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Development of infrared spectroscopy techniques for environmental monitoring

Sandsten, Jonas LU (2000)
Abstract
Infrared spectroscopy techniques have long been utilized in identifying and quantifying species of interest to us. Many of the elementary molecules in the atmosphere interact with infrared radiation through their ability to absorb and emit energy in vibrational and rotational transitions. A large variety of methods for monitoring of molecules and aerosol particles by collecting samples or by using remote sensing methods are available. The objective of this thesis work was to develop infrared spectroscopic techniques to further enhance the amount of useful information obtained from gathering spectral data.



A new method for visualization and quantification of gas flows based on gas-correlation techniques was developed.... (More)
Infrared spectroscopy techniques have long been utilized in identifying and quantifying species of interest to us. Many of the elementary molecules in the atmosphere interact with infrared radiation through their ability to absorb and emit energy in vibrational and rotational transitions. A large variety of methods for monitoring of molecules and aerosol particles by collecting samples or by using remote sensing methods are available. The objective of this thesis work was to develop infrared spectroscopic techniques to further enhance the amount of useful information obtained from gathering spectral data.



A new method for visualization and quantification of gas flows based on gas-correlation techniques was developed. Real-time imaging of gas leaks and incomplete or erratic flare combustion of ethene was demonstrated. The method relies on the thermal background as a radiation source and the gas can be visualized in absorption or in emission depending on the temperature difference.



Diode laser spectroscopy was utilized to monitor three molecular species at the same time and over the same path. Two near-infrared diode lasers beams were combined in a periodically poled lithium niobate crystal and by difference-frequency generation a third beam was created, enabling simultaneous monitoring of oxygen, water vapor and methane.



Models of aerosol particle cross sections were used to simulate the diffraction pattern of light scattered by fibers, spherical particles and real particles, such as pollen, through a new aerosol particle sensing prototype. The instrument, using a coupled cavity diode laser, has been designed with a ray-tracing program and the final prototype was employed for single aerosol particle sizing and identification. (Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Professor Platt, Ulrich
organization
publishing date
type
Thesis
publication status
published
subject
keywords
environmental pollution measurements, infrared spectrometers, diffraction and scattering, absorption spectroscopy, remote sensing, ray tracing, image processing, Atomic and molecular physics, Atom- och molekylärfysik, Fysicumarkivet A:2000:Sandsten
pages
134 pages
publisher
Department of Physics, Lund University
defense location
Physics Department, Lecture Hall B
defense date
2000-09-22 10:15
external identifiers
  • Other:LUTFD2/(TFAF-1043)/1-72(2000)
ISBN
91-7874-055-X
language
English
LU publication?
yes
id
12d67d91-0813-43e8-b438-5ea8a346f4b3 (old id 40702)
date added to LUP
2007-10-01 09:38:24
date last changed
2016-09-19 08:45:09
@misc{12d67d91-0813-43e8-b438-5ea8a346f4b3,
  abstract     = {Infrared spectroscopy techniques have long been utilized in identifying and quantifying species of interest to us. Many of the elementary molecules in the atmosphere interact with infrared radiation through their ability to absorb and emit energy in vibrational and rotational transitions. A large variety of methods for monitoring of molecules and aerosol particles by collecting samples or by using remote sensing methods are available. The objective of this thesis work was to develop infrared spectroscopic techniques to further enhance the amount of useful information obtained from gathering spectral data.<br/><br>
<br/><br>
A new method for visualization and quantification of gas flows based on gas-correlation techniques was developed. Real-time imaging of gas leaks and incomplete or erratic flare combustion of ethene was demonstrated. The method relies on the thermal background as a radiation source and the gas can be visualized in absorption or in emission depending on the temperature difference.<br/><br>
<br/><br>
Diode laser spectroscopy was utilized to monitor three molecular species at the same time and over the same path. Two near-infrared diode lasers beams were combined in a periodically poled lithium niobate crystal and by difference-frequency generation a third beam was created, enabling simultaneous monitoring of oxygen, water vapor and methane.<br/><br>
<br/><br>
Models of aerosol particle cross sections were used to simulate the diffraction pattern of light scattered by fibers, spherical particles and real particles, such as pollen, through a new aerosol particle sensing prototype. The instrument, using a coupled cavity diode laser, has been designed with a ray-tracing program and the final prototype was employed for single aerosol particle sizing and identification.},
  author       = {Sandsten, Jonas},
  isbn         = {91-7874-055-X},
  keyword      = {environmental pollution measurements,infrared spectrometers,diffraction and scattering,absorption spectroscopy,remote sensing,ray tracing,image processing,Atomic and molecular physics,Atom- och molekylärfysik,Fysicumarkivet A:2000:Sandsten},
  language     = {eng},
  pages        = {134},
  publisher    = {ARRAY(0x78e76e8)},
  title        = {Development of infrared spectroscopy techniques for environmental monitoring},
  year         = {2000},
}