The Fabrication and Progress of Core-Shell Composite Materials

2009 ◽  
Vol 62 (12) ◽  
pp. 1561 ◽  
Author(s):  
Shunsheng Cao ◽  
Juanrong Chen ◽  
Jie Hu
Keyword(s):  
Materials Science ◽  
Chemical Properties ◽  
Core Shell ◽  
Production Methods ◽  
Potential Applicability ◽  
Shell Particles ◽  
The Stability ◽  
Physical And Chemical ◽  
Shell Composite ◽  
Organic Particle

Core-shell materials, in which a layer or multilayer of inorganic or organic material surrounds an inorganic or organic particle core, have been investigated both as a means to improve the stability and surface chemistry of the core particle and as a way of accessing unique physical and chemical properties that are not possible from one material alone. As a result, the fabrication of core-shell particles is attracting a great deal of interest because of their unique properties and potential applicability in catalysis, semiconductors, drug delivery, enzyme immobilization, molecular recognition, chemical sensing, etc. As evidenced by the literature described and discussed in this review, a basic understanding of the mechanism and recent progress in production methods have enabled the fabrication of core-shell particles with unique and tailored properties for various applications in materials science.

Magnetic Properties of Fe3O4/CoFe2O4 Composite Nanoparticles with Core/Shell Architecture

2020 ◽  
Vol 65 (10) ◽  
pp. 904
Author(s):  
V. O. Zamorskyi ◽  
Ya. M. Lytvynenko ◽  
A. M. Pogorily ◽  
A. I. Tovstolytkin ◽  
S. O. Solopan ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Spinel Ferrite ◽  
Composite Nanoparticles ◽  
Core Shell ◽  
Cofe2o4 Nanoparticles ◽  
Core Diameter ◽  
The Core ◽  
Shell Particles ◽  
Interface Parameters ◽  
Shell Composite

Magnetic properties of the sets of Fe3O4(core)/CoFe2O4(shell) composite nanoparticles with a core diameter of about 6.3 nm and various shell thicknesses (0, 1.0, and 2.5 nm), as well as the mixtures of Fe3O4 and CoFe2O4 nanoparticles taken in the ratios corresponding to the core/shell material contents in the former case, have been studied. The results of magnetic research showed that the coating of magnetic nanoparticles with a shell gives rise to the appearance of two simultaneous effects: the modification of the core/shell interface parameters and the parameter change in both the nanoparticle’s core and shell themselves. As a result, the core/shell particles acquire new characteristics that are inherent neither to Fe3O4 nor to CoFe2O4. The obtained results open the way to the optimization and adaptation of the parameters of the core/shell spinel-ferrite-based nanoparticles for their application in various technological and biomedical domains.

Targeted Alternation in Properties of Solid Amorphous-Nanocrystalline Material in Exposing to Nanosecond Laser Radiation

2021 ◽  
Vol 410 ◽  
pp. 469-474
Author(s):  
Ivan S. Safronov ◽  
Alexander I. Ushakov
Keyword(s):  
Laser Radiation ◽  
Physical Properties ◽  
Materials Science ◽  
Chemical Properties ◽  
High Energy ◽  
Strength Properties ◽  
Nanosecond Laser ◽  
Processing Modes ◽  
Traditional Processing ◽  
Physical And Chemical

One of the most important purposes of materials science is the ability to govern the physical properties of materials characterized by different structures. The strength properties of nanostructured metal alloys do not always meet the exploitation requirements. The set of properties of such materials is stable within narrow limits: temperature, mechanical, and corrosion conditions. Traditional processing modes are ineffective for such materials. Attempts to use them often lead to the loss of unique physical and chemical properties. The most effective methods of processing such materials are associated with the use of laser radiation. The laser pulse has a number of features, including a complex effect on the surface layers of the material. Spot and short irradiation with high-energy rays can preserve the unique physical properties of samples as a whole and improve strength indicators without destroying the structure of the material as a whole.

Preparation of Core-Shell Particles Consisted of Polysiloxane and Styrene-Butyl Methacrylate by High Internal Phase Emulsion

2014 ◽  
Vol 1033-1034 ◽  
pp. 996-1001
Author(s):  
Shao Jin Jia ◽  
Zhen Qi Zhang ◽  
Zhen Gang Ding ◽  
Xiao Tian Hou ◽  
Ping Kai Jiang
Keyword(s):  
Weight Ratio ◽  
Continuous Phase ◽  
Butyl Methacrylate ◽  
Core Shell ◽  
Water Contact ◽  
High Internal Phase Emulsion ◽  
Transmission Electron ◽  
Internal Phase ◽  
Shell Particles ◽  
Shell Composite

A core-shell composite polymer was produced by the method of high internal phase emulsion polymerization. The continuous phase of emulsion contained styrene(St), butyl methacrylate(BMA), octamethylcylotetrasiloxane(D4), and azobisisobutyronitrile (AIBN) which worked as an initiator. The block copolymers with St, BMA, D4 units are particularly promising for surface modification and hydrophobicity. The core-shell structure is proved by the use of Transmission electron microscopy (TEM). In addition, the water contact angle increased with the increasing weight ratio of D4. The results show that the concentrated emulsion system has good stability and the water resistance of the polymer has been improved greatly.

Effect of glycidyl methacrylate (GMA) on the stability of acrylic latex

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Guangfeng Wu ◽  
Yue Tao ◽  
Hong Kang ◽  
Huixuan Zhang
Keyword(s):  
Experimental Data ◽  
Glycidyl Methacrylate ◽  
Sodium Dodecyl ◽  
The Other ◽  
Lower Amount ◽  
Core Shell ◽  
Acrylic Latex ◽  
The Core ◽  
Shell Particles ◽  
The Stability

AbstractThe stability of core-shell particles (CSPs) with butyl acrylate (BA) as the core and methyl methacrylate (MMA)/glycidyl methacrylate (GMA) mixture in various compositions as the shell was investigated by turbidity measurements. The experiments demonstrate that lower amount addition of GMA could not improve the latex stability. When the amount of GMA exceeded 2% of the total reactants, it began to improve the stability of the latex. With the increasing content of GMA, the latex became more and more stable. On the other hand, experimental data also show that the stability was improved by increasing the concentration of sodium dodecyl sulfate (SDS).

scholarly journals Basic Materials Studies of Lanthanide Halide Scintillators

2007 ◽  
Vol 1038 ◽  
Author(s):  
F. P. Doty ◽  
Douglas McGregor ◽  
Mark Harrison ◽  
Kip Findley ◽  
Raulf Polichar ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Materials Science ◽  
Low Cost ◽  
Large Diameter ◽  
Scale Up ◽  
Chemical Properties ◽  
Anisotropic Plasticity ◽  
Ongoing Work ◽  
Perfect Cleavage ◽  
Physical And Chemical

AbstractCerium and lanthanum tribromides and trichlorides form isomorphous alloys with the hexagonal UCl3 type structure, and have been shown to exhibit high luminosity and proportional response, making them attractive alternatives for room temperature gamma ray spectroscopy. However the fundamental physical and chemical properties of this system introduce challenges for material processing, scale-up, and detector fabrication. In particular, low fracture stress and perfect cleavage along prismatic planes cause profuse cracking during and after crystal growth, impeding efforts to scale this system for production of low cost, large diameter spectrometers. We have reported progress on basic materials science of the lanthanide halides. Studies to date have included thermomechanical and thermogravimetric analyses, hygroscopicity, yield strength, and fracture toughness. The observed mechanical properties pose challenging problems for material production and post processing; therefore, understanding mechanical behavior is key to fabricating large single crystals, and engineering of robust detectors and systems. Analysis of the symmetry and crystal structure of this system, including identification of densely-packed and electrically neutral planes with slip and cleavage, and comparison of relative formation and propagation energies for proposed slip systems, suggest possible mechanisms for deformation and crack initiation under stress. The low c/a ratio and low symmetry relative to traditional scintillators indicate limited and highly anisotropic plasticity cause redistribution of residual process stress to cleavage planes, initiating fracture. Ongoing work to develop fracture resistant lanthanide halides is presented.

Synthesis and Kinetic Investigations for the Isomerization Process of 2–Hydroxy Chalcone Derivatives

2019 ◽  
Vol 41 (6) ◽  
pp. 1046-1046
Author(s):  
Omar A Shareef Omar A Shareef ◽  
Said A Said and Ali Y Abdulrazaq Said A Said and Ali Y Abdulrazaq
Keyword(s):  
Biological Activities ◽  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Pseudo First Order Reaction ◽  
First Order ◽  
Steric Factors ◽  
Kinetic Investigations ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

The wide biological activities of flavanones are mainly depends on their physical and chemical properties, thus a number of substituted 2-Hydroxy chalcones have been synthesized, and their isomerization to their corresponding flavanones was studied. In order to determine the rate constant, kinetic experiments were performed using HPLC technique in (9:1) (CH3CN:H2O) medium at different temperature (298-318) K. The obtained results were interpreted by four steps mechanism, which considered the existence of phenoxide ion as the key intermediate. This study performed with a pseudo first order ( reaction in which the rate for the studied compounds follow the sequence 5 andgt; 2 andgt; 1 andgt; 4 andgt; 3, the activation energy have the same sequence for these compounds .The effect of substituents on the rate showed that electronic and steric factors play reasonable role on the stability of the product .

The Establishment of the 3rd National Reference Standard for Tachypleus Tridentatus Lysate

2017 ◽  
Vol 6 (3) ◽  
pp. 50
Author(s):  
Tong Cai ◽  
Guolai Zhang ◽  
Yusheng Pei ◽  
Hua Gao
Keyword(s):  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Reference Standard ◽  
Tachypleus Tridentatus ◽  
National Reference ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

<p><strong>Objective</strong>  To establish the 3rd national reference standard for Tachypleus Tridentatus Lysate Reagent. <strong>Method</strong> <strong>and Results</strong>  The candidates of reference standard were studied for the physical and chemical properties, and the stability. To determined its sensitivity by collaboration calibration. <strong>Conclusions</strong>  The sensitivity of the 3rd national reference standard for TAL is 0.06EU / ml, lot number is 150603-201003.</p>

Salting-out and salting-in experiments with lignosulfonates (LSs)

Holzforschung ◽  
2013 ◽  
Vol 67 (5) ◽  
pp. 549-557 ◽  
Author(s):  
Bernt O. Myrvold
Keyword(s):  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Salting Out ◽  
Practical Applications ◽  
Common Ion ◽  
The Common ◽  
Common Ion Effect ◽  
The Stability ◽  
Physical And Chemical ◽  
And Chemical Properties

Abstract The solubility of lignosulfonates (LSs) in water is strongly dependent on other ions present in the water phase. The differences in the solubility might strongly influence the measurements of the physical and chemical properties of the LS molecules. A reduced solubility of the LS might also affect its utility in many practical applications. The understanding of the interaction between LSs and various salts is important for both practical and theoretical reasons. Therefore, the effect of salt concentrations on the LS has been investigated for 41 different salts with 14 different cations and 16 different anions. The observations cannot be explained by the common ion effect or the screening effects. On the contrary, it was found that the stability of LS solutions follows the Hofmeister series, with the exception of those ions that will chemically interact with the LS molecule. Moreover, the positions of phosphate (HPO42-) and sulfate (SO42-) ions were reversed.

Physico-Chemical Properties of Silica Coated Superparamagnetic Magnetite Nanoparticles Synthesized by Non-Seeded Process

2015 ◽  
Vol 1107 ◽  
pp. 267-271
Author(s):  
Sodipo Bashiru Kayode ◽  
Azlan Abdul Aziz
Keyword(s):  
Silica Nanoparticles ◽  
Magnetite Nanoparticles ◽  
Colloidal Suspension ◽  
Sol Gel ◽  
Chemical Properties ◽  
Colloidal Suspensions ◽  
Core Shell ◽  
Shell Nanoparticles ◽  
Physico Chemical ◽  
Physical And Chemical

The science of core-shell nanoparticles requires investigation into several physical and chemical properties of the composite nanoparticles. Unlike the conventional sol-gel or the reverse microemulsion micelle method, we presented here a non-seeded process of encapsulating superparamagnetic magnetite nanoparticles (SPMN) with silica. Physico-chemical analysis of the product was used to confirm the result of the coating procedure. Colloidal suspension of SPMN and silica nanoparticles were synthesised through coprecipitation method and modified Stöber method respectively. Afterwards, both colloidal suspensions of SPMN and silica nanoparticles were sonicated to encapsulate the SPMN with silica. Elemental mapping of the composite particles with electron spectroscopy imaging (ESI) confirmed the core-shell micrograph of the SPMN and silica. The X-ray diffraction pattern (XRD) showed the silica shell to be in amorphous form. FTIR analysis further confirmed the chemical properties of the product to be silica coated SPMN.

scholarly journals Review of Research on Template Methods in Preparation of Nanomaterials

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Yadian Xie ◽  
Duygu Kocaefe ◽  
Chunying Chen ◽  
Yasar Kocaefe
Keyword(s):  
Chemical Properties ◽  
Synthetic Methods ◽  
Soft Template ◽  
Template Method ◽  
Hard Template ◽  
Production Methods ◽  
Different Types ◽  
Physical And Chemical ◽  
Particle Size And Structure ◽  
And Chemical Properties

The nanomaterials have been widely used in various fields, such as photonics, catalysis, and adsorption, because of their unique physical and chemical properties. Therefore, their production methods are of utmost importance. Compared with traditional synthetic methods, the template method can effectively control the morphology, particle size, and structure during the preparation of nanomaterials, which is an effective method for their synthesis. The key for the template method is to choose different templates, which are divided into hard template and soft template according to their different structures. In this paper, the effects of different types of templates on the morphology of nanomaterials during their preparation are investigated from two aspects: hard template and soft template, combined with the mechanism of action.

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