Author: C. J. Fisher
Publisher:
ISBN:
Category :
Languages : en
Pages : 32
Book Description
The analytic basis of an optical absorption technique suitable for a single line-of-sight determination of average gaseous species number densities in the presence of concentration, pressure and temperature gradients, and particulate loading is presented and applied to carbon monoxide (CO). Applying the technique involves using the power of very high-resolution infrared (IR) spectroscopy, now made available by tunable diode lasers. The method requires the construction of functions of molecular line strengths that are nearly temperature independent. A method of constructing these functions is described and applied to the case of CO. Possible applications to practical combustion systems are also outlined. (Author).
Temperature-Compensated High-Resolution Infrared Absorption Spectroscopy: Application to Carbon Monoxide
Author: C. J. Fisher
Publisher:
ISBN:
Category :
Languages : en
Pages : 32
Book Description
The analytic basis of an optical absorption technique suitable for a single line-of-sight determination of average gaseous species number densities in the presence of concentration, pressure and temperature gradients, and particulate loading is presented and applied to carbon monoxide (CO). Applying the technique involves using the power of very high-resolution infrared (IR) spectroscopy, now made available by tunable diode lasers. The method requires the construction of functions of molecular line strengths that are nearly temperature independent. A method of constructing these functions is described and applied to the case of CO. Possible applications to practical combustion systems are also outlined. (Author).
Publisher:
ISBN:
Category :
Languages : en
Pages : 32
Book Description
The analytic basis of an optical absorption technique suitable for a single line-of-sight determination of average gaseous species number densities in the presence of concentration, pressure and temperature gradients, and particulate loading is presented and applied to carbon monoxide (CO). Applying the technique involves using the power of very high-resolution infrared (IR) spectroscopy, now made available by tunable diode lasers. The method requires the construction of functions of molecular line strengths that are nearly temperature independent. A method of constructing these functions is described and applied to the case of CO. Possible applications to practical combustion systems are also outlined. (Author).
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 480
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 480
Book Description
High Resolution Infrared Spectroscopy of Carbon Dioxide and Nitrous Oxide at Elevated Temperatures
Author: Mark P. Esplin
Publisher:
ISBN:
Category : Atmospheric carbon dioxide
Languages : en
Pages : 72
Book Description
Although both Carbon Dioxide and Nitrous Oxide are minor constituents of the terrestrial atmosphere, they play leading roles in several current atmospheric problems. Both CO2 and N2O are greenhouse gases, and while it is known that the atmospheric concentrations of both gases is increasing, the impact of these trends on global temperature is not yet adequately understood. In addition to being a greenhouse gas, N2O plays an indirect part in ozone chemistry. Heating a molecule makes possible the observations of molecular transitions originating from highly excited rotation-vibration states. Heating a molecule makes possible the observations of molecular transitions originating from highly excited rotation-vibration states. These observations can then be used to characterize the shape of the molecular potential function at increasing distances from the minimum of the potential function. The infrared spectra of linear molecules like CO2 and N2O are composed of vibration bands made up of a number of nearly equally spaced rotation lines. A Fourier Spectrometer is ideally suited to the study of high temperature gases since it meets both of these needs by providing high resolution over a wide spectral region.
Publisher:
ISBN:
Category : Atmospheric carbon dioxide
Languages : en
Pages : 72
Book Description
Although both Carbon Dioxide and Nitrous Oxide are minor constituents of the terrestrial atmosphere, they play leading roles in several current atmospheric problems. Both CO2 and N2O are greenhouse gases, and while it is known that the atmospheric concentrations of both gases is increasing, the impact of these trends on global temperature is not yet adequately understood. In addition to being a greenhouse gas, N2O plays an indirect part in ozone chemistry. Heating a molecule makes possible the observations of molecular transitions originating from highly excited rotation-vibration states. Heating a molecule makes possible the observations of molecular transitions originating from highly excited rotation-vibration states. These observations can then be used to characterize the shape of the molecular potential function at increasing distances from the minimum of the potential function. The infrared spectra of linear molecules like CO2 and N2O are composed of vibration bands made up of a number of nearly equally spaced rotation lines. A Fourier Spectrometer is ideally suited to the study of high temperature gases since it meets both of these needs by providing high resolution over a wide spectral region.
Energy Research Abstracts
Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 900
Book Description
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 900
Book Description
Fossil Energy Update
Author:
Publisher:
ISBN:
Category : Fossil fuels
Languages : en
Pages : 936
Book Description
Publisher:
ISBN:
Category : Fossil fuels
Languages : en
Pages : 936
Book Description
Technical Abstract Bulletin
Author:
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 230
Book Description
Publisher:
ISBN:
Category : Science
Languages : en
Pages : 230
Book Description
Infrared Absorption Spectroscopy of Carbon Monoxide on Nickel Films
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Sensitive vibrational spectra of carbon monoxide molecules adsorbed on evaporated nickel films have been measured by attaching a thermometer to the sample, cooling the assembly to liquid helium temperatures, and recording the temperature changes which occur when infrared radiation is absorbed. The measurements are made in an ultrahigh vacuum chamber in which the sample surface can be cleaned, heated, exposed to gas molecules and cooled to 1.6 K for the infrared measurements. The spectra of chemisorbed CO molecules are interpreted in terms of the linear and bridge adsorption sites on the nickel surface, and they show how the distribution of molecules among these sites changes when the CO coverage increases and intermolecular forces become important. The spectra of physically adsorbed molecules in both monolayer and multilayer films are also reported. Absorptions as small as five parts in 105 of the incident radiation can presently be detected in spectra covering broad bands of infrared frequencies with a resolution of 2 cm−1. This high sensitivity is attributable to the low noise and reduced background signal of the thermal detection scheme, to the stability of the rapid scan Fourier transform infrared spectrometer, and to the automated computerized data acquisition electronics. Better performance is expected in future experiments on single crystal samples as well as evaporated films. This will make it possible to study molecules with weaker absorptions than CO and to look for evidence of chemical reactions between different adsorbed molecules.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Sensitive vibrational spectra of carbon monoxide molecules adsorbed on evaporated nickel films have been measured by attaching a thermometer to the sample, cooling the assembly to liquid helium temperatures, and recording the temperature changes which occur when infrared radiation is absorbed. The measurements are made in an ultrahigh vacuum chamber in which the sample surface can be cleaned, heated, exposed to gas molecules and cooled to 1.6 K for the infrared measurements. The spectra of chemisorbed CO molecules are interpreted in terms of the linear and bridge adsorption sites on the nickel surface, and they show how the distribution of molecules among these sites changes when the CO coverage increases and intermolecular forces become important. The spectra of physically adsorbed molecules in both monolayer and multilayer films are also reported. Absorptions as small as five parts in 105 of the incident radiation can presently be detected in spectra covering broad bands of infrared frequencies with a resolution of 2 cm−1. This high sensitivity is attributable to the low noise and reduced background signal of the thermal detection scheme, to the stability of the rapid scan Fourier transform infrared spectrometer, and to the automated computerized data acquisition electronics. Better performance is expected in future experiments on single crystal samples as well as evaporated films. This will make it possible to study molecules with weaker absorptions than CO and to look for evidence of chemical reactions between different adsorbed molecules.
Publications
Author: United States. National Bureau of Standards
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 788
Book Description
Publisher:
ISBN:
Category : Government publications
Languages : en
Pages : 788
Book Description
Publications of the National Bureau of Standards
Author: United States. National Bureau of Standards
Publisher:
ISBN:
Category : Washington (D.C.)
Languages : en
Pages : 234
Book Description
Publisher:
ISBN:
Category : Washington (D.C.)
Languages : en
Pages : 234
Book Description
Publications of the National Bureau of Standards ... Catalog
Author: United States. National Bureau of Standards
Publisher:
ISBN:
Category :
Languages : en
Pages : 228
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 228
Book Description