scholarly journals Highly Efficient Mesoporous Core-Shell Structured Ag@SiO2 Nanosphere as an Environmentally Friendly Catalyst for Hydrogenation of Nitrobenzene

Nanomaterials ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 883
Author(s):  
Bonan Zhao ◽  
Zhipeng Dong ◽  
Qiyan Wang ◽  
Yisong Xu ◽  
Nanxia Zhang ◽  
...  
Keyword(s):  
Environmentally Friendly ◽  
Mesoporous Structure ◽  
Core Shell ◽  
Core Size ◽  
One Pot ◽  
The Core ◽  
Different Types ◽  
The Stability ◽  
Catalytic Performances ◽  
The Ideal

The size-uniformed mesoporous Ag@SiO2 nanospheres’ catalysts were prepared in one-pot step via reducing AgNO3 by different types of aldehyde, which could control the size of Ag@SiO2 NPs and exhibit excellent catalytic activity for the hydrogenation of nitrobenzene. The results showed that the Ag core size, monitored by different aldehydes with different reducing abilities, together with the ideal monodisperse core-shell mesoporous structure, was quite important to affect its superior catalytic performances. Moreover, the stability of Ag fixed in the core during reaction for 6 h under 2.0 MPa, 140 °C made this type of Ag@SiO2 catalyst separable and environmentally friendly compared with those conventional homogeneous catalysts and metal NPs catalysts. The best catalyst with smaller Ag cores was prepared by strong reducing agents such as CH2O. The conversion of nitrobenzene can reach 99.9%, the selectivity was 100% and the catalyst maintained its activity after several cycles, and thus, it is a useful novel candidate for the production of aniline.

Core–shell stability of nanoparticles plays an important role for overcoming the intestinal mucus and epithelium barrier

2016 ◽  
Vol 4 (35) ◽  
pp. 5831-5841 ◽  
Author(s):  
Min Liu ◽  
Lei Wu ◽  
Xi Zhu ◽  
Wei Shan ◽  
Lian Li ◽  
...  
Keyword(s):  
Shell Structure ◽  
Core Shell ◽  
The Core ◽  
Shell Stability ◽  
Intestinal Mucus ◽  
Core Shell Structure ◽  
The Stability

The stability of the core–shell structure plays an important role in the nanoparticles ability to overcome both the mucus and epithelium absorption barrier.

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).

Core@shell nanostructured Au-d@NimPtm for electrochemical oxygen reduction reaction: effect of the core size and shell thickness

2019 ◽  
Vol 9 (17) ◽  
pp. 4668-4677 ◽  
Author(s):  
Min Zhang ◽  
Shu Miao ◽  
Bo-Qing Xu
Keyword(s):  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Shell Thickness ◽  
Reduction Reaction ◽  
Core Shell ◽  
Core Size ◽  
The Core ◽  
Electrocatalytic Performance ◽  
Electrochemical Oxygen

Au-d@NimPtm nanostructures are studied to address the effects of the Au-core size (d) and NiPt-shell thickness (m) on the electrocatalytic performance of Pt for the ORR.

scholarly journals Indium Phosphide-Based Semiconductor Nanocrystals and Their Applications

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Paul Mushonga ◽  
Martin O. Onani ◽  
Abram M. Madiehe ◽  
Mervin Meyer
Keyword(s):  
Indium Phosphide ◽  
Surface Passivation ◽  
Semiconductor Nanocrystals ◽  
Core Size ◽  
The Core ◽  
Colloidal Semiconductor Nanocrystals ◽  
Biological Studies ◽  
Fluorescent Materials ◽  
Different Types ◽  
Heating Up

Semiconductor nanocrystals or quantum dots (QDs) are nanometer-sized fluorescent materials with optical properties that can be fine-tuned by varying the core size or growing a shell around the core. They have recently found wide use in the biological field which has further enhanced their importance. This review focuses on the synthesis of indium phosphide (InP) colloidal semiconductor nanocrystals. The two synthetic techniques, namely, the hot-injection and heating-up methods are discussed. Different types of the InP-based QDs involving their use as core, core/shell, alloyed, and doped systems are reviewed. The use of inorganic shells for surface passivation is also highlighted. The paper is concluded by some highlights of the applications of these systems in biological studies.

scholarly journals Design and fabrication of 125I seeds for brachytherapy using capillary-based microfluidic technique

Nukleonika ◽  
2021 ◽  
Vol 66 (2) ◽  
pp. 55-60
Author(s):  
Yuan Wang ◽  
Miao Zhang ◽  
Tong Song ◽  
Zhenqi Chang
Keyword(s):  
Monte Carlo ◽  
Dose Distribution ◽  
Core Shell ◽  
Core Size ◽  
The Core ◽  
125I Seeds ◽  
Transport Code ◽  
Core Shell Structure ◽  
Brachytherapy Source ◽  
Microfluidic Technique

Abstract A new kind of 125I seeds with a core-shell structure were synthesized by an easy assembling–disassembling coaxial capillaries microfluidic device. The dose distribution of a 125I brachytherapy source fabricated by arranging six 125I seeds collinearly within a cylindrical titanium capsule was simulated by modelling the source in a water phantom using Monte Carlo N-Particle Transport code. The influence of the motion and the core size of the 125I seeds on the dose distribution was also studied in this work.

Dependence of Relaxation Time on the Core Size Two-Phase Nanoparticles Magnetite/Titanomagnetite

2015 ◽  
Vol 752-753 ◽  
pp. 418-421
Author(s):  
Ilia Iliushin ◽  
Leonid Afremov ◽  
Sergey Anisimov
Keyword(s):  
Relaxation Time ◽  
Blocking Temperature ◽  
Exchange Constant ◽  
Core Shell ◽  
Core Size ◽  
Shell Nanoparticles ◽  
Two Phase ◽  
The Core ◽  
Core Shell Nanoparticles ◽  
Model Nanoparticles

In this paper, depending of the blocking temperature on magnetite core size for core/shell nanoparticles has been carried out using our theoretical model. Nanoparticles has size of 100nm, and magnetite core increases from 0nm to 100nm. Systems were studied with different values of exchange constant. The data obtained indicate that exchange constant increases the blocking temperature. However, the sign of the constant does not matter.

Research on Gap Adjustment for Offset Printing Machine Based on ARM

2013 ◽  
Vol 364 ◽  
pp. 290-293
Author(s):  
Zhen Qing Gao ◽  
Han Xu Sun
Keyword(s):  
Control System ◽  
Automatic Control ◽  
Control Program ◽  
Offset Printing ◽  
Improve Performance ◽  
The Core ◽  
Hardware System ◽  
The Stability ◽  
Printing Machine ◽  
The Ideal

Many problems exist in traditional gap adjusting for offset printing machine, so an automatic regulating technology is proposed. In the course of this research, the hardware system of the gap adjusting is designed by the embedded ARM controller as the core of the automatic control system, the developing process of the ARM control program is illustrated. The method for automatically adjusting the gap can simplify the operation, improve performance of the offset press, improve the stability and reliability of the offset printing process, and has a certain practical value, and has obtained the ideal effect.

Insight into growth of Au–Pt bimetallic nanoparticles: anin situXAS study

2017 ◽  
Vol 24 (4) ◽  
pp. 825-835 ◽  
Author(s):  
Chandrani Nayak ◽  
D. Bhattacharyya ◽  
K. Bhattacharyya ◽  
A. K. Tripathi ◽  
R. D. Bapat ◽  
...  
Keyword(s):  
Bimetallic Nanoparticles ◽  
Energy Dispersive ◽  
Core Shell ◽  
One Pot ◽  
X Ray ◽  
The Core ◽  
One Pot Synthesis ◽  
X Ray Absorption ◽  
Insight Into

Au–Pt bimetallic nanoparticles have been synthesized through a one-pot synthesis route from their respective chloride precursors using block copolymer as a stabilizer. Growth of the nanoparticles has been studied by simultaneousin situmeasurement of X-ray absorption spectroscopy (XAS) and UV–Vis spectroscopy at the energy-dispersive EXAFS beamline (BL-08) at Indus-2 SRS at RRCAT, Indore, India.In situXAS spectra, comprising both X-ray near-edge structure (XANES) and extended X-ray absorption fine-structure (EXAFS) parts, have been measured simultaneously at the Au and PtL3-edges. While the XANES spectra of the precursors provide real-time information on the reduction process, the EXAFS spectra reveal the structure of the clusters formed in the intermediate stages of growth. This insight into the formation process throws light on how the difference in the reduction potential of the two precursors could be used to obtain the core–shell-type configuration of a bimetallic alloy in a one-pot synthesis method. The core–shell-type structure of the nanoparticles has also been confirmed byex situenergy-dispersive spectroscopy line-scan and X-ray photoelectron spectroscopy measurements within situion etching on fully formed nanoparticles.

Emulsifier-Free Core-Shell Hybrid Latexes from Castor Oil-Based Waterborne Polyurethane and Polyacrylate Containing Fluorine and Silicon

2013 ◽  
Vol 690-693 ◽  
pp. 1620-1623 ◽  
Author(s):  
Chang Qing Fu ◽  
Meng Xu ◽  
Zheng Yang ◽  
Qing Gui Lv ◽  
Liang Shen
Keyword(s):  
Contact Angle ◽  
Castor Oil ◽  
Waterborne Polyurethane ◽  
Core Shell ◽  
One Pot ◽  
Water Contact ◽  
Functional Monomers ◽  
The Core ◽  
Air Interface ◽  
Transmission Electron

The core-shell polyurethane-acrylate(PUA) emulsion containing fluorine and silicon in the core was synthesized by “one-pot” emulsion polymerization in the presence of castor oil-based polyurethane without traditional emulsifier, using methyl methacrylate (MMA), butyl acrylate (BA) as the main monomers, dodecafluoroheptyl methacrylate (G04), γ-methacryloxy propyl trimethoxyl silane (KH-570) as the functional monomers. The structure and properties of the fluorinated-silicated PUA and their films were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectrum (FT-IR) and contact angle testing. The results showed that fluorine and silicon monomers had effectively copolymerized with acrylic monomers and a core-shell structure in the latex was formed. The water contact angle for film-air interface is 92.5o, and the cetane contact angle for film-air interface is 47.5 o.

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