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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.
201

Etude des pluies acides à Schefferville, N.Q. et de la possibilité de leur association à un transport atmosphérique de polluants sur de longues distances

Daoust, Mario. January 1982 (has links)
No description available.
202

Etude des pluies acides à Schefferville, N.Q. et de la possibilité de leur association à un transport atmosphérique de polluants sur de longues distances

Daoust, Mario. January 1982 (has links)
No description available.
203

The Influence of Acid Rain on the Engineering Properties of a Sensitive Clay

Hoppe, Edward 02 1900 (has links)
No description available.
204

The Effects of Soil Phosphorus on <i>Acer rubrum</i> Fecundity

Peters, Anna L. 11 June 2014 (has links)
No description available.
205

Spatial and Temporal Modelling of Water Acidity in Turkey Lakes Watershed

Lin, Jing 05 1900 (has links)
<p> Acid rain continues to be a major environmental problem. Canada has been monitoring indicators of acid rain in various ecosystems since the 1970s. This project focuses on the analysis of a selected subset of data generated by the Turkey Lakes Watershed (TLW) monitoring program from 1980 to 1997. TLW consists of a series of connected lakes where 6 monitoring stations are strategically located to measure the input from an upper stream lake into a down stream lake. Segment regression models with AR(1) errors and unknown point of change are used to summarize the data. Relative likelihood based methods are applied to estimate the point of change. For pH, all the regression parameters except autocorrelation have been found to change significantly between the model segments. This was not the case for SO4 2- where a single model was found to be adequate. In addition pH has been found to have a moderate increasing trend and pronounced seasonality while SO4 2- showed a dramatic decreasing trend but little seasonality. Multivariate dimension reduction methods are used to provide an overall graphical summary of the changes in TLW water system. We also report the result of applying segment regression for the analysis of first two principal components in selected stations. The results show that the efforts of the Canadian and US governments to reduce the emission of SO2 have been successful in controlling the acid rain problem in Eastern Canada. The project ends with suggestions for various extensions of the present work.</p> / Thesis / Master of Science (MSc)
206

State policy effects on sulfur dioxide emission allowance trading

Gilroy, Leonard 29 August 2008 (has links)
Title IV of the 1990 Clean Air Act Amendments established a market-based incentive approach to pollution control through the use of tradable allowances for sulfur dioxide (SO₂) emissions by electric utilities. Many researchers have theorized that this approach will be compromised by state regulatory policies that create incentives for utilities to invest in costly pollution control equipment, inhibiting the formation of a free and competitive allowance market. The pUrpose of this research is to investigate the impact of state regulatory policies on the development of the SO₂ allowance market. More specifically, this research examines whether the geographic distribution of traded SO₂ allowances (as determined by an analysis of EPA Allowance Tracking System data) has been affected by the actions of state regulators. The research also investigates the effect of Title IV on the Virginia coal industry. Several trends in the allowance market are identified in this study, including the declining price of allowances, over compliance at Phase I units, and the geographic patterns of trading. This research only partially supports earlier predictions that states with regulatory policies biased towards costly capital investments in flue gas desulfurization (scrubber) retrofits would become net allowance sellers in the national market. However, the research finds that these state policies, along with several other factors (including the Phase I Extension program, the tax treatment of allowances, and the risk-averse nature of utilities) have contributed to the slow growth in the allowance market. The research also concludes that Virginia low-sulfur coal producers are not benefiting from Title IV implementation. / Master of Urban and Regional Planning
207

Investigation of water vapor effects on the detection of nitric acid vapor with the tungstic acid technique

Marinaro, Ralph Michael January 1986 (has links)
An automated tungstic acid technique (TAT) has been successfully used to measure gaseous HNO₃ in the presence of water vapor. The TAT is based on the diffusion of gaseous HNO₃ to the interior walls of a tube coated with tungsten VI oxide (WO₃), where it is selectively chemisorbed. The collected HNO₃ sample is thermally desorbed from the WO₃ surface, as NO, and measured by a chemiluminescent oxides of nitrogen analyzer. The integrated analyzer response is directly proportional to the nitric acid collected. Based on nitric acid hydration characteristics, a decrease in the diffusion coefficient and thus collection efficiency for denuder type measurement techniques may result with increased atmospheric water vapor (i.e., relative humidity). This study emphasizes the effect of water vapor (i.e., relative humidity) as a potential interferent for HNO₃ collection with the TAT system. The effect of water vapor (< 78% RH) on the collection efficiency for HNO₃ with the tungstic acid technique is negligible at 25°C, but is significant only at elevated sampling temperatures. This threshold effect is further substantiated and eliminated when a modified sampling collection system was designed with coolant capabilities. The new design has been tested to sub-part-per-billion (NO<sub>x</sub> analyzer detection limit) levels with minimal loss of gaseous HNO₃ signal, thereby increasing sensitivity to atmospheric HNO₃ concentrations and maintaining the gas/aerosol sample integrity. / Ph. D.
208

Proposta de implementação de legislação ambiental, através de políticas de controle da poluição atmosférica, por meio de sistemas de monitoramento passivo / Proposal for implementation of environmental legislation through political control of air pollution

Muro Júnior, Aldo 28 June 2013 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-30T11:49:04Z No. of bitstreams: 2 Muro Júnior, Aldo-2013-tese.pdf: 3200192 bytes, checksum: 7297291a69938b3b69e4669ecb2b5490 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-09-30T15:31:14Z (GMT) No. of bitstreams: 2 Muro Júnior, Aldo-2013-tese.pdf: 3200192 bytes, checksum: 7297291a69938b3b69e4669ecb2b5490 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-09-30T15:31:14Z (GMT). No. of bitstreams: 2 Muro Júnior, Aldo-2013-tese.pdf: 3200192 bytes, checksum: 7297291a69938b3b69e4669ecb2b5490 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-06-28 / The aim... / O objetivo...
209

Effects of air pollutants on meteorological phenomena in the Indianapolis metropolitan area

Gardner, Mary L. 03 June 2011 (has links)
The effect of air pollutant emissions in the Indianapolis "Metropolitan area on the acidification of snow was studied. In the winter of 1979-80, several snowfall events were analyzed to determine the levels of acidity in precipitation. This study revealed that the Indianapolis Metropolitan area is contributing to the acidity of its snow. Samples collected near the city were more acidic than those in the outlying rural areas.The impact of meteorological elements, size specific atmospheric particle concentrations and total suspended particulates on prevailing visibility in the greater Indianapolis Metropolitan area was also studied. The most important factors which statistically contributed to decreased visibility were relative humidity, wind speed and total suspended particulates as measured by high volume sampling.Ball State UniversityMuncie, IN 47306
210

The influence of acid rain on mycorrhizae the roles of nitrate and sulfate ions and indole acetic acid in the development of Pisolithus tinctorius on Pinus taeda L. /

Andrews, Isaac M., January 1984 (has links) (PDF)
Thesis (Ph. D.)--Institute of Paper Chemistry, 1984. / Includes bibliographical references (p. 54-56).

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