Ratiometric method for ozone absorption cross section measurement

Also available in printed version

Bibliographic Details
Main Author: Tay, Marcus Ching En
Other Authors: Mohd. Haniff Ibrahim, supervisor
Format: Doctoral thesis
Language:English
Published: Universiti Teknologi Malaysia 2025
Subjects:
Online Access:https://utmik.utm.my/handle/123456789/55973
Abstract Abstract here
_version_ 1854975114109517824
author Tay, Marcus Ching En
author2 Mohd. Haniff Ibrahim, supervisor
author_facet Mohd. Haniff Ibrahim, supervisor
Tay, Marcus Ching En
author_sort Tay, Marcus Ching En
description Also available in printed version
format Doctoral thesis
id utm-123456789-55973
institution Universiti Teknologi Malaysia
language English
publishDate 2025
publisher Universiti Teknologi Malaysia
record_format dspace
record_pdf Abstract
spelling utm-123456789-559732025-08-21T12:47:26Z Ratiometric method for ozone absorption cross section measurement Tay, Marcus Ching En Mohd. Haniff Ibrahim, supervisor Electrical engineering Also available in printed version Ultraviolet absorption spectroscopy has been practised for ozone concentration measurement because the method of measurement is fast and reliable. Ratiometric method corrects intensity drift of light source for improvement of measurement stability. However, ozone absorption cross section may not be determined via ratiometric method because of limitation of existing Beer–Lambert law. Absorption cross section defines strength of absorption, which is an important parameter for calculation of ozone concentration. Firstly, optical path length of gas cell that suits dynamic range of ozone monitor in this work (less than 1000 ppm) is determined. Based on spectralcalc.com simulation, gas cells of optical path lengths of 5 cm, 10 cm and 20 cm are optimized for concentration measurement from 494.1 ppm to 988.1 ppm, 247.0 ppm to 494.1 ppm and 123.5 ppm to 247.0 ppm respectively. Secondly, Beer–Lambert law deviation is observed when long gas cell of optical path length 10 cm is used to measure high ozone concentration from 357 ppm to 971 ppm. Typically, ozone is sampled using strong absorption wavelength for high sensitivity measurement. When strong absorption wavelengths cause saturation, linearity of measurement is preserved by sampling ozone using weak absorption wavelength 279.95 nm. Thirdly, temperature and pressure stability of ozone absorption cross section are verified using spectralcalc.com simulation. Finally, a novel equation is established based on Beer– Lambert law for measurement of ozone absorption cross section via ratiometric method. The equation is verified for ozone concentration measurement from 450 ppm to 989 ppm using short gas cell of optical path length 5 cm, sampling wavelength 260.99 nm and reference wavelength 377.05 nm. The equation is attractive to researchers in areas of absorption spectroscopy and optical gas sensor because ratiometric method is gaining popularity for high stability ozone concentration measurement fahmimoksen UTM 153 p. Thesis (Ph.D (Kejuruteraan Elektrik)) - Universiti Teknologi Malaysia, 2015 2025-03-17T04:08:03Z 2025-03-17T04:08:03Z 2015 Doctoral thesis https://utmik.utm.my/handle/123456789/55973 valet-20170213-094130 vital:95161 ENG Closed Access UTM Complete Unpublished application/pdf Universiti Teknologi Malaysia
spellingShingle Electrical engineering
Tay, Marcus Ching En
Ratiometric method for ozone absorption cross section measurement
thesis_level PhD
title Ratiometric method for ozone absorption cross section measurement
title_full Ratiometric method for ozone absorption cross section measurement
title_fullStr Ratiometric method for ozone absorption cross section measurement
title_full_unstemmed Ratiometric method for ozone absorption cross section measurement
title_short Ratiometric method for ozone absorption cross section measurement
title_sort ratiometric method for ozone absorption cross section measurement
topic Electrical engineering
url https://utmik.utm.my/handle/123456789/55973
work_keys_str_mv AT taymarcuschingen ratiometricmethodforozoneabsorptioncrosssectionmeasurement