21. |
22. |
23. Development of multi-component fluoropolymer based coating on simulated outdoor patina on quaternary bronzeTadeja Kosec, Luka Škrlep, Erika Švara Fabjan, Andrijana Sever Škapin, Giulia Masi, Elena Bernardi, Cristina Chiavari, Claudie Josse, Jerome Esvan, Luc Robbiola, 2019, original scientific article Abstract: Bronze reacts with oxygen, humidity, and pollutants in the atmosphere so that a patina forms. Natural exposure to an outdoor atmosphere can be simulated and accelerated in order to achieve a patina that mimics outdoor ancient patina. In order to avoid the uncontrolled dissolving of either the natural or artificially formed patina, protection of the patina is needed.
In this study, a multi-component fluoropolymer based coating for the protection of bronze patina was developed. In order to provide various functionalities of the coating (such as the hydrophobicity of the coating surface, obtaining interactions within the coating itself as well as a bronze substrate and inhibiting the corrosion processes), a fluoroacrylate coating with appropriate adhesion promoter was suggested, with and without a silane modified benzotriazole inhibitor. The protective efficiency and durability of the applied coatings were investigated electrochemically using potentiodynamic tests and electrochemical impedance spectroscopy in a simulated acid rain solution. All of the developed coatings showed a significant decrease in the corrosion current density. The self-assembled single layer coating (FA-MS) also showed 100% inhibition efficiency. After ageing the coating remained transparent and did not change by UV exposure and/or thermal cycling. The patina and coating investigations using FIB-SEM and EDX showed that the latter coating (FA-MS) successfully covered the surface of the patinated bronze. The mechanism of the bonding was proposed and supported with the spectroscopic observation of a thin and even coating.
Keywords: bronze, patina, fluoropolymer coating, atmospheric corrosion
Published in DiRROS: 25.10.2023; Views: 389; Downloads: 214
 Full text (2,17 MB)
This document has many files! More... |
24. |
25. |
26. |
27. Doktrinarni problemi diagnostičnega algoritma retroperitonealnega prostoraJurij Us, Franci-Stanko Marolt, Marjeta Stanovnik, Jože Stropnik, Erika Brenčič, Marjeta Demšar, V. Istenič, E. Baretič-Kolar, Marko Kralj, 1982, professional article Keywords: radiologija, intervencijska radiologija
Published in DiRROS: 14.09.2023; Views: 273; Downloads: 64
Full text (302,79 KB) |
28. |
29. |
30. Colorimetric cutoff indication of relative humidity based on selectively functionalized mesoporous silicaErika Švara Fabjan, Peter Nadrah, Anja Ajdovec, Matija Tomšič, Goran Dražić, Matjaž Mazaj, Nataša Zabukovec Logar, Andrijana Sever Škapin, 2020, original scientific article Abstract: We present a novel % cutoff concept of colorimetric indication of relative humidity based on dye dissolution in condensed water in capillaries of selectively functionalized mesoporours host SiO2 material. Consistently high levels of indoor air humidity induces mold and algae growth which represent a potential risks for human health and have deteriorating effect on walls as well. Simple localized humidity detection of high humidity with naked eye especially at places with low air circulation, where growth of mold usually starts first, is therefore highly desirable. The reporting dye was integrated in the non-functionalized mesoporous silica matrix with different pore diameters and selective-functionalized mesoporous silica material. After exposure to the environment of different air humidities the dye dissolved in water causing color change of adsorbent. With the use of adsorbents with different mesopore diameters high ability to tune the value of relative humidity when complete capillary condensation occurred was achieved. Materials with pore diameters of 3.0%nm, 3.5%nm and 7.0%nm exhibit gradual color change when reaching relative humidity up to 55, 79 and 88 RH% respectively. After selective methylation of the material with 7.0%nm pore diameter, non-gradual cutoff color change was achieved. Sample exhibited color change at narrow range of relative humidity (cutoff color change). Due to selective functionalized outer surface the dye dissolution occur only in condensed water in pores and therefore provide colorimetric indication only in this range. Selectively modified silica material has a great potential for a straightforward detection of high humid environment.
Keywords: turn-on colorimetric probe, selective functionalization, mesoporous silica, relative humidity, capillary condensation
Published in DiRROS: 05.09.2023; Views: 326; Downloads: 240
Full text (7,18 MB)
This document has many files! More... |
