| Papers [61-72] of 299 :: [Page 6 of 25] | | Go to page : <— 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 —> | |
|
|
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
»
Click here to show/hide summary
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:..."
| |
|
Love, 2002.
An essay on the chemistry that creates the emotion of love.
950 words (approx. 3.8 pages), 5 sources, MLA, $ 33.95
»
Click here to show/hide summary
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?."
| |
|
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
»
Click here to show/hide summary
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)."
| |
|
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
»
Click here to show/hide summary
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")."
| |
|
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
»
Click here to show/hide summary
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."
| |
|
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
»
Click here to show/hide summary
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."
| |
|
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
»
Click here to show/hide summary
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."
| |
|
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
»
Click here to show/hide summary
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."
| |
|
Polymers, 2002.
A look at the uses of polymers and biological macromolecules.
1,810 words (approx. 7.2 pages), 19 sources, MLA, $ 58.95
»
Click here to show/hide summary
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."
| |
|
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
»
Click here to show/hide summary
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."
| |
|
Naloxone and Heroin Addiction, 2006.
This paper discusses the use of naloxone to treat heroin overdose and heroin addiction.
2,414 words (approx. 9.7 pages), 13 sources, APA, $ 73.95
»
Click here to show/hide summary
Abstract
In this article, the writer notes that heroin use is a problem plaguing countries all over the world. One of the most common and successful ways to combat heroin use is with pharmacological measures. The writer points out that naloxone, a narcotic antagonist, is used to reverse the effects of a heroin overdose. In 2002 it was approved in a combination tablet with buprenorphine for the treatment of heroin addiction. The writer discusses that the approval of the combination buprenorphine/naloxone tablet means that more nurses working in an outpatient setting will be administering naloxone to patients seeking help for heroin and opiate abuse. The writer them emphasizes the importance of explaining the indications and possible side effects of any drugs administered to patients, and to know the proper procedures to take should a patient misuse the medication. The writer concludes that hopefully, as the medical community becomes more aware of the problems associated with drug use and dependence, we will be able to come up with better solutions to solving the problem.
From the Paper
"In a study done by Cantwell et al., paramedics assessed patients for respiratory status, concurrent drug intoxication, and evaluated the patient according to the Glasgow Coma Scale. Overdose victims were more likely to receive less than the standard dose of naloxone with each single increase in number of breaths. With an increasing Glasgow Coma Scale score, patients were more likely to receive less than the standard dose of naloxone. Patients with concurrent alcohol intoxication were more likely to receive greater than the standard dose of naloxone. It is thought that alcohol combined with heroin causes greater CNS depression than that produced by heroin alone. The trend towards older patients, and male patients receiving higher doses was also seen. The study suggests that patients with a higher level of consciousness and respiratory rate require a smaller dose of naloxone to return to a normal state than those patients with a lower respiratory rate and decreased level of consciousness."
| |
|
Coliphages, 2007.
Looks at an experiment to isolate coliphages from sewage.
1,570 words (approx. 6.3 pages), 9 sources, APA, $ 51.95
»
Click here to show/hide summary
Abstract
This paper explains that virtually all bacteria strains have viruses specific to them. The paper then describes an experiment that takes coliphages from sewage and, after enrichment and filtration processes, exposes the E.Coli R10 strain to the phages to obtain the phage specific to the strain. The paper further explains that the bacteria strains are grown on agar plates in the presence of coliphages, and strains W3104-A on plates K12 and W3104 and R12-B on plate K12 developed resistance. The paper then reports that the W3104-A strain is further tested and retains its resistance.
Table of Contents:
Abstract
Introduction
Materials and Method
Isolation and Enrichment of Coliphage from Raw Sewage
Filtration of Coliphage Mixtures
Dilution and Plaque Preparation of R10A and R10B E. Coli Strains
Mutation and Isolation of Phage-Resistant E. Coli Strains
Sensitivity of Phage-Resistant Mutants to Bacteriophages
Results
Discussion
Table: Colonies of Bacterial Strains Response to Coliphages
From the Paper
"Bacteria have the ability to develop resistance to viruses [6], so as it can be expected some strains (namely W3104-A and R12-B) developed phage-resistant colonies. It is known that certain genetic elements called "episomes" are instrumental in creating phage-resistance in E. Coli strains such as K12 [8]. As indicated in table 1, there were numerous contaminations; this was certainly due to many of the unfiltered cultures that were used. This was done because of time constraints and shortage or missing supplies in the lab."
|
|
|
