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Organic Chemistry, 2002.
An explanation of the makeup of different hydrocarbons.
1,719 words (approx. 6.9 pages), 6 sources, MLA, £ 32.95
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Abstract
This paper discusses the differences between organic and inorganic chemistry and provides a brief insight into organic chemistry and the family of the hydrocarbons. It looks at how the salient point to remember in the formation of compounds (everything else flows from there) that drives chemical processes is the need to complete the valence or the atomic shell of each element?s inherent instability. It shows how inorganic and organic chemistry are the results of variable approaches to solving the instability and how this then results in the formation of the stable compounds that the world we live in and the universe at large need to survive.
From the Paper
"The arrangement of the four electrons around the carbon lend it a tetrahedral (equal on four sides in three dimensions) geometry. The simplest organic compound is methane (inflammable gas found in sewers and coal mines) where a single carbon atom is covalently linked to four hydrogen atoms. In this way, each hydrogen atom can claim two electrons needed to complete its shell (its own and one from carbon). The four carbon electrons and one each from the four hydrogen atoms complete its shell of eight. If one considers a chain of carbon atoms linked together carbon to carbon (C-C) with associated carbon to hydrogen (C-H) bonds, an organic molecule is formed. These compounds are straight chains, rings, or chains with cross- links and branches."
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Biologically-Active Natural Products, 2002.
This paper discusses the isolation and structural determination of biologically-active natural products by using various chromatographic techniques.
8,750 words (approx. 35.0 pages), 35 sources, APA, £ 107.95
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Abstract
This paper explains that nature acts as a pharmacy, offering us products, from the forest pharmacy and the pharmacy below water, with which we can heal ourselves: For example, aspirin, quinine, cyclosporins, and penicillin. This paper details the techniques that are available to researchers, to collect samples of natural products from the wild in a systematic manner, to extract compounds from these samples, to isolate the biologically-active compounds within these extracts, to characterize the biologically-active compounds chemically in terms of their structure, to evaluate the biologically-active compounds biologically, to determine potentially useful therapeutic effects and finally the methodology necessary to take these compounds to clinical trial. The author stresses the importance of finding new and more effective drugs to fight against bacterial infections and cancer. Outline.
Table of Contents
Introduction
Nature?s Pharmacopeia.
The Isolation of Biologically-Active Compounds and their Extraction Identification: Techniques
Introduction
Chemical Extraction
Biological Evaluation
Chemical Analysis
Chromatography
Solid Phase Extraction
Paper Chromatography
Thin Layer Chromatography
Flash Chromatography
High Performance Liquid Chromatography
Central Counter Current Chromatography
Determining the Chemical Structure of Compounds Isolated by Chromatography
Nuclear Magnetic Resonance
Mass Spectrometry
Drug Development
Examples of the Isolation and Identification
An Example of Extraction, Isolation and Chemical Characterization of Biologically-Active Compounds from Larch Wood
Biologically-active Compounds from Marine Organisms
What Compounds Have Been Isolated From Marine Organisms?
Biologically-Active Anti-Cancer Compounds ? Testing for Human Safety
Conclusion
From the Paper
"Chromatography is the process whereby two or more compounds or ions are separated through the distribution of the compound or ion between two phases, one that is mobile and the other which is stationary. These two phases can be of any combination: liquid-liquid, solid-solid, solid-liquid or gas-liquid, gas-gas, or gas-solid. There are many specific techniques for chromatography, some of which will be described below, and all follow the same basic principles. All forms of chromatography involve a rapid and dynamic equilibrium of molecules between the two phases, either free ? mobile - or absorbed ? stationary. Molecules will constantly move back and forth between the free and absorbed states, with millions of molecules absorbing and desorbing every second. The equilibrium between these states depends on three factors: the polarity and size of the molecule, the polarity of the stationary phase, and the polarity of the solvent. Thus, three different variables can be changed in chromatography, which can change the equilibrium between the stationary and mobile phases: this allows one to choose mobile and stationary phases that will separate just about any combination of compounds."
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Isolation of Esherichia coli Bacteriophages from Sewage, 2002.
This paper is a laboratory experiment using sewer water, which contains a large concentration of E.coli, to locate the bacteriophage to be isolated.
1,215 words (approx. 4.9 pages), 2 sources, £ 24.95
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Abstract
This paper reports on an experiment in which, using sewage water to locate the E.coli bacteriophage, the bacteriophage was isolated from the original culture and placed in an enriched medium to grow and reproduce. The author continues that each one of the plaques represents a viron from the original culture, and, by counting the plaques, they were able to determine the concentration of bacteriophages in the culture. The author reports that findings among the different lab groups differed significantly, but this could be explained by the fact that the experiments were performed on separate days a week apart.
Table of Contents
Abstract
Introduction
Materials and Methods
Results
Discussion
From the Paper
"E.coli was grown for 48 hrs in TSB tubes at 37degrees C by the lab assistant. (Sewage from the Cheney Sewage Works.) The sewage was then centrifuged and the bacteria containing portion was filtered using a 100 mL filter apparatus. I picked up my E.coli and filtered sewage from the lab assistant. Next, I gathered 7 plates of triptocase soy agar. These were labeled 1x10^-3 to 1x10^-9 and placed into the incubator to bring their temperature up to that of the bacteria/phage solution to be added later. 9 Eppendorf tubes were labeled 1x10^-1 to 1x10^-9, these were then set aside. Sterile saline was then gathered and using a Beckman autopipetter. I transferred 900 uL of sterile saline into each Eppendorf tube."
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The Periodic Table, 2002.
A brief look at the history and components of the chemistry periodic table. Includes a chart.
1,052 words (approx. 4.2 pages), 3 sources, MLA, £ 21.95
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Abstract
This paper begins by providing background information about the history and development of the periodic table. It mentions the first component discovered and the main people involved in developing and compiling the table in the mid-1800s. The paper then analyzes different families or groups in the periodic table - hydrogen, metals, noble gases, non metals and transition metals.
From the Paper
"The organization of the modern periodic table is perhaps one of the most significant tasks undertaken in chemistry. From this chart, we see the common properties of certain elements as well as glimpse into the atomic structure of the atom. It is the purpose of this paper to introduce the periodic table and briefly discuss its parts."
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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, £ 47.95
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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, £ 19.95
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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, £ 17.95
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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, £ 41.95
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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, £ 14.95
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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, £ 19.95
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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, £ 42.95
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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, £ 17.95
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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, £ 34.95
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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, £ 23.95
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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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