Near IR reflectance characteristics of PMMA/ZnO nanocomposites for solar thermal control interface films

AbstractThe mineral conichalcite from the western part of Bagdad mine, Bagdad, Eureka District, Yavapai County, Arizona, USA has been characterized by electronic, near-infrared (NIR), Raman and infrared (IR) spectroscopy. Scanning electron microscopy (SEM) images show that the mineral consists of bundles of fibres. Calculations based on the results of the energy dispersive X-ray analyses on a stoichiometric basis show the substitution of arsenate by 12 wt.% of phosphate in the mineral. Raman and IR bands are assigned in terms of the fundamental modes of AsO43− and PO43− molecules and are related to the mineral structure. Near-IR reflectance spectroscopy shows the presence of adsorbed water and hydroxyl units in the mineral. The Cu(II) coordination polyhedron in conichalcite can have at best pseudo-tetragonal geometry. The crystal field and tetragonal field parameters of the Cu(II) complex were calculated and found to agree well with the values reported for known tetragonal distortion octahedral complexes.

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On the Radiation Stability of BaSO4 Pigment Modified with SiO2 Nanoparticles and Applied for Spacecraft Thermal Control Coatings

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.386.277 ◽

2018 ◽

Vol 386 ◽

pp. 277-282 ◽

Cited By ~ 1

Author(s):

Mikhail M. Mikhailov ◽

Vitaly V. Neshchimenko ◽

Semyon A. Yuryev ◽

Anatoly V. Grigorevsky ◽

Alexey A. Lovitskiy ◽

...

Keyword(s):

Thermal Control ◽

Radiation Stability ◽

Maximum Effect ◽

Nanoparticle Concentration ◽

Absorption Bands ◽

Near Ir ◽

Uv Visible ◽

Thermal Control Coatings ◽

Spacecraft Thermal Control ◽

High Temperature Modification

The authors investigated the effect of a high-temperature modification with SiO2 nanoparticles on the optical properties and radiation stability of BaSO4 powders. The modification leads to insignificant alteration in the reflecting capacity within the UV, visible, and near-IR spectral regions. Appending SiO2 nanoparticles with a concentration of up to 10 wt.% results in the increasing radiation stability of BaSO4 powders. The maximum effect was obtained due to the decreasing intensity of the absorption bands at 270-280, 375-395, 440-460, 500-600, 700, and 950 nm at a nanoparticle concentration of 3 wt.%.

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Empirical relationship between near-IR reflectance of melting seasonal snow and environmental temperature in a Himalayan basin

Remote Sensing of Environment ◽

10.1016/j.rse.2006.09.011 ◽

2007 ◽

Vol 107 (3) ◽

pp. 402-413 ◽

Cited By ~ 11

Author(s):

R GUPTA ◽

A GHOSH ◽

U HARITASHYA

Keyword(s):

Environmental Temperature ◽

Empirical Relationship ◽

Seasonal Snow ◽

Near Ir ◽

Ir Reflectance

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Near-IR Reflectance Spectroscopy for the Determination of Motor Oil Contamination in Sandy Loam

Applied Spectroscopy ◽

10.1366/0003702963906221 ◽

1996 ◽

Vol 50 (3) ◽

pp. 334-338 ◽

Cited By ~ 26

Author(s):

Brian R. Stallard ◽

Manuel J. Garcia ◽

Sumanth Kaushik

Keyword(s):

Organic Contaminants ◽

Sandy Loam ◽

Sampling Error ◽

Reflectance Spectroscopy ◽

Oil Contamination ◽

Motor Oil ◽

Near Ir ◽

Ir Reflectance ◽

The One

We have investigated the application of near-IR reflectance spectroscopy to the determination of motor oil contamination in sandy loam. Although the present work is concerned with a specific case of contamination, we discuss the possibility of applying the method to other organic contaminants and other types of soil. The spectral region considered was 1600–1900 nm, which contains the first overtone of the CH stretch. Using a commercial Fourier transform spectrometer together with cross-validated partial least-squares data analysis, the one-sigma precision for the determination of motor oil in sandy loam was 0.17 wt % (0.13 to 0.26 wt % at the 95% confidence level). The largest contribution to the precision of the determination was sampling error, or inhomogeneity in each sample. Given the precision limit imposed by the sampling error, we found that the performance of the spectrometer could be lowered without affecting the overall precision. In a modeling exercise, adequate performance was obtained with a spectrometer having only seven spectral channels with a spectral resolution of 10 nm and a spectral noise level of 10−3 absorbance units. A design for an inexpensive miniature instrument is presented.

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