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V magistrskem delu so predstavljene meritve močenja in kapilarnega dviga vode, glicerola, silikonskega olja in tekočega kristala na obdelanih steklenih površinah z namenom določitve površinske napetosti. Delo je sestavljeno iz teoretičnega opisa kapilarnih pojavov s poudarkom na računanju oblike meniskusa in višine kapilarnega dviga, predstavitve fizikalnih lastnosti uporabljenih materialov in eksperimentalnih metod ter rezultatov. Razvil sem postopek merjenja kontaktnih kotov kapljevin na ravnih podlagah s prilagojenim optičnim mikroskopom s horizontalno postavitvijo objektivov, ki je bil uporaben tudi za določanje oblike meniskusov in meritve višin kapilarnih dvigov v cilindričnih kapilarah. Ugotovil sem, da ima obdelava steklenih površin s silanom različen vpliv na močenje polarnih in nepolarnih kapljevin, kar se pozna tudi pri spreminjanju višine kapilarnih dvigov. Pokazal sem tudi, da se anizotropne lastnosti nematskega tekočega kristala izrazijo v anizotropiji površinske napetosti, ki je odvisna od robnih pogojev na površini stekla. Metoda kapilarnega dviga v ozkih cilindričnih kapilarah se je izkazala kot enostaven, učinkovit, ponovljiv in dovolj natančen način določanja površinske napetosti različnih vrst kapljevin, ki je uporabna tudi za raziskovanje vpliva kemijske funkcionalizacije površin na lastnosti močenja. The master’s thesis presents measurements of wetting and capillary rise of water, glycerol, silicone oil and nematic liquid crystal on chemically treated glass surfaces with intention of determining the surface tension. The work consists of a theoretical description of the capillary phenomena, presentation of the physical properties of the materials, applied experimental methods and final results. I demonstrated the technique of measuring the contact angles of liquids on flat surfaces with an adjusted optical microscope which was also applied to measure the shape of liquid meniscus and the height of capillary rise in cylindrical capillaries. I have shown that the functionalization of glass surfaces with a silane strongly influences wetting of polar and non-polar liquids, which is also reflected in changing the height of the capillary rise. Further, I demonstrated that the anisotropic properties of a nematic liquid crystal are reflected in anisotropy of the surface tension since it strongly depends on the glass surface boundary conditions. I found that the method of capillary rise provides simple, accurate, comparable and reproducible way of determining the surface tension of various types of liquids. Lastly, it can be also used to investigate wetting properties on chemically functionalized surfaces.

Ohranjanje kulturne dediščine se v zadnjih letih še posebej odraža z množičnim saniranjem propadajočih objektov, ki na različne načine kazijo okolico, v kateri se nahajajo. V diplomskem delu je predstavljena rekonstrukcija Mencingerjeve hiše, ki leži v starem mestnem jedru Krškega in ima velik zgodovinski pomen. Analizirano je bilo obstoječe stanje pred pričetkom del in opisani cilji rekonstrukcije ter predvideni sanacijski ukrepi, ki so bili omejeni s pogoji ZVKDS. Opisan je bil potek rekonstrukcije in posamezne tehnologije sanacij. Preverili in analizirali smo obstoječe stanje junija letos. Na podlagi vizualnega pregleda in pogovorov smo ocenili uspešnost rekonstrukcije in podali mnenje oz. rešitve, ki bi se lahko izvedle v prihodnosti. Preservation of cultural heritage in recent years reflects particularly in the massive renovations of degraded buildings, which in many aspects downgrade the neighborhood. The present thesis deals with the reconstruction of Mencinger’s house, located in the old town of Krško and holds a great historical significance. Circumstances prior to the start of reconstruction were analyzed in the thesis, the aims of the process were described, as well as estimated remedial measures, limited by The Institute for the Protection of Cultural Heritage of Slovenia’s conditions. Furthermore, the thesis includes the development of reconstruction and specific renovation technologies. In June 2016, we examined and analyzed the existing situation. Based on visual inspection and the discussions, we evaluated the success of reconstruction, expressed our opinion and delivered possible improvements for the future.

Predmet obravnave diplomskega dela je starejša spomeniško zaščitena kmečka hiša, na kateri so posegi omejeni s strani Zavoda za varstvo kulturne dediščine Slovenije. Za odpravo vdora vlage, ki je glavni problem hiše, smo na podlagi predhodnih preiskav raziskali vzroke in zanje podali več možnosti pravilnega pristopa k ustrezni sanaciji. Zaradi stanja objekta in investitorjeve želje po dodatnih bivalnih in pomožnih prostorih, je predvidena rekonstrukcija celotnega neizkoriščenega strešnega krova v mansardni prostor. Podana je tudi najugodnejša rešitev posega v objekt za katero je izdelan projektantski predračun gradbenih in obrtniških del, vključno z popisom del, izračunom količin in oceno vrednosti posameznih predračunskih postavk. The subject of the graduate work is an older monument house on which the procedures are limited from the side of the Institute for the Protection of Culture Heritage of Slovenia. For the elimination of moisture invasion, which is the main problem of the house, we have researched the cause of the problem and, based on the previous research, offered various options for the correct approach in sanitizing the house. Due to the condition of the building and the investor`s wish for additional living space and subsidiary area, a reconstruction of the whole unexploited roof area, resulting in an attic apartment is predicted. The most advantageous option for the building procedure is also offered, for which the unit price estimate for building and trade works is made, including work inventory, quantity take-off calculations and unit price estimating of individual activities.

Namen magistrske naloge je bil postavitev merilne naprave in razvoj nove metode merjenja površinske napetosti s kapilarnim dvigom dvofaznih sistemov v okolici kritične točke. Za pridobitev natančnih in primerljivih meritev je bilo potrebno poznati natančni notranji premer tankih kapilar. Določili smo ga z metodo laserskega tipanja na nemški koordinatni merilni napravi ZEISS tipa UMC-850 s pomočjo merilne programske opreme CALYPSO 5.1.4. Za merjenje ravnotežne višine smo uporabili računalniški program Logger Pro, ki omogoča natančno analizo razdalj med dvema točkama. Gostote dvofaznih sistemov smo dobili iz podatkovne baze NIST ali jih izmerili s pomočjo gravimetrične metode jemanja vzorcev iz mešalnega avtoklava. Površinsko napetost smo merili v treh dvofaznih sistemih: voda/CO2, slanica/CO2 in polimer PEG/CO2 v razponu od 1 bara do 200 barov. Prve meritve smo izvedli za sistem voda/CO2 pri treh izotermah (25 °C, 45 °C in 60 °C) in jih primerjali z literaturo. Ugotovili smo, da daje naša metoda primerljive in ponovljive rezultate, ki kažejo, da se s povečanjem tlaka površinska napetost linearno zmanjšuje do območja fazne spremembe CO2, v območju višjih tlakov pa doseže konstantno vrednost. Zanimiva je tudi ugotovitev, da se površinska napetost pri atmosferskih pogojih z nižanjem temperature poveča, v območju višjih tlakov pa pada. Zaradi možnosti skladiščenja toplogrednega plina CO2 v slanico smo v avtoklavu simulirali razmere, ki potekajo pri vbrizgavanju CO2 v slane reke več kilometrov pod zemljo. Ugotovili smo, da se z višanjem koncentracije soli v vodni raztopini (od 14 g/l do 200 g/l) viša vrednost površinske napetosti. Z namenom pridobitve še neraziskanih termodinamskih podatkov v okolici kritične točke smo izmerili površinsko napetost sistema polimera PEG/CO2. Rezultati kažejo, da se je površinska napetost sistema PEG/CO2 (molske mase PEG: 200, 400, 600) s povečanjem tlaka prav tako linearno zmanjševala. The aim of the thesis was to place a measuring device for determination of the surface tension by the capillary rise method in two-phase systems at higher pressures. In order to obtain accurate and comparable measurements, it was necessary to know the exact inner diameter of the thin capillaries, which we have determined by measuring on the German coordinate machine ZEISS type UMC - 850 using a software CALYPSO 5.1.4. To measure the equilibrium height, we used a computer program Logger Pro, which enables detailed analysis of distances between two points. The densities of two-phase systems were obtained from the NIST database, or measured by the gravimetric method of taking samples from the mixing autoclave. Surface tension was measured in the three two-phase systems: water/CO2 brine/CO2 and polymer PEG/CO2 in the range from 1 bar to 200 bar. The first measurements were performed for the system water/CO2 for three isotherms (25° C, 45° C and 60° C) and compared with the literature. We found that our method provides comparable and reproducible results. As pressure increases, a decrease in the interfacial tension is observed, which is more pronounced at lower temperatures. At lower pressures surface tension decreases with rising temperature at higher pressures the opposite effect is found. Due to the potential of storage of the greenhouse gas CO2 in brine, we simulated conditions in an autoclave, which take place when injecting CO2 into saline river several hundred meters underground. We found that by increasing the salt concentration in the aqueous solution (form 14g/l to 200g/l) the surface tension value increases. In order to obtain so far unexplored thermodynamic data, surface tension of the system polymer PEG/CO2 was measured. The results show that by increasing pressure the surface tension of the system PEG/CO2 (molar mass of PEG: 200, 400, 600) decreased linearly likewise.

Diplomsko delo je razdeljeno na dva dela – teoretični in praktični del. V teoretičnem delu podrobneje predstavimo izkustveno učenje, njegove idejne izvore ter navedemo metode in faze takega učenja. V nadaljevanju opredelimo naravoslovje in naredimo vertikalni pregled naravoslovnih predmetov v osnovni šoli, kjer so za vsak predmet izpisani splošni učni cilji. Predstavimo naravoslovne dejavnosti, naravoslovne kompetence ter namenimo nekaj besed začetnemu naravoslovju in konstruktivizmu. Navedene so tudi naravoslovne metode dela, nekaj več pa povemo o metodi eksperimentiranja in jo podrobneje opišemo. Za konec teoretičnega dela predstavimo še oddelek podaljšanega bivanja, njegove sestavine in organizacijo dela v oddelku. V drugem, praktičnem delu diplomske naloge je opisana izvedba eksperimenta kapilarnega dviga vode, ki smo ga izvedli v oddelku podaljšanega bivanja na Osnovni šoli Dolenjske Toplice. Z njim smo želeli preveriti, ali učenci z učenjem preko lastnih izkušenj res pridobijo več znanja kot samo z razlago ter po končani evalvaciji delovnih listov dokazali, da je uporaba izkustvenega učenja pri vsakdanjem pouku za učence še kako pomembna. This graduation thesis consists of two parts, theoretical and empirical. The theoretical part introduces empirical learning, its origin, methods and stages. Natural science is defined and subjects of natural science in a primary school, where general learning aims for each subject are written out, are vertically reviewed. Natural science activities and natural science competences are presented, and primary natural science and constructivism are also mentioned. Also, natural science methods are indicated also, and experimental method is defined and described too. Finally, an after school class, its characteristics and the organisation of work are presented. The second, empirical part describes the capillary water rise experiment, which was carried out in the after school class of the Dolenjske Toplice primary school. The intention was to determine whether pupils gain more knowledge by learning through personal experience or by just listening to an explanation. Evaluation of worksheets proved that the use of empirical learning in everyday classes is very important.