Title

Ultrasensitive portable nitrogen dioxide monitor

School Name

Spring Valley High School

Grade Level

12th Grade

Presentation Topic

Physics

Presentation Type

Mentored

Written Paper Award

2nd Place

Abstract

The purpose of this experiment was to create a diode laser that could detect concentrations of NO2 both faster and more accurately than chemiluminescence. NO2 is a harmful greenhouse gas that leads to the formation of ozone. It was hypothesized for the first experiment that if the amount of NO2 in the cavity is increased, then the signal picked up by the detector will go down.The NO2 was inserted into a cavity at set amounts and measurements were taken using the diode laser. Measurements were taken every 0.5s for 50s and averaged. The sensitivity was then calculated by placing the averaged points for varying concentrations of NO2. The linear relationship between the integrated signal and NO2 concentrations was very strong for each test with R2 values over 0.99. It was hypothesized for the second experiment that if the integration time nears 10s, then the accuracy of the laser will increase. Zero air was run through the cavity and measurements were taken for 10 minutes at varying integrations times. The data was then assembled into an alan chart and a 10 second integration time was concluded to be the most effective.

Location

Neville 306

Start Date

4-14-2018 11:30 AM

Presentation Format

Oral and Written

COinS
 
Apr 14th, 11:30 AM

Ultrasensitive portable nitrogen dioxide monitor

Neville 306

The purpose of this experiment was to create a diode laser that could detect concentrations of NO2 both faster and more accurately than chemiluminescence. NO2 is a harmful greenhouse gas that leads to the formation of ozone. It was hypothesized for the first experiment that if the amount of NO2 in the cavity is increased, then the signal picked up by the detector will go down.The NO2 was inserted into a cavity at set amounts and measurements were taken using the diode laser. Measurements were taken every 0.5s for 50s and averaged. The sensitivity was then calculated by placing the averaged points for varying concentrations of NO2. The linear relationship between the integrated signal and NO2 concentrations was very strong for each test with R2 values over 0.99. It was hypothesized for the second experiment that if the integration time nears 10s, then the accuracy of the laser will increase. Zero air was run through the cavity and measurements were taken for 10 minutes at varying integrations times. The data was then assembled into an alan chart and a 10 second integration time was concluded to be the most effective.