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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

Removal and leakage of environmental tobacco smoke from model smoking room /

Chan, Tsz Tung. January 2009 (has links)
Includes bibliographical references (p. 90-100).
2

An analytical method to quantify 1,3-beta-delta-glucan using the LAL assay.

Foto, Mark S., January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2003. / Includes bibliographical references (p. 79-84). Also available in electronic format on the Internet.
3

A Modelling Study For The Health Risk Posed By Nuclear Power Plant In Bulgaria At Different Parts Of Turkey

Unver, Ozge 01 December 2003 (has links) (PDF)
In this study, following a severe accident at Kozloduy nuclear plant in Bulgaria how Turkey would be affected was investigated. The severe accident refers to core meltdown accident with catastrophic failure of containment. The model used is HySPLIT model developed in America. The worst day was predicted considering deposition of radionuclides. For initial runs, accidental release of I-131 and Cs-137 radionuclides was modeled for each day of year 2000 to find the worst day, seen to result from release beginning on April 7th 2000. After modeling release of all radionuclides for the worst day, radiation dose at different receptors, 12 most populated cities over Turkey has been calculated via different pathways. Late effects, fatal cancer, non-fatal cancer and hereditary risks, has been investigated for these receptors. The mostly affected part of Turkey was Marmara region and fatal cancer risk therein was 7x10-2 %. The collective health risk throughout Turkey was approximately 20 600 people. The same approach was then applied for investigating health risk of proposed nuclear reactor at Akkuyu, Turkey. In this case, the worst day was resulted from release beginning on 21st of February 2000. The worst affected part was the narrow strip in Central Anatolia extending to the north-eastern cost and fatal cancer risk in this region was 3.4x10-1 %. The collective health risk over Turkey was approximately 30 600 people. The results showed that Kozloduy nuclear plant has dominating effect throughout Turkey, but proposed Akkuyu reactor affects very limited region.
4

Comparison Of Iscst3 And Aermod Air Dispersion Models: Case Study Of Cayirhan Thermal Power Plant

Dolek, Emre 01 December 2007 (has links) (PDF)
In this study, emission inventory was prepared and pollutant dispersion studies were carried out for the area around &Ccedil / ayirhan Thermal Power Plant to determine the effects of the plant on the environment. Stack gas measurement results were used for the emissions from the power plant and emission factors were used for calculating the emissions from residential sources and coal stockpiles in the study region. Ground level concentrations of SO2, NOx and PM10 were estimated by using EPA approved dispersion models / namely ISCST3 and AERMOD. The ground level concentrations predicted by two models were compared with the results of ambient air pollution measurements for November 2004. Predictions of both ISCST3 and AERMOD were underestimating the ground level SO2 concentrations. However, AERMOD predictions are better than ISCST3 predictions. The results of both models had good correlation with the results of NOx measurements. It has been shown that the contribution of the power plant to SO2, NOx and PM10 pollution in the area studied is minimal.
5

Právní úprava ochrany ovzduší před znečišťováním z mobilních zdrojů / Legislation on air protection against mobile source pollution

Inquort, Vít January 2021 (has links)
Mobile sources, i.e. self-propelled or portable devices equipped with an internal combustion engine, are a significant contributor to air pollution and the regulation of air protection against pollution from these sources is an important part of environmental law. This area of law is currently evolving and changing very rapidly, as it is closely linked to a number of current issues, in particular climate change. The question posed by the diploma thesis is what is the current level of air protection against pollution from mobile sources in the Czech Republic, whether it is sufficient, and what is the possible development in the future. Therefore, the thesis contains a comprehensive analysis of current legislation, taking into account the various approaches by which the law seeks to regulate mobile sources and their operation, and includes topics such as introducing mobile sources to the market, regulating their operation, setting fuel quality requirements; further deals with legislation on alternative fuels and, last but not least, deals with legal instruments of air protection, which aim to maintain or improve air quality in a certain area in relation to mobile sources. Given that a significant part of the current legislation in the Czech Republic is based on international, and particularly on EU law, in...
6

Investigation Of Emissions And Combustion Kinetics Of Waste Wood Samples With Thermal And Spectral Methods

Yurdakul Yorulmaz, Sema 01 September 2006 (has links) (PDF)
The mechanisms and kinetics of combustion of waste wood as well as the phases during combustion processes are important to eliminate these wastes without any possible damage to environment. In the present study, combustion mechanisms, activation energy and pre-exponential constants, and phases of combustion were investigated for untreated natural pine and treated Medium Density Fiberboard (MDF), plywood and particleboard samples that involve some chemicals and additives. Waste wood samples were heated in air at 10, 20 and 30oC/min heating rates in a Thermo Gravimetric Analyzer (TGA) from room temperature to 900oC. Thermogravimetry (TG) and Derivative Thermogravimetry (DTG) curves for all samples were obtained. The gases formed during combustion reactions were directly fed to a Fourier Transform Infrared Spectroscopy (FTIR) instrument coupled to TGA. Emission characteristics of the samples were determined in-situ by using the FTIR spectrums. As a result of TG analysis, thermal decomposition of treated samples was observed at lower temperatures as compared to the untreated pine sample because of the catalyzing effects of the chemicals in the treated samples. Therefore, there were less flammable products, lower weight losses in the main oxidation region, decrease in the max. weight loss temperatures and formation of more char for treated samples as compared to untreated pine sample. In other words, chemicals used during production of these samples lead to decrease in the combustibility of the treated samples. Thermal kinetic constants for the samples were calculated by using Coats Redfern and Broido Methods. In order to find out the mechanisms responsible for the oxidation of the waste wood samples in different regions, six solid state mechanisms of Coats Redfern Method were tested. As a result of FTIR analysis of the emitted gases from TG analysis, several chemical groups were detected from pine and treated samples. Combustion of all samples revealed some gases containing aromatics, C-H groups, CO2 and CO. However, there were some toxic and carcinogenic gases like formaldehyde, isocyanate group, ammonia, phenyl group and benzoylbromide among the emissions of treated samples which need utmost attention when recovering energy from treated waste woods.
7

Chemical Composition Of Atmospheric Particles In The Aegean Region

Munzur, Basak 01 February 2008 (has links) (PDF)
Daily aerosol samples were collected at the &Ccedil / andarli which is located on Aegean coast of Turkey. A rural site was selected to monitor atmospheric pollution by long range transport. Sampling was performed in both summer and winter seasons, and in total 151 samples were obtained. Concentrations of elements in the samples were measured in order to identify sources and possible source locations of pollutants. Measured concentrations of trace elements at the &Ccedil / andarli station were compared with those measured at various sites around the world and, also in Turkey. As a result of comparison, level of pollution at the Aegean Region was found to be lower than the Mediterranean Region and Black Sea Region. Air flow climatology at &Ccedil / andarli was investigated in order to determine potential source regions for pollutants. Frequency of air flows from Russia and Western Europe are higher suggesting that emissions from these industrial regions affect the chemical composition of particulate matter. Besides these, it was concluded that contributions from Central and Eastern European countries are significantly high because of frequent air mass transport. Concentrations of elements measured at &Ccedil / andarli station were found to show short and seasonal variations. Such variations in concentrations are explained by variations in the source strengths and transport patterns. Positive matrix factorization (PMF) was applied to determine sources of elements and contribution of sources to each element. This analysis revealed 5 sources, two local anthropogenic emissions factor, one soil factor, one sea salt factor and one long range transport factor. Distribution of Potential Source Contribution Function (PSCF) values showed that main sources of SO42- are observed in Bulgaria, Romania, Poland, Ukraine and central part of Aegean region.
8

Development Of Gis Based Trajectory Statistical Analysis Method To Identify Potential Sources Of Regional Air Pollution

Yikmaz, Riza Fikret 01 May 2010 (has links) (PDF)
DEVELOPMENT OF GIS BASED TRAJECTORY STATISTICAL ANALYSIS METHOD TO IDENTIFY POTENTIAL SOURCES OF REGIONAL AIR POLLUTION Yikmaz, Riza Fikret M.Sc., Department of Geodetic and Geographic Information Technologies Supervisor: Prof. Dr. G&uuml / rdal Tuncel Co-supervisor: Assoc. Prof. Dr. Zuhal Aky&uuml / rek May 2010, 186 pages Apportionment of source regions affecting a certain receptor in the regional scale is necessary information for air quality management and development of national policy for exchange of air pollutants with other countries. Source region apportionment can be studied either through numerical modeling or by using trajectory statistics that is a hybrid methodology of modeling and measurements. Each of these approaches has their advantages and disadvantages. In this study treatment of back-trajectory segments in Potential Source Contribution Function (PSCF), which is one of the tools used in trajectory statistics will be investigated, to increase the reliability of the apportionment process. In the current method run in GIS, especially two parameters gains importance. One is that the vertical locations of trajectory segments are not taken into account at present. In this study, how the evaluation of the segments in 3-D instead of 2-D could improve the results will be assessed. The other parameter that is rainfall at each segment will be included in the PSCF calculations and its effects on the spatial distribution of PSCF values will be evaluated. A user interface in Geographical Information System (GIS) will be developed for effective use of improved methodology.
9

Investigation Of Non-methane Volatile Organic Carbon Emissions From Interior Materials Used In The Intercity Buses

Gormez, Baran 01 September 2004 (has links) (PDF)
The objectives of this study are to determine the non-methane volatile organic carbon emissions from the parts used in the interiors of buses at different temperatures and to analyze the components of these emissions. The total non-methane volatile organic carbon (NMVOC) concentrations in various sections of a bus were measured in order to determine the indoor air pollution in the bus. Different samples of the materials used in the interior parts of the buses were provided by the manufacturing company and they were tested in the METU Air Pollution Laboratory in order to see what hydrocarbon components make up this total NMVOC concentration.The results of experiments showed that the leading constituent emitted from the test pieces was toluene. Benzene concentration was very low. This is very important since benzene is a carcinogen and it has very low indoor concentration limits determined by OSHA and NIOSH. When the concentrations of the total NMVOC emitted from various parts are examined, it was seen that the most of the VOC emissions occur from the floor materials and ventilation channel. After measurements were done in two buses the average indoor total NMVOC concentrations were found as 21.15 &plusmn / 5.8 ppmv (as C3H8) and 46.04 &plusmn / 9.2 ppmv (as C3H8) in the first and second bus, respectively. Suggestions were made to the manufacturing company for some replacement of solvents and adhesives, and measurements were repeated with the newly manufactured parts for the bus. The highest concentrations were observed for toluene in these measurements, too. However, the toluene concentration was at least 40% lower than the initial values. Benzene concentrations were again very low. The average indoor total NMVOC concentrations were found as 10.41 &plusmn / 2 ppmv (as C3H8) in the measurements done in the bus decorated with new materials. This concentration was about 50% and 25% of the values measured in the first and the second bus at the beginning of the study, respectively.
10

Investigation Of Emission Factors Of Non-methane Hydrocarbons For Some Widely Used Passenger Cars In Turkey

Onoglu, Irem 01 September 2004 (has links) (PDF)
The objectives of this study are to measure the non-methane volatile organic carbon (NMVOC&#039 / s) emissions from passenger cars in Turkey having gasoline engines, to determine emission factors of these vehicles for BTEX compounds and comparison of emission factors obtained in this study with the emission factors of the other countries. This study was conducted in two parts: The first part was to determine the categories of passenger cars widely used in Turkey, and also to determine the average carbon monoxide (CO) and hydrocarbon (HC) emissions at idle condition for these car types based on the exhaust emission measurements of Ankara &Ccedil / evre Koruma Vakfi (AN&Ccedil / EVA). The second part of the study was to analyze the gas composition of exhaust gasses at different road conditions for BTEX components by using gas chromatography. The results of the study have shown that the cars named under &lsquo / &lsquo / Tofas&rsquo / &rsquo / constitute 31.5% and &lsquo / &lsquo / Fiat&rsquo / &rsquo / 13.1% of the total cars in Turkey and they are manufactured by the same company. Therefore, studies have been performed with &lsquo / &lsquo / Tofas/Fiat&rsquo / &rsquo / cars. The highest emission factors among hydrocarbons investigated in this study were found for toluene and m-xylene. Generally, as driving speed increases the emissions of HC&rsquo / s are found to decrease in concentration. It was interesting to note that the highest emissions occur at 30 km/hr speed which is the mostly used speed in crowded streets and busy intersections. Therefore, it was concluded that it is very important to take measures for emissions in the city traffic. Cold start emissions were also found to be higher than the hot start emissions.

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