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1533. Diketopyrrolopyrrole pigment core@multi-layer ▫$SiO_2$▫ shell with improved photochemical stabilityErika Švara Fabjan, Zineb Saghi, Paul A. Midgley, Mojca Otoničar, Goran Dražić, Miran Gaberšček, Andrijana Sever Škapin, 2018, izvirni znanstveni članek Povzetek: A model organic pigment (diketopyrrolopyrrole) is encapsulated by a silica coating in order to improve its photochemical stability. Unlike in previous works where single-layer silica coatings were used for similar purposes, we here propose creation of a multi-layer silica shell synthesized via in-situ sol-gel method, which should significantly improve the homogeneity and thus the protection ability of the coating. This is done by repeating the basic two-step process (pigment surface modification and silica encapsulation) several times, creating the final protective shell in a layer-by-layer fashion. The compositional and structural properties of the prepared coatings is studied using Fourier-transform infrared spectroscopy, differential thermal and thermogravimetric analysis, nitrogen adsorption measurements and transmission electron microscopy. Photochemical stability of non-encapsulated and encapsulated pigment particles is evaluated via the so-called fast-irradiation method. Various correlations between the essential coating properties, such as thickness, porosity, SiO2 content, and the corresponding photochemical stability of the samples are established and discussed in detail. As a whole, our results confirm the basic hypothesis, that multiple-layered silica shells show improved pigment protection ability in comparison to the single-layer coatings. Ključne besede: organic pigments, silica coating, encapsulation, morphology, photocemical stability Objavljeno v DiRROS: 27.03.2024; Ogledov: 474; Prenosov: 195
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1534. Lessons learned from the monitoring of retaining structures, built in demanding geotechnical conditions in SloveniaPavel Žvanut, Janko Logar, 2019, objavljeni znanstveni prispevek na konferenci Povzetek: A typical retaining structure built with large-diameter bored piles in soft clastic rock, and sup-ported by pre-stressed permanent ground anchors, is discussed. Step-by-step back analyses were performed. A simplified geological structure was first used in the analyses, together with a simple Mohr-Coulomb model. The results were compared with more complex analyses using a Hardening Soil model and a more detailed geological structure. Much better results were obtained with the use of the HS model, which is more suitable for the modelling of rock of such a type, but even with the use of the MC model the final results were quite good, making the use of the observational method attractive for engineers. Ključne besede: geotechnics, gretaining structures, bored piles, numerical modelling, finite element method, observational method Objavljeno v DiRROS: 27.03.2024; Ogledov: 341; Prenosov: 185
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1535. Modelling of traffic load effects in the assessment of existing road bridgesDominik Skokandić, Ana Mandić Ivanković, Aleš Žnidarič, Mladen Srbić, 2019, pregledni znanstveni članek Povzetek: Traffic load models used for the design of new bridges are based on conservative assumptions and have not been proven efficient for assessing safety of existing bridges. In the case of existing bridges, it is reasonable to use load models that are based on bridge weigh-in-motion data which, in addition to axle loads and spacing of bridge-crossing vehicles, provide information on bridge behaviour under traffic load. This paper provides an overview of traffic load models, as well as guidelines on the use of weigh-in-motion data when assessing condition of existing road bridges. Ključne besede: prometna obtežba, tehtanje vozil med vožnjo, mostni WIM, ocenjevanje stanja, obstoječi mostovi, traffic load, weigh-in-motion, bridge WIM, condition assessment, existing bridges Objavljeno v DiRROS: 27.03.2024; Ogledov: 358; Prenosov: 301
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1536. Validation of the recycled backfill material for the landslide stabilization at a railway lineKarmen Fifer Bizjak, Barbara Likar, 2024, izvirni znanstveni članek Povzetek: In mountain areas landslides many times endanger safety of transport infrastructures, and these must be stabilized with retaining wall structures. In this paper the validation of a new composite as a backfill material for landslide stabilization with a large scale demo retaining wall is presented. The new composite was made from residues of paper industry, which uses for its production deinking process. New composite was validated with the laboratory tests, construction of small demo sites and at the end with a large demo retaining wall structure with a length of 50 m. It was concluded that the paper sludge ash and the paper sludge are in proportion 70:30, compacted on the optimal water content and maximum dry density, reached sufficient uniaxial compressive and shear strength. However, the composite's hydration processes required the definition of an optimal time between the composite mixing and installation. In 2019, the retaining wall structure from the new composite was successfully built. The large demo structure is an example of the knowledge transfer from the laboratory to the construction site, in which composite and installing technology could be verified. Ključne besede: landslides, recycled backfill material, paper sludge ash, geotechnical composite, railway line, recycled material, environment Objavljeno v DiRROS: 26.03.2024; Ogledov: 327; Prenosov: 237
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1537. Truffle mycorrhization in a pecan orchardMylla Trisha Mello Souza, Joice Aline Freiberg, Tine Grebenc, Marcelo Aloisio Sulzbacher, Diniz Fronza, Juliano Borela Magalhães, Vanessa da Rosa Gonçalves, Nathalie Caroline Hirt Kessler, Lucas Moura Somavilla, Zaida Ines Antoniolli, 2024, izvirni znanstveni članek Povzetek: The ectomycorrhizal association of Tuber spp. in orchards is essential for truffle production. In this sense, this study aimed to evaluate the ectomycorrhizal association of Tuber aestivum Vittad. and Tuber brumale Vittad. in pecan after five years of cultivation in an orchard. The experiment was conducted in Santa Maria – Rio Grande do Sul, Brazil, in a pecan orchard planted with seedlings inoculated with these two species of truffles. The orchard was characterized in terms of soil physical and chemical properties and soil type. Initially non-inoculated plants, plants inoculated with Tuber aestivum (TA), and plants inoculated with Tuber brumale (TB) were evaluated for the percentage (%) of roots colonized by Tuber spp., other ectomycorrhizae, and non-mycorrhizal roots. A reduction in the colonization of both truffle species was observed five years after transplanting the seedlings to the orchard but they have the potential to maintain the ectomycorrhizal association with pecan seedlings. Ključne besede: Carya illinoinensis, ectomycorrhiza, truffle, tuber Objavljeno v DiRROS: 26.03.2024; Ogledov: 419; Prenosov: 201
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1538. Importance of habitat context in modelling risk maps for two established invasive alien plant species : the case of Ailanthus altissima and Phytolacca americana in Slovenia (Europe)Maarten De Groot, Erika Kozamernik, Janez Kermavnar, Marija Kolšek, Aleksander Marinšek, Andreja Nève Repe, Lado Kutnar, 2024, izvirni znanstveni članek Povzetek: Forests are important ecosystems that face threats from climate change and global environmental shifts, with invasive alien plant species being a significant concern. Some of these invasive species have already become established, while others are in the process of naturalisation. Although forests are a relatively stable ecosystem, extreme weather events increase their vulnerability to change, and clearings left after natural disturbances are particularly susceptible to invasion by alien plant species (IAPS). We created risk maps of two species that have spread rapidly in the last decade: American pokeweed (Phytolacca americana) and the tree of heaven (Ailanthus altissima). We prepared a generalised linear model based on the occurrence data collected within the LIFE ARTEMIS project. Eleven environmental variables were used to determine habitat characteristics. We constructed two models for each species: one covering the entirety of Slovenia and the other specifically for the forested areas in Slovenia, with the latter incorporating forest-specific variables (such as forest sanitation felling and monocultures). We observed the presence of both species at lower altitudes and in close proximity to water sources. American pokeweed tends to occur nearer to railways, while the presence of the tree of heaven is associated with areas lacking carbonate parent material and influenced by land use patterns. In forested areas, the occurrence of American pokeweed is influenced by forest habitat characteristics, such as disturbances caused by extreme weather events or the prevalence of Norway spruce monocultures. In contrast, the occurrence of the tree of heaven is influenced by more general environmental variables, such as altitude and proximity to railways. Consequently, we have generated risk maps for the entirety of Slovenia and separately for forested areas, both of which indicate similar levels of risk, particularly for the tree of heaven. The risk map for American pokeweed highlights numerous vulnerable areas, especially forest edges, which are highly susceptible to invasion. Furthermore, there is a higher likelihood of this species occurring in areas that have undergone sanitation felling. This study suggests that the production of risk maps of IAPS could be improved by focussing on habitat types and taking into account habitat-specific variables. This approach could enhance the early detection and management of these invasive species. Ključne besede: American pokeweed, tree of heaven, species distribution modelling, forests, forest disturbance, habitat suitability Objavljeno v DiRROS: 26.03.2024; Ogledov: 390; Prenosov: 1787
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