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Sam Houston State University (SHSU)
Industry: Education
Number of terms: 13055
Number of blossaries: 0
Company Profile:
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 ...
Cl<sub>2</sub>, molecular chlorine. In the stratosphere, atomic (radical) chlorine is very destructive because it depletes the greatly needed ozone layer which protects the earth from ultraviolet radiation from the sun. In the Antarctic stratosphere, molecular chlorine along with nitric acid are formed by the reaction of hydrogen chloride and chlorine nitrate--both stratospheric chlorine reservoir species. This process occurs on polar stratospheric clouds which serve as the reaction sites. Once formed, Cl<sub>2</sub> vaporizes into the surrounding air as nitric acid--also formed in that process--binds with the ice matrix. Cl<sub>2 </sub>is then photodissociated in sunlight (lambda <&#61; 450 nm) into chlorine radicals. These chlorine radicals then catalytic destroy ozone.
Industry:Chemistry; Weather
ClO, a radical species (with an odd number of electrons in its outer shell) which plays an important role in the breakdown of stratospheric ozone over Antarctica. Formed by the photolysis of CFCs in the stratosphere and the subsequent destruction of an ozone molecule, these radicals can act as a catalyst in the destruction of ozone while not being destroyed themselves. ClO, reacting with a oxygen atom (present from the Chapman Mechanism), releases a free chlorine radical once again. As a result, one Cl atom can destroy thousands of ozone molecules before being sequestered as HCl or another reservoir species (see chlorine nitrate).
Industry:Chemistry; Weather
ClO<sub>2</sub>, a radical, undergoes photodecomposition in the stratosphere where the products of this reaction react with ozone. Since this is a photochemical reaction it only takes place while the sun is up. Experiments over Antarctica have shown a direct relation between polar ozone loss and the increase in halocarbon chemistry, which comes from anthropogenic sources. Scientist are currently looking at the molecular behavior of chlorine dioxide in the atmosphere in order to understand its role in depletion of ozone more thoroughly.
Industry:Chemistry; Weather
ClONO<sub>2</sub>, this is a stratospheric reservoir species for chlorine and nitrogen, two of the catalysts in the breakdown of ozone. Frankly, it is named in a confusing manner; it is formed from the reaction of chlorine monoxide and nitrogen dioxide (not chlorine atoms with nitrate). It reacts with HCl at low temperatures on the surfaces of polar stratospheric clouds (PSCs over Antarctica and probably also in the stratosphere over the Arctic). That normally slow reaction heterogeneously produces molecular chlorine and nitric acid. The former outgases from the PSC surface and is quickly photolyzed by 450 nm or shorter wavelength light to form chlorine radicals which rapidly catalyze the breakdown of ozone (see chlorine monoxide).
Industry:Chemistry; Weather
Cloud droplets which attract an aerosol into snow, rain or some other water precipitate by coagulation and accretion.
Industry:Chemistry; Weather
Cloud formation consisting of dark-gray layers of clouds and occurring at altitudes which produce prolonged rain and snow.
Industry:Chemistry; Weather
Clouds forming in the troposphere which are vertically formed with flat bases and fluffy, rounded tops. They have often been described as cauliflower-like in structure. They occur at heights of 500-6000 meters in elevation from the earth and most often occur scattered or in dense heaped packs. They are formed due to buoyant upward convection during warm, anti-cyclonic summer weather.
Industry:Chemistry; Weather
Clouds that appear in a swirl of various colors. As a cloud of this nature forms it is composed of small droplets which are almost entirely uniformly spread; however this may change as the cloud grows. When the sunlight interacts with these droplets, and at a greater angle from the sun (for instance, sunrise or sunset but with the sun often hidden behind other clouds), solar radiation is scattered by the small droplets. This scattering occurs for different wavelengths approximately equally. That is why these thin clouds appear in a swirl of rainbow colors.
Industry:Chemistry; Weather
Clouds that occur in the stratosphere at altitudes above 20 km and are usually iridescent and luminous in color. They may also be called mother of pearl clouds.
Industry:Chemistry; Weather
CO, a toxic, odorless, colorless gas produced during fossil fuel or biomass burning. Compound consisting of one carbon and one oxygen. Except for carbon dioxide, it is one of the longest lived naturally occurring atmospheric carbon compounds (this wording is meant to exclude chlorofluorocarbons). The recent change in tropospheric CO content may portend a change in the balance between oxidants and reductants in the atmosphere.
Industry:Chemistry; Weather