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Abstract: Liquefied wood-based polyurethane wood coatings of an aesthetically acceptable light colour were prepared and characterised. Liquefied black poplar wood was obtained by solvolysis in a polyethylene glycol/glycerol mixture, and it was bleached with hydrogen peroxide. The bleaching treatment converted liquefied wood from a dark brown to a yellowish product. Polyurethane films were prepared by the curing of liquefied wood with polymeric diphenylmethane diisocyanate or trimethylolpropane toluene diisocyanate prepolymer (TMP/TDI) isocyanate-type hardeners. It was found that the selected properties of the films prepared from the bleached liquefied wood were, in general, equivalent to those prepared from unbleached liquefied wood. The mechanical properties of the films obtained with the TMP/TDI curing agent were acceptable for wood coating applications. The initial poor resistance of the films to water and ethanol was substantially improved by the addition of n-octyltriethoxysilane to the liquefied wood prior to the preparation of the polyurethane coatings; the hardness of the films also increased.
Keywords: utekočinjen les, poliuretanski premaz, les, beljenje
Published in RUP: 03.04.2017; Views: 3436; Downloads: 131
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Keywords: predšolski otroci, igre, načrtne dejavnosti, matematika, štetje, strategije štetja
Published in RUP: 10.11.2016; Views: 2967; Downloads: 97
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Abstract: Background. Several methods that are currently used for contouring analysis have problems providing reliable and/ or meaningful results. In this paper a solution to these problems is proposed in a form of a novel measure, which was developed based on requirements defined for contouring studies. Materials and methods. The proposed distance deviation measure can be understood as an extension of the closest point measures in such a way that it does not measure only distances between points on contours but rather analyse deviation of distances to both/all contours from each image point/voxel. The obtained result is information rich, reliable and provided in a form of an image, enabling detailed topographic analysis. In addition to image representation, results can be further processed into angular representation for compact topographic analysis or into overall scalar estimates for quick assessment of contour disagreement. Results. Distance deviation method is demonstrated on a multi observer contouring example with complex contour shapes, i.e., with pronounced extremes and void interior. The results are presented using the three proposed methods. Conclusions. The proposed method can detect and measure contour variation irrespective of contour complexity and number of contour segments, while the obtained results are easy to interpret. It can be used in various situations, regarding the presence of reference contour or multiple test contours.
Keywords: contouring, contour comparison, distance transform
Published in RUP: 21.12.2015; Views: 2782; Downloads: 123
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Keywords: kras, kraški vodonosniki, podzemno pretakanje, sledenje voda, sledila, hidrologija, geografija, Slovenija, diplomska dela
Published in RUP: 10.07.2015; Views: 3884; Downloads: 52
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Keywords: predšolski otroci, matematika v vrtcu, drugo starostno obdobje, razvrščanje, drevesni prikaz, Carrollov prikaz
Published in RUP: 10.07.2015; Views: 5382; Downloads: 402
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