A proposal for wide range wavelength switching process using optical force

Physica Scripta ◽

10.1088/1402-4896/ac3fd3 ◽

2021 ◽

Author(s):

Ali Taghizad Fanid ◽

Ali Rostami

Keyword(s):

Optical Waveguides ◽

Optical Force ◽

Core Shell ◽

Shell Nanoparticles ◽

Silica Substrate ◽

Light Coupling ◽

Scattering Effects ◽

Wide Range ◽

Control Light ◽

Core Shell Nanoparticles

Abstract Optomechanical wavelength up-conversion based on optical force and core-shell scattering effects are used to control light coupling between two waveguides. This system consists of two parallel optical waveguides with 20 µm lengths suspended on a silica substrate embedded with Ag/Si/SiO2 core-shell nanoparticles. By mid-IR plane wave illumination with different intensities and different wavelengths on nanoparticles, scattering would increase and result in an improvement in attractive gradient optical force exerted on waveguides. Via bending waveguides toward each other, visible light propagating in the first waveguide would couple to another. PDMS as a polymer is used to reduce the required power for bending waveguides. Results reveal that when waveguides’ gap equilibrium is 400 nm and wavelengths of control and probe lights are 4.5 µm and 0.45 µm respectively, about 10.75 mW/µm2 power is needed to bend waveguides for total coupling of light between waveguides. The efficiency of the coupled waveguides system is %43.

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Synthesis and Advanced Characterization of Polymer-Protein Core-Shell Nanoparticles

Catalysts ◽

10.3390/catal11060730 ◽

2021 ◽

Vol 11 (6) ◽

pp. 730

Author(s):

Erik Sarnello ◽

Tao Li

Keyword(s):

Particle Size ◽

Small Angle ◽

Core Shell ◽

Assembly Process ◽

Shell Nanoparticles ◽

X Ray ◽

X Ray Scattering ◽

Wide Range ◽

Core Shell Nanoparticles ◽

Ray Scattering

Enzyme immobilization techniques are widely researched due to their wide range of applications. Polymer–protein core–shell nanoparticles (CSNPs) have emerged as a promising technique for enzyme/protein immobilization via a self-assembly process. Based on the desired application, different sizes and distribution of the polymer–protein CSNPs may be required. This work systematically studies the assembly process of poly(4-vinyl pyridine) and bovine serum albumin CSNPs. Average particle size was controlled by varying the concentrations of each reagent. Particle size and size distributions were monitored by dynamic light scattering, ultra-small-angle X-ray scattering, small-angle X-ray scattering and transmission electron microscopy. Results showed a wide range of CSNPs could be assembled ranging from an average radius as small as 52.3 nm, to particles above 1 µm by adjusting reagent concentrations. In situ X-ray scattering techniques monitored particle assembly as a function of time showing the initial particle growth followed by a decrease in particle size as they reach equilibrium. The results outline a general strategy that can be applied to other CSNP systems to better control particle size and distribution for various applications.

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Controlled Synthesis and Characterization of Co-Au Core-shell Nanoparticles

MRS Proceedings ◽

10.1557/proc-877-s3.4 ◽

2005 ◽

Vol 877 ◽

Author(s):

Yuping Bao ◽

Hector Calderon ◽

Kannan M. Krishnan

Keyword(s):

Core Shell ◽

Gold Compound ◽

Contrast Imaging ◽

Shell Nanoparticles ◽

Transmission Electron ◽

Wide Range ◽

High Resolution Tem ◽

Core Shell Nanoparticles ◽

Z Contrast ◽

First Time

AbstractCo-Au Core-shell nanoparticles are synthesized by slowly reducing an organo-gold compound on pre-made cobalt seeds with a weak reducer at mild condition. For the first time, these coreshell nanoparticles are generated in non-polar solvent in a controlled manner. The formation theory of core-shell structure, especially the seed size effect, is addressed as well. These coreshell structures are confirmed with a wide range of transmission electron microscopy (TEM) methods, which includes routine TEM images, high resolution TEM, and z-contrast imaging.

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Bubble nucleation and migration in a lead–iron hydr(oxide) core–shell nanoparticle

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1510342112 ◽

2015 ◽

Vol 112 (42) ◽

pp. 12928-12932 ◽

Cited By ~ 10

Author(s):

Kaiyang Niu ◽

Timofey Frolov ◽

Huolin L. Xin ◽

Junling Wang ◽

Mark Asta ◽

...

Keyword(s):

Iron Hydroxide ◽

Steel Corrosion ◽

Elastic Interaction ◽

Bubble Nucleation ◽

Core Shell ◽

In Situ Observation ◽

Shell Nanoparticles ◽

Wide Range ◽

And Migration ◽

Core Shell Nanoparticles

Iron hydroxide is found in a wide range of contexts ranging from biominerals to steel corrosion, and it can transform to anhydrous oxide via releasing O2 gas and H2O. However, it is not well understood how gases transport through a crystal lattice. Here, we present in situ observation of the nucleation and migration of gas bubbles in iron (hydr)oxide using transmission electron microscopy. We create Pb–FeOOH model core–shell nanoparticles in a liquid cell. Under electron irradiation, iron hydroxide transforms to iron oxide, during which bubbles are generated, and they migrate through the shell to the nanoparticle surface. Geometric phase analysis of the shell lattice shows an inhomogeneous stain field at the bubbles. Our modeling suggests that the elastic interaction between the core and the bubble provides a driving force for bubble migration.

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Facile synthesis of high-performance SiO2@Au core–shell nanoparticles with high SERS activity

RSC Advances ◽

10.1039/c8ra05213a ◽

2018 ◽

Vol 8 (54) ◽

pp. 30825-30831 ◽

Cited By ~ 4

Author(s):

Keli Wang ◽

Yanping Wang ◽

Chongwen Wang ◽

Xiaofei Jia ◽

Jia Li ◽

...

Keyword(s):

High Performance ◽

Core Shell ◽

Facile Synthesis ◽

Shell Nanoparticles ◽

Wide Range ◽

Core Shell Nanoparticles ◽

General Method

This study proposes a facile and general method for fabricating a wide range of high-performance SiO2@Au core–shell nanoparticles (NPs).

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Guanidine functionalized core–shell structured magnetic cobalt-ferrite: an efficient nanocatalyst for sonochemical synthesis of spirooxindoles in water

RSC Advances ◽

10.1039/d1ra00967b ◽

2021 ◽

Vol 11 (25) ◽

pp. 15360-15368

Author(s):

Mahla Dadaei ◽

Hossein Naeimi

Keyword(s):

Cobalt Ferrite ◽

Core Shell ◽

Shell Material ◽

Sonochemical Synthesis ◽

Shell Nanoparticles ◽

The Core ◽

Wide Range ◽

Core Shell Nanoparticles

The core/shell nanoparticles have a wide range of applications in the science of chemistry and biomedical. The core-shell material can be different and modified by changing the ingredients or the ratio of core to the shell.

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