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Colorimetric methods for the determination of carbon monoxide in air and bloodLiu, Albert T January 2011 (has links)
Digitized by Kansas Correctional Industries
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The design and construction of a flashlamp-pumped frequency-doubled dye laser applicable to long path monitoring of air pollutantsJohnson, Joel Craig 01 January 1979 (has links)
The subject of this thesis is the development of a laser light source which could be used in an air pollution monitor to measure the average concentration of sulfur dioxide gas over long paths (>1 km). Many of the problems encountered in designing a long-path pollutant monitor such as instrument cost and reliability, the selection of an optimum spectral region for making the measurement, and light losses due to scattering and turbulence, are considered. The result of these considerations together with a survey of available laser light sources suggested that a frequency- doubled dye laser possessed several advantages over other laser light sources.
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Large-eddy simulation of transport of inert and chemically reactive pollutants over 2D idealized street canyonsChung, Nga-hang., 鍾雅行. January 2011 (has links)
In view of the worsening air quality in the world, more concerns are focused on the
environment. This thesis uses the technique of CFD and develops the computer model
to investigate the wind and pollutant transport, as well as the chemistry of reactive
pollutants in idealized two-dimensional (2D) street canyons.
Three scientific questions are raised in this thesis. The first task is to find out the po-
sition with the most favorable pollutant removal along the ground level over 2D idealized
street canyon of different building-height-to-street-width (aspect) ratios (ARs). The di-
mensionless parameter, C, represents the pollutant removal performance. In the isolated
roughness regime, the two local maximum C locate at the reattachment point and the
windward corner. In the wake interference regime, C is peaked on the windward side. The
number of vertically aligned recirculations depends on the street depth in the skimming
flow regime. The sizes of the secondary recirculation upstream and downstream deter-
mine how the maximum C shifts from the street centre. After identifying the position of
peaked pollutant removal rate at the ground level, the emission source should be placed
with the highest constant C in order to remove the pollutants upward more quickly to
safeguard the street-level air quality.
After understanding the best pollutant removal in the street canyon of different ARs,
the second task is to find out what AR is the most favorable for the ventilation and
pollutant removal across the roof level. The three parameters, namely friction factor,
air exchange rate (ACH) and pollutant exchange rate (PCH), are introduced to quantify
the pressure difference to sustain the mean flow, the ventilation and pollutant removal,
respectively. The turbulence contributes more than 70% to the total ACH and PCH in
all the three flow regimes. By increasing the atmospheric turbulence in building geometry
as well as the surface roughness, the ventilation and pollutant removal performance can
be improved. The linear relation between the friction factor and ACH demonstrates the
larger resistance that in turn promotes the air exchange over the roof level.
The physical dispersion is studied; however atmospheric pollutants are seldom in-
ert but chemically reactive instead. The last task is to include the three common air
pollutants, NO, NO2 and O3, in the simple NOx ?O3 mechanism in terms of the photo-
stationary state and reaction rates. The Damkohler numbers of NO and O3, DaNO and
DaO3, are parameterized by the concentrations of the sources NO and O3. The normalized
mean and fluctuation NO, NO2 and O3 are separately considered. The integrated pho-
tostationary state (PSS) in the first canyon increases with DaO3 under the same DaNO.
The integrated PSS of the second to the twelveth street canyons are compared with each
case, the monotonic increase in the PSS from the second to twelveth canyon is perceived
in DaNO/DaO3 1, 0.03, 0.02, 0.001 and 0.000333. Further decreases the DaNO/DaO3 to
0.000143, 0.000125, 0.000118, 0.000111 and 0.0001, the PSS is found to be non-linear and
the trough appears in the fourth and fifth canyons. / published_or_final_version / Mechanical Engineering / Master / Master of Philosophy
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Evaluation of chemcassette technology for monitoring low-levels of nitrogen-dioxideHazuka, John Anthony, 1964- January 1988 (has links)
Problems associated with instruments used to measure low levels of NO₂ include non-specificity, low sensitivity, and an uncharacterized dependence on environmental conditions. MDA Scientific has recently introduced a continuous colorimetric tape technique (chemcassette) to monitor for pollutant gases. Advantages of this technology include ease of use, fast-response alarm capability, and adaptability to measure different pollutants. This research characterized and compared chemcassette performance for NO₂ with other low-level NO₂ monitoring technologies including the luminox LMA-3 monitor and the EPA reference CSI chemiluminescnt monitor. The test protocol was based on EPA procedures. The chemcassette was found to be sensitive to temperature and relative humidity effects. The chemiluminescent monitor had the best overall performance. The luminox monitor displayed temperature dependence. Variation in stability of the chemcassette optical system, tape paper uniformity, and possible interference from ozone were characterized. (Abstract shortened with permission of author.)
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Near-ir tunable diode laser absorption spectroscopy of gaseous pollutants陳潔瑩, Chan, Kit-ying, Anna. January 1998 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy
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The nature and source of copper smelter particulate emissions and the effect of the nature on their electrostatic precipitator collectabilityWhyte, John Richard January 1980 (has links)
No description available.
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Trace sulfate analysis by flash volatilizationCauley, Henry Arthur January 1980 (has links)
No description available.
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Determination of nitrate ion in atmospheric particulate matter by solvent extraction with crystal violetBaca, Phillip Anthony January 1981 (has links)
No description available.
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Characterization of insoluble carbonaceous material in atmospheric particulates by pyrolysis/gas chromatography/mass spectrometry proceduresKunen, Steven Maxwell January 1978 (has links)
No description available.
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Release of radon from showers and its influence on the balance of radon indoorsHazin, Clovis Abrahao 08 1900 (has links)
No description available.
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