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In response to investi- gations of the accident, the NRC reformed its licens- ing and regulatory processes. Nuclear waste and its disposal. Unwanted radioactive materials are classified as low- level, transuranic, or high-level waste or spent nuclear fuel, depending on the concentration of radioactivity and the half-life of the radioactive material. In the United States, the 1980 Low-Level Ra- dioactive...
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Extensive work on air- pressure designs has been done by the British, the Norwegians, and the Japanese, who tested the Kaimei, an 80-meter ship with a number of chambers for test- ing various turbine designs, in the 1970’s. In the 1980’s and 1990’s, the Japanese worked on the Mighty Whale project, which consists of near-shore floating structures with three large...
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Oil and natural gas distribution. Oil and natural gas drilling and wells. Oil and natural gas exploration;. Oil and natural gas formation. The majority of the world’s reserves of crude oil and natural gas are concentrated in a few regions. About two-thirds of the world’s reserves are in Middle East nations. The United States has less than 2 percent of...
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Microscopic plant and animal life is abundant in much of the oceans. The majority of oil and natural gas deposits are believed to have been formed by such ac- cumulated marine organisms. Kerogen consists primarily of hydrocarbons that are in the solid state and that are insoluble not only in water but also in a variety of organic solvents.. The...
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These companies would do much the same vis-à-vis biofuels in the high-cost-petroleum era that followed the U.S.. The downturn in the price of oil in the 1980’s caused the majors to shut down most of their alterna- tive energy projects and to seek means for surviving in the lean years of the global recession. As these compa- nies would do...
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(Basalt is a dense black lava contain- ing about 50 percent by weight silicon dioxide formed as a result of melting of the mantle.) A sequence of these basalts looks like a huge pile of black to green pillows. Gabbro is the base of the crustal section and is underlain by mantle rocks called peridotite.. Ophiolites are common in rock...
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Some of the oxides are distributed throughout the world, while others are limited to a few regions. For example, magnetite can be found in the United States. hematite can be found in the United States, Venezuela, Brazil, Canada, and Australia. Oxygen is the most abundant element in the Earth’s crust (46.6 percent by weight), occurring mainly as oxides and silicates...
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Large mechanical guillotine cut- ters that operate at incredibly high speeds cut the mother sheet into smaller seg- ments and the finished sized sheets are delivered to the packaging department, then sent on to the consumer. In 2000, the countries with the largest paper and paperboard product output were first the United States, followed by Japan, China, Canada, Germany, Finland,...
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These fractures may be microscopic or may be vis- ible to the naked eye. Most of the world’s perlite is found in the western half of the United States. New Mexico supplies about three-quarters of the nation’s perlite. By the 1970’s, it was a common product used in the horticultural industry.. It is then crushed to the desired particle size...
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Petroleum refining and processing. Petroleum is first distilled, then each of the “cuts” is further treated or blended to pro- vide the various marketed products. Petroleum, or crude oil, is found in many parts of the world. Rather, petroleum is a complex mix- ture of hundreds of individual chemical compounds that occur in various proportions, depending on the source and...
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Forest Service, Pinchot became active in the Progressive Party, founded by supporters of Theo- dore Roosevelt. Placer deposits. Gold is soft and malleable but is otherwise nearly inert in the weathering realm. Hence, once gold is weathered out of the lode deposits where it ini- tially formed, the grains may survive transport in streams and rivers over long distances. It...
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The theory of plate tectonics provides an explanation for the present-day structure of the outer part of the Earth. Plate tectonic theory is based on a concept of the Earth in which a rigid, outer shell, the lithosphere, lies above a hotter, weaker, partially molten part of the mantle known as the asthenosphere. The thickness of the lithosphere varies between...
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gling small amounts of high-grade plutonium and uranium for sale in the West. After the terrorist attacks in the United States on September 11, 2001, fears of terrorists acquiring and using nuclear weapons were heightened. Plutonium: A History of the World’s Most Danger- ous Element. “The Actinide and Transactinide Elements.” In Chemistry of the Ele- ments. Controlling the Atom in...
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Producers of Portuguese olive oil who use the “protected denomination of ori- gin” label must use only olives from certain areas and follow a strict set of rules about the production of the oils. It produces about 9 percent of the tomatoes grown worldwide, with an average of about 864,000 metric tons per year, making it the eighth largest producer...
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Commercially, the clean-burning fuel is main- tained in the liquid state, which is obtained under conditions of elevated pressures, in a steel container.. As a result butane tends to be used in the south- ern United States, while propane (which condenses at −42° Celsius under normal pressure conditions is used in the North.. Modern Pe- troleum: A Basic Primer of...
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quartz crystals have been mined in Brazil, and smaller crystals are found in the United States—for example, in Arkansas and New York State (the “Herkimer dia- mond” deposits). Sec- ondary uses are found in the gemstone industry.. A striking example of quartz is the gradual petrifica- tion of trees, which occurs as the silica redeposits in the wood. Grasses such...
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These issues have become controversial in the United States.. and many ro- dents and insects), carnivores and omnivores (coy- otes, bears, weasels, eagles, spiders, and cougars), and decomposers that break down organic matter into el- ements that can be utilized by plants. Plants convert carbon dioxide and water into complex carbohydrates, fats, and proteins that can be utilized by animals...
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ing seismic studies to decode the in- terior of the Earth. Remote sensing developed from several origins, both scientific and technological. Technologically, the telescope, invented in the 1600’s, and photography, invented in the 1840’s, were significant advances in our abil- ity to remotely sense our environ- ment. Then, the discovery of energy (frequencies) beyond the familiar vis- ible light, in...
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Subtitle J, established in 1988 with the enactment of the MWTA, was a limited-duration demonstration project for tracking medical waste and regulating medical-waste handlers. facilities producing phosphoric acid and phosphate compounds were of particular concern because of the environmental threat posed by these chemicals. By making the mineral processing and mining sectors a nationwide priority, the EPA sought to protect...
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RFF researchers have been influential members of the Intergovernmental Panel on Climate Change (IPCC) and have helped in the formulation of U.S. Resources for the Future. Rhenium is widely distributed in the Earth’s crust in small amounts. In the United States, the richest con- centrations of rhenium are found in molybdenum ores in Arizona, Utah, and New Mexico. Rhenium (abbreviated...