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51.
52.
Selective glucose oxidation to glucaric acid using bimetallic catalysts : lattice expansion or electronic structure effect?
Žan Lavrič, Janvit Teržan, Ana Kroflič, Janez Zavašnik, Joanna E. Olszówka, Štefan Vajda, Matej Huš, Miha Grilc, Blaž Likozar, 2024, izvirni znanstveni članek

Povzetek: Our study presents a comprehensive approach for the selective oxidation of glucose to glucaric acid (GA) by heterogeneous catalysis. We have synthesized and characterized Au/ZrO2, AuCu/ZrO2 and AuPt/ZrO2 catalysts using X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and oxygen pulse chemisorption (OPS) techniques. Combining experimental observations with in-depth density functional theory (DFT) studies, we found that bimetallic catalysts form alloys, which exhibit different characteristics than monometallic counterparts for the given reaction. We performed batch reactions, varying temperature and oxygen pressure, and used the data to construct a predictive microkinetic model. As it turned out, AuPt/ZrO2 showed the highest selectivity, yielding 32 % of GA at 100 °C and 30 barg O2. Our results provide valuable insights for the developing of efficient catalysts and point out the bottlenecks for the oxidation of glucose to GA.
Ključne besede: glucaric acid, glucose oxidation, catalyst characterization, density functional theory, microkinetic modelling
Objavljeno v DiRROS: 06.12.2023; Ogledov: 202; Prenosov: 117
.pdf Celotno besedilo (2,73 MB)
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53.
Pomen kakovosti pri delovanju citoloških laboratorijev za učinkovito presejanje
Ana Pogačnik, 2006, strokovni članek

Objavljeno v DiRROS: 05.12.2023; Ogledov: 143; Prenosov: 53
.pdf Celotno besedilo (166,89 KB)

54.
55.
Mining waste in circular economy - legislative aspect
Senko Pličanič, Ana Mladenovič, Alenka Mauko Pranjić, Petra Vrhovnik, 2020, izvirni znanstveni članek

Povzetek: One of the common European commitments is a transition towards a green circular economy in which waste is not discarded and considered to be just an environmental problem, but should be recognized as an important potential source of raw materials for industry. In a priority order in waste management activities, introduced by the Waste Directive in 2012, recycling is set just behind the waste prevention and reuse. Many types of waste can be recycled, the most perspective being construction, industrial and mining wastes. The latter are produced and disposed of at mine sites during the excavation and processing of ore and are extremely perspective due to large quantities and remaining of different metals, however still underutilized, with low recycling rate. Many mining wastes are inert and do not releases contaminants into environment, however, some of them are problematic and even require monitoring. Reprocessing of these wastes, which include beneficiation and sequential extraction of valuable metals in the first phase and recycling of residues in both structural and civil engineering in the second phase establishes a zero waste model with several benefits for economy, environment and society. Out of the South-East European countries, North Macedonia has great potential to establish this model. As a consequence of long mining tradition and abundant ore resources, there are many mining and metallurgical tailings, on the other hand vivid economy and numerous sinks for use of recycled materials in construction sector can accommodate these quantities. However, there are open questions in terms of administrative procedures and legislation. What are those obstacles that accompany the smooth establishment of the proposed model from a legislative point of view? This paper deals with the situation in North Macedonia, in terms of opportunities, legislative options and the need to adopt new legislation, taking also into account the current problems in this field in Europe.
Ključne besede: circular economy, zero-waste approach, mining waste, construction sector, legislation, krožno gospodarstvo, pristop ničelnega odpadka, rudarski odpadki, gradbeništvo, zakonodaja
Objavljeno v DiRROS: 04.12.2023; Ogledov: 193; Prenosov: 120
.pdf Celotno besedilo (435,68 KB)
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56.
Detoxified spent pot lining from aluminum production as (alumino-)silicate source for composite cement and autoclaved aerated concrete
Arne Peys, Mateja Košir, Ruben Snellings, Ana Mladenovič, Liesbeth Horckmans, 2021, izvirni znanstveni članek

Povzetek: New sources of supplementary cementitious materials (SCMs) are needed to meet the future demand. A potential new source of SCM is spent pot lining, a residue from aluminum production. The present work showed that the refined aluminosilicate part of spent pot lining (SPL) has a moderate chemical reactivity in a cementitious system measured in the R3 calorimetry test, comparable to commercially used coal fly ash. The reaction of SPL led to the consumption of Ca(OH)2 in a cement paste beyond 7 days after mixing. At 28 and 90 days a significant contribution to strength development was therefore observed, reaching a relative strength, which is similar to composite cements with coal fly ash. At early age a retardation of the cement hydration is caused by the SPL, which should most likely be associated with the presence of trace amounts of NH3. The spent pot lining is also investigated as silica source for autoclaved aerated concrete blocks. The replacement of quartz by spent pot lining did not show an adverse effect on the strength-density relation of the lightweight blocks up to 50 wt% quartz substitution. Overall, spent pot lining can be used in small replacement volumes (30 wt%) as SCM or as replacement of quartz (50 wt%) in autoclaved aerated concrete blocks.
Ključne besede: spent pot lining, construction materials, recycling, autoclaved aerated conctrte, supplementary cementitious material
Objavljeno v DiRROS: 04.12.2023; Ogledov: 189; Prenosov: 82
.pdf Celotno besedilo (15,66 MB)
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57.
Citodiagnostika netipljivih lezij v dojkah
Ana Pogačnik, Margareta Strojan Fležar, 2004, objavljeni znanstveni prispevek na konferenci

Povzetek: Izhodišča. Aspiracijska biopsija s tanko iglo (ABTI) je uveljavljena metoda zadiagnostiko sprememb v dojki. V pričujoči študiji smo želeli ugotoviti zanesljivost ultrazvočno (UZ) ali rentgensko (RTG) vodene ABTI za diagnostiko netipljivih lezij v dojki na podlagi cito-histološke korelacije in izračunati občutljivost, specifičnost, napovedno veljavnost pozitivne in negativne diagnoze. Bolniki in metode. V retrospektivno študijo smo vključili 179 žensk,pri katerih je bila v letu 2003 izvršena UZ ali/in RTG vodena ABTI netipljive lezije v dojki, ki je bila kasneje histološko opredeljena na vzorcubiopsije z debelo iglo, vodeni ekscizijski biopsiji ali na kirurškem resektatu. Rezultati. V 66 (36,8%) primerih je bil histološko dokazan karcinom, v 113 (63,1%) primerih pa benigna lezija. Citopatološke diagnoze v skupini karcinomov so bile: karcinom v 41 primerih (62,1%), sumljivo za karcinom v 12 (18,2%), napačno negativna diagnoza v 3 (4,5%), v 10 (15%) primerih pa niso dobili dovolj materiala za diagnozo. Zaključki. V skupini benignih lezij smo iz vzorca ABTI postavili pravilno negativno diagnozo v 55 primerih (48,7%), napačno sumljivo v 18 (15,9%), napačno pozitivno diagnozo v enem primeru (0,88%) in v 39 (34,5%) primerih nismo dobili dovolj materiala zadiagnozo. Občutljivost metode v naši študiji je bila 91%, specifičnost 98%, napovedna veljavnost pozitivne diagnoze 97,6% in napovedna veljavnost negativne diagnoze 94,8 %.
Objavljeno v DiRROS: 01.12.2023; Ogledov: 154; Prenosov: 55
.pdf Celotno besedilo (323,74 KB)

58.
Not another hillshade: alternatives which improve visualizations of bathymetric data
Ana Novak, Sašo Poglajen, Marko Vrabec, 2023, izvirni znanstveni članek

Povzetek: Increasing awareness of the importance of effective communication of scientific results and concepts, and the need for more accurate mapping and increased feature visibility led to the development of novel approaches to visualization of high-resolution elevation data. While new approaches have routinely been adopted for land elevation data, this does not seem to be the case for the offshore and submerged terrestrial realms. We test the suitability of algorithms provided by the freely-available and user-friendly Relief Visualization Toolbox (RVT) software package for visualizing bathymetric data. We examine the algorithms optimal for visualizing the general bathymetry of a study area, as well as for highlighting specific morphological shapes that are common on the sea-, lake- and riverbed. We show that these algorithms surpass the more conventional analytical hillshading in providing visualizations of bathymetric data richer in details, and foremost, providing a better overview of the morphological features of the studied areas. We demonstrate that the algorithms are efficient regardless of the source data type, depth range, resolution, geographic, and geological setting. The summary of our results and observations can serve as a reference for future users of RVT for displaying bathymetric data.
Ključne besede: bathymetry, RVT, visualization, hillshade, geomorphology, marine geology, multibeam
Objavljeno v DiRROS: 01.12.2023; Ogledov: 198; Prenosov: 64
.pdf Celotno besedilo (15,49 MB)

59.
In situ consideration of resistance of bridge girder according to EC2 with AEM
Ana Brunčič, Andrej Štrukelj, Maja Kreslin, Andrej Anžlin, Aljoša Šajna, 2023, objavljeni znanstveni prispevek na konferenci

Povzetek: The paper presents a case study of a considerably cracked and degraded bridge in Slovenia: with the implementation of in-situ measurements under bending and shear and the use of a non-destructive acoustic emission technique. Despite the existing crack system, the latter was able to detect microstructural changes. These were characterised by low values of average frequency (AF), as well as lower values of the rise time-amplitude ratio (RA), and energy. A correlation between shear capacity and acoustic activity was observed. This promises to expand the use of AE in the process of assessing of the load-bearing capacity of existing concrete structures.
Ključne besede: shear resistance, shear crack, crack width, acoustic emission (AE) parameters, bridge girder, stiffness, elasticity, damage evaluation
Objavljeno v DiRROS: 28.11.2023; Ogledov: 192; Prenosov: 104
.pdf Celotno besedilo (1,08 MB)
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60.
Vloga dermatologa v preventivi malignih tumorjev kože
Ana Benedičič-Pilih, Igor Bartenjev, 1999, pregledni znanstveni članek

Povzetek: Preventiva malignih tumorjev kože (MTK) obsega vrsto dejavnosti, ki imajo namen preprečiti razvoj teh bolezni, katerih incidenca v zadnjih desetletjih vztrajno narašča po svetu in pri nas. Dermatolog ima pomembno vlogo ne le pri diagnostiki in zdravljenju različnih vrst MTK, temveč tudi pri individualnem svetovanju glede zaščite kože pred delovanjem različnih kancerogenov v okolju ter pri razvoju zdravstvene politike v smeri razumevanja in sprejemanja za zdravje kože potrebnih sprememb v stališčih in obnašanju do škodljivih vplivov okolja, ki sodelujejo pri razvoju MTK.
Objavljeno v DiRROS: 27.11.2023; Ogledov: 151; Prenosov: 49
.pdf Celotno besedilo (347,48 KB)

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