Essay On Global Warming
.... gases are generated a number of human activities such as fossil fuel combustion, waste disposal in landfills, the use of a refrigerator, numerous agricultural and industrial activities, and the cutting down of numerous forests.
These human practices have already changed the chemical make up of the atmosphere. Between the pre-industrial times and today, we have seen the concentration of carbon dioxide rise 30% in some regions, in particular the northern hemisphere, human practices have increased concentrations of aerosols in atmosphere, which is a traditional form of air pollution), which tends to cool the atmosphere.
Wi .....
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Sedimentary Rocks
.... mineral layers or beds, which are distinguished from each other by differences in thickness, the size of the grains, or color.
All rock disintegrate slowly as a result of mechanical weathering and chemical weathering. Mechanical weathering is the breakdown of rock into particles without producing changes in the chemical composition of the minerals in the rock. Ice is the most important agent of mechanical weathering. Water percolates into cracks and fissures within the rock, freezes, and expands. The force exerted by the expansion is sufficient to widen cracks and break off pieces of rock. Heating and cooling of the rock, .....
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Polymers
.... Fiero.
New polymers are being created with more strength and flexibility by combing two chemically different polymers and producing a block copolymer. Combinations of block copolymers and composites and intended for use in booster rockets and in materials of Earth-orbiting installations.
Most common polymers are usually solid, but a new class of polymers is being introduced in a liquid crystal state. Although these polymers still have the physical characteristics of liquid, they are structured more like solids. Many liquid crystals are transparent at one temperature and colored at another temperature. This makes them suit .....
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Cellular Diffusion
.... other words, a movement down the concentration gradient. Osmosis is very similar to diffusion, however it involves the concentration of water. Osmosis, like diffusion, is a passive process, and does not require energy to occur. Active transport does require energy though, as it involves movement up the concentration gradient. This involves protein carrier molecules binding to the substance and moving it into or out of the cell, against the concentration gradient.
If a large molecule needs to be moved in or out of the cell, then two other processes, endocytosis and exocytosis are used. Endocytosis involves the cell membrane eng .....
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How Toxic Waste Affects Canada’s Natural Environment
.... If humans occupy the area, it could cause serious illness or death. For example, an area by Niagara Falls (US side) was used during the 1930s by a chemical company to dump its waste. Most of them were hazardous, and the containers that held the chemicals later (after the company had gone out of business) began to leak. The chemicals spread for miles killing off plants and causing cancers and deadly diseases in humans. Included in these wastes was a chemical called dioxin... one ounce of it used under the right circumstances was enough to kill off everyone in living in Toronto.
One of the most popular places to dump toxic w .....
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The Theory Of Evolution
.... this organic soup would form. Consider the experiment of Stanley Miller. In 1953, Stanley Miller passed an electric spark through an atmosphere of hydrogen, methane, ammonia, and water vapor; an atmosphere similar to the so-called "primitive atmosphere." But, this produced only 4 out of the 20 amino acids essential to form life. Interestingly, though, Miller saved the four amino acids only by removing them from the area in which the spark was generated. The book Life - How did it get here explained that "the same energy that would split the simple compounds in the atmosphere would even more quickly decompose any complex amino acid .....
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Glass
.... chemical, optical and thermal properties. Glass is an intriguing substance in the way that the moment you change the percentage of one of its components, the glass itself is different. (Education Dep. Properties: Chemical). Often, it can even be classified as a different type of glass. Commercial glasses are found in six basic categories, soda-lime glass, lead glass, borosilicate glass, aluminum silicate glass, ninety-six percent glass and fused silica glass.
Soda-lime glass is the most common and least expensive glass. Approximately ninety percent of all glass is soda-lime glass. Soda-lime glass contains between sixty and s .....
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Acid Rain
.... moves through every living plant and animal, streams, lakes, and oceans in the hydrologic cycle. In that cycle, water evaporates from the land and sea into the atmosphere. Water in the atmosphere then condenses to form clouds. Clouds release the water back to the earth as rain, snow, or fog. When water droplets form and fall to the earth they pick up particles and chemicals that float in the air. Even clean, unpolluted air has some particles such as dust or pollen. Clean air also contains naturally occurring gases such as carbon dioxide. The interaction between the water droplets and the carbon dioxide in the atmosphere, and to a l .....
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Black Smokers
.... Last summer a team from the University of Washington and the American Museum of Natural History accomplished the task of bringing four "black smokers" to the surface. The method that the team used for retrieval was quite interesting. The team followed a "loggers technique" for detaching the smoker from the Earth’s crust. They used a "choker", like the cables loggers use to drag downed trees to waiting trucks. Another "logger technique" that the team used was a chainsaw. But this one was different it was hydraulically driven and covered with a diamond-coated blade. Even thought the stacks are hard, they are also ve .....
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Clean Coal Technologies
.... or soft coal. It's the most plentiful type of coal in the States, and is mainly found in the eastern and middle part of the North American continent. Bituminous coal is primary used to generate electricity, and has a carbon content of 45 to 86 percent and a heat value of 10,500 to 15,000 Btu's. Sub-bituminous coal rank just below bituminous coal with 35 to 45 percent carbon content. The heat value of Sub-bituminous coal is between 8,300 and 13,000 Btu's per pound. It can be found in the western parts of the states. Lignite the lowest carbon content then the others "it usually has a brownish-black in color and often shows .....
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The Acid Rain Effects On Living Things
.... reactions. Rainwater, snow, fog, and other forms of precipitation containing these mild solutions of sulfuric and nitric acids fall to the ground as acid rain. Years ago, when smokestacks were only a few stories tall, pollution from the smokestacks usually stayed near the ground and settled on the land nearby. This only caused unhealthy conditions for plants and animals near the smokestacks. To reduce this pollution, the government passed laws permitting the construction of very tall smokestacks. At the time, people thought that if the pollution was sent high into the air it would no longer be a problem. Sending the pollu .....
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Drumlin Formation By Catastrophic Flooding
.... areas, by various workers. Shaw suggested as many as 10 meltwater discharges, similar to those which caused the Livingstone Lake drumlins, would be needed to account for drumlin fields in other areas [Shoemaker, 1995, p. 3].
The subglacial meltwater hypothesis of Shaw et al has several parallels to an interpretation of drumlins as streamlined landforms caused by the currents of flood waters generated by uplift, presented in the 1979 article Drumlins and Diluvial Currents by Cox. Although developed independently, Shaw's approach resembles that outlined by Cox in several ways. Cox published a photo with the above mentioned artic .....
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