- 行业: 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 ...
C<sub>6</sub>H<sub>12</sub>O, is a volatile organic compound (VOC) which are a large family of carbon-containing compounds which are emitted into the atmosphere from a variety of industrial processes. 2-hexanone may have the potential to contribute directly to global warming by absorbing infrared radiation from the earth's surface. In general the more complex a VOC, the greater its ability to absorb infrared radiation. 2-hexane may also contribute indirectly to global warming through the change in concentration of ozone, which is a potent greenhouse gas.
Industry:Chemistry; Weather
C<sub>6</sub>H<sub>5</sub>Cl, a colorless liquid that is manufactured for use as a solvent. It quickly evaporates in the air and is degraded by hydroxyl radicals that are produced photochemically. The gas acts as a source of ClO, which helps in the breakdown of stratospheric ozone.
Industry:Chemistry; Weather
C<sub>6</sub>H<sub>6</sub>, an aromatic hydrocarbon. It can be found in the air by several different ways of transmission. It can be produced for use with plastic or produced through the burning of fossil fuels. Benzene can also be found in the soil as well as some areas of groundwater pollution. In urban setting its presence correlates with the presence of NO<sub>x</sub> and CO. Exposure to benzene has been linked to leukemia.
Industry:Chemistry; Weather
C<sub>8</sub>H<sub>10</sub>, Colorless, flammable liquid with an aromatic odor, it is found in coal tar, petroleum, as well as in manufactured products like inks, insecticides, and paints. Ethylbenzene is also used to make styrene. It is during the manufacturing process that ethylbenzene becomes an airborne hazard. It takes about 3 days for ethylbenzene to breakdown into other chemicals. Exposure to ethylbenzene causes dizziness, throat and eye irritation, tightening of the chest, and a burning sensation in the eyes. The Occupational Safety and Health Administration (OSHA) has set an occupational exposure limit of 100 ppm of ethylbenzene for an 8-hour workday for a 40-hour workweek.
Industry:Chemistry; Weather
C<sub>8</sub>H<sub>20</sub>Pb, an organometallic compound used as a gasoline additive that prevents engine knocking. Leaded fuel allows for better efficiency and decreased knocking in internal combustion engines, but the lead released in car emissions, as lead oxides, is very toxic to humans. Lead would get deposited on the road and get mixed into urban dust. Teraethyl lead incorporation in gasoline was developed by Thomas Midgley, Jr. , later the inventor of chlorofluorcarbons. The advent of the catalytic converter's use in the 1970's precluded the use (in the U. S. ) of leaded gasoline because Pb poisoned the metals used in that device. TEL was therefore substantially phased out over the next 20 years.
1,2,3,4-tetramethylbenzene (C<sub>10</sub>H<sub>14</sub>)
1,2,3,5 Tetramethylbenzene.
Industry:Chemistry; Weather
C<sub>9</sub>H<sub>12</sub>, A colorless liquid with a gasoline odor, that is produced by petroleum refining, and combustion of petroleum products. It is a primary skin and eye irritant. Isopropylbenzene is used in paint thinner, additives to high octane aviation fuel, and the production of acetone. In the atmosphere it reacts with photochemically generated hydroxyl radicals. Its half life in the atmosphere is approximately 49 hours.
Industry:Chemistry; Weather
C<sub>9</sub>H<sub>12</sub>, A colorless or light yellow liquid. It is a primary solvent for cellulose acetate and is used in textile dying. It is naturally found in petroleum and bituminous coal and its main source is from the combustion of gasoline, landfill leaching and general use of asphalt. It has a molecular weight of 120. 9 g/mol and is also known as isocumene or phenylpropane. It has a melting point of -99°C, a boiling point of 159°C, and a vapor pressure of 3. 42 mmHg at 25°C. n-propylbenzene is flammable and incompatible with strong oxidizing agents. It is harmful if swallowed and is a respiratory irritant. N-Propylbenzene degrades photo-chemically with hydroxyl radicals in the atmosphere and has a half-life of 2. 7 days.
Industry:Chemistry; Weather
C<sub>9</sub>H<sub>12</sub>, an aromatic hydrocarbon commonly used as an industrial solvent and also commonly found in urban air as a molecule originating from urban traffic.
Industry:Chemistry; Weather
C<sub>9</sub>H<sub>7</sub>MnO<sub>3</sub>, an organometallic compound first sold as a gasoline additive. It was banned by the US Clean Air Act from 1977 to 1995. MMT has been found to be toxic to humans, but not in airborne concentrations, such as car emissions. Symptoms of MMT exposure range from skin and eye irritation to liver damage.
Industry:Chemistry; Weather
Calm, light winds, or squalls lying along the length of the equator. Winds which are part of the general circulation of the atmosphere, which are driven by the input of solar energy and modified by the rotation of the Earth. It is here that 17<sup>th</sup> and 18<sup>th</sup> century sailing ships had the most trouble making way and lack of fresh water or food sometimes spelled disaster.
Industry:Chemistry; Weather
