61. Nanobody Engineering Provides Diagnostic Reagents For The Quantification Of The Toxic Microalgae Alexandrium minutumRobert Alvin Bernedo-Navarro, Sandra Oloketuyi, Giulio Bernardinelli, Eda Mehmeti, Kurt Kalcher, Ario De Marco, 2019, published scientific conference contribution abstract Keywords: Nanobodies, DNAzyme, electrochemical impedance spectroscopy, toxic microalgae
Published in RUNG: 09.09.2019; Views: 3542; Downloads: 0
This document has many files! More... |
62. Au and Ag on the Bi2Se3(0001) Surface: Experimental Electronic and Physical PropertiesSandra Gardonio, Mattia Fanetti, Katja Ferfolja, Matjaž Valant, published scientific conference contribution abstract Abstract: Binary bismuth chalcogenides, Bi2Se3 and Bi2Te3, have been extensively studied as reference topological
insulators (TIs). These materials are bulk insulators with topological surface states (TSS) crossing the
Fermi level. In contrast to conventional surface states of metals, the TSS are extremely robust
against local modifications at the surface, such as adsorbed adatoms, localized defects or changes in the surface termination. This aspect makes the TIs attractive for applications in spintronics, plasmonics, quantum computing and catalysis.
A theoretical model of charge transport by the TI surface states predicts that the TSS survive, provided that bonding at the metal/TI interface is weak. Ab-initio calculations have been done to understand the electronic properties of Au, Ni, Pt, Pd and graphene layers in a contact with Bi2Se3. These calculations showed that for Au and graphene the spin-momentum locking of TSS is maintained at the interface. In another theoretical study, Ag and Au thin layers on Bi2Se3 have been predicted to show a large Rashba splitting and a high spin polarization of the Ag quantum wells, providing a great potential for development of the spintronic devices. Finally, the calculations have foreseen that the presence of the robust TSS affects the adsorption properties of metals (Au bi-layer and clusters of Au, Ag, Cu, Pt, and Pd) supported on TI, in some cases resulting in the enhancement of the catalytic processes.
Despite the fundamental importance of the metal/TI interfaces and a number of theoretical studies
predicting exotic interfacial phenomena, the experimental knowledge about the metals on the TI surfaces is surprisingly limited, especially concerning combined study of morphology, growth mode, electronic and chemical properties.
In order to exploit the predicted physical properties of such systems, it is especially important to extend the study above the diluted coverage regime and to understand what is the growth morphology of the metal on the TI surface, to what extent the metal overlayer interacts with the TI substrate, how the TSS change with the presence of the metal overlayer and what is the reactivity of the system at the different stages of the overlayer growth.
Within this frame, we present a comprehensive surface sensitive study, of Au and Ag on Bi2Se3 by means of ARPES, XPS, SEM, LEED and XRD. The obtained results allow us to discuss the relation between electronic and physical properties at two of the most important model metal/TI interfaces
Keywords: topological insulator, electronic properties, synchrotron radiation
Published in RUNG: 27.06.2019; Views: 3330; Downloads: 0
This document has many files! More... |
63. |
64. Growth, morphology and stability of Au in contact with the Bi[sub]2Se[sub]3(0 0 0 1) surfaceMattia Fanetti, Iuliia Mikulska, Katja Ferfolja, Paolo Moras, Polina M. Sheverdyaeva, M. Panighel, A. Lodi-Rizzini, I. Píš, S. Nappini, Matjaž Valant, Sandra Gardonio, 2018, original scientific article Keywords: metal contact, topological insulator contact, growth mode, electronic properties, chemical properties, photoemission spectroscopy, microscopy
Published in RUNG: 05.12.2018; Views: 3672; Downloads: 0
This document has many files! More... |
65. |
66. |
67. Atomic-level mechanisms of magnesium oxidationSandra Gardonio, Mattia Fanetti, Matjaž Valant, Dmytro Orlov, 2016, published scientific conference contribution Abstract: Magnesium has been recently becoming an increasingly popular material for various applications. However, excessive chemical reactivity, and oxidation rate in particular, is a major obstruction on the way of Mg to become widely adopted. A significant problem causing the lack of Mg reactivity control is insufficient understanding of mechanisms involved in the oxidation of magnesium surface. Herewith we present the investigation of atomic-level mechanisms of oxidation initiation and propagation in pure Mg. Namely, X-ray photoelectron spectroscopy at synchrotron Elettra was used as a surface sensitive direct method to determine the valence of Mg and O and the valence band states at the early stage of oxide formation over a principal, most densely packed, crystallographic plane (0001) in pure Mg. The mechanisms of oxygen adsorption on magnesium free surface followed by oxidation (i.e. initiation and kinetics of MgO formation) are clarified. Copyright © 2016 by The Minerals, Metals & Materials Society. All rights reserved.
Keywords: Magnesium, Oxidation, Synchrotron radiation, X-ray photoelectron spectroscopy
Published in RUNG: 25.08.2017; Views: 5071; Downloads: 0
This document has many files! More... |
68. |
69. Pursuing the stabilisation of crystalline nanostructured magnetic manganites through a green low temperature hydrothermal synthesisArianna Minelli, Paolo Dolcet, Stefano Diodati, Sandra Gardonio, Claudia Innocenti, Denis Badocco, Stefano Gialanella, Paolo Pastore, Luciano Pandolfo, Andrea Caneschi, Angela Trapanati, Silvia Gross, 2017, original scientific article Abstract: A quick, easy and green water-based synthesis protocol involving coprecipitation of oxalates combined with hydrothermal treatment resulted in the crystallisation of nanostructured manganites at a relatively low temperature (180 °C). The subcritical hydrothermal approach was shown to play a key role in stabilising phases which are generally achieved at much higher temperatures and under harsher conditions, thus disclosing an exciting alternative for their synthesis. Through this mild wet chemistry approach, the compounds CuMnO2, ZnMn2O4 and ZnMnO3 were synthesised as nanocrystalline powders. Noticeably, the optimised route proved to be effective in stabilising the exotic polymorph cubic spinel ZnMnO3 in pure form. This is particularly notable, as very few records concerning this compound are available in the literature. The compounds were fully characterised from compositional, structural, morphological and magnetic points of view.
Keywords: nanostructured manganites, low temperature wet chemistry synthesis
Published in RUNG: 28.03.2017; Views: 4324; Downloads: 0
This document has many files! More... |
70. Učinki herbicida glifosata v čisti obliki in v pripravku na deževnike (Eisenia andrei)Sandra Dukić, 2016, undergraduate thesis Abstract: Zaradi naraščanja svetovnega prebivalstva prihaja do vse večjih potreb po pridelavi hrane, posledično pa so tla izpostavljena vse večjim pritiskom izrabe ter različnim onesnaževalom, med katerimi prevladujejo pesticidi. Najbolj razširjen razred pesticidov v kmetijstvu so herbicidi, od katerih je najpogosteje uporabljen glifosat. Ker imajo pesticidi mnogokrat učinke na netarčne organizme, se zanje izvajajo ocene tveganj. Učinke na organizme se preverja s standardiziranimi ekotoksikološkimi testi. V okviru sledečega diplomskega dela se je raziskovalo oziroma primerjalo učinke dveh različnih oblik glifosata na deževnike vrste Eisenia andrei, Bouché, 1972. Uporabljen je bil glifosat v pripravku ter glifosat v obliki čiste aktivne učinkovine. Po podatkih iz literature naj bi bili pripravki zaradi vsebnosti pomožnih sredstev za talne organizme bolj strupeni. Pri ugotavljanju vpliva na rast deževnikov je prišlo do ugotovitve, da je glifosat v pripravku res bistveno bolj vplival na spremembo mas živali, saj so se v mnogih primerih znižale. Medtem so se pri čistem glifosatu povečale pri vseh uporabljenih koncentracijah pesticida. Na umrljivost v obeh primerih ni bilo vpliva, saj so preživele vse živali. Pri ugotavljanju vpliva na razmnoževanje je bil test s čistim glifosatom po kriterijih OECD neveljaven, zato ni bilo mogoče primerjati rezultatov. Vseeno je iz vseh dobljenih rezultatov mogoče sklepati, da glifosat za deževnike ni zelo strupen.
Keywords: Glifosat, pesticidi, deževniki, Eisenia andrei, strupenost, ekotoksikologija
Published in RUNG: 15.09.2016; Views: 6524; Downloads: 327
 Full text (1,35 MB) |
