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Glycyglycine Experiment, 1999.
Deblocking of Benzyloxycarbonylglycylglycine to Glycylglycine.
950 words (approx. 3.8 pages), 4 sources, $ 33.95
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Abstract
This paper details the results of a chemistry experiment on the deblocking of benzyloxycarbonlyglycylglycine to glycylglycine. The production of glycylglycine 4, a peptide consisting of two glycine units, is described. The reaction of Z-Gly-Gly-OH 1, an N-carbobenzoxylated peptide was reacted with hydrogen bromide in acetic acid to produce glycylglycine 4. The purification of glycylglycine 4 was achieved through filtration to give a low yield of 13%. The experiment was successful with the product being identified as glycylglycine 4; it was identified as such through the analysis of its melting point.
From the Paper
"Z-Gly-Gly-OH 1 is a peptide composed of two gylcine residues or units. Z-Gly-Gly-OH 1 may also be referred to as a C-terminal amino acid because it has a free carboxyl group at the right end of the molecule1. Z-Gly-Gly-OH 1 is reacted with hydrogen bromide in glacial acetic acid, which results in the scission of the N-acyl substituent yielding glycylglycine 42. "
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Methane Hydrates, 2000.
A look at the threat posed by methane hydrates.
2,608 words (approx. 10.4 pages), 11 sources, $ 78.95
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From the Paper
"Methane hydrates are solid, crystalline structures that exist at low temperatures and high pressures. They are composed of a methane gas, which is encased by a water cage. Methane hydrates were discovered in the 1900's but until recently were considered a nuisance. Recently, methane hydrates have been considered as the next fuel source for the future. Some believe that there is enough methane in the form of methane hydrates to supply energy for hundreds, maybe even thousands of years. Methane hydrates may be the answer to the fossil fuel crisis. One characteristic that has not been researched to an acceptable level is the effect that methane hydrates have on global warming. By harnessing methane hydrates as a fuel we have the potential of unlocking an immense quantity of methane. Methane is twenty-one times better, than carbon dioxide, at retaining infrared energy. This trapped infrared energy intensifies the greenhouse effect also referred to as global warming. However, we may not have to directly tap into the hydrate reserves to increase global warming. We may have already, unknowingly, set this process in motion. There are significant amounts of methane hydrates trapped in permafrost. By increasing global warming, through the use of fossil fuels, we may have already destabilized the methane hydrates that were trapped in permafrost."
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Michael Addition, 2001.
Synthesis of 1-phenyl-3-phenylaminopyrrolidine-2,5-dione
1,838 words (approx. 7.4 pages), 4 sources, $ 58.95
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From the Paper
"The preparation of 1-phenyl-3-phenylaminopyrrolidine-2,5-dione 5, a fused-ring heterocycle, is described. The synthesis of maleanilic acid 3, was completed with the reaction of maleic anhydride 1 with aniline 2. The resulting product maleanilic acid 3 was reacted with acetic anhydride to produce N-phenylmaleimide 4. N-phenylmaleimide 4 was then reacted with aniline 2 to produce 1-phenyl-3-phenylaminopyrrolidine-2,5-dione 5. The purification of all three compounds maleanilic acid 3, N-phenylmaleimide 4, and 1-phenyl-3-phenylaminopyrrolidine-2,5-dione 5 was achieved through filtration. The product maleanilic acid 3 was high in yield with 84.4% being recovered. N-phenylmaleimide 4 was mediocre in yield with only 68.0% being recovered. The final product, 1-phenyl-3-phenylaminopyrrolidine-2,5-dione 5,was high in yield with 85.8% obtained. The experiment was successful with the products being identified as maleanilic acid 3, N-phenylmaleimide 4, and 1-phenyl-3-phenylaminopyrrolidine-2,5-dione 5. The compounds were identified as such through their melting points, and spectral information obtained from IR, and 1H NMR."
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Lab Report on Organic Synthesis, 2001.
2,657 words (approx. 10.6 pages), 2 sources, $ 79.95
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Abstract
This project lab explored the applications of directed ortho metalation in organic synthesis.
From the Paper
" In particular a piperidine based directing group 2, an amide, was obtained from o-toluyl chloride 1. The amide 2 was deprotonated at the ortho position with sec-BuLi and an electrophile, benzylaldehyde, was introduced. The introduction of the electrophile resulted in the addition of a benzyl alcohol group onto the deprotonated amide, resulting in the final product 3. The amide 2 was high in yield with 92.4% being recovered; however the final product 3 was low in yield with only 34.0% being recovered. The amide 2 was identified as such through spectral information obtained from IR, 1H NMR, and 13C NMR. The final product 3 was not produced as was determined through spectral information obtained from IR, and 1H NMR."
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Snow Scavenging of Atmospheric Organic Contaminants, 1998.
Analysis of a lab experiment atmospheric organic contaminants.
1,449 words (approx. 5.8 pages), 1 source, $ 48.95
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Abstract
The purpose of this experiment was to investigate the scavenging of atmospheric organic contaminants from precipitation, specifically snow and rain. The paper also determined and quantified, from scavenging, the amount of polychlorinated biphenyls and polycyclic aromatic hydrocarbons present in snow and rain. Snow scavenging of organic contaminants was being studied because little is known about this phenomenon and a large amount of precipitation, which occurs in North America, occurs in the form of snow. By studying the various precipitation the researchers were able to observe snow scavenging, the gas scavenging abilities of rain and the particle scavenging abilities of both rain and snow.
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Determination of Anion Solutions Using HPLC, 2000.
Procedure, results and discussion about a scientific experiment
1,715 words (approx. 6.9 pages), 5 sources, $ 55.95
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From the Paper
"The unknown sample L03-02 was determined for the anions fluoride, chloride, nitrite, nitrate and bromide. The anions were determined using HPLC. The type of HPLC used was ion-exchange chromatography. The sensitivity of ion-exchange chromatography has made precise measurements at the ppm level for many inorganic anions commonplace3. Ion-exchange chromatography was chosen as the method for this lab because of its' sensitivity and its' ability to determine as many as 10 inorganic ions in a single measurement at better than an ion per minute3."
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The Life and Work of Marie Curie, 2000.
A look at her life and impact in the fields of physics and chemistry.
1,530 words (approx. 6.1 pages), 10 sources, $ 50.95
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Abstract
This paper is a biography of Marie Curie's life, as well as her work and impact in the fields of physics and chemistry. It also pays particular notice to radioactivity. The paper is based on the strong theme that ?nothing in life is to be feared, only understood,? a quote attributed to Marie Curie herself.
From the Paper
"Marie?s childhood was not a perfect one by any means. She was the fifth child in her family, and soon after she was born, both of her parents lost their jobs as teachers. Despite losing their jobs, Marie?s parents still managed to instill into their daughter the value of education, and had taught her to read by age 4. Her parents also instilled in Marie a sense of duty. This, combined with the family?s economic circumstances lead Marie to lead ?the most Spartan of lives.? [?Marie Curie?, Minist?re des Affaires ?trang?res de la R?publique Fran?aise, 1.] Marie?s childhood continued to be harsh, as she had to deal with the deaths of both her mother, and one of her sisters by age 11. This only served to create a sense of ?agnosticism that would later bolster her faith in science,? [?Marie Curie?, Minist?re des Affaires ?trang?res de la R?publique Fran?aise, 1.] however. Despite the many setbacks that seemed to litter her childhood, Marie persevered. In spite of the long hours she spent helping cook meals for the boarders that her family had taken in, at age 15, Marie won a medal for excellence at her high school, where the examinations where administered in Russian. She dreamed of someday becoming a scientist?something that was not socially-acceptable for women to do in Poland in the 1880?s."
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Marijuana and its Effects, 2001.
An examination of marijuana, its chemistry, its actions in the brain, and its psychological effects.
848 words (approx. 3.4 pages), 10 sources, $ 30.95
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From the Paper
"THC has a range of physiological and psychological effects on the body. Typically, it produces a mild euphoric intoxication, a sense of well-being, alterations in sense of space and time. Quite likely, THC reduces anxiety and relaxes your tension while it intensifies your sense of sound, touch ,or taste, which often stimulates your appetite. It is suspected that THC has something to do with the Lateral Hypothalamus that control the appetite. For this reason, marijuana is employed as an appetite stimulant for patients with serious illnesses such as AIDS or terminal cancer who need to eat in order to survive. In addition, marijuana is also medically beneficial for pain relief, control of nausea and the treatment of asthma and glaucoma."
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The Genetic Disorder Phenylketonuria (PKU), 2001.
A brief examination of this disorder, which affects brain development. Includes an examination of the genetic components and illustrations.
850 words (approx. 3.4 pages), 7 sources, $ 30.95
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From the Paper
"Phenylketonuria (PKU) is a genetic disorder characterized by an inability of the body to utilize one of the constituents of a normal diet- phenylalanine (PHE), which is one of the essential amino acids. Essential amino acids cannot be synthesized within the body. It means that they have to be taken in from the foods. PHE is found in all protein foods such as meat, eggs, fish, milk, cheese, and so forth. "
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An overview of Potassium, 2000.
The uses and importance of potassium, including its uses in the human body.
860 words (approx. 3.4 pages), 3 sources, $ 30.95
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Abstract
This paper discusses the elements uses, abundance, discovery, atomic mass and characteristics of potassium, as well as some common forms and how the body uses it.
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A Study of the Medical Aspects of Pathological Intoxication, 1994.
1,090 words (approx. 4.4 pages), 6 sources, $ 38.95
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Abstract
This paper examines the nature and scope of pathological intoxication, also referred to as alcohol idiosyncratic intoxication. The paper concludes that the insidious nature of pathological intoxication far exceeds other forms of alcoholism due to its nature and effect upon the individual.
From the Paper
"This disorder is usually defined as a mental aberration, involving severe behavioral alterations when the affected individual consumes alcohol (Mendelson 215), yet those affected with pathological intoxication behave in a manner most unlike their normal self, usually resulting in aggression (DSM-III 132). This alteration in behavior is directly associated with the amount of ethanol ingested, for in regular drinkers, small amounts of ethanol produce no ill effects except for mild intoxication, but in individuals with PI, small amounts can trigger bizarre behavioral changes. Following the ingestion of a single drink, the affected individual becomes very intoxicated which results in assault or belligerent behavior."
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An Explanation of the Principles and Uses of Supercritical Fluid Chromatography, 2001.
A look at the many advantages of this technique, and in what applications it can be used.
2,310 words (approx. 9.2 pages), 3 sources, $ 71.95
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From the Paper
"Although the properties of supercritical fluids were know, it was not until 1958 when Lovelock suggested that a supercritical fluid can be used as a mobile phase in chromatography. Now, supercritical fluid chromatography (SFC) is widely used in extraction, fraction, and chromatography. SFC has many advantages over other chromatography methods. It allows one to separate many substances that cannot be analyzed by gas chromatography. Its applicability is limited by volatility and thermal properties of many organic compounds. Although less volatile compounds can be analyzed by high performance liquid chromatography, very long analysis time and very small column diameters are needed in order to achieve good separations due to the limitations of solute diffusion in the mobile phase. SFC is able to overcome these difficulties and allows high-resolution separation at low temperatures with short analysis times."
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The Scientific Revolution According to Thomas Kuhn, 1999.
The paper questions whether science moves forward in a cumulative and progressive manner, or if it moves forward in leaps and bounds?
1,440 words (approx. 5.8 pages), 3 sources, $ 47.95
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From the Paper
"Science can be broadly defined as the development of knowledge about the physical world. The history of science is the explanation of the development of this knowledge. Science is often viewed as cumulative and progressive by its nature. Such views, however, can have profound implications because not all scientists or theorists follow the cumulative view. Scientists use both deductive and inductive reasoning to hypothesize the possibility of a useful theory. They also seem to be able to decide or discover more easily which theories are false rather than which theories are true. While the proving or disproving of scientific theory plays a vital part in the growth of science and scientific inquiry, the way that the actual progress or creation and discovery of new ideas and paradigms of thought is at the center of scientific research. Does science move forward in a cumulative and progressive manner or does it move forward in leaps and bounds? "
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Wood Verses Plastic Cutting Boards, 2000.
A scientific analysis of the different ways to sterilize wood versus plastic cutting boards and the different advantages.
1,854 words (approx. 7.4 pages), 6 sources, $ 59.95
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Abstract
Written in the style of a scientific review article for a journal, this paper compares the sanitation of wood versus plastic cutting boards. One of the main points emphasized is the ability of each material to prevent disease and bacteria.
From the Paper
"Every home, restaurant, and commercial food processing area needs a cutting and chopping surface. The materials these surfaces are made of have been under scrutiny as possible sources of foodborne illness. Most cutting board safety issues relate to cross-contamination, which results from processing ready-to-eat, non-cooked items (such as a salad) on a board previously used to cut animal products (1,6). The residue from the animal product inoculates the non-cooked food with pathogenic microflora. This residue, called biofilm, can be made of any number of food products, but the most common sources of pathogenic bacteria result from a biofilm deposit of chicken or beef extract (?juice?)."
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Visualization: Molecular Structure and the VSEPR Theory, 2000.
An exploration of the concepts of this theory and how to use balloons to build geometric models of several types of molecules.
850 words (approx. 3.4 pages), 1 source, $ 30.95
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From the Paper
" This theory has since become what we now know as the valence-shell electron-pair repulsion model (VSEPR), which states that the geometric arrangement of electron pairs around a central atom are the result of electrostatic repulsion between electron pairs. The basic principle of this is that repulsion between electrons in bonding pairs and lone pairs causes them to remain as far apart as geometrically possible. Thus, the arrangement that a molecule ultimately assumes is the one that best minimizes repulsion."
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