Laser-driven structural transformations in dextran-graft-PNIPAM copolymer/Au nanoparticles hybrid nanosystem: the role of plasmon heating and attractive optical forces

Structural transformations in D-g-PNIPAM/AuNPs hybrid nanosystem arise from the synergetic action of plasmonic heating and attractive optical plasmonic forces.

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Laser-Driven Aggregation in Dextran–Graft–PNIPAM/Silver Nanoparticles Hybrid Nanosystem: Plasmonic Effects

Ukrainian Journal of Physics ◽

10.15407/ujpe65.3.254 ◽

2020 ◽

Vol 65 (3) ◽

pp. 254

Author(s):

O. A. Yeshchenko ◽

A. O. Bartenev ◽

A. P. Naumenko ◽

N. V. Kutsevol ◽

Iu. I. Harahuts ◽

...

Keyword(s):

Silver Nanoparticles ◽

Ag Nanoparticles ◽

Laser Wavelength ◽

Solution Temperature ◽

Optical Forces ◽

Ag Nps ◽

Induced Aggregation ◽

Conformation Transition ◽

Hybrid Nanosystem

The laser-induced aggregation in the thermosensitive dextran grafted-poly(N-isopropylacrylamide) copolymer/Ag nanoparticles (D–g–PNIPAM/AgNPs) hybrid nanosystem in water has been observed. The laser-induced plasmonic heating of Ag NPs causes the Lower Critical Solution Temperature (LCST) conformation transition in D–g–PNIPAM/AgNPs macromolecules which shrink during the transition. The shrinking decreases sharply the distance between the silver nanoparticles that launches the aggregation of Ag NPs and the appearance of plasmonic attractive optical forces acting between the nanoparticles. It has been shown that the approach of the laser wavelength to the surface plasmon resonance in Ag nanoparticles leads to a significant strengthening of the observed aggregation, which proves its plasmon nature. The laser-induced transformations in the D–g–PNIPAM/AgNPs nanosystem have been found to be essentially irreversible that differs principally them from the temperature-induced transformations. Such fundamental difference proves the crucial role of the optical forces arising due to the excitation of surface plasmons in Ag NPs.

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Mineral transformations

Mineralogical Magazine ◽

10.1180/002646100549157 ◽

2000 ◽

Vol 64 (2) ◽

pp. 155-156 ◽

Cited By ~ 1

Author(s):

S. A. T. Redfern

Keyword(s):

European Union ◽

Chemical Composition ◽

Structural Transformations ◽

Atomic Scale ◽

Special Session ◽

The European Union ◽

Mineral Science ◽

Research Programmes ◽

Mineral Transformations

One of the major goals of mineral science is attaining an understanding of the atomic-scale mechanisms and dynamics of minerals that control their structural transformations as a function of pressure, temperature or chemical composition in the natural environment. Examples of research programmes that sail under this heading include those devoted to observing and modelling the role of phase transformations on controlling mineral microstructures, ordering, elasticity, transport, premelting and exsolution. The geological relevance and intrinsic importance (as being representative of specific properties or thermodynamic/ kinetic behaviour) of mineral transformations has long been appreciated. It prompted the recent initiation of a network on Mineral Transformations (http://www.esc.cam.ac.uk/mintrans/) under the European Union TMR Programme. In response to this development, a special session on Mineral Transformations was held at the EUG congress in Strasbourg last year.

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The role of oxygen packing in the structural transformations of oxide glasses

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s205327331609776x ◽

2016 ◽

Vol 72 (a1) ◽

pp. s150-s150

Author(s):

Anita Zeidler ◽

Philip S. Salmon

Keyword(s):

Structural Transformations ◽

Oxide Glasses

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Facet-dependent activity of shape-controlled TiO2 supported Au nanoparticles for water-gas shift reaction†

Catalysis Science & Technology ◽

10.1039/d1cy01823j ◽

2022 ◽

Author(s):

Yuanting Tang ◽

Yongjie Chen ◽

Xiao Liu ◽

Chengxiong Wang ◽

Yunkun Zhao ◽

...

Keyword(s):

Au Nanoparticles ◽

Water Gas Shift ◽

Water Gas Shift Reaction ◽

Oxide Interface ◽

Wgs Reaction ◽

Dependent Activity ◽

Shape Controlled ◽

Shift Reaction ◽

Water Gas

The bifunctional role of noble metal/oxide interface in the activation of reactants is of vital importance in heterogeneous catalysis of water-gas shift (WGS) reaction. Herein, three types of shape-controlled TiO2...

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Phonons in deformable microporous crystalline solids

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1515/zkri-2018-2152 ◽

2019 ◽

Vol 234 (7-8) ◽

pp. 513-527 ◽

Cited By ~ 1

Author(s):

Bogdan Kuchta ◽

Filip Formalik ◽

Justyna Rogacka ◽

Alexander V. Neimark ◽

Lucyna Firlej

Keyword(s):

Periodic Structures ◽

Structural Transformations ◽

Crystalline Solids ◽

Predictive Tool ◽

Crystalline Materials ◽

Numerical Tools ◽

Collective Vibrations ◽

First Time

Abstract Phonons are quantum elastic excitations of crystalline solids. Classically, they correspond to the collective vibrations of atoms in ordered periodic structures. They determine the thermodynamic properties of solids and their stability in the case of structural transformations. Here we review for the first time the existing examples of the phonon analysis of adsorption-induced transformations occurring in microporous crystalline materials. We discuss the role of phonons in determining the mechanism of the deformations. We point out that phonon-based methodology may be used as a predictive tool in characterization of flexible microporous structures; therefore, relevant numerical tools must be developed.

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Plasmonic heating assisted deposition of bare Au nanoparticles on titania nanoshells

Journal of Colloid and Interface Science ◽

10.1016/j.jcis.2010.07.079 ◽

2010 ◽

Vol 351 (2) ◽

pp. 576-579 ◽

Cited By ~ 25

Author(s):

Ivano Alessandri

Keyword(s):

Au Nanoparticles ◽

Plasmonic Heating

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Structural Transformations Versus Hard Particles Motion in the Brass Ingots

Archives of Metallurgy and Materials ◽

10.1515/amm-2017-0362 ◽

2017 ◽

Vol 62 (4) ◽

pp. 2461-2467 ◽

Cited By ~ 3

Author(s):

W. Wołczyński ◽

A.A. Ivanova ◽

P. Kwapisiński ◽

E. Olejnik

Keyword(s):

Continuous Casting ◽

Thermal Gradient ◽

Structural Transformations ◽

Gradient Field ◽

Hard Particles ◽

Columnar Grains ◽

Solid Liquid ◽

Equiaxed Grains ◽

Structural Zones

AbstractA mathematical method for the forecast of the type of structure in the steel static ingot has been recently developed. Currently, the method has been applied to structural zones prediction in the brass ingots obtained by the continuous casting. Both the temperature field and thermal gradient field have been calculated in order to predict mathematically the existence of some structural zones in the solidifying brass ingot. Particularly, the velocity of theliquidusisotherm movement and thermal gradient behavior versus solidification time have been considered. The analysis of the mentioned velocity allows the conclusion that the brass ingots can evince: chilled columnar grains-, (CC), fine columnar grains-, (FC), columnar grains-, (C), equiaxed grains zone, (E), and even the single crystal, (SC), situated axially. The role of the mentioned morphologies is analyzed to decide whether the hard particles existing in the brass ingots can be swallowed or rejected by the solid / liquid (s/l) interface of a given type of the growing grains. It is suggested that the columnar grains push the hard particles to the end of a brass ingot during its continuous casting.

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