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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 ...
HO<sub>2</sub>, this radical readily reacts with nitrogen oxides and hydrocarbons in the atmosphere; in urban atmospheres, the major source of the hydroperoxy radical is formaldehyde photolysis.
Industry:Chemistry; Weather
Hydrocarbon compounds in which the carbon atoms are connected by a ring structure that is planar and joined by sigma and pie bonds between the carbon atoms. An example of an aromatic compound is benzene, C6H6.
Industry:Chemistry; Weather
Hypsometry is a technique of mapping the elevation contour of both land and the ocean floor using tinting to illustrate a change in contour.
Industry:Chemistry; Weather
If a change of state occurs from gas to liquid or liquid to solid, internal energy in the form of heat is released. If a change of state occurs from solid to liquid or liquid to gas, heat is required. Different compounds absorb and release different amounts of latent heat. Water releases nearly 600 kilocalories for each kilogram of water condensed.
Industry:Chemistry; Weather
In addition to photolytic destruction by infrared light (wavelengths of 1140 nanometers or less), stratospheric ozone is destroyed by interaction with a variety of chemical substances in the stratosphere. Some of these chemicals, such as the chlorine free radical--liberated by the photolysis of chlorofluorocarbons, are not normally produced there in nature at such high concentrations. This leads to the conclusion that human activities, and not natural chemical cycles, are responsible for the current rate of stratospheric ozone destruction. Ozone destruction is most noticeable (alarmingly!) over the South Pole, where seasonal plummeting in stratospheric ozone concentrations have been measured since the 1970s and are apparently still increasing (1999). That said, estimates based on declining CFC use (because of the Montreal Protocol) suggest that the damage to the global ozone layer will max out soon in the 21<sup>st</sup> century and that that ozone damage will decrease within the next 75 to 100 years.
Industry:Chemistry; Weather
In chemical terms, a propagation step is any step but the first, initial step, in a chain reaction (a series of chemical reactions in which the first reaction causes the second which causes the third, which causes the fourth, etc).
Industry:Chemistry; Weather
In chemical terms, a recombination is one of the ways in which free radicals are lost (the other being disproportionation). In this case, two free radicals join to create one product. This could be from a molecule that broke apart (ionized) and reconstituted, or two free radicals from different sources that form a new molecule.
Industry:Chemistry; Weather
In dry deposition this refers to the rate at which a gas particle is deposited onto another surface without the aid of precipitation. Vertical flux equals concentration of the species multiplied by the deposition velocity.
Industry:Chemistry; Weather
In general, clouds are classified and named according to their appearance and altitude at which they occur, being either high, medium, or low. Stratus clouds are low clouds, and as the root word suggests they are layered in appearance. They occur in broad sheets across most or all of the sky. Generally their formation is due to condensation within layered air that is not subjected to strong vertical movement.
Industry:Chemistry; Weather
In reference to ozone destruction, compounds formed in the stratosphere that sequester reactive chlorine and thereby remove it from a role in the catalytic destruction of ozone. Classic examples are HCl and ClONO<sub>2</sub>.
Industry:Chemistry; Weather
