- Industry: Education
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Founded in 1879 and named after Texas' greatest hero General Sam Houston, Sam Houston State University is public shcool within the Texas state university system and located in Huntsville, Texas.
It's a multicultural institution that offers 79 bachelorette degree programs, 54 masters and five ...
The scattering of light by a body with a particle diameter (D<sub>p</sub>) to wavelength ratio less than 0. 03 is termed Rayleigh Scattering. The wavelength of light scattered is dependent on the D<sub>p</sub>, and the amount of light scattered is dependent on the number of particles present per unit volume. Shorter visible wavelengths, such as blue, are scattered by smaller particles than are the longer wavelengths like red. This is the reason why, during daylight, the sky is blue when looking away from the sun. See also Visible Light.
Industry:Chemistry; Weather
The time that is required for a substance to reach fifty percent or one-half its initial mass. This can be radioactive decay or through chemical interaction. For instance, the half-life of carbon-14 is 5730 years; it decays to nitrogen-14. The atmospheric half life of hydroxyl radical (seconds) is not based on radioactive decay (it's radioactively stable) but on the chemical processes by which it is removed from the atmosphere. The half-life of atmospheric chemical species is often most strongly affected by reactions that have the fastest rate of reaction (see Reaction Rates).
Industry:Chemistry; Weather
This is the ratio between the actual water vapor content of the atmosphere and the maximum water vapor content possible at that given temperature. If the temperature of a given parcel of air rises, the amount of moisture it can hold increases and as such its relative humidity decreases. If there is no change in temperature but the moisture content decreases then the relative humidity will again decrease because the ratio of actual water vapor present is less than the maximum amount the air could hold. Conversely, if the water content does not change but the temperature falls, the relative humidity increases until saturation and possible precipitation occurs.
Industry:Chemistry; Weather
This is also called the ozone layer, where ozone concentrations are as high as 10 parts per million, and is a vitally important region of the atmosphere. This layer of ozone is located approximately 20-50 kilometers above the earth's surface. Stratospheric ozone is important because it prevents most of the high-energy ultraviolet solar radiation from reaching the earth's surface. Photodissociation, a photochemical process, is responsible for the formation of the protective ozone layer in the stratosphere. In the upper atmosphere, diatomic oxygen absorbs high-energy ultraviolet radiation. The absorption of radiation causes the diatomic oxygen molecule to break forming two oxygen radicals. The oxygen radical can then recombine with other diatomic oxygen molecules to form triatomic oxygen, or ozone. In the middle regions of the stratosphere, ozone is found in concentrations as high as 10 parts per million. Ozone can also form in the lower portions of the troposphere, due to anthropogenic activity and by a completely different mechanism. Without the protective stratospheric ozone layer in the upper atmosphere, life (as we know it) on earth would not be possible.
Industry:Chemistry; Weather
The product of the decomposition of fossilized carbon and organic matter in the crust of the earth. Generally, it is composed of mainly methane, and leaks are a source of methane in the atmosphere. It is also extensively mined, of course.
Industry:Chemistry; Weather
Very stable chemical compound, used in refrigerants, solvent, and (in the past in the U. S. ) aerosols, which release chlorine (important) and fluorine (less important) into the upper atmosphere. In the stratosphere, CFCs are photolyzed (by incoming solar UV) to form carbon dioxide, CO<sub>2</sub>, hydrogen fluoride, HF, and ultimately (after multiple UV absorption events) chlorine radicals. These chlorine species are crucial in the destruction of the ozone layer over Antarctica and probably elsewhere (see chlorine).
Industry:Chemistry; Weather
There are coal, crude oils, oil shales, tar sands and natural gases such as butane, ethane, methane which occur naturally from the decomposition of plant and sea and land organisms over millions of years. These natural resources contain stored energy from the sun which is released upon combustion. These fuels also release various types of pollutants such as sulfur dioxide, carbon dioxide and nitrogen dioxide when burned.
Industry:Chemistry; Weather
Volatile organic compounds, excluding methane, found in the atmosphere which are capable of producing radicals upon reaction with common atmospheric oxides and radicals; these compounds are often responsible for positive feedback cycles involving the production of ozone.
Industry:Chemistry; Weather
The process where a light wave's direction is changed due to the wave coming into contact with a different medium. In the atmosphere this especially involves particle diffraction of sunlight, diffraction that causes rainbows, cloud colors, and is the reason why the sky is blue and sunsets red.
1,2-Dimethylbenzene – A colorless liquid with a sweet odor that is classified as a volatile organic compound (VOC) found largely in the atmosphere in high-traffic urban areas 1,2-dimethylbenzene is primarily emitted into the atmosphere through exhaust and emissions from gasoline engines along with industrial emissions from processes such as coal distillation and petroleum refining. This compound is a threat not only in the atmosphere but also to water quality and land surfaces. High concentrations of 1,2-dimethylbenzene in the atmosphere can lead to irritation of the eyes, nose, throat, and can also cause severe breathing problems.
Industry:Chemistry; Weather
This is used as a industrial cleaner. One of the most abundant pollutants in water pollution. This chemical degrades and can produce vinyl chloride which is a carcinogenic to humans.
Industry:Chemistry; Weather
