Реферат: Nuclear Radiation

Nuclear Radiation

Viktor Chernobay                                                                                         Biology 115                             

<span Times New Roman",«serif»">     Nuclear energy was discovered in theprocess of creating the atomic bomb. After scientists conducted more experiments, they found that nuclearpower was a clean and efficient way to produce energy.  “The first nuclear reactor was created onDecember 2, 1942, at the University of Chicago by Enrico Fermi.” (Editors ofScientific America, 1995).  The discoveryof nuclear energy provided a new source of energy and an alternative to the useof natural resources: such as coal, oil, water, and wood.  At the same time, nuclear energy could beused in a destructive way, such as  theatomic bomb.

<span Times New Roman",«serif»">     Atthat time, the discovery of a new source of energy was a very significantevent. By using a small amount of plutonium and uranium, two radioactiveelements, an enormous amount of energy could be obtained.  Nuclear energy can be produced in twodifferent ways, by the fission or fusion process.  Fission involves the breaking up of heavieratoms into lighter atoms.  In a nuclearfission reaction, two smaller nuclei of approximately  equal mass are formed from the splitting of alarge nucleus.  This splitting of an atomproduces a large amount of energy.  Thisprocess is the most common form of nuclear power.  Fusion is a method that combines lighteratoms into heavier atoms.  In a nuclearfusion reaction, a large nucleus is formed from two small nuclei joinedtogether.  Fusion reactions are difficultto produce because of the repulsion of the atom’s negatively charged electronclouds and the positively charged nucleus. (LeMay, Beall, Robblee, Brower,1996).    Fusion is mostly used to createthe hydrogen bomb. (The World Book Encyclopedia, 1990).  The byproduct of nuclear energy isradiation.  Radiation is created from theparticles (strontium-90, cesium-137, radon-222, krypton-85, and nitrogen-16)that are given off as a result of the splitting of  atoms. (Gale Encyclopedia of Science, 1996)(Demmin, 1994).

<span Times New Roman",«serif»">     As time went on, the attitudes of peopletowards nuclear energy changed.  Therewere many positive and negative aspects for the use of nuclear power.  Recently, people worldwide have startedquestioning the continued use of nuclear power. Due to the deaths resultingfrom the 1986 Chernobyl nuclear reactor accident, as well as the adverse effectthe aftermath of the accident had on the environment, there has been a publicoutcry concerning the safety of society. As with many controversial issues,this topic has been widely debated, but a solution has not been determined.

<span Times New Roman",«serif»">     The positive aspects of the use of nuclearenergy are that the supply of natural resources does not have to be depleted,and also it is clean.  It takes a greatamount of natural resources to create a small amount of energy.  On the other hand, a very small amount ofplutonium and uranium is necessary for the creation of a large amount ofnuclear energy.  This is important sincethere are relatively small amounts of plutonium and uranium in the earth’scrust.  Compared to the production ofpower using coal, the creation of power generated by nuclear energy does notpollute the air.  As coal burns, thereare poisonous fumes that could cause sickness, if the area is not properlyventilated.  As the cost of electricityrose, the government was forced to look for an alternative source of energy,which they discovered in nuclear reactors.

<span Times New Roman",«serif»">     One of the major disadvantages of areactor is the disposal of the nuclear waste which harms the environment.  “There are 434 nuclear reactors in the worldand 110 of them are in the United States.” (Wasserman, 1996)  Not a singleone is functioning without polluting the environment.  Attempts to store nuclear wastes have notbeen very successful.  One such attemptis to bury the nuclear waste underground, but the leakage of nuclear waste haspoisoned the groundwater.  Anotherattempt is to put the nuclear waste into deep ocean water.  Later, this was rejected by the public andalso, in violation of an international treaty because of the possibility ofharming the ocean.  Another problem tothe environment is the leakage of radioactive waste from space.  This problem is not pollution to the earth’s environment,but pollution of space.  There is no wayto dispose of the nuclear waste in space.

<span Times New Roman",«serif»">     The most significant drawback on thiscontroversial issue is the threat of a disaster.  The two most serious situations were theaccident at Chernobyl and the explosion of the hydrogen bomb on Hiroshima. Thefirst time that people discovered the dangers of nuclear power was when theatomic bomb was dropped, August 6, 1945, on Hiroshima.  The effects of the bomb was that it destroyed4.7 square miles of the city. Approximately 70,000 people were killed and about another 70,0000 peoplewere injured.  Many people died later asa result of nuclear radiation and radiation sickness. (The World BookEncyclopedia, 1990).  The most seriousnuclear disaster was the  Chernobylaccident that occurred April 26, 1986 in the Soviet Union. (Medvedev,pp.83-89.).  An accurate number of deathsas a result of this accident is very hard to determine due to the secrecy ofthe U.S.S.R. surrounding this accident. (Marples, 1996).  A study done by a team of scientists fromboth the United States and Japan has shown that there has not been any evidencefound of genetic mutation, which are changes in heredity, in the children ofthe survivors of the bombing of Hiroshima. (Science News, 1996).

<span Times New Roman",«serif»">     Following the Chernobyl accident, Sovietscientists suggest that there is evidence that radiation has exhibited geneticmutation in the parents who were exposed to radiation.  According to them, the mutation was found insperm and egg cells, which contain the genetic building blocks of futuregenerations. The child’s DNA is a combination from both parents’ geneticmakeup.  When there is any sequence thatthe child has, but that sequence was not found in either parent, then this iscalled germline mutation.  Ten yearsafter the accident that occurred at Chernobyl, evidence of mutation, in theexposed areas of the country, indicates that radiation changed genetic makeup and that this has passed onto futuregenerations. (Science News, 1996).  Also,there has been an explosive increase in childhood thyroid cancer in Belarus,Ukraine and the Russian Federation since 1986. This cancer is present in brothers and sisters of the same family, whichindicates that the cancer is a result of the accident at Chernobyl. (Balter,1995).

<span Times New Roman",«serif»">     Whether the atom is used for peace or forwar, man must contend with the hazards of nuclear radiation.  This radiation may cause burns, diseases, anddeath.  It may harm future generations bycausing mutations.

<span Times New Roman",«serif»">     In peacetime, the escape of radioactiveparticles from nuclear plants is the main radiation hazard.  More nuclear power plants will be builtif  a significant amount of the world’spower is to come from  uranium.  As a result of these plants, huge amounts ofradioactive material will be produced. The power plants must take necessary precautions to insure thecommunities are safe from the radiation that may escape.

<span Times New Roman",«serif»">     In wartime, the most serious danger fromradiation is near or below the place where the atomic bomb has exploded.  If people are not killed by the bomb, thenthey have to deal with the radioactive fallout. Even at a distance from the blast, the injury can be serious.

<span Times New Roman",«serif»">     The use of radiation has many positiveattributes, but at the same time, the significance of the drawbacks areoverwhelming.  No government norscientist can guarantee the safety of nuclear plants.  Without this guarantee, there is an immediateconcern for the welfare of the world.  Ibelieve countries around the world should begin a gradual process of shuttingdown nuclear plants and begin making a much greater effort to developwidespread use of other sources of energy, such as wind and solar power.

<span Times New Roman",«serif»">     In the last decade, public concern for theuse of nuclear energy has increased dramatically.  Few can debate that nuclear energy is clean,and can be produced without using hardly any natural resources.  Likewise, few can debate that radiation isharmful to the environment, unsafe, and a great danger for all livingthings.  Scientists and mankind have toweigh the positive as well as the negative aspects of nuclear radiation, andthen decide what source of energy the future holds that will benefit not onlyall living things, but also the environment.     

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<span Times New Roman",«serif»">REFERENCES

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<span Times New Roman",«serif»">Balter,Michael. ( 1995). “Chernobyl’s Thyroid Cancer Toll.” Science. vol. 270, no. 5243, pp. 1758-1759.

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<span Times New Roman",«serif»">Demmin,Peter E. (1994). Reviewing Chemistry. AmscoSchool Publications, Inc. New York. P. 85.

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<span Times New Roman",«serif»">LeMay,Eugene H. Jr., Beall, Herbert, Robblee, Karen M., and Brower, Douglas C.(1996). Chemistry Connections to Our ChangingWorld. Prentice Hall. New Jersey. Pp. 792-798.

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<span Times New Roman",«serif»">Marples,David R. (1996). “The Decade of Despair.” TheBulletin of the Atomic          Scientist. vol.52, no.3, pp.22-31.

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<span Times New Roman",«serif»">Medvedev,Grigori. (1991). The Truth About Chernobyl.Basic Books. A Division of Harper Collins Publishers. pp. 83-89.

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<span Times New Roman",«serif»">Science News

<span Times New Roman",«serif»">.(1996). “Radiation Damages Chernobyl Children.” editors of Science News. vol. 149, no. 17, p. 260.

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<span Times New Roman",«serif»">ScientificAmerican

<span Times New Roman",«serif»">. (1995). “Disposing of NuclearWaste.” Editors of Scientific American.p. 177.

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<span Times New Roman",«serif»">The GaleEncyclopedia of Science

<span Times New Roman",«serif»">. (1996).Bridget Travers, editor. New York. vol. 5, pp. 3008-3009.

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<span Times New Roman",«serif»">The World BookEncyclopedia

<span Times New Roman",«serif»">. (1990). Field EnterprisesEducational Corporation. Chicago. vol. 9 p. 230. and vol. 1 p. 832.

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