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Water Pollution, 2002.
This paper examines briefly the phenomenon of water pollution by both foreign matter and heat.
944 words (approx. 3.8 pages), 2 sources, MLA, $ 33.95
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Abstract
The paper lists the many sources of pollutants that can effect water, from chemicals to sediment from surrounding soil deposits. The writer then looks at the ways in which people are responsible for such pollutants. The paper concludes with a study of how scientists and government lobbyists are attempting to ameliorate the problem.
From the Paper
"Heat may also be considered a pollutant when increased temperatures in bodies of water result from the discharge of cooling water by factories and power plants. Although heat seems as if it would be relatively innocuous ? since heat will of course be dissipated from any body of water that it enters relatively quickly, and then further dissipated from the local atmosphere into the larger air basin. However, it must be remembered that raising the temperature of water depletes the oxygen available in it (heated oxygen molecules become excited and "gas out" of the liquid) and water that has a low-oxygen content is as deadly to aquatic creatures as a garage full of carbon monoxide is to a human. Aquatic animals suffering from the effects of thermal pollution may die, and their decomposing bodies will add to the pollutant levels of the body of water."
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Waves and Their Properties Analyzed in Light and Sound, 2002.
This paper examines the phenomenon of waves, looking to understand how waves work.
1,874 words (approx. 7.5 pages), 3 sources, MLA, $ 59.95
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Abstract
The paper first defines and categorizes waves, looking at the different media that can carry waves, such as liquid with waves in the ocean, solid with sound carried through a wall, or gaseous with light traveling through the atmosphere. The writer then gives the mathematical formulae for defining and understanding the way in which waves are formed and travel through space.
From the Paper
"There are a number of ways to categorize waves. One method is to categorize them according to the direction of the movement of the individual particles of the medium relative to the direction in which the waves travel. Three categories result: longitudinal waves, transverse waves, and surface waves. A longitudinal wave is a wave in which the particles of the medium move in a direction parallel to the direction in which the wave moves. Sound waves are an example of longitudinal waves. In a transverse wave, the particles of the medium move in a direction perpendicular to the direction in which the wave moves. Transverse waves require a relatively rigid medium in order to transmit energy due to the interaction of the particles that creates the perpendicular movement. As a result, only longitudinal waves flow through gas and the majority of liquids, even waves in the ocean."
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Global Positioning System, 2002.
This paper discusses the Global Positioning System (GPS) and includes technical data.
2,350 words (approx. 9.4 pages), 9 sources, MLA, $ 72.95
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Abstract
This paper explains that GPS provides all-weather round-the-clock navigation capabilities for the military and is an integral asset in numerous civilian applications and industries around the globe, including recreational uses such as boating, aircraft and hiking, corporate vehicle fleet tracking and surveying. The author states that the military's Precision (P) code provides positional accuracy to within approximately 20 meters. The paper reports that the first eleven spacecraft (GPS Block 1) were used to demonstrate the feasibility of the GPS system; the orbit inclination was 63 degrees, differing from the 55 degrees used for the operational system.
Table of Contents
Abstract
Background: Global Positioning System (GPS)
Problems to be Solved
Technical Discussion
Launch Facts
Future Prospects
From the Paper
"SLR will continue to be essential for measuring temporal variations of the gravity field given the passive simplicity of these orbit targets and the decadal span of precision data. With the launch of Lageos 2 in 1992 and Stella in 1993, in combination with the older geodetic satellites Lageos, Starlette, and Ajisai, estimates of the temporal variations of the gravity field will undoubtedly be improved in accuracy, and spatial and temporal resolution. Geophysical modeling of temporal gravity variations will also continue to be important, since their combination with the satellite estimates will improve our knowledge of the solid Earth, ocean, and atmosphere. The development of realistic eddy resolving multi-layer ocean models forced by real wind fields will be an important resource over the next few years for determining the role played by the atmosphere and oceans in the excitation of the Earth's gravity and rotational variations [Rosen, 1993]. Future improvements in the long-wave-length models of the time-invariant gravity field will depend on accurately modeling or estimating both the tidal and non-tidal gravity variations, as the current uncertainties for the low degree coefficients are at the same level as the known temporal variations of the coefficients. While tidally-induced variations have been modeled for many years, the importance of modeling non-tidal variations in gravity is only now becoming apparent."
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The Anoka Sandplain, 2002.
This paper discusses the geologic and environmental aspects of the Anoka Sandplain, a large sandy glacial outwash plain covering approximately 2200 square kilometers to the north of the Twin Cities Area in Minnesota.
750 words (approx. 3.0 pages), 4 sources, APA, $ 26.95
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Abstract
This paper explains the land use and management strategies of the Anoka Sandplain, which can be used for light industry such as sand and gravel mining, community districts such as business and residential areas and farming of alfalfa. The author believes that, when managing sandplains, we should take a cue from Mother Nature, which requires no outside inputs. The author feels that the best management is xeriscaping, which is landscaping that involves using plants that have minimal water requirements once established and require very little maintenance in general.
From the Paper
"Land management through erosion control is also important on the Residential and Commercial level. Practices in these areas include, the use of barriers preventing surface erosion from building sites to enter the natural environment. Also by using erosion blankets on loose soil, planting native grasses to hold soil, and by using retaining walls to hold critical slopes."
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"Toward a General Theory of Hurricanes", 2002.
Summarizes and analyzes the article, "Toward a General Theory of Hurricanes" by professor of meteorology Kerry A. Emanuel.
1,523 words (approx. 6.1 pages), 1 source, $ 50.95
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Abstract
This paper summarizes the article written by Prof. Kerry A. A. "Toward a General Theory of Hurricanes" which appeared in the July, 1988 edition of "American Scientist" and which calls for the placement of the physics of hurricanes in a more general context. The paper shows that Emanuel's reasoning behind this is that it would allow scientists to predict how the frequency and intensity of these storms would respond to changes in climate and allow scientists to relate hurricanes to seemingly different phenomena such as oceanic storms of the polar night and dust devils.
From the Paper
"The question of why hurricanes are so rare is considered next, for it is often known that there are several empirical condition that are necessary but not sufficient for the formation of hurricanes. There is some limitation which prevents these from being sufficient in most cases, and Emanuel considers a number of numerical simulations which may give a clue. He says there is a need for a strong starting disturbance, and this is consistent with the observation that real hurricanes never start spontaneously. The model of Rotunno and Emanuel is asymmetric and does not allow variations of the explicitly calculated fields around circles centered at the storm center. To start a hurricane, it was necessary to impose on the basic state a weak vortex which decays upward from the surface. This is the disturbance which starts the process toward a hurricane."
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The Ozone Layer, 2002.
A discussion of the different causes and their detrimental effects on the ozone layer.
1,884 words (approx. 7.5 pages), 7 sources, MLA, $ 60.95
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Abstract
This paper examines data on the effects of aircraft emissions on stratospheric ozone since the 1960s discovery that the emission of nitrous oxides and water vapor in the engine exhaust from supersonic transport planes may be destructive to the ozone layer. The ozone layer is the layer which keeps much of the sun's biologically harmful ultra-violet radiation from reaching the Earth's surface stratospheric ozone. It also analyzes how the continual destruction and production of ozone and the complex reactions between aerosols and exhaust emissions makes it difficult to assess the extent of the problem with currently available data.
From the Paper
"In 1971, Crutzen's theory was used to block the plan for the development of a fleet of high-speed supersonic aircraft (SSTs). It was believed that the nitrogen oxides in the exhaust from these planes would pose a serious threat to the ozone layer. As a result, the U. S. SST plan was abandoned. It is paradoxical that, while the environmental consequences of increasing the number of high-speed aircraft are viewed as being a serious threat to the ozone layer, air travel continues to increase annually (7). The demand for faster aircraft for travel to more distant destinations is spurring atmospheric chemists to research the effects of emissions from SSTs, and to develop ways to make engines whose exhaust is less damaging to the ozone layer."
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Earthquakes and Hurricanes, 2002.
A discussion of recent phenomena of earthquakes and hurricanes and their effects.
1,573 words (approx. 6.3 pages), 6 sources, MLA, $ 51.95
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Abstract
This paper examines the damage recently caused by the natural phenomena of earthquakes and hurricanes and measures that can be taken to to predict their arrival in order to prepare for them. In particular it looks at Hurricane Dennis, which menaced the coast of North Carolina and Hurricane Floyd, which led to a huge evacuation of people from Florida, Georgia and South Carolina. It also discusses the devastating effects of the two earthquakes that hit Turkey in 1999.
From the Paper
"The other major natural disaster in the fall of 1999 has been earthquakes, of which there have been several considered major in impact. Indeed, Turkey has been hit twice in different regions of the country. The earthquake in August left a death toll originally estimated to be about 500. This was a quake of magnitude 7.8 on the old Richter scale, making it almost as powerful as the 7.9 in San Francisco in 1906, which killed 700 people. The earthquake in Turkey struck at 3 am. Dozens of buildings collapsed. It is often noted in American cities when there is an earthquake at that hour that the death toll would have been much higher in the daytime when people were out on the street, but it is not clear that this would be true in areas like Turkey where buildings are not as well-constructed and where most of those killed were sleeping in their own beds when the house collapsed about them."
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A Look at the Big Bang Theory, 2002.
A study of the sources that support and question the Big Bang Theory of the beginning of the universe.
1,439 words (approx. 5.8 pages), 4 sources, MLA, $ 47.95
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Abstract
The writer gives a background of the Big Bang Theory and explores the theory as an explanation of the beginning of the universe. However, since the 1940s and the introduction of this theory, scientists have raised questions as to the validity of the explanation and continue to research other ways in which the universe might have been created. The paper traces some of this research.
From the Paper
"One such area of research has been the model for the expansion of the universe and so for the Big Bang. One theory offered to explain this is the inflationary model, and over the last two decades what has happened to this model shows some of the ways scientific truth is pursued and fine-tuned. Alan Guth developed the idea in 1979 and wrote it in his notebook. Inflation was the name for the mechanism Guth proposed for igniting cosmic expansion and which might have operated for as little as 10-35 seconds. Still, it would have whipped up all the matter and energy in the universe and laid the seeds for galaxies and galaxy clusters in that brief time, and in that time the universe would have blossomed exponentially from as small as 10-24 centimeters across to perhaps the size of a pumpkin. Michael Turner of the University of Chicago describes inflation as "the most important idea in cosmology since that of the big bang itself.""
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Loma Prieta Earthquake, 2002.
An analysis of the October 1989 Northern California earthquake.
900 words (approx. 3.6 pages), 2 sources, $ 31.95
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Abstract
Analysis of the October 1989 Northern California earthquake. Creation of the 7.1 magnifude quake by a slip in the San Andreas fault line. Depth of the quake. Occurrence of aftershocks and their magnitude. Areas of devastation; why some areas suffered greater damage than others. Landslides. Probability of a repeat high magnitude earthquake.
From the Paper
"1989 Loma Prieta Earthquake
The 1989 Loma Prieta Earthquake occurred at 5:04 PM on Tuesday, October 17, 1989. It was measured as a magnitude 7.1 on the Richter scale, a device utilized for measuring earthquake strength. It lasted about 20 seconds and was centered approximately 60 miles south of San Francisco. The tremor could be felt as far south as San Diego and as far east as Western Nevada. This earthquake was pinpointed along the San Andreas Fault line, long considered one of the most dangerous and active portions of the fault.
The famed San Andreas fault line runs along a northwesterly direction about 800 miles from the Gulf of California up to Cape Mendocino just north of San Francisco. This particular fault has been the source of many large quakes, including the 7.0 1838 quake on the..."
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Northridge Earthquake, 2002.
An analysis of the January 1994 Southern California earthquake.
900 words (approx. 3.6 pages), 1 source, $ 31.95
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Abstract
Analysis of January 1994 Southern California earthquake. Focal depth of 6.7 magnitude quake. Blind thrust type quake. The fault involved (Oak Ridge system, Pico thrust). Types of damage from the quake (liquefacation, lateral spreading, landslides, differential compaction). Greter damage to Santa Monica. Comparison to 1971 Sylmar earthquake. Retrofitting & engineering codes.
From the Paper
"1994 Northridge Earthquake
The 1994 Northridge Earthquake occurred at 4:30:55 AM PST on January 17, 1994. It was measured as a magnitude 6.7 on the Richter scale. This quake occurred along the Northridge Thrust, a fault that is also known as the Pico Thrust. It was centered about 20 miles northwest of Los Angeles and approximately 1 mile south?southwest of Northridge. This quake was a blind thrust type quake.
This particular fault dips to the south at an almost 45 degree angle. As a result, quakes along this fault and similar thrust faults falsely appear far removed from the surface trace. This particular fault forms the ridge slightly to the south of its trace, paralleled by the Santa Clara River and California Sate Highway 126. It begins near the town of Piru in the east and ends just..."
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Hermit Crabs, 2002.
Discusses different kinds of Hermit Crabs, their habitats and their characteristics.
1,125 words (approx. 4.5 pages), 4 sources, $ 39.95
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Abstract
Discusses different kinds of Hermit Crabs, their habitats and their characteristics. Usefullness in research. Series of activities of Hermit Crabs value for research into decision-making. Importance of shells and skill selection behavior. Ability of researchers to observe the assessment procedure of the crabs. Variouis experiments on Hermit Crabs in reference to animal behavior; response to stimuli.
From the Paper
"Hermit crabs usually are found in empty gastropod shells, seeking protection from predators, desiccation, and other hermit crabs. The hermit crab does not seem to select a place to stay at random but rather appears to have a selection process. Precisely what this process is and how the crab makes a decision as to what shell to select and what shell to reject is the subject of much research.
Hermit crabs are crustaceans that live in the wild in the western Atlantic. They mate on land near the sea, and once the eggs develop, the female carries the eggs on her abdomen to the sea and leaves them on wet sand or a wet rock for the tide to carry out to sea. There are usually 1,000 to 50,000 eggs at a time. At sea, the crabs are small larvae that molt several times in order to grow to adulthood. At the adult larvae stage..."
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Mount St. Helen?s, 2002.
A discussion of the volcanic Mount St. Helen's, its history, eruption process and aftermath.
1,621 words (approx. 6.5 pages), 9 sources, MLA, $ 52.95
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Abstract
This paper begins by providing a brief geological history of the mountain, seperating it into nine different periods. It then examines various lava types found in the area. The paper moves to modern day when the first actual threat was realized for eruption. It discusses the process of eruption and the different types of blast - lateral blast (direct blast zone, channelized blast zone, seared zone); vertical blast and pyroclastic flows. It concludes with an analysis of the aftermath and its effect on wildlife in the area.
From the Paper
"On May 18, 1980, Mount St. Helen?s in southwestern Washington erupted with a massive explosion. Leading up to this day was increasingly intense earthquake activity. There were also lots of relatively weak eruptions and many locations of minuet gas discharge. The devastating impact of the suddenly unleashed volcanic energy caused the worst volcanic and geological disaster in the recorded history of the United States."
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Radioactive Dating, 2002.
An introduction to the history and methods of the various types of radio carbon dating.
1,842 words (approx. 7.4 pages), 9 sources, MLA, $ 59.95
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Abstract
Radioactive dating is the process of determining the age of rocks and other specimens from the decay of their radioactive elements. By applying this information, geologists are able to decipher the 4.6-billion-year history of the earth. The paper introduces the history of this type of dating in chronological order. It discusses other issues related to radioactive dating such as Carbon-14 dating, fission track dating, Potassium Argon Dating, the Rubidium-Strontium method, lead-alpha age and debated ideas of radioactive dating.
From the Paper
"Cosmic rays from the sun strike nitrogen 14 atoms in the earth?s atmosphere and cause nitrogen atoms to lose a proton making it a carbon isotope this then turns into radioactive carbon 14, which combines with oxygen to form radioactive carbon dioxide. All living things are in equilibrium with the atmosphere, and the radioactive carbon dioxide is absorbed from the air and used by green plants. Then the radioactive carbon dioxide gets passed on through the plants into the food chain and the carbon cycle. All living things contain a constant ratio of Carbon 14 to Carbon 12 of about 1 in a trillion. The amount of carbon 14 lost in a species is continually replenished as long as it still takes in food and oxygen. At death, the exchange of carbon 14 ceases and any that is left in the tissues of the organism begins to decay to Nitrogen 14, this is not replenished by any new C-14. The change in the Carbon 14 to Carbon 12 ratio is the basis for dating this dating technique. The half-life is so short (5730 years) that this method can only be used on materials less than 70,000 years old. A lot of archaeological dating uses this method. It is also very useful in attempting to date remnants of the ice ages (Pleistocene epoch.)"
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Ozone Layer Depletion, 1995.
Examines causes and environmental effects, history, CFMs, statistics, ultraviolet radiation, U.S. and global corrective measures and the future.
1,350 words (approx. 5.4 pages), 10 sources, $ 47.95
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From the Paper
"OZONE LAYER DEPLETION AND ITS EFFECTS
Introduction
The ozone (O3) layer of the Earth's upper atmosphere exists from 50,000 to 120,000 feet (10:2127). Ozone at this level of the earth's atmosphere is generated by the absorption of ultraviolet radiation by oxygen (O2). In forming ozone, ultraviolet radiation of wavelengths between 290 and 320 manometers is absorbed and thus not allowed to reach the surface of the Earth. Concentrations of ozone are a few parts per million, variously estimated between 5 and 10 ppm (10:2127). Unstable ozone molecules are also constantly being created and destroyed by complex natural forces involving solar radiation and interactions with very minute quantities of other gases. Ozone concentrations fluctuate naturally on a daily, seasonal, and ..."
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Natural Disasters, 1995.
Discusses these in general and gives examples (the 1993 Midwest floods and the 1994 Southern California earthquake). Examines the impact on community infrastructure, basic services and insurance companies.
2,025 words (approx. 8.1 pages), 9 sources, $ 71.95
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From the Paper
"Introduction
Natural disasters come in many forms: floods, fires, earthquakes, tornadoes, volcanic eruptions and landslides are but a few of the calamities that people endure. It is when nature comes into conflict with humans that catastrophe results. The response to these natural disasters has been to invest in early warning systems in order to protect lives and property, and to offer residents and businessmen advice on how best to survive the types of disasters that any one area is prone to. Fortunately, not all parts of the world are subject to every type of disaster, which means that people in any one area have to prepare only for those disasters which are likely to occur in their area. Such preparation can take the form of developing evacuation programs and finding ways to minimize damage both to people, livestock and ..."
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