2641. Solvothermal synthesis of iron phosphides and their application for efficient electrocatalytic hydrogen evolutionTakwa Chouki, Manel Machreki, Saim Emin, 2020, izvirni znanstveni članek Opis: Abstract
In this paper, we present a solvothermal synthesis of iron phosphide electrocatalysts using a triphenylphosphine (TPP) precursor. The synthetic protocol generates Fe2P phase at 300 °C and FeP phase at 350 °C. To enhance the catalytic activities of obtained iron phosphide particles heat-treatments were carried out at elevated temperatures. Annealing at 500 °C under reductive atmosphere induced structural changes in the samples: (i) Fe2P provided a pure Fe3P phase (Fe3P−500 °C) and (ii) FeP transformed into a mixture of iron phosphide phases (Fe2P/FeP−500 °C). Pure Fe2P films was prepared under argon atmosphere at 450 °C (Fe2P−450 °C). The electrocatalytic activities of heat-treated Fe2P−450 °C, Fe3P−500 °C, and Fe2P/FeP−500 °C catalysts were studied for hydrogen evolution reaction (HER) in 0.5 M H2SO4. The HER activities of the iron phosphide catalyst were found to be phase dependent. The lowest electrode potential of 110 mV vs. a reversible hydrogen electrode (RHE) at 10 mA cm−2 was achieved with Fe2P/FeP−500 °C catalyst.
Ključne besede: Solvothermal synthesis, Iron phosphide, Electrocatalyst, Hydrogen evolution, Overpotential
Objavljeno v RUNG: 20.07.2020; Ogledov: 2680; Prenosov: 0
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2642. Determination of biogenic amine-forming potential of naturally occuring lactic acid bacteria (LAB) strains isolated from the grapes of Vitis vinifera cv. Refošk grape varietyJelena Topić, Lorena Butinar, Martina Bergant Marušič, Dorota Korte, Branka Mozetič Vodopivec, 2020, objavljeni povzetek znanstvenega prispevka na konferenci Opis: Biogenic amines are naturally occurring compounds that have been reported in variety of food, such as fish, meat, cheese, vegetables, and wines. When biogenic amines are formed by microorganisms such as lactic acid bacteria (LAB) they may have adverse effect on human health. The most common biogenic amines found in foodstuff are histamine, tyramine, putrescine and cadaverine. LAB are used as starters in the production of several foods and beverages. In wines they are used in malolactic fermentation, where the conversion of malic acid to lactic acid occurs. The aim of this work was to determine biogenic amine-forming capacity of indigenous LAB strains isolated from grapes which were PCR positive and screening medium positive for biogenic amines. Three methods for the confirmation of LAB biogenic amine-forming potential were developed and compared: HPLC-DAD and TLC methods both using derivatization agent dansyl chloride and enzymatic method using horseradish peroxidase (HRP) and diamine oxidase (DAO) enzymes. The applicability of methods was tested on the three known biogenic amine-producing LAB strains: 0006, 9809, 9906 (IOEB, France). The limit of detection (LOD) of the methods was <1 mg/L for HPLC-DAD, 5 mg/L for TLC and 25 mg/L for enzymatic method. Although the LODs between the proposed methods differed, all of the three methods confirmed BA-forming potential of the three strains. Furthermore, the proposed methods were applied for the analysis of three indigenous strains: MKBT-282 (BA+), MKBT-307 (BA-) and MKBT-325 (BA+). The positive or negative BA-forming potential was confirmed with all of the three proposed methods.
Ključne besede: lactic acid bacteria, biogenic amines, histamine, grape
Objavljeno v RUNG: 10.07.2020; Ogledov: 2992; Prenosov: 0
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2643. Soft set theory and hypercompositional algebrasHashem Bordbar, 2020, objavljeni povzetek znanstvenega prispevka na konferenci Opis: Some applications of soft set theory and fuzzy soft set theory (as a generalization of the soft set theory) in the decision-making problem were investigated by Maji et al. in [1].
The aim of this manuscript is to apply the concept of (fuzzy) soft set theory in some hypercompositional structure and especially hyper BCK-algebra. Some notations related to our hyperstructure are introduced and some examples are provided.
Ključne besede: Soft set theory, Hyper BCK-algebra, Fuzzy soft set theory.
Objavljeno v RUNG: 08.07.2020; Ogledov: 2409; Prenosov: 0
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2644. Lidar Observations of Mountain Waves During Bora EpisodesLonglong Wang, Marija Bervida, Samo Stanič, Klemen Bergant, William Eichinger, Benedikt Strajnar, 2020, objavljeni znanstveni prispevek na konferenci Opis: Airflows over mountain barriers in the Alpine region may give rise to strong, gusty downslope winds, called Bora. Oscillations, caused by the flow over an orographic barrier, lead to formation of mountain waves. These waves can only rarely be observed visually and can, in general, not be reliably reproduced by numerical models. Using aerosols as tracers for airmass motion, mountain waves were experimentally observed during Bora outbreak in the Vipava valley, Slovenia, on 24-25 January 2019 by two lidar systems: a vertical scanning lidar positioned just below the peak of the lee side of the mountain range and a fixed direction lidar at valley floor, which were set up to retrieve two-dimensional structure of the airflow over the orographic barrier into the valley. Based on the lidar data, we determined the thickness of airmass layer exhibiting downslope motion, observed hydraulic jump phenomena that gave rise to mountain waves and characterized their properties.
Ključne besede: Bora, mountain waves, lidar observations
Objavljeno v RUNG: 08.07.2020; Ogledov: 2745; Prenosov: 0
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2645. Polarization Raman Lidar for Atmospheric Monitoring in the Vipava ValleyLonglong Wang, Samo Stanič, William Eichinger, Xiaoquan Song, Marko Zavrtanik, 2020, objavljeni znanstveni prispevek na konferenci Opis: We report on the design, construction and performance of a polarization Raman lidar, built for atmospheric monitoring in the Vipava valley in SW Slovenia, a regional air pollution hot-spot where aerosols are expected to originate from a number of different sources. Its key features are automatized remote operation capability and indoor deployment, which provide high duty cycle in all weather conditions. System optimization and performance studies include the calibration of the depolarization ratio, merging of near-range (analog) and far-range (photon-counting) data, determination of overlap functions and validation of the retrieved observables with radiosonde data.
Ključne besede: polarization Ramal lidar, Vipava valley, atmospheric monitoring
Objavljeno v RUNG: 08.07.2020; Ogledov: 2987; Prenosov: 0
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2649. Zakaj velika okrogla rdeča čestitka in ne rdeča velika okrogla čestitka? Poskus razlage nezaznamovane stave pridevnikovFranc Marušič, Petra Mišmaš, Rok Žaucer, 2020, samostojni znanstveni sestavek ali poglavje v monografski publikaciji Opis: Nezaznamovana stava kakovostnih pridevnikov znotraj levega prilastka je univerzalna. Pridevniki za velikost, obliko in barvo se tako najpogosteje pojavljajo ravno v tem vrstnem redu. V slovnici lahko ta vrstni red opišemo na različne načine, vendar mora jezikoslovje pojasniti tudi, od kod ta vrstni red izhaja. Da bi odgovorili na to vprašanje,
se v prispevku omejimo na hipotezo, da je ta vrstni red osnovan na lastnostih nejezikovne kognicije. Predstavimo psihološki zaznavni eksperiment, s katerim smo hipotezo preverjali, in rezultate eksperimenta, ki hipotezo potrjujejo.
Ključne besede: kakovostni pridevniki, besedni red, izvor slovničnih pravil, slovnica in zunajjezikovna kognicija, tvorbena slovnica, kartografija
Objavljeno v RUNG: 01.07.2020; Ogledov: 2493; Prenosov: 0
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2650. En ali več morfem-ov?Marko Simonović, Petra Mišmaš, druga izvedena dela Opis: V predavanju se posvečava mnogim funkcijam morfema -ov-. Tega lahko namreč zasledimo v kontekstu besedotvornih morfemov, npr. v glagolih (hud-ov-a-ti (se)), v svojilnih pridevnikih (Janez-ov), skupnih imenih (grm-ov-je) ali v samostalnikih, izpeljanih iz samostalnikov (bank-ov-ec), in v vlogi oblikotvornega morfema (npr. jezik-ov.rod.mn). Vprašanje, na katerega odgovarjava v tem predavanju, je, ali gre v vseh teh (na prvi pogled nepovezanih) okoljih za več morfemov, ki so le naključno enakoglasni, oziroma ali lahko vse te pojavitve -ov- analiziramo kot en sam morfem. V predavanju se bova zavzela za slednjo možnost.
Skladno s tem v analizi, ki je postavljena v okvir razpršene morfologije, pristopa, nastalega v okviru tvorbene slovnice (Halle & Marantz 1993), zabriševa tradicionalno razmejitev med oblikotvornimi in besedotvornimi morfemi. Morfem -ov- se namreč v funkcijah, na katere se bova osredotočila v predavanju, tj. oblikotvorni -ov- (jezik-ov, grad-ov-i) in svojilni -ov- (npr. Janez-ov in zdravnik-ov/kralj-ev), obnaša kot morfem brez specifičnega pomena, katerega funkcija je odvisna od samega okolja, v katerem se pojavi.
Ključne besede: morfologija
razpršena morfologija
slovenščina
oblikotvorni morfemi
besedotvorni morfemi
Objavljeno v RUNG: 01.07.2020; Ogledov: 2457; Prenosov: 0
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