Kevlar
.... was found to form liquid crystalline solutions due to the repetitiveness of its molecular backbone. The key for the structural requirement for the backbone is para orientation on the benzene ring, which allowed for rod-like molecular structures. This technology was used when Du Pont released Kevlar aramid fiber in 1971.
What is it?
Kevlar is an aramid, a term invented as an abbreviation for aromatic polyamide. The chemical composition of Kevlar is poly para-phenyleneterephthala .....
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Polio
.... by-products into the atmosphere. Although wind and rain occasionally wash away the smoke given off by power plants and cars, the cumulative effect of air pollution poses a grave threat to humans and the environment.
In many places smoke from factories and cars combines with naturally occurring fog to form smog. Smog has been long recognized as a potential cause of death, especially for elderly persons and those with severe respiratory ailments (like asthma). Air pollution originally resulted from .....
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Plant Evolution
.... these developed root systems stems and leaves. They also formed woody tissue, which created stiffer stems, which eventually developed into tree trunks. They became tree-like and up to 40 meters tall, forming the world's first forest.
'The Age of Seed Bearing Plants' was the next stage of plant history where plants were taken to their next step up in the evolution. This occurred around 280 million years ago. This was also the dinosaur era. Earth began to become a lot drier, and these plants began to a .....
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Psychology
.... it is important and is information I need to hear. There is also selective hearing. Selective hearing is hearing only what you choose to hear, and my selective hearing was hearing my coaches and teammates’ voices. There are also perception cues in soccer. For example, the ball getting bigger when it comes closer to you, or the ball rolling faster the closer it gets. After several years of playing soccer I have adjusted to these perception cues, and have learned to handle different situations and how .....
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Pesticides
.... birth defects, and cancer due to hazardous pesticides. Although these health effects have not been proven in human life form, it has been proven that some pesticides are carcinogenic in lab animals. However, the bill overlooked many aspects of the agricultural industry and encompassed many loopholes. For instance, there were no requirements for the protection of infants and children. Pesticide residues, or rather allowable tolerances, were based on economic benefits. In other words, would it have an .....
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Pascals Triangle
.... But Pascal proved to be a child prodigy. At the age of twelve, he figured out the proposition of Euclidean geometry with no help. At the age of seventeen, he wrote an essay on conic sections which contained a theorum that was named after him.
Pascal also invented many things. He constructed the first digital calculating system for his father. He invented the syringe and the hydraulic press. He also established the principle of hydrostatics, known as Pascal's law. This law says that in a fluid at .....
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Photosynthesis
.... containing leaf material in the dark prior to illumination?
The reason this was done was to make sure as little oxygen as possible was contained in the leaf material. This coused the experimrnt to run properly. If the leaf material was not placed in the dark, the dark reaction would not have occured using up all the oxygen. If there was still oxygen in the leaf material, the data collected would have been off. The reason for this is that the leaves would have risen to the top of the liqiud quicke .....
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Protein Synthesis
.... In the cytoplasm there are free transfer RNA [tRNA] molecules which hve three protruding bases these sets of three on the tRNA are called anti-codons. Each tRNA molecule attracts different amino acids, of which there are around twenty, and they "stick" to the tRNA and depending on which tRNA molecule it is it wil attract a diferent amino-acid.On the RNA every three bases are called codons these are complementary to the anti-codons of the tRNA. For instance a codon of - GAA - would pair with the ant .....
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PyroTechnics
.... may detonate even if unconfined. Pyrotechnic special effects materials are Class B explosives. They will burn, but not explode unless confined. Examples are black powder and pellet powder, safety fuses, igniters, igniter cord, fuse lighters, Class B special fireworks, and Class B composite solids propellants. Class C explosives are common fireworks. Note that short lengths of Primacord may be classified as Class C under certain conditions. Both Class B and C explosives are also called low explosives .....
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Pollution Getting The Best Of
.... landscape. But people continue to consume and throw away more and more in the name of convenience. As they see it, when things
get old, throw it away and get a new one. They blame the government for the trash problem, but the truth blame should be placed on themselves.
The last great source of pollution lays in the businesses. Although not common, businesses have been known to dump their waste products into streams, lakes, and rivers. This may seem like a relatively small occurrence that re .....
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Plate Tectonics
.... much on plate tectonics, there are still some unanswered questions. The depths of the plates are still unknown. Scientists are still unsure on how the motion of the mantle was initiated. There are many theories on how plate tectonics works and why the polarization of the Earth switches every million years but there have been no concrete facts.
Plate tectonics needs to be explored more in order to solve much of the mysteries of the earth. It has already answered many questions about the geologic h .....
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Protein Synthesis
.... This occurs when RNA polymerase reads a codon region and the mRNA separates from the DNA terminating the sequence. There are special codon triplets, known as start and stop codons, which begin and end the process of transcription. At the end of transcription translation will begin except for in prokaryotes where transcription and translation can go on at the same time because of the lack of a defined nucleus.
The second part in protein synthesis is translation. Translation occurs in the cyto .....
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Prescribed Burning
.... with fire, there's always a chance one will escape," echoes his counterpart in California's Sierras.
"The fuels are tricky..." adds Ron Meyers, who directs prescribed fires for The Nature Conservancy from his base in Florida.
Such concerns are real.
Paul Tine, acting Forest Service fuels specialist for the sprawling eastern U.S. region, remembers well what he calls "the lowest day I've ever had in my 18-year career." As fire boss on a 40-acre prescribed burn on Minnesota's Superior National Fore .....
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Polio
.... to produce muscular relaxation. In the convalescent stage, occupational therapy is used.
Disease Control
Three broad types of the virus have been identified: the Brunhilde (type 1), Lansing (type 2), and Leon (type 3) strains. Immunity to one strain does not furnish protection against the other two.
Poliomyelitis control was made possible when, in 1949, the American bacteriologist John Franklin Enders and his coworkers discovered a method of growing the viruses on tissue in the labora .....
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Pesticides Are Affecting Our F
.... toxicity, immunotoxicity, and disruption of the endocrine system.” Children are more likely to be affected by pesticides than adults because, they are strange eaters, they breath at a higher rate, and tend to spend more time on the ground were chemicals may settle and then enter a child’s body through breathing, orally, by touching something with a residue and then putting their fingers in their mouth, and through a child’s skin. Pesticides will drastically damage the future health of our children if .....
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