Measuring Atmospheric Ozone and Nitrogen Dioxide Concentration by Differential Optical Absorption Spectroscopy

Measuring Atmospheric Ozone and Nitrogen Dioxide Concentration by Differential Optical Absorption Spectroscopy

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Date: December 2011
Creator: Jerez, Carlos J.
Description: The main objective was to develop a procedure based on differential optical absorption spectroscopy (DOAS) to measure atmospheric total column of ozone, using the automated instrument developed at the University of North Texas (UNT) by Nebgen in 2006. This project also explored the ability of this instrument to provide measurements of atmospheric total column nitrogen dioxide. The instrument is located on top of UNT’s Environmental Education, Science and Technology Building. It employs a low cost spectrometer coupled with fiber optics, which are aimed at the sun to collect solar radiation. Measurements taken throughout the day with this instrument exhibited a large variability. The DOAS procedure derives total column ozone from the analysis of daily DOAS Langley plots. This plot relates the measured differential column to the airmass factor. The use of such plots is conditioned by the time the concentration of ozone remains constant. Observations of ozone are typically conducted throughout the day. Observations of total column ozone were conducted for 5 months. Values were derived from both DOAS and Nebgen’s procedure and compared to satellite data. Although differences observed from both procedures to satellite data were similar, the variability found in measurements was reduced from 70 Dobson units, with ...
Contributing Partner: UNT Libraries
The Disfigured Muse : Supreme Readers in the Poetry of Wallace Stevens

The Disfigured Muse : Supreme Readers in the Poetry of Wallace Stevens

Date: August 1993
Creator: Hobbs, Michael B. (Michael Boyd)
Description: In "Discourse in the Novel," Mikhail Bakhtin tells us that "Every discourse presupposes a special conception of the listener, of his apperceptive background and the degree of his responsiveness." My study of Wallace Stevens's poetry examines Stevens's "conception of the listener"—in the form of his intratextual readers, their responsiveness, and the shapes that responsiveness takes—and attempts to formulate out of that examination Stevens's theory of reading embodied in his canon of poems.
Contributing Partner: UNT Libraries
Attitudes of Faculty Members in Rajamangala Institute of Technology, Thailand, Toward the Implementation of Computers

Attitudes of Faculty Members in Rajamangala Institute of Technology, Thailand, Toward the Implementation of Computers

Date: May 1992
Creator: Cheamnakarin, Pornpimon
Description: This study explored the attitudes and perceptions of faculty members in Rajamangala Institute of Technology (RIT), Thailand. The purpose of this study was to (a) determine which demographic variables are associated with faculty members attitudes toward the implementation of computers in higher education in Thailand, and (b) determine perceptions among faculty members toward barriers to the widespread use of computers.
Contributing Partner: UNT Libraries
A Study of the Effectiveness of Using Computer- Assisted Instruction for Teaching the Interpretation of Weather Reports and Forecasts to College Students

A Study of the Effectiveness of Using Computer- Assisted Instruction for Teaching the Interpretation of Weather Reports and Forecasts to College Students

Date: May 1993
Creator: Payne, John William, 1946-
Description: The purpose of this study was to assess the effectiveness of computer-assisted instruction (CAI) as a method of delivery. Student attitude toward method of instruction was examined. Additionally, the amount of study time required by the students was observed.
Contributing Partner: UNT Libraries