S atmosphere

Interstellar clouds of gases contain mostly H, H2 and He, but the minority species are responsible for the interesting chemistry that takes place, just as in the earth s atmosphere. Interstellar clouds are divided into two... 

Ferguson E E, Fehsenfeid F C and Aibritton D L 1979 ion chemistry of the earth s atmosphere Gas Phase Ion Ghemistry ed M T Bowers (San Diego, CA Academic)... 

Rather different circumstances are encountered when considering THz remote sensing of extraterrestrial sources. The major source of THz opacity in the Earth s atmosphere is water vapour, and from either high, dry mountain sites or from space there are windows in which the background becomes very small. Incoherent instruments which detect the faint emission from astronomical sources can therefore be considerably more sensitive than their laboratory... 

Atmospheric corrosion results from a metal s ambient-temperature reaction, with the earth s atmosphere as the corrosive environment. Atmospheric corrosion is electrochemical in nature, but differs from corrosion in aqueous solutions in that the electrochemical reactions occur under very thin layers of electrolyte on the metal surface. This influences the amount of oxygen present on the metal surface, since diffusion of oxygen from the atmosphere/electrolyte solution interface to the solution/metal interface is rapid. Atmospheric corrosion rates of metals are strongly influenced by moisture, temperature and presence of contaminants (e.g., NaCl, SO2,. ..). Hence, significantly different resistances to atmospheric corrosion are observed depending on the geographical location, whether mral, urban or marine. 

The application of this last result to light scattered by the earth s atmosphere is especially interesting. The wavelengths of light at the red and blue ends of the... 

Both the a-X and b-X transitions have long been known from absorption by the oxygen in the earth s atmosphere, the source of radiation being the sun and the very long path length of oxygen overcoming their extreme weakness. For laboratory observation of these transitions, and particularly for accurate determination of absolute absorption intensity, CRDS has proved to be an ideal technique. 

The StabUity or persistence of a poUutant in the atmosphere depends on the poUutant s atmospheric residence time. Mean residence times and principal atmospheric sinks for a variety of species are given in Table 2. Species like SO2, (NO and NO2), and coarse particles have lifetimes less than... 

Fluorescent ultraviolet lamps within an apparatus that allows condensation cycles rather than the water spray typical of xenon arc tests have been developed for plastics testing (279). The spectral cutoff wavelength of the lamps used in the apparatus determines the severity of the test. Ultraviolet B (UVB) 313 lamps allow a significant irradiance component below 290 nm, which is normally filtered out by the earth s atmosphere. Ultraviolet A (UVA)... 

K. Narahad Rao and A. Weber, eds.. Spectroscopy of the Earth s Atmosphere and Interstellar Medium, Academic Press, Inc., Boston, Mass., 1992. 

Carbonyl sulfide is overall the most abundant sulfur-beating compound ia the earth s atmosphere 430—570 parts per trillion (10 ), although it is exceeded by H2S and SO2 ia some iadustrial urban atmospheres (27). Carbonyl sulfide is beheved to origiaate from microbes, volcanoes, and the burning of vegetation, as well as from iadustrial processes. It may be the main cause of atmospheric sulfur corrosion (28). 

At 25°C, pH 7.5, 1.5 ppm FAC, and 25 ppm cyanuric acid, the calculated HOCl concentration is only 0.01 ppm. Although the monochloroisocyanurate ion hydrolyzes to only a small extent, it serves as a reservoir of HOCl because of rapid hydrolysis. Indeed, this reaction is so fast that HClCy behaves like FAC in all wet methods of analysis. Furthermore, since HClCy absorbs uv only below 250 nm, which is filtered out of solar radiation by the earth s atmosphere, it is more resistant to decomposition than the photoactive C10 , which absorbs sunlight at 250—350 nm and represents the principal mode of chlorine loss in unstabilized pools (30). As Httie as 5 ppm of bromide ion prevents stabilization of FAC by cyanuric acid (23) (see also Cyanuric and ISOCYANURIC acids). 

Before drying can begin, a wet material must be heated to such a temperature that the vapor pressure of the contained Hquid exceeds the partial pressure of vapor already present in the surrounding atmosphere. The effect of a dryer s atmospheric vapor content and temperature on performance can be studied by constmction of a psychrometric chart for the particular gas and vapor. Figure 2 is a standard chart for water vapor in air (6). 

In order to see why, we need to look at our car in a bit more detail (Fig. 5.2). We start by assuming that it is surrounded by a large and thermally insulated environment kept at constant thermodynamic temperature Tq and absolute pressure po (assumptions that are valid for most structural changes in the earth s atmosphere). We define our system as (the automobile -1- the air needed for burning the fuel -1- the exhaust gases... 

Twomey, S., "Atmospheric Aerosols." Elsevier, North-Holland, New York, 1977. 

Time, Hours Wind Speed, m/s Atmospheric Stability Class... 

Air The composition of gases that make up the earth s atmosphere, approximately 79% nitrogen and 21% oxygen. Pure air has no definite meaning regarding the proportion of these gases this term is used to imply the absence of industrial particulate matter. 

Barometer An instrument used to measure the barometric pressure at a given location in the earth s atmosphere. 

In cyanobacteria and the eukaryotic photosynthetic cells of algae and higher plants, HgA is HgO, as implied earlier, and 2 A is O,. The accumulation of O, to constitute 20% of the earth s atmosphere is the direct result of eons of global oxygenic photosynthesis. 

Air is the source of six industrial gases, N2, O2. Ne, Ar, Kr and Xe. As the mass of the earth s atmosphere is approximately 5 X 10 million tonnes, the supply is unlimited and the annual industrial production, though vast, is insignificant by comparison. The composition of air at low altitudes is remarkably constant, the main variable component being water vapour which ranges from 4% by volume in tropical jungles to very low values in cold or arid climates. Other minor local variations result from volcanism or human activity. The main invariant part of the air has the following composition (% by volume, bp in parentheses) ... 

The noble gases make up about 1% of the earth s atmosphere in which their major component is At. Smaller concentrations are occluded in igneous rocks, but the atmosphere is the principal commercial source of Ne, Ar, Kr and Xe, which are obtained as by-products of the liquefaction and separation of air (p. 604). Some Ar is also obtained from synthetic ammonia plants in which it accumulates after entering as impurity in the N2 and H2 feeds. World production of... 

Ozone has received increased attention for its occurrence and function in the Earth s atmosphere.For example the decreasing ozone concentration in the stratospheric ozone layer, becoming most obvious with the Antarctic ozone hole. 

Man is able to directly utilize only a small portion of the energy of the Earth s atmosphere. Indeed, excessive concentrated energy in the atmosphere—hurricanes and tornadoes—represents risks to mankind. Most human demands created by atmospheric conditions involve consumption of energy to maintain comfort. The ambient surface air temperature, for instance, determines how much energy is needed for heating or cooling demands and the level of outside... 

Earth s atmosphere as seen from outer space. (National Aeronautics and Space Administration)... 

The two major ways by which humans get energy is to either burn fossil fuels or to burn wood for fuel. Both contribute substantially to air pollution, and both can have serious effects on (1) the health of plants and animals and (2) the workings of Earth s atmosphere. 

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