depleting, the recycling of gold is becoming increasingly important. There are several known methods of dissolving gold. The dissolution in sodium (NaCN) and potassium (KCN) cyanide are the most important in the industry. However, since cyanides are dangerous and harmful to the environment, we will focus on the use of aqua regia in the bachelor's thesis. Refining is an important process in the processing and recycling of gold. For that purpose, Miller and Wohlwill methods are used. In the practical part of the bachelor's thesis, we recycled gold from 58 used mobile phones using aqua regia. The thesis involved disassembling mobile phones and sorting parts that contained gold. We separated gold from the mentioned parts using a mixture of hydrochloric acid and hydrogen peroxide. Gold was filtered and dissolved in aqua regia. Gold was then eliminated from the solution using sodium metabisulfite and pure zinc. The sediments were melted in an electric resistance chamber furnace. The metal particle was then analyzed by XRF analysis and differential scanning calorimetry.

This thesis is focused on orogenic gold deposits and placer gold deposits. The first part describes predispositions for formation of orogenic gold deposits and their place in time and space. Next part of this thesis discusses mechanisms of formation of secondary gold deposits, so called placers. Practical part of this thesis is studying the sites in the neighbourhood of Bezdružice in West Bohemia - paleoplacer in sand quarry near municipality Křivce, grove with old mine works near municipality Nová Ves and the creeks which surround the grove from north and south. The aim of this thesis is to define whether the gold nearby Nová Ves originates in the Carboniferous paleoplacers which are in the proximity of old mines or if it comes from primary deposit and was formed close to cinnabar mineralization. Specimens were analysed under optical microscope and by energy dispersive system coupled with SEM. These analyses helped to distinguish gold flakes from the creeks of Nová Ves and the gold flakes from paleoplacer.

The thesis deals with possibility of investing in precious metals (with a great focus on gold) as a way to have financial savings for retirement and comparing it with more widely used saving tools in the Czech Republic that are used for such purposes - sup-plementary pension insurance, life savings and more. The first part of this work looks at Czech pension system before and after its reforms and pointing out its unsustainability for the future. It then proceeds to look in history of investing in gold and analyze in great depth its benefits and disadvantages. The practical part was divided into financial analysis based on the example of the statistically average Czech citizen and a question-naire, which was attended by 288 respondents, mainly students or university graduates. Although the results of the work showed the suitability of gold and other precious met-als in the issue of financial security for retirement, we shouldn't also forger their disad-vantages when choosing them for this purpose. When creating a financial portfolio, one should think about involving a whole range of financial products - whether stock, bonds or its supplementation in the form of advantageous supplementary pension savings. Pre-cious metals undoubtedly have a place there, but they should be used primarily for their specific investment characteristics and advantages: as a hedge against inflation and mar-ket fluctuations of non-correlated financial instruments.

This diploma thesis deals with Czech portrait medals in the past and present. The aim was to map Czech medal portrait work from its origins in the Renaissance to the present. At the beginning, the work is focused on the precious metals from which the medals are made, gold and silver. The history of gold and silver is included in the theory. The concepts of numismatics or commemorative medals made of gold and silver as investment preservation of real value are clarified. We were interested in the overall artistic process of producing portrait medal into the final product. The historical development of medals in the Czech lands followed. In each period, important artists, medalists, and their work are mentioned. All chapters contain pictorial materials. The practical part is devoted to all existing mintages of Karel Gott, which is a unique medal investment. Along with him, contemporary medal artists are characterized in more detail. In the end, the first findings about the portrait medal are summarized. The work brings an overall view of portrait medal work. Medal making represents a specific area of fine and sculptural art. It is an artistic artifact that reflects our history. KEYWORDS medal, gold, silver, portrait medal, commemorative medal, numismatics, art mintage, collecting

Migracije su kroz povijest uvijek označavale promjene u područjima iseljavanja, a posebno u mjestima doseljavanja. Rad se bavi mikrohistorijskim prikazom iseljavanja s otoka Brača i općine Omiš u čileansku pokrajinu Magallanes. Cilj je objasniti razloge iseljavanja s otoka Brača i općine Omiš u čileansku pokrajinu Magallanes, kako je ovo iseljavanje utjecalo na demografski profil navedenih područja te na koji način su emigranti putovali do Južne Amerike i kako je izgledala zemlja u koju su došli?. Rad je podijeljen na šest poglavlja. Nakon uvoda, drugo i treće poglavlje sadrže analizu gospodarskog i demografskog stanja u Dalmaciji te na Braču i na omiškom području od 60-ih godina 19. stoljeća do 30-ih godina 20. stoljeća. S obzirom na to da je uglavnom priobalni dio općine Omiš sudjelovao u migriranju, posebno će biti naglašena povijest mjesta Mimice koje je imalo najviše emigranta s kopnenog područja. Četvrto poglavlje opisuje putovanje do Južne Amerike te kakvi su bili iseljenički i useljenički zakoni u zemljama gdje se migracija odvijala. Peto poglavlje sadrži analizu useljeničkih zanimanja i života u novoj sredini te prikazuje popis bračkih i omiških prezimena koji danas nose njihovi potomci u Magallanesu. Zadnje poglavlje je završni dio rada u kojem se daju odgovori na postavljena istraživačka pitanja. Migrations throughout history have always marked changes in areas of emigration, and especially in places of immigration. The paper deals with a microhistorical account of emigration from the island of Brač and the municipality of Omiš to the Chilean province of Magallanes. The aim is to explain the reasons for emigration from the island of Brač and the municipality of Omiš to the Chilean province of Magallanes, how this emigration affected the demographic profile of these areas and how emigrants traveled to South America and what the country they came to looked like ?. The paper is divided into six chapters. After the introduction, the second and third chapters contain an analysis of the economic and demographic situation in Dalmatia and on the island of Brač and in the Omis area from the 1860s to the 1930s. Considering that mainly the coastal part of the municipality of Omiš participated in the migration, the history of the town of Mimice, which had the most emigrants from the mainland, will be especially emphasized. The fourth chapter describes the journey to South America and what the immigration laws were like in the countries where the migrations took place. The fifth chapter contains an analysis of immigrant occupations and life in the new environment and shows a list of Brač and Omis surnames that their descendants bear today in Magallanes. The last chapter is the final part of the paper in which the research questions are answered.

The aim of this diploma thesis is to test the possibility of using the geoelectrical resistivity tomography in tracing mining areas within the territory of the medieval gold-mines "Na Kometě" in the Písek Mountains and subsequently, based on the measured data, to estimate the simplified characteristics of the bedrock to a depth of 16 metres. The student will get acquainted with the basic geophysical instrument ARES as well as the basic interpretation of the data. The diploma thesis deals with basic geophysical instruments as well as with the occurrence of gold in the territory of South Bohemia. The submitted thesis has 129 pages and is divided into ten chapters.

Proizvodnja i upotreba metalnih nanočestica u kontinuiranom je porastu. Konvencionalne metode njihove sinteze često koriste razne toksične kemikalije i čine upotrebu tako sintetiziranih nanočestica ograničenom u prehrambenoj i tekstilnoj industriji, medicini, farmaceutici, itd. Stoga je vrlo važno naći i ispitati nove metode sinteze metalnih nanočestica koji će rezultirati ekološki prihvatljivim nanočesticama, a jedna od takvih upravo je njihova enzimatska sinteza. Nanočestice zlata jedne su od najviše istraživanih i korištenih vrsta nanočestica. Koriste se u raznim područjima znanosti i tehnologije te posebice u medicini u raznim terapijskim i dijagnostičkim sustavima. U ovom radu sintetizirane su nanočestice zlata korištenjem enzima glukoza dehidrogenaze (Gc GDH), koji katalizira reakciju oksidacije glukoze i celobioza dehidrogenaze (Mt CDH), koji katalizira reakciju oksidacije celobioze. Ispitana je kinetika oba enzima u navedenim reakcijama te je promatran utjecaj iona zlata na aktivnost enzima. Kinetika je u oba slučaja opisana jednosupstratnom Michaelis-Menteničinom kinetikom uz kompetitivnu inhibiciju ionima zlata. Procijenjene konstante inhibicije upućuju na to kako je inhibicija ionima zlata značajnija u slučaju reakcije oksidacije glukoze uz Gc GDH u odnosu na oksidaciju celobioze uz Mt CDH. Provođenjem sinteze nanočestica zlata uz Mt CDH i reakciju oksidacije celobioze, zaključeno je kako je mehanizam nastajanja naonočestica zlata direktno povezan s kinetikom reakcije oksidacije. Za navedenu sintezu postavljen je matematički model koji se dobro slaže s eksperimentalno dobivenim rezultatima. Prilikom sinteze nanočestica uz Gc GDH i glukozu, utvrđeno je da mehanizam nastajanja nanočestica nije povezan s reakcijom oksidacije glukoze, već nanočestice zlata nastaju redukcijom iona zlata uz glukozu i aminokiseline koje grade enzim.