Light induced coarsening of metal nanoparticles

2019 ◽  
Vol 7 (19) ◽  
pp. 11756-11763 ◽  
Author(s):  
Liuxian Zhang ◽  
Qianlang Liu ◽  
Peter A. Crozier
Keyword(s):  
Metal Nanoparticles ◽  
Metal Particle ◽  
Light Illumination ◽  
Particle Coarsening ◽  
Semiconducting Substrate

Metal particle coarsening driven by light illumination of the supporting semiconducting substrate.

scholarly journals Surface chemistry of quantum-sized metal nanoparticles under light illumination

2021 ◽  
Author(s):  
Shea Stewart ◽  
Qilin Wei ◽  
Yugang Sun
Keyword(s):  
Surface Chemistry ◽  
Metal Nanoparticles ◽  
Metal Surfaces ◽  
Size Reduction ◽  
Light Illumination

Size reduction of metal nanoparticles increases the exposure of metal surfaces significantly, favoring heterogeneous photochemistry at the surface of the nanoparticles.

scholarly journals Влияние металлических наночастиц на распространение предельно коротких оптических импульсов в графене

2019 ◽  
Vol 126 (3) ◽  
pp. 346
Author(s):  
Н.Н. Конобеева ◽  
Д.С. Скворцов ◽  
М.Б. Белоненко
Keyword(s):  
Metal Nanoparticles ◽  
Exchange Interaction ◽  
Metal Particle ◽  
Effective Hamiltonian ◽  
Two Dimensional ◽  
Optical Pulses ◽  
Extremely Short Optical Pulses

AbstractThe propagation of two-dimensional extremely short optical pulses in graphene with metal nanoparticles has been investigated. The effects that are observed when changing the parameters of the effective Hamiltonian, which takes into account the exchange interaction, have been studied. It has been revealed that the introduction of metallic adatoms into graphene leads to an increase in the amplitude of the pulse. This effect can be enhanced by choosing a particular metal particle .

Electron Microscopy of the Shape of Small Metal Particles

1977 ◽  
Vol 35 ◽  
pp. 300-301
Author(s):  
M. Jose Yacaman
Keyword(s):  
Electron Microscopy ◽  
Metal Particle ◽  
Field Experiments ◽  
Size Range ◽  
Dark Field ◽  
Metal Particles ◽  
Bragg Condition ◽  
Crystal Particle ◽  
Small Metal Particle ◽  
Small Metal Particles

In the Study of small metal particles the shape is a very Important parameter. Using electron microscopy Ino and Owaga(l) have studied the shape of twinned particles of gold. In that work electron diffraction and contrast (dark field) experiments were used to produce models of a crystal particle. In this work we report a method which can give direct information about the shape of an small metal particle in the amstrong- size range with high resolution. The diffraction pattern of a sample containing small metal particles contains in general several systematic and non- systematic reflections and a two-beam condition can not be used in practice. However a N-beam condition produces a reduced extinction distance. On the other hand if a beam is out of the bragg condition the effective extinction distance is even more reduced.

Low-light-level three-dimensional video microscope with long working distance objective lenses

1994 ◽  
Vol 52 ◽  
pp. 226-227
Author(s):  
W. Lin ◽  
J. Gregorio ◽  
T.J. Holmes ◽  
D. H. Szarowski ◽  
J.N. Turner
Keyword(s):  
Three Dimensional ◽  
Light Level ◽  
Stereo Pair ◽  
Light Illumination ◽  
Initial Image ◽  
Low Light ◽  
Image Recording ◽  
Depth Discrimination ◽  
Video Microscope ◽  
Working Distance

A low-light level video microscope with long working distance objective lenses has been built as part of our integrated three-dimensional (3-D) light microscopy workstation (Fig. 1). It allows the observation of living specimens under sufficiently low light illumination that no significant photobleaching or alternation of specimen physiology is produced. The improved image quality, depth discrimination and 3-D reconstruction provides a versatile intermediate resolution system that replaces the commonly used dissection microscope for initial image recording and positioning of microelectrodes for neurobiology. A 3-D image is displayed on-line to guide the execution of complex experiments. An image composed of 40 optical sections requires 7 minutes to process and display a stereo pair.The low-light level video microscope utilizes long working distance objective lenses from Mitutoyo (10X, 0.28NA, 37 mm working distance; 20X, 0.42NA, 20 mm working distance; 50X, 0.42NA, 20 mm working distance). They provide enough working distance to allow the placement of microelectrodes in the specimen.

Fabrication of Nanocomposite Scaffolds Including Metal Nanoparticles for Tissue Engineering Applications

2017 ◽  
Vol 4 (1) ◽  
pp. 23-30
Author(s):  
Melek Taygun ◽  
◽  
Çağkan Alemdar ◽  
Emre Ekmen ◽  
İrem Keskin ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Metal Nanoparticles ◽  
Engineering Applications ◽  
Nanocomposite Scaffolds

Effect of Illumination on Organic Polymer Thin-Film Transistors

2003 ◽  
Vol 771 ◽  
Author(s):  
Michael C. Hamilton ◽  
Sandrine Martin ◽  
Jerzy Kanicki
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Drain Current ◽  
Charge Carriers ◽  
Electrical Performance ◽  
Organic Polymer ◽  
Light Illumination ◽  
Polymer Thin Film ◽  
Channel Region ◽  
White Light Illumination

AbstractWe have investigated the effects of white-light illumination on the electrical performance of organic polymer thin-film transistors (OP-TFTs). The OFF-state drain current is significantly increased, while the drain current in the strong accumulation regime is relatively unaffected. At the same time, the threshold voltage is decreased and the subthreshold slope is increased, while the field-effect mobility of the charge carriers is not affected. The observed effects are explained in terms of the photogeneration of free charge carriers in the channel region due to the absorbed photons.

Natural Killer Cell Inspired AIE Nanoterminator for Blood-Brain-Barrier Crossing via Tight-Junction Modulation and NIR-II Gliomas Theranostics

2020 ◽  
Author(s):  
Guanjun Deng ◽  
Xinghua Peng ◽  
Zhihong Sun ◽  
Wei Zheng ◽  
Jia Yu ◽  
...  
Keyword(s):  
Natural Killer Cell ◽  
Natural Killer ◽  
Intracellular Signaling ◽  
Soft Matter ◽  
Tumor Imaging ◽  
Nk Cell ◽  
Killer Cell ◽  
Light Illumination ◽  
Blood Brain ◽  
Intracellular Signaling Cascade

Nature has always inspired robotic designs and concepts. It is conceivable that biomimic nanorobots will soon play a prominent role in medicine. In this paper, we developed a natural killer cell-mimic AIE nanoterminator (NK@AIEdots) by coating natural kill cell membrane on the AIE-active polymeric endoskeleton, PBPTV, a highly bright NIR-II AIE-active conjugated polymer. Owning to the AIE and soft-matter characteristics of PBPTV, as-prepared nanoterminator maintained the superior NIR-II brightness (quantum yield ~8%) and good biocompatibility. Besides, they could serve as tight junctions (TJs) modulator to trigger an intracellular signaling cascade, causing TJs disruption and actin cytoskeleton reorganization to form intercellular “green channel” to help themselves crossing Blood-Brain Barriers (BBB) silently. Furthermore, they could initiatively accumulate to glioblastoma cells in the complex brain matrix for high-contrast and through-skull tumor imaging. The tumor growth was also greatly inhibited by these nanoterminator under the NIR light illumination. As far as we known, The QY of PBPTV is the highest among the existing NIR-II luminescent conjugated polymers. Besides, the NK-cell biomimetic nanorobots will open new avenue for BBB-crossing delivery.

Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

2018 ◽  
Author(s):  
Elaine A. Kelly ◽  
Judith E. Houston ◽  
Rachel Evans
Keyword(s):  
Real Time ◽  
Absorption Spectroscopy ◽  
Self Assembly ◽  
Uv Light ◽  
Wormlike Micelles ◽  
Tetraethylene Glycol ◽  
Light Illumination ◽  
First Time ◽  
Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such as<i></i>drug delivery and micellar catalysis. Currently, their behaviour in the equilibrium <i>cis-</i>and <i>trans</i>-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>) using small-angle neutron scattering (SANS). We show that the incorporation of <i>in-situ</i>UV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>could switch between wormlike micelles (<i>trans</i>native state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked <i>in</i><i>-situ</i>through combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

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