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Water Pollution Treatments, 2004.
An explanation of the various methods of water pollution treatment.
2,678 words (approx. 10.7 pages), 2 sources, MLA, $ 80.95
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Abstract
This paper explains that there are are two major types of water pollution treatment: physical and chemical. The paper goes on to explain the various methods of physical treatment, including filtration and air- or steam-stripping. Chemical treatments are for killing microbes in the case of bacterial pollution, but they may be used for altering the chemical makeup of the water to render it less harmful in the case of chemical pollution.
Contents
Three Major Problems
Sediments
From the Paper
"Chemical treatments, generally, are for killing microbes in the case of bacterial pollution, but they may be used for altering the chemical makeup of the water to render it less harmful in the case of chemical pollution. Often, this sort of treatment is used to remove metal compounds from the water. Various materials such as dissolved iron or aluminum salts may be added to help the material to be removed either float or settle, again, depending on how it is to be ultimately removed.
Often, organic chemicals in water can be chemically destroyed by adding ozone or hydrogen peroxide. The ozone may also kill harmful bacterial, or chlorine may be added to do this. But of course, excess chlorine itself is harmful to aquatic life, so sulfur dioxide may then need to be added to make the ?pure? water safe for discharge. Finally, chemicals may be added to water in a treatment system to help create thicker ?sludge? so that the remaining water may be more easily removed."
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The Biochemistry of Lead Poisoning, 2003.
A look at the chemical mechanisms and biological effects of lead poisoning.
1,395 words (approx. 5.6 pages), 9 sources, MLA, $ 46.95
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Abstract
This paper describes lead poisoning, focusing on the chemical processes that take place as lead (II) displaces zinc (II) from ALAD and inhibits hemoglobin synthesis. The technical details of the inorganic and biochemical processes at play are explored and discussed, as well as the mechanisms of various lead poisoning therapeutic strategies. This paper also contains several referenced illustrations and figures.
From the Paper
"The protein ALAD, also know as porphobilinogen, is crucial in heme biosynthesis (2). ALAD, a ZnII metalloenzyme, consists of A and B subunits each of which contain a zinc atom when functional. The functionality of the A and B sites has been determined experimentally by displacement of zinc. When magnesium displaces zinc at the A site ALAD is marginally active. Furthermore, when magnesium replaces the zinc in the B site no change in the activity of the enzyme is observed (3). Thus the A site is key to the activity of the enzyme. However, when PbII displaces the active ZnII ion present in the A- site, the enzyme is rendered useless."
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Ionic Liquids, 2004.
Provides information about ionic liquids and their unique properties.
4,075 words (approx. 16.3 pages), 20 sources, MLA, $ 109.95
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Abstract
This work provides information on the properties of ionic liquids and explores how these unique properties can be used to conduct experiments that would not be possible without ionic liquids. The paper also examines the future potential of ionic liquids.
From the Paper
"One of the principal driving forces for research in this area is the need to find replacements typical solvents because they are environmentally damaging. This is because they are used in large amounts and they are volatile. Ionic liquids are different from conventional liquids. They are not composed of molecules, polar like water or acetone, or even non-polar like benzene. These liquids are composed of ions. This class of compounds came into being since the 1980s. Since these are liquids, they have the potential to behave as solvents. Which means that potentially there are a million possible solvents that can be created. By combining different anions and cations, it is possible to create a huge library of different ionic liquids each with specific properties. There are at best, 300 organic solvents that are in use in chemical and pharmaceutical industry, today."
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Magnesium Chloride, 2004.
A discussion of the pros and cons of the use of magnesium chloride as a de-icing agent.
1,228 words (approx. 4.9 pages), 6 sources, MLA, $ 41.95
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Abstract
This paper discusses how magnesium chloride has become the de-icer of choice in snowy regions such as Colorado and how supporters of the product claim that magnesium chloride is an environmentally safer option for de-icing than some of its predecessors, namely, sodium chloride. It examines how the use of magnesium chloride in liquid and modified cold-pressed form has been shown to be highly effective as a tool for de-icing in Colorado. It also looks at how supporters of the use of magnesium chloride in Colorado have stated that the de-icer has proven beneficial to the environment, while others claim the use of magnesium chloride has been shown to possibly increase electrical outages and pole fires, as well as corrosion.
From the Paper
"Another environmental issue facing Coloradoans resulting from the use of magnesium chloride is corrosion. The use of sodium chloride or rock salt in the past presented a much greater problem in this respect. Magnesium chloride however, is also by nature corrosive; however proponents of its use point out those chemical agents are added to it to minimize the corrosive effects (Pavek, 2002). Highway departments in the state of Colorado have noticed that the use of magnesium chloride as a de-icer has reduced much of the major corrosion on trucks and equipment, as well as steel enforced bridges compared to sodium chloride (Pavek, 2002). However, some reports are also indicating that aluminum components and electrical components in their vehicles are actually showing increased evidence of corrosion at a more rapid rate (Pavek, 2002)."
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Napalm, 2004.
An analysis of the impact of napalm on the 20th century.
1,158 words (approx. 4.6 pages), 2 sources, MLA, $ 39.95
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Abstract
This paper discusses how napalm, a chemical made by thickening gasoline with the aluminium salt of naphthenic and palmitic acid, was first developed in the United States during World War II and was used in the Korean War and then the Vietnam War. In particular, it examines how its use in the Vietnam War has had the most impact on the 20th century. It looks at how the widespread use of napalm contributed to ideas on the strategies of war and how the impact of napalm in the Vietnam War changed how the public viewed the war, which led to changes in the way the public was viewed in a war situation.
From the Paper
"The first impact of Napalm is the effect it has had on the strategies of war. One text titled The American Way of War: A History of United States Military Strategy and Policy, describes America?s approach to war as always being an attempt to reach total war (Weigley). This means not just fighting the forces of the opposing country, but fighting the country itself to cause their surrender. In more modern times, the recent war on Iraq can be given as an example, where American forces do not only fight against the soldiers of Iraq but bomb heavily to limit their ability to fight. With this approach, the goal is to maximize damage to the opposing country so they surrender quickly and the damage to American forces is minimized. If this approach is what America was attempting, Napalm became a way of achieving it in the Vietnam War."
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Gilbert Newton Lewis, 2003.
Discusses the scientist's contributions to the field of chemistry.
675 words (approx. 2.7 pages), 2 sources, $ 23.95
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Abstract
Discusses Lewis's original work in thermodynamics and valence theory, his academic background and career as a faculty member at MIT and UC Berkeley, his scientific research and theories of electrons bonding in pairs.
From the Paper
"Scientist Gilbert Newton Lewis' reputation lies in his extensive contributions to the field of chemistry. Lewis was born in Weymouth, Massachusetts on October 23, 1875. He was schooled at home by his parents in his early years, and at age 14, entered the..."
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Lead Halides, 1998.
A paper analyzing the physical and chemical properties of the lead (II) and lead (IV) halide compounds. Comparisons between compounds and applications are also discussed.
5,644 words (approx. 22.6 pages), 28 sources, APA, $ 136.95
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Abstract
After a brief historical introduction to lead compounds, it explains what +2 and +4 cations are and examines their uses. The physical and chemical properties of the lead (II) halides are also discussed, with mention of "mixed" halides (e.g., PbFCl).
Outline
An Introduction to Lead
General Lead Dihalide Trends
Mixed Lead Halides
Lead Chloride
Lead Bromide
Lead Iodide
Lead Fluoride
Lead Tetrahalides
Lead Tetrafluoride
Lead Tetrachloride
Possible Lead Halide Application
From the Paper
"Lead, located at the bottom of group IVA on the periodic table is well known for being a massive (atomic mass is 207.2 amu) and dense element. The density characteristics associated with lead arise from its rather compact structure despite its large size. This occurs in accordance to the periodic trend that atom size decreases as one moves left to right across a period. This trend, in conjunction with the massive properties found among the period six elements, accounts for the elements ranging from osmium to lead in that row being the densest (osmium does have the largest density) known to exist."
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Current and Future Trends and Applications in Nanotechnology, 2003.
A comprehensive review of the relevant literature to develop a better understanding of the emerging technology of nanotechnology.
2,287 words (approx. 9.1 pages), 13 sources, MLA, $ 70.95
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Abstract
This paper provides an insight into nanotechnology, an anticipated manufacturing technology that is intended to provide thorough, inexpensive control of the structure of matter through the manipulation of individual atoms. Topics discussed include the definition of nanotechnology, the ultimate goals, and potential hazards of the technology, as well as the companies, both privately and publicly owned, that are involved in the field. It looks at some of the products of nanotechnology and describes how nanotechnology can be used in our daily lives. It also discusses the role the government currently plays in funding research into nanotechnology applications. A summary of the research is provided in the conclusion.
From the Paper
"The term, ?nanotechnology,? was proposed by K. Eric Drexler. The Institute of Nanotechnology advises that nanotechnology can best be considered as a ?catch-all? phrase used to describe activities at the level of atoms and molecules that have applications in real world settings. A nanometer is a billionth of a meter (about 1/80,000 of the diameter of a human hair, or 10 times the diameter of a hydrogen atom) (Nanotechnology ? What Is It?, 2002). Nanomaterials are defined as particles having a size in the range of 1-100 nanometers that exhibit unique physical and electrochemical properties, thereby enabling the manufacture of stronger, harder, more wear-resistant materials."
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Dark Energy, 2003.
An overview of dark energy, the equation of state, and theories of universe expansion.
1,153 words (approx. 4.6 pages), 7 sources, MLA, $ 39.95
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Abstract
This paper describes dark energy, or anti-gravity, and debates theories of universe expansion, touching on Einstein's theory of relativity and cosmological constant. It also talks about the equation of state of the universe and its impact on universe expansion or contraction. It looks at how there are many theories about dark energy from the quintessence theory and the topological defect theory to the cosmological constant theory. It explains that, by analyzing the equation of state of this energy and evaluating current theories, scientists can construe a plausible theory for the fate of the universe.
From the Paper
"Physicists started negotiating and theorizing about the possibility of a dark energy around the turn of the century. One generally un-disproved theory from that time is that which relates the equation of state to the ?cosmological constant?. The cosmological constant (often called lambda) was proposed by Einstein in 1917 to make the universe unchanging in his equations (5). He was generally unsure of this idea, and rejected this theory shortly after it was determined that the universe is perpetually growing. However, his idea of a cosmological constant is currently applied to the universe in a slightly different way, setting the equation of state constant (5)(4). The current theories of dark energy date back to 1998 when supernovae were discovered to be dimmer than expected."
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Fragile X Syndrome, 2003.
An overview of the genetic disease, Fragile X Syndrome.
3,634 words (approx. 14.5 pages), 16 sources, MLA, $ 101.95
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Abstract
This paper examines Fragile X syndrome, also known as Martin-Bell syndrome, one of the most frequently inherited forms/causes of mental retardation. It looks at how the disorder is derived from a genetically inherited, single-gene mutation and how individuals who have Fragile X syndrome have symptoms that are resultant from a mutated gene on the X chromosome. It provides a short introduction, the genetics behind the disease, the mechanisms of the protein production and lack of therapy, diagnosis and symptoms.
From the Paper
"The cause of Fragile X all boils down to a change in a single gene: an alteration in the Fragile X Mental Retardation 1 (FMR1) gene. The mutation inactivates the FMR1 gene, which in turn interferes with the process involved in regulating FMRP protein content. This gene is located on the X chromosome, hence the name Fragile X syndrome. Current research indicates that the FMRP protein assists in cellular communication.3 The sex chromosome alleles for males and females are XY and XX, respectively. This establishes an understanding that Fragile X syndrome, involving the X chromosome, is a sex-linked trait. Since males and females contain either one or two X chromosomes, either can pass on the mutated gene to their offspring."
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The Mitsunobu Reaction, 2003.
An analysis of the chemical reaction known as the mitsunobu reaction.
1,228 words (approx. 4.9 pages), 17 sources, APA, $ 41.95
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Abstract
The mitsunobu reaction, discovered in 1967, involves the stereospecific reaction of an alcohol and a carboxylic acid in the presence of triphenylphosphine and diethyl azodicarboxylate (DEAD) to give an ester. This paper provides an overview of this chemical reaction and presents explanations via numerous diagrams and figures.
From the Paper
"In 1976, it was found that the formation of nitriles is also easily reached when cyanide is used as a nucleophile under Mitsunobu conditions.10 Recently, however, acetone cyanohydrin has been used as a source of hydrogen cyanide for this reaction (see figure 7). With a comparable yield and a less toxic reagent, acetone cyanohydrin is a suitable replacement for HCN.11 In this system, similar to other Mitsunobu systems, sterically hindered secondary alcohols tend to give poor yields."
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Epilepsy, 2002.
An overview of the disorder of epilepsy.
2,732 words (approx. 10.9 pages), 10 sources, MLA, $ 81.95
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Abstract
This paper looks at epilepsy and discusses the different types, symptoms, medication and social impacts as well as its treatment and aftercare. It includes basic understanding of the pathophysiology of the disease process and how drug actions and chemicals in the brain thought to contribute to the disease.
Outline
Disease Classification
Normal? Physiology and the Effects of the Disease
Treatment for the Disease
Patient Care
From the Paper
"The symptoms of Epilepsy, in my opinion and using the aforementioned evidence, definitely reflect the effects of the disease on the ?normal? physiological functioning of the body. The chaotic, unregulated neuronal discharge in the cortex seems to have, from a simplistic point of view, a direct and visible correlation with the chaotic events, muscular spasm and loss of involuntary functions e.g., Breathing, bladder control or swallowing. The complexities of diagnosis and detection of the areas of brain cortex responsible for the discharge are made somewhat easier by the use of EEG, this also simplifies diagnosis of each individual as well as identifying which strain they may have. Although Monton (1985) does state that EEG has its limitations and therefore requires clinical assessment to be used in conjunction with EEG for effective and accurate investigation and diagnosis."
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