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Alumina, 2002.
This paper discusses the background history, chemical and physical properties, manufacturing process (the Bayer process) and applications of Alumina.
2,675 words (approx. 10.7 pages), 9 sources, $ 80.95
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Abstract
This paper discusses Alumina or Aluminum Oxide, the only oxide formed by the metal aluminum, which occurs in nature as the minerals corundum, diaspore, gibbsite and most commonly as bauxite, which is an impure form of gibbsite. The author submits that its industrial and commercial use in the modern times took off after the development of the Bayer process, which made possible the wide-scale, low cost production of the material.
Table of Contents
Introduction
Background Information: History of Alumina
Initial Manufacture of Alumina
Manufacture of Aluminum & the Bayer Process
New Natural Forms of Alumina
Properties of Alumina
Mechanical Properties
Thermal Properties
Electrical Properties
Structure of Crystalline Alumina
Alumina (Aluminum Oxide) Structure
Structure of Liquid Alumina
Applications of Alumina
Ceramics
As an Insulating Material
Electronics
Mechanical Ceramics
Military Uses
Bio Medical
Chemical Ceramics
Enameling
Refractory Uses
Chemical Industry
Catalysts, Fillers, and the Glass industry
The Bayer Process
Grinding of Bauxite
Digestion of Bauxite
Settling and washing of Residues
Crystallization of Hydrates
Calcination of Hydrate
Conclusion
From the Paper
"Fused alumina (the substance produced after being melted and re-crystallized) is identical in chemical and physical properties with natural corundum. It is a very hard material and its hardness is exceeded only by diamond and a few synthetic substances such as carborundum, and silicon carbide. This property of alumina lends itself for use as an abrasive material. Another useful property of the material is its high melting point, i.e., above 2000?C (3632?F), which makes it useful as a refractory and as linings of special furnaces. The mechanical, chemical, and electrical properties of Alumina (99.7% purity) often used in the ceramic industry are depicted in the following tables:..."
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Love, 2002.
An essay on the chemistry that creates the emotion of love.
950 words (approx. 3.8 pages), 5 sources, MLA, $ 33.95
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Abstract
This paper explores the concept that love is the emotion, which ascribes to a specific physical and physiological set of body changes. It describes that loves occurs in a person whose pheromones most closely match or please that of another person. The paper answers the basic question, "what is love?" through a series of scientific texts and explains the effects that love-the-emotion has on the physical body.
From the Paper
"What, then, are the ?chemicals? which tell the body love is in the air? The first one, released all through a partner?s love-life, is known as the ?cuddle? hormone. It is called Oxytocin and is released by the hypothalamus gland during childbirth as well as in (smaller) quantities when one spends time with one?s loved one. During sexual climax, more oxytocin is released into the bloodstream. Scientists believe that oxytocin helps encourage bonding among adults. The second is a chemical cocktail known as PEA. This stands for Phenylethylamine and is what causes one to fall in ?love?."
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Alcohol and the Brain, 2002.
A paper which looks at the effect of alcohol on the brain.
817 words (approx. 3.3 pages), 5 sources, MLA, $ 29.95
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Abstract
The effects of alochol abuse on the unborn child, on society and on relationships are quite wellknown, but the fact that alcohol can affect the brain is a fact that is less known. The paper shows that in fact alcohol stops the cortex from serving its role in integrating cognitive processes, resulting in disorganized thinking and motor control difficulties. The paper examines research that shows that individuals with a history of chronic alcohol abuse had significantly smaller brains than non alcoholic individuals. Finally, the paper concludes that continuous research on the subject may help combat alcoholism in the future.
From the Paper
"The actions of several neurotransmitters are significantly affected by the actions of alcohol. Gamma-aminobutyric acid (GABA) is one of the most prevalent neurotransmitters in the human brain, and alcohol is clearly linked to affects on the GABAergic system in the human brain. For example, the symptoms of alcohol withdrawal are reduced by blocking the activity of the neurotransmitter by the use of drugs that are well known to block GABA receptors. This evidence suggests that alcohol may play an important role in the biological underpinnings of human alcoholism. Researchers have also noted that tolerance and dependence on alcohol can be explained by the neuropharmacological effect of chronic alcohol use (Brain & Mind Magazine)."
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A Discussion on Biology, 2002.
This paper defines several biological terms in an easy-to-understand manner.
2,329 words (approx. 9.3 pages), 11 sources, $ 71.95
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Abstract
A discussion between family members that gives a lesson in biology and defines several aspects of biology such as vegetarianism, protein, vitamin B12, cladistics, tetrapods, and antisense technology. Because this colloquial paper is written in the style of a story being told to the lay person, the reader is able to easily understand the bioligical concepts.
From the Paper
""I'm being more efficient," Sadie said. "The 10% rule of ecology says that only 10% of the available energy stored in a food can be used by the next level of the ecosystem. So plants can use only 10% of the energy sent by the sun, and we can use only 10% of the energy stored by plants when we eat them, or 1% of what comes from the sun. Eating meat cuts the percentage to one-tenth of 1%. Too inefficient. That's why I eat only plants" ("Vegetarianism"). Sadie nodded her head wisely.
"She's right, you know." David was a graduate student in molecular biology. He knew that sort of stuff backward and forward. Uncle Eldridge looked a little startled.
"I learned that in class, too," I added.
"But what about protein? How do you get enough protein?" Aunt Sally looked worried.
"There are a lot of sources of protein besides meat. The need for protein is based on getting both essential and non-essential amino acids from your food," Sadie explained. "It can be from complete protein foods, like meat or fish or chicken, that include all the amino acids. But non-complete protein foods are just called that because they don't include every amino acid. So you just have to combine them to get all the amino acids you need."
"Will you be able to get all your amino acids today without the turkey?" Mom asked.
"Probably," Sadie said. "The beans, the potatoes, the walnuts, and the corn in the cornbread probably include all the essential amino acids between them." ("Protein")."
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The Atoms in My Hand, 2002.
An insight into atoms - what they are and where they come from.
715 words (approx. 2.9 pages), 3 sources, MLA, $ 25.95
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Abstract
The paper gives a brief insight into atoms from the beginning of recognition of their existence by the ancient Greeks, to the ability today to create man-made ones. It discusses the chemical composition of atoms and how scientists can now predict their behavior with great accuracy.
From the Paper
"According to existing theories and experimental results, the Big Bang took place about 12,000-15,000 million years ago. Within the first three minutes of the existence of the Universe, the light elements originated. Atoms came along after about 300,000 years and the stars and galaxies originated during the first million years. However, it took a while for humans to recognize atoms, although they were right before their eyes."
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Acid Rain, 2002.
A discussion of the concept of acid rain and its environmental dangers.
945 words (approx. 3.8 pages), 3 sources, MLA, $ 33.95
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Abstract
This paper provides a definition of "acid rain" and how it is formed. It looks at the dangers of acid rain and the damage it is doing to the environment. It briefly examines options and programs that can be performed to reduce acid rain.
From the Paper
"The term ?acid rain? is a little misleading. Rain is naturally acidic, from both carbon dioxide in the air and absorption of chlorine from the ocean (Gordon, 2002). All compounds can be measured for acidity or alkalinity on a Ph scale ranging from 0 ? 14, with anything below 7 showing at least slight acidity. Rain is judged ?acid? when its Ph falls below 5. (Gordon, 2002) Environmental scientists are concerned because in some parts of our country, the level of acidity in rain and snow has increased beyond its normal levels. This has had a serious impact in several areas, including our forests in the northeast and many of our most valued monuments."
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Medicinal and Recreational Purposes of Drugs, 2002.
A study of alcohol, marijuana, cocaine, morphine and heroin, outlining their medicinal and recreational purposes.
2,353 words (approx. 9.4 pages), 16 sources, APA, $ 72.95
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Abstract
This paper discusses five drugs (alcohol, marijuana, cocaine, morphine and heroin) commonly used for recreation and examines their medical effects. The writer describes each drug, its legal status and illustrates its uses as medical agents. The paper explains that the complex interaction of social acceptance, proven benefits as a medical agent, and potential side effects (including addiction) all played an important role in determining if a specific drug is used as a medical agent in today?s health care system.
From the Paper
"Alcohol, marijuana, cocaine, morphine and heroin have all been used extensively as medical agents. All five drugs have also been used extensively for recreational purposes. As a result of their known adverse effects, marijuana, cocaine, morphine and heroin were all made illegal. However, alcohol remains legal. There is a resurgence of interest in the medical effects of marijuana, cocaine and morphine."
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Dry?Cell Batteries, 2002.
A technical research report on the definition of dry-cell batteries and their kinetic make-up.
835 words (approx. 3.3 pages), 2 sources, APA, $ 29.95
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Abstract
The paper discusses dry-cell batteries which were invented as an alternative to higher leaking, long lasting batteries. Today?s advanced electronics are demanding more battery power and it is not unusual for a highly developed electronic item to go through two or three sets of batteries in a day. The paper shows that as technology advances, the stronger the battery demand and this brought about the invention of the dry-cell battery. The purpose of this technical research is to define dry cell batteries, their kinetic make-up, and how are they recycled.
From the Paper
"Recycling batteries saves the environment and ensures proper disposal. There are many programs which assist in helping individuals learns how to recycle batteries. There is one program called ?Charge Up To Recycle? which educates people on the recycling process, and the companies that recycle batteries. The objective of this program is to make everyone aware of the available services and encourage them to participate in recycling of the batteries. There are some battery recycle facilities that charge a small fee for used up batteries, but most of these facilities will take the batteries free of charge. The purpose of the battery manufacturers is to get everyone involved in recycling old batteries. Recycling batteries can be very beneficial to the air, eliminating lots of air pollution."
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Polymers, 2002.
A look at the uses of polymers and biological macromolecules.
1,810 words (approx. 7.2 pages), 19 sources, MLA, $ 58.95
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Abstract
An examination of the Van der Waal equation of state in a Virial expansion and a look at how Polymers are being used today in every walk of life. This paper shows how polymers are well-defined aggregates of very simple organic molecules. It defines these matters and looks at their uses in biochemistry.
From the Paper
"From thermodynamics and the kinetic theory of gases, the Pressure of an ideal gas is described as sum of the transfer of collision energy of gas molecules on the walls of the container. The inter-atomic interactions depend upon the density of the system. Inter-particle interactions, primarily attractive forces, reduce the overall pressure of the system. This interaction is called internal pressure. By rewriting the Van der Waal equation of state in a Virial expansion, we obtain an equation for Pressure p: (Atkins, 1987)
p = RT/(Vm ? b) - a/Vm2
a/Vm2 is the internal pressure of the gas; a and b are constants for each gas and Vm is the molar volume of the gas, R is the Gas Constant."
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Boron Composite Structures in Aviation, 2001.
This paper studies the past and future use of boron composite structures in aviation.
1,190 words (approx. 4.8 pages), 11 sources, APA, $ 40.95
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Abstract
This paper details a brief history of boron composites from its earliest applications to recent developments. It studies the application of boron in composite epoxies and fibers and the use of these materials in airframe manufacturing. It includes figures showing usage of Boron composite. It concludes that boron has been very successful in aircraft manufacturing if the costs can be brought down.
From the Paper
"Compounds of boron, most notably from unfinished borax ore, known as Tincal, were exported from Tibet in olden times. Historically, boron has been used for refining gold and silver in Arabia, ceramic glazes in China, and embalming in Egypt.
"Boric acid, a mild antiseptic, was isolated in the laboratory by chemistry professor William Homberg in 1720. Sir Humphrey Davy, a British chemist, and two French chemists, Joseph Gay-Lussac and Baron Louis Th?nard, discovered the element, boron, in 1808 concurrently. However, it took another 155 years before science turned its focus from borax to boron, and began to reveal the secrets of this mysterious and valuable element."
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Optimum pH and Temperature for Enzyme Efficiency, 2009.
A description of an experiment carried out to measure the optimum environmental conditions for the enzyme alpha-amylase.
757 words (approx. 3.0 pages), 2 sources, APA, $ 26.95
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Abstract
This paper describes proteins which are enzymes, and an experiment carried out to measure the optimal pH and temperature of the reaction between the enzyme alpha-amylase and starch. The author explains that enzymes are natural biochemical catalysts that selectively speed up chemical reactions. These enzymes can be greatly affected by the pH and temperature of the environment they are in and have optimal conditions in which they work most efficiently. Using light spectrometry and a variety of pH levels and temperatures to find a maximum efficiency of this protein, the author recorded absorbance levels to show the optimal pH and temperature of this reaction.
Outline
Abstract
Materials and Methods
Discussion
From the Paper
"The experiment was done with variations in two different environmental factors, pH and temperature, and separate data were taken for each. For both experiments, a blank was prepared using 5mL distilled water and 0.1mL of I2KI indicator placed in a cuvette. This cuvette was used to set the spectrophotometer to zero absorbance with the wavelength set at 560nm. 0.1 mL of I2KI indicator was placed in 11 cuvettes for each experiment. For the temperature variation, six different water baths were made at 15, 30, 45, 55, 60, and 70 C. In each water bath a solution of 35mL starch and 35mL distilled water was mixed in an Erlenmeyer flask and allowed sufficient time to reach the given temperature."
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Poison in a Pretty Bottle, 2009.
A discussion of the extent to which cosmetics contain toxic ingredients.
1,420 words (approx. 5.7 pages), 8 sources, MLA, $ 47.95
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Abstract
This paper looks at some of the chemicals contained in cosmetics and the dangers they pose to our health. The author explains that the U.S. Food and Drug Administration is extremely lax in their requirements with respect to cosmetic products and does not even have the authority to take a harmful product off the market unless the manufacturer voluntarily recalls that product. The author describes the use and effects of some of the most harmful ingredients, such as phthalates, lead and 1,4-Dioxane. The paper concludes that until the FDA approaches the EU's elevated health standards, American consumers are better off doing their own research before buying such products, and making an extra effort to make their concerns known to the government and demand changes.
From the Paper
"In comparison with the European Union's Cosmetic Directive, the FDA is failing miserably in keeping up with personal care safety standards. Currently, the FDA has only prohibited 9 toxic ingredients from being included in cosmetics, while the EU has banned over 1,000. To aggravate the issue, the Cosmetics Ingredients Review, an organization that works with the FDA, "reviewed just 11 percent of the 10,500 cosmetic ingredients cataloged by the FDA, [while the] 89 percent of ingredients that remain unassessed are used in more than 99 percent of all products on the market" (Inspired Living)."
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Synthesis and Action of the Grignard Reagent, 2008.
A discussion of an experiment that looks at synthesis and the action of the Grignard reagent.
912 words (approx. 3.6 pages), 6 sources, MLA, $ 32.95
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Abstract
This paper discusses an experiment in which a Grignard reagent was synthesized and used to perform its unique function - nucleophilic addition to create a carbon-carbon bond. The paper describes the materials and methods used in the experiment. It then presents the results in a table and discusses the findings of the experiment.
Table of Contents:
Introduction
Materials and Methods
Results
Discussion
Appendix
From the Paper
"Bis(diphenylmethyl) ether was more likely to form than any other side product because it is a result of nucleophilic substitution, which was the most likely mechanism to occur under the experimental conditions (Mazid and Palmer, 1975). The formation of biphenyl (as a result of self-coupling) was not possible during the synthesis of the Grignard reagent because during the Grignard reaction, coupling is avoided and precautions are taking to insure it does not occur. In order for the two carbons to couple, like in the alkylation by an acetylide ion (Wade, 433-445), the halide has to leave. However, the halide is an important component of any Grignard reagent, and if displaced by self-coupling (via nucleophilic substitution), the intended reaction could not occur. In other words, after the joining of the two equivalent alkyl groups, no further alkylationis possible, since the Grignard reagent would be destroyed (Wade, 433-445)."
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Identification of Unknown Organic Compounds, 2008.
A presentation of the methods and results of an experiment to identify unknown organic compounds.
1,072 words (approx. 4.3 pages), 5 sources, MLA, $ 37.95
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Abstract
This paper presents and examines an experiment that identifies two unknown compounds based on their solubility, reactions with various organic and inorganic molecules and the melting point of certain synthesized derivatives containing the unknown. It describes the methods of the experiment and then presents and discusses the results obtained.
Table of Contents:
Introduction
Materials and Methods
Results
Discussion
From the Paper
"The final step in the identification process was to make an acetamide derivative and its melting point to discover the primary amine (Organic Chemistry Lab Manual, 48-65). However, the recrystallization process did not yield any crystals, so the melting point of the actual unknown was measured. At 108-110oC, it would indicate 3-nitroaniline, which has a melting point of 113oC in literature (ChemIDplus Advanced). In addition, it does have a high molecular weight, 138.14 g/mol (ChemIDplus Advanced), as the solubility of its sulfonamide salt indicated (Organic Chemistry Lab Manual, 48-65). Finally, it is the only primary amine that is a yellow crystalline solid at room temperature (International Programme on Chemical Safety)."
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Alcohols, Ethers, Aldehydes and Ketones, 2008.
An examination of the results of an experiment that compares alcohols, ethers, aldehydes and ketones.
1,386 words (approx. 5.5 pages), 5 sources, MLA, $ 46.95
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Abstract
This paper discusses an experiment that introduced several methods of differentiating between several types of organic compounds containing oxygen in their functional groups. Specifically, the experiment compares alcohols, ethers, aldehydes and ketones. The paper presents the results in a table and discusses them. Several figures are also presented.
Table of Contents:
Introduction
Materials and Methods
Results
Discussion
From the Paper
"In this test, the rate of reaction is dependant upon the degree of substitution. This is because the Lucas reagent creates conditions that favour the SN1 mechanism, and therefore, the most substituted carbocation intermediate will react the fastest. Therefore, when the alcohol group is on a tri-substituted carbon, like in 3-methyl-1-buten-3-ol and 2-methyl-2-butanol, the reaction will be the fastest. In addition, 3-methyl-1-buten-3-ol contains a double bond, which enables resonance stabilization of the carbocation intermediate. 2-methyl-2-butanol lacks this feature, and is therefore, slightly slower. Since the alcohol group is on a di-substituted carbon in 3-methyl-2-butanol, the reaction will be even slower. 3-methyl-1-butanol will not even react since its alcohol group is on a mono-substituted carbon."
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