Effect of contour asymmetry on the intensity and the half-width determined by integral absorption measurements

1972 ◽  
Vol 16 (5) ◽  
pp. 642-645
Author(s):  
M. R. Cherkasov
Keyword(s):  
Half Width ◽  
Integral Absorption ◽  
Absorption Measurements

Characterization of Microcrystalline Transition from Amorphous Silicon as a Function of Hydrogen Dilution and Substrate Temperature of Hot-wire CVD

2002 ◽  
Vol 715 ◽  
Author(s):  
Keda Wang ◽  
Haoyue Zhang ◽  
Jian Zhang ◽  
Jessica M. Owens ◽  
Jennifer Weinberg-Wolf ◽  
...  
Keyword(s):  
Substrate Temperature ◽  
Sudden Change ◽  
Chemical Vapor ◽  
Threshold Value ◽  
Ir Absorption ◽  
Sudden Increase ◽  
Hot Wire ◽  
Hydrogen Dilution ◽  
Integral Absorption ◽  
Two Peaks

Abstracta-Si:H films were prepared by hot wire chemical vapor deposition. One group was deposited at a substrate temperature of Ts=250°C with varied hydrogen-dilution ratio, 0<R<10; the other group was deposited with fixed R=3 but a varied Ts from 150 to 550°C. IR, Raman and PL spectra were studied. The Raman results indicate that there is a threshold value for the microstructure transition from a- to μc-Si. The threshold is found to be R ≈ 2 at Ts = 250°C and Ts ≈ 200°C at R=3. The IR absorption of Si-H at 640 cm-1 was used to calculate the hydrogen content, CH. CH decreased monotonically when either R or Ts increased. The Si-H stretching mode contains two peaks at 2000 and 2090 cm-1. The ratio of the integral absorption peaks I2090/(I2090+I2090) showed a sudden increase at the threshold of microcrystallinity. At the same threshold, the PL features also indicate a sudden change from a- to μc-Si., i.e. the low energy PL band becomes dominant and the PL total intensity decreases. We attribute the above IR and PL changes to the contribution of microcrystallinity, especially the c-Si gain-boundaries.

High-Bandwidth Laser-Absorption Measurements of Temperature, Pressure, CO, and H2O in the Annulus of a Rotating Detonation Rocket Engine

2021 ◽  
Author(s):  
Garrett C. Mathews ◽  
Matthew Blaisdell ◽  
Aaron I. Lemcherfi ◽  
Carson D. Slabaugh ◽  
Christopher S. Goldenstein
Keyword(s):  
Rocket Engine ◽  
Laser Absorption ◽  
High Bandwidth ◽  
Rotating Detonation ◽  
Absorption Measurements

Solid Parahydrogen Thickness Revisited

2019 ◽  
Vol 73 (12) ◽  
pp. 1403-1408 ◽  
Author(s):  
Mario E. Fajardo
Keyword(s):  
Systematic Error ◽  
Absorption Spectroscopy ◽  
Ir Absorption ◽  
Spectroscopy Data ◽  
Previous Approach ◽  
Polarization Effects ◽  
Peak Intensity ◽  
Absorption Measurements

We report updated infrared (IR) absorption measurements on vapor-deposited cryogenic parahydrogen (pH2) solids that indicate a ≈10% systematic error in our previous approach for determining a pH2 solid's thickness (S. Tam and M.E. Fajardo. Appl. Spectrosc. 2001. 55(12): 1634-1644). We provide corrected values for the integrated absorption intensities of the Q1(0)+S0(0) and S1(0)+S0(0) bands calculated over the 4495–4520 cm−1 and 4825–4855 cm−1 regions, respectively. New polarized IR absorption spectroscopy data demonstrate the insensitivity to polarization effects of the peak intensity of the QR(0) phonon sideband near 4228 cm−1. This feature provides an even quicker way for determining the thickness of a pH2 solid than via the integrated absorptions.

Development of a new methodology for the retrieval of in-situ stratospheric trace gases concentration from airborne limb-absorption measurements

2002 ◽  
Author(s):  
Andrea Petritoli ◽  
Giorgio Giovanelli ◽  
Fabrizio Ravegnani ◽  
Daniele Bortoli ◽  
Ivan K. Kostadinov ◽  
...  
Keyword(s):  
Trace Gases ◽  
Stratospheric Trace Gases ◽  
Absorption Measurements

Toxicity and recalcitrant compound removal from bleaching pulp plant effluents by an integrated system: anaerobic packed-bed bioreactor and ozone

2010 ◽  
Vol 61 (1) ◽  
pp. 199-205 ◽  
Author(s):  
T. R. Chaparro ◽  
C. M. Botta ◽  
E. C. Pires
Keyword(s):  
Pulp Mill ◽  
Packed Bed ◽  
Ultraviolet Absorption ◽  
Integrated System ◽  
Packed Bed Bioreactor ◽  
Cellulose Pulp ◽  
Adsorbable Organic Halides ◽  
Organic Halides ◽  
Before And After ◽  
Absorption Measurements

Effluents originated in cellulose pulp manufacturing processes are usually toxic and recalcitrant, specially the bleaching effluents, which exhibit high contents of aromatic compounds (e.g. residual lignin derivates). Although biological processes are normally used, their efficiency for the removal of toxic lignin derivates is low. The toxicity and recalcitrance of a bleached Kraft pulp mill were assessed through bioassays and ultraviolet absorption measurements, i.e. acid soluble lignin (ASL), UV280, and specific ultraviolet absorption (SUVA), before and after treatment by an integrated system comprised of an anaerobic packed-bed bioreactor and oxidation step with ozone. Furthermore, adsorbable organic halides (AOX) were measured. The results demonstrated not only that the toxic recalcitrant compounds can be removed successfully using integrated system, but also the ultraviolet absorption measurements can be an interesting control-parameter in a wastewater treatment.

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