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Surface characterization of ▫▫ oxide catalyst supports by physisorption and chemisorption methods
No full textMetal oxides such as zinc oxide, aluminum oxide (Al2O3), and gallium oxide (Ga2O3) are
pivotal as catalytic supports, particularly in reactions like CO2 hydrogenation, where they
influence both the activity and selectivity of the catalytic process [1]. The surface characteristics
of metal oxides, including their acidity, basicity, and metal–support interactions, are key factors
governing catalytic activity, selectivity, and stability, particularly in CO2 hydrogenation
processes. Tailoring these properties through the design of mixed metal oxides, enables
improved dispersion of active metal species, enhanced thermal stability, and precise modulation
of surface reactivity. Such modifications facilitate a deeper understanding of reaction
mechanisms by influencing the nature, distribution, and accessibility of active sites [2, 3, 4, 5].
We present the preparation of ZnM mixed metal oxide (M = Al3+, Ga3+, In3+) catalyst supports
via hydrothermal treatment of a mixed metal hydroxide precursor. The hydroxides were
synthesized via co-precipitation and subsequently thermally treated at various temperatures
(400 °C, 550 °C, 700 °C, 850 °C, and 1000 °C) to obtain the corresponding mixed metal oxides
with varying degrees of crystallinity. Temperature-dependent changes in crystallinity and
surface area were evaluated using XRD and BET analysis, revealing increased crystallinity and
a progressive decrease in surface area with rising calcination temperature. Morphological and
elemental analyses were conducted using scanning electron microscopy (SEM), transmission
electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDS), confirming
homogeneous distribution of metal ions. Surface acidity was investigated using pyridine
temperature-programmed desorption (TPD), and surface interactions with CO₂ were assessed
via in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) CO2
adsorption/desorption studies. The findings highlight t
Možnost razvoja naravoslovnih dejavnosti in tematskih oblik turizma na Bobovških jezerih
No full textReprezentacije in konfiguracije multikulturalizma v delu Vrnitev v rodni kraj Louisa Adamiča
No full textIn his work The Native’s Return (1934), Louis Adamič navigates the complexities of multiculturalism, drawing on his experiences in both the polyethnic United States and the multinational Kingdom of Yugoslavia. The article explores Adamič’s multicultural awareness in his writings on Yugoslavia’s customs, social relations, culture, and politics. This analysis will provide insightful perspectives on Adamič’s representation of Yugoslavia in the American public sphere and how his American experience influenced his views on Yugoslav cultural and political situations
Red ball
No full textDiplomska naloga obravnava uporabo mitologije zahodnih in vzhodnih držav. Predstavlja
mitologijo v animaciji ter razloži njen pomen pri dojemanju smrti in duhovnosti različnih
civilizacij. Razloži uporabo mitologije v duhovnem svetu ter primerja mitologijo in vero.
Naloga primerja strukturo zgodb v vzhodnih in zahodnih kulturah. Osredotoči se na zelo znano
Aristotelovo tridelno strukturo ter vzhodno strukturo, imenovano Kishotenketsu. Spoznamo
nekaj mitoloških bitij različnih narodov.
Analiza mitov z Japonske, Koreje, Kitajske ter iz slovanske mitologije pokaže, kako različne
kulture vplivajo na razvoj mitoloških zgodb, ki so si lahko tudi zelo podobne. Naloga prav tako
opiše nekaj zelo znanih animacij ter jih primerja z uporabo mitologije v teh.
V praktičnem delu naloga opisuje razvoj zgodbe ter filma Rdeča žoga. Zgodba sledi likoma
Naliju in Hel, ki se morata soočiti z zlom. Predstavljeni so vsi procesi izdelave animiranega
filma. Razvoj se začne s predprodukcijo in zaključi s postprodukcijo, opisani pa so tudi vsi
tehnični izzivi, ki so nastali med izdelavo animiranega filma.This thesis explores the use of mythology in Western and Eastern countries. It presents
mythology in animation and explains its significance in understanding death and spirituality
across various civilizations. It discusses the use of mythology in the spiritual realm and
compares mythology with religion. The thesis also compares story structures in Eastern and
Western cultures, focusing on the well known Aristotelian three act structure and the Eastern
narrative structure called Kishotenketsu. Several mythological creatures from different cultures
are introduced.
An analysis of myths from Japan, Korea, China, and Slavic mythology desribes how different
cultures influence the development of mythological stories, which can often share similarities.
The thesis also presents several well known animated works and compares them based on their
use of mythology.
In the practical part, the thesis describes the development of the story and the animated film
Rdeča Žoga / Red Ball. The story follows two characters, Nali and Hel, who must face evil. All
stages of the animated film\u27s creation are presented, from pre-production to post-production,
along with the technical challenges encountered during the filmmaking process
The emergence of the (trans)national queer literary subcanons in the post-Yugoslav space
No full text
GRB 221009A
No full textWe present a complete analysis of Fermi Large Area Telescope (LAT) data of GRB 221009A, the brightest gamma-ray burst (GRB) ever detected. The burst emission above 30 MeV detected by the LAT preceded, by 1 s, the low-energy (<10 MeV) pulse that triggered the Fermi Gamma-Ray Burst Monitor (GBM), as has been observed in other GRBs. The prompt phase of GRB 221009A lasted a few hundred seconds. It was so bright that we identify a bad time interval of 64 s caused by the extremely high flux of hard X-rays and soft gamma rays, during which the event reconstruction efficiency was poor and the dead time fraction quite high. The late-time emission decayed as a power law, but the extrapolation of the late-time emission during the first 450 s suggests that the afterglow started during the prompt emission. We also found that high-energy events observed by the LAT are incompatible with synchrotron origin, and, during the prompt emission, are more likely related to an extra component identified as synchrotron self-Compton (SSC). A remarkable 400 GeV photon, detected by the LAT 33 ks after the GBM trigger and directionally consistent with the location of GRB 221009A, is hard to explain as a product of SSC or TeV electromagnetic cascades, and the process responsible for its origin is uncertain. Because of its proximity and energetic nature, GRB 221009A is an extremely rare event
Time evolution of Mg II in SDSS J2320+0024
No full textContext. We present results from our spectroscopic follow-up of SDSS J2320+0024, a candidate binary supermassive black hole (SMBH) with a suspected subparsec separation, identified by a 278-day periodicity observed in its multiband optical light curves. Such systems serve as a crucial link between binaries with long periods (tens of years), which are influenced by tidal forces with minimal gravitational wave damping, and ultra-short-period binaries (≤order of days), which are dominated by gravitational wave-driven inspiral.
Aims. We investigated the dramatic variability in the complex Mg II emission line profile with the aim of testing the alignments of the observed photometric light curves and the spectroscopic signatures in the context of the binary SMBH system.
Methods. We extracted the pure broad Mg II line from newly obtained Gemini and Magellan spectra and measured the emission line parameters to determine the fundamental dynamical parameters of the SMBH’s binary system. We adopted the PoSKI subparsec binary SMBH model, which includes a broad-line region around a less massive component and a circumbinary broad-line region, to interpret the observed variability in the spectral profile.
Results. We find that the Mg II broad-line profile has a distinctive complex shape, with asymmetry and two peaks, which has varied across recent and archival observations. The temporal variability of the Mg II line profile may be associated with emission from the binary SMBH system, whose components have masses M1 = 2 × 107 M⊙ and M2 = 2 × 108 M⊙ and eccentricity e = 0.1. We discuss other plausible physical interpretations. With a total estimated mass of ∼109 M⊙ and a sub-annual orbital period, this system may be a rare example of a high-mass compact SMBH binary candidate and, thus, should be part of further investigations of the evolution of binary systems. This study highlights the synergies between spectroscopic follow-up and future massive time-domain photometric surveys, such as the Vera C. Rubin Observatory Legacy Survey of Space and Time