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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Evaluation of Upper Atmospheric Ozone Data provided by a Differential-Absorption Lidar

Kubera, Kimberly 11 April 2005 (has links)
Ground-level ozone is an environmental and public health issue. Daily ozone forecasts are made to allow people to take precautions to protect their health. For this study, a prototype laser that measures ozone concentrations vertically throughout the atmospheric boundary layer was evaluated as tool for ozone forecasting. To examine this data, three analyses were performed. First, it was determined if stratification, and thus residual layers, could be seen. This was conducted, in part, by examining hourly mixing heights overlaid onto color-coded NEXLASER charts. Each NEXLASER chart shows the horizontal and spatial distribution of the measured ozone concentrations during a twenty-four hour period. In the second analysis, the correlation value between the early morning upper-tropospheric ozone and the maximum 8-hour average surface ozone concentrations was determined. For the third analysis, a case study on two select groups of days was conducted. This study suggested that NEXLASER can be used to detect the presence of residual layers and can be used as an aid in predicting peak daily 8-hour average ground-level ozone concentrations. Specifically, days on which a morning ozone reservoir layer is most prominent have the most potential to lead to high surface ozone concentrations later in the day. While more research should be conducted, this study shows how this data could be useful in explaining ozone events, and thus be an aid to ozone forecasters.
2

A study of the effect of pressure on the visible spectrum of ozone

Wilson, Frederick Samuel 08 1900 (has links)
No description available.
3

The reaction of ozone with an aqueous solution of: I thiourea, II sodium chloride

Little, Jess E. 05 1900 (has links)
No description available.
4

Balloon measurements of atmospheric ozone.

Walter, Bryan Robert. January 1969 (has links) (PDF)
Thesis (M.Sc.) -- University of Adelaide, Dept. of Physics, 1970.
5

Beiträge zur bildung des ozons durch ultraviolettes licht und hohe temperatur ...

Braehmer, Friedrich Wilhelm Leopold, January 1900 (has links)
Inaug.-diss.--Berlin. / Lebenslauf. "Literatur": p. 58-59.
6

Ueber die darstellung von ozon durch elektrolyse ...

Massenez, Carl Adolf, January 1906 (has links)
Inaug.-diss.--Berlin. / Lebenslauf.
7

Impact of Ozonation on System Performance and Growth Characteristics of Hybrid Striped Bass (Morone chrysops (f) x Morone saxatilis (m)) Reared in Recirculating Aquaculture Systems

Brazil, Brian Ligar 10 April 1997 (has links)
This study was conducted to evaluate the impact of sustained ozone dosages rates (0, 3, 13, 25, and 45 g O₃ per kg feed delivered per day)on water quality profile, fish physiology, and growth during a production cycle of hybrid striped bass reared in pilot scale recirculating systems. Nitrogenous wastes and dissolved organic compounds increased linearly (p < 0.01) throughout the trial under both ozonated and unozonated conditions. Ozone treatments 13 and 25 g O₃ / kg feed received 170 kg more feed than the control treatment (0 g O₃ / kg feed) by the end of trial. The ozonated system received an average 1 kg more feed per day than did the unozonated system, although the unozonated system received 25% more freshwater during the trial. Ozonation increased nitrification efficiency which resulted in a 25% reduction in residual ammonia measured per kilogram of feed delivered. Biologically degradable organics (CBOD5) were lowered 45% under ozonation when adjusted for daily feed input. Microbial activity as determined by the rate of degradation of DOC was 43% higher in the ozonated environments. Increased environmental quality provided through ozonation did not result in measurable physiological improvements (p 0.05). All parameters monitored except plasma protein and hematocrit values varied significantly (p>0.05) over time. Hemoglobin, plasma protein, and hematocrit values in fish under all rearing conditions were 10.2 ± 0.4 g/dL, 7.1± 0.6 g/dL, and 52.9 ± 1.9%, respectively. Final mean serum chloride level of 115.8 ± 3.4 mE/L and mean glucose level of 186.3 ± 2.1 mg/dL were measured in fish reared at treatments 0, 13, and 25 g O3. Fish reared under ozonated conditions possessed an overall mean growth rate of 2.3 g/day and FCR of 1.58:1. Simultaneously, fish in the unozonated environment gained 1.8 g/day at an FCR of 1.90:1. At the conclusion of the trial, the final mean weight (443 ± 11.6 g) of fish reared in the unozonated environment was significantly lower (p<0.01) than fish reared in the ozone treatments 13, and 25 g O3 (combined mean of 576.6 ±16.4 g). / Ph. D.
8

Ozonolysis in effluent and water treatment, and a study of recalcitrant compounds from biological sources

Robinson, P. J. L. January 1981 (has links)
No description available.
9

Mechanisms of natural climate change : the little ice age

Palmer, Michael January 2002 (has links)
No description available.
10

Atmospheric ozone retrieval using radiance measurements from the Chappuis and Hartley-Huggins absorption bands

Roth, Christopher Z. 27 March 2007
The monitoring of global ozone in the atmosphere is a necessary prerequisite to understanding atmospheric chemistry and managing atmospheric constituents. Satellite systems have been developed to measure ozone and other constituents accurately on a global basis. However, within this area there is considerable room for advancement in the techniques used to measure ozone from a satellite platform.<p>The Canadian instrument OSIRIS onboard the Swedish-led satellite Odin contains an optical spectrograph that is used for measuring limb radiance in the atmosphere. There are various proven techniques to convert limb radiance data into ozone density profiles. This work presents a new technique that combines radiance data from both the Chappuis and Hartley-Huggins bands to retrieve ozone density. The new technique extends the current upper limit of Chappuis-only retrievals from 40 km to 60 km.<p>The major portion of this work describes the implementation of this new technique. Briefly, a Multiplicative Algebraic Reconstructive Technique, together with the SaskTRAN radiative transfer model, is used to invert the limb radiance data into ozone density profiles.<p>An overview of the resulting ozone density profiles is presented together with comparisons against other ozone products as a first order verification of the results.<p>This work will be used to produce a new ozone data set from the OSIRIS limb radiance data consisting of ozone density profiles that are valid to 60 km.

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