scholarly journals Preparation and characterization of CuO/Muscovite flakes pearlescent pigment with UV absorption and high NIR reflectance

2019 ◽  
Vol 2 (2) ◽  
pp. 265-270
Author(s):  
Yuksel AKINAY ◽  
Ihsan Nuri AKKUŞ
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Near Infrared ◽  
Sol Gel ◽  
Cuo Nanoparticles ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Ultraviolet Shielding ◽  
Pearlescent Pigment

The CuO nanoparticles were deposited onto muscovite flakes using sol-gel methods. The thermal, conductivity, optic and structural properties of obtained pigments (CuO/Muscovite) were studied. Hence, the prepared pigments were characterized via using scanning electronic microscopy (SEM) and ultraviolet–visible spectrophotometer (UV-Vis). The results show that CuO was coated on the surface of muscovite flakes uniformly. The obtained pigments show the more stable thermal properties than those obtained from undeposited flakes. The CuO/Muscovite pigments showed high ultraviolet shielding performance. In addition that CuO/Muscovite pigments exhibited higher near-infrared (NIR) reflectance than those of pure-CuO.

scholarly journals Analysis of the properties of a Cu-Al2-O3 sintered system based on ultra fine and nanocomposite powders

2007 ◽  
Vol 39 (2) ◽  
pp. 145-152 ◽  
Author(s):  
Z. Andjic ◽  
M. Korac ◽  
Z. Kamberovic ◽  
A. Vujovic ◽  
M. Tasic
Keyword(s):  
Mechanical Properties ◽  
Chemical Method ◽  
Elevated Temperatures ◽  
Hydrogen Atmosphere ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
Composite Powders ◽  
Nanocomposite Powders ◽  
Final Composition

In this paper synthesis of a composite based on Cu-Al2O3 by a thermo-chemical method is shown along with a comparative analysis of the properties of the obtained nanocomposite sintered samples, which are characterized by a good combination of electric-mechanical properties, suitable for work at elevated temperatures. Ultra fine and nanocrystal powder Cu-Al2O3 is obtained by a chemical method, starting from water solutions of nitrates up to achieving the requested composition with 3 and 5% of Al2O3. Synthesis of composite powders has been developed through several stages: drying by spraying, oxidation of the obtained powder of precursor and then reduction by hydrogen until the final composition of nanocomposite powder is achieved. After characterization of the obtained powders, which comprised examination by the Scanning Electronic Microscopy (SEM) method and X-ray-structure analysis (RDA), the powders were compacted with compacting pressure of 500 MPa. Sintering of the obtained samples was performed in the hydrogen atmosphere in isothermal conditions at temperatures of 800 and 900oC for 30, 60, 90 and 120 minutes. Characterization of the obtained Cu-Al2O3 of the nanocomposite sintered system comprised examination of microstructure by the Scanning Electronic Microscopy (SEM), as well as examining of electric mechanical properties. The obtained results show a homogenous distribution of dispersoides in the structure, as well as good mechanical and electric properties. .

Characterization of Shivirtui Zeolite Modified with Aluminum Oxyhydroxide Nanofibers

2019 ◽  
Vol 942 ◽  
pp. 40-49
Author(s):  
Yulia Murashkina ◽  
Olga B. Nazarenko
Keyword(s):  
Chemical Properties ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Aluminum Oxyhydroxide

Natural zeolite of Shivirtui deposit (Russia) was modified with nanofibers of aluminum oxyhydroxide AlOOH. Aluminum oxyhydroxide nanofibers were produced at the heating and oxidation of aluminum powder with water. The properties of modified zeolite were investigated by means of X-ray diffraction, transmission electronic microscopy, scanning electronic microscopy, low-temperature nitrogen adsorption, thermal analysis, and Fourier transform infrared spectroscopy. It was found that water content in the modified sample of zeolite was about 15 %. Based on the study of the physical and chemical properties, shivirtui zeolite modified with nanofibers of aluminum oxyhydroxide can be proposed for use as a flame-retardant additive to polymers.

scholarly journals Improving anti-infrared radiation and heat insulation by potassium hexatitanate whisker-doped Al 2 O 3 –SiO 2 composite xerogel

2018 ◽  
Vol 5 (12) ◽  
pp. 180787
Author(s):  
Liang Furong ◽  
Liu Weijun ◽  
Han Xiuxiu ◽  
Zhang Boru ◽  
Zhang Shuhua
Keyword(s):  
Thermal Conductivity ◽  
Infrared Radiation ◽  
Near Infrared ◽  
Raw Materials ◽  
Sol Gel ◽  
Spectral Characteristics ◽  
Molar Ratio ◽  
Thermal Insulating ◽  
Infrared Spectral ◽  
Potassium Hexatitanate

Taking potassium hexatitanate whisker (PTW) modified by silane coupling agent KH550, aluminium nitrate inorganic salt and tetraethyl orthosilicate and deionized water, respectively, as infrared sunscreen, aluminium source and raw materials forming the network structure of a composite xerogel, a series of structurally intact PTW-doped Al 2 O 3 –SiO 2 composite xerogel thermal-insulating materials were prepared by the sol–gel method and dried under atmospheric pressure. The infrared spectral characteristics, infrared radiation transmittance, microstructures, morphology and thermal conductivity of different composite materials prepared have been determined by a Fourier transform infrared spectrometer, UV–visible–near-infrared spectrophotometer, X-ray diffractometer, scanning electron microscope and thermal conductivity tester. The results exhibit that when the Al to Si molar ratio is 1 : 9, the composite material with 5 wt% modified PTW shows the best infrared radiation blocking performance and the lowest thermal conductivity (0.0604 W m −1 K −1 ).

Preparation and characterization of poly(3-glycidoxypropyltrimethoxysilane) nanocomposite using organophilic montmorillonite clay (Mag-cetyltrimethylammonium)

2019 ◽  
Vol 53 (28-30) ◽  
pp. 4313-4322 ◽  
Author(s):  
Nadia Embarek ◽  
Nabahat Sahli ◽  
Mohammed Belbachir
Keyword(s):  
Thermal Properties ◽  
Preparation Method ◽  
X Ray Diffraction ◽  
Scanning Electronic Microscopy ◽  
X Ray ◽  
The Matrix ◽  
Organophilic Clay ◽  
Linear Poly ◽  
Organophilic Montmorillonite

Nanocomposites of linear poly(3-glycidoxypropyltrimethoxysilane) based on Algerian natural organophilic clay: montmorillonite–cetyltrimethylammonium named Maghnite-CTA were prepared by enhancing the dispersion of the matrix polymer in sheets of the organoclay. The effect of the organoclay, used with different amounts (3, 5, and 7% by weight) and the preparation method were studied in order to determine and evaluate their structural, morphological and thermal properties. X-ray diffraction analysis of obtained nanocomposites showed a significant change in the distance interlayer of montmorillonite–cetyltrimethylammonium. Therefore, interlayer expansion and exfoliation of linear poly(3-glycidoxypropyltrimethoxysilane) between layers of montmorillonite–cetyltrimethylammonium were observed. The thermal properties of the prepared nanocomposites were given by thermogravimetric analysis. The structure and morphology of the obtained materials were determined respectively by Fourier transform infrared spectroscopy and scanning electronic microscopy. The results obtained have approved the privilege of the intercalation of linear poly(3-glycidoxypropyltrimethoxysilane) in the interface of montmorillonite–cetyltrimethylammonium and the best quantity of organoclay required to prepare nanocomposite with a high thermal stability is 5% (by weight).

scholarly journals Nanostructured Energetic Materials with Sol-gel Methods

2003 ◽  
Vol 800 ◽  
Author(s):  
Alexander E. Gash ◽  
Joe H. Satcher ◽  
Randall L. Simpson ◽  
Brady J. Clapsaddle
Keyword(s):  
Thermal Properties ◽  
Energetic Materials ◽  
Energetic Material ◽  
Sol Gel ◽  
Small Scale ◽  
Fine Grained ◽  
Electron Microscopies ◽  
Burn Rate ◽  
Scanning Electron

AbstractThe utilization of sol-gel chemical methodology to prepare nanostructured energetic materials as well as the concepts of nanoenergetics is described. The preparation and characterization of two totally different compositions is detailed. In one example, nanostructured aerogel and xerogel composites of sol-gel iron (III) oxide and ultra fine grained aluminum (UFG Al) are prepared, characterized, and compared to a conventional micron-sized Fe2O3/Al thermite. The exquisite degree of mixing and intimate nanostructuring of this material is illustrated using transmission and scanning electron microscopies (TEM and SEM). The nanocomposite material has markedly different energy release (burn rate) and thermal properties compared to the conventional composite, results of which will be discussed. Small-scale safety characterization was performed on the nanostructured thermite. The second nanostructured energetic material consists of a nanostructured hydrocarbon resin fuel network with fine ammonium perchlorate (NH4ClO4) oxidizer present.

Preparation and Characterization of GNP/Nylon Composites

2014 ◽  
Vol 556-562 ◽  
pp. 339-342 ◽  
Author(s):  
Bao Feng Xu ◽  
Zhi Dan Lin ◽  
Jiang Ming Chen ◽  
Jun Lin
Keyword(s):  
Mechanical Properties ◽  
Thermal Conductivity ◽  
Thermal Properties ◽  
Graphene Nanoplatelets ◽  
Melt Blending ◽  
Blending Method

Graphene nanoplatelets (GNP) and nylon (PA) have been often used as thermal filler and matrix and respectively to produce composites. In this work, PA6/PA66/GNP thermal composites were prepared via a melt blending method. Mechanical properties, morphology, and thermal properties of PA6/PA66/GNP composites were investigated. Because the GNP is very expensive, we investigated to use Al2O3 and graphite and examined the characteristics of the prepared composites. Thermal conductivity values of PA6/PA66/GNP composites remarkably increased with increase of GNP contents mainly via layered dispersion in nylon matrix. The thermal conductivity of composite containing 50 wt % of GNP was measured as 5.03 W·m–1·K–1 at 30 °C, indicating an increase of more than 15 times compared with that of the neat PA6. When the Al2O3 was replaced for GNP, the thermal conductivity of composites decreased, but the mechanical properties improved. When graphite was used to replace for GNP, thermal conductivity basically remained unchanged but mechanical properties decreased.

Synthesis and Characterization of Magnetite Particles by Co-Precipitation Method

2012 ◽  
Vol 512-515 ◽  
pp. 82-85 ◽  
Author(s):  
Ming Ya Li ◽  
Xu Dong Sui
Keyword(s):  
Spinel Structure ◽  
Bath Temperature ◽  
Precipitation Method ◽  
Scanning Electronic Microscopy ◽  
Electronic Microscopy ◽  
X Ray ◽  
Magnetite Particles ◽  
Co Precipitation ◽  
Different Diameters

The Fe3O4 nanoparticles with different diameters were prepared by co-precipitation method in this paper. Magnetite particles with different diameters were fabricated by changing the concentration of the reactants and the reaction temperature. The influences of process parameters on the microstructure and properties of magnetic nanopariticles were studied. The obtained samples were characterized by X-ray powder diffraction and scanning electronic microscopy. Besides, vibrating sample magnetmeter was used to characterize the magnetic properties. The results show that all the as-synthesized magnetite nanoparticles are well crystallized and can be indexed into spinel structure. The appearance and magnetism of the particles with different diameter are different from each other. When the ratio of Fe3+ and Fe2+ is 2:1 or 4:3, the product was pure and good crystalline. Furthermore, higher saturation magnetization was obtained in a higher bath temperature.

Structural, Optical, Morphological and Thermal Properties of CuO Nanoparticles Prepared by Sol-gel Technique

2019 ◽  
Vol 11 (5) ◽  
pp. 05011-1-05011-4
Author(s):  
S. C. Vella Durai ◽  
◽  
R. Ganapathi Raman ◽  
E. Kumar ◽  
D. Muthuraj ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Sol Gel ◽  
Cuo Nanoparticles ◽  
Gel Technique

scholarly journals Preparation and characterization of copper oxide nanoparticles and determination of enhancement in critical heat flux

2017 ◽  
Vol 21 (1 Part A) ◽  
pp. 233-242 ◽  
Author(s):  
Jagdeep Kshirsagar ◽  
Ramakant Shrivastava ◽  
Prakash Adwani
Keyword(s):  
Heat Flux ◽  
Critical Heat Flux ◽  
Base Fluid ◽  
Sol Gel ◽  
Copper Oxide Nanoparticles ◽  
Cuo Nanoparticles ◽  
Oxide Nanoparticles ◽  
Heater Surface

The main focus of the present work is to prepare the CuO nanoparticles by economical Sol-Gel method and further to prepare the CuO nanofluid with base fluid as deionised water. The size of nanoparticles is determined by Debye- Scherer formula and size of the particles is conformed 20.4054nm. Critical heat flux characteristics of nanofluid were investigated with different weight concentrations of CuO nanoparticles. The experimental work revealed an increase in critical heat flux value just about 57.26 percent. Surface roughness of heater surface is measured for all weight concentrations of nanofluid which shows increase in Ra value up to some extent is a cause to enhance CHF.

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