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Povzetek: In St. Jacob’s parish church in Ormož, Slovenia, mural paintings from around 1350–1370 are partially conserved in the northeastern corner of the main nave. They are almost completely black, indicating a large-scale pigment degradation. They were studied as a part of a larger research project aiming to identify materials applied and their possible degradation. First, they were studied in situ, and next, extracted samples of plaster, pigments, and colour layers were analysed by optical microscopy, Raman spectroscopy, FTIR spectroscopy, SEM-EDS, and XRD. Haematite, green earth, malachite, azurite, and tenorite were identified, showing that azurite and perhaps also malachite degraded to black tenorite, probably due to their fine grinding and their application directly on the fresh plaster. The plaster is made with small and large amounts of aggregate with mostly quartz with some impurities, which makes it fragile. The original appearance of these murals was of bright blue and green colours.
Ključne besede: mural painting, medieval painting, Gothic art, St. Jacob's Church, Ormož, Slovenia, pigments, chemical structure, colour degradation, optical microscopy, Raman microspectroscopy, FTIR, XRD
Objavljeno v DiRROS: 17.04.2024; Ogledov: 39; Prenosov: 14
Celotno besedilo (81,04 MB)
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Povzetek: The scheme of engineering-construction assessment created based on engineering-geological zoning of the city’s territory is desirable among additional graphic materials in the design of master plans projects as determined by building regulations. Engineering-geological zoning provides for different ranks’ selection of engineering-geological units (EG units), which have a particular range of common engineering-geological conditions that ultimately determine the construction sites’ affiliation to a specific suitability category. Geological-genetic structure of Irpin city of Kyiv region (Ukraine) is explored in this article. A variant of the creation of a large-scale engineering-geological map and corresponding geological-lithological sections by supporting boreholes in the borders of the city based on the engineering-geological survey conducted is presented. The obtained result allowed the selection of engineering geological zoning units – engineering geological districts by general conditions of geological development and subdistricts by engineering-geological complexes of Quaternary rocks’ thickness. The analysis of soils’ geomechanical properties (engineering-geological elements) lays the foundations for the selection of engineering-geological sites based on the comparison of this information with geomorphological, hydrogeological and geodynamic data. Accounting of geological-lithological factors in the preparation of the construction assessment scheme in the project of Irpin city’s master plan has become the ultimate result.
Ključne besede: engineering-geological zoning, engineering-geological units, geological-genetic structure, engineering-geological map, construction assessment
Objavljeno v DiRROS: 15.01.2024; Ogledov: 159; Prenosov: 119
Celotno besedilo (24,13 MB)

Povzetek: New mutations provide the raw material for evolution and adaptation. The distribution of fitness effects (DFE) describes the spectrum of effects of new mutations that can occur along a genome, and is, therefore, of vital interest in evolutionary biology. Recent work has uncovered striking similarities in the DFE between closely related species, prompting us to ask whether there is variation in the DFE among populations of the same species, or among species with different degrees of divergence, that is whether there is variation in the DFE at different levels of evolution. Using exome capture data from six tree species sampled across Europe we characterized the DFE for multiple species, and for each species, multiple populations, and investigated the factors potentially influencing the DFE, such as demography, population divergence, and genetic background. We find statistical support for the presence of variation in the DFE at the species level, even among relatively closely related species. However, we find very little difference at the population level, suggesting that differences in the DFE are primarily driven by deep features of species biology, and those evolutionarily recent events, such as demographic changes and local adaptation, have little impact.
Ključne besede: DFE, deleterious mutations, population structure, forest trees
Objavljeno v DiRROS: 12.12.2023; Ogledov: 221; Prenosov: 94
Celotno besedilo (1,15 MB)
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Povzetek: This study introduces a novel geotechnical composite material comprising two types of fill material sourced from the paper industry-deinking paper sludge ash (DPSA) and deinking paper sludge (DPS). Five composites with different DPSA and DPS contents were investigated. Two composites were selected for further analyses. The technology and procedure for composite installation were implemented in field tests. The composites with 80% and 70% DPSA exhibited the elasticity required to withstand minor landslide slip deformations, in addition to achieving sufficiently high values of uniaxial compressive strength. The composites had a low maximum dry density value, which led to fewer settlements in the entire support structure. The enhanced shear characteristics can enable the construction of a thinner retaining wall. The delay between preparation and installation of the composites was further investigated. The field tests confirmed that the composites with 80% and 70% DPSA can be installed on the construction site 4 h and even 24 h after mixing. In 2018, a retaining wall structure with 70% DPSA and 30% DPS was successfully implemented near a railway line using conventional technology as followed-up research to the herein presented study. Results have been derived from work performed in the scope of the H2020 Paperchain project in which novel circular economy models centered on the valorization of the waste streams generated by the pulp and paper industry as secondary raw material for several resource-intensive sectors, including the construction sector, have been developed. Environmental benefits are savings in natural raw materials, reduction of landfill disposal as well as CO2 emission reduction.
Ključne besede: deinking paper sludge ash, deinking paper sludge, secondary resources, fill material, geotechnical structure, landslide, open access
Objavljeno v DiRROS: 04.07.2023; Ogledov: 253; Prenosov: 200
Celotno besedilo (1,63 MB)
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Povzetek: Hydraulic actions on bridges are a leading cause of failure, especially due to the occurrence of scour erosion. Due to climate change, flooding and scour risks are exacerbating for bridges worldwide, leading to a significant stress burden on asset management agencies. Assessing structures for scour has received significant attention in recent years, however, there are few studies which investigate the influence of scour on the components of a bridge to understand how various elements interact. Moreover, the presence of debris loading, which can occur due to flooding causing debris to become lodged at structures, has not received significant attention. Debris can worsen scour conditions and increase hydraulic loading on a bridge. In this paper, an analysis of the response of various components of a roadway bridge when exposed to extreme flooding is conducted. The influence of scour and debris on hydraulic loading, internal forces, modal periods, and utilization ratios of various bridge components is ascertained. A numerical model is developed using OpenSees employing two different methods to model the soil-structure interaction. Results for several flooding scenarios show how the various bridge elements are influenced by variations in water height and velocity, scour depth, and presence of debris.
Ključne besede: local scour, wood debris, flooding, resilience, soil-structure interaction, bridges, open access
Objavljeno v DiRROS: 29.05.2023; Ogledov: 293; Prenosov: 232
Celotno besedilo (4,32 MB)
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