1. Insight into the interdependence of Ni and Al in bifunctional Ni/ZSM-5 catalysts at the nanoscaleHue-Tong Vu, Iztok Arčon, Danilo Oliveira de Souza, Simone Pollastri, Goran Dražić, Janez Volavšek, Gregor Mali, Nataša Zabukovec Logar, Nataša Novak Tušar, 2022, izvirni znanstveni članek Opis: Catalyst design is crucial for improving catalytic activity and product selectivity. In a bifunctional Ni/ZSM-5
zeolite type catalyst, catalytic properties are usually tuned via varying Al and Ni contents. While changes in
acid properties associated with Al sites are usually closely investigated, Ni phases, however, receive
inadequate attention. Herein, we present a systematic structural study of Ni in the Ni/ZSM-5 materials by
using Ni K-edge XANES and EXAFS analyses, complemented by XRD and TEM, to resolve the changes in
the local environment of Ni species induced by the different Al contents of the parent ZSM-5 prepared
by a “green”, template free technique. Ni species in Ni/ZSM-5 exist as NiO crystals (3–50 nm) and as
charge compensating Ni2+ cations. The Ni K-edge XANES and EXAFS results enabled the quantification
of Ni-containing species. At a low Al to Si ratio (nAl/nSi # 0.04), the NiO nanoparticles predominate in
the samples and account for over 65% of Ni phases. However, NiO is outnumbered by Ni2+ cations
attached to the zeolite framework in ZSM-5 with a high Al to Si ratio (nAl/nSi ¼ 0.05) due to a higher
number of framework negative charges imparted by Al. The obtained results show that the number of
highly reducible and active NiO crystals is strongly correlated with the framework Al sites present in
ZSM-5 zeolites, which depend greatly on the synthesis conditions. Therefore, this kind of study is
beneficial for any further investigation of the catalytic activities of Ni/ZSM-5 and other metal-modified
bifunctional catalysts.
Ključne besede: Ni/ZSM-5 catalysts, zeolite, Ni XANES, EXAFS
Objavljeno v RUNG: 11.05.2022; Ogledov: 2935; Prenosov: 52
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2. Stimulation of acidic reduction of nitrite to nitric oxide by soybean phenolics: possible relevance to gastrointestinal host defensePablo Ferreira, Maria Souza, Robert Alvin Bernedo Navarro, Rogério Conceição, Edlaine Linhares, Tomomasa Yano, Ione Salgado, 2011, izvirni znanstveni članek Ključne besede: Soybean, nitric oxide, host defense
Objavljeno v RUNG: 27.05.2019; Ogledov: 4080; Prenosov: 0
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3. Testing the agreement between the Xmax distributions measured by the Pierre Auger and Telescope Array ObservatoriesV. De Souza, Andrej Filipčič, Gašper Kukec Mezek, Ahmed Saleh, Samo Stanič, Marta Trini, Darko Veberič, Serguei Vorobiov, Lili Yang, Danilo Zavrtanik, Marko Zavrtanik, 2017, objavljeni znanstveni prispevek na konferenci Ključne besede: Xmax distributions, Pierre Auger Observatory, Telescope Array
Objavljeno v RUNG: 19.02.2018; Ogledov: 4801; Prenosov: 182
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4. Measurement of the energy spectrum of cosmic rays with the Pierre Auger ObservatoryVitor de Souza, Andrej Filipčič, Ahmed Saleh, Samo Stanič, Darko Veberič, Serguei Vorobiov, Danilo Zavrtanik, Marko Zavrtanik, 2016, objavljeni znanstveni prispevek na konferenci Ključne besede: Ultra-high energy cosmic rays (UHECR), UHECR elemental composition, Pierre Auger Observatory, extensive air showers (EAS), EAS longitudinal profiles, depth of shower maximum
Objavljeno v RUNG: 09.11.2016; Ogledov: 5648; Prenosov: 0
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5. An update on the measurements of the depth of shower maximum made at the Pierre Auger ObservatoryVitor de Souza, Andrej Filipčič, Thomas Paul, Samo Stanič, Darko Veberič, Danilo Zavrtanik, Marko Zavrtanik, 2013, objavljeni znanstveni prispevek na konferenci Ključne besede: Observatorij Pierre Auger, kozmični žarki, masna sestava
Objavljeno v RUNG: 15.10.2013; Ogledov: 6184; Prenosov: 31
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6. Results from the Pierre Auger ObservatoryVitor de Souza, Alexandre Creusot, Andrej Filipčič, Thomas Paul, Darko Veberič, Danilo Zavrtanik, Marko Zavrtanik, 2010, objavljeni znanstveni prispevek na konferenci Ključne besede: kozmični žarki, hadronski modeli interakcij, Observatorij Pierre Auger
Objavljeno v RUNG: 15.10.2013; Ogledov: 6769; Prenosov: 27
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