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Influence of Pr content on structural evolution of doped ceria-based high-entropy oxides
No full textHigh-entropy fluorite oxides offer exceptional tunability of structure and functionality through controlled multi-cation substitution. In this work, Ce-Zr-Pr-Sm-Eu-based high-entropy oxides, with systematically varied Pr content, were synthesized using a modified sol–gel citrate method to investigate the influence of Pr incorporation on lattice structure, defect formation, and photocatalytic performance. All compositions crystallized in a single-phase cubic fluorite structure, where increasing Pr concentration induced gradual lattice expansion and microstrain due to the substitution of larger Pr3+ ions. Morphological and surface analyses revealed porous nanostructures at moderate Pr levels, while excessive Pr promoted densification and reduced surface accessibility. Spectroscopic studies confirmed the coexistence of Pr3+/Pr4+ and Ce3+/Ce4+ redox couples, strong 4f–2p orbital hybridization, and enhanced defect-related electronic states that narrowed the optical bandgap. The optimized Pr-doped composition exhibited almost 100% degradation of methylene blue under UV light over 30 min, untypical for semiconductors with a narrower bandgap, and is enabled by efficient charge separation and redox cycling between Ce and Pr centers
Search for ultra-high-energy neutrons from Galactic sources with the Pierre Auger Observatory
No full textDeflections in the propagation of charged ultra-high-energy cosmic rays (UHECRs) caused
by magnetic fields make the identification of their sources challenging. On the other hand,
the arrival directions at Earth of neutrons point directly to their origin. The emission of UHECRs
from a source is expected to be accompanied by the production of neutrons in its vicinity
through interactions with ambient matter and radiation. Since free neutrons with energy E
travel a mean distance 9.2 (E/EeV) kpc before decaying, a neutron flux in the EeV range could
be detected on Earth from sources of UHECRs in our Galaxy.
Using cosmic-ray data from Phase I of the Surface Detector of the Pierre Auger Observatory,
we search for neutron fluxes from Galactic candidate sources. We select more than 1000
objects of astrophysical interest, stacking them into target sets. The targets all have declination
within the exposure of the Observatory, ranging from −90° up to +45° for energies above 1 EeV
(and up to +20° for energies down to 0.1 EeV). Given that a neutron air shower is
indistinguishable from a proton one, there is a significant background due to cosmic rays.
A neutron flux from the direction of a candidate source would be identified by a celestial density
of events that significantly exceeds the expected density of cosmic rays for that direction.
No significant excess is found at any tested target direction, and an upper limit on the neutron
flux is calculated for each candidate source
Podatkovna zbirka rezultatov naloge presoje sprejemljivosti stavkov, ki so permutacijske različice osnovnega besednega reda v ruščini
No full textTabele predstavljajo številčne ocene sprejemljivosti stavkov, ki so permutacijske različice osnovnega stavka s pomenom »Mama bo brala zanimivo knjigo« v tabeli "baza podatkov1", osnovnega stavka s pomenom »Kritik bo gledal dokumentarni film« v tabeli "baza podatkov2" ter osnovnega stavka s pomenom »Delavci bodo gradili novo bolnišnico« v tabeli "baza podatkov3". Ocene sprejemljivosti so bile podane na Likertovi lestvici od 1 (popolnoma nesprejemljivo) do 5 (popolnoma sprejemljivo)
Napredne sklopljene kromatografske tehnike za določanje glavnih metabolitov v (brez)alkoholnih pijačah
No full textNamenska kolona HPLC za ciljno analizo (npr. pri analizi sladkorja z uporabo stacionarnih faz HILIC) omogoča hitro in zelo točno določanje fruktoze, glukoze in saharoze v katerem koli homogenem tekočem vzorcu mošta, vina ali ciderja. Kolona HPLC na osnovi polimerne stacionarne faze (več različnih mehanizmov hkratnega ločevanja) omogoča tudi hitro in sočasno analizo več spojin v eni analizi (sladkorji, alkoholi in organske kisline), vendar pa je točnost določanja sladkorjev in nekaterih organskih kislin slaba. Po drugi strani je mogoče natančno določiti metanol, etanol, glicerol, ocetno, jantarno in piruvično kislino, medtem ko teh spojin ni mogoče določiti z omenjeno kolono HILIC. Kompromis med visoko točnostjo in številom parametrov za nadzor kakovosti, ki jih je mogoče določiti hkrati, je mogoče doseči z dvema zaporedno vezanima kolonama na osnovi reverzne faze. Zato je reverznofazni sistem HPLC-UV/RI še posebej uporaben za hitro, preprosto in točno določanje glavnih kemijskih parametrov pri spremljanju alkoholnih in malolaktičnih fermentacij
Dogodki plimskih raztrganj, kvazi-periodični izbruhi in tranzientna spremenljivost: karakterizacija in modeliranje v vidni in ultravijolični svetlobi
No full textVtisi rezidentk na Humanistični rezidenci Branislave Sušnik v Medvodah
No full textPredstavljeni so pogledi Glorie Scappini, Yanine Vidal in Agustine de Vera
Modeling gender variation in Russian indeclinable nouns
No full textIn this paper, we provide an analysis of the grammatical gender of 131 inanimate
indeclinable Russian nouns based on the data from the General Internet Corpus
of the Russian Language. We demonstrate that most nouns show substantial variation,
being used in two or even in all three genders: masculine, feminine, and neuter.
We identify several factors affecting this, primarily the gender of the semantic analogy
noun and the root-final vowel. We argue that these data can be used to compare
several major morphological frameworks and conclude that some approaches, namely
optimality-theoretic probabilistic ones, are better suited to account for them. We also
compare different models within the chosen set of approaches and show that the hierarchical
Maximum Entropy (MaxEnt) models are superior to the classical MaxEnt
models