Atmospheric-Pollution Measurements

The group of special measurements include pajticularly studies using special vehicles, aircraft mapping of atmospheric pollution, measurements accomplished under abnormal conditions, measurements performed for preventing potential accidents, etc. 

Lidar systems for atmospheric pollutant measurement operate by... 

Allen, H. C. Brauers, T. Finlayson-Pitts, B. J. Illustrating Deviations in the Beer-Lambert Law in an Instrumental Analysis Laboratory Measuring Atmospheric Pollutants by Differential Optical Absorption Spectrometry, /. Chem. 

It is the use of LIDAR devices as tools for spectroscopic measurements on the various gases present in the atmosphere which concerns us here. These include ozone, carbon dioxide, the CFCs (chlorofluorocarbons, such as CFC-11, trichlorofluoromethane, and CFC-12, dichlorodifluoromethane, used as refrigerants) and all those molecules regarded as atmospheric pollutants. 

It has long been recognized that local environmental characteristics influence the rates of material corrosion. After two years of measurements at 39 sites in Europe and North America, significant relationships have been shown between corrosion rates of building materials and atmospheric pollutants( 5). While direction of exposure relative to weather and other factors such as frequency and duration of wetting significantly influence corrosion, Kucera (46) has shown that sulphur oxides are strongly correlated with deterioration of structural materials. 

When referring to sparse components of gas mixtures, scientists typically use parts per million (ppm) to designate the relative number of molecules of a substance present in a sample. Parts per million measures how many molecules of a substance are present in one million molecules of sample. As an example, concentrations of atmospheric pollutants often are given in ppm. If a pollutant is present at a concentration of 1 ppm, there is one molecule of the pollutant in every one million molecules of the atmosphere. In molar terms, I ppm means that there is one mole of pollutant for every one million moles of gas. Or, to put it another way, there is 10 mol of pollutant in every mole of air. 

Gas sensors are of importance for a variety of environmental, industrial, medical, scientific and even domestic applications. The gas may be, for example, hazardous to human health, an atmospheric pollutant, or important, in terms of its concentration, for an industrial or medical process. Apart from systems merely providing an alarm signal, it is frequently required to obtain accurate real-time measurements of the concentration of a particular target gas, often in a mixture of other gases. 

The significance of the measured properties of residual fuel oil is dependent to a large extent on the ultimate uses of the fuel oil. Such uses include steam generation for various processes, as well as electrical power generation and propulsion. Corrosion, ash deposition, atmospheric pollution, and product contamination are side effects of the use of residual fuel oil, and in particular cases, properties such as vanadium, sodium, and sulfur contents may be significant. 

The wavelength-dispersive x-ray spectroscopy method (ASTM D6376) provides a rapid means of measuring metallic elements in coke and provides a guide for determining conformance to material specifications. A benefit of this method is that the sulfur content can also be used to evaluate potential formation of sulfur oxides, a source of atmospheric pollution. This test method specifically determines sodium, aluminum, silicon, sulfur, calcium, titanium, vanadium, manganese, iron, and nickel. 

Jutze, G. A., and K. E. Foster (TR-2 Air Pollution Measurements Committee). Recommended standard method for atmospheric sampling of fine particulate matter by filter media—high-volume sampler. J. Air Pollut. Control Assoc. 17 17-25, 1%7. 

Photochemical oxidants are atmospheric pollutants produced by a series of reactions between hydrocarbons and oxides of nitrogen in the presence of sunlight. The recognized photochemical oxidants that have been measured in ambient air are ozone, the peroxyacylnitrates (mostly as PAN), and hydrogen peroxide. ... 

The potassium iodide method has been used extensively in California to measure the net oxidizing properties of atmospheric pollutants without identifying the particular species of oxidizing or reducing agents present. Studies have shown, however, that in California ozone is the major oxidant. At most sampling locations in California, the negative... 

In addition to the specificity of the monitoring method, an important requirement for the measurement of atmospheric pollutants is the accuracy of the calibration technique. The calibration procedure for the measurement of oxidants or ozone utilizes a stable and reproducible sample of dilute ozone in air. The ozone concentration of this sample is established with a reference method that is not necessarily suitable for monitoring ambient air. This reference method must agree with the scientifically accurate measurement of ozone in the calibration sample. 

Today I am going to speak about some of the continuous aerosol mass spectrometry methods that are currently in use. These methods are primarily used for atmospheric chemistry measurements related to human health such as pollution remediation, although now national security and homeland defense applications are starting to evolve. Most aerosol analysis methods are not realtime analyses bridging the gap between on-line and off-line technologies is a challenge that is being addressed. 

PERSONAL MONITORING IS A RELATIVELY NEW CONCEPT in community air pollution measurement research (1-3). This fact is not surprising because most air pollution investigations have been directed toward the characterization of the ambient atmosphere, the observation of pollutant trends, the acquisition of data on chemical kinetic parameters and on the physical properties of aerosols, and the determination of compliance to national and other standards (4). Before the late 1970s, research on personal monitors was primarily conducted in industrial settings (5, 6) because American Confer-... 

Radiotracers have been employed in studies of physical and biological processes in the atmosphere and the hydrosphere. Among the quantities that have been measured in atmospheric studies are the natural airflow patterns in large- and small-scale investigations, the dispersion of atmospheric pollutants from various sources, and the identification of the sources of various pollutants. In studies of... 

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