Core-shell meso-beta@mesoporous aluminosilicate supported Ni2P catalyst for the hydrodenitrogenation of quinoline: Effect of core shell structure on Ni2P particle size

SiCp reinforced aluminium matrix composites (AMCs), which are widely used in the aerospace, automotive, and electronic packaging fields along with others, are usually prepared by ex situ techniques. However, interfacial contamination and poor wettability of the ex situ techniques make further improvement in their comprehensive performance difficult. In this paper, SiCp reinforced AMCs with theoretical volume fractions of 15, 20, and 30% are prepared by powder metallurgy and in situ reaction via an Al-Si-C system. Moreover, a combined method of external addition and an in situ method is used to investigate the synergistic effect of ex situ and in situ SiCp on AMCs. SiC particles can be formed by an indirect reaction: 4Al + 3C → Al4C3 and Al4C3 + 3Si → 3SiC + 4Al. This reaction is mainly through the diffusion of Si, in which Si diffuses around Al4C3 and then reacts with Al4C3 to form SiCp. The in situ SiC particles have a smooth boundary, and the particle size is approximately 1–3 μm. A core-shell structure having good bonding with an aluminium matrix was generated, which consists of an ex situ SiC core and an in situ SiC shell with a thickness of 1–5 μm. The yield strength and ultimate tensile strength of in situ SiCp reinforced AMCs can be significantly increased with a constant ductility by adding 5% ex situ SiCp for Al-28Si-7C. The graphite particle size has a significant effect on the properties of the alloy. A criterion to determine whether Al4C3 is a complete reaction is achieved, and the forming mechanism of the core-shell structure is analysed.

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Synthesis and Characterization of PBA/aPS Core-Shell Latex Particles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.631-632.588 ◽

2013 ◽

Vol 631-632 ◽

pp. 588-591

Author(s):

Ming Jue Li ◽

Ying Yan Diao ◽

Xi Jun Liu

Keyword(s):

Particle Size ◽

Shell Structure ◽

Average Particle Size ◽

Morphological Structure ◽

Shell Morphology ◽

Polymerization Process ◽

Core Shell ◽

Average Particle ◽

Latex Particles ◽

Core Shell Structure

The core-shell structure copolymer of PBA/PS was prepared using pre-emulsion and semi-continues polymerization process. The particle size of core-shell latex and the St conversion of shell monomer were affected by emulsifier, initiator, pH and temperature etc. Meanwhile, the laser particle size analyzer, transmission electron microscope and other test methods were utilized to study latex particle average particle size, size distribution and morphological structure, respectively. The kinetics of polymerization was investigated. Well-defined core-shell structure and narrow particle sizedistribution could be achieved under starved conditions of monomer feeding. By the means of TEM found that PBA/PS latex particles had clearly core/shell morphology.

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Dually Cross-Linked Core-Shell Structure Nanohydrogel with Redox–Responsive Degradability for Intracellular Delivery

Pharmaceutics ◽

10.3390/pharmaceutics13122048 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2048

Author(s):

Siyuan Deng ◽

Maria Rosa Gigliobianco ◽

Yimin Mijiti ◽

Marco Minicucci ◽

Manuela Cortese ◽

...

Keyword(s):

Particle Size ◽

Hyaluronic Acid ◽

Cytochrome C ◽

Horseradish Peroxidase ◽

Shell Structure ◽

Intracellular Delivery ◽

Core Shell ◽

Hydroxypropyl Methacrylamide ◽

Redox Responsive ◽

Core Shell Structure

A redox-responsive nanocarrier is a promising strategy for the intracellular drug release because it protects the payload, prevents its undesirable leakage during extracellular transport, and favors site-specific drug delivery. In this study, we developed a novel redox responsive core-shell structure nanohydrogel prepared by a water in oil nanoemulsion method using two biocompatible synthetic polymers: vinyl sulfonated poly(N-(2-hydroxypropyl) methacrylamide mono/dilactate)-polyethylene glycol-poly(N-(2-hydroxypropyl) methacrylamide mono/dilactate) triblock copolymer, and thiolated hyaluronic acid. The influence on the nanohydrogel particle size and distribution of formulation parameters was investigated by a three-level full factorial design to optimize the preparation conditions. The surface and core-shell morphology of the nanohydrogel were observed by scanning electron microscope, transmission electron microscopy, and further confirmed by Fourier transform infrared spectroscopy and Raman spectroscopy from the standpoint of chemical composition. The redox-responsive biodegradability of the nanohydrogel in reducing environments was determined using glutathione as reducing agent. A nanohydrogel with particle size around 250 nm and polydispersity index around 0.1 is characterized by a thermosensitive shell which jellifies at body temperature and crosslinks at the interface of a redox-responsive hyaluronic acid core via the Michael addition reaction. The nanohydrogel showed good encapsulation efficiency for model macromolecules of different molecular weight (93% for cytochrome C, 47% for horseradish peroxidase, and 90% for bovine serum albumin), capacity to retain the peroxidase-like enzymatic activity (around 90%) of cytochrome C and horseradish peroxidase, and specific redox-responsive release behavior. Additionally, the nanohydrogel exhibited excellent cytocompatibility and internalization efficiency into macrophages. Therefore, the developed core-shell structure nanohydrogel can be considered a promising tool for the potential intracellular delivery of different pharmaceutical applications, including for cancer therapy.

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Design of Novel Nanocomposites through Interfacial Engineering

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.23.327 ◽

2005 ◽

Vol 23 ◽

pp. 327-330

Author(s):

S. Sindhu ◽

S. Jegadesan ◽

R. Renu ◽

S. Valiyaveettil

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Shell Structure ◽

Magnetic Particles ◽

Core Shell ◽

The Novel ◽

Interfacial Engineering ◽

The Matrix ◽

Core Shell Structure ◽

Analytical Tools

Two classes of nanocomposites involving polymers and magnetic particles or silica were synthesized and characterized. Effect of polymer on the morphology of the composites and the matrix filler interactions were studied in detail. Different analytical tools were used to characterize these composites and show a core-shell structure for the novel nanocomposites reported in this paper. TEM studies on these composites gave particle size distribution in nanometer range. The morphology and size of the particle changed significantly with the polymer used.

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Preparation and Characterization of Core-Shell Type Versatate-Fluorocarbon Emulsion

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.183-185.2055 ◽

2011 ◽

Vol 183-185 ◽

pp. 2055-2058

Author(s):

Xiao Hui Gao ◽

Yu Feng Li ◽

Zhou Mao Yu

Keyword(s):

Contact Angle ◽

Particle Size ◽

Shell Structure ◽

Raw Materials ◽

Core Shell ◽

Seeded Emulsion Polymerization ◽

Hard Shell ◽

Fluorocarbon Emulsion ◽

Core Shell Structure ◽

Organic Fluorine

Versatate-fluorocarbon emulsion with core-shell structure was synthesized by seeded emulsion polymerization using versatate, organic fluorine and acrylate as raw materials. The influences of amount of organic fluorine and versatate, core-shell ratio on the properties of emulsion were discussed. The emulsion was characterized with contact angle analyzer, particle size, transmission electron microscopy (TEM), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The results showed that the emulsion had good properties while w(organic fluorine)=6%, w(versatate)=8%, soft core-hard shell and w(core):w(shell)=3:2. The particle size is 110nm and with core-shell structure. The contact angle of emulsion film to water is 98.1º. The synergistic effect of versatate and fluorocarbon based on core-shell structure improve the over-all properties effectively.

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Reaction Mechanism of Iron-Rich Magnesia-Corundum Composites at 1420°C

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.680.339 ◽

2016 ◽

Vol 680 ◽

pp. 339-342 ◽

Cited By ~ 1

Author(s):

Hao Bo Zhang ◽

Yong Li ◽

Jia Lin Sun ◽

Shuo Cao ◽

Yong Qiang Sun ◽

...

Keyword(s):

Solid Solution ◽

Particle Size ◽

Reaction Mechanism ◽

Low Temperature ◽

Shell Structure ◽

Core Shell ◽

Spinel Solid Solution ◽

Core Shell Structure ◽

Periclase Material

Specimens were prepared by using iron-rich magnesia and high-pure magnesia as the main starting materials, and introducing fused corundum of 3%(in mass), 6%, 9%, 12%, 15% respectively and sintered at 1420°C.The samples were characterized by XRD and SEM. The results show that in-situ synthesized composite spinel solid solution were formed in the reaction between iron-rich magnesia and fused corundum. Iron oxides play a key role on the formation of spinel solid solution. When fused corundum was added in a certain particle size, the material showed core-shell structure. Outer layer of core-shell structure were spinel solid solution and the inside were corundum. These core-shell structure make the synthesis of spinel solid solution bonded periclase material at low temperature happen.

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