Thermal Emissivity and Solar Absorptivity of Aluminum Coated with Double Layers of Aluminum Oxide and Silicon Oxide

1971 ◽  
Vol 10 (6) ◽  
pp. 1296 ◽  
Author(s):  
G. Hass ◽  
J. B. Ramsey ◽  
J. B. Heaney ◽  
J. J. Triolo
Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 408
Author(s):  
Wen-Ching Hsieh ◽  
Fun-Cheng Jong ◽  
Wei-Ting Tseng

This research demonstrates that an indium tin oxide–silicon oxide–hafnium aluminum oxide‒silicon oxide–silicon device with enhanced UV transparency ITO gate (hereafter E-IOHAOS) can greatly increase the sensing response performance of a SONOS type ultraviolet radiation total dose (hereafter UV TD) sensor. Post annealing process is used to optimize UV optical transmission and electrical resistivity characterization in ITO film. Via nano-columns (NCols) crystalline transformation of ITO film, UV transparency of ITO film can be enhanced. UV radiation causes the threshold voltage VT of the E-IOHAOS device to increase, and the increase of the VT of E-IOHAOS device is also related to the UV TD. The experimental results show that under UV TD irradiation of 100 mW·s/cm2, ultraviolet light can change the threshold voltage VT of E-IOHAOS to 12.5 V. Moreover, the VT fading rate of ten-years retention on E-IOHAOS is below 10%. The VT change of E-IOHAOS is almost 1.25 times that of poly silicon–aluminum oxide–hafnium aluminum oxide–silicon oxide–silicon with poly silicon gate device (hereafter SAHAOS). The sensing response performance of an E-IOHAOS UV TD sensor is greatly improved by annealed ITO gate.


Author(s):  
Jorge Silva-Yumi ◽  
Telmo Moreno Romero ◽  
Gabriela Chango Lescano

Nanofluids constitute an alternative for the most efficient use of energy as they allow generating or improving thermal properties among others of traditional fluids, they are defined as so-called base fluids, such as: water, ethylene glycol, oils, etc., which contain nanoparticles in suspension , such as: aluminum oxide, silicon oxide, titanium oxide, metal nanoparticles, carbon nanotubes, graphene, carbides, etc. Nanofluids can be synthesized by two methods, the nanoparticles can be obtained separately and then the nanofluid is prepared or both nanoparticles and the nanofluid can be prepared simultaneously, an important factor to consider in obtaining nanofluids is their stability. Stability can be achieved by physical treatment or chemical treatment using surfactants. There are many studies about nanofluids, however, most are obtained with synthetic nanoparticles, leaving the use of natural nanoparticles as a field to be explored, as well as other surfactants to improve their stability. Keywords: nanofluids, hybrid nanofluids, nanoparticles, nano refrigerant. Resumen Los nanofluidos constituyen una alternativa para el uso más eficiente de energía pues permiten generar o mejorar las propiedades térmicas entre otras de los fluidos tradicionales, son definidos como fluidos denominados base, como: agua, etilenglicol, aceites, etc., que contienen nanopartículas en suspensión, como: óxido de aluminio, óxido de silicio, óxido de titanio, nanopartículas metálicas, nanotubos de carbono, grafeno, carburos, etc. Los nanofluidos se pueden sintetizar por dos métodos, se pueden obtener las nanopartículas por separado y luego preparar el nanofluido o se puede preparar simultáneamente las nanopartículas y el nanofluido, un factor importante a considerar en la obtención de nanofluidos es su estabilidad. La estabilidad se puede lograr mediante tratamiento físico o tratamiento químico mediante la utilización de surfactantes. Existen muchos estudios acerca de nanofluidos sin embargo, la mayoría se obtienen con nanopartículas sintéticas, quedando el uso de nanopartículas naturales como un campo por explorar al igual que otros surfactantes para mejorar su estabilidad. Palabras Clave: nanofluidos, nonofluidos híbridos, nanoparticulas, nanorefrigerantes.


2020 ◽  
Vol 51 (6) ◽  
pp. 430-436
Author(s):  
N. M. Varrik ◽  
A. M. Zimichek ◽  
A. V. Sumin ◽  
O. N. Samorodova

2020 ◽  
Vol 977 ◽  
pp. 250-255
Author(s):  
Wen Ching Hsieh ◽  
Wei Ting Tseng ◽  
Fuh Cheng Jong ◽  
Hao Tien Daniel Lee

The silicon-aluminum oxide-nitride-silicon oxide-silicon (hereafter SANOS) could be candidates for ultra violet total dose (hereafter UV TD) nonvolatile sensors. In the case of SANOS UV TD radiation sensors, the UV radiation induces a significant increase of threshold voltage VT. The changes of VT for SANOS after UV radiation have a correlation to the UV TD as well. In this paper, the performance for capacitor types of SANOS UV TD nonvolatile sensor were discussed in detailed. The SANOS capacitor device in this study has demonstrated the better feasibility for UV TD nonvolatile sensor application.


2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Amanda Sayure Kasuya de Oliveira ◽  
Adriana Perpetua Figueiredo Paulista ◽  
Ana Ellen Valentim de Alencar ◽  
Tiago Pinheiro Braga

Aluminum oxide and/or silicon oxide-based supports were synthesized by proteic sol-gel method. The characterization was performed through the analysis of TG, XRD, FTIR, SEM, and N2 physisorption. The XRD diffractograms showed an amorphous material profile. TG results indicate the total liberation of the organic and inorganic material in the calcination temperature used, occurring in different mass loss range. This piece of information was reaffirmed by the FTIR spectra, which presented characteristic bands of gelatin structure before calcinations which disappear in the spectrum of the solid after calcinations, indicating the loss of organic matter from gelatin after heat treatment. The spectra exhibited M-O stretching vibration at low wavenumbers after calcinations related to metal oxides. The acquired images by SEM suggest the obtaining of a highly porous material with very different characteristics depending on the composition of the support. The N2 isotherms indicate the presence of a micro/mesoporous oxide with interesting textural properties, particularly for the supports containing aluminum and silicon oxide. The ethanol dehydration results showed greater selectivity to diethyl ether compared to ethylene. From the reaction data, the following order of acid strength was obtained: 2Si-Al > Si-2Al > Si-Al > Al, which is related to the Si-Al ratio.


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