1. Investigating the synergistic impact of freeze-thaw cycles and deicing salts on the properties of cementitious composites incorporating natural fibers and fly ashIldikó Merta, Vesna Zalar Serjun, Alenka Mauko Pranjić, Aljoša Šajna, Mateja Štefančič, Bojan Poletanovic, Farshad Ameri, Ana Mladenović, 2025, izvirni znanstveni članek Povzetek: In cold climates, concrete structures confront durability challenges due to harsh conditions. This study evaluates the effects of incorporating natural fibers, such as hemp and flax fibers (at 1 vol%), and partially replacing cement with fly ash (at 25 and 50 wt%) on the properties of cementitious composites subjected to accelerated aging under freeze-thaw cycles and deicing salts. Findings reveal that natural fibers enhance the freeze-thaw resistance, reducing deterioration (scaling) to 5-8% after 56 cycles. When mortars were subjected to accelerated freeze-thaw cycles, the compressive strength of plain mortar significantly decreased (up to 57%). However, adding natural fibers to the matrix substantially reduced its compressive strength loss. In the case of flexural strength, plain mortars experienced 33% loss, while hemp, flax, and polypropylene fiber mortars showed only 13%, 23%, and 10% losses, respectively. Furthermore, mortars experience a notable enhancement in their energy absorption capacity when reinforced with natural fibers, particularly with hemp fibers (up to 348% higher than plain mortar). Under harsh conditions, hemp and flax-reinforced mortars, with 25wt% fly ash replacement, lose the compressive strength significantly however still demonstrate an alternative to synthetic fibers in terms of flexural strength. Even with 25wt% of fly ash, mortars with natural fiber reinforcement display significantly superior energy absorption capacities compared to plain mortars (up to 48%).
Ključne besede: cementitious composites, natural fibers, freeze-thaw cycles, mechanical properties, mass loss, fly ash
Objavljeno v DiRROS: 23.12.2024; Ogledov: 0; Prenosov: 0
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2. Strategic decisions : how good does it fit the decision-making process into the strategic management process?Edvard Kolar, Matej Tušak, Petra Robnik, Roberto Biloslavo, 2024, izvirni znanstveni članek Povzetek: The complicated dance between the decision-making (hereinafter: DM) process, which is shaped by the individual psychological constructs and internal cognitive processes, and the methodological process of strategic management (hereinafter: SMP), which can be understood as a framework that defines decision context, raises pertinent questions about their coherence. The purpose of this study is to propose an integrative model of the strategic decision-making process (hereinafter: SDM), which links the cognitive processes of decision-makers with the rigour of strategic management and identifies and mitigates potential risks at each stage of the holistic process. To design the research, we used the "model paper" approach which seeks to build a theoretical framework that predicts relationships between research concepts. The developed comprehensive model connects four independent concepts, creating a holistic framework for SDM in organizations. The comprehensive model reveals a high degree of consistency between the SMP, knowable decision-making cycle and cognitive processes. Throughout the entire process, decision-makers need to be mindful of the interplay between System 1 and System 2 thinking. While System 1 thinking may provide quick insights and initiate creative thinking, it is important to complement it with the deliberate and analytical reasoning of System 2 thinking, which can be supported by a proper application of different strategic management tools and methods.
Ključne besede: strategic management process, decision making process, integrative concept, strategic decision making, system 1 and 2 thinking
Objavljeno v DiRROS: 23.12.2024; Ogledov: 1; Prenosov: 0
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3. Influence of smoking method and anatomical location on the content of polycylcic aromatic hydrocarbons in Turopooje hamDanijel Karolyi, Sandra Petričević, Zoran Luković, Dubravko Škorput, Ana Kaić, Krešimir Salajpal, Marjeta Čandek-Potokar, 2024, izvirni znanstveni članek Ključne besede: dry-cured ham, meat smoking, PAH compounds, muscle, Turopolje pig
Objavljeno v DiRROS: 23.12.2024; Ogledov: 2; Prenosov: 2
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4. Sedem desetletij metasekvoje (Metasequoia glyptostroboides Hu et Cheng) v SlovenijiIza Petek, Gregor Božič, Dušan Jurc, Kristjan Jarni, Robert Brus, 2024, pregledni znanstveni članek Povzetek: Metasekvoja (Metasequoia glyptostroboides Hu et Cheng) je ena najpozneje odkritih drevesnih vrst na Zemlji in hkrati zelo stara vrsta, ki se morfološko skozi milijone let skoraj ni spremenila. Odkrita je bila šele sredi 20. stoletja na Kitajskem, le nekaj let za tem, ko so znanstveniki odkrili njene fosilne ostanke in predvidevali, da gre za izumrlo vrsto. Po odkritju se je o metasekvoji veliko govorilo in pisalo, sadili so jo po vsem svetu z namenom preučevanja, saj je bilo odkritje živih osebkov senzacija za ves botanični svet. Danes se je v luči podnebnih sprememb in ob iskanju novih možnosti za večjo odpornost gozda metasekvoja kot potencialno uporabna vrsta zopet znašla pod drobnogledom. Njeno močno užlebljeno deblo in obstojnost odmrlih vej lahko predstavljajo težavo pri obdelavi njenega proti glivam sicer zelo odpornega lesa, hkrati pa zaradi edinstvenega videza deluje izredno estetsko predvsem v urbanem okolju. Kot gospodarsko vrsto jo uporabljajo ponekod na Kitajskem, v Evropi jo sadijo predvsem v testnih nasadih in v urbanem okolju. V preglednem prispevku je po sedmih desetletjih prisotnosti metasekvoje v Sloveniji podrobneje predstavljena zgodovina njenega odkrivanja, dosedanja uporaba in ocenjen je njen prihodnji potencial.
Ključne besede: Slovenija, Metasequoia glyptostroboides, zgodovina, odkritje, lastnosti, drevesne vrste
Objavljeno v DiRROS: 22.12.2024; Ogledov: 123; Prenosov: 17
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5. Unveiling the potential of ▫$(CoFeNiMnCr)_3O_4$▫ high-entropy oxide synthesized from CoFeNiMnCr high-entropy alloy for efficient oxygen-evolution reactionBarbara Ljubec Božiček, Jitka Hreščak, Monika Kušter, Janez Kovač, Iztok Naglič, Boštjan Markoli, Barbara Šetina, Martin Šala, Sandra Drev, Živa Marinko, Miran Čeh, Belisa Alcantara Marinho, 2024, izvirni znanstveni članek Povzetek: Electrochemical water-splitting is a promising green technology for the production of hydrogen. One of the bottlenecks, however, is the oxygen evolution half-reaction (OER), which could be overcome with the development of a suitable electrocatalyst. Recently, non-noble metal, high-entropy oxides (HEO) have been investigated as potential OER electrocatalysts, but complex synthesis approaches that usually produce the material in powder form limit their wider utilization. Here, an innovative synthesis strategy of formulating a nanostructured (CoFeNiMnCr)3O4 HEO thin film on a CoFeNiMnCr high entropy alloy (HEA) using facile electrochemical and thermal treatment methods is presented. The CoFeNiMnCr HEA serves as exceptional support to be electrochemically treated in an ethylene glycol electrolyte with ammonium fluoride to form a rough and microporous structure with nanopits. The electrochemically treated CoFeNiMnCr HEA surface is more prone to oxidation during a low-temperature thermal treatment, leading to the growth of a spinel (CoFeNiMnCr)3O4 HEO thin film. The (CoFeNiMnCr)3O4 HEO exhibits a superior overpotential of 341 mV at 10 mA cm−2 and a Tafel slope of 50 mV dec−1 along with remarkable long-term stability in alkaline media. The excellent catalytic activity and stability for the OER can serve as a promising platform for the practical utilization of (CoFeNiMnCr)3O4 HEO.
Ključne besede: electrochemical water-spliting, electrocatalysts
Objavljeno v DiRROS: 20.12.2024; Ogledov: 49; Prenosov: 16
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6. Combined cytogenetic and molecular methods for taxonomic verification and description of Brassica populations deriving from different originsFrançois Lefévre, Houria Hadj-Arab, Fella Aissiou, Claudia Bartoli, Giuseppe Bazan, Matéo Boudet, Lydia Bousset-Vaslin, Marwa Chouikhi, Olivier Coriton, Gwénaelle Deniot, Vladimir Meglič, Barbara Pipan, Lovro Sinkovič, 2024, izvirni znanstveni članek Ključne besede: wild populations, landraces, Brassica, genetic diversity, taxonomic verification
Objavljeno v DiRROS: 20.12.2024; Ogledov: 51; Prenosov: 9
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7. Landscape permeability for ecological connectivity at the macro-regional level : The Continuum Suitability Index and its practical implicationsPeter Laner, Christian Rossi, Rachel Luethi, Filippo Favilli, Irena Bertoncelj, Guido Plassmann, Rudolf Michael Haller, 2024, izvirni znanstveni članek Ključne besede: strategic connectivity areas, structural connectivity, sensitivity analysis, fragmentation use, land-use, Alps Dinaric Mountains
Objavljeno v DiRROS: 20.12.2024; Ogledov: 54; Prenosov: 11
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8. Assessment of extracellular particles directly in diluted plasma and blood by interferometric light microscopy : a study of 613 human and 163 canine samplesBoštjan Korenjak, Armando Tratenšek, Matevž Arko, Anna Romolo, Matej Hočevar, Matic Kisovec, Maxence Berry, Apolonija Bedina Zavec, David Drobne, Tomaž Vovk, Aleš Iglič, Alenka Nemec Svete, Vladimira Erjavec, Veronika Kralj-Iglič, 2024, izvirni znanstveni članek Ključne besede: extracellular particles, extracellular vesicles, exosomes, membrane vesiculation, platelets, blood products, platelet-rich plasma, liquid biopsy, membrane enclosed, drug delivery
Objavljeno v DiRROS: 20.12.2024; Ogledov: 53; Prenosov: 16
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9. Influence of surface preparation of aluminum alloy AW-5754 and stainless steel X5CRNI18-10 on the properties of bonded jointsNataša Zdravković, Damjan Klobčar, Dragan Milčić, Matevž Zupančič, Borut Žužek, Miodrag Milčić, Aleksija Ðurić, 2024, izvirni znanstveni članek Povzetek: Adhesive bonding has proven to be a reliable method of joining materials, and the development of new adhesives has made it possible to use bonding in a variety of applications. This article addresses the challenges of bonding metals such as the aluminum alloy EN AW-5754 and the stainless steel X5CrNi18-10. In this study, the effects of laser cleaning and texturing on the surface properties and strength of two bonded joints were investigated and compared with mechanical preparation (hand sanding with Scotch-Brite and P180 sandpaper). The bonded joints were tested with three different epoxy adhesives. During the tests, the adhesion properties of the bonded surface were determined by measuring the contact angle and assessing the wettability, the surface roughness parameters for the different surface preparations, and the mechanical properties (tensile lap-shear strength). Based on the strength test results, it was found that bonded joints made of stainless steel had 16% to 40% higher strength than aluminum alloys when using the same adhesive and surface preparation. Laser cleaning resulted in maximum shear strength of the aluminum alloy bond, while the most suitable surface preparation for both materials was preparation with P180 sandpaper for all adhesives.
Ključne besede: adhesive bonding, surface preparation, aluminum alloy AW-5754, stainless steel X5CrNi18-10, epoxy adhesives
Objavljeno v DiRROS: 20.12.2024; Ogledov: 44; Prenosov: 18
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10. On the thermal stability of multilayer optics for use with high X-ray intensitiesMargarita Zakharova, Zlatko Rek, Božidar Šarler, Saša Bajt, 2024, izvirni znanstveni članek Povzetek: High-intensity X-ray free electron laser (XFEL) beams require optics made of materials with minimal radiation absorption, high diffraction efficiency, and high radiation hardness. Multilayer Laue lenses (MLLs) are diffraction-based X-ray optics that can focus XFEL beams, as already demonstrated with tungsten carbide/silicon carbide (WC/SiC)-based MLLs. However, high atomic number materials such as tungsten strongly absorb X-rays, resulting in high heat loads. Numerical simulations predict much lower heat loads in MLLs consisting of low atomic number Z materials, although such MLLs have narrower rocking curve widths. In this paper, we first screen various multilayer candidates and then focus on Mo2C/SiC multilayer due to its high diffraction efficiency. According to numerical simulations, the maximum temperature in this multilayer should remain below 300°C if the MLL made out of this multilayer is exposed to an XFEL beam of 17.5 keV photon energy, 1 mJ energy per pulse and 10 kHz pulse repetition rate. To understand the thermal stability of the Mo2C/SiC multilayer, we performed a study on the multilayers of three different periods (1.5, 5, and 12 nm) and different Mo2C to SiC ratios. We monitored their periods, crystallinity, and stress as a function of annealing temperature for two different heating rates. The results presented in this paper indicate that Mo2C/SiC-based MLLs are viable for focusing XFEL beams without being damaged under these conditions.
Ključne besede: x-ray optics, multilayer Laue lens, thermal stability, numerical simulation
Objavljeno v DiRROS: 20.12.2024; Ogledov: 46; Prenosov: 17
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