Search results for "Functional material"
showing 10 items of 11 documents
Section: Advanced Composites and Applications (15th February, 2022, Riga, Latvia) : Book of Abstracts
2022
The section ‘Advanced Composites and Applications’ was organized by the Institute for Mechanics of Materials of the University of Latvia (LU MMI) on 15.02.2022 as a part of the annual 80th scientific conference of the University of Latvia. It was organized remotely in Zoom. The official language of the section was English. The duration of the presentation was 10-15 minutes. The section was devoted to the discussion of the recent results within following topics: structure and properties of polymers and polymer-based composites, long-term properties, creep, and environmental ageing, composites for advanced applications, mechanical aspects of technology, multifunctional properties.
Editorial: Advanced Functional Materials Derived From One-Dimensional Clay Minerals
2021
New Hybrid Organic-inorganic Multifunctional Materials Based on Polydopamine-like Chemistry
2021
Taking inspiration from the chemistry of dopamine, a simple and economic synthetic approach toward the synthesis of a series of silica-based polydopamine-like materials has been developed. Mild conditions and easy manipulation are the strongest aspects of this methodology. Such hybrid materials were successfully used as recyclable catalysts for Knoevenagel reactions.
Structural investigation of crystallized Ge-Ga-Se chalcogenide glasses
2018
H. Klym thanks to the Ministry of Education and Science of Ukraine for support and Dr. P. Demchenko for the assistance in XRD experiments.
Bimetallic PdAg nanoparticle arrays from monolayer films of diblock copolymer micelles
2015
MICROSCOPIE+ATARI+EEH:GMA:TBG:NSP:MAO; International audience; The self-assembly technique provides a highly efficient route to generate well-ordered structures on a nanometer scale. In this paper, well-ordered arrays of PdAg alloy nanoparticles on flat substrates with narrow distributions of particle size (6-7 nm) and interparticle spacing (about 60 nm) were synthesized by the block copolymer micelle approach. A home-made PS-b-P4VP diblock copolymer was prepared to obtain a micellar structure in toluene. Pd and Ag salts were then successfully loaded in the micellar core of the PS-b-P4VP copolymer. A self-assembled monolayer of the loaded micelles was obtained by dipping the flat substrate …
Photochemical behavior in azobenzene having acidic groups. Preparation of magnetic photoresponsive gels
2011
[EN] The photochemistry of three azobenzenes representing contrasting photochemical behaviors is described in the present work. Thus, Methyl Orange (MO, 4-[[(4-dimethylamino)phenyl]-azo]benzenesulfonic acid sodium salt, hereinafter (1) and 4-hydroxyazobenzene-4'-sulfonic acid (2) undergo in water fast photochemical proton shift, with decays in the microsecond timescale. In contrast to the previous cases, azobenzene-4,4'-dicarboxylic acid (3) undergoes photoisomerization in water. This photochemical behavior allows the preparation of aqueous gels with Aerosil as gelating agent (5% weight) exhibiting high cyclability and photoreversible isomerization of the trans to cis (300 nm irradiation) a…
Nitrogen-doped carbon dots embedded in a SiO2 monolith for solid-state fluorescent detection of Cu2+ ions
2017
We describe the simple fabrication of SiO2 sol-gel monoliths embedding highly luminescent carbon nanodots (CDs) sensitive to metal ions. The pristine CDs we synthesize display an intense dual emission consisting in two fluorescence bands in the green and violet region, and we demonstrate that this photoluminescence is substantially unchanged when the dots are incorporated in the SiO2 matrix. The emission of these CDs is quenched by interactions with Cu2+ ions, which can be used to detect these ions with a detection limit of 1 μM. The chromophores remain accessible to diffusing Cu2+ ions even after embedding CDs in the sol-gel monolith, where their detection capabilities are preserved. Such …
X-ray Spectroscopy of (Ba,Sr,La)(Fe,Zn,Y)O3-δIdentifies Structural and Electronic Features Favoring Proton Uptake
2020
Mixed protonic–electronic conducting oxides are key functional materials for protonic ceramic fuel cells. Here, (Ba,Sr,La)(Fe,Zn,Y)O3−δ perovskites are comprehensively investigated by X-ray spectroscopy (in oxidized and reduced states). Extended X-ray absorption fine structure shows that Zn,Y doping strongly increases the tendency for Fe–O–Fe buckling. X-ray absorption near-edge spectroscopy at the Fe K-edge and X-ray Raman scattering at the O K edge demonstrate that both iron and oxygen states are involved when the samples are oxidized, and for the Zn,Y doped materials, the hole transfer from iron to oxygen is less pronounced. This can be correlated with the observation that these material…
Spin state switching in iron coordination compounds
2013
The article deals with coordination compounds of iron(II) that may exhibit thermally induced spin transition, known as spin crossover, depending on the nature of the coordinating ligand sphere. Spin transition in such compounds also occurs under pressure and irradiation with light. The spin states involved have different magnetic and optical properties suitable for their detection and characterization. Spin crossover compounds, though known for more than eight decades, have become most attractive in recent years and are extensively studied by chemists and physicists. The switching properties make such materials potential candidates for practical applications in thermal and pressure sensors …
Advanced Composites and Applications: Book of abstracts
2023
The section ‘Advanced Composites and Applications’ was organized by the Institute for Mechanics of Materials of the University of Latvia (LU MMI) on 16.02.2023 as a part of the annual 81th scientific conference of the University of Latvia. It was organized remotely in Zoom. The official language of the section was English. The duration of the presentation was 10 minutes. The section was devoted to the discussion of the recent results within following topics: structure and properties of polymers and polymer-based composites, long-term properties, creep, and environmental ageing, composites for advanced applications, mechanical aspects of technology, and multifunctional properties.