EFFECT OF HIGH PRESSURES ON THE INFRARED AND RED ATMOSPHERIC ABSORPTION BAND SYSTEMS OF OXYGEN

1963 ◽  
Vol 41 (12) ◽  
pp. 1991-2002 ◽  
Author(s):  
C. W. Cho ◽  
E. J. Allin ◽  
H. L. Welsh
Keyword(s):  
Absorption Band ◽  
Power Series ◽  
Absorption Coefficient ◽  
Magnetic Dipole ◽  
Total Pressure ◽  
High Pressures ◽  
Linear Term ◽  
Quadratic Term ◽  
Atmospheric Absorption ◽  
Induced Absorption

Absorption intensities in the 0–0 and 1–0 bands of the infrared [Formula: see text] and the 0–0 band of the red [Formula: see text] band systems of oxygen were measured in the pure gas in the range 50 to 150 atm and in O2–N2, O2–A, and O2–He mixtures up to 3000 atm total pressure at 25 °C. The integrated absorption coefficient of each band is expressed as a power series in ρO2 and ρf, the Amagat densities of oxygen and the foreign gas, respectively. The coefficient of the linear term AρO2 is a measure of the intrinsic (magnetic dipole) absorption of the O2 molecule; it is much greater in the red than in the infrared system. The quadratic term, BρO22, gives the induced absorption in O2–O2 pairs; B is about ten times greater in the infrared than in the red system. These results explain intensity anomalies which have been observed in condensed oxygen. Induction effects in O2–N2 and O2–A pairs are much smaller than in O2–O2 pairs, and scarcely observable in O2–He pairs. The significance of these results is discussed.

The ν1 Band of Carbon Dioxide in Pressure-Induced Absorption. II. Density and Temperature Dependence of the Intensity; Critical Phenomena

1972 ◽  
Vol 50 (12) ◽  
pp. 1355-1362 ◽  
Author(s):  
L. Mannik ◽  
J. C. Stryland
Keyword(s):  
Carbon Dioxide ◽  
Absorption Coefficient ◽  
Density Range ◽  
Induced Absorption ◽  
Lennard Jones ◽  
Molecular Potential ◽  
Band Profile ◽  
Gaseous Carbon Dioxide ◽  
Interaction Term ◽  
Path Lengths

The ν1 band of gaseous carbon dioxide has been studied in pressure-induced absorption at temperatures of ~ 190, ~ 300, and ~ 470 K, over a density range from 0.5 to 300 amagat, and with path lengths from 0.007 to 56 m. The observed temperature variation of the binary absorption coefficient can be satisfactorily accounted for only by adding a quadrupole–quadrupole interaction term to the usual Lennard–Jones model for the inter-molecular potential. The band profile is in agreement with the theory of quadrupole-induced absorption. There is some increase in the intensity of the band near the critical point due to the divergence of the correlation length. A very marked increase in the intensity is possibly prevented by the "cancellation effect".

Abstract 13944: J Relationship of Body Mass Index of 22-year Cardiovascular Disease Mortality versus Body Mass Index

Circulation ◽  
2015 ◽  
Vol 132 (suppl_3) ◽  
Author(s):  
William J Kostis ◽  
Javier Cabrera ◽  
Fei Wang ◽  
Sara J Guterl ◽  
Dhammika Amaratunga ◽  
...  
Keyword(s):  
Risk Factors ◽  
Body Mass Index ◽  
Body Mass ◽  
Systolic Hypertension ◽  
Female Gender ◽  
The Elderly ◽  
Linear Term ◽  
Quadratic Term ◽  
All Cause Mortality ◽  
Cv Disease

Introduction: J relationships of body mass index (BMI) with mortality have been described. However, little data are available on long-term follow-up in controlled clinical trials with respect to cardiovascular (CV) and all cause mortality. Hypothesis: We tested whether there is a J shape relationship between BMI with CV and all cause mortality at 22 years in the Systolic Hypertension in the Elderly Program (SHEP). Methods: SHEP was a placebo controlled, randomized clinical trial of antihypertensive therapy in patients with isolated systolic hypertension aged 60 and older. The relationship between CV and all cause mortality with baseline BMI was examined in 4,211 SHEP participants. Results: In unadjusted analyses, a J relationship was observed for all-cause mortality (linear term p=0.0318, quadratic term p=0.3217 and tricubic term p=0.0046) and for CV mortality (linear term p=0.0962, quadratic term p=0.6866 and tricubic term p=0.0908, left figure). The lowest risk was at a BMI of 25.9 for all-cause and 25.5 for CV mortality. The J shaped relationship between BMI and mortality was attenuated after adjustment for age, gender, comorbidities (e.g. diabetes, heart failure) and risk factors for CV disease (e.g. smoking and dyslipidemia, right figure). Age and gender were significant predictors of both all- cause and CV mortality: age p<0.0001, female gender p=0.0063 for all-cause mortality and p<0.0001 for age and p=0.0004 for female gender for CV mortality. <br/Conclusions: This study indicates that both very low and very high BMI are markers of high risk. The J relationship between BMI and mortality is mediated by age, female gender, comorbidities and risk factors for CV disease.

Light-induced absorption and optical damage in Sc-, Mg-, and Zn-doped near-stoichiometric LiNbO3

2018 ◽  
Vol 27 (03) ◽  
pp. 1850030 ◽  
Author(s):  
Junsheng Li ◽  
Youwen Liu ◽  
Huijie Zhang ◽  
Liangzun Tang ◽  
Chongjun He
Keyword(s):  
Steady State ◽  
Lithium Niobate ◽  
Absorption Coefficient ◽  
Ultraviolet Light ◽  
Infrared Absorption ◽  
Doping Level ◽  
Doping Concentration ◽  
Weak Absorption ◽  
Induced Absorption ◽  
Infrared Absorption Spectra

By measuring the ultraviolet-light-induced absorption in Sc-, Mg- and Zn-doped near-stoichiometric lithium niobate (LiNbO[Formula: see text], we find that the steady-state ultraviolet-light-induced absorption coefficient changes with respect to the doping concentration. There is a strong ultraviolet-light-induced absorption when doping concentration is below its photorefractive threshold and a really weak absorption when the crystal is highly doped. We also use OH[Formula: see text] infrared absorption spectra and the transmitted light spot distortion method to verify the result. Thus, we can determine if the doping level in these doped near-stoichiometric LiNbO3 crystals is above or below their photorefractive threshold by measuring the ultraviolet-light-induced absorption.

Defect-induced absorption-band-edge values in β-FeSi2

1995 ◽  
Vol 52 (3) ◽  
pp. 1692-1697 ◽  
Author(s):  
C. H. Olk ◽  
S. M. Yalisove ◽  
G. L. Doll
Keyword(s):  
Absorption Band ◽  
Band Edge ◽  
Absorption Band Edge ◽  
Induced Absorption

scholarly journals Sun-induced leaf fluorescence retrieval in the O_2-B atmospheric absorption band

2008 ◽  
Vol 16 (10) ◽  
pp. 7014 ◽  
Author(s):  
Marina Mazzoni ◽  
Pierluigi Falorni ◽  
Samuele Del Bianco
Keyword(s):  
Absorption Band ◽  
Atmospheric Absorption
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