scholarly journals Simple, green, ultrasound-assisted preparation of novel core–shell microcapsules from octyl methoxycinnamate and oligomeric proanthocyanidins for UV-stable sunscreen

RSC Advances ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 6374-6382
Author(s):  
Jie Song ◽  
Siqi Chen ◽  
Xu Zhao ◽  
Junbo Cheng ◽  
Yanli Ma ◽  
...  
Keyword(s):  
Inner Core ◽  
Outer Shell ◽  
Core Shell ◽  
Uv Resistance ◽  
Oligomeric Proanthocyanidins ◽  
Ultraviolet Absorbers ◽  
Ultrasound Assisted

With oligomeric proanthocyanidins (OPCs) as the outer shell and ultraviolet absorbers (OMC) as the inner core, OMC/OPCs composite microcapsules were prepared and characterized, and their UV resistance was studied.

Hybrid cured thiol-ene/epoxy networks for core-shell semiconductor packaging

MRS Advances ◽  
2016 ◽  
Vol 1 (1) ◽  
pp. 57-62
Author(s):  
Kayla V. Maaraoui ◽  
Gregory Ellson ◽  
Walter Voit
Keyword(s):  
Shell Thickness ◽  
Outer Shell ◽  
Core Shell ◽  
Glassy Material ◽  
Reaction Conditions ◽  
Optimal Processing ◽  
Diffusion Limited ◽  
Cure Time ◽  
Cure Temperature ◽  
Semiconductor Packaging

ABSTRACTThis research describes thiol-ene/epoxy hybrid networks for core-shell encapsulation of semiconductor devices. A thiol-ene network was formed using ultraviolet-induced radical polymerization, with unreacted thiols and epoxide monomers remaining in the network. Immersion in tributylamine catalyzed the thiol-epoxy coupling to produce a diffusion-limited hard outer shell. Tensile testing shows that the initial thiol-ene product (core) has elastomeric behavior, while the secondary curing creates a glassy material (shell) at room temperature due to thiol-epoxy coupling. Bulk samples of the material form a hard outer shell surrounding a soft core depending on the secondary cure conditions. There are positive relationships between wall thickness and secondary cure temperature and cure time, enabling control of shell thickness by varying reaction conditions. Shell thicknesses were measured up to 1.8 mm when immersed in tributylamine for up to 150 minutes and up to 140 °C. The ability to control core-shell thickness of dual-cured networks is applicable in device encapsulation processes. Core-shell encapsulants for microelectronics may provide further shock and impact protection for durable electronic devices. Further aging and operational studies will be needed to determine time-stability and optimal processing of the core-shell structure.

scholarly journals An Investigation into the Bulk and Surface Phase Transformations of Bimetallic Pd-In/Al2O3 Catalyst during Reductive and Oxidative Treatments In Situ

Catalysts ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 859
Author(s):  
Nadezhda S. Smirnova ◽  
Evgeny V. Khramov ◽  
Galina N. Baeva ◽  
Pavel V. Markov ◽  
Andrey V. Bukhtiyarov ◽  
...  
Keyword(s):  
Inner Core ◽  
Core Shell ◽  
Surface Phase ◽  
The Core ◽  
Metallic Palladium ◽  
Different Temperatures ◽  
Core Shell Structure ◽  
Al2o3 Catalyst ◽  
Intermetallic Nanoparticles

A series of oxidative treatments of PdIn-supported intermetallic nanoparticles at different temperatures were performed. The bulk and surface structure of catalyst during phase transformation was investigated by bulk- and surface-sensitive techniques (in situ XAFS, DRIFTS of adsorbed CO). It was found that comparison of palladium and indium fractions in bulk and on the surface suggests the formation of a «core-shell» structure. According to obtained results, the core consists of In-depleted intermetallic compound or inhomogeneous bimetallic phase with the inner core of metallic Pd, when a mixture of indium oxide, metallic palladium and small part of PdIn is present on the surface.

scholarly journals Nanoscale Mapping of Heterogeneous Strain and Defects in Individual Magnetic Nanocrystals

Crystals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 658
Author(s):  
Xiaowen Shi ◽  
Ross Harder ◽  
Zhen Liu ◽  
Oleg Shpyrko ◽  
Eric Fullerton ◽  
...  
Keyword(s):  
Uniform Distribution ◽  
Displacement Field ◽  
Density Functional ◽  
Core Region ◽  
Outer Shell ◽  
Core Shell ◽  
Diffractive Imaging ◽  
The Core ◽  
Partial Dislocations ◽  
Distribution Of Magnetization

We map the three-dimensional strain heterogeneity within a single core-shell Ni nanoparticle using Bragg coherent diffractive imaging. We report the direct observation of both uniform displacements and strain within the crystalline core Ni region. We identify non-uniform displacements and dislocation morphologies across the core–shell interface, and within the outer shell at the nanoscale. By tracking individual dislocation lines in the outer shell region, and comparing the relative orientation between the Burgers vector and dislocation lines, we identify full and partial dislocations. The full dislocations are consistent with elasticity theory in the vicinity of a dislocation while the partial dislocations deviate from this theory. We utilize atomistic computations and Landau–Lifshitz–Gilbert simulation and density functional theory to confirm the equilibrium shape of the particle and the nature of the (111) displacement field obtained from Bragg coherent diffraction imaging (BCDI) experiments. This displacement field distribution within the core-region of the Ni nanoparticle provides a uniform distribution of magnetization in the core region. We observe that the absence of dislocations within the core-regions correlates with a uniform distribution of magnetization projections. Our findings suggest that the imaging of defects using BCDI could be of significant importance for giant magnetoresistance devices, like hard disk-drive read heads, where the presence of dislocations can affect magnetic domain wall pinning and coercivity.

scholarly journals Ultrasound-assisted method to improve the structure of CeO2@polyprrole core-shell nanosphere and its photocatalytic reduction of hazardous Cr6+

2019 ◽  
Vol 59 ◽  
pp. 104738 ◽  
Author(s):  
Vellaichamy Balakumar ◽  
Hyungjoo Kim ◽  
Ramalingam Manivannan ◽  
Hyorim Kim ◽  
Ji Won Ryu ◽  
...  
Keyword(s):  
Photocatalytic Reduction ◽  
Core Shell ◽  
Ultrasound Assisted

scholarly journals Integration of Horizontal and Vertical Microfluidic Modules for Core-Shell Droplet Generation and Chemical Application

Micromachines ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 613 ◽  
Author(s):  
Dong Hyun Yoon ◽  
Yoshito Nozaki ◽  
Daiki Tanaka ◽  
Tetsushi Sekiguchi ◽  
Shuichi Shoji
Keyword(s):  
Inner Core ◽  
Three Dimensional ◽  
Vertical Plane ◽  
Droplet Generation ◽  
Microfluidic Channels ◽  
Core Shell ◽  
Water Droplets ◽  
Device Structure ◽  
Chemical Application ◽  
Oil In Water

This paper presents a method for utilizing three-dimensional microfluidic channels fully to realize multiple functions in a single device. The final device structure was achieved by combining three independent modules that consisted of horizontal and vertical channels. The device allowed for the one-step generation of water-in-oil-in-water droplets without the need for partial treatment of the polydimethylsiloxane channel surface using separate modules for generating water-in-oil droplets on the horizontal plane and oil-in-water droplets on the vertical plane. The second vertically structured module provided an efficient flow for the generation of highly wettable liquid droplets, and tuning of the first horizontally structured module enabled different modes of inner-core encapsulation within the oil shell. The successful integration of the vertical and horizontal channels for core-shell droplet generation and the chemical synthesis of a metal complex within the droplets were evaluated. The proposed approach of integrating independent modules will expand and enhance the functions of microfluidic platforms.

Sign in / Sign up

Export Citation Format

Share Document