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Search results 61 - 70 of 278 matching essays
- 61: Monosaccharides
- ... at the second carbon atom (ketose). The carbonyl group combines in aqueous solution with one hydroxyl group to form a cyclic compound (hemi-acetal or hemi-ketal). Monosaccharides are classified by the number of carbon atoms in the molecule; trioses have three, tetroses four, pentoses five, hexoses six, and heptoses seven. Most contain five or six. The most important pentoses include xylose, found combined as xylan in woody materials; arabinose from ... molecule previously involved in linking one sugar molecule to another, and a methylated glucose, in this case named 2,3,6 tri-O-methyl-D-glucose, forms. The linkage positions (in the example, at carbon atoms 1 and 4; the carbon atoms are numbered in the structure of the methylated glucose), which are not methylated, in a complex carbohydrate can be established by analyzing the locations (in the example, at carbon atoms 2, 3, and 6) ...
- 62: Nuke Waste
- ... manner that isolation from the biosphere is assured until they have decayed to innocuous levels. If this is not done, the world could face severe physical problems to living species living on this planet. Some atoms can disintegrate spontaneously. As they do, they emit ionizing radiation. Atoms having this property are called radioactive. By far the greatest number of uses for radioactivity in Canada relate not to the fission, but to the decay of radioactive materials - radioisotopes. These are unstable atoms that emit energy for a period of time that varies with the isotope. During this active period, while the atoms are 'decaying' to a stable state their energies can be used according to the ...
- 63: Galileo and Newton
- ... behind such. It is concerned simply with what happens and how it is happening. The philosophy of physics could extend the concepts to incorporate purpose. The world is the product of the chance concourse of atoms. Everything is comprised of atoms and it makes up the known world to which mathematical principles analyze. If there are no purposes in the universe and this fact is supported through scientific study, then there is purpose in that science ... and would probably say that his ideas are relevant and not over simplified. Form in the world is the effect of other causes in a long, scientific chain of efficient causes by the interactions of atoms. In a way Newton's cosmological ideas are better because he was able to support interactions within the universe with mathematical reasoning. He eventually came to the belief that "there is no scientific explanation ...
- 64: Nuclear Energy
- ... can be contained and used as fuel for the power. Most of this power is fueled by uranium isotopes. These isotopes are highly radioactive. The isotope catches the fast moving neutrons created by the splitting atoms, it repels the slower moving protons and electrons, then gathers the neutrons and pulls them inward. While all these atoms are flying about they smash together then split many of many times, this is when the reactor grabs and pulls in the frictional energy to be processed into electrical watts. This usually causes heat or ... can be contained and used as fuel for the power. Most of this power is fueled by uranium isotopes. These isotopes are highly radioactive. The isotope catches the fast moving neutrons created by the splitting atoms, it repels the slower moving protons and electrons, then gathers the neutrons and pulls them inward. While all these atoms are flying about they smash together then split many of many times, this is ...
- 65: Lasers 3
- ... laser started as long ago as 1905 when Albert Einstein suggested the simulated emission of light. Light sources ie. candles, florescent substances, torches, and light bulbs give of packets of energy, called photons, when their atoms are excited by energy. Einstein suggested that these atoms could be artificially stimulated to emit photons, where the light produced would be highly concentrated, bright and powerful and could be used for many tasks. Even though Einstein new the principals for building a laser ... it a strobe lamp is coiled around the core, a rod of ruby that has mirrors at its ends, one of which is only partially solid. As the strobe light flashes it excites the ruby atoms that in turn emit photons. The photons are reflected back and forth by the mirrors until they pass through the partially solid mirror. This results in brief bursts of pure red laser light that ...
- 66: Rutherford's Gold Foil Experiment
- ... consisted of Polonium in a lead box emitting alpha particles towards a gold foil. The foil was surrounded by a luminescent zinc sulfide screen to detect where the alpha particles went after contacting the gold atoms. Because of Thomson's atomic model this experiment did not seem worthwhile for it predicted all the alpha particles would go straight through the foil. Despite however unlikely it may have seemed for the alpha particles to bounce off the gold atoms, they did. Leaving Rutherford to say, "It was almost as incredible as if you fired a fifteen-inch shell at a piece of tissue paper and it came back and hit you." Soon he came ... more than one elctron at a time; therefore, all of the alpha particles should have passed straight through the gold foil. This was not the case – a notable few alpha particles reflected of the gold atoms back towards the polonium. Hence the mass of an atom must be condessed in consentrated core. Otherwise the mass of the alpha particles would be greated than any part of an atom they hit. ...
- 67: Radon
- ... 222. The shell configuration is 2,8,18,32,18,8. Radon's most stable isotope is Rn 222 with a half-life of 3.82 days. An isotope is one of two or more atoms that have the same atomic number, but have different atomic weights and mass numbers (The America Heritage Dictionary of the English Language, Third Edition, 1992). The nuclei of isotopes of the same element have the ... does not combine with other chemicals or elements. Traces of radon are normally found in the atmosphere near the ground as the result of seepage from rocks and soil. On a worldwide average, approximately 6 atoms of radon emerge from every square inch of soil each second (Dunford, 1991). Radon is also moderately soluble in water and, therefore, can be absorbed by water flowing through rock or sand. Its solubility depends ... cancer. (Dunford, 1991) As long as the atmosphere dilutes radon, the cancer is insignificant. Near ground level there is no more than about one radon atom for every 10,000,000,000,000,000,000 atoms of air. The problem is, it seeps into buildings and homes where it becomes trapped, and consequently accumulates. The EPA estimates that as many as 8 million homes may be harboring unacceptable quantities of ...
- 68: Destruction of the Ozone Layer
- ... do not dissolve in water. They do not break down in the lower atmosphere. When CFC's get to the stratosphere, The ultraviolet radiation from the sun causes them to break apart and release chlorine atoms. Then the chlorine atoms which react with ozone, start chemical cycles of ozone destruction that depletes the ozone layer ("Some Commonly Asked Questions About Ozone Depletion" 1). A single chlorine atom can break apart at least 100,000 ozone molecules ( Some Commonly Asked Questions About Ozone Depletion 1). The chlorine attaches to the oxygen atoms and breaks the ozone molecule apart (Brooks 422). A single CFC molecule stays in the atmosphere for 50-200 years ( Song 2). There are many consequences involved in the destruction of the Ozone layer. ...
- 69: Fusion
- ... their lives by lacking pressure to continue fusion and calmly fade into inert masses. This is not the case with giant class stars. After a mere 9 or 10 million years, all of the hydrogen atoms in the core have fused into helium (Figure 2.1). This causes a temporary pause to the fusion in the core, allowing gravity to compress it. This compression raises the core temperature to 170 million ... layers around the core that continue to fuse hydrogen into helium, and helium into carbon (Figure 2.3). With a mere seven years to go, the core temperature of 1.5 billion degrees, the neon atoms in the core begin to fuse into more oxygen and magnesium, giving the star an onion-like appearance, each layer being denser toward the center (Figure 2.4). With one year to go, the core ... gravity. With a tenth of a second to go, the iron core is collapsing at approximately 45,000 miles a second, packing the earth-sized core into a sphere only ten miles across. The iron atoms become so compressed that the nuclei melt together, creating enough heat to fill the core with neutrinos. The core has now reached maximum crunch, meaning it can no longer contract (Figure 2.7). The ...
- 70: Nuclear Weapons Are A Threat to All
- ... placed at opposite ends of a metal cylinder. One of the pieces has a powerful, nonnuclear explosive behind it that explodes on impact and drives the piece into the one at the other end. The atoms in the material the collide and start a chain reaction. In the implosion method a ball of either uranium or plutonium is surrounded by a large amount of nonnuclear explosive. When triggered it compresses the nuclear material, which also causes a chain reaction. Thermonuclear or fusion weapons get their destructive power from the combining of light atoms. Hydrogen, the lightest element, is used in making fusion weapons. When the atoms of the element fuse, they release a great amount of energy. The only problem is that the element must be heated to a temperature of 50 million degrees Celsius. The only way to do ...
Search results 61 - 70 of 278 matching essays
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