131. Remediation of contaminated soil by red mud and paper ashPrimož Oprčkal, Ana Mladenovič, Nina Zupančič, Janez Ščančar, Radmila Milačič, Vesna Zalar Serjun, 2020, izvirni znanstveni članek Povzetek: Remediation of contaminated soil can be performed by using various techniques, which must be adequately tailored for each specific case. The aim of this research is to critically evaluate the potential use of red mud and paper ash and a combination of the two as immobilization additives for the remediation of contaminated soil from one of the most polluted sites in Slovenia. The proposed procedure involves the preparation of geotechnical composites made from contaminated soil and mixed with 25 wt% of immobilization additives and an optimal quantity of water to achieve consistency, at which maximum compaction according to the Proctor Compaction Test procedure can be achieved. The results reveal a positive, time-dependent trend for the immobilization of potentially toxic elements in the composite with paper ash, because of the formation of the new hydration products with potentially toxic elements. In a composite containing only red mud, potentially toxic elements were immobilized by sorption mechanisms with no general time-dependent trends. The composite with a combination of additives demonstrates the remediation characteristics of both red mud and paper ash. Using this approach excavated contaminated soil, red mud and paper ash can be successfully recycled in the proposed composites, which can be beneficially used in situ for rehabilitation of contaminated sites. Nevertheless, mobilization of some potentially toxic elements at high pHs may represent a limiting factor and has to be taken into the consideration when a combination of red mud and paper ash is used as immobilization additive.
Ključne besede: red mud, paper ash, contaminated soil, potentially toxic elements, geotechnical composites
Objavljeno v DiRROS: 31.08.2023; Ogledov: 352; Prenosov: 270
 Celotno besedilo (2,28 MB)
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132. Depassivation and repassivation of stainless steels by stepwise pH changeEmir Mujanović, Bojan Zajec, Andraž Legat, Tadeja Kosec, Janez Kovač, Gregor Mori, Stefan Hönig, Gerald Zehethofer, 2020, izvirni znanstveni članek Povzetek: Immersion tests with different stainless steels have been performed, while the pH was stepwise decreased and then increased again. During 8.5-day exposure, the depassivation and repassivation pH values as a function of pitting resistance equivalent number were determined. There is always a gap between both pH values (depassivation and repassivation), indicating that for every steel, there are conditions where an existing passive layer can be maintained but cannot be rebuilt after depassivation. In such environments, the passive layer is thicker, consisting mainly of molybdenum and iron rich oxides, while chromium is dissolved. Usually, depending on conditions, the passive layer is more chromium-rich, especially the inner layer. This is relevant, for example, for acidizing jobs in oil and gas industry, proving that repassivation after acidizing will happen promptly, when the pH is increased again.
Ključne besede: stress corrosion cracking, surface finish impact, tapered tensile specimen, autoclave, accelerated testing, light water nuclear reactor, critical threshold stress
Objavljeno v DiRROS: 30.08.2023; Ogledov: 348; Prenosov: 175
Celotno besedilo (4,01 MB)
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133. Environmental impacts of mixed aggregates for use in unbound layers in road constructionMetka Gostečnik, Predrag Šinik, Ana Mladenovič, Janez Ščančar, Radmila Milačič, 2020, izvirni znanstveni članek Povzetek: During carbon steel manufacturing, large amounts of electric arc furnace (EAF) slag are generated. EAF slag, if properly treated and processed into aggregate, is an alternative source of high-quality material, which can substitute the use of natural aggregates in most demanding applications in the construction sector, mostly for wearing asphalt courses. In this screening process of high-quality aggregates, a side material with grainsize 0/32 mm is also produced, which can be used as an aggregate for unbound layers in road construction. In this study, the environmental impacts of slag aggregate (fraction 0/32 mm) were evaluated in mixed natural/slag aggregates. Different mixtures of natural/slag aggregates were prepared from aged (28 days) and fresh slag, and their environmental impacts were evaluated using leaching tests. It was shown that among the elements, chromium (Cr) was leached from some mixed aggregates in quantities that exceeded the criterion for inert waste. The data from the present investigation revealed that mixed aggregates, prepared from aged slag (fraction 0/32 mm) and natural stone in the ratio 10/90, are environmentally acceptable and can be safely used in unbound materials for road construction.
Objavljeno v DiRROS: 30.08.2023; Ogledov: 300; Prenosov: 149
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134. Mikološka flora in entomofavna v obmejnih gozdovih okoli Lokve in KozineStana Hočevar, Janez Titovšek, 1969, strokovni članek Ključne besede: gozdarstvo, gozdovi, mikologija, entomologija, vegetacija, glive, žuželke
Objavljeno v DiRROS: 29.08.2023; Ogledov: 444; Prenosov: 115
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138. Vegetacijske in talne razmere v izbranih gozdovih GGE Marija Reka : (delavnica Javne gozdarske službe in projekta Life-IP Natura.SI na OE ZGS Celje)Valerija Babij, Lado Kutnar, Aleksander Marinšek, Matej Tajnikar, Egon Vočko, Janez Černec, 2023, druge monografije in druga zaključena dela Ključne besede: vegetacija, tla, rastišče, ekologija gozda, delavnice, Javna gozdarska služba, Slovenija, fitocenologija, gozdne združbe, gozdni rastiščni tipi
Objavljeno v DiRROS: 17.08.2023; Ogledov: 363; Prenosov: 146
Celotno besedilo (8,02 MB) |
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140. Effect of belowground deployment of entomopathogenic fungus Metarhizium brunneum on strawberry plants and aboveground pestsJaka Razinger, Darinka Koron, Špela Modic, Eva Praprotnik, Primož Žigon, Uroš Žibrat, Matej Knapič, Janez Lapajne, Andrej Vončina, Lovro Sinkovič, Nika Cvelbar Weber, 2023, drugi znanstveni članki Ključne besede: biological control, integrated pest management, agricultural entomology, entomopathogenic fungi, hyperspectral imaging, remote sensing, plant-microbe-pest interaction, plant physiology, rhizosphere competence
Objavljeno v DiRROS: 27.07.2023; Ogledov: 356; Prenosov: 0 |
