Spectral Extinction Coefficient Test of the Photoelectric Jamming Aerosol

2015 ◽  
Author(s):  
T. Zhang ◽  
X.D. Dai ◽  
L. Chen ◽  
C.S. Chen ◽  
H.F. Liu ◽  
...  
Keyword(s):  
Extinction Coefficient ◽  
Spectral Extinction Coefficient

Thermal Radiation in Silica Aerogel and its Composite Insulation Materials

2011 ◽  
Author(s):  
Gaosheng Wei ◽  
Yusong Liu ◽  
Xinxin Zhang ◽  
Xiaoze Du
Keyword(s):  
Thermal Radiation ◽  
Extinction Coefficient ◽  
Silica Aerogel ◽  
Extinction Coefficients ◽  
Ceramic Fibre ◽  
Insulation Materials ◽  
Hot Strip ◽  
Aerogel Composite ◽  
Infrared Spectrometer ◽  
Spectral Extinction Coefficient

This paper engages in experimental measurements on thermal radiative transfer in silica aerogel and its composite insulation materials (xonotlite-aerogel composite and ceramic fibre-aerogel composite). The samples of silica aerogel, xonotlite-type calcium silicate, and ceramic fibre insulation materials are all considered as a semi-transparent medium capable of absorbing, emitting and scattering thermal radiation. The spectral transmittances are then measured at different infrared wavelengths ranging from 2.5 to 25μm with a Fourier transform infrared spectrometer (FTIR), and subsequently used to determine the specific spectral extinction coefficient and the specific Rossland mean extinction coefficient of the sample. The radiative conductivities deduced from the overall thermal conductivities measured with the transient hot-strip (THS) method are compared with the predictions from the diffusion approximation by using the measured spectral extinction coefficient. The results show that the spectral extinction coefficients of the samples are strongly dependent on the wavelength, particularly in the short wavelength regime (<10μm). The total Rossland mean extinction coefficients of the samples are all decreasing with the temperature increasing. The radiative conductivities are found almost proportional to the cubic temperature, and decreases as the sample density increases.

Light Extinction by Fire Smokes

1997 ◽  
Vol 15 (3) ◽  
pp. 180-202 ◽  
Author(s):  
Paolo Coppa ◽  
Antonio La Malfa
Keyword(s):  
Visible Light ◽  
Optical Density ◽  
Extinction Coefficient ◽  
Research Center ◽  
Light Extinction ◽  
Test Room ◽  
Spectral Extinction Coefficient

Visibility of escape routes is most important to guarantee the safety of people indoors during fires. In the case of a fire, visibility is strongly in fluenced by the smoke present in the room. In the present work, the extinction co efficient of the visible light has been experimentally measured in the presence of the smoke produced by four different test fires, named TF2, TF3, TF4, and TF5. Tests have been carried out in a specially suited test room in the Italian Fire De partment Research Center, provided with instruments to measure the optical density of smoke and the spectral extinction coefficient.

Horizon line scanning telephotometry

1982 ◽  
Vol 60 (11) ◽  
pp. 1641-1647
Author(s):  
A. W. Harrison ◽  
J. Lant
Keyword(s):  
Experimental Study ◽  
Lower Limit ◽  
Extinction Coefficient ◽  
Earth Surface ◽  
The Earth ◽  
Horizon Line ◽  
Line Scanning ◽  
Spectral Extinction Coefficient

The horizon line softening method of determining the atmospheric spectral extinction coefficient σ(λ) is analyzed in detail indicating an inherent lower limit σ0(λ) on the range of σ(λ) which can be measured by this technique. As the observation height h above the earth surface increases, σ0(λ) decreases. A comparative experimental study of horizon line scanning telephotometry and contrast telephotometry is described, the results of which show the former technique to be useful under certain observing conditions.

Synthesis and Characterization of ROSA Dye - A Rhodamine B-type Fluorophore, Suitable for Bioconjugation and Fluorescence Studies in Live Cells

2019 ◽  
Vol 26 (10) ◽  
pp. 758-767
Author(s):  
Vicente Rubio ◽  
Vijaya Iragavarapu ◽  
Maciej J. Stawikowski
Keyword(s):  
Quantum Yield ◽  
Cancer Cells ◽  
Fluorescent Probe ◽  
Extinction Coefficient ◽  
Rhodamine B ◽  
Solid Phase ◽  
Total Yield ◽  
Molar Extinction Coefficient ◽  
Αvβ3 Integrin ◽  
Αvβ3 Integrins

Background: Herein we report the multigram-scale synthesis, characterization and application of a rhodamine B-based fluorophore (ROSA) suitable for fluorescent studies in biological applications. This fluorophore is devoid of rhodamine spirolactone formation and furthermore characterized by a high molar extinction coefficient (ϵ=87250 ± 1630 M-1cm-1) and quantum yield (φ) of 0.589 ± 0.070 in water. Reported here is also the application of ROSA towards synthesis of a ROSA-PEG-GRGDS-NH2 fluorescent probe suitable for live cell imaging of αvβ3 integrins for in vitro assays. Objective: The main objective of this study is to efficiently prepare rhodamine B derivative, devoid of spirolactone formation that would be suitable for bioconjugation and subsequent bioimaging. Methods: Rhodamine B was transformed into rhodamine B succinimide ester (RhoB-OSu) using N-hydroxysuccinimide. RhoB-OSu was further coupled to sarcosine to obtain rhodamine Bsarcosine dye (ROSA) in good yield. The ROSA dye was then coupled to a αvβ3 integrin binding sequence using standard solid-phase conditions. Resulting ROSA-PEG-GRGDS-NH2 probe was used to image integrins on cancer cells. Results: The rhodamine B-sarcosine dye (ROSA) was obtained in multigram scale in good total yield of 47%. Unlike rhodamine B, the ROSA dye does not undergo pH-dependent spirolactone/spirolactam formation as compared with rhodamine B-glycine. It is also characterized by excellent quantum yield (φ) of 0.589 ± 0.070 in water and high molar extinction coefficient of 87250 ± 1630 M-1cm-1. ROSA coupling to the RGD-like peptide was proved to be efficient and straightforward. Imaging using standard filters on multimode plate reader and confocal microscope was performed. The αvβ3 integrins present on the surface of live WM-266-4 (melanoma) and MCF- 7 (breast cancer) cells were successfully imaged. Conclusion: We successfully derivatized rhodamine B to create an inexpensive, stable and convenient to use fluorescent probe. The obtained derivative has excellent photochemical properties and it is suitable for bioconjugation and many imaging applications.

Thermal conductivity and extinction coefficient of opacified expanded perlite for vacuum super insulation up to 1073 K

2021 ◽  
Vol 163 ◽  
pp. 106813
Author(s):  
Matthias Rottmann ◽  
Thomas Beikircher ◽  
Hans-Peter Ebert ◽  
Frank Hemberger ◽  
Jochen Manara
Keyword(s):  
Thermal Conductivity ◽  
Extinction Coefficient ◽  
Expanded Perlite
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