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Yellowing of plastic objects as a consequence of chemical degradation is a common heritage conservation challenge. In the case of poly(vinyl chloride) elimination of hydrogen chloride leads to the formation of polyene sequences that act as chromophores. The objective of this work was to quantitatively evaluate the rate of degradation observed as yellowing, as relevant to room conditions during long-term storage of heritage collections. Degradation was quantified as increase in the b* colour coordinate during accelerated degradation at 50 and 70 °C as a function of temperature, relative humidity, plasticizer content, and polymer molecular weight. The significance of each variable was investigated with multiple linear regression. Lower temperature, lower relative humidity, higher polymer molecular weight and higher plasticizer content were associated with lower degradation rates. The activation energy of 86 kJ/mol was calculated. The concept of ‘1- °C-equivalent’ is introduced to enable variable prioritisation from a heritage management aspect. The resulting model can be used to shape environmental management guidelines and identify the most vulnerable objects in heritage collections.

The increasing world's dependence on batteries demands a more precise and consistent monitoring of the battery state in order to increase its quality, reliability, lifetime and safety (QRLS). Conventional monitoring of Li-ion battery performance is carried out by combining empirical measurement of the extrinsic parameters with multipart modelling and approximation algorithms. A step forward would be enabling more reliable built-in sensing systems that allow collecting direct information, such as a degree of material degradation. The sensing technologies should be designed in a way of monitoring the most detrimental process for the battery cell. Transition metal dissolution is one of the more severe degradation processes affecting the performance of the whole Li-ion battery cell. It can be accelerated through different mechanisms, and its monitoring has been a topic of several studies in recent decades. In the present work, we looked for an approach for detection of dissolved transition metal ions. The solution was found through a built-in electrochemical sensor with scavenger moieties. We demonstrated that manganese ion-imprinted polymer (Mn(II)-IIP) deposited between two electrodes printed directly on the separator can be used as a sensing layer. The resistance changes of this sensing layer due to the coordination of the ion-imprinted polymer with dissolved manganese ions are monitored by electrochemical impedance spectroscopy. The sensor’s electrodes and sensing layer remain stable within the voltage range of battery cycling over a longer application time. The sensor performance was validated in the single-layer pouch cell using Li|LiMn2O4 chemistry. The sensors printed on the separator do not significantly alter the current production technology and, most importantly, have a negligible impact on the cell energy density. The shown approach is universal and can eventually be extended to the detection of other degradation products in the electrolyte. Additionally, the use of the current printing technology permits large-scale commercialization. In summary, this work presented a simple solution for monitoring battery degradation via an electrochemical sensor integrated in the separator. Vse večja odvisnost sveta od akumulatorjev zahteva njihov natančnejši in doslednejši nadzor na ravni celic. Cilj je izboljšanje njihove kakovosti, zanesljivosti, življenjske dobe in varnosti (QRLS). Konvencionalno spremljanje delovanja Li-ionskih celic izvajamo s kombiniranjem empiričnega merjenja zunanjih parametrov z modeliranjem in algoritmi. V zadnjem času predstavlja pomemben napredek omogočanje vgrajevanja zanesljivejših senzorskih tehnologij, ki zbirajo neposredne informacije, kot na primer stopnja degradacije materiala. Senzorske tehnologije morajo biti zasnovane tako, da spremljajo najbolj škodljiv proces znotraj celice. Raztapljanje prehodnih kovin je eden resnejših degradacijskih procesov in vpliva na delovanje celotne celice Li-ionskega akumulatorja. Različni mehanizmi ga lahko pospešijo, spremljanje pojava pa je tema številnih raziskav zadnjih desetletjih. Tekom raziskovalnega dela smo iskali primeren pristop za detekcijo raztopljenih ionov prehodnih kovin. Rešitev, predstavljena v tej doktorski disertaciji je v obliki elektrokemijskega senzorja na osnovi polimera, ki preferenčno koordinira manganove ione (Mn(II)-IIP). Elektrokemijski senzor je pripravljen s tehnologijo tiskanja elektrod na separator. Med elektrodama je nanešen polimer, ki preferenčno veže manganove ione. Med vezavo se spremenijo fizikalno kemijske lastnosti, spremembe je možno zaznati z uporabo elektrokemijske impedančne spektroskopije. Senzor (tiskani elektrodi in zaznavna plast) je stabilen v napetostnem oknu uporabe akumulatorja. Učinkovitost senzorja je bila potrjena v laboratorijskem Li-ionskem akumulatorju, ki je bil sestavljen iz LiMn2O4 katode in kovinske litijeve anode. Senzorji, natisnjeni na separatorju, bistveno ne spreminjajo trenutne proizvodne tehnologije in, kar je najpomembneje, zanemarljivo vplivajo na energijsko gostoto celice. Prikazani pristop je univerzalen in ga je mogoče sčasoma razširiti tudi na detekcijo drugih produktov degradacije prisotnih v elektrolitu. Poleg tega uporaba trenutne tehnologije tiskanja omogoča obsežno komercializacijo. Če povzamemo, je to delo predstavilo preprosto rešitev za spremljanje degradacijskih procesov v akumulatorju s pomočjo elektrokemijskega senzorja, integriranega v separator.

Površinsko aktivne snovi (PAS) so pomožne snovi, ki se uporabljajo v bioloških formulacijah. Njihove glavne naloge so stabilizacija in zaščita proteina pred agregacijo in denaturacijo zaradi medfaznih obremenitev, ki se pojavijo med proizvodnim procesom, preprečujejo pa tudi adsorpcijo proteina in posledično njegove izgube na površinah, kot so filtri, cevke, primarni vsebniki in kompleti za intravensko aplikacijo. Najpogosteje zastopani PAS v bioloških formulacijah sta polisorbat 20 (PS20) in polisorbat 80 (PS80). V zadnjih letih se farmacevtska industrija srečuje z velikimi problemi zaradi njune heterogenosti in nestabilnosti v tekočih proteinskih formulacijah, kar vodi do zmanjšanja njune koncentracije in posledično zmanjšanja zaščitne funkcije na protein. Prav tako lahko produkti razgradnje PS20 in PS80 neposredno vplivajo na stabilnost in kakovost zdravila. Glavni poti razgradnje polisorbatov (PS) sta avtooksidacija in hidroliza, pri čemer je lahko hidroliza kemijskega ali encimskega izvora. Prav nestabilnost PS pa je vodila v iskanje možnih alternativnih PAS, ki bi jih bilo potencialno možno uporabiti v proteinskih formulacijah. S tem namenom smo znotraj magistrske naloge izbrali 7 komercialno dostopnih alternativnih PAS (Brij-58, TPGS-1000, poloksamer 188, Kolliphor ELP, SPGS-550-M, polioksi-32 stearate in poli(etilenglikol) monooleat), ki še niso bili uporabljeni kot pomožna snov v bioloških zdravilih na trgu. Alternativne PAS smo v prvem delu naloge izpostavili 4 različnim pufrom, z dvema različnima pH vrednostima, ki se najpogosteje uporabljajo v parenteralnih izdelkih, in jih izpostavili povišani temperaturi za en in dva meseca. V drugem delu smo alternativne PAS izpostavili vodikovemu peroksidu in železovem (III) kloridu, s čimer smo želeli ugotoviti, ali pride do oksidacije PAS in kakšni razgradni produkti nastanejo. Prav tako smo z natrijevim hidroksidom, klorovodikovo kislino in pufrom s pH 11 želeli spodbuditi kislinsko in bazično hidrolizo ter analizirati razgradne produkte. PAS smo analizirali z metodami tekočinske kromatografije visoke ločljivosti (HPLC), razvitimi za PS, pri čemer smo ovrednotili tudi ustreznost posamezne metode za določanje koncentracije in čistote za posamezno PAS. PAS smo analizirali tudi s tekočinsko kromatografijo sklopljeno z masno spektrometrijo (LC-MS). Pri vseh eksperimentih smo za primerjavo uporabljali PS80. Na koncu smo vsako PAS primerjali s PS80 in ugotovili, katera je najbolj stabilna proti oksidaciji in hidrolizi. Surfactants are excipients used in biological formulations. Their main tasks are to stabilize and protect the protein from aggregation and denaturation due to interfacial stresses that occur during the production process, but also prevent protein adsorption and subsequent protein loss on surfaces such as filters, tubes, primary containers and sets for intravenous administration. The most frequently represented surfactants in biological formulations are polysorbate 20 and polysorbate 80. In recent years, the pharmaceutical industry has faced major problems due to their heterogeneity and instability in liquid protein formulations, which leads to a decrease in their concentration and, consequently, protective functions on the protein and the direct impact of degradation products on the stability and quality of the drug. The main degradation pathways of polysorbates are auto-oxidation and hydrolysis, whereby hydrolysis can be of chemical or enzymatic origin. It was the instability of polysorbates that led to the research of possible alternative surfactants that could potentially be used in protein formulations. With this aim, we selected 7 commercially available alternative surfactants (Brij-58, TPGS-1000, Poloxamer 188, Kolliphor ELP, SPGS-550-M, polyoxy-32 stearate and poly (ethylene glycol) monooleate) within the master's thesis, which had not yet been used as an excipient in marketed biological medicines. In the first part of the task, we exposed alternative surfactants to 4 different buffers, with two different pH values, which are most often used in parenteral products, and exposed them to elevated temperature for one and two months. In the second part, we exposed alternative surfactants to hydrogen peroxide and iron (III) chloride, with which we wanted to find out whether the oxidation of surfactants occurs and what their breakdown products are. We also wanted to stimulate acid and basic hydrolysis with sodium hydroxide, hydrochloric acid and buffer with pH 11, and analyse the degradation products. Surfactants were analysed using HPLC methods developed for polysorbates, while we also evaluated the appropriate individual methods for determining the concentration and purity of each one. They were also analysed by LC-MS. PS80 was used for comparison in all experiments. In the end, we compared each surfactant with PS80 and found out which of the 7 selected shows the greatest stability in terms of oxidation and hydrolysis.

Naloga obsega pregled elementov zgornjega ustroja železniške proge, meritve parametrov in analizo vpliva geometrijskih elementov na vrednosti parametrov. V prvem delu naloge je predstavljen potek degradacije zgornjega ustroja. Opisani so elementi, ki sestavljajo zgornji ustroj in predstavljene zahteve, ki jih za posamezni element določajo standardi in pravilniki. V drugem delu naloge so predstavljeni merilni vlaki, ki izvajajo meritve na slovenskem železniškem sistemu. Predstavljeni so vlaki, ki merijo stanje tirnice in vlaki, ki merijo stanje tira. Za posamezne merjene parametre tira so opisane zahteve, ki jih določa Pravilnik o zgornjem ustroju železniških prog (2010). V zadnjem delu naloge so analizirane meritve, ki so se izvajale na železniški progi št. 50 Ljubljana–Sežana–d.m., na odseku Ljubljana–Postojna. Na splošno je predstavljena geometrija odseka Ljubljana–Postojna ter druge značilnosti na obravnavanem odseku. Analiziran je vpliv geometrijskih elementov in elementov zgornjega ustroja na napako tirne širine, vegavost in razvoj posedkov. This thesis presents railway track components, track measuring and analysis of track components and it’s influence on track degradation. First part of thesis presents degradation of track and description of track components. Special requirements that are defined by standards and regulations are described for each track component. Second part of thesis presents measuring trains that do measuring on Slovenian railway system. Measuring trains that are represented can measure conditions of rail and conditions of track. This part also describes the regulations for measured parameters that are required with Pravilnik o zgornjem ustroju železniških prog (2010). The last part of thesis describes the analysis of measured parameters on railway line number 50 Ljubljana–Sežana–d.m. between Ljubljana and Postojna. The geometry and other characteristics of line no. 50 from Ljubljana to Postojna are represented. The effects of superelevation, lateral acceleration and curve radius on track gauge are represented. It is checked how the average track gauge, rail twist and settlements develop depending of curve radius.

S pomočjo strokovne literature in referenčnih primerov se v magistrskem delu posvetim povezavi med degradiranimi območji ter nastankom urbanih toplotnih otokov. Glavni cilj magistrske naloge je, da na podlagi različnih pridobljenih informacij obravnavano degradirano območje sprojektiram na način, da to čim manj vpliva na pregrevanje prostora in nastanek toplotnih otokov. V zadnjih letih je nujno potrebno pri načrtovanju upoštevati klimatske kazalce, saj na ta način pripomoremo k zmanjševanju podnebnih sprememb. Pri projektnem delu je predstavljen koncept urbane rešitve, kjer je bila nekdanja tovarna Arrigoni v Izoli. V trenutno degradiranem prostoru se ponovno vzpostavi ribiški duh mesta, ki je včasih vladal v Izoli. V obravnavano območje umestim proizvodnje dejavnosti za pridelavo ribjih izdelkov in vina. S tem v prostoru poleg identitete mesta zagotovim nova delovna mesta in zanimivo turistično točko. S prepletom proizvodnih, poslovnih in centralnih dejavnosti ter odprtim javnim prostorom se na lokaciji zagotovi mešana raba namenjena različnim uporabnikom prostora. Pri projektiranju nove ureditve v prostoru upoštevam usmeritve za zmanjševanje nastanka toplotnih urbanih otokov, ki negativno vplivajo na kvaliteto življenja v prostoru ter na podnebne spremembe. With the help of professional literature and reference cases, I devote myself in my master's thesis the connection between degraded areas and the formation of urban heat islands. Main goal of the master's thesis is to be considered degraded based on the various information obtained I design the area in such a way that it has as little influence on the overheating of the room and the creation heat islands. In recent years, it is absolutely necessary to take climate indicators into account when planning, because in this way we help to reduce climate change. The project work presents the concept of an urban solution where the former Arrigoni factory was located in Izola. In the currently degraded area, the fishing spirit of the town, which it used to be, is being re-established ruled in Izola. In the considered area I place the production of activities for the production of fish products and wines. With this, in addition to the city's identity, I provide new jobs and interesting things in the space tourist spot. With a mix of production, business and central activities and open public the premises are provided with mixed use intended for different users of the premises. When designing a new arrangement in the room, I take into account the guidelines for reducing the creation urban heat islands, which negatively affect the quality of life in the area and the climate changes.

Magnetic extraction offers a rapid and low-cost solution to microplastic (MP) separation, in which we magnetize the hydrophobic surface of MPs to separate them from complex environmental matrices using magnets. We synthesized a hydrophobic Fe-silane based nanocomposite (Fe@SiO2/MDOS) to separate MPs from freshwater. Pristine and weathered, polyethylene (PE) and tire wear particles (TWP) of different sizes were used in the study. The weathering of MPs was performed in an accelerated weathering chamber according to ISO 4892-2:2013 standards that mimic natural weathering conditions. The chemical properties and morphology of the Fe@SiO2/MDOS, PE and TWP were confirmed by Fourier transform infrared spectroscopy and Scanning electron microscopy, respectively. The thermal properties of PE and TWP were evaluated by Thermogravimetric analysis. Using 1.00 mg of Fe@SiO2/MDOS nanocomposite, 2.00 mg of pristine and weathered PE were extracted from freshwater; whereas, using the same amount of the nanocomposite, 7.92 mg of pristine TWP and 6.87 mg of weathered TWP were extracted. The retrieval of weathered TWP was 13% less than that of pristine TWP, which can be attributed to the increasing hydrophilicity of weathered TWP. The results reveal that the effectiveness of the magnetic separation technique varies among different polymer types and their sizes; the weathering of MPs also influences the magnetic separation efficiency. Nasl. z nasl. zaslona. Opis vira z dne 10. 1. 2023. Št. članka: 5189. Bibliografija: str. 13-15. Abstract.

Cilj ove disertacije je ispitivanje katalitičkog potencijala različitih industrijskih, otpadnih ostataka (sojine ljuspice, papirni mulj, crveni mulj i filterski pesak) u heterogenom Fenton-procesu uklanjanja boje. Izvršene su dve vrste modifikacije početnih materijala, u zavisnosti od strukture i inicijalnog sadržaja Fe, i toimpregnacija jonima Fe(III) i termički tretman. Sprovedena je detaljna karakterizacija početnih materijala i pripremljenih katalizatora, zatim su određeni optimalni uslovi heterogene Fentonove reakcije primenom metode odzivnih površina, kao i evaluacija degradacije model polutanta (Reactive Blue 4 boje). Ultrazvukom potpomognuta impregnacija otpadnih sojinih ljuspica i papirnog mulja je doprinela inkorporaciji Fe u strukturu nosača, a kalcinacija katalizatora pri temepraturi od 350°C je dovela do degradacije prisutne celuloze kod oba materijala. Stoga, hemijska modifikacija je rezultovala katalizatorima povećane specifične površine, mezoporoznosti i konvertovanih jona Fe u kristale hematita. NJihovom primenom u oksidacionom procesu primećen je porast efikasnosti obezbojavanja (85,7 i 96,7%, redom), dok je ~66% RB4 boje mineralizovano. Stabilnost ovih katalizatora je bila na zadovoljavajućem nivou, gde je papirni mulj izdvojen kao superioran predstavnik stabilnog katalizatora u kiseloj sredini (izluženo je svega 0,002 mg Fe/l). Niska toksičnost efluenta (~20%) je ispitana kroz test inhibicije rasta Vibrio fischeri bakterija. Takođe, ponovna upotreba impregnisanih otpadnih ostataka ukazala je na blago smanjenje aktivnosti (~11%), što se može sanirati regeneracijom katalizatora. Otpadni crveni mulj i filterski pesak su termički tretirani (550°C) zbog poznatog prisutsva Fe na njihovim površinama. Karakterizacijom je primećena značajna razlika među njima, gde je crveni mulj bio sačinjen od sitnih, mezoporoznih čestica, sa kristalima hematita, a filterski pesak je imao krupniju granulaciju i značajno viši sadržaj Mn u odnosu na Fe što je verovatno uslovilo njegovu semi-kristalnu strukturu. Među njima, otpadni crveni mulj se pokazao aktivnim u heterogenom Fenton-procesu, sa efikasnošću obezbojavanja od 90,1%, i stabilnim u pogledu izluženog Fe (0,22 mg/l). Međutim, primećeno je i prisustvo Al u koncentracijama bliskim dozvoljenim graničnim vrednostima (~3 mg/l), što je verovatno doprinelo povišenoj inhibiciji rasta Vibrio fischeri bakterija (~35%). Sa druge strane, primenom otpadnog filterskog peska u oksidacionom tretmanu postignuto je umereno obezbojavanje vodenog rastvora RB4 boje, uz znatno više izluživanje Fe i dodatnog Mn u vodenu fazu. Dato sekundarno zagađenje je doprinelo izraženoj toksičnosti efluenta (73%), te se ne predlaže njegova dalja primena u Fenton-procesu. Pored odabranih otpadnih ostataka, ispitana je i modifikacija i primena komercijalno dostupnih materijala – Na-bentonita i Fe(III)-oksida. Smektitna glina je impregnisana jonima Fe(III), gde se pokazalastabilnom tokom kalcinacije. Pripremljen mezoporozni katalizator je bio veoma aktivan u degradaciji RB4 boje (94,0%) uz nisko izluživanje Fe, gde je udeo sorpcije bio ~10%. Sa druge strane, Fe2O3 je pokazao nezavidnu aktivnost ispod 20%), što je verovatno prouzrokovano veoma niskom specifičnom površinom (najmanja među svim ispitivanim katalizatorima). Na osnovu rezultata ove disertacije, izdvajaju se otpadni papirni i crveni mulj kao dva predstavnika aktivnih katalizatora heterogene Fentonove reakcije. Otpadni papirni mulj nakon ultrazvukom unapređene impregnacije je veoma stabilan katalizator, a njegova aktivnost je potpomognuta i simultanim odvijanjem sorpcionih reakcija. Crveni mulj, takođe, ima potencijal za primenu u oksidacionom tretmanu, s tim što je neophodno praćenje stabilnosti, uz poseban osvrt na izluživanje Al, ali i ostalih prisutnih elemenata u njegovoj strukturi. Tako bi se obezbedilo bezbedno i efikasno iskorišćenje industrijskog otpada., The aim of this dissertation is to investigate the catalytic potential of various industrial waste residues (soybean hulls, paper mill sludge, red mud and filter sand) in the heterogeneous Fenton process of dye removal. Two types of modification of the initial materials were performed, depending on the structure and initial Fe content, namely impregnation with Fe (III) ions and thermal treatment. Detailed characterization of waste residues and prepared catalysts was performed, then the optimal conditions ofthe heterogeneous Fenton reaction were determined using the response surface methodology, as well as the evaluation of model pollutant (Reactive Blue 4 dye) degradation. Ultrasound assisted impregnation of waste soybean hulls and paper mill sludge contributed to the incorporation of Fe into the carrier structure, and the calcination of catalysts at 350°C led to the degradation of cellulose present in both materials. Therefore, the chemical modification resulted in catalysts with increased specific surface area, mesoporosity and converted Fe ions to hematite crystals. Their application in the oxidation process showed an increase in decolorization efficiency (85.7 and 96.7%, respectively), while ~66% of RB4 dye was mineralized. The stability of these catalysts was at a satisfactory level, where paper sludge was isolated as a superior representative of a stable catalyst in an acidic medium (only 0.002 mg Fe/L was leached). The toxicity of the effluent was also examined, through the test of Vibrio fischeri bacteria growth inhibition, which was low (~20%). Also, the reuse of impregnated waste residues indicated a slight decrease in activity (~ 11%), which can be remedied by catalyst regeneration. Waste red mud and filter sand were thermally treated (550°C) due to the known presence of Fe on their surfaces. The characterization showed a significant difference between them, where the red mud, was composed of small, mesoporous particles with hematite crystals, while the filter sand had a larger granulation and significantly higher Mn content compared to Fe, which probably conditioned its semi-crystalline structure. Among them, waste red mud proved to be active in the heterogeneous Fenton process, with a decolorization efficiency of 90.1%, and stable in terms of leached Fe (0.22 mg/L). However, the presence of Al was also observed in concentrations close to the permitted limit values (~3 mg/L), which probablycontributed to the increase in the inhibition of Vibrio fischeri bacterial growth (~35%). On the other hand, with application of waste filter sand in the oxidation treatment moderate discoloration of the aqueous solution of RB4 dye was achieved, with significantly higher leaching of Fe and additional Mn into the aqueous phase. The given secondary pollution contributed to the pronounced toxicity of the effluent (73%), and its further application in the Fenton process is not proposed. In addition to selected waste residues, the modification and application of commercially available materials (Na-bentonite and Fe(III)-oxide) were investigated. Smectite clay was impregnated with Fe (III) ions, where it proved to be stable during calcination. The prepared mesoporous catalyst was very active in the degradation of RB4 dye (94.0%) with low Fe leaching, where the sorption fraction was ~10%. On the other hand, Fe2O3 showed unenviable activity (below 20%), which is probably caused by a very low specific surface area (the lowest among all tested catalysts)Based on the results of this dissertation, waste paper mill sludge and red mud are singled out as two representatives of active catalysts for the heterogeneous Fenton reaction. Waste paper mill sludge after ultrasonic impregnation is a very stable catalyst, and its activity is supported by the simultaneous occurrence of sorption reactions. Red mud also has the potential for application in oxidative treatment, but it is necessary to monitor its stability, with special reference to the leaching of Al, and also other elements present in its structure. This would ensure the safe and efficient use of industrial waste.

Cilj ove disertacije je ispitivanje katalitičkog potencijala različitih industrijskih, otpadnih ostataka (sojine ljuspice, papirni mulj, crveni mulj i filterski pesak) u heterogenom Fenton-procesu uklanjanja boje. Izvršene su dve vrste modifikacije početnih materijala, u zavisnosti od strukture i inicijalnog sadržaja Fe, i toimpregnacija jonima Fe(III) i termički tretman. Sprovedena je detaljna karakterizacija početnih materijala i pripremljenih katalizatora, zatim su određeni optimalni uslovi heterogene Fentonove reakcije primenom metode odzivnih površina, kao i evaluacija degradacije model polutanta (Reactive Blue 4 boje). Ultrazvukom potpomognuta impregnacija otpadnih sojinih ljuspica i papirnog mulja je doprinela inkorporaciji Fe u strukturu nosača, a kalcinacija katalizatora pri temepraturi od 350°C je dovela do degradacije prisutne celuloze kod oba materijala. Stoga, hemijska modifikacija je rezultovala katalizatorima povećane specifične površine, mezoporoznosti i konvertovanih jona Fe u kristale hematita. NJihovom primenom u oksidacionom procesu primećen je porast efikasnosti obezbojavanja (85,7 i 96,7%, redom), dok je ~66% RB4 boje mineralizovano. Stabilnost ovih katalizatora je bila na zadovoljavajućem nivou, gde je papirni mulj izdvojen kao superioran predstavnik stabilnog katalizatora u kiseloj sredini (izluženo je svega 0,002 mg Fe/l). Niska toksičnost efluenta (~20%) je ispitana kroz test inhibicije rasta Vibrio fischeri bakterija. Takođe, ponovna upotreba impregnisanih otpadnih ostataka ukazala je na blago smanjenje aktivnosti (~11%), što se može sanirati regeneracijom katalizatora. Otpadni crveni mulj i filterski pesak su termički tretirani (550°C) zbog poznatog prisutsva Fe na njihovim površinama. Karakterizacijom je primećena značajna razlika među njima, gde je crveni mulj bio sačinjen od sitnih, mezoporoznih čestica, sa kristalima hematita, a filterski pesak je imao krupniju granulaciju i značajno viši sadržaj Mn u odnosu na Fe što je verovatno uslovilo njegovu semi-kristalnu strukturu. Među njima, otpadni crveni mulj se pokazao aktivnim u heterogenom Fenton-procesu, sa efikasnošću obezbojavanja od 90,1%, i stabilnim u pogledu izluženog Fe (0,22 mg/l). Međutim, primećeno je i prisustvo Al u koncentracijama bliskim dozvoljenim graničnim vrednostima (~3 mg/l), što je verovatno doprinelo povišenoj inhibiciji rasta Vibrio fischeri bakterija (~35%). Sa druge strane, primenom otpadnog filterskog peska u oksidacionom tretmanu postignuto je umereno obezbojavanje vodenog rastvora RB4 boje, uz znatno više izluživanje Fe i dodatnog Mn u vodenu fazu. Dato sekundarno zagađenje je doprinelo izraženoj toksičnosti efluenta (73%), te se ne predlaže njegova dalja primena u Fenton-procesu. Pored odabranih otpadnih ostataka, ispitana je i modifikacija i primena komercijalno dostupnih materijala – Na-bentonita i Fe(III)-oksida. Smektitna glina je impregnisana jonima Fe(III), gde se pokazalastabilnom tokom kalcinacije. Pripremljen mezoporozni katalizator je bio veoma aktivan u degradaciji RB4 boje (94,0%) uz nisko izluživanje Fe, gde je udeo sorpcije bio ~10%. Sa druge strane, Fe2O3 je pokazao nezavidnu aktivnost ispod 20%), što je verovatno prouzrokovano veoma niskom specifičnom površinom (najmanja među svim ispitivanim katalizatorima). Na osnovu rezultata ove disertacije, izdvajaju se otpadni papirni i crveni mulj kao dva predstavnika aktivnih katalizatora heterogene Fentonove reakcije. Otpadni papirni mulj nakon ultrazvukom unapređene impregnacije je veoma stabilan katalizator, a njegova aktivnost je potpomognuta i simultanim odvijanjem sorpcionih reakcija. Crveni mulj, takođe, ima potencijal za primenu u oksidacionom tretmanu, s tim što je neophodno praćenje stabilnosti, uz poseban osvrt na izluživanje Al, ali i ostalih prisutnih elemenata u njegovoj strukturi. Tako bi se obezbedilo bezbedno i efikasno iskorišćenje industrijskog otpada. The aim of this dissertation is to investigate the catalytic potential of various industrial waste residues (soybean hulls, paper mill sludge, red mud and filter sand) in the heterogeneous Fenton process of dye removal. Two types of modification of the initial materials were performed, depending on the structure and initial Fe content, namely impregnation with Fe (III) ions and thermal treatment. Detailed characterization of waste residues and prepared catalysts was performed, then the optimal conditions ofthe heterogeneous Fenton reaction were determined using the response surface methodology, as well as the evaluation of model pollutant (Reactive Blue 4 dye) degradation. Ultrasound assisted impregnation of waste soybean hulls and paper mill sludge contributed to the incorporation of Fe into the carrier structure, and the calcination of catalysts at 350°C led to the degradation of cellulose present in both materials. Therefore, the chemical modification resulted in catalysts with increased specific surface area, mesoporosity and converted Fe ions to hematite crystals. Their application in the oxidation process showed an increase in decolorization efficiency (85.7 and 96.7%, respectively), while ~66% of RB4 dye was mineralized. The stability of these catalysts was at a satisfactory level, where paper sludge was isolated as a superior representative of a stable catalyst in an acidic medium (only 0.002 mg Fe/L was leached). The toxicity of the effluent was also examined, through the test of Vibrio fischeri bacteria growth inhibition, which was low (~20%). Also, the reuse of impregnated waste residues indicated a slight decrease in activity (~ 11%), which can be remedied by catalyst regeneration. Waste red mud and filter sand were thermally treated (550°C) due to the known presence of Fe on their surfaces. The characterization showed a significant difference between them, where the red mud, was composed of small, mesoporous particles with hematite crystals, while the filter sand had a larger granulation and significantly higher Mn content compared to Fe, which probably conditioned its semi-crystalline structure. Among them, waste red mud proved to be active in the heterogeneous Fenton process, with a decolorization efficiency of 90.1%, and stable in terms of leached Fe (0.22 mg/L). However, the presence of Al was also observed in concentrations close to the permitted limit values (~3 mg/L), which probablycontributed to the increase in the inhibition of Vibrio fischeri bacterial growth (~35%). On the other hand, with application of waste filter sand in the oxidation treatment moderate discoloration of the aqueous solution of RB4 dye was achieved, with significantly higher leaching of Fe and additional Mn into the aqueous phase. The given secondary pollution contributed to the pronounced toxicity of the effluent (73%), and its further application in the Fenton process is not proposed. In addition to selected waste residues, the modification and application of commercially available materials (Na-bentonite and Fe(III)-oxide) were investigated. Smectite clay was impregnated with Fe (III) ions, where it proved to be stable during calcination. The prepared mesoporous catalyst was very active in the degradation of RB4 dye (94.0%) with low Fe leaching, where the sorption fraction was ~10%. On the other hand, Fe2O3 showed unenviable activity (below 20%), which is probably caused by a very low specific surface area (the lowest among all tested catalysts)Based on the results of this dissertation, waste paper mill sludge and red mud are singled out as two representatives of active catalysts for the heterogeneous Fenton reaction. Waste paper mill sludge after ultrasonic impregnation is a very stable catalyst, and its activity is supported by the simultaneous occurrence of sorption reactions. Red mud also has the potential for application in oxidative treatment, but it is necessary to monitor its stability, with special reference to the leaching of Al, and also other elements present in its structure. This would ensure the safe and efficient use of industrial waste.

Cilj ove disertacije je ispitivanje katalitičkog potencijala različitih industrijskih, otpadnih ostataka (sojine ljuspice, papirni mulj, crveni mulj i filterski pesak) u heterogenom Fenton-procesu uklanjanja boje. Izvršene su dve vrste modifikacije početnih materijala, u zavisnosti od strukture i inicijalnog sadržaja Fe, i toimpregnacija jonima Fe(III) i termički tretman. Sprovedena je detaljna karakterizacija početnih materijala i pripremljenih katalizatora, zatim su određeni optimalni uslovi heterogene Fentonove reakcije primenom metode odzivnih površina, kao i evaluacija degradacije model polutanta (Reactive Blue 4 boje). Ultrazvukom potpomognuta impregnacija otpadnih sojinih ljuspica i papirnog mulja je doprinela inkorporaciji Fe u strukturu nosača, a kalcinacija katalizatora pri temepraturi od 350°C je dovela do degradacije prisutne celuloze kod oba materijala. Stoga, hemijska modifikacija je rezultovala katalizatorima povećane specifične površine, mezoporoznosti i konvertovanih jona Fe u kristale hematita. NJihovom primenom u oksidacionom procesu primećen je porast efikasnosti obezbojavanja (85,7 i 96,7%, redom), dok je ~66% RB4 boje mineralizovano. Stabilnost ovih katalizatora je bila na zadovoljavajućem nivou, gde je papirni mulj izdvojen kao superioran predstavnik stabilnog katalizatora u kiseloj sredini (izluženo je svega 0,002 mg Fe/l). Niska toksičnost efluenta (~20%) je ispitana kroz test inhibicije rasta Vibrio fischeri bakterija. Takođe, ponovna upotreba impregnisanih otpadnih ostataka ukazala je na blago smanjenje aktivnosti (~11%), što se može sanirati regeneracijom katalizatora. Otpadni crveni mulj i filterski pesak su termički tretirani (550°C) zbog poznatog prisutsva Fe na njihovim površinama. Karakterizacijom je primećena značajna razlika među njima, gde je crveni mulj bio sačinjen od sitnih, mezoporoznih čestica, sa kristalima hematita, a filterski pesak je imao krupniju granulaciju i značajno viši sadržaj Mn u odnosu na Fe što je verovatno uslovilo njegovu semi-kristalnu strukturu. Među njima, otpadni crveni mulj se pokazao aktivnim u heterogenom Fenton-procesu, sa efikasnošću obezbojavanja od 90,1%, i stabilnim u pogledu izluženog Fe (0,22 mg/l). Međutim, primećeno je i prisustvo Al u koncentracijama bliskim dozvoljenim graničnim vrednostima (~3 mg/l), što je verovatno doprinelo povišenoj inhibiciji rasta Vibrio fischeri bakterija (~35%). Sa druge strane, primenom otpadnog filterskog peska u oksidacionom tretmanu postignuto je umereno obezbojavanje vodenog rastvora RB4 boje, uz znatno više izluživanje Fe i dodatnog Mn u vodenu fazu. Dato sekundarno zagađenje je doprinelo izraženoj toksičnosti efluenta (73%), te se ne predlaže njegova dalja primena u Fenton-procesu. Pored odabranih otpadnih ostataka, ispitana je i modifikacija i primena komercijalno dostupnih materijala – Na-bentonita i Fe(III)-oksida. Smektitna glina je impregnisana jonima Fe(III), gde se pokazalastabilnom tokom kalcinacije. Pripremljen mezoporozni katalizator je bio veoma aktivan u degradaciji RB4 boje (94,0%) uz nisko izluživanje Fe, gde je udeo sorpcije bio ~10%. Sa druge strane, Fe2O3 je pokazao nezavidnu aktivnost ispod 20%), što je verovatno prouzrokovano veoma niskom specifičnom površinom (najmanja među svim ispitivanim katalizatorima). Na osnovu rezultata ove disertacije, izdvajaju se otpadni papirni i crveni mulj kao dva predstavnika aktivnih katalizatora heterogene Fentonove reakcije. Otpadni papirni mulj nakon ultrazvukom unapređene impregnacije je veoma stabilan katalizator, a njegova aktivnost je potpomognuta i simultanim odvijanjem sorpcionih reakcija. Crveni mulj, takođe, ima potencijal za primenu u oksidacionom tretmanu, s tim što je neophodno praćenje stabilnosti, uz poseban osvrt na izluživanje Al, ali i ostalih prisutnih elemenata u njegovoj strukturi. Tako bi se obezbedilo bezbedno i efikasno iskorišćenje industrijskog otpada., The aim of this dissertation is to investigate the catalytic potential of various industrial waste residues (soybean hulls, paper mill sludge, red mud and filter sand) in the heterogeneous Fenton process of dye removal. Two types of modification of the initial materials were performed, depending on the structure and initial Fe content, namely impregnation with Fe (III) ions and thermal treatment. Detailed characterization of waste residues and prepared catalysts was performed, then the optimal conditions ofthe heterogeneous Fenton reaction were determined using the response surface methodology, as well as the evaluation of model pollutant (Reactive Blue 4 dye) degradation. Ultrasound assisted impregnation of waste soybean hulls and paper mill sludge contributed to the incorporation of Fe into the carrier structure, and the calcination of catalysts at 350°C led to the degradation of cellulose present in both materials. Therefore, the chemical modification resulted in catalysts with increased specific surface area, mesoporosity and converted Fe ions to hematite crystals. Their application in the oxidation process showed an increase in decolorization efficiency (85.7 and 96.7%, respectively), while ~66% of RB4 dye was mineralized. The stability of these catalysts was at a satisfactory level, where paper sludge was isolated as a superior representative of a stable catalyst in an acidic medium (only 0.002 mg Fe/L was leached). The toxicity of the effluent was also examined, through the test of Vibrio fischeri bacteria growth inhibition, which was low (~20%). Also, the reuse of impregnated waste residues indicated a slight decrease in activity (~ 11%), which can be remedied by catalyst regeneration. Waste red mud and filter sand were thermally treated (550°C) due to the known presence of Fe on their surfaces. The characterization showed a significant difference between them, where the red mud, was composed of small, mesoporous particles with hematite crystals, while the filter sand had a larger granulation and significantly higher Mn content compared to Fe, which probably conditioned its semi-crystalline structure. Among them, waste red mud proved to be active in the heterogeneous Fenton process, with a decolorization efficiency of 90.1%, and stable in terms of leached Fe (0.22 mg/L). However, the presence of Al was also observed in concentrations close to the permitted limit values (~3 mg/L), which probablycontributed to the increase in the inhibition of Vibrio fischeri bacterial growth (~35%). On the other hand, with application of waste filter sand in the oxidation treatment moderate discoloration of the aqueous solution of RB4 dye was achieved, with significantly higher leaching of Fe and additional Mn into the aqueous phase. The given secondary pollution contributed to the pronounced toxicity of the effluent (73%), and its further application in the Fenton process is not proposed. In addition to selected waste residues, the modification and application of commercially available materials (Na-bentonite and Fe(III)-oxide) were investigated. Smectite clay was impregnated with Fe (III) ions, where it proved to be stable during calcination. The prepared mesoporous catalyst was very active in the degradation of RB4 dye (94.0%) with low Fe leaching, where the sorption fraction was ~10%. On the other hand, Fe2O3 showed unenviable activity (below 20%), which is probably caused by a very low specific surface area (the lowest among all tested catalysts)Based on the results of this dissertation, waste paper mill sludge and red mud are singled out as two representatives of active catalysts for the heterogeneous Fenton reaction. Waste paper mill sludge after ultrasonic impregnation is a very stable catalyst, and its activity is supported by the simultaneous occurrence of sorption reactions. Red mud also has the potential for application in oxidative treatment, but it is necessary to monitor its stability, with special reference to the leaching of Al, and also other elements present in its structure. This would ensure the safe and efficient use of industrial waste.

Two-beam laser welding (TBLW) is an advanced process for precise, low distortion joining of cylindrical miniature parts. The process is composed of a laser source, optics and various actuators, which form a sophisticated system for control and maintenance in high volume manufacturing. A well-established method for identifying welding defects and ensuring welding quality is the monitoring of plasma light emission in TBLW. Although such monitoring systems can detect a change in process status, they are not able to diagnose the nature of the fault. The main challenge in this research was to extend the use of quality-based monitoring systems to measure additional deterioration-related parameters and to estimate system deterioration from them by using expert knowledge. This paper shows a novel condition-based maintenance (CBM) for the TBLW system, which performs condition identification using online monitoring of plasma light emission in combination with offline inspection of the seam macrographs. A combination of quality parameters derived from seam macrographs of defective parts is used to identify process deterioration, such as contamination of the optics, misalignment of the optomechanical system, or reduced laser power. The information obtained is used to make predefined process adjustments based on expert domain knowledge. The implementation of the developed CBM in high volume manufacturing of piezoelectric pressure sensors resulted in more predictable TBLW by reducing system failures as well as shorter diagnosis times.

Operators of photovoltaic (PV) systems, especially the small ones, monitor only the produced energy output, since they are not equipped with a meteorological station, or there is none in the neighbourhood. When evaluating a large number of PV systems across a region or country, access to the data due to privacy restrictions is usually very limited. To resolve both aspects, we report on a methodology to evaluate the performance of photovoltaic systems where only produced energy data and rated power of the PV system are available and all other data, including orientation and inclination angles, and the exact location are missing. We developed a novel algorithm for automatic detection of orientation/inclination angles and used the recently developed Typical Daily Profiles (TDP) methodology for a fast and accurate evaluation of PV systems. TDPs are representative hourly profiles of the observed parameter (e.g., power, irradiance and temperature) on a monthly basis. For the PV system degradation rate extraction, year-to-year TDPs are used. The case study of 957 PV systems in Slovenia in the period 2015–2019 reveals an average PV system performance ratio exceeding 85% and an average PV system rated power degradation rate of −0.7% per year.

The aim of the present study was to investigate how individual phenolic compounds and phenolic groups in walnut husk gratings (e.g., naphthoquinones, flavanols, flavonols, hydroxycinnamic acids) are oxidized over time, with a particular focus on the juglone synthase pathway. Walnut husk gratings were prepared and left under ‘degradation’ conditions (exposure to the air, room temperature) at increasing times. Following methanol extraction of these husk gratings, the HPLC profile of methanolic extract of husk gratings exhibited twenty-six compounds over time, then hydrojuglone glucoside, α-hydrojuglone, and juglone were detailed by HPLC-mass spectrometry. Initially (0–20 min), the content of hydrojuglone glucoside in the husk gratings decreased by 40.4%, while the content of α-hydrojuglone increased by 20.0%, and then decreased. After an initial delay (0–20 min), juglone increased by 47.9% from 20 to 40 min, and then decreased. This initially confirmed that hydrojuglone glucoside and α-hydrojuglone could be considered as precursors of juglone. Different phenolic groups showed different degradation processes, although they all reached their highest content after 40 min. This might arise from degradation of the phenols, increased free phenols, or activation of the plant defense mechanism due to damage to the tissue, similar to the effects of stress or a pathogen attack. Although it has been reported that the phenolic compounds decrease when food is processed or damaged, they showed increases, which were not indefinite, but time dependent. As phenolic compounds are considered highly beneficial to human health, increases upon processing indicate the need for further investigations into healthier food preparation processes. This is the first study on the degradation pathways of juglone, using a mass spectrometer, in which we suggest that hydrojuglone glucoside and α-hydrojuglone are indeed the precursors of juglone. However, it is possible that there are other degradation pathways of hydrojuglone glucoside, since less juglone is synthesized than expected.

Poljoprivreda štetno djeluje na okoliš, u istom intenzitetu kao i uporaba fosilnih goriva. To je potvrđeno i u Izvješću UN-a iz 2010., koje je izrađeno povodom Svjetskog dana zaštite okoliša. Pri ulasku Republike Hrvatske u EU, preuzete su i pravne stečevine EU u nacionalno zakonodavstvo na području okoliša. Republika Hrvatska preuzela je i obvezu ispunjavanja standarda zaštite okoliša sustavom izdavanja dozvola za sva postrojenja na koja se primjenjuje Direktiva 96/61/EC o integriranom sprječavanju i kontroli onečišćenja (IPPC Direktiva). Poljoprivreda snažno utječe na okoliš u smislu potencijalnih onečišćenja tla i voda, te doprinosi globalnom zagrijavanju zbog emisije stakleničkih plinova. Globalno gledajući, zbog rastućih potreba za proizvodnjom hrane, šire se poljoprivredne površine, intenzivira proizvodnja, povećava se uporaba sredstava za zaštitu, a sve to neizbježno dovodi do povećanog opterećenja okoliša (Voća, 2012.). Intenzivna eksploatacija tla uz neizbježnu uporabu mehanizacije pospješuje degradaciju tla, što ima višestruke i složene učinke na globalno okruženje kroz niz izravnih i neizravnih procesa, koji utječu na veliki broj funkcija i usluga ekosustava. Posljedice degradacije očituju se kroz: gubitak organske tvari, smanjenje plodnosti tla, smanjenje biološke raznolikosti, kvalitete zraka i vode, onečišćenje, prekrivanje i prenamjenu tla te klimatske promjene. Destrukcija tla u vidu prekomjernog sabijanja, te pojedini procesi degradacije tla imaju prirodne uzroke, ali se njihovo napredovanje višestruko ubrzava antropogenim utjecajem.

Tokom protekle decenije došlo je do velikog naučnog i javnog interesovanja za uticaj plastike na životnu sredinu, žive organizme, uključujući ljude i živi svet u morskim ekosistemima. Procenjuje se da je loše upravljanje otpadom dovelo do ispuštanja do 23 miliona tona plastike u okean na godišnjem nivou (Borrelle i sar., 2020). Plastični ostaci u životnoj sredini se u prirodi razgrađuju foto-, bio- i termo-oksidativnom depolimerizacijom, kao i trenjem. Iako je biorazgradnja ove plastike izvodljiva u prirodnom okruženju, ona može trajati od 50 do više od 100 godina (Barnes i sar., 2009). Istraživanje zagađenja životne sredine sintetičkim polimerima i njihov efekat na prirodu je istraživačka disciplina koja se brzo razvija. Izdvajanje plastičnih čestica iz uzorka radi njihove detekcije i dalje karakterizacije predstavlja veliki izazov jer su često pomešne sa velikim količinama mineralnih i biogenih organskih supstanci. Izolovanje plastičnih čestica zahteva uklanjanje prirodnog matriksa uzorka. Optimalna metoda digestije bi morala da eliminiše biogene organske materije, ali da očuva integritet čestice sintetičkog polimera. U tu svrhu primenjuju se hemijske digestije kiselinama, bazama, oksidansima i enzimima. Brojne studije bave se poređenjem različitih metoda digestije radi provere efikasnosti uklanjanja biogenih organskih materija. Primenjeni protokoli treba da ostave intakne sintetičke polimere prvenstveno u pogledu njihove hemijske strukture, a zatim i u pogledu njihove težine, zapremine, oblika i, ako je potrebno, boje. Očuvanje hemijske strukture ili površinske strukture i morfologije polimera u velikoj meri zavisi od odabira adekvatne metode digestije (Enders i sar., 2017). Efikasnost razaranja biogenih organskih materija zavisi od matriksa. Na primer, primena jakih kiselina, kao što je azotna kiselina (HNO3) pokazuje dobre rezultate kada se koristi za digestiju bioloških tkiva, koje se uglavnom sastoji od proteina, ugljenih hidrata i masti (Nuelle i sar., 2014). Validacijia protokola digestije je neophodna i ogleda se u korišćenju analitičkih i instrumentalnih metoda kako bi se pouzdano i nedvosmisleno dobili podaci o izolovanoj plastici. Neophodna su dalja istraživanja i detaljne analize, koje sve češće uključuju spektroskopske analize primenom Raman ili FTIR-spektroskopije.

Sugar beet (Beta vulgaris var. saccharifera L.) is a profitable industrial crop, but also one of the most demanding, considering the production technology and the growing period of almost 180 days. Sugar beet is attacked by numerous pests such as wireworms, sugar beet flea beetles, aphids, and others, which significantly reduce yield, root quality and sugar content. In the last 20 years, sugar beet protection has been successfully carried out using the method of seed treatment with neonicotinoids (imidacloprid and thiamethoxam). Because they are suspected of having negative effects on bee colonies and other beneficial organisms, the EC regulation prohibits their use starting in 2019, except in permanent greenhouses or with special permission. Among the most important beneficial soil fauna of sugar beets are ground beetles and earthworms, which have an indirect positive impact on the crop by increasing soil fertility, regulating the water-air ratio or reducing the number of pests. Due to the ban on neonicotinoids, sugar beet production has halved compared to previous years, amounting to only 10,000 hectares. The environmental assessment of plant protection products for soil organisms is mainly based on the results of laboratory and extended laboratory studies, while the link from the laboratory to realistic field conditions over several seasons is not well established. Despite the ban, the degradation dynamics of neonicotinoids in plants sown from treated seeds and their effects on these plants and the surrounding soil are still not well understood. Moreover, the residues of neonicotinoids and their bioaccumulation in beneficial soil fauna in Croatia have not yet been determined, nor has their impact on the numbers and composition of these organisms. Therefore, the objectives of this research were: (i) to determine the efficacy of neonicotinoids on the main pests and the degradation dynamics in sugar beet plants grown from seeds treated with imidacloprid and thiamethoxam under different weather conditions; (ii) determine the residues of neonicotinoids in ground beetles, earthworms, and soil of sugar beet fields; and (iii) determine the cenological composition of ground beetles and the possibility of population recovery in sugar beet fields and fields included in a four-year crop rotation. Monitoring of neonicotinoid efficacy against major pests and degradation dynamics was conducted over two years (2015 and 2016) in Virovitica - Podravina (Lukač) and Vukovar - Syrmium (Tovarnik) counties and under laboratory conditions. Samples were collected using standard protocols, including pitfall traps for ground beetles and ISO - ISO 23611-1:2006 methodology for earthworm sampling. Residue analysis was performed using the LC-MS / MS SPE - QuEChERS method with LOQ of 0.01 mg/kg for plant and soil samples and 0.001 mg/kg for animal samples. A biocenological-synecological analysis of ground beetles was performed to determine the ecological indices of the population, and based on the calculated dominance, the represented species were classified according to Tischler and Haydeman. Collected samples were determined to species using standard identification keys. Results were statistically analyzed using ANOVA. Results show that insecticide treatment of sugar beet seed leaves minimal residues in plants and is completely degraded by the end of the growing season. Elevated concentrations of residues in the soil indicate that in dry climates or after a dry period, there is a risk to crops that follow sugar beets in the rotation. All neonicotinoid residues detected in beneficial organisms were below levels considered lethal throughout the sampling period, so it can be assumed that insecticides do not accumulate in these organisms. Calculation of the bioconcentration factor using the retrospective analysis method of analytically measured neonicotinoid residues in the samples indicates that there is no risk to earthworms and no potential for secondary poisoning in birds and mammals that feed on them. The composition and abundance of ground beetles in sugar beet fields is strongly influenced by several factors during the growing season, with insecticides having negative effects, while reduced tillage, lower temperatures, and more rainfall lead to higher ground beetle abundance and diversity. Growing sugar beets in a four-year rotation provides a recovery in the ground beetle population. The research also resulted in a comprehensive list of 64 ground beetle determined to species in maize, sugar beets, wheat, and soybeans, and represents a valuable finding that complements previous studies in Croatia. A better understanding of ground beetles in intensive agricultural landscapes is a good starting point for conservation programs that have become standard in the European Union. S obzirom na tehnologiju proizvodnje i duljinu vegetacije od gotovo 180 dana, šećerna repa smatra se najzahtjevnijom poljoprivrednom kulturom (Pospišil, 2013; Kristek, 2015). Tijekom vegetacije izložena je napadu brojnih štetnika koji smanjuju prinos, kvalitetu korijena i sadržaj šećera. Tehnologija proizvodnje šećerne repe obuhvaća velik broj zahvata te intenzivno suzbijanja korova i štetnika, što negativno djeluje na korisne organizme u tlu (Bažok i sur., 2015). Zaštita šećerne repe od štetnih kukaca posljednjih se dvadesetak godina učinkovito provodila tretiranjem sjemena insekticidima iz skupine neonikotinoida u slučaju žičnjaka, buhača i lisnih uši (Dobrinčić, 2002; Bažok, 2010). Folijarna primjena insekticida usmjerena je na suzbijanje repine pipe (Bažok i sur., 2012). Prema Castle i sur. (2005) te Byrne i Toscano (2006), koncentracija imidakloprida između 0,005 i 0,01 mg/kg u biljnom tkivu osigurava učinkovitu zaštitu od štetnika, što se postiže upravo tretmanom sjemena. Iako su od sredine 1990-ih do danas neonikotinoidi bili najčešće korišteni insekticidi na svijetu, zbog sumnje na negativan utjecaj na pčelinje zajednice, Uredbom Europske komisije (EU) 485/2013 zabranjeno je korištenje tiametoksama, imidakloprida i klotianidina na većini ratarskih kultura. Zabrana nije obuhvaćala šećernu repu jer nije smatrana atraktivnom pčelama. Konačna odluka o zabrani donesena je 27. travnja 2018. (Bažok i Lemić, 2018), a temeljila se na svim relevantnim istraživanjima diljem svijeta (EFSA, 2018a, 2018b, 2018c). Odluka se počela primjenjivati od 2019. u većini država članica EU-a. Iako su neonikotinoidi danas zabranjeni u Europi i Ujedinjenom Kraljevstvu, još se uvijek uz posebne dozvole mogu koristiti za zaštitu pojedinih usjeva (Harrison-Dunn, 2021). Uklanjanjem neonikotinoida iz primjene istodobno se povećala primjena drugih insekticida, najčešće piretroida (Kathage i sur., 2017). Osim štetnika, u šećernoj repi javljaju se i brojni pripadnici korisne faune s neizravno pozitivnim utjecajem na kultivirane biljke. Najvažnija korisna fauna tla šećerne repe uključuje kukce, osobito red Carabidae, odnosno trčke (Kos i Bažok, 2015), i gujavice (Pisa i sur., 2014). Zbog velike brojnosti, poznate taksonomije i osjetljivosti na promjene uzrokovane vanjskim čimbenicima trčci se često koriste u ekološkim istraživanjima (Lövei i Sunderland, 1996). Smanjenje populacije trčaka na nekom području posljedica je većeg unosa agrokemikalija, gubitka travnih pojaseva za ishranu i povećavanja veličine parcela (Fahrig i sur., 2015). Sastav faune trčaka te dinamika njihove pojave u Hrvatskoj nisu poznati iako se često navodi da su insekticidi glavni čimbenik smanjenja njihove brojnosti. Gujavice ili humifikatori važni su članovi faune tla (Luo i sur., 1999). Sudjeluju u fragmentaciji, razgradnji i inkorporaciji organske tvari (Edwards i Bohlen, 1996). U poljoprivrednim tlima čine do 80 % ukupne životinjske biomase (Luo i sur., 1999). Sredstva za zaštitu bilja predstavljaju opasnost za preživljavanje i ponašanje gujavica ometajući razvoj i procese razgradnje tla (Volkov i sur., 2007). Istraživanje se provodilo tijekom dviju godina (2015. i 2016.) u Virovitičko-podravskoj županiji (Lukač) i Vukovarsko-srijemskoj županiji (Tovarnik) te u laboratorijskim uvjetima na Zavodu za poljoprivrednu zoologiju Agronomskog fakulteta Sveučilišta u Zagrebu. Podaci o vremenskim uvjetima prikupljeni su iz Državnog hidrometeorološkog zavoda. Na oba lokaliteta u obje godine šećerna repa bila je posijana na 3,000 m2. Varijante su uključivale netretirano (NT) sjeme šećerne repe, sjeme tretirano imidaklopridom (IMI) i tiametoksamom (TMX). Svaka varijanta bilja zasijana je na 1,000 m2. U laboratorijskim uvjetima sjeme šećerne repe posijano je u supstrat u plastične posude zapremnine 130 l. Osim polja šećerne repe na kojima su zasijani pokusi, na svakom od lokaliteta odabrana su još tri polja na kojima je šećerna repa bila zasijana pred jednu, dvije ili tri godine s ciljem prikupljanja uzoraka faune te kako bi se utvrdili brojnost i sastav faune trčaka i utjecaj intenzivnog uzgoja šećerne repe na navedene organizme. Štetnici i pripadnici korisne faune tla praćeni su i prikupljani standardnim metodama, a za svakog štetnika na temelju frekvencije biljaka u grupama izračunat je postotak (%) štete (Townsend i Heuberger, 1943). Količina rezidua neonikotinoida analizirana je u: (i) biljkama šećerne repe – 432 uzoraka; (ii) trčcima – 14 uzoraka; (iii) gujavicama – 58 uzoraka; (iv) tlu –18 uzoraka. Određivanje rezidua neonikotinoida provedeno je metodom tekućinske kromatografije / tandemskom spektrometrijom mase (LC-MS/MS) nakon ekstrakcije / razdiobe acetonitrilom i čišćenja disperzivnom SPE – QuEChERS metodom (EN 15662:2008). Na istim lokalitetima i poljima prikupljani su uzorci trčaka za cenološku analizu. Prvi set uzoraka trčaka prikupljen je 2015. U epigejskim lovkama prikupljene su 2,582 jedinke, a u endogejskim lovkama 323 jedinke trčaka. Drugi set uzoraka trčaka prikupljen je 2016. s obje lokacije na četiri polja po lokalitetu (četverogodišnji plodored): polje šećerne repe, polje na kojem je repa bila uzgajana godinu dana prije (2015.), dvije godine prije (2014.) i tri godine prije (2013.). Ukupno je prikupljeno 11,763 jedinki trčaka. Svi podaci podvrgnuti su analizi varijance (ANOVA). Rezultati istraživanja učinkovitosti tretiranog sjemena imidaklopridom i tiametoksamom na najvažnije štetnike šećerne repe pokazali su zadovoljavajuću zaštitu od žičnjaka, buhača i repine pipe pri niskom populacijskom pritisku. Gusjenice i lisne uši bile su prisutne u nižoj brojnosti pa se ne može sa sigurnošću utvrditi učinkovitost istraživanih insekticida. Učinkovitost se može očekivati u trajanju od oko sedam tjedana nakon sjetve, što je u skladu s dinamikom razgradnje. Rezultati istraživanja degradacije neonikotinoida u biljkama šećerne repe pokazali su rezidue IMI ispod tolerance (MRL) koja iznosi 0,5 mg/kg 40 – 50 dana nakon sjetve. Analiza razgradnje TMX u polju utvrdila je rezidue ispod MRL (0,02 mg/kg) 70 – 80 dana nakon sjetve. Razgradnja u kontroliranim uvjetima znatno je sporija te su u 2015. rezidue TMX u korijenu repe bile na razini MRL (0,053 mg/kg), dok je iduće godine koncentracija bila ispod MRL u istom vremenu analiziranja. U vrijeme vađenja korijena šećerne repe (180 dana nakon sadnje) rezidue su bile ispod MRL i uvelike su ovisile o vremenskim uvjetima, posebice o količini oborina. Povišena koncentracija rezidua u tlu pokazuje da postoji rizik u suhim klimatskim uvjetima ili nakon sušnog razdoblja, no potrebna su daljnja istraživanja da bi se procijenio mogući unos neonikotinoida u kulture koje dolaze u plodoredu nakon uzgoja šećerne repe iz tretiranog sjemena. Istraživanjem rezidua neonikotinoida u korisnim organizmima utvrđena je koncentracija IMI od 0,027 mg/kg u trčcima, dok su rezidue TMX bile ispod limita kvanitfikacije (LOQ) koji u slučaju životinjskih uzoraka iznosi 0,001 mg/kg. Najviša utvrđena koncentracija IMI u gujavicama iznosila je 0,2141 mg/kg, dok rezidue TMX nisu prelazile 0,0008 mg/kg. Sve utvrđeni rezidue neonikotinoida bile su niže od razina navedenih kao letalnih u cijelom razdoblju uzorkovanja, tako da se može pretpostaviti da ne dolazi do akumulacije insekticida u tim organizmima. Za izračun krivulja razgradnje pesticida u uzorcima gujavica i izmjerene koncentracije u tlu korišteni su parametri razgradnje sredstava za zaštitu bilja (DT50, DT90). Potom su određeni faktori biokoncentracije specifični za spojeve u tlu dijeljenjem analiziranih rezidua pesticida u gujavicama s izračunatim koncentracijama u tlu. Krivulje disipacije na polju (temeljene na EU, EC i EFSA) razumno predviđaju koncentraciju rezidua aktivnih sastojaka u tlu u bilo kojem trenutku nakon primjene. Stoga se analitički utvrđene rezidue u gujavicama s područja Lukača i Tovarika mogu pouzdano koristiti za izračun faktora biokoncentracije. Rezultati su pokazali da primjena istraživanih djelatnih tvari ne predstavlja rizik biokoncentracije za gujavice i nema potencijala sekundarnog trovanja za ptice i sisavce koji se njima hrane. Praćenjem populacije trčaka na istraživanim lokacijama utvrđeni su čimbenici koji utječu na aktivnost i njihovu brojnost. Tijekom 2015. utvrđen je utjecaj specifičnosti okoliša (tip i struktura tla, klimatski uvjeti) zajedno s mjerama uzgoja (obrada tla i primjena insekticida) na aktivnost i brojnost trčaka. S usjeva pšenice na području u Virovitičkopodravske županije determinirano je 26 vrsta i 15 rodova prikupljenih epigejskim (357) i endogejskim lovkama (59). Na navedenom polju šećerna repa bila je uzgajanja prije tri godine Praćenjem dinamike populacije trčaka utvrđeno je da porast populacije prati pad temperature zraka i tla, dok povećanje količine oborina utječe na smanjenje brojnosti trčaka. Tijekom istraživanja 2016. prikupljene su i determinirane 64 vrste trčaka koje pripadaju u 33 roda. U Vukovarsko-srijemskoj županiji u razdoblju od 20 tjedana uzorkovanja prikupljene su ukupno 2,382 jedinke trčaka (25 vrsta) od kojih po brojnosti najviše na poljima šećerne repe (1,131), pšenice (656) i kukuruza (342), a najmanje u soji (253). U Virovitičkopodravskoj županiji prikupljena je ukupno 9,381 jedinka trčaka (56 vrsta), od kojih značajno najviše u kukuruzu (5,656), što još jednom potvrđuje oporavak faune trčaka u višegodišnjem polodoredu. Na istom polju šećerna repa uzgajana je prije četiri godine. U preostalim kulturama utvrđen je broj jedinki kako slijedi: u soji (1,471), šećernoj repi (1,250) i potom pšenici (1,004). Na obje istraživane lokacije karakteristična je eudominantnost pojedinih rodova s velikim brojem pripadnika pojedine vrste. Cenološke analize pokazale su da su sastav i brojnost trčaka u poljima šećerne repe pod jakim utjecajem brojnih čimbenika tijekom vegetacije. Korištenje insekticida nepovoljno utječe na populaciju trčaka, dok smanjena obrada tla, niže temperature i više oborina rezultiraju njihovom većom brojnosti i raznolikosti. Uzgoj šećerne repe u četverogodišnjem plodoredu omogućuje oporavak populacije trčaka. Sveobuhvatan popis od 64 determinirane vrste trčaka iz usjeva kukuruza, šećerne repe, pšenice i soje u Hrvatskoj predstavlja vrijedan nalaz koji nadopunjuje prethodna istraživanja i značajno pridonosi boljem razumijevanju osnovnog stanja populacija trčaka u intenzivnim poljoprivrednim krajobrazima.

Čestice mikroplastike su čestice veličine manje od pet milimetara te predstavljaju jednog od najvećih zagađivača okoliša, naročito morskog. U ovom radu okarakteriziran je sediment Riječkog zaljeva uzorkovan na četiri lokacije duž obale grada Rijeke, od ušća rijeke Rječine do plaže Ploče. Iz sedimenta su izdvojene mikroplastične čestice, koje su razvrstane prema brojnosti, obliku, boji te veličini. Sastav mikroplastičnih analiziran je na FTIR-u (Fourier-transform infrared spectroscopy). Proveden je i eksperiment u svrhu ispitivanja mogućnosti degradacije polimera u reakciji s acetonom, kloroformom, vodenom otopinom KOH te fosfornom kiselinom pri standardnim uvjetima. Navedeni reagensi također su snimani FTIR-om te je usporedbom vibracijskih vrpci određeno je li došlo do promjena koje ukazuju na degradaciju polimera. Microplastic materials include plastic particles smaller than 5 milimeters that represents one of the main pollutants,especially in the marine environment. This thesis provides data of the sediment of Rijeka bay, sampled at 4 locations along the coast of the city of Rijeka, from the mouth of Rječina river to the beach Ploče. Microplastic particles (MP) were separated from the sediment and classified accroding to abundance, shape, color and size. Chemical composition of MP was not determined due to the difficulty of recording tiny particles on FTIR (Fourier-transform infrared spectroscopy). In the second part of the thesis, known types of plastics were treated with 4 reagents-acetone, chloroform, aqueous solution of KOH and phosphoric acid in order to investigate the possibility of polymer degradation in these reagents. Reagents were recorded by FTIR three times at different time intervals. By comparing the vibration bands of the reagents before and after the treatment of the polymer, it was determined that there were no changes, ie no degradation of the treated polymers.

Doktorska disertacija obravnava delovanje in staranje fotonapetostnih (PV) modulov in fotonapetostnih sistemov, ki delujejo v različnih podnebnih razmerah po vsem svetu. Glavni poudarek je na razvoju novih pristopov za ocenjevanje zmogljivosti in izgub modulov in sistemov. Predstavljenih in pojasnjenih je več novih pristopov, ki temeljijo na zajetih podatkih, kot so metoda tipičnih dnevnih profilov (TDP), Köppen-Geiger-Photovoltaic (KGPV) klimatska klasifikacijska shema in ocena donosa zaradi podnebnih sprememb (CCYA). Disertacija obdela metode vrednotenja zmogljivosti in izgub pri proizvodnji električne energije iz fotonapetostnih modulov in sistemov. Pri tem se pridobivajo, združujejo, čistijo in obdelujejo raznolike in velike količine podatkov iz raziskovalnih ustanov, fotovoltaičnih elektrarn, podnebnih modelov in satelitskih podatkov, ki omogočajo dragocen vpogled v dejansko stanje in trende. Podatkovni viri so razvrščeni v geografske informacijske sisteme (GIS) in časovne vrste, pri čemer izkoriščamo oba načina ločeno in skupaj. V okviru disertacije je razvoj pristopov z ustreznim izborom podatkovnih virov, povezanih s fotovoltaiko, omogočil predstavitev globalnih zemljevidov za določitev najboljših področij za proizvodnjo električne energije in opredelitev tveganih lokacij v luči povečane stopnje degradacije, tudi na račun umazanije in zasneževanja. V zadnjem sklopu so ključni kazalniki učinkovitosti, kot sta razmerje učinkovitosti in stopnja degradacije, analizirani, modelirani in ovrednoteni na časovni projekciji do leta 2100 in na globalni prostorski ravni, kar omogoča oceno podnebnih vplivov na podlagi preteklih podatkov in različnih scenarijev podnebnih sprememb. This doctoral dissertation discusses the performance and ageing of PV modules and PV systems operating in different climates worldwide. The primary focus is developing new techniques for assessing the gain and loss factors of PV technologies. Several novel data-driven techniques, such as the Typical Daily Profiles (TDP) method, the Köppen-Geiger-Photovoltaic (KGPV) climate classification scheme, and the Climate Change Yield Assessment (CCYA), are introduced and explained with interesting case studies. The basis of the gain and loss factors of energy production based on typical PV technologies are discussed. Here, diverse and large amounts of data from research facilities, PV power plants, climate models, and satellite-based information are retrieved, combined, cleaned, and processed, bringing valuable insights to the PV industry. The research categorizes data resources into geographical information systems (GIS) and single-time-series, taking advantage of both ways separately and combined. In the frame of this thesis, the selection of relevant PV related data sources and methodologies has allowed the presentation of eye-catching global maps to identify the best places for energy production and the identification of risky locations in terms of degradation, soiling and snow shading. Finally, key performance indicators, such as performance ratio and degradation rates, are analyzed, modelled, and evaluated on a temporal and spatial scale, being able to assess climatic impacts on historical data and under different climate change scenarios.

V diplomskem delu je raziskan vpliv povišanja temperature med procesom strojnega sušenja perila na degradacijo in mečkanje tekstila. Z višanjem temperature sušenja se perilo hitreje posuši, vendar to privede do neželenih posledic, kot je večja emisija tekstilnih vlaken v ozračje, zaradi hitrejše degradacije in večjega mečkanja perila. Poizkusi so bili izvedeni na standardnem sušilnem stroju s toplotno črpalko z maksimalno polnitvijo suhega perila 8 kg, ki je bil modificiran z dodatnim električnim grelnikom. Med rezultati diplomskega dela so prikazane temperature procesnega zraka na vstopu v boben v odvisnosti od časa. Prikazane so tudi mase vlaken, ki so bile ujete na filtru sušilnega stroja, ki dokazujejo, da višanje temperature sušilnega zraka privede do večje degradacije perila. Zadnji del diplomskega dela pa potrjuje zastavljeno hipotezo o odvisnosti mečkanja perila v odvisnosti od temperature. Pri sušenju pri povišani temperaturi se je perilo približno 3-krat bolj mečkalo. This thesis investigates the effect of raising the temperature during the process of machine drying of laundry on the degradation and creasing of textiles. By raising the drying temperature, the time needed to dry laundry is shortened. However, this leads to unwanted results, such as a higher emission of textile fibres into the atmosphere due to the faster degradation and greater creasing of laundry. The experiments were carried out on a standard heat pump dryer with a maximum load of 8 kg of dry laundry, which was modified by adding an electric heater to the process air circuit. The graphs in the results section of this thesis show the changes in temperature in relation to the drying time. The thesis also shows the amount of textile fibres caught on the dryer's filter, which proves that raising the temperature of the drying air leads to greater degradation of textile. The last part of this thesis confirms the hypothesis on the effect of temperature on the creasing of laundry. By drying the laundry at a higher temperature, the textile creased 3 times more than when dried at a lower temperature.

Livade morskih cvjetnica su važni ekosustavi za mnoge druge vrste. U današnje vrijeme prijete im razni čimbenici poput invazivnih vrsta i antropogenog utjecaja. U svrhu izrade ovog rada praćene su tri lokacije na području zapadne Istre u 2020. godini, a to su: uvala Ribnjak, uvala Funtana i uvala Veštar. Na ovim lokacijama su ukupno pronađene četiri livade morskih cvjetnica. Flora na livadama se sastojala od vrsta Cymodocea nodosa i Zostera noltii, a uz cvjetnice su pronađene i određene alge. U uvali Funtana na livadi cvjetnice Cymodocea nodosa uočena je velika kolićina alge Caulerpa cylindracea koja se smatra invazivnom vrstom u Jadranskom moru. Ova se alga smatra invazivnom vrstom jer nije autohtona za naše područje te je otkriveno da je u kompeticijoi za prostor, svjetlost i nutrijente sa našim autohtonim vrstama te da ih polako potiskuje. Upravo ovo se događa sa livadom Cvjetnice Cymodocea nodosa u uvali Funtana koja je radi invazivne alge Caulerpa cylindracea prorijeđena. Osim invazivne vrste, prijetnju predstavljaju i antropogeni čimbenici poput izgradnje i nasipavanja obale, turizma, otpadnih voda itd. Seagrass meadows are important ecosystems for many other species. Nowadays, they are threatened by various factors such as invasive species and anthropogenic impact. For the purpose of preparing this paper, three locations in the area of ​​western Istria in 2020 were monitored, namely: Ribnjak Bay, Funtana Bay and Veštar Bay. A total of four seagrass meadows were found at these locations. The flora in the meadows consisted of the species Cymodocea nodosa and Zostera noltii, and certain algae were found along with the seagrass plants. In the bay of Funtana on the meadow of seagrass Cymodocea nodosa, a large amount of algae Caulerpa cylindracea was observed, which is considered an invasive species in the Adriatic Sea. This algae is considered an invasive species because it is not indigenous to our area and has been found to compete for the space, light and nutrients with our indigenous species and is slowly suppressing them. This is exactly what is happening with the Cymodocea nodosa meadow in Funtana Bay, which has been thinned due to the invasive algae Caulerpa cylindracea. In addition to the invasive species, anthropogenic factors such as coastal construction and embankment, tourism, wastewater, etc. are also a threat.

U sustavima računalnih vida --- bilo da se temelje na obradi videa ili statičkih slika --- česta je pojava degradacija uzrokovana prirodnim elementima. Jedna od takvih degradacija je uzrokovana kišom, koja znatno utječe na moderne sustave zadužene za praćenje objekta u pokretu. Počevši od te problematike, razvija se problem uklanjanja takve degradacije sa jedne slike, koja se ne može oslanjati na vremensku domenu u oklanjanju kišnih anomalija. Ovaj rad detaljno prolazi kroz koncepte i raznovrsne metode uklanjanja kiše sa slike temeljenih na dubokom učenju. Također prolazi kroz implementaciju i rezultate dvije od njih. In modern computer vision systems --- be they based on processing videos or static images --- a common occurrence is degradation of input data by natural elements. One such degradation is caused by rain, which severely impacts systems, such as the ones for motion detection. Using that as a starting point, a sub-domain of problem-solving is developed for removing rain from purely static images, which cannot rely on the existence of a time domain for removing anomalies caused by rain. This work goes into the key concepts and various methods of single-image rain removal, primarily based on deep learning. In addition, it details the implementation and results of two of such methods.

The degradation of the catalyst layer represents one of the main limiting factors in a wider adoption of fuel cells. The identification of the contributions of different mechanisms of catalyst degradation, namely the Ostwald ripening and particle agglomeration, is an important step in the development of mitigation strategies for increasing fuel cell reliability and prolonging its life time. In this paper, the degradation phenomena in high temperature polymer electrolyte membrane fuel cell (HT-PEMFC) are analyzed using a physically-based model of fuel cell operation and catalyst degradation, describing carbon corrosion, platinum dissolution and consequent growth of catalyst particles. The model results indicate significantly different time dependence of catalyst particle growth resulting from different mechanisms: linear growth in the case of particle agglomeration and root-like time dependence for the Ostwald ripening. Based on these results, a new analytic method is proposed, performed by the fitting of a test root-function to the time profile of the particle size growth and using best-fit parameters to identify the prevailing growth mechanism. Using this method on a particle growth time trace deduced from in situ cyclic voltammetry measurement during HT-PEMFC degradation, we are able to identify the agglomeration as the main mechanism of catalyst particle grow.

Protizmrzovalne površine so površine, ki preprečujejo nastajanje ledu. V delu so predstavljene protizmrzovalne površine, ki se uporabljajo pri prenosnikih toplote in metode njihove izdelave. Analizirana je obstojnost različnih superhidrofobnih površin glede na postopek njihove izdelave. Ovrednoteni sta mehanska in kemijska stabilnost superhidrofobnih površin skupaj s trenutnimi omejitvami uporabe in izdelave. Trenutna stopnja razvoja in izdelave še ne omogoča zadostne obstojnosti za pogosto uporabo v realnem življenju. Testi obstojnosti niso standardizirani in ne omogočajo enakovrednega testiranja. Anti-icing surfaces are surfaces that prevent the formation of ice. The paper presents anti-icing surfaces used in heat exchangers and methods of their fabrication. The durability of different superhydrophobic surfaces according to the process of their fabrication is analyzed. The mechanical and chemical stability of superhydrophobic surfaces is evaluated together with the current limitations of use and fabrication. The current stage of development and manufacturing does not yet allow sufficient durability for frequent use in real life. Durability tests are not standardized and do not enable equivalent testing.

Elektrokemijske metode, elektrokemijska impedancijska spektroskopija i metoda diferencijalnog kapaciteta su korištene u ovom radu u svrhu istraživanja degradacijskih mehanizama litij-ionskih galvanskih članaka. Testiranja su provođena na odabranom litij-polimernom galvanskom članku (model cCellevia LP402030) nominalnog kapaciteta 190 mA h. Degradacija članka je provođena sukcesivnim punjenjem i pražnjenjem u rasponu napona 2, 75 – 4, 2 V kroz 300 ciklusa. Nakon svakih 50 ciklusa konstruiran je Ragoneov graf, snimljeni impedancijski spektri te snimljena krivulja ovisnosti diferencijalnog kapaciteta o naponu. Rezultati su pokazali da se opetovanim punjenjem i pražnjenjem galvanski članak degradira. Kao uzrok degradacije identificiran je nastanak i rast međusloja čvrstog elektrolita (SEI) u koji se ugrađuju litijevi ioni iz elektrolita te dovode do otežane difuzije litijevih iona iz elektrolita do elektrode i obrnuto.

Celuloza je najrasprostranjeniji prirodni polimer. Sve se više istražuje radi korištenja u medicinske i industrijske svrhe, prije svega zbog svoje biorazgradivosti, biokompatibilnosti, široke dostupnosti i neškodljivosti. Cilj ovog rada sintetizirati je hidrogelove celuloze graftirane sa N-vinil-2-pirolidonom i umrežene sa N,N-metilen-bis-amidom (MBA) na dva načina; izravnom sintezom i zračenjem, te usporediti njihova svojstva. Kemijska reakcija celuloze i N-vinil-2-pirolidona (omjer 1:1, 1:3 i 1:5 mol/mol) provedena je u sustavu otapala N,N-dimetilacetamid/LiCl s peroksidnim inicijatorom pri 90°C uz N,N-metilen-bis-akrilamid kao umreživač. Mikrostruktura pripravljenih hidrogelova ispitana je pretražnom elektronskom mikroskopijom. Sintetizirani hidrogelovi karakterizirani su FTIR spektroskopijom. Hidrogelovima je određivan stupanj bubrenja u deioniziranoj vodi, a odabrani sustavi su ispitani u kiselini i lužini. Temeljem omjera intenziteta karakterističnih vrpci pri 1645-1660 cm^-1 i 897 cm^-1 utvrđeno je značajno povećanje nakon zračenja sa 10 kGy naspram hidrogela priređenog kemijskom sintezom. S povećavanjem doze zračenja na 30 kGy smanjuju se omjeri intenziteta u hidrogelovima obje serije uzoraka, a dodatnim zračenjem na 100 kGy ne dolazi do značajne promjene intenziteta. Provedbom pokusa bubrenja u periodu od 2 mjeseca najveći stupanj bubrenja zabilježen je kod serije uzoraka 1:3-100 kGy. Pretražnom elektronskom mikroskopijom utvrđeno je da ozračivanje značajno doprinosi povećanju poroznosti pripravljenog hidrogela kao i da nakon osmotjednog bubrenja sfere pokazuju značajnu deformaciju oblika. Cellulose is the most common natural polymer. It has been intensively researched for medical and industrial purposes due to its biodegradability, biocompatibility, availability and harmlessness. The focus of this research paper it the synthesis of cellulose hydrogels grafted with N-vinyl-2pyrrolidone and crosslinked with N,N-methylenebisacrilamide (MBA) in two different ways, namely by direct synthesis and synthesis by radiation, as well as the comparison of their properties. The chemical reaction of cellulose and N-vinyl-2-pyrrolidone was carried out in the solvent N,N-dimethyl acetamide/LiCl with a peroxide initiator at the temperature of 90°C and using N,N-methylene-bis-acrylamide as a crosslinker. Microstructure of prepared hydrogels were examined by scanning electron microscopy. The synthesised hydrogels are characterized by FTIR spectroscopy. The degree of swelling was controlled in unionized water, as well as in an acidic- and an alkaline solution for some systems. Based on the ratio of intensity of a band at 1645-1660 cm^-1 and 897 cm^-1, it has been concluded drastically increase after irradiation of 10 kGy compared to the hydrogel prepared by chemical synthesis. Furthermore, the ratio of intensity in hydrogels in both series lowers by increasing the radiation to 30 kGy. Finally, with an excess radiation of 100 kGy, there is no change in the intensity. During the period of two months during which the experiment was being conducted, the greatest level of swelling occurred in the series 1:3-100 kGy. By using scanning electron microscopy, it has been determined that 1.) radiation significantly increases porosity of prefabricated hydrogel and 2.) after eight weeks of swelling, the sphere shows a significant shape deformation.

U ovom radu testiran je litij-polimer galvanski članak, komercijalni članak LP402030 / 190 mAh. Za testiranje korištene su elektrokemijske metode. Stanje članka se određivalo na početku, kada je članak nov, te nakon degradacije. Također, pratilo se stanje napunjenosti (SoC) članka te stanje zdravlja (SoH). Glavni cilj rada je ukazati na karakteristike članka, ali i promjene tih karakteristika koje se javljaju zbog degradacije. Također, cilj je otkriti koji su uzroci degradacijskih procesa u članku. Elektrokemijske metode koje su korištene se elektrokemijska impedancijska spektroskopija, punjenje i pražnjenje članka konstantnom strujom, a iz toga konstrukcija Ragoneovih dijagrama te kulometrija visoke preciznosti. Sve tri metode su korištene na novoj bateriji te nakon prve degradacije, dok je elektrokemijska impedancijska spektroskopija korištena i nakon druge degradacije. Razlike u spektrima dobivenima elektrokemijskom impedancijskom spektroskopijom se vide u pomacima impedancijskih spektara, Ragoneovi dijagrami pokazuju da dolazi do smanjenja energija nakon degradacije, a kulometrija visoke preciznosti pokazuje da se kulonska učinkovitost smanjila nakon degradacije. Na kraju se impedancijski spektri modeliraju ekvivalentnim električnim krugom koji daju sličan odziv kao i eksperimentalni rezultati. Ekvivalentni krugovi najbolje opisuju fizikalno-kemijske procese koji se odvijaju u članku. Najčešći uzroci degradacije su formiranje SEI sloja te njegovo podebljanje, otpor difuziji iona te procesi povezani s kinetikom elektrona. Svi ti procesi su neizbježni. Stanje zdravlja članka pada s porastom stupnja degradacije, a s degradiranjem dolazi i do smanjenja životnog vijeka galvanskog članka.

This paper analyses the concept of hell in John Milton’s Paradise Lost and its relationship with one of the most prominent characters in the epic poem, Satan. The paper describes the physical aspects of Milton’s hell, Satan, his fall of grace, the question of his heroism, self-deception and degradation and the way all the above relates to hell as a both physical and mental concept. It considers the relationship of physical and mental hell that manifests around and in the character of Satan., Ovaj rad analizira koncept pakla u herojskom epu Izgubljeni raj Johna Miltona i odnos između pakla i jednog od istaknutijih likova u epu, Sotonom. Rad opisuje fizička obilježja Miltonovog pakla, Sotonu, njegov pad iz raja, pitanje njegovog heroizma, samozavaravanje i degradaciju te način na koji je sve od navedenog povezano s paklom kao fizičkim i mentalnim konceptom. Rad razmatra odnos fizičkom i mentalnog pakla koji se očituje u njegovom vanjskom okruženju, ali i samom liku.

Dezertifikacija je proces degradacije zemljišta u sušnim, polusušnim te umjereno vlažnim područjima. Prisutna je na svim kontinentima te znanstvenici smatraju da je rezultat klimatskih varijacija/promjena i ljudske aktivnosti. Tema ovog rada je dezertifikacija na primjeru otoka Paga. Cilj rada je ukazati na problem dezertifikacije na spomenutom otoku, te istražiti uzroke istog. U radu se analizira povijest otoka, razvoj poljoprivrede, gospodarstva i turizma te istražiti kako su navedene djelatnosti utjecale na pojavu i širenje dezertifikacije u prošlosti, kao i danas. Uspoređuje se stanje nekad i sad te objasniti što je uzrokovalo promjenu. Također, pretpostavit će se budući procesi, moguće mjere ka poboljšanju situacije te posljedice koje su vidljive na otoku. Pri izradi rada korišteni su sekundarni izvori i statistički podaci. Ova tema je aktualna zbog sve većeg iskorištavanja prirodnih resursa što u konačnici dovodi do degradacije tla, smanjenja bioraznolikosti i erozije. Desertification is a process of land degradation in arid, semi-arid and moderately humid areas. Being present on every continent, the scientists believe it to be the result of climatic variations and human activity. The topic of this paper is desertification of the island of Pag. The goal of the paper is to emphasise the island's potential desertification issue, as well as explore its causes. The paper retrospects on the history, agriculture, tourism and the economy of the island and explore what effect these activities had on the spread and occurrence of desertification in the past, as well as today. The prior and current situation are compared and contrasted in order to analyse the changes that occurred. In addition, future desertification on the island of Pag is projected, as well as consequences of prior desertification and possible measures towards amelioration of the current situation. Sources used during the production of paper include secondary sources alongside statistical data. This topic is currently relevant because of the growing rate of natural resource exploitation which, in turn, leads to erosion, degradation of soil and land, as well as the reduction of biodiversity.

Research in protein aggregation and other degradation routes is of major importance in recent years, influencing the quality and consistency of biopharmaceutical drugs used to treat various life-threatening conditions. In this work we study the open soft-matter physics questions behind such processes that affect developability, safety and efficacy of aqueous solutions of therapeutic proteins. The focus lies on processes of irreversible aggregation and reversible self-association, which can be most influenced by the physical properties of the solution. Physico-chemical interactions reflected in colloidal and conformational stability are evaluated with dynamic light scattering (DLS) and induced protein denaturation. Thermal denaturation is measured via differential scanning calorimetry (DSC). Guanidium hydrochloride and urea are used as chemical denaturants and the ensuing unfolding is measured via tryptophan fluorescent response. The physical effect of excipients such as salts and sugars on protein stability is evaluated. Irreversible aggregation is accelerated mostly with elevated temperature and measured with size exclusion chromatography (SEC), resonant mass measurement (RMM) and micro-flow imaging (MFI). A Smoluchowski type system of differential equations, describing the kinetics of binary aggregation on multiple size scales, is numerically solved in parallel, with the model output compared with experimental data, explaining several phenomena specific to protein aggregation. Adhesion of proteins and protein particles in the micrometer size range to surfaces of containers is characterised with atomic force (AFM) and optical microscopy. We identify several different regimes of particle formation, adhesion to surfaces, and accumulation in bulk solution, shown to have a major impact on determination of particle formation propensity based on elevated temperature studies. We evaluate the discrepancies with mean-field Smoluchowski type models in this non-colloidal regime. Reversible self-association resulting in increased solution viscosity is measured with microfluidic rheometry. The factors contributing to viscosity of protein solutions are analysed and evaluated. A novel interaction mechanism contributing to viscosity is proposed. Finally, this work is a contribution towards advanced protein formulation development with special emphasis on development of biopharmaceuticals. V zadnjih letih narašča pomembnost raziskav procesov kot so agregacija in degradacija proteinov, ki vplivajo na kvaliteto bioloških zdravil za zdravljenje različnih bolezenskih stanj. V tezi raziskujemo tematike fizike mehke snovi v povezavi s temi procesi, od katerih zavisi razvoj, varnost in učinkovitost vodnih raztopin terapevtskih proteinov. Osredotočamo se predvsem na procese nereverzibilne agregacje in reverzibilnega povezovanja proteinskih molekul, na katere lahko v veliki meri vplivamo s fizikalnimi lastnostmi raztopin. Fizikalno-kemijske interakcije, ki vplivajo na koloidno in konformacijsko stabilnost, ovrednotimo z dinamičnim sipanjem svetlobe (DLS) in denaturacijo. Termično denaturacijo merimo z diferencialno kalorimetrijo (DSC). Kot denaturante za kemično denaturacijo uporabljamo gvanidinijev klorid in ureo, merimo pa jo prek fluorestenčnega odziva triptofanov. Ovrednotimo fizikalni vpliv pomožnih snovi v zdravilu (ekscipientov), kot so soli in sladkorji. Tvorbo nereverzibilnih agregatov pospešimo s povišano temperaturo in merimo z izključitveno kromatografijo (SEC), resonančnim merjenjem mase (RMM) in pretočno mikroskopijo (MFI). Vzporedno z eksperimentom numerično rešimo sistem enačb po vzoru Smoluchowskega, ki opisujejo kinetiko binarne agregacije na večih velikostnih skalah, in primerjamo dobljene rezultate z eksperimentom. Tako pojasnimo osnovne pojave, povezane z agregacijo proteinov. Z mikroskopom na atomsko silo (AFM) in optično mikroskopijo raziskujemo adhezijo proteinov in proteinskih delcev na površine vsebnikov. Opišemo več režimov tvorbe delcev v raztopini in njihovega prijemanja na površine, ki imajo pomemben vpliv na interpretacijo rezultatov meritev vsebnosti delcev po študijah pri povišani temperaturi. Komentiramo tudi odstopanje rezultatov od teoretičnih napovedi modela Smoluchowskega zaradi posedanja in adhezije. Reverzibilno povezovanje proteinskih molekul, katerega makroskopski vpliv se kaže v povišani viskoznosti, merimo z mikrofluidno reometrijo. Razločimo in analiziramo različne faktorje, ki vplivajo na viskoznost. Predlagamo nov mehanizem, ki povezuje povišanje viskoznosti z elektrostatskimi interakcijami. To delo prispeva k napredku razvoja proteinskih formulacij, s posebnim poudarkom na razvoju bioloških zdravil.

Policiklični aromatični ugljovodonici (engl. Polycyclic Aromatic Hydrocarbons, PAHs) predstavljaju grupu organskih jedinjenja koja se sastoje od dva ili više kondenzovanih benzenovih prstenova. Istraživanja ukazuju da PAH-ovi imaju kancerogen i mutagen uticaj na ljude i druge žive organizme. Perzistentni su i bioakumulativni i kao takvi predstavljaju opasnost po životnu okolinu. Dodatni problem predstavljaju proizvodi degradacije policikličnih aromatičnih ugljovodonika, koji nastaju tokom prirodne transformacije ili fizičko-hemijskih tretmana za njihovo uklanjanje. Novoformirana jedinjenja često imaju izraženiji toksični uticaj na ljude i druge žive organizme u poređenju sa polaznim jedinjenjem. Zato se posebna pažnja posvećuje razvoju novih metoda za njihovo što bezbednije uklanjanje. Do sada su razvijene metode za analizu sledećih kontaminiranih medijuma: voda, zemljište, vazduh, sedimenti i dr. Kako je zagađenost PAH-ovima u životnoj sredini rasla, uglavnom usled antropogenih faktora, tako su se pojavili i na drugim mestima, poput betona u stambenim zgradama. Cilj istraživanja doktorske disertacije je razvijanje nove, efikasne, neinvazivne metode za uklanjanje PAH-ova iz betona, koja je zasnovana na elektrohemijskoj oksidaciji. Da bi se osigurala bezbednost metode za praktičnu primenu, posebna pažnja posvećena je proceni toksičnosti PAH-a i njihovih produkata razgradnje nastalih tokom procesa elektrooksidacije. Kao laboratorijski model sistem za elektrohemijsku degradaciju PAH-ova koristi se elektrolitička ćelija sa niklenim elektrodama. Praćenje koncentracije PAH-ova u betonu izvedeno je primenom novopostavljene i validirane metode na uređaju tečni hromatograf ultravisokih performansi sa fotodiodnim detektorom (UPLCPDA). Efikasnost uklanjanja za pojedine PAH-ove dostiže vrednost i preko 90 %. Za procenu toksičnosti elektrohemijskog tretmana određuje se citotoksični i genotoksični potencijal na limfocitima i eritrocitima periferne krvi čoveka. Testoviobuhvataju određivanje učestalosti mikronukleusa i proliferacioniog potencijala ćelija, ispitivanje antioksidativne zaštite enzima (katalaze) kao i uticaja na oksidativni stres (određivanjem sadržaja malondialdehida). Rezultati ispitivanja potvrđuju toksičnost početne smeše PAH-ova - pre elektrohmijske oksidacije - uzrokujući značajno povećanje niva DNK oštećenja, smanjujući potencijal ćelija za deobu i indukujući oksidativni stres što se ogleda kroz povećanje malondialdehida u procesu lipidne peroksidacije ćelijskih membrana i povećanju aktivnosti katalaze, enzima antioksidativne odbrane. Procesom elektrohemijske oksidacije PAH-ova nastaju produkti koji ispoljavaju različit stepen citotoksičnosti zavisno od vremena nastanka. Najtoksičniji efekti su utvrđeni u prvih 15 minuta što se manifestuje kroz povećanje učestalosti genomskih ozleda, suprimiranje proliferativnog potencijala i/ili indukciju oksidativnog stresa, kao i značajanu modifikaciju aktivnosti enzima antioksidativne zaštite. Nakon 60 minuta produkti oksidacije su manje citotoksični u odnosu na početno jedinjenje, ali i dalje su toksičniji u poređenju sa netretiranom kontrolom. Polycyclic Aromatic Hydrocarbons (PAHs) are a group of organic compounds consisting of two or more fused benzene rings. Research indicates that PAHs have a carcinogenic and mutagenic effect on humans and other living organisms. They are persistent and bioaccumulative and, as such, pose a threat to the environment. Products that are formed upon natural degradation or physicochemical procedures for their removal represent a particular problem. Newly formed compounds often have a more pronounced toxic effect on humans and other living organisms compared to the initial compound. Consequently, the development of new methods for their safe removal has been the subject of extensive research. So far, methods for efficient PAH removal from the various media were developped, including: water, soil, air, sediments, etc. As the environmental pollution by PAHs is continuously increasing due to the various, mainly anthropogenic factors, they also have occurred in other places, such as concrete in residential buildings. The aim of the doctoral dissertation is to develop novel, efficient, noninvasive method for PAHs removal in concrete, based on electrochemical oxidation. In order to ensure safeness of the method for practical application, particular attention was paid to the estimation of the toxicity of PAHs and their degradation products generated during the electrooxidation process. Electrochemical cell consisting of two nickel electrodes was used for the laboratory model of PAH oxidation in concrete. Concentration of PAHs in concrete was monitored with the novel, particularly developed and validated method, based on ultra performance liquid chromatography (UPLC) with photo-diode array (PDA) detector. The removal efficiency for individual PAHs exceeds 90 %. Estimation of the toxicity of electrochemically treated samples was performed by determination of the cytotoxic and genotoxic potential of human peripheral blood lymphocytes and erythrocytes. The tests included determination the micronucleusfrequency and the proliferative potential of cells, determining the antioxidant protection of enzyme catalase, as well as the impact on oxidative stress (by determining the content of malondialdehyde). The results of the study confirm the toxicity of initial PAHs showing that - before electrochemical oxidation - they significantly increase the level of DNA damage, reduce the potential of cells to divide and induce oxidative stress, which is reflected by the increase of malondialdehyde in the process of lipid peroxidation of cell membranes and the increase of the activity of catalase, an antioxidant defense enzyme. Products which are formed during electrochemical oxidation of PAHs exhibit different degrees of cytotoxicity depending on the time of their formation. The most toxic effects were determined in the first 15 minutes, which is manifested by an increased incidence of genomic lesions, suppression of proliferative potential and/or induction of oxidative stress, as well as substantial modification of the antioxidant enzyme activity. After 60 minutes, the oxidation products are less cytotoxic than the parent compound, but still more toxic compared to the untreated control.