Air plasma spraying (APS) was used to produce high emissivity coatings with a NiCr204 spinel structure. The relationship between the emissivity and the crystal structure was investigated. X-ray diffraction (XRD) a...
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Air plasma spraying (APS) was used to produce high emissivity coatings with a NiCr204 spinel structure. The relationship between the emissivity and the crystal structure was investigated. X-ray diffraction (XRD) analyses show that NiCr204 spinel has been fabri- cated with the space group Fd3m. Scanning electron microscope (SEM) photographs show that the coating consists of a laminated structure with homogeneous grains and high porosity because of the unique feature of plasma spraying. The emissivity measurement and Fourier transformation infrared radiation (FT-IR) spectra show that NiCr204 has a high emissivity of about 0.91 because of its special spinel structure APS is a suitable method to produce high emissivity coatings.
Crystalline microporous zeolites with pore sizes typically at 0.4-1.5 nra are one of the most useful catalysts in industrial processes such as oil refining and organic synthesis owing to their strong catalytic perform...
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Crystalline microporous zeolites with pore sizes typically at 0.4-1.5 nra are one of the most useful catalysts in industrial processes such as oil refining and organic synthesis owing to their strong catalytic performance,high thermal and hydrothermal stabilities,and well-defined micropores with excellent shape-selectivity in ***,one disadvantage of these zeolitic catalysts is that their pores are too small to be accessed by bulky reactants hindering their use in the fine chemical and petroleum processing industries. To overcome
Introduction Cellulose is an abundant and renewable *** is considered as an ideal feedstock for producing advanced biofuels which have similar properties to petroleum-based fuels and can 'drop in' to the exist...
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Introduction Cellulose is an abundant and renewable *** is considered as an ideal feedstock for producing advanced biofuels which have similar properties to petroleum-based fuels and can 'drop in' to the existing transportation infrastructure.
Crystal structure, piezoelectric, and dielectric properties were investigated on the (1-x)Pb(Zr0.54Ti0.46)O3-xKNbO3 system. The piezoelectric properties have been significantly improved by substituting a small amount ...
Crystal structure, piezoelectric, and dielectric properties were investigated on the (1-x)Pb(Zr0.54Ti0.46)O3-xKNbO3 system. The piezoelectric properties have been significantly improved by substituting a small amount of KNbO3. In the morphotropic phase boundary (x=0.015), the compound not only shows enhanced piezoelectric coefficient d33=450 pC/N, which is two times larger than that of unmodified Pb(Zr,Ti)O3 (d33=223 pC/N), but also the Curie temperature (TC=~380 °C) is still well maintained at a high level. This phenomenon challenges our general knowledge that in piezoelectric materials the Curie temperature and piezoelectric properties are mutually contradictory. It should be noted that a giant total strain as high as 0.73% is also observed. The high thermal depoling temperature more than 300 °C combined with the excellent piezoelectric properties suggest it as a potential candidate for high temperature actuators and sensors applications.
Monolayer graphene was deposited on a Si wafer substrate decorated with SiO2 nanoparticles (NPs) and then exposed to aryl radicals that were generated in situ from their diazonium precursors. Using micro-Raman mapping...
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An ultra-fast densification method based on high heating rate from the combustion reaction for producing carbon nanotubes (CNTs) reinforced alumina ceramics is reported. The heat generated by combustion reaction is ...
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An ultra-fast densification method based on high heating rate from the combustion reaction for producing carbon nanotubes (CNTs) reinforced alumina ceramics is reported. The heat generated by combustion reaction is adopted to act as a high temperature source to the sample, which results in a heating rate of 1660℃/min of the sample. Then a great mechanical pressure is applied to the sample when the sample gets the expected temperature. The densification process is finished in several minutes. The results indicate that the densification method is beneficial to protect the CNTs from destruction and creates good interracial combination between the nanotubes and the matrix. With the addition of 1 wt% CNTs, the fracture toughness of the ceramics prepared increases about 50%.
Ordered rutile TiO2 nanorods grown on transparent electro-conductive F-doped SnO2-coated (FTO) glass substrates were prepared by a simple hydrothermal method using tetrabutyl titanate as the precursor and then calcine...
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Sol-gel synthesis of intrinsic (i-ZnO) and aluminum-doped zinc oxide (Al:ZnO) thin films was carried out via spin coating process using 0.2 M Zn 2 + precursor salt, monoethanolamine to Zn2 + ratio of 0.75, and 1 and 2...
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A carbonization method is reported to improve the thermal conductivity of carbon nanotube (CNT) arrays. After being impregnated with phenolic resins, CNT arrays were carbonized at a temperature up to 1400°C. As a...
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A carbonization method is reported to improve the thermal conductivity of carbon nanotube (CNT) arrays. After being impregnated with phenolic resins, CNT arrays were carbonized at a temperature up to 1400°C. As a result, pyrolytic carbon was formed and connected non-neighboring CNTs. The pyrolysis improved the room temperature conductivity from below 2 W/m·K up to 11.8 and 14.6 W/m·K with carbonization at 800°C and 1400°C, respectively. Besides the light mass density of 1.1 g/cm3, the C/C composites demonstrated high thermal stability and a higher conductivity up to 21.4 W/m·K when working at 500°C.
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