- Alternative Fuels for Vehicles
Conventional fuels such as gasoline and diesel are gradually being replaced by alternative fuels such as
gaseous fuels (natural gas and propane), alcohol (methanol and ethanol), and hydrogen. Conventional fuels
can also be modified to a reformulated gasoline to help reduce toxic emissions. Technological advances in the
automotive industry (such as in fuel cells and hybrid-powered vehicles) are helping to increase the demand
for alternative fuels.
- Conservation of Resources
Management of the human use of natural resources to provide the maximum benefit to current generations
while maintaining capacity to meet the needs of future generations. Conservation includes both the
protection and rational use of natural resources.
- Environmental Management
The development of strategies to allocate and conserve resources, with the ultimate goal of regulating the
impact of human activities on the surrounding environment. “Environment” here usually means the natural
surroundings, both living and inanimate, of human lives and activities. However, it can also mean the
artificial landscape of cities, or occasionally even the conceptual field of the noosphere, the realm of
communicating human minds.
- Green Chemistry
The pursuit and development of green (environmentally benign) technologies is one of the highest priorities
for today's chemists. The United States chemical industry generates approximately 350 million tons of toxic
waste per year, corresponding to more than 10 pounds per person per day. The safe disposal of this
hazardous waste comes at the high price of $20 billion per year. A significant source of chemical waste that is
often overlooked is the use of organic (or molecular) solvents. These solvents are deleterious to the
atmosphere because they are volatile liquids and thus difficult to contain. Nonvolatile ionic liquids (or molten
salts), composed exclusively of ions, are attractive substitutes for traditional molecular solvents. Sodium
chloride (NaCl) melts above 800ºC and could serve as a solvent for reactions proceeding at temperatures
greater than 800º. However, the number of feasible chemical reactions at such a high temperature is
limited. Room-temperature ionic liquids (RTILs), however, are salts that melt at or below ambient
temperature (~20º C or 70ºF), a quality that renders them useful as reaction media.
- Sustainable Materials and Green Chemistry
The conventional process for the production and use of materials has been to extract natural resources such
as fossil fuel or minerals, refine them, modify them further through manufacturing, and then distribute them
as products. At the end of their useful lives, the products are discarded, usually to a landfill or an incinerator.
Based on current material practices, society faces a number of problems, including the dispersion of
persistent toxics and other contaminants throughout the Earth, depletion of nonrenewable resources such as
petroleum, destruction of biodiversity, and the depletion and contamination of aquifers and drinking water
sources. There is a growing perception that these material practices are unsustainable.
- Wind Power
The extraction of kinetic energy from the wind and conversion of it into a useful type of energy: thermal,
mechanical, or electrical. Wind power has been used for centuries.
Articles courtesy of Access Science
http://www.AccessScience.com
Copyright McGraw-Hill, all rights reserved.
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