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All Journal International Journal of Advances in Applied Sciences Indonesian Journal of Electrical Engineering and Computer Science
Michael David
Federal University of Technology
Earth & Planetary Sciences Environmental Science Materials Science & Nanotechnology Mathematics Physics

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The concurrent upshot of optical path-length and pressure on O3 absorption cross-section in relation to green communication Michael David; Patrick Enenche; Caroline O. Alenoghena; Mohd Haniff Ibrahim; Sevia M. Idrus; Tay Ching En Marcus
International Journal of Advances in Applied Sciences Vol 11, No 2: June 2022
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (872.067 KB) | DOI: 10.11591/ijaas.v11.i2.pp97-106

Abstract

Ozone gas is a greenhouse gas. Accurate measurement of its concentration is dependent on the right value of the ozone gas absorption cross-section. In the literature, discrepancies and inconsistencies have been however linked with ozone gas absorption cross-section. In the literature, information on the pressure effect on pressures less than 100 mbar and greater than 100 but less than 1000 mbar is not available for the visible spectrum. Thus, creating an information gap that this manuscript is intended to fill up. This is the problem that has been addressed in this present work. The method of simulation with SpectralCalc is the method adopted for the present work. HITRAN 2012 simulator, available on spectralcalc.com, was used in simulating the ozone gas absorption cross-section to determine the simultaneous effect of optical path length and pressure at two peak wavelengths in the visible spectrum. Simulation outcomes were obtained for an optical path length of 10 cm to 120 cm showing that the optimum absorption cross-section value of 5.1084×10-25 m2/molecule at 603 nm and 4.7182×10-25 m2/molecule at 575 nm for gas cells length between 10 cm and 120 cm are obtained at peak points. Pressure values at which ozone gas absorption cross-section becomes a constant value of 5.1058×10-25 m2/molecule at 603 nm and 4.7158×10-25 m2/molecule at 575 nm is optical path length dependent. The percentage difference between 5.1084×10-25 m2/molecule and 5.1058×10-25 m2/molecule is 0.05% for all lengths of gas cells considered. Similarly, the percentage difference between 4.7182×10-25 m2/molecule and 4.7158×10-25 m2/molecule is also 0.05% for all lengths of gas cells considered. These results are relevant for high-accuracy and high-precision ozone gas measurements. Furthermore, efficient measurement of ozone gas is a direct enhancement of green communication.
Graphene-polyvinyl alcohol polymer based saturable absorption at 2000 nm region Nabihah Hussin; Asrul Izam Azmi; Mohd Rashidi Salim; Muhammad Yusof Mohd Noor; Ahmad Sharmi Abdullah; Michael David; Fauzan Ahmad; Mohd Haniff Ibrahim
Indonesian Journal of Electrical Engineering and Computer Science Vol 27, No 2: August 2022
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijeecs.v27.i2.pp701-708

Abstract

A graphene-polyvinyl alcohol (PVA) composite saturable absorption is demonstrated at 2000 nm region. Graphene suspension is produced using low-cost electrochemical exfoliation process. The suspension is mixed with PVA host polymer in 1:1 ratio and left evaporated at room temperature which finally produced graphene-PVA thin film. Thulium doped fiber (TDF) gain medium has been shown to produce a stable Q-switched pulse with a highest repetition rate of 54 kHz, a short pulse duration of 2.89 µs, a maximum peak power of 16 mW, and an estimated maximum pulse energy of 49 nJ. Apparently, at 2000 nm region, superior performances of graphene-PVA composite have been recorded which was largely contributed by meticulous composite preparation and homogenous mixture with PVA host.
Co-Authors Ahmad Sharmi Abdullah Asrul Izam Azmi Caroline O. Alenoghena Fauzan Ahmad Mohd Haniff Ibrahim Mohd Rashidi Salim Muhammad Yusof Mohd Noor Nabihah Hussin Patrick Enenche Sevia M. Idrus Tay Ching En Marcus