Examining the Diffuse Reflectance Spectra and the Radiation Stability for the Mixtures of BaSO4 Micropowders and SiO2 Nanopowders with Various Specific Surface Area

The paper is devoted to studying the effect of the specific surface area (SSA) of SiO2nanopowders (3 wt.%) added to BaSO4powders of a micron size on grain size distribution and diffuse reflectance spectra (ρλ) within the UV, visible, and near IR regions. Additionally, the authors have examined the spectra alteration (Δρλ) after irradiating with electrons (E=30 KeV). It has been established that mere mixing of the powders at a low concentration of nanoparticles leads to the post-irradiation decrease in the reflective power and to the subsequent increase in the reflectance coefficient stability.

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Effect of Preparation Parameters on the Microporous Structure of Ni/SiO2 Catalysts

MRS Proceedings ◽

10.1557/proc-431-379 ◽

1996 ◽

Vol 431 ◽

Author(s):

F. E. Castillon ◽

N. Bodganchikova ◽

S. Fuentes ◽

M. Avalos

Keyword(s):

Surface Area ◽

Silicic Acid ◽

Diffuse Reflectance ◽

Nickel Nitrate ◽

Reflectance Spectra ◽

Microporous Structure ◽

Hydrogenation Catalysts ◽

Diffuse Reflectance Spectra ◽

Group 2

AbstractIn this work we report the synthesis of Ni/SiO2 catalysts promoted by group 2 (IIA) cations (calcium and barium) which are currently used as hydrogenation catalysts. The effect of the preparation parameters aging, base agent, and type of cation, on the surface area of catalysts is evaluated. Catalysts were prepared by precipitation of the precursor silicic acid, along with nickel nitrate and calcium and barium carbonates, with NaOH, NH4OH and Na2CO3as precipitating agents. Catalysts were characterized by diffuse reflectance spectra (DRS) and by BETsurface area measurements. Results are discussed in terms of solgel chemistry (1).

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Improved Photocatalytic Activity of La3+-Doped Bi2O3

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.239-242.86 ◽

2011 ◽

Vol 239-242 ◽

pp. 86-89 ◽

Cited By ~ 5

Author(s):

Jun Zeng ◽

Jun Bo Zhong ◽

Jian Zhang Li ◽

Shao Hua Wang ◽

Wei Hu

Keyword(s):

Photocatalytic Activity ◽

Binding Energy ◽

Specific Surface ◽

Pore Size ◽

Surface Area ◽

Specific Surface Area ◽

Pore Volume ◽

Diffuse Reflectance ◽

Bet Surface Area

In this paper, Bi2O3 doped with different amount of La3+ was prepared. The prepared photocatalysts were characterized by BET, XRD, UV-VIS diffuse reflectance and XPS. The results show that 3%La3+-Bi2O3 prepared has the highest BET surface area, pore volume, the smallest pore size. 3%La3+-Bi2O3 exhibits the best photocatalytic activity. The results of further experiments show that the specific surface area, UV-Vis diffuse reflectance and the binding energy all play an important role in promotion of photocatalytic activity of Bi2O3 nanostructure.

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The effects of heating on BaSO4 powders' diffuse reflectance spectra and radiation stability

Dyes and Pigments ◽

10.1016/j.dyepig.2018.12.022 ◽

2019 ◽

Vol 163 ◽

pp. 420-424 ◽

Cited By ~ 5

Author(s):

M.M. Mikhailov ◽

S.A. Yuryev ◽

A.N. Lapin ◽

A.A. Lovitskiy

Keyword(s):

Diffuse Reflectance ◽

Radiation Stability ◽

Reflectance Spectra ◽

Diffuse Reflectance Spectra

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SOME ADSORPTION PHENOMENA OF NITROANILINES ON ALKALINE EARTH COMPOUNDS

Canadian Journal of Chemistry ◽

10.1139/v66-446 ◽

1966 ◽

Vol 44 (24) ◽

pp. 3051-3056 ◽

Cited By ~ 1

Author(s):

R. W. Frei ◽

H. Zeitlin ◽

G. Fujie

Keyword(s):

Surface Area ◽

Alkaline Earth ◽

Diffuse Reflectance ◽

Visible Region ◽

Reflectance Spectroscopy ◽

Reflectance Spectra ◽

Electronic Polarization ◽

Diffuse Reflectance Spectra ◽

Polarization Theory ◽

Adsorption Phenomena

The spectral behavior of o- and p-nitroanaline adsorbed on various alkaline earth compounds has been studied by reflectance spectroscopy. Regular bathochromic shifts in the diffuse reflectance spectra have been observed for the absorption maxima in the visible region in order of increasing size of the adsorbent cation. Progressive removal of coadsorbed moisture which competes for active adsorbent sites resulted in an enhancement of the bathochromic shifts. The intensity of the absorption maxima as measured by peak heights was found to be dependent upon the size of both cations and anions of the adsorbents. Interpretation of observed phenomena was advanced in terms of electronic polarization theory and varying surface area of the adsorbents.

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