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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 ...
A class of chemical substances found as a pollutant in the troposphere, formed by photolysis from natural and manufactured organic chemicals. These chemicals act as irritants and mutagens in mammals and are toxic to many plants.
Industry:Chemistry; Weather
A class of processes by which one material is taken up by another. Absorption is refers to the process of the penetration of one material into another; adsorption to the action of one material being collected on another's surface.
Industry:Chemistry; Weather
A colorless gas with a sweet odor. It was once used as a refrigerant in consumer products, but is no longer used because of its toxicity. It is central nervous system irritant, and in high doses can cause paralysis, seizures, and coma. Chloromethane was first synthesized by Peligot in 1835. Its chemical formula is CH<sub>3</sub>Cl, and it has a melting point of -97°C, a boiling point of -24°C, and is naturally produced by sunlight reacting with biomass and chlorine in the oceans. It was used industrially as a refrigerant. Chloromethane was also used to made lead based gasoline, but today it is mainly used as a chemical intermediate in silicone production.
Industry:Chemistry; Weather
A colorless liquid that was first used in 1842 as an anesthetic in surgeries by inhalation. This liquid is highly flammable and has volatile properties. It is commonly referred to simple as ether. Ethoxy ethane is prone to peroxide formation, and can form explosive diethyl ether peroxide, especially in old storage vessels. Ether peroxides are higher boiling and are contact explosives when dry. Symptoms of severe exposure may include coughing, chest pains, difficulty in breathing, nausea, headache, vomiting, or death.
Industry:Chemistry; Weather
A colorless liquid that was first used in 1842 as an anesthetic in surgeries by inhalation. This liquid is highly flammable and has volatile properties. It is commonly referred to simple as ether. Ethoxy ethane is prone to peroxide formation, and can form explosive diethyl ether peroxide, especially in old storage vessels. Ether peroxides are higher boiling and are contact explosives when dry. Symptoms of severe exposure may include coughing, chest pains, difficulty in breathing, nausea, headache, vomiting, or death.
Industry:Chemistry; Weather
A colorless, flammable liquid with the formula C<sub>9</sub>H<sub>12</sub>. It occurs naturally in coal tar and petroleum crude oil and therefore ends up in gasoline. It is a major component (typically 40%) of a petroleum refinery distillation fraction known as the C9 aromatic fraction. Oil refineries produce large amounts of this substance each year. Most of the C9 fraction is usually added directly to gasoline. Exposure to 1,2,4 trimethylbenzene can occur in the workplace or in the environment following releases to air, water, land, or groundwater. Vehicle emissions are a major anthropogenic source of 1,2,4-trimethylbenzene, due to its widespread occurrence in gasoline. Once in air, it breaks down and contributes to photochemical smog when it reacts with other volatile substance. This compound is also used by industries as chemical raw materials, paint thinners, and solvents.
Industry:Chemistry; Weather
A combination of carbon, hydrogen, sulfur, oxygen, nitrogen, and other trace elements synthesized or originating from natural sources such as plants and animals. Human excreta, paper products, food, agriculture and much industrial wastes are all examples of organic compounds. The degradation of organic matter by organisms in soil release gases such as H<sub>2</sub>S, NH<sub>3</sub>, CH<sub>4</sub> and CO<sub>2</sub> the last two both important greenhouse gases because of their long atmospheric lifetimes and IR absorption characteristics.
Industry:Chemistry; Weather
A combination of several gases and particulate matter that forms during a cover of fog or in the event of a low lying temperature inversion. The gases present include sulfur dioxide as a result of the burning of coal for use as energy, and the particulate matter included calcium sulfide as a result of acid deposition. In 1952, over a four day period, a temperature inversion trapped smoke and sulfur dioxide at dangerous levels, >4 mg/m<sup>3</sup> and >1. 3 ppmv respectively, both ten times the normal levels.
Industry:Chemistry; Weather
A complex cycle that circulates carbon through the atmosphere, oceans, and land which includes vegetation and soil and carbon is in various forms and oxidation states throughout the cycle.
Industry:Chemistry; Weather
A computer program that is used by atmospheric scientists to study and predict world-wide trends in weather patterns and the forces and physical laws that affect climate. The formulae are complicated and require skilled mathematicians, atmospheric scientists, and powerful computers for execution. Five regimes that influence climate are often taken into consideration: atmosphere, hydrosphere, biosphere, cryosphere, and pedosphere. Atmospheric and environmental physical laws as well as principles of thermodynamics and hydrodynamics are all used as part of the extensive mathematical parameters for the program. The results of these models are used as reference for other models, policy decisions, and by meteorologists.
Industry:Chemistry; Weather
