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AR Chemistry edukativna je aplikacija koja korisniku omogućuje vizualizaciju i interakciju s atomima i molekulama uz pomoć proširene stvarnosti. Budući da je jedna od najpopularnijih namjena proširene stvarnosti upravo edukacija, ova tehnologija je odabrana kao osnova aplikacije zbog svoje ugrađene sposobnosti vizualizacije pri objašnjavanju koncepata koji zahtijevaju razumijevanje prostornih odnosa. Za izradu aplikacije korištena je Vuforia za AR funkcionalnosti te Unity pri samom razvoju aplikacije. Dobivena aplikacija se može instalirati i koristiti na Android pametnim mobilnim uređajima s AR sposobnostima. AR Chemistry is an educational application that allows the user to visualize and interact with atoms and molecules with the help of augmented reality. Since one of the most popular use cases for augmented reality is education, this technology was chosen as the base of the application for its embedded visualization ability while explaining concepts that require understanding of spatial relations. To develop the application, Vuforia was used for AR functionalities and Unity for developing the app in general. The built version of the app can be installed and used on Android smart devices that have AR capabilities.

Izvajanje pouka v šolah pogosto poteka na tradicionalen način s frontalnim poučevanjem in predavateljem v središču pozornosti, kljub temu da je za kakovostno usvajanje znanja, spretnosti in veščin bistveno zagotoviti okolje, v katerem so v središču aktivni učenci. Informacijsko-komunikacijska tehnologija omogoča preoblikovanje učnega procesa, ena od takšnih možnosti je uporaba poddaj. Raziskave kažejo, da slednje omogočajo dobro alternativo tradicionalnemu načinu učenja in poučevanja kemije, vendar ga samo z uporabo poddaj ne more v celoti nadomestiti. Pri pouku kemije predstavlja uporaba poddaj inovativen pristop, ki pa od avtorja učnih enot zahteva več priprav in poglobljeno delo, predvsem pri poučevanju slovensko govorečih učencev, saj je količina slovenskih poddaj omejena. Ker na slovenskem prostoru še ni bilo narejene raziskave s področja uporabe poddaj pri pouku kemije, je namen tega magistrskega dela ovrednotiti uporabno vrednost poddaj pri pouku kemije. Z uporabo svetovnega spleta in člankov sem pregledal področje uporabe poddaj pri pouku kemije. Z vprašalnikom sem preveril, kaj o uporabi in o ustvarjanju lastnih poddaj za učenje kemije menijo dijakinje in dijaki, z intervjuvanjem izbranih srednješolskih učiteljic pa sem spoznal, na kakšen način se poddaje morda že uporabljajo pri pouku kemije v Sloveniji ter kakšne prednosti in omejitve glede njihove uporabe prepoznavajo učitelji kemije. Ugotovil sem, da srednješolci podpirajo uporabo poddaj, zlasti video različic, za učenje kemije, a prednost dajejo tradicionalnim oblikam učenja. Za ustvarjanje lastnih poddaj ne kažejo velikega interesa, se pa učiteljicam ta aktivnost zdi zelo poučna. Pravijo, da pri svojem delu poddaj ne uporabljajo pogosto, raje se poslužujejo drugih aktivnosti. Največjo oviro vidijo v časovni stiski s sledenjem učnim ciljem po učnem načrtu. Magistrsko delo utira pot novim spoznanjem o uporabi poddaj na področju raziskovanja v kemijskem izobraževanju in predstavlja velik doprinos pedagogiki kemije. Education in schools often takes place in the traditional way, with frontal, teacher-centred instruction, even though it is essential for best acquisition of knowledge, skills and abilities to provide a student-centred environment. Information and communications technology enables transformation of the learning process. One of such possibilities is the use of podcasts. Research shows that podcasts provide a good alternative to the traditional way of learning and teaching chemistry, but it cannot be completely replaced by using podcasts alone. The use of podcasts in chemistry is an innovative approach, which requires more preparation and in-depth work from the teacher, especially in the teaching of Slovene-speaking students, as the number of Slovene podcasts is limited. As no research has yet been done in Slovenia in the field of the use of podcasts in chemistry lessons, the purpose of this master's thesis is to evaluate the usefulness of podcasts in chemistry lessons. Using the World Wide Web and research articles, I reviewed the field of application of podcasts in chemistry lessons. With the questionnaire I investigated what students think about the use and creation of their own podcasts for learning chemistry, and by interviewing selected high school teachers I found out how podcasts may already be used in chemistry lessons in Slovenia and what advantages and limitations of their applications are recognized by chemistry teachers. I have found that high school students support the use of podcasts, especially video versions, for learning chemistry, but they prefer traditional forms of learning. They do not show much interest in creating their own podcasts, but the teachers find this activity very instructive. Teachers report that they do not use podcasts often in their work. They prefer to use other activities and see the biggest obstacle in time constraints by following the learning goals according to the curriculum. The master's thesis paves the way for new insights into the use of podcasts in the field of research in chemical education and represents a major contribution to the pedagogy of chemistry.

As the global demand for propene (propylene) is increasing, classic commercial production processes are becoming unable to keep up. Non-oxidative dehydrogenation, although hitherto underutilised industrially, has been put forward as a viable and green alternative, which is already used in a few commercial processes. In this work, we present detailed first-principles calculations of this reaction over a chromium oxide catalyst, which is the cornerstone of the Catofin ® process. A complete reaction pathway for the dehydrogenation of propane to propene and ultimately to propyne (methylacetylene) was considered. Cracking, which can yield C1 and C2 hydrocarbons, and the deactivation of the catalyst because of coking were also included and modelled. We used density functional theory calculations with the Hubbard model to study the structure of the involved intermediates, their adsorption and their interconversion to explain how chromium oxide catalysts facilitate this reaction and which processes cause their deactivation. We showed that the interaction of the hydrocarbons and molecular hydrogen with the catalytic surface is rather weak, resulting in low surface coverages, but increasing with multiple bonds present in hydrocarbons. Having constructed the potential energy surface with all the intermediates and the transition states linking them, we proposed a kinetic model for the reaction. Kinetic Monte Carlo simulations were performed at experimentally relevant temperatures (700–1000 °C), pressures (up to 10 bar) and inlet mixture compositions to study the kinetics of the reaction and discover the rate determining steps. As the reaction is highly endothermic, considerable conversions only occur at high temperatures. The accumulation of propene and propyne in the reaction mixture adversely affects the reaction rate and selectivity. Higher pressures increase the reaction rate but also increase the rate of coke formation, which poisons the catalyst. Deactivation of the catalyst has a strong temperature dependence and is caused by the accumulation of C∗ and CH3CC∗ on the surface, which are hard to remove even with hydrogen.

The Eighth Central European Conference “Chemistry towards Biology” was held in Brno, Czech Republic, on 28 August–1 September 2016 to bring together experts in biology, chemistry and design of bioactive compounds promote the exchange of scientific results, methods and ideas and encourage cooperation between researchers from all over the world. The topics of the conference covered “Chemistry towards Biology”, meaning that the event welcomed chemists working on biology-related problems, biologists using chemical methods, and students and other researchers of the respective areas that fall within the common scope of chemistry and biology. The authors of this manuscript are plenary speakers and other participants of the symposium and members of their research teams. The following summary highlights the major points/topics of the meeting.

The methane activation and methane dry reforming reactions were studied and compared over 4 wt % Ni/CeO2 and 4 wt % Ni/CeZrO2 (containing 20 wt % Zr) catalysts. Upon the incorporation of Zr into th...

The production of biobased copolymers such as poly(styrene-co-butyl acrylate-co-methacrylic acid) for paints and coating applications is indispensable for the establishment of sustainable biorefine...

IR spectroscopy can be a non-destructive and straightforward probing tool in the battery research. However, its application has been limited due to the difficulties related to the handling and interpretation of ex situ samples along with the lack of widely applicable in situ and operando cells. Herein, we show a simple, operando ATR-IR two electrode pouch cell with an IR-transmissive silicon window and discuss its advantages and limitations. This setup is applied to the study of the polyanthraquinone (PAQ) reaction mechanism in Li- and Mg-organic batteries. During the reduction/oxidation process of the PAQ, not only the conversion of both C O groups into C–O– species is observed, but also the formation of an intermediate semiquinone radical anion as an intermediate product. Furthermore, continuous measurement of IR spectra allows visualization of the gradual solid-electrolyte interphase (SEI) buildup on the cathode during cycling.

U ovome radu objašnjene su osnove tehnologije proširene stvarnosti te glavni koncepti u procesu njezine izvedbe. Opisana je primjena proširene stvarnosti na području obrazovanja, a poseban naglasak stavljen je na proširenoj stvarnosti u aplikacijama i igrama vezanim uz kemiju. Izrađen je prototip obrazovne aplikacije koja sadrži elemente proširene stvarnosti s fokusom na kemijske spojeve. Aplikacija je implementirana u Unity razvojnom okruženju uz korištenje Vuforia programskog alata. Cilj ove aplikacije je brže i bolje usvajanje znanja o kemijskim spojevima uz pomoć interaktivnih elemenata proširene stvarnosti. Korisnik uči tako da pronalazi objekte iz vlastite okoline na temelju kojih bi se prikazao kemijski spoj koji je glavni gradivni element tog objekta i neke zanimljivosti vezane uz taj spoj. This paper explains the basics of augmented reality technology and the fundamental concepts in the process of its implementation. The use of augmented reality in the field of education is described, and special emphasis is placed on augmented reality applications and games based on chemistry. A prototype of an educational application containing augmented reality elements with a focus on chemical compounds was developed. The application is implemented in a Unity development platform using the Vuforia software tool. The primary purpose of this application is the faster and better acquisition of knowledge about chemical compounds with the help of the augmented reality interactive elements. The user learns by finding specific objects from his environment. When the object is detected, the main chemical compound of that object and some interesting facts related to that compound are shown on the screen.

The enzyme-catalyzed degradation of the biogenic amine serotonin is an essential regulatory mechanism of its level in the human organism. In particular, monoamine oxidase A (MAO A) is an important flavoenzyme involved in the metabolism of monoamine neurotransmitters. Despite extensive research efforts, neither the catalytic nor the inhibition mechanisms of MAO enzymes are currently fully understood. In this article, we present the quantum mechanics/molecular mechanics simulation of the rate-limiting step for the serotonin decomposition, which consists of hydride transfer from the serotonin methylene group to the N5 atom of the flavin moiety. Free-energy profiles of the reaction were computed by the empirical valence bond method. Apart from the enzymatic environment, the reference reaction in the gas phase was also simulated, facilitating the estimation of the catalytic effect of the enzyme. The calculated barrier for the enzyme-catalyzed reaction of 14.82 +/- 0.81 kcal mol(-1) is in good agreement with the experimental value of 16.0 kcal mol(-1), which provides strong evidence for the validity of the proposed hydride-transfer mechanism. Together with additional experimental and computational work, the results presented herein contribute to a deeper understanding of the catalytic mechanism of MAO A and flavoenzymes in general, and in the long run, they should pave the way toward applications in neuropsychiatry.

Organocatalyzed ring-opening polymerization (ROP) of e-caprolactone (CL) and 4,4′-bioxepanyl-7,7′-dione as a bis-lactone cross-linker was performed within the oil-in-oil high internal phase emulsions (HIPEs) at 50 °C. In this way, the cross-linked poly(e-caprolactone) (PCL) polyHIPE foams of ∼85% porosity were synthesized. Thermomechanical properties of the prepared polyHIPEs were studied and proved to greatly depend on a degree of PCL cross-linking. The melting and crystallization temperatures as well as the degree of crystallinity of PCL polyHIPE foams decrease with an increasing cross-linking degree. Semi-crystalline polyHIPEs demonstrate shape memory behavior with excellent shape fixity and shape recovery. At an appropriate degree of PCL cross-linking, the polyHIPE temporary shape can be fixed at room temperature, while a transition to the permanent shape occurs upon heating at 40 °C. Moreover, a two-way shape memory behavior of the PCL polyHIPEs under constant stress was observed.

Despite the fact that the methanol synthesis process includes industrially some of the most important catalytic chemical reactions, it is still not clear how different gaseous species impact cataly...

V diplomskem delu sem obravnaval delo Kmetijska kemija, avtorja Matije Vertovca, ki velja za prvi kemijski priročnik v slovenskem jeziku. V uvodu sem predstavil Vertovčevo življenje in delo, opisal pa sem tudi nezanemarljiv pomen, ki ga je imel in ima Vertovec in njegovo delo za slovenski jezik in narod. Poglavitni cilj in namen diplomske naloge je bila analiza kemijskih terminov, ki jih je Vertovec zapisal v svojem delu Kmetijska kemija. Iz prvega poglavja Vertovčevega dela sem izpisal vse termine, za katere menim, da sodijo na področje kemijske terminologije, jim v Kemijskem slovarju poiskal ustrezne definicije ter s pomočjo Slovenskega etimološkega slovarja preverjal njihov izvor. Ugotavljal sem torej, koliko terminov je prevzel iz nemškega, grškega, latinskega jezika, koliko je vzel izrazov, ki so bili v slovenskem jeziku že zakoreninjeni in uveljavljeni in koliko je takih, ki jih je najverjetneje poslovenil kar sam. Ugotovil sem, da je večina izrazov izvor v slovanski jezikovni veji, torej so bili že zakoreninjeni v slovenskem jeziku. In my degree I did a research on the literary work called Agricultural chemistry (Kmetijska kemija) by Matija Vertovec, this is the first chemistry manual written in Slovene language. In the introduction part of my work I presented the life and work of the author Matija Vertovec and then deepened my research with the importance of the author and his work for the Slovene language and the Slovene nation. After that, I moved to the main aim of my degree, which was to analyse the etymology of terms used in the manual. Firstly, I collected and analysed all the terms written in the first chapter of the manual, for which I thought belong to the field of chemical terminology. Then I found their definitions with the help of The Chemical dictionary (Kemijski slovar) and furthermore used The Etymology dictionary (Etimološki slovar) to research upon their origin. I was trying to explore how many terms were taken over from the German, Greek and Latin language. I also investigated the terms that were already known and established in the Slovene language and used in the manual. Lastly, I searched for those terms that the author has translated into Slovene himself. My research showed that most of the terms had their origins in the Slavic language branch and were therefore already known and established in the Slovene language.

V sodobni organski kemiji znanstveniki razpoznavajo organske spojine iz različnih naborov spektrov, kjer vsak posamezni spekter vsebuje podatke o teh spojinah, kot so vsebovani element, struktura, itd. Kemiki so veliko spojin že posneli in razpoznali, računalničarji pa izdelali programe, ki s pomočjo iskanja po podatkovnih bazah najdejo preiskovano spojino. Kljub temu kemiki vedno znova odkrivajo oz. srečujejo nove, do sedaj še neznane spojine, ki jih je potrebno ročno prepoznati oz. razvozlati, za kar lahko potrebujejo dlje časa, lahko tudi več ur ali v primeru zelo kompleksnih molekul, več dni. V okviru diplomske naloge je bil razvit algoritem, ki organske spojine analitično razpoznava, brez vnaprej znane podatkovne baze. Z uporabo IR, NMR in MS spektrov je bilo mogoče dobiti zadovoljive rezultate pri reševanju organskih molekul. Algoritem, ki je nastal v okviru diplomskega dela, je javno dostopen v obliki spletnega aplikacijskega vmesnika (ang. application programming interface - API), za katerega je bil izdelan tudi uporabniški vmesnik za enostavnejšo uporabo. In modern chemistry scientists elucidate organic compounds from different sets of spectrums in which every spectrum contains it's own information about the compound i.e.: known fragments, structure, etc. Since chemists have solved and documented a lot of these compounds computer scientists quickly created softwares which, with the help of an external databases, find the researched compound. Regardless chemists still discover new yet unrecorded compounds that they need to elucidate by hand which can take them multiple hours or, in case of highly complex molecules, even days. With this purpose an algorithm, described in this document, was developed which analitically solves organic compounds without the use of any external database. By using IR, NMR and MS spectrums the algorithm was able to get accurate results while elucidating organic compounds. The developed algorithm is available to the public in the form of a web application interface together with a user interface for simple usage.

Semi-interpenetrating polymer networks (semi-IPNs) were prepared by in situ simultaneous orthogonal polymerizations, where the linear poly(e-caprolactone) (PCL) was synthesized by ring-opening polymerization of e-caprolactone and the poly(styrene-co-divinylbenzene) (PS) network was formed by free-radical polymerization of styrene/divinylbenzene. Semi-IPNs were used as the precursors for the preparation of porous PS monoliths. To this end, the PCL domains were selectively removed by hydrolysis under basic conditions. By changing the amount of organocatalyst used for the ring-opening polymerization of e-caprolactone, the relative polymerization kinetics of both monomers was varied, which has a pronounced effect on the morphology of thus-obtained PS frameworks.

Methane is the central component of natural gas, which is globally one of the most abundant feedstocks. Due to its strong C–H bond, methane activation is difficult, and its conversion into value-added chemicals and fuels has therefore been the pot of gold in the industry and academia for many years. Industrially, halogenation of methane is one of the most promising methane conversion routes, which is why this paper presents a comprehensive review of the literature on methane activation by halogenation. Homogeneous gas phase reactions and their pertinent reaction mechanisms and kinetics are presented as well as microkinetic models for methane reaction with chlorine, bromine, and iodine. The catalysts for non-oxidative and oxidative catalytic halogenation were reviewed for their activity and selectivity as well as their catalytic action. The highly reactive products of methane halogenation reactions are often converted to other chemicals in the same process, and these multi-step processes were reviewed in a separate section. Recent advances in the available computational power have made the use of the ab initio calculations (such as density functional theory) routine, allowing for in silico calculations of energy profiles, which include all stable intermediates and the transition states linking them. The available literature on this subject is presented. Lastly, green processes and the production of fuels as well as some unconventional methods for methane activation using ultrasound, plasma, superacids, and light are also reviewed.

A new species’ class of Cu-, Ga- and Zn-based rate catalysts was prepared by a systematic co-precipitation technique at the different related pH values (6.5–8.0) along with calcination functional conditions, influencing components’ physical properties, these were characterized, and their application performance for water–gas shift (WGS) reaction was researched. Substances were analysed by various experimental methods, namely chemisorption, temperature-programmed reduction (TPR) characterisation, diffraction, physisorption and microscopy. A homogenous size dispersion of the compounds with smaller granular particles was obtained for catalysis, implemented with high pH-resulting outputs. H2 TPR profiles revealed a tailored stronger effect of Cu–Zn on Ga for process, operated with low pH-conditioned forms. Over Cu/ZnGaOX, WGS was sensitive to Cu, which was primarily active. Catalytic chemical reactivity, activity and selectivity were also found to be critically dependent on material lattice structure, copper surface area and metal–support interaction phenomena. The temperature-programmed surface reaction with mass spectrometry (TPSR–MS) measurements showed that formulations, synthesised at the pH of 8.0, enabled reaching >99% of the equilibrium yield CO conversion at 260 °C. An increase in the converted CO, oxidation and H2 productivity with the integral steam content in gaseous feed flow was achieved. The heterogeneous phase processing at the correlated pH of 7.6 demonstrated the highest formed CO product at the temperature of 200 °C, compared with literature. This is particularly promising for reagent purity hydrogen-fed fuel cells. The kinetics for each co-precipitated solid was evaluated regarding the efficiency for the WGS in a fixed bed reactor. Keywords: Syngas, Hydrogen, Cu/ZnGaOX catalyst, Water–gas shift (WGS), Steam reforming reactions, Fuel cell systems

V podporo razumevanju naravoslovnih pojmov in procesov na ravni delcev so v učna gradiva vključene različne predstavitve (reprezentacije). Članek se osredotoča na preučevanje, kako so submikroskopske reprezentacije (SMR-ji) integrirane v slovenske kemijske učbeniške komplete v povezavi z vsebinami učnega načrta za osnovno šolo. Izhodišče za analizo učbeniškega gradiva so predstavljali štirje holistični deskriptorji SMR-jev (direktni, indirektni, kombinirani deskriptor in SMR-ji brez deskriptorjev), ki glede na specifične opisnike SMR-jev do različne mere podpirajo učenca pri prepoznavanju informacijske vrednosti SMR-jev. Analiza učbeniških kompletov je pokazala, da se število SMR-jev močno spreminja glede na različne vsebine učnega načrta. Delež deskriptorjev, ki učencem omogočajo direktno prepoznavanje SMR-jev, je nizek v vseh vsebinah učnega načrta. Zanimivo je, da deskriptorji, ki ne omogočajo direktne prepoznave SMR-jev, prevladujejo v učbeniških kompletih. Z namenom pridobitve poglobljenega vpogleda v kriterije, na podlagi katerih avtorji učbenikov integrirajo SMR-je z različnimi deskriptorji v učbeniške komplete, so potrebne nadaljnje raziskave. To support the understanding of chemistry concepts and processes at the particulate level, various representations are included in learning materials. This paper focuses on how submicroscopic representations (SMRs) are integrated into Slovenian chemistry textbook sets with respect to the curriculum topics for 8th and 9th Grade. Textbook set analysis is based on four holistic SMRs descriptors (direct, indirect, combined descriptor, and SMRs without descriptors), which support learners’ recognition of SMRs’ informational value at different levels by providing different accompanying SMRs add-ons. The textbook sets analysis revealed that the number of SMRs varies significantly with regard to different curriculum topics. The overall proportion of the descriptors that enable the learner a direct recognition of SMRs is low in all curriculum topics. Interestingly, the descriptors that do not enable the learners a direct recognition of SMRs prevail in textbook sets. To obtain more detailed insight into the criteria based on which the textbook authors integrate SMRs with various descriptors into textbook sets, further studies are necessary.

U ovome radu objašnjen je pojam virtualne stvarnosti. Opisane su primjene te tehnologije kako u prošlosti tako i u 21. stoljeću. Objašnjena je jedna od brojnih podjela videoigara koja u sebi sadrži pojam obrazovna igra, koji veže koncept igrifikacije i učenja baziranog na igrama. Primjena virtualne stvarnosti u obrazovnim igrama pruža mogućnost vizualizacije nevidljivog ili suviše apstraktnog. Implementirana je prototipna obrazovna igra pod nazivom Moleculo za učenje kemije putem tehnologije virtualne stvarnosti. Korišteno je Unity okruženje za jednostavniju izradu. Igra se sastoji od ulazne scene s izbornikom i scene same igre u kojoj se nalaze postaje sa zadanim zadatkom. Svaku postaju potrebno je prijeći u zadanom vremenu spajajući zadanu molekulu i skupljajući bodove. Igra završava kada igrač prijeđe sve postaje. This thesis explains the concept of virtual reality and illustrates its application in the education domain. The application of this technology has been described from the past to the 21st century. One of the many video game divisions has been explained, which includes the concept of an educational game, linking the concept of gamification and game-based learning. The application of virtual reality in educational games provides the possibility of visualization of invisible or too abstract concepts. A prototype educational game called Molecule for learning chemistry has been implemented utilizing virtual reality technology. The Unity environment has been used for easier design. The game consists of an input scene with the main menu and the scene of the game where working stations are located with the default assignment. Each station needs to be crossed in default time by connecting the default molecule and collecting points. The game ends when the player passes all the stations.

The ultimate goal in the understanding of complex chemical processes is a complete description of the underlying reaction mechanism. In the present study and for this purpose, a novel experimental platform is introduced that builds upon electrochemistry capable of generating reactive intermediate species at the electrode surface. The atmospherically relevant nitration of catechols is taken as a case example. First, we confirm the recently proposed nitration mechanism, advancing the understanding of atmospheric brown carbon formation in the dark. We are able to selectively quantify aromatic isomers, which is beyond the limits of conventional electroanalysis. Second, we identify a new pathway of nitrocatechol hydroxylation, which proceeds simply by oxidation and the addition of water. This pathway can be environmentally significant in the dark aqueous-phase formation of secondary organic aerosols. Third, the developed methodology is capable of selectively detecting a wide range of nitroaromatics; a possible application in environmental monitoring is proposed.

Solvent- (SB) and water-borne (WB) fluoropolymer coatings were produced for the outdoor protection of bronze. The coatings were prepared from commercially available resins with alternating fluoroethylene/vinylether copolymers. Because any application of protective coatings on works of art requires that they be removable in accordance with conservation ethics, various approaches to achieve removability of coatings were tested. The influence of modifications was verified through comparisons of hydrophobic, compact and irremovable protective coatings. Consequently, we prepared four types of coatings: two SB coatings and two WB coatings. The first SB coating was designed to have a hydrophobic compact structure (SB-c coating), and the second SB coating was modified with the addition of agents that impart strippability (SB-h coating). The same approach was used for the preparation of the two WB coatings: a compact (WB-c) coating vs. a hydrophilic (WB-h) coating, the latter being prepared through the addition of hydrophilic polyisocyanate. The surface properties of the coatings were compared using scanning electron (SEM) and atomic force (AFM) microscopy. WB coatings were found to be more homogeneous in comparison with SB coatings and to have lower surface roughness. Contact angles confirmed the more hydrophobic nature of SB coatings. Potentiodynamic polarisation measurements and accelerated corrosion tests (exposure to acid vapours) revealed that protection efficiency not only increased with thickness but significantly depended on the coating structure. The structure of coatings depended on the rheological parameters of the formulations simulating their behaviour during storage, deposition, and formation of the dry coating. Combined electrochemical and vibrational spectroscopic experiments were used to simulate long-term outdoor exposure of the protective coatings. Ex situ IR RA spectroelectrochemical measurements showed that hydration was more prevalent with WB coatings, and oxidation of bronze at the interface eventually occurred (656 cm −1 band). WB coatings with more free C O groups were more prone to degradation. In situ Raman spectroelectrochemistry confirmed the better protection efficiency of SB over WB coatings. The optical properties of the coatings on glass showed higher transmittance for WB coatings compared to SB coatings.

Posljednji đerski i prvi pečuški tezarij Josipa Franje Domina, sastavljeni od 25 teza »iz eksperimentalne fizike«, a naslovljeni De corpore generatim, bili su prvi tezariji što ih je Zagrepčanin tiskao nakon što je objavio raspravu Dissertatio physica de aeris factitii genesi, natura, et utilitatibus (1784.), a izlažu jezgru prirodne filozofije u obliku nauka o ustroju tvari, temeljnim silama u prirodi i općim svojstvima tijelā, zatim mehaniku i nauk o gravitaciji te osnove kemije i astronomije. Tiskani u travnju 1785. i 1786. godine, oni označuju prijelomnicu u Dominovim prirodnofilozofskim gledištima. U đerskom tezariju 1785. Domin prvi put poimence spominje Boškovića i prvi put zadaje tezu o kemiji kao znanosti. Prvi spomen Boškovićeva prezimena podudara se s Dominovom transformacijom iz strogoga boškovićevca, kakav je bio u tezarijima od 1778. do 1784. godine, u prirodnoga fillozofa koji se nastoji izboriti za vlastite uvide. Teza o kemiji kao »znanosti podređenoj eksperimentalnoj fizici« svjedoči pak o utjecaju Dominova kompendija o kemiji plinova, ali je i programatski korak naprijed: »najjednostavnija počela« tijela Zagrepčanin naziva molekulama. U pečuškom tezariju 1786. Domin prvi put dodaje tezu o sili inercije, kamenu kušcu tadašnjih prirodnofilozofskih rasprava. Stoga oznaka »iz eksperimentalne fizike« s naslovnice tezarija ne znači da Domin isključuje prirodnu filozofiju iz svojih razmatranja, štoviše, ne znači da Domin prestaje biti filozofom prirode. Upravo obratno, kao »profesor teorijske i eksperimentalne fizike te mehanike kao i poljoprivrede« Domin se suočava s cijelim prirodnofilozofskim nasljeđem epohe, a glavni su mu sugovornici Newton, Bošković i dva boškovićevca: Leopold Biwald u Grazu i Ivan Krstitelj Horvath u Trnavi, Budimu i Pešti. Svoje stavove Domin ponekad oblikuje prema Boškovićevu tumačenju, ponekad s izričitim odmakom od Boškovića, a ponekad se vraća izvornom Newtonu., Two exam thesauri De corpore universim by Josip Franjo Domin, composed of 25 theses in the field of “experimental physics”, the last published in Györ in 1785 and the first published in Pecs in 1786, saw light soon after the printing of his treatise Dissertatio physica de aeris factitii genesi, natura, et utilitatibus (1784), and expounded the core of natural philosophy in the form of a doctrine of the structure of matter, fundamental forces in nature, and general properties of physical bodies, then mechanics and doctrine of gravitation, along with the basis of chemistry and astronomy. Being published in April 1785 and April 1786, they represent a turning­point in Domin’s views in natural philosophy. In the 1785 thesaurus, Domin for the first time mentions Bošković by name, and also for the first time proposes a thesis on chemistry as science. The first mention of Bošković’s surname corresponds with Domin’s transformation from a strict Boscovichian, as confirmed in the the sauri from 1778 to 1784, into a natural philosopher who comes forth with his own insights. The thesis on chemistry as “a science subordinated to experimental physics” is the fruit of Domin’s compendium on the chemistry of gases, yet, at the same time, is a programmatic step forward: Domin refers to “the simplest principles” of the bodies as molecules. In the 1786 thesaurus Domin introduces the thesis on inertia, touchstone of the then discussions in the field of natural philosophy. Therefore, “experimental physics” suggested in the thesauri title does not imply that Domin excluded natural philosophy from his considerations. Quite the reverse: as a “professor of theoretical and experimental physics, mechanics, and agriculture”, Domin is challenged by the legacy of the natural philosophy of the epoch, notably by Newton, Bošković and two Boscovichians – Leopold Biwald in Graz and Ivan Krstitelj Horvath in Tyrnau, Buda and Pest. Thus Domin either tends to mould his views in accordance with Bošković’s natural philosophy, or departs from Bošković or Boscovichians significantly, or shifts towards the natural philosophy of Newton.

The use of rare earth elements is a growing trend in diverse industrial activities, leading to the need for eco-friendly approaches to their efficient recovery and reuse. The aim of this work is the development of an environmentally friendly and competitive technology for the recovery of those elements from wastewater. Kinetic and equilibria batch assays were performed with zeolite, with and without bacterial biofilm, to entrap rare earth ions from aqueous solution. Continuous assays were also performed in column setups. Over 90% removal of lanthanum and cerium was achieved using zeolite as sorbent, with and without biofilm, decreasing to 70% and 80%, respectively, when suspended Bacillus cereus was used. Desorption from the zeolite reached over 60%, regardless of the tested conditions. When in continuous flow in columns, the removal yield was similar for all of the rare earth elements tested. Lanthanum and cerium were the elements most easily removed by all tested sorbents when tested in single- or multi-solute solutions, in batch and column assays. Rare earth removal from wastewater in open setups is possible, as well as their recovery by desorption processes, allowing a continuous mode of operation., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the research project PTDC/AAG-TEC/5269/2014, the strategic funding of UID/BIO/04469/2013 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte, Portugal., info:eu-repo/semantics/publishedVersion

Medpredmetno povezovanje predstavlja ključno sodobno usmeritev razvoja izobraževanja. Ker od učencev vedno bolj pričakujemo sposobnost lateralnega mišljenja, spretnosti in veščine z več področij, je pomembno, da jih učitelji pravilno usmerjamo na poti do medpredmetnega povezovanja pri samem pouku. V diplomskem delu opozarjam na pomembnost medpredmetnega povezovanja in kako lahko medpredmetno povezujemo s pomočjo pojmovnih zemljevidov. V diplomskem delu predstavljamo, v kolikšni meri se povezujejo izbrane vsebine predmetov gospodinjstva in kemije. Za ugotovitev povezav pojmov v posameznih vsebinskih področjih smo s pomočjo potrjenih učbenikov za gospodinjstvo in kemijo za osnovno šolo pripravili pojmovne zemljevide. Pojmovne zemljevide smo naredili v računalniškem programu CmapTools. V njih smo z barvami označili, kako se pojmi med seboj dopolnjujejo in prekrivajo. S pomočjo deskriptivne statistike predstavljamo deleže dopolnjevanja in prekrivanja posameznih pojmov. Ugotovili smo, da se izbrane vsebine iz predmetov gospodinjstva in kemije med seboj prepletajo. Izdelani pojmovni zemljevidi so tako lahko v pomoč učiteljem gospodinjstva in kemije za lažje medpredmetno povezovanje med samim poukom. Interdisciplinary teaching presents a key modern direction towards educational development. Because we are expecting more and more lateral thinking and skills from students, it's important that the teachers guide them to interdisciplinarity. In the dissertation I warn about the importance of interdisciplinarity and how can we do that with the help of conceptual maps. In this dissertation, we present how much of the chosen contents of home economics and chemistry are connected to each other. To figure out the connections of concepts in particular conceptual areas we (with the help of approved textbooks for home economics and chemistry for elementary school) prepared these conceptual maps. We made them in a software called CmapTools. We marked the conceptual maps with colour, based on how the concepts complete and overlap each other. By using descriptive statistics we present the shares of complementing and overlapping of individual concepts. We found that the selected content from home economics and chemistry items is intertwined. Prepared conceptual maps can thus help teachers for easier interdisciplinary teaching during lessons.

Two-component solvent-born polyurethane coatings for the protection of bronze from corrosion were prepared. Trisilanol-heptaisooctyl polyhedral oligomeric silsesquixane (POSS) nanoparticles were exploited to increase the coating protective efficiency. Its improvement was confirmed through a combination of characterisation techniques. In particular, the POSS addition caused an increase of the water contact angle, and an enhancement of the elastic connotation and abrasion resistance of the polyurethane coating. Potentiodynamic polarisation measurements also indicated that the coating containing POSS nanoparticles has an improved protection efficiency. Impedance spectroscopy revealed that the magnitude of low-frequency impedance of polyurethane coatings decreased more for the coating without POSS during exposure in electrolyte for thirty days. Ex situ IR reflection-absorption spectroelectrochemistry was exploited to get insight into the degradation of coatings during chronocoulometric charging at anodic potentials. IR reflection-absorption technique was also used to evaluate any possible effect of different stripper solutions on the bronze substrate.

V današnji informacijski družbi ima informacijsko-komunikacijska tehnologija pomembno vlogo na vseh področjih človekovih dejavnosti. V diplomski nalogi sem želela izpostaviti vidike uporabe informacijsko-komunikacijske tehnologije pri učenju in poučevanju kemijskih vsebin. Informacijsko-komunikacijsko tehnologijo lahko vključimo v poučevanje in učenje različnih kemijskih vsebin, v diplomski nalogi je poseben poudarek na njeni uporabi pri eksperimentalnem delu. Ob didaktični uporabi informacijsko-komunikacijske tehnologije lahko le-ta pripomore k boljšemu razumevanju učnih vsebin. V diplomskem delu sem želela razviti in primerjati eksperimentalne vaje za uporabo pri pouku kemije v osnovni šoli- vsako v dveh izvedbah( z uporabo informacijsko-komunikacijske tehnologije in brez uporabe informacijsko-komunikacijske tehnologije). Pri izvedbi eksperimentalnih vaj z uporabo informacijsko-komunikacijske tehnologije sem uporabila Vernier senzorje za temperaturo, pH in tlak. Za omenjene eksperimentalne vaje v dveh izvedbah sem izdelala učne priprave ter pripadajoče delovne liste. Po mojem mnenju je za primere v diplomski nalogi razvitih eksperimentalnih vaj veliko lažji in učinkovitejši način zbiranja podatkov s pomočjo Vernier senzorjev, ena izmed eksperimentalnih vaj, pa brez uporabe informacijsko-komunikacijske tehnologije sploh ni izvedljiva pri pouku kemije. V prihodnje bi bilo potrebno v diplomski nalogi razvite eksperimentalne vaje preizkusiti in tudi evalvirati z učenci. In today's information society, information and communication technology plays an important role in all areas of human activities. In my graduation thesis, I wanted to highlight aspects of the use of information and communication technology in the teaching and learning of chemical content. Information and communication technology can be involved in the teaching and learning of various chemical contents, and in the diploma thesis is a special emphasis on its use in experimental work. In the case of a didactic use of information communication technology, it can help to better understand the learning content. In the diploma thesis I wanted to develop and compare experimental exercises for use in chemistry in elementary school - each in two versions (using information communication technology and without the use of information and communication technology). In carrying out experimental exercises using information-communication technology, I used Vernier sensors for temperature, pH and pressure. For these experimental exercises in two versions, I have developed teaching methods and the adhesive worksheets. In my opinion, for example, in the thesis of the developed experimental exercises, is a much easier and more efficient way of collecting data with Vernier sensors, and one of the experimental exercises, without the use of information-communication technology is not even practicable in chemistry lessons. In the future, in the diploma thesis, experimental exercises should be tested and evaluated with pupils.

Življenje brez kemije si je v današnjem času težko predstavljati, saj omogoča razumevanje in proučevanje številnih naravnih procesov in pojavov ter nastanka novih materialnih dobrin, ki so del vsakodnevnega življenja. Predmet kemija v osnovni šoli spada med najzahtevnejše naravoslovne vede, saj vsebuje veliko novih in abstraktnih kemijskih pojmov, ki si jih učenci težko predstavljajo in razumejo. Ključ za boljše razumevanje kompleksnih kemijskih vsebin pa je trojna narava kemijskih pojmov, da se lahko pojmi in procesi predstavijo na makroskopski, submikroskopski in simbolni ravni. Največje zanimanje kažejo učenci za makroskopsko raven, saj lahko določene kemijske pojme in procese zaznajo s čutili: vid, sluh, vonj in dotik. Najbolj abstraktna in nezanimiva raven pa je simbolna, saj je treba makroskopska opažanja prevesti v ustrezne simbole, formule oziroma enačbe. Tudi submikroskopska raven se uvršča med abstraktne, saj so makroskopska opažanja razložena na ravni delcev (atom, molekula, ion). Za popolno razumevanje kemije pa ni dovolj razlaga le na eni izmed omenjenih ravni, temveč je treba v proces poučevanja in učenja kemijskih pojmov in procesov sorazmerno vključiti vse tri ravni. V vzgojno-izobraževalnih procesih se za ponazoritev kemijskih pojmov in procesov na ravni delcev uporabljajo submikropredstavitve (SMR), ki predstavljajo analogne modele nekega elementa oziroma spojine. SMR so za učeče na vseh stopnjah izobraževanja ključni dejavnik za učenje in razumevanje kemijske učne vsebine, saj spodbujajo poglobljeno učenje. Pri nepravilni oziroma nedosledni uporabi trojne narave kemijskih pojmov se lahko razvijeta napačno razumevanje in pomanjkljivo znanje kemijskih vsebin. Treba je upoštevati tudi učenčevo predznanje, miselno sposobnost in zahtevnost prehoda med makroskopsko, submikroskopsko in simbolno ravnijo. Nezanemarljivi so tudi učenčeva motivacija, odnos do kemije in zanimanje za učenje trojne narave kemijskih pojmov, ki vplivajo na učenje in uspešnost reševanja nalog v kontekstu. Rezultati dela so pokazali: (1) kje imajo učenci več težav pri branju ali risanju SMR kemijskih reakcij, (2) katere so najpogostejše napake pri risanju SMR kemijskih reakcij, (3) kako učenčev individualni interes, učna samopodoba, zanimanje za učenje trojne narave in kemijskih vsebin vplivajo na njegovo uspešnost reševanja nalog kemijskih reakcij na ravni delcev in (4) ali na uspešnost reševanja nalog vpliva uporaba submikroprezentacij pri pouku kemije. Raziskava je potekala na šestih osnovnih šolah v različnih regijah Slovenije. Sodelovalo je 250 osnovnošolcev, ki so v šolskem letu 2017/18 zaključevali deveti razred osnovne šole, in njihovi učitelji kemije. Rezultati so smiselno podani po sklopih. Ugotovljeno je bilo, da imajo naši osnovnošolci več težav pri risanju kot pri branju SMR kemijskih reakcij, ker pri risanju ne upoštevajo ustreznih veljavnih kemijskih pravil in zakonov. Največ težav pa imajo pri upoštevanju velikosti narisanih delcev, agregatnem stanju kovin, kovinskih oksidov in vodne raztopine soli ter pri upoštevanju stehiometričnega razmerja posameznih elementov na strani reaktantov in produktov. Rezultati kažejo tudi, da imajo učenci težave pri prepoznavanju dvoatomnih molekul, saj so vodik in kisik risali v obliki atomov, ter pri poimenovanju in zapisovanju simbola in molekulske formule. Ugotovljeno je bilo, da so učenci, ki jih bolj zanima učenje kemije, uspešnejši pri reševanju nalog, ki temeljijo na branju in risanju SMR kemijskih reakcij. Na to pa vpliva tudi uporaba submikroprezentacij pri pouku. Učenci, katerih učitelji v pouk kemije pogosteje vključujejo sheme delcev, so uspešnejši pri reševanju tovrstnih nalog. Zbrani podatki kažejo, da ima pri poučevanju in razumevanju kemijskih reakcij na ravni delcev pomembno vlogo učitelj, ki načrtuje pouk. Če učitelj kemijske pojme pogosteje obravnava na treh ravneh ter oblikuje naloge, s katerimi učenci utrdijo in ponovijo usvojeno učno vsebino, učenci bolje razumejo kemijske vsebine in je manj možnosti za razvoj napačnega razumevanja. Life without chemistry is difficult to imagine in today's world. Chemistry enables understanding and research of numerous natural phenomena and the emergence of new consumer goods which are part of everyday life. Chemistry at primary school is one of the most challenging natural sciences because it includes many new and abstract scientific concepts which students find difficult to conceive and comprehend. The key to better understanding of the complex chemistry contents is to appreciate the triple nature of the concepts in order to present chemistry notions and concepts on the macroscopic, sub-microscopic, and symbolic levels. Students gravitate to the macroscopic level the most because they can perceive certain chemistry notions and concepts with their visual, auditory, olfactory, and tactile senses. The most abstract and uninteresting aspect of chemistry for them is the symbolic domain where the macroscopic observations have to be translated into suitable symbols, formulas, or equations. The sub-microscopic level is a part of the abstract domain as well because the macroscopic observations are explained at the level of particles (atom, molecule, ion). However, for a complete understanding of chemistry it does not suffice to offer an explanation based just on one of the domains identified. All three domains must be equally integrated into the process of teaching and the study of chemistry notions and concepts. Schools use sub-micropresentations (SMR) which show analogue models of a particular chemical element or substance to illustrate these notions and concepts in the domain of particulates. The SMR presentations are the key factor in studying and understanding the chemistry syllabus for students at all levels of education because they stimulate in-depth learning. Incorrect or inconsistent use of the triple nature of chemical concepts can lead to misconceptions and deficient knowledge of the chemistry syllabus. Good instruction needs to consider student's previous knowledge, his or her mental ability and the complexity of the transition between the macroscopic, sub-microscopic, and symbolic domains. Other factors, which should not be ignored, are a student's motivation, his or her attitude towards chemistry and interest in studying the triple nature of the chemistry concepts. These factors influence the concepts of learning and affect the student's success in solving the tasks in a particular context. The results of this master thesis show the following: (1) the domains where students have more difficulties in reading or drawing the SMR of chemical reactions (2) the most common misconceptions which occur in drawing chemical reactions at the sub-microscopic level (3) how a student's attitude towards chemistry affects his or her success in solving chemical reaction tasks at the level of particulates and (4) whether the use of sub-micropresentations in chemistry lessons influences the success in solving chemistry tasks. The survey was conducted at six primary schools in different areas of Slovenia. It included 250 primary school students who were finishing the 9th grade of primary school in 2017/2018 and their chemistry teachers. The results of the survey are systematically presented in several topical sets. The results show that Slovenian primary school students have more difficulties in drawing the SMR of a chemical reactions than in reading them because they do not follow the relevant rules and laws of chemistry. Students experience the major share of difficulties in considering the size of the particles they have to draw, determining the aggregate state of metals, metal oxides, and aqueous solutions of salts. Students also find it difficult to consider the stoichiometric relationship between the individual elements of reactants and products. In addition, this research effort reveals that recognizing diatomic molecules poses another problem for students. They would draw the hydrogen and oxygen gases in the form of atoms. Another difficult issue is the naming and writing of a symbol and a molecule formula. The results of the thesis show that students with a greater individual interest in studying chemistry are more successful in solving the tasks, which are based on reading and drawing the SMR of chemical reactions. The level of students' success is affected by the use of sub-micropresentations in chemistry lessons. The students whose teachers often include schematics of particulates in their chemistry lessons are more successful in solving such tasks. The data collected reveals that a teacher's way of a lesson planning results in his or her teaching style and the students' understanding of chemistry reactions at the level of particulates. If a teacher frequently discusses chemistry concepts at each of the three concept domains and prepares tasks, which reinforce and revise the learning of the content, the students understand the chemistry syllabus better and misconceptions are less likely to develop.

Učni načrt za kemijo v osnovni šoli vključuje uporabo eksperimentalnega dela za doseganje standardov znanja, vezanih na učne cilje. Učni načrt prav tako predvideva učno diferenciacijo in individualizacijo v fazah načrtovanja in izvedbe pouka ter tudi pri preverjanju in ocenjevanju znanja (Bačnik idr., 2011). V slovenskem prostoru je primanjkljaj raziskav na področju učne diferenciacije in individualizacije kemijskega eksperimentalnega dela v šolski praksi, zato je ta tema obravnavana v magistrski nalogi. V teoretičnem delu magistrskega dela je predstavljena literatura na temo eksperimentalnega dela pri pouku kemije ter učne diferenciacije in individualizacije. V empiričnem delu magistrskega dela je razvita metodologija za učiteljevo spremljanje napredka učencev med kemijskim eksperimentalnim delom, upoštevajoč učno diferenciacijo in individualizacijo (UDKED). V raziskavo je bilo vključenih 45 učencev osmega razreda. Na osnovi uporabe vprašalnikov UDKED na celotnem vzorcu 45 učencev s strani dveh učiteljev, ki vsaj 6 mesecev strnjeno poučujeta učence pri predmetih, ki temeljijo na eksperimentalnem delu učencev in njihovih analizah, so bile sestavljene skupine učencev za učno diferenciacijo in individualizacijo. Učna enota s področja kemijskih vsebin za uresničevanje učne diferenciacije in individualizacije pri učencih je bila razvita v sodelovanju z učiteljico kemije in specialno pedagoginjo iz izbrane osnovne šole, ter bila uporabljena na naravoslovnem dnevu. Naravoslovni dan ob uporabi učne enote je izvedla učiteljica kemije. V enem tednu po izvedbi naravoslovnega dne je učiteljica odgovorila na vprašanja strukturiranega intervjuja. Osnova za izdelavo magistrske nalogo so bili analizirani delovni listi iz naravoslovnega dneva s kemijskim eksperimentalnim delom, upoštevajoč učno diferenciacijo in individualizacijo ter odgovori strukturiranega intervjuja z učiteljico. Rezultati kažejo na raznolikosti med učenci pri usvajanju znanja ob uporabi eksperimentalnega dela tudi znotraj skupin učencev prve in druge skupine ter ne omogočajo izpeljave sklepov glede uspešnosti reševanja nalog I., II. in III. taksonomske stopnje. Prav tako ne omogočajo zapisa opažanj in sklepov za celotne skupine, pač pa lahko iz zapisov sklepov na primeru treh izbranih učencev sklepamo, da učna enota omogoča usvajanje znanj izbranim učencem tretje skupine. V prihodnosti bi bilo mogoče raziskavo še nadgraditi, predvsem bi bilo potrebno izvesti raziskavo na več kot treh eksperimentalnih vajah, za ocenjevanje napredka pa bi bilo potrebno uporabiti anketni vprašalnik UDKED. Raziskavo bi bilo smiselno nadaljevati z večjim vzorcem učencev iz različnih šol, ki bi jih spremljali skozi daljše obdobje, in z vključitvijo več učiteljev v intervju. The curriculum for chemistry in the elementary school includes the use of experimental work for achieving the standards of knowledge, connected with the learning objectives. The curriculum also anticipates learning differentiation and individualization in the phases of planning and performing the school lessons and also in the assessment of knowledge (Bačnik et al., 2011). In the Slovenian space, there is the lack of research in the field of learning differentiation and individualization of the chemical experimental part in the school practice. Therefore, this topic is discussed in the master’s thesis. In the theoretical part of the master’s thesis, the literature on the topic of the experimental part within the school lessons of chemistry, learning differentiation, and individualization is presented. In the empirical part of the master’s thesis, the methodology for the teacher’s following the progress of students between the chemical experimental part is developed with respect to the learning differentiation and individualization (UDKED). 45 students of the eighth grade were included in the research. On the basis of the use of the questionnaires UDKED in the entire sample of the 45 students by a couple of teachers who teach the students continuously for at least six months within the subjects which are based on the experimental work of the students and their analyses, the groups of students were composed for learning differentiation and individualization. The learning unit from the field of chemical contents for the realization of the learning differentiation and individualization in students was developed in cooperation with the teacher of chemistry and a special teacher from the selected elementary school and was engaged during a natural science day. The teacher of chemistry performed the natural science day by the use of the learning unit. The teacher answered the questions of the structured interview in a week after the performance of the natural science day. The basis for the production of the master’s thesis was the analyzed worksheets from the natural science day with chemical experimental work considering the learning differentiation and individualization and the answers of the structured interview with the teacher. The results show the varieties between the students in assimilating knowledge within the use of experimental work also within the groups of the first and the second group and do not enable carrying out the resolutions considering the successfulness of performing the tasks of the 1st, 2nd, and the 3rd group of the taxonomic rate. They also do not enable the recording of observations and resolutions for the whole groups. We can conclude on the basis of the recordings of the resolution, however, that the learning unit enables the assimilation of knowledge to the selected students of the third group. In the future, it would be possible perhaps to upgrade the research even more. Mostly, a research would have to be performed in more than three experimental exercises. In order to evaluate the progress, the survey questionnaire UDKED would have to be used. It would make sense to continue the research with a larger sample of the students from different schools who would be followed for a longer period of time and by including a larger number of teachers in the interview.

Namen diplomskega dela je razviti kriterije za analizo pisnih preizkusov znanja pri kemiji, s katerim bi lahko pisne preizkuse znanja pri kemiji naredili kakovostnejše. Prav tako bi bili kriteriji lahko v veliko pomoč učiteljem začetnikom pri sestavljanju pisnih preizkusov znanja. Pouk kemije temelji na eksperimentalnem delu, razvoju odnosa do okolja, na opazovanju in opisovanju videnih in tudi abstraktnih pojavov. Glede na kompleksno sestavo pouka kemije je izrednega pomena, da je pisni preizkus kakovosten ter tudi strokovno neoporečen. Glavna značilnost kakovostnega ocenjevanja je, da je to usklajeno z obravnavano učno vsebino in s cilji učnega načrta. Pisni preizkus znanja nazorno prikaže, kaj učitelj v vlogi njegovega sestavljavca pojmuje kot znanje. Je najpogostejša oblika preverjanja in ocenjevanja znanja na vseh treh vertikalah vzgojno-izobraževalnega sistema. V prvem delu diplomskega dela je predstavljeno teoretično ozadje preverjanja in ocenjevanja znanja ter njihovih lastnosti, predstavljeni so različni tipi nalog, pisni preizkus znanja ter merske karakteristike. V nadaljevanju sledijo merila za analizo pisnih preizkusov znanja kemije. The purpose of my diploma thesis is to develop the criteria for analytical methods of assessing the level of chemistry knowledge in order to improve the quality of the written tests in chemistry. Such criteria could also be an invaluable asset to the beginner teachers when they make tests. Chemistry classes are based on experimental work, developing relationship with the environment, observing and describing the visual and abstract phenomena. Due to the complex structure of chemistry lessons it is of utmost importance for the tests to be of high quality and professionally indisputable. The main characteristic of qualitative assessment is the alignment with the learning content and the goals of the curriculum. The content of examination clearly shows what is considered to be proper knowledge by the teacher who made the test. It is the most common form of evaluating and assessing knowledge on the all three verticals of the educational system. The theoretical background of evaluating and assessing knowledge, the properties, different types of examination tasks, a written test, and measure characteristics are presented in the first part of the diploma thesis.

Svoje magistrsko delo sem razdelila na eksperimentalni in pedagoški del. V eksperimentalnem delu sem pripravila različne koordinacijske spojine bakra(II) s kinaldinatom. Moj cilj je bil, da bi spojine poleg kinaldinata vsebovale še sekundarni piridinski ligand: 4-hidroksipiridin, 3-hidroksipiridin ali 3-hidroksimetilpiridin. V pedagoškem delu sem predstavila učno uro z eksperimentalnim delom, vzgojo kristalov bakrovega(II) acetata hidrata. Na začetku učne ure so učenci ponovili učno snov o kristalih. Učno uro sem umestila v učni načrt kemije za osnovno šolo. Priložen je tudi delovni list za učitelja in učenca. I divided my master's thesis into experimental and pedagogical work. In the experimental work, I prepared various coordination compounds of copper(II) with quinaldinate. Main goal was that the complexes contained in addition to quinaldinate also a secondary pyiridine ligand:4-hydroxypyridine, 3-hydroxypyridine or 3-hydroxymethylpyridine. In the pedagogical work, I introduced a teaching lesson which included experimental work on the preparation of large crystals of copper(II) acetate hydrate. At the beginning of the lesson, the pupils reiterated the learning material about the crystals. The lesson is incorporated into a chemistry curriculum for elementary school. A worksheet for the teacher, as well as for the student is attached.

Namen magistrskega dela je raziskati vse možne načine razmišljanja, razumevanja in povezovanja pojmov šolarjev v osnovnih šolah glede uporabe znanj o grafih pri kemiji. Z raziskavo želimo ugotoviti, ali učenci uspešno prenesejo znanje, povezano z grafi funkcij, in ali znajo stroge matematične definicije uspešno uporabiti pri kemijskih ter realnih življenjskih primerih. Metoda, ki je bila uporabljena pri raziskavi, je fenomenografija z intervjujem ob pisnem reševanju nalog, kjer je sodelovalo 30 učencev devetih razredov osnovnih šol iz šestih različnih oddelkov. Končna analiza je pokazala, da lahko rezultate razvrstimo v matematični in naravoslovni sklop. Pri matematičnem sklopu je šlo za sedem kategorij znanja z več podkategorijami, prav tako smo tudi pri naravoslovnem oziroma kemijskem sklopu uporabili sedem kategorij s podkategorijami. Učenci so bili tako pri enostavnejših primerih uspešni v približno 50-odstotkih. Težji primeri, po Gagneju problemskega znanja, pa učencem povzročajo nekaj več težav in je razumevanje zato slabše. Pri raziskavi smo naleteli na neskladje v učnih načrtih glede vpeljave termina neodvisne in odvisne spremenljivke, ki ga predstavimo in priporočamo, da se čimprej odpravi. Po odpravi neskladja bodo učitelji naravoslovnih in kemijskih vsebin imeli na področju grafov lažje delo, saj bodo učenci to znanje prenesli iz matematičnega področja in ga pri kemiji nadgradili. Učiteljem priporočamo, naj namenijo več pozornosti razumevanju grafov ne le izrisu in uporabi grafov kot ilustracij. The purpose of the master's thesis is to explore all possible ways of thinking, understanding and connecting the concepts of schoolchildren in elementary schools regarding the use of knowledge about charts. We want to find out whether students successfully transfer knowledge related to charts of functions and whether they can successfully apply strict mathematical definitions into chemical and real-life examples. The method used in the research was phenomenography with an interview during written task solving, involving 30 pupils from the ninth grade of elementary schools from six different school classes. The final analysis showed that the results can be classified into mathematical and natural sciences. There were seven categories of knowledge with several subcategories in the mathematical framework, as well as seven categories with subcategories in natural sciences and chemistry. The success rate of pupils solving simpler tasks was approximately 50%. More difficult tasks, problem-knowledge by Gagne, give students a little more difficulty and consequently understanding is worse. In the study, we encountered incompatibilities in the curriculum regarding the introduction of the terms independent and dependent variable, which we highlighted and recommend removing as soon as possible. After resolving the incompatibilities, science and chemistry teachers will have an easier job in the field of charts, since students will transfer this knowledge from the mathematical field and upgrade it in chemistry. Teachers are encouraged to focus the attention on understanding charts, rather than drawing and using charts as an illustration.

Adsorpcijo si lahko razlagamo podobno kot površinsko napetost. Zunanji delci snovi imajo na voljo manj sosednjih delcev za povezovanje kot delci v notranjosti, zato se pri površinski napetosti močneje povežejo med seboj. Pri adsorpciji pa izkoristijo to pomanjkanje možnosti povezovanja tako, da pritegnejo na svojo površino druge snovi iz okolice. Tako se površina adsorbenta prekrije s plastjo druge snovi in jo zato izloči iz okolice. Ta okolica adsorbenta je lahko raztopina ali pa plinska zmes.

Kemiluminiscenca, ena izmed vrst luminiscence, je sevanje svetlobe značilnih valovnih dolžin kot posledica eksotermne kemijske reakcije. Ta poteka znotraj svetlečih palčk, ki jih lahko uporabimo pri poučevanju fizikalnih in kemijskih učnih vsebin v osnovni in srednji šoli, da z njimi učencem vizualiziramo težje razumljive pojme in tako povečamo notranjo motivacijo za učenje naravoslovja. V magistrskem delu bom razvila eksperimente s svetlečimi palčkami primerne za uporabo pri pouku, s katerimi dosežemo čim več ciljev učnega načrta za fiziko in kemijo v osnovni šoli in splošni gimnaziji. Z njimi želim učence navdušiti za naravoslovje ter izboljšati njihovo razumevanje. Ker so svetleče palčke učencem poznane iz vsakdanjega življenja, so zanimiv pripomoček za eksperimentiranje v šoli, zato zagotovo sodijo k sodobnem pristopu poučevanja naravoslovja. In my master thesis I present theoretical and practical aspects of chemiluminescence in glow sticks. Chemiluminescence is one of many types of luminescence and means radiation of light of characteristic wavelengths as a result of exothermic chemical reaction. This process takes place inside of glow sticks and can be used in physics or chemistry classes in primary and in secondary school. With glow sticks (that radiate different colours) we can easily visualize difficult-to-understand concepts to students and we can also increase student's motivation for studying natural sciences. The theoretical part describes the concepts important for understanding luminescence processes, the chemiluminescence reaction mechanism in glow stick, the analogy with the functioning principle of lasers and also the advantages and benefits of student's independent experimental work with glow sticks. In the experimental part, there are 5 optimized experiments with glow sticks which can be used in classes. With experiments we can achieve many objectives of the curriculum in physics and chemistry in primary and secondary school. The experiments are: a) Proof that hydrogen peroxide is a reagent in the reaction in a glow stick, b) Determining which substance is formed in the reaction in a glow stick, c) Anayisis of the influence of base and acid on the emission of light, d) Determining whether the energy is released or absorbed during the reaction in a glow stick, e) Display of additive light mixing. Each experiment is also equipped with a worksheet for students and the teacher.

V magistrskem delu je predstavljena raziskava o razumevanju agregatnih stanj vode in prehodov med njimi učencev sedmega razreda, dijakov prvih letnikov gimnazije in študentov Pedagoške fakultete Univerze v Ljubljani. V teoretičnem delu sta opisana trojna narava kemijskih pojmov in učenje kemije na treh ravneh kemijskega pojma, kjer sta predstavljena primer rastočega trikotnika in model dvigajoče se ledene gore. V nadaljevanju teoretičnega dela sta opisana procesiranje informacij in pomen vizualizacije pri tem. Predstavljena je uporaba očesnega sledilca pri spremljanju kognitivnih procesov pri naravoslovnem izobraževanju. Podane so raziskave na področju napačnih razumevanj agregatnih stanj in prehodov med njimi. Glavni namen magistrskega dela je bil ugotoviti razumevanje kemijskih pojmov, povezanih z agregatnimi stanji vode, na makroskopski in submikroskopski ravni, prehodov med agregatnimi stanji na submikroskopski ravni ter primerjati rezultate reševanja izbranih avtentično zasnovanih nalog učencev sedmega razreda osnovne šole, dijakov prvega letnika gimnazije in študentov kemije z vezavami Pedagoške fakultete. V raziskavi je sodelovalo 31 učencev, 29 dijakov in 20 študentov. Rezultati analize reševanja avtentičnih nalog so interpretirani z meritvami, dobljenimi z očesnim sledilcem, s katerim se lahko spremljajo kognitivni procesi pri reševanju. Vsi testiranci so pravilno prepoznali submikroskopske predstavitve trdnega, tekočega in plinastega agregatnega stanja na ravni delcev. Težave pa so imeli pri utemeljevanju svoje izbire. Iz rezultatov raziskave je mogoče sklepati o napačnih razumevanjih pri razlagi makroskopskih ugotovitev na submikroskopski ravni. Testiranci so imeli tudi težave pri razumevanju prehodov med agregatnimi stanji pri procesu nastajanja slane, saj jih je manj kot polovica podala pravilen odgovor. Rezultati očesnega sledilca so pokazali, da so uspešnejši učenci, dijaki in študenti imeli daljši povprečni skupni čas in večje povprečno število fiksacij na 3D-animaciji nastajanja slane kot na slikah kot pa neuspešni. Rezultate raziskave lahko povežemo z ugotovitvami drugih raziskav, ki so pokazale podobna napačna razumevanja. Ugotovitve raziskave lahko vplivajo na pristope pri poučevanju, s katerimi je mogoče preprečiti in odpraviti napačna razumevanja. The master's thesis presents a study on the understanding of states of matter and the transitions between them by pupils of the seventh grade, students of the first year in gymnasiums (high school) and students at the Faculty of Education. The theoretical part describes the triple nature of chemical concepts and teaching chemistry on the three levels of a chemical concept, where the example of the expanding triangle and the rising iceberg model are presented. In the continuation of the theoretical part, the process of information processing is described and the significance of visualisation. The use of an eye tracker in the monitoring of cognitive processes in natural sciences teaching is described. Studies on the misconception of states of matter and transitions between them are also presented. The main aim of master's thesis was to determine the understanding of chemical concepts that relate to states of water on macroscopic and submicroscopic levels, the transitions between states on a submicroscopic level, and to compare the results of select original exercises devised for pupils of the seventh grade, students of the first year in gymnasiums (high school) and chemistry students at the Faculty of Education. The study included 31 pupils, 29 high-school students and 20 university students. The results of the analysis where original exercises were completed were then interpreted using measurements obtained using an eye tracker that made it possible to track the cognitive processes used when solving the exercises. All test participants correctly recognised the submicroscopic presentation of the solid, liquid and gas physical states on a particle level. However, they did experience problems when justifying their decision. From the study results it is possible to conclude that there were problems understanding the explanation of macroscopic findings on a submicroscopic level. The test participants also had problems with the transitions between states in the frost formation process, since less than half responded with the correct answer. The results of the eye tracker showed that the more successful pupils, high-school and university students had a greater average total time and average number of fixations on the 3D animations of how frost formed in comparison with the pictures, compared to the less successful participants. The study results can be linked to findings from other studies that showed similar misconceptions. The study findings can affect the approaches used when teaching to avoid and eliminate misconceptions.

Preverjanje in ocenjevanje znanja nas spremljata na vsakem koraku šolanja. Učencem in staršem tako predstavljata pomembne informacije o znanju in napredovanju učencev. Učitelji preko preverjanja in ocenjevanja poleg vpogleda v znanje učencev, dobijo še vpogled v to, kako uspešni so pri doseganju učnih ciljev učnega načrta, posameznih učnih enot in predmeta. Pomemben vir informacij za učitelje so tudi zunanja preverjanja znanja. Področje naravoslovja oziroma kemije so v obdobju od leta 1995 do 2015 pokrivala tri zunanja preverjanja znanja: NPZ (Nacionalno preverjanje znanja), PISA (Programme for International Student Assessment) in TIMSS (Trends in International Mathematics and Science Study). TIMSS preverja učne cilje, ki so skupni vsem državam, v katerih se raziskava izvaja, PISA pa temelji na preverjanju in aplikaciji znanja na življenjske situacije. Glavni cilji diplomskega dela so bili ugotoviti, ali učitelji kemije na slovenskih osnovnih šolah poznajo ključne cilje NPZ, TIMSS in PISA, ali v njih prepoznavajo uporabno vrednost za lastno šolsko prakso pouka kemije, ter pridobiti predloge učiteljev kemije, kako izpopolniti tovrstne preizkuse znanja, da bi učitelji kemije v njih videli večjo uporabno vrednost. V teoretičnem delu naloge so predstavljene osnovne informacije o preverjanju in ocenjevanju v osnovni šoli, ključni cilji NPZ, TIMSS in PISA, ter kratek pregled zagotavljanja kakovosti na področju zunanjih preverjanj znanja v Evropi. V empiričnem delu naloge so zbrani podatki, ki so bili statistično obdelani v programu Excel. Rezultati empiričnega dela kažejo, da učitelji kemije najbolje poznajo cilje NPZ, sledijo cilji TIMSS, slabše pa poznajo cilje raziskave PISA. Rezultati kažejo tudi, da večina vprašanih učiteljev kemije, svojih učencev ne pripravlja dodatno na zunanja preverjanja znanja iz kemije, kot pomembno uporabno vrednost tovrstnih preverjanj znanja pa učitelji izpostavljajo nove tipe nalog, ki se pojavljajo. Knowledge assessment and grading is part of every stage of education. Through such activities, learners and parents receive relevant information about learner's knowledge and improvement. On the other hand, teachers seize through knowledge assessment and grading information how successful they are in fulfilling learning objectives of the curriculum, specific learning units and of the subject itself. An important source of information for teachers are as well external examinations. Subjects of natural sciences (or chemistry, to be specific) were from 1995 to 2015 examined by the three external knowledge assessments: NPZ (National Assessment of Knowledge), PISA (Programme for International Student Assessment) and TIMSS (Trends in International Mathematics and Science Study). TIMSS assesses learning objectives that are the same in every country, where the survey is carried out, while PISA focuses on assessment and application of knowledge in real life situations. The main goals of my diploma paper were to discuss if chemistry teachers in Slovene primary schools are acquainted with the key objectives of NPZ, TIMSS and PISA, if they recognize the applicative value for their own teaching and to collect suggestions from chemistry teachers how to improve such knowledge assessments, so teachers would recognize them as important and useful. In the theoretical part of my diploma paper, I introduced general information about knowledge assessment and grading in primary school, key objectives of NPZ, TIMSS and PISA and a short review of quality assurance of external knowledge assessment in Europe. Data presented in the empirical part of the paper were analysed with Excel. The results show that chemistry teachers are best acquainted with goals related to NPZ, followed by TIMSS, while their knowledge about PISA survey’s goals is weaker. Results show that the majority of teachers included in my research do not additionally prepare their learners for the external knowledge assessment from chemistry. In their opinion, the important applicative value of such knowledge assessments are the new types of tasks that occur.

V zadnjem desetletju se je kot odziv na okoljsko problematiko, povezano s plastiko, na tržišču pojavilo veliko novih bioplastičnih materialov, s katerimi se učenci srečujejo v vsakodnevnem življenju, zato je pomembno, da jih poznajo. V teoretičnem delu magistrskega dela so predstavljena teoretična izhodišča o polimerih, s posebnim poudarkom na bioplastiki, ter o aktivnem pouku naravoslovnih vsebin. Rezultati, ki so bili pridobljeni v raziskavi, so predstavljeni v empiričnem delu magistrskega dela. Raziskava je bila izvedena z namenom pridobitve podatkov o trajnosti in kakovosti znanja, usvojenega z aktivnim poukom, ter spodbuditi situacijski interes učencev za usvajanje znanja o bioplastiki pri pouku kemije v 9. razredu osnovne šole. V raziskavo je bilo vključenih 197 učencev, ki so s samostojnim delom usvajali znanje s področja o bioplastiki. Kontrolna skupina je znanje o bioplastiki usvajala s pomočjo poljudnega članka po korakih splošne učne strategije, medtem ko je eksperimentalna skupina znanje usvajala s pomočjo samostojnega eksperimentalnega dela po navodilih. Kontrolna in eksperimentalna skupina sta bili oblikovani tako, da med njima na predpreizkusu znanja ni bilo statistično pomembnih razlik. Po izvedenih učnih urah so učenci eksperimentalne in kontrolne skupine najprej rešili preizkus znanja in vprašalnik glede situacijskega interesa za usvajanje znanja o bioplastiki. Tri tedne zatem so učenci obeh skupin rešili še pozni preizkus znanja. Rezultati, ki so bili pridobljeni v raziskavi, so pokazali, da učenci eksperimentalne skupine v trajnosti in kakovosti usvojenega znanja ne dosegajo statistično pomembno boljših rezultatov od svojih sovrstnikov iz kontrolne skupine. Prav tako tudi glede na spol med dekleti in fanti na preizkusu in poznem preizkusu znanja ni bilo statistično pomembnih razlik v usvojenem znanju. Pri situacijskem interesu za usvajanje novih vsebin o bioplastiki je mogoče trditi, da med učenci eksperimentalne in kontrolne skupine ni bilo razlik, saj nobena skupina ni pokazala večjega interesa za usvajanje znanj na temo bioplastike. Tudi za situacijski interes, gledano po spolu, ne moremo trditi, da so fantje pokazali višji situacijski interes za usvajanje novih znanj o bioplastiki. Povzamemo lahko, da v povezavi s proučevanimi dejavniki med obravnavanima pristopoma v raziskavi ni bilo ugotovljenih razlik glede primernosti za uporabo pri poučevanju vsebin o bioplastiki. V nadaljnjih raziskavah bi bilo mogoče razširiti vzorec sodelujočih tako, da bi vključili učence iz celotne Slovenije, raziskavo prilagoditi za populacijo dijakov, prav tako bi bilo zanimivo proučiti druge možnosti za aktivni pouk o bioplastiki ter pridobiti mnenje in izkušnje učiteljev kemije o poučevanju vsebin, povezanih z bioplastiko. In the last decade many new bioplastic materials have appeared as a response to environmental issues related to the plastics on the market, so it is important for children to know them, because they are encountering them daily. In theoretical part of a dissertation is at first being introduced a theoretical basis about polymers with the emphasis on bioplastic and active learning about natural contents. Results, which were extracted during the research are shown in empirical work of my dissertation. A research was carried out with a purpose to get data about constancy, quality of knowledge considering active teaching methods and situational interest of pupils about gaining knowledge of bioplastic in the chemistry class in ninth grade of primary school. In the research were included 197 children, who formed a new knowledges from the field of bioplastic with their own work. The control group was gaining new knowledges about bioplastic step by step using general learning strategies with the help of an non-technical article, while experimental group was gaining knowledge with their independent experimental work using given instructions. Control and experimental group were formed in the way that there were no big statistical differences on the pre-test. Pupils had solved a test and a questionary after the lessons were carried out, with which we checked their situational interest about gaining knowledge of bioplastic. Three weeks after that the children of both groups solved late test of their knowledge. Results, which were extracted during the research showed that children of experimental group don’t achieve any better results about constancy and quality of knowledge compared to control group. Also considering the gender, there were no statistical significant differences in their gained knowledge. In situational interest for gaining new knowledge about bioplastic we can claim that there were no differences between control and experimental group, because none of them showed bigger interest in gaining new knowledge about bioplastic. Even for the situational interest considering the gender we can’t claim, that boys showed bigger situational interest in gaining new knowledges about bioplastic. To sum up, we can say that there were not established big differences in relation to studied factors between discussed approaches and both of them are equally suitable in teaching about bioplastic. In further researches we could expand pattern of participants with including children from all Slovenian schools or we could adjust our research for population of students. In addition, it would be also interesting to study other possibilities for active teaching about bioplastic and get an opinion and experiences from teachers of chemistry about teaching contents connected with bioplastic.

Razumevanje gorenja je precej povezano tudi z razvojem pojma toplota. Kar nekaj raziskav dokazuje, da otroci razumevajo toploto kot snov, zato toplota prispeva k masi snovi, ki jo segrevamo. Skoraj polovica vprašanih učencev je odgovorila, da je kos vročega bakra težji od hladnega bakra.

Chemical models are indispensable tool in chemistry class and enable secondary school pupils to develop complex thought processes and spatial concepts, both of which are necessary to improve their understanding of chemical concepts. In this research, special emphasis is given to complex competencies not only their acquisition, but rather how pupils develop them. For this purpose, a learning strategy has been developed, called learning by self-generating chemical models. Pupils learn individually on their own models, which are made from easily accessible, low-cost materials. The impact of workable models was investigated (assembly of commercial models and production of self-made models) on the (1) learning success using simple molecule shapes and (2) the degree of competence development which realized through the implemented activities. The study involved first-year secondary school-pupils, defined as self-creators of paper- and -wire models (experimental group) and assemblers of commercial models (called the control group). The appearance of the molecules being studied took the form of geometric shapes and structures, which pupils present by making of ball-, called wire-models from plasticine and wire or paper created, called paper models. Based on the results of statistical processing of the data, we found that self-creation of models (as an innovative approach) leads to better understanding and to subsequently sustained knowledge for the pupil. It should also be noted that pupils who were self-generators in comparisons to those who merely assembled the models, generally developed many complex skills in the areas of problem solving, practical competence, mathematical competence and critical thinking skills. The knowledge so acquired was also better understood.

The main aim of the teacher study program is to ensure the proper role of teaching practice, which is included in initial teacher training courses. It is necessary that teachers of chemistry gain or develop learner competencies for appropriate teaching/ learning in the chemistry subject by using innovative teaching methods. In terms of activities and methods correction of the continuous teaching practice model for prospective chemistry teachers in Pedagogical study program of 2nd degree "Educational Chemistry" which would ensure the creation of a competent chemistry teacher (active and innovative). The main result of the study is a list of potential competencies by prospective chemistry teachers using innovative teaching methods. These competencies can be developed and produced in the performance of activities defined by using continuous teaching practice, particularly in the areas of testing and assessment, experiential and collaborative learning, and experimental (laboratory and field) work. Each of these components is separately assessed by activity and competence.

Learning in the information age is characterised by abundant prolif- eration of information from various sources that are communicated to the learners by a variety of means, which are usually supported by information- communication technology (ICT), such as the internet, social media, virtual classrooms, etc. However, the textbook sets continue to have the central role in supporting effective teaching and learning of science as they should be, by their intent, synchronised with national curriculum for specific subject at certain educational levels. They are used for studying at school as well as at home (Gkitzia, Salta & Tzougraki, 2011). Therefore, significant attention has been paid to textbook analysis in science education. For example, Devetak, Vogrinc, and Glažar (2010) studied explanations of states of matter in Slove - nian science textbooks; Majidi and Mantyla (2011) studied the knowledge organisation in magnetostatics in Finnish textbooks; Lacin-Simsek (2011) studied female scientists in Turkish science and technology textbooks; Mumba, Chabalengula, and Hunter (2007) studied inquiry levels and skills in Zambian high school chemistry textbooks.

Kot druge države Evropske unije se tudi Slovenija sooča z izzivom priseljevanja. Priseljenci so ob vključitvi v novo kulturno okolje deležni težav, največkrat povezanih z nerazumevanjem novega jezika in nepoznavanjem kulturnih in družbenih praks. Koncept inkluzivnega izobraževanja vključuje načelo medkulturnosti in zahteva sistematično delo vseh vključenih v šolsko okolje. Učitelji se vsakodnevno srečujejo z izzivi, povezanimi z razumevanjem jezika in drugačnimi kulturami, poznati pa morajo tudi procese integracije priseljencev in prilagajanja na novo kulturno okolje. Učitelji so odgovorni za pripravo razreda, upravljanje v razredu, kot tudi v razvoju učencev. V magistrski nalogi predstavljamo najpogostejše izkušnje, s katerimi se učitelji kemije srečujejo pri poučevanju otrok priseljencev. Mednje spadata tudi poznavanje šolske zakonodaje in sodelovanje s starši otrok priseljencev. Z raziskavo želimo učiteljem kemije in tudi ostalim strokovnim delavcem v vzgoji in izobraževanju predstaviti osnovne smernice za poučevanje kemije v inkluzivnem medkulturnem razredu. Predstavljeni praktični primeri iz kemije z uporabo IKT prikazujejo možnosti za premostitev jezikovnih težav pri pouku kemije. Like many other countries in the European Union, Slovenia also faces the challenge of immigration. Migrants, when joining the new cultural environment, experience problems that are mostly associated with misunderstanding of the new language and ignorance of cultural and social practices. The concept of inclusive education includes the principle of interculturality and requires the systematic work of all involved in the school environment. Teachers face challenges related to understanding the language and different cultures on a daily basis, and they need to know the processes of integration of immigrants and adaptation to the new cultural environment. Teachers are responsible for class preparation, classroom management, and students development. In the master's thesis we present the most common experiences that Chemistry teachers face in the teaching of migrant children. They include knowledge of school legislation and cooperation with parents and other professionals in the education and training the bacis guidelines for teaching Chemistry in an inclusive intercultural classroom. Presented practical problems in Chemistry using ICT show possibilities for overcoming language problems in Chemistry lessons.

Namen magistrskega dela je preveriti, kako na uspešnost preizkusa znanja vplivajo različne ravni učnih kompetenc učencev za učenje kemije. Osnovni namen je preveriti, ali je vpeljava eksperimenta elektroforeze DNK primerna za uporabo v osnovni šoli, kakšen uspeh dosegajo učenci na preizkusu znanja in poznem preizkusu znanja o elektroforezi ter kako tovrsten način poučevanja spodbuja interes učencev za dodatno in bolj poglobljeno učenje kemije. Narejena je bila poglobljena analiza, katere cilje je bilo ugotoviti, ali obstajajo razlike med učenci z različnimi ravnmi avtonomne in kontrolirane motivacije v učnem uspehu in trajnosti znanja o elektroforezi. Namen magistrskega dela je tudi preveriti, kako na uspešnost preizkusa znanja vplivajo različne ravni učnih kompetenc učencev za učenje kemije. Za namen te raziskave je bil razvit in optimiziran eksperiment, ki prikazuje princip elektroforeze DNK in določevanja profila DNK, ki ga učenci lahko izvajajo samostojno. Eksperiment, primeren za laboratorijsko delo v osnovni šoli, je elektroforeza z barvili iz flomastrov ali barvili za živila. Izdelana je bila aparatura za elektroforezo, ki učencem omogoča nazoren vpogled v način izvajanja postopka elektroforeze. Priskrbljeni so bili pripomočki (avtomatska pipeta), ki se jih uporablja pri postopku elektroforeze DNK, da so učenci lahko preverili svoje ročne sposobnosti z instrumenti, ki jih še ne poznajo. Empirični del raziskave vključuje 129 učencev 8. in 9. razredov osnovnih šol iz Ljubljane in okolice, ki obiskujejo izbirna predmeta Poskusi v kemiji in Kemija v življenju. Učenci so pred eksperimentom izpolnili vprašalnik »O razlogih učencev za učenje kemije« in rešili predpreizkus znanja. Po eksperimentu so izpolnili še vprašalnik »Izvedba učne ure« in rešili preizkus znanja o elektroforezi. Dva meseca po eksperimentu so učenci ponovno rešili enak preizkus znanja o elektroforezi. Zbrani podatki so bili kvantitativno analizirani s statističnim programom SPSS. Raziskava kaže, da so bili učenci kljub zahtevnosti in abstraktnosti eksperimenta zelo uspešni tako na prvem kot drugem preizkusu znanja o elektroforezi. V povprečju so učenci dosegli več kot 50 % vseh točk. Podani so rezultati analize dosežkov učencev na preizkusu znanja o elektroforezi glede na različne ravni situacijskega interesa učencev za učenje teh vsebin, avtonomne in kontrolirane motivacije ter učnih kompetenc učencev za učenje kemije. The main purpose of this MA thesis is to find out whether the nucleic acid electrophoresis experiment should be implemented in primary schools, how successfully students pass the preliminary and final test on electrophoresis and how this teaching technique stimulates the students' interest in additional in-depth studying of chemistry. We conducted a thorough analysis with the aim of discovering potential differences in marks and long-term knowledge on electrophoresis between students with different levels of autonomous and controlled motivation. The aim of this MA thesis is also to ascertain how the students' different levels of chemistry study skills influence their test marks. For the purpose of this research we developed and optimised an experiment on the principle of DNA electrophoresis and DNA profiling which the students can perform independently. The experiment is suitable for laboratory work in primary schools and consists of electrophoresis with marker pigments or food pigments. We also constructed a device for electrophoresis that illustrates the method of conducting the electrophoresis procedure. We provided the necessary instruments (automatic pipette) for carrying out the DNA electrophoresis procedure so that the students could test their manual capabilities with unknown instruments. The empirical part of this research included 129 students of the 8th and 9th grade who attended optional subjects “Experiments in chemistry” and “Chemistry in everyday life” at primary schools in Ljubljana and its vicinity. Before conducting the experiment, the students filled out a questionnaire entitled “Reasons why students study chemistry” and passed a preliminary test. After finishing the experiment, they filled out another questionnaire entitled “Study session performance evaluation” and took a test on electrophoresis. Two months after the experiment, the students passed the same test again and the gathered data was quantitatively analysed with the SPSS statistical program. The research shows that students successfully passed both preliminary and final tests on electrophoresis despite the difficulty and abstract nature of the conducted experiment. On average, they achieved 50% of all points on both tests. We were able to obtain interesting results by means of analysis of test performance on electrophoresis based on different levels of students’ situational interest, autonomous and controlled motivation and chemistry study skills.

Kationski polimeri se zaradi svojega pozitivnega naboja vežejo na negativno nabito površino površinskih celic urotelija, pri tem pa povzročijo prekinitve tesnih stikov in posledično luščenje teh celic. Zaradi teh lastnosti se v zadnjem času povečuje njihova uporaba kot potencialnih pomožnih terapevtskih sredstev za odstranjevanje z bakterijami okuženih ali rakavih urotelijskih celic sečnega mehurja. Tak polimer je tudi kationski polisaharid hitosan, ki se je že izkazal za uspešno luščilno sredstvo in zato tudi kot pomožno terapevtsko sredstvo pri zdravljenju bakterijskega cistitisa miši. Z vrstično elektronsko mikroskopijo smo želeli ugotoviti, ali poli-L-lizin, ki je kationski polipeptid, lušči urotelij sečnega mehurja miši. Pri tem nas je zanimalo, ali je delovanje PLL odvisno od njegove koncentracije in molekulske mase ter pri kateri koncentraciji in molekulski masi je njegovo delovanje optimalno. Z našimi poskusi smo potrdili, da poli-L-lizin v pogojih in vivo povzroča prekinitve tesnih stikov in lušči urotelij sečnega mehurja miši. Ugotovili smo tudi, da na obseg luščenja vplivata tako koncentracija kot tudi molekulska masa poli-L-lizina. Luščenje je bilo obsežnejše pri tretiranju urotelija s poli-L-lizinom z višjo molekulsko maso (70-150 kDa) in z višjo koncentracijo (0,01%) kot pa pri tretiranju z nižjo molekulsko maso (30-70 kDa) in nižjo koncentracijo (0,001%). Na osnovi vseh dobljenih rezultatov lahko zaključimo, da je optimalno luščilno sredstvo 0,01% poli-L-lizin z molekulsko maso 70-150 kDa, saj je povzročil obsežno luščenje samo površinskih celic brez luščenja v globino urotelija. Due to their positive charge cationic polymers attach to negatively charged surface of the superficial urothelial cells causing the disruption of tight junctions and consequent desquamation of these cells. Because of these properties their use as potential auxiliary therapeutic agents for elimination of infected urothelial cells or cancer urothelial cells has recently been increasing. Polysaccharide chitosan as one of cationic polymers has already been proved as a successful desquamating substance and also as an auxiliary therapeutic substance for treatment of bacterial cystitis in mice. We used scanning electron microscopy to find out whether poly-L-lysine, which is a cationic polypeptide, causes desquamation of mouse urinary bladder urothelium. The aim of our study was to find out if the effect of poly-L-lysine depended on its concentration and molecular weight and also to determine, at which concentration and molecular weight the effect of poly-L-lysine was optimal. Our experiments confirmed that poly-L-lysine caused the disruption of tight junctions and desquamation of mouse urinary bladder urothelium in in vivo conditions. We found out that both concentration and molecular weight of poly-L-lysine had influence on the extent of cell desquamation. Treatment with higher molecular weight (70-150 kDa) and higher concentration (0,01%) of poly-L-lysine causes more extensive desquamation of urothelial cells than treatment with lower molecular weight (30-70 kDa) and lower concentration (0,001%) of poly-L-lysine. Based on all our results we can conclude that the optimal desquamating substance is the 0,01% poly-L-lysine with molecular weigh of 70-150 kDa because it causes extensive desquamation of solely superficial cells without damaging the other cell layers of the urothelium.

Selen je kemijski element v sledovih in esencialen mikroelement za ljudi, živali in mikroorganizme, medtem ko za rastline to še ni dokazano. Je široko razširjen v zemeljski skorji, pojavlja pa se tudi v tleh, morski ter sladki vodi, rudninah in sedimentih. Na prisotnost selena v okolju vplivajo klimatske razmere, geološka sestava tal in številni antropogeni dejavniki. Pojavlja se v štirih oksidacijskih stanjih. Selenit je najpomembnejša oblika selena v tleh. Ta se lahko zaradi mikrobiološke aktivnosti pretvori v selenat. Selenit in selenat sta najbolj topni anorganski obliki selena in sta zaradi tega za rastline najbolj dostopni. Učinek selena je odvisen predvsem od tega, v kateri obliki in v kakšni koncentraciji je selen prisoten v rastlini. Preučevali smo vpliv različnih koncentracij in oblik selena na biokemijske in morfološke lastnosti male vodne leče. Rastline smo izpostavljali različnim koncentracijam (1 mg/L, 2 mg/L in 5 mg/L) raztopin natrijevega selenita (Na2SeO3) ter različnim koncentracijam (1 mg/L, 2 mg/L in 5 mg/L) raztopin natrijevega selenata (Na2SeO4). Rastline smo izpostavljali tudi kombinaciji selenita in selenata, s koncentracijo 2 mg/L selenata in 2 mg/L selenita. Uporabili smo tudi kontrolno skupino, ki je rasla v rastnem gojišču brez dodanega Se. Med poskusom smo merili fotokemično učinkovitost fotosistema II (FS II) s fluorometrom PAM 2500, aktivnost elektronskega transportnega sistema (ETS), s prostim očesom pa smo opazovali morfološke spremembe (sprememba barve stebelnih členkov, štetje stebelnih členkov in propadanje korenin) ter pripravili vzorce za merjenje fotosinteznih barvil (klorofil a, klorofil b, karotenoidi) in antocianov. Na koncu poskusa smo stehtali svežo in suho maso vseh rastlin in opravili meritve fotosinteznih barvil. Ugotovili smo, da so rastline, ki so bile izpostavljene koncentracijam (1 mg/L, 2 mg/L in 5 mg/L) natrijevega selenata, (1 mg/L, 2 mg/L in 5 mg/L) natrijevega selenita ter kombinaciji natrijevega selenita in natrijevega selenata, slabše rasle ter so imele posledično nižjo fotokemično učinkovitost fotosistema II (FS II), nižjo aktivnost elektronskega transportnega sistema (ETS) in nižje koncentracije fotosinteznih barvil. Študija bo pripomogla k razumevanju vpliva različnih oblik in koncentracij selena na malo vodno lečo. Selenium is a trace element and an essential microelement for humans, animals and microorganisms, whereas this has not been established for plants yet. It is widespread in the earth's crust and occurs in soil, seawater and freshwater as well as minerals and sediments. Climatic conditions, geological composition of the soil and numerous anthropogenic factors affect the presence of selenium in the environment. It can exist in four oxidation states. Selenite is the most important form of selenium in soil. It can convert into selenate due to microbiological activity. Being the most soluble inorganic forms of selenium, selenite and selenate are the most accessible to plants. The effect of selenium depends mainly on its form and concentration in plants. We studied the influence of different concentrations and forms of selenium on biochemical and morphological characteristics of common duckweed. Plants were exposed to various concentrations (1 mg/L, 2 mg/L and 5 mg/L) of sodium selenite solutions (Na2SeO3), various concentrations (1 mg/L, 2 mg/L and 5 mg/L) of sodium selenate solutions (Na2SeO4) and to a combination of selenite and selenate with a 2 mg/L concentration. Furthermore, we used a control group cultured in growth medium with no Se added. During the experiment, we measured the photochemical effect of photosystem II (FS II) with the PAM 2500 fluorometer, the activity of the electron transport system (ETS) and observed with the naked eye the morphological changes (changes in frond colour, counting fronds and root degradation) as well as prepared the samples for the measurement of photosynthetic pigments (chlorophyll a and b, carotenoids) and anthocyanins. We have established that plants that have been exposed to concentrations (1 mg/L, 2 mg/L and 5 mg/L) of sodium selenate, (1 mg/L, 2 mg/L and 5 mg/L) of sodium selenite and the combination of selenite and selenate, grew and developed poorly under stress conditions. Consequently, their photochemical effect of photosystem II (FS II), activity of the electron transport system (ETS) and concentrations of photosynthetic pigments were lower. This study will improve the understanding of how different forms and concentrations of selenium affect the common duckweed.

Medpredmetno povezovanje je danes prav gotovo ena od oblik sodobnega poučevanja. Nekateri cilji sodobne šole že sami po sebi zahtevajo usklajeno načrtovanje učiteljev različnih predmetov in področij. Velikokrat ostane to povezovanje samo na ravni učnih vsebin, ne pa tudi v načinu poučevanja. V izvedenem primeru je bil vodilni predmet tehnika in tehnologija. Ta se je povezoval s kemijo, fiziko ter izbirnim predmetom obdelava kovin. Poučevanje je potekalo timsko, kjer sva se učiteljici medsebojno dopolnjevali v znanju, sposobnostih in spretnostih. Želeli sva, da učenci s skupnimi dejavnostmi in procesi povežejo znanja o kovinah in nekovinah različnih predmetnih področij, določeno vsebino usvojijo čim bolj celostno ter pridobijo trajnejše in kakovostnejše znanje. Učenci so z eksperimentalnim delom, reševanjem problemov, iskanjem informacij in sodelovalnim učenjem spoznali lastnosti kovin, ki so jih v naslednjih urah uporabili pri izdelavi izdelka iz kovin. Pokazali so veliko zanimanje za tovrstno obliko pouka, bili so bolj motivirani, iznajdljivi, ustvarjalni in bolj samostojni kot običajno. Znanja so povezali v celoto – to je bil tudi namen medpredmetnega povezovanja. Pridobljeno znanje je tako širše in praktično uporabno. Izvedeni primer lahko ponavljamo in nadgrajujemo, prenosljiv je tudi na nove primere in druge predmete. Cross-curricular integration is certainly one of the forms of modern teaching nowadays. Some of the aims of modern schooling already demand a coordinated planning of interaction between teachers of different subjects and areas. Integration is often dealt with only on the level of teaching topics, not teaching methods. For the research we integrated the subject Crafts and Technology with Chemistry, Physics and the optional subject – Handling of Metal. The teaching was carried out in teamwork, where my colleague and me complemented each other’s knowledge, professional expertise and skills. We wanted our students to integrate their knowledge about metals and nonmetals in joined activities in different school subjects, to learn the contents in its wholeness and gain a more permanent knowledge of greater quality. The students first got to know the qualities of metals through experimental work, information seeking, problem solving and cooperative learning, which then they then used in lessons on how to manufacture a metal product. They showed great interest for this kind of lesson form and were more motivated, resourceful, creative and independent than usual. They combined their knowledge into a whole, which is the purpose of cross-curriculum integration. They also gained knowledge in a broader and more practical way. The test lesson we prepared can be repeated and enhanced or transferred and adapted to new situations and other subjects.

V teoretičnem delu diplomske naloge je bila zbrana in pregledana literatura s področja diferenciacije in individualizacije pri pouku. Pri tem sta opredeljena pojma diferenciacija in individualizacija ter razdelana vloga obeh pojmov v učnem načrtu za kemijo v osnovni šoli. V nadaljevanju so predstavljene temeljne smernice, navodila in koncepti v zvezi z diferenciacijo in individualizacijo v slovenskem šolskem prostoru, ki so bile sprejete na Strokovnem svetu Republike Slovenije za splošno izobraževanje. V teoretičnem delu naloge sta nato opredeljena vloga in pomen eksperimentalnega dela pri pouku kemije, izhajajoč iz učnega načrta za kemijo v osnovni šoli. Opisane so tudi oblike eksperimentalnega dela. V praktičnem delu diplomske naloge je predstavljena možnost za učno diferenciacijo eksperimentalnega dela učencev na primeru izbrane eksperimentalne vaje, primerne za osnovnošolsko raven poučevanja kemije. Za prikaz učne diferenciacije je bila izbrana eksperimentalna vaja prilagojena na treh ravneh, v nalogi poimenovane diferencirane izvedbe eksperimentalne vaje za učence z učnimi težavami, povprečne učence in za nadarjene učence. Prilagoditve navedenih ravni se nanašajo na predvideno število izvedenih poskusov, zahtevnost nalog delovnega lista ter vodenje učencev pri izvedbi eksperimentalnega dela. V podporo vsem trem diferenciranim izvedbam eksperimentalne vaje so bila razvita učiteljeva navodila in delovni listi za učence. The first part of the graduation thesis comprises collected and reviewed literature about differentiation and individualisation in the classroom. The terms differentiation and individualisation are explained and their role in the Chemistry Curriculum for primary schools is elaborated. Furthermore, basic guidelines, instructions and concepts, concerning differentiation and individualisation in Slovene schools, which were confirmed by the Council of Experts of the Republic of Slovenia for General Education, are presented. In the theoretical part of the graduation thesis, the role and the meaning of experimental work in Chemistry classrooms are elaborated, based on the Chemistry Curriculum for primary schools. Also, the various forms of experimental work are described and guidelines for the development of teaching materials for the experimental work monitoring are given. The second part of the graduation thesis presents possibilities for differentiation of the students’ experimental work, elaborated on one example of chemistry lecture for primary level chemistry (grades 8 and 9). For this purpose, an example of chemistry lecture based on students` experimental work is developed in three-fold level: (1) students` with learning difficulties, (2) average students and (3) gifted students. Differentiation of students` chemical experimental work is based on: different number of anticipated experiments, different complexity of the tasks on the worksheet and various extend of guiding pupils when carrying out the experimental work. In support to all three differentiated versions of students` experimental work the following teaching materials have been developed: teacher’s instructions for simultaneous implementation of differentiated students` experimental work, three versions of worksheets for students based on three differentiated implementations of experimental work.