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Effects of Alcohol on Taste and Smell, 2000.
A fefination of alcohol and analysis of its impact on two senses.
1,125 words (approx. 4.5 pages), 7 sources, $ 39.95
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From the Paper
"Effects of Alcohol on Taste and Smell
Introduction
The purpose of this paper is to examine the effects of alcohol on people's perception of taste and smell. The paper begins with a brief description of the impacting factor (alcohol) and how it operates. It then goes on to discuss the affects of alcohol at the first and second levels of perception of taste and smell. The final section of the paper presents a several conclusions formulated on the basis of the reviewed literature.
The Impacting Factor: Alcohol
Definition and Operation
Alcohol is the term used to refer to any class of organic compounds characterized by one or more hydroxyl (OH) groups attached to..."
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Reducing Porosity in Brass, 2000.
A technical examination of methods of reduction, history, phase diagrams, density, hardening and more.
2,925 words (approx. 11.7 pages), 14 sources, $ 103.95
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Abstract
Matrix management is associated with a matrix organizational form. A matrix form of organization is an organizational structure with two or more (a) channels of command, (b) lines of budget authority, (c) sources of performance reward, and (d) so forth.
From the Paper
"Methods of Reducing Porosity In Brass
Introduction. Matrix management is associated with a matrix organizational form. A matrix form of organization is an organizational structure with two or more (a) channels of command, (b) lines of budget authority, (c) sources of performance reward, and (d) so forth. A lack of maximal density, or some porosity, must exist in the metals' lattice structure or must be introduced in the alloying process. Explored here are methods metallurgists may use to minimize porosity in brass.
Brass. A useful alloy of two metals, copper and zinc (9:166), brass has been formed for cultural uses and ornamentation since the 13th century BC (1:9). The term, brass, indicates any of an infinite possible set of mixes of "copper-..."
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Beta Carotene, 1999.
Examines the structure, chemistry and biological activity, focusing on antioxidant and anti-carcinogenic properties in animal systems.
1,575 words (approx. 6.3 pages), 25 sources, $ 55.95
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Abstract
Examines the structure, chemistry and biological activity, focusing on antioxidant and anti-carcinogenic properties in animal systems.
From the Paper
"Beta Carotene
The carotenoids as a group, and specifically the beta carotenes, are known to serve a variety of functions in living cells. Presented here is an overview of the structure, chemistry, and biological activity of beta carotene, with emphasis on its capacity as an antioxidant and anti-carcinogen in animal systems.
Beta carotene is a member of a class of pigments called carotenoids, which occur naturally in plants and are found as well in animals. A precursor of vitamin A, also called provitamin A, it is found as an orange-red pigment in terrestrial plants, algae and some marine mammals. After purification, it appears as ruby-red crystals, easily oxidized on contact with air, with MP 184 degrees, MW 536.44. It is insoluble in water, slightly soluble in alcohol, soluble in chloroform, carbon disulfide, ether and benzene. Its ..."
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Carbohydrates, Lipids & Proteins, 1997.
Examines role of these carbon compounds in human diet & nutrition, related to organic chemistry.
2,025 words (approx. 8.1 pages), 8 sources, $ 71.95
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From the Paper
"Organic chemistry is the study of carbon compounds. Carbon compounds are central to the existence of every life form on earth. They make up the muscles of animals and human, the stems and leaves of plants, the molecules that transfer genetic information, protective clothing, hydrocarbons that breakdown to provide the energy for transport, and perhaps most important the food products for nutrition. In this paper, aspects of the relationship between organic chemistry and the three major food groups - carbohydrates, lipids and proteins - are explored.
An enormous amount of time and energy is spent preparing and eating the food that sustains and maintains human health. Consuming food is pleasurable and culturally significant, as exemplified by the holiday meals at Christmas, Hanukah, and the celebrations at wedding receptions. As a result of the abundance.."
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Friedrich Wohler, 1996.
Career, major concepts & discoveries of 19th Cent. German chemist.
2,250 words (approx. 9.0 pages), 15 sources, $ 79.95
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"Many fundamental concepts in chemistry can be traced back to Friedrich Wohler. A mild-mannered scientist, Wohler's discoveries revolutionized the understanding of organic chemicals. His artificial synthesis of urea eventually led to the overthrow of the theory of vitalism. In addition, Wohler contributed to ideas on isomerism and organic radicals. His work has ultimately had a great influence on the development of many fields of scientific endeavor.
A quiet, gentle person, Friedrich Wohler combined his "passion for chemistry" with a "great love of the open air, the beauties of nature and of all living things" (Findlay, 1965, pp. 323-324). Indeed, that branch of chemistry dealing with compounds of carbon is widely considered to have been started by..."
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Polyvinyl Chloride, 1996.
Development of this plastic & uses in industry & home, physical properties, manufacture, environmental issues, polymerization, costs.
2,025 words (approx. 8.1 pages), 7 sources, $ 71.95
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"Compared to most other materials, plastics have been introduced relatively recently. In fact, many of the major developments in plastics technology have occurred over the last 50 years. One plastic that currently finds widespread application in the construction industry is polyvinyl chloride (PVC). Although PVC has been around for over 100 years, it wasn't developed commercially until about the 1930s. The pure resin consists of a linear polymer. The compound's chlorine atoms cause considerable inter-chain attraction. Hence, in its pure state, the material is hard and rigid. With modifying agents, however, PVC can be softened to produce an entire array of flexible products. Indeed, the substance may be the most versatile of the plastics. PVC is currently found in cable..."
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Chemical Synthesis of Peptides, 1996.
Discovery, process, history, techniques, properties, side effects.
2,250 words (approx. 9.0 pages), 11 sources, $ 79.95
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From the Paper
"Peptides were first synthesized around the turn of the century. During the following decades, the compounds found many applications. At present, both solid and liquid phase methods may be used to chemically formulate peptides. The formation of a peptide bond requires both activation and protection. Although these processes have a long history, researchers continue to search for better coupling reagents and improved protecting group strategies.
Curtius (1881) and Fischer (1902) were the first to synthesize simple peptide derivatives (2:1-8). About that time, Hofmeister (1902) and Fischer (1906) additionally recognized that proteins actually consist of amino acids linked together by amide bonds. Subsequent peptide research generally involved the..."
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Empirical Formula, 2002.
A laboratory report using an empirical formula to find a compound created inside the crucible.
1,000 words (approx. 4.0 pages), 0 sources, APA, $ 35.95
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Abstract
he paper is written in the form of a laboratory report. The purpose of the experiment was to use an empirical formula in order to find a compound which has been created inside a crucible. The paper shows the procedure in which the experiment was done as well as its outcome. Flow charts, tabulated results and mathematical calculations are also included in the paper.
From the Paper
"The importance of safety precautions is extremely important in trying to maintain a safe and healthful research environment. When working with all extremely hot metals with your hands, gloves should be worn at all times. The temperatures of these metals or "hot objects" absorb heat and could cause damage to the skin if touched. Without the use of gloves, hands can be severely burnt. One mistake or foolish act could cause much pain and suffering to students in the laboratory. People who do not handle hot objects carefully can get their nerves burnt off on their finger tips and could possibly never feel again. It is not worth taking a risk of not using gloves when applicable. Everyone wants to be safe in the laboratory so it is important to be aware and cautious. A safe laboratory is a safe life."
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Nitric Oxide, 2001.
Technical discussion of the discovery of how nitric oxide acts in the human body. Its value in treating cardiovascular disease.
2,700 words (approx. 10.8 pages), 13 sources, $ 95.95
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From the Paper
"In 1998, three American scientists were awarded the Nobel prize for Physiology and Medicine for their discovery that nitric oxide, a common gas in air pollution, transmits signals within the human body (Maugh, 1998). The discovery was hailed as one of the most important in the history of cardiovascular medicine, and was predicted to lead the way to treating high blood pressure and heart attacks. It led to the development of Viagra, to a new treatment for newborns with dangerously high blood pressure in their lungs, and to drugs for the treatment of shock.
"The signaling function of nitric oxide influences virtually every organ system in the body. The discovery that nitric acid produced by one cell could alter the function of other cells is an entirely new principle for signaling in biological systems...."
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Quality Initiatives in the Pharmaceutical Industry, 2002.
An analysis of the enormous demands placed on the pharmaceutical industry by the public and government agencies.
2,980 words (approx. 11.9 pages), 7 sources, MLA, $ 87.95
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Abstract
This paper describes the pharmaceutical industry's role as one of the largest contributors to economic growth in the United States. It illustrates the tremendous pressure the pharmaceutical industry is under, to meet the increasing demands for their product and maintain the quality standards of the regulatory agencies. The writer explains why it is in the best interest of the industry to attempt to maintain the high standards placed on them.
From the Paper
"According the US Business Reporter (2002), annual spending on prescription drugs is expanding at close to 14% on and annual basis. Several companies and drugs have led this increase, particularly Warner-Lambert's Lipitor, Eli Lilly's Zyprexa, Monsanto/ Pfizer's Celebrex, and Merck's Vioxx (US Business Reporter, 2002). The same article notes that the pharmaceutical industry typically operates on a 14-15% profit margin. This makes the pharmaceutical industry one of the largest contributors to economic growth in the Untied States."
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The Effects of a Neurotoxin on the Mammalian Brain, 2000.
A paper which studies the effects of the Superfund Neurotoxin Methylazoxymethanol (MAM) on brain dendritic spine density in long hooded Evans Rats Rattus norvegicus.
2,100 words (approx. 8.4 pages), 11 sources, APA, $ 65.95
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Abstract
The paper shows that in the study of structural development in the brain there have been several proposed biomarkers for quantifying brain plasticity. These include but are not limited to cortical thickness, dendritic length and branching, expression of neuronal proteins, and the presence of DNA adducts. The paper discusses the theory that a measure of brain plasticity emerging late in embryonic development will be a very sensitive biomarker for detecting subtle damage suffered by brain cells during earlier stages of brain development not detectable by other means. The paper shows that to test this, the effects of a neurotoxin on the late developing dendritic spines were studied. A significant decrease in spine density was observed as the neurotoxin, methylazoxymethanol, increased. The author of the paper shows how the implications are widespread in the study of neuro-degenerative disease.
From the Paper
"Fifty years ago, Donald Hebb demonstrated that the conditions under which laboratory rats were housed could significantly affect their performance in a variety of complex spatial tasks later in life (1). The complex environment rearing paradigm has been valuable in assessing plasticity of a variety of brain components including cerebral cortical microvasculature, astrocyetic morphology, dentritic branching patterns, synaptic number, and synaptic structure are all affected by complex environment rearing (2). It has been suggested that multiple synaptic contacts (spines) may play a role in the spread of the additive effect of learning known as potentiation, among neighboring unstimulated neurons. A lack of these spines and their connection with boutons of neighboring neurons could then result in a decrease in the capacity for learning. Some recent work has indicated that the presence of multiple synaptic contacts may be altered by experience. Most of this research has focused on structural changes in the hippocampus. Dendrtic spines show great variability in structure and connectivity, both within and across brain structures, including 10-fold differences in length and diameter as well as variations in the number of branches and spines per dendrite."
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Hemoglobin, Oxygen Transport and Nitric Oxide, 2001.
This paper presents electron paramagnetic resonance and oxygen binding studies of -nitrosyl hemoglobin - a novel oxygen carrier having NO (Nitric Oxide) assisted allosteric functions.
1,345 words (approx. 5.4 pages), 3 sources, APA, $ 45.95
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Abstract
This paper shows that Nitric Oxide (NO) is a very popular compound to investigate in the scientific community today. It is physiologically ubiquitous as a potent vasodilator, neurotransmitter, and immuno-active agent at low concentrations and it is produced and recycled in the respiratory tract to regulate the airway. This paper discusses in detail the mechanism behind oxygen binding and release by hemoglobin as it relates NO bound to the Hemoglobin. The oxygen affinity dynamics of native Hemoglobin and nitrosylated Hb are compared. The research also reveals that although NO has a much higher affinity than oxygen or carbon monoxide for Hemoglobin, NO behaves differently than these other ligands and is not as toxic to normal Hb oxygen binding as previously assumed.
From the Paper
"Small, unicellular aerobic organisms can obtain oxygen required for metabolism by simple diffusion from the environment. Most multicellular organisms have too great a surface area and many cells not in contact with the environment. They require circulatory systems that transport oxygen from gas-exchange organs to other tissues. In vertebrates, oxygen is bound to molecules of Hemoglobin (Hb) or transport in Red Blood Cells. Mammalian Hemoglobin is a tetramer, consisting of four polypeptide chains; two a and two b. Six ligands are coordinated to the ferrous iron, with the ligands in octahedral geometry around the metal cation (figure 1). In aqueous solution, free heme does not does not reversibly bind oxygen. Instead the Fe(II) is rapidly oxidized to Fe(III) when it gives up an electron to oxygen. The quaternary structure of hemoglobin prevents formal transfer of an electron and allows it to reversibly bind O2. Positively charged amino acid residues stabilize to negatively charged diatomic oxygen without an ionic bond. Hemoglobin unbound to oxygen is called deoxyhemoglobin and has a low affinity for oxygen. Once one oxygen molecule binds to the Fe, the proximal Histadine (figure 1) moves closer to the porphyrin ring because the Fe is now bound to six ligands instead of five. This disrupts the stabilizing ions that interact with Hb. The remaining Heme groups have an increased affinity for Oxygen. In addition to this positive cooperatively of binding, allosteric interactions regulate the binding and release of oxygen by Hb (Horton, 1996)."
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Solid Propulsion, 2000.
An essay outlining the history and modern use of solid propulsion in comparison to other types of propulsion.
1,145 words (approx. 4.6 pages), 1 source, MLA, $ 39.95
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Abstract
The following paper examines the history of solid propulsion and black powder and discusses how it was used. It also looks at the advantages and disadvantages of solid propulsion in relation to its liquid counterparts.
From the Paper
"The first solid propulsion engines were invented by the Chinese early in the 13th century in use of fireworks. These homemade rockets were propelled by black powder. The first recorded military use was in 1232 in a military siege where the powder propelled rockets were used to set fire to tents. It wasn't until years later around the early 15th century when they started becoming used in Europe and equipped with a payload. Gunpowder started being used as it burned slower than black powder. The two have same the same ingredients but in different proportions. A large step forward was when the solid propulsion rockets were used to carry rope from distressed ships to shore in stormy conditions. The sailors would use the rope as a lifeline in their rowboats. However this relied on the fact that the shore could only be as far away as the longest rope."
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Peter Debye, 2002.
A discussion on the life, achievements and research of Peter Debye, winner of 'The Nobel Prize' in Chemistry 1936.
750 words (approx. 3.0 pages), 4 sources, MLA, $ 26.95
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Abstract
The following paper discusses what Peter Debye was awarded the Nobel Prize for and lists the other awards he received throughout his lifetime. This paper also looks at Debye's early modification of a theory belonging to Einstein as well as contributions to chemistry.
From the Paper
"Peter Debye (1884-1966) was awarded The Nobel Prize in Chemistry 1936 for what the Nobel e-museum describes as his contributions to our knowledge of molecular structure through his investigations on dipole moments and on the diffraction of X-rays and electrons in gases.(Nobel e-museum) He has a chemical unit of measure named for him debye units (D) , which measures the dipole moment for polar molecules. (Chang, 308) Aside from The Nobel Prize in 1936, he received Honorary Doctorates from & Brussels and Liege; Oxford; Sofia; Maniz; Technische Hochschule, Aachen; Eidgenosissche Technische Hochschule, Switzerland; Harvard; St. Lawrence; Colgate; Notre Dame; Holy Cross; Brooklyn Polytechnic; Boston College, Providence College."
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Dimitri Mendeleev, 2002.
This paper discusses the life and contributions of Dimitri Mendeleev, the founder of the first Periodic Table of Elements.
940 words (approx. 3.8 pages), 4 sources, MLA, $ 33.95
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Abstract
This paper looks at the life-long contributions that Dimitri Mendeleev made to the field of chemistry. The author details Mendeleev's personal and professional biography including his battle against childhood disease which almost cost him his life. His family's struggle to insure that he was able to study at a prestigious university and to overcome the poverty into which he had been born influenced his drive to constantly work and succeed in his chosen field. In 1869 Mendeleev constructed the first Periodic Table of Elements. He also authored many books in the field of chemistry and predicted the discovery of many different elements, as well as weights and measure. The author also notes his many contributions to the advancement of technology in Russia.
From the Paper
Mendeleev was born in 1834 in Siberia. His family consisted of thirteen brothers and sisters, his mother and his father. The family was poor, his father eventually went deaf before he died, and yet Mendeleev's mother insisted that her youngest child further his education. He hitchhiked over 14,000 miles across Russia to Moscow, only to be turned down by the University of Moscow because he was from Siberia. His mother never gave up, and the two of them traveled to St. Petersburg where he trained and eventually became a Professor of inorganic chemistry at the University of. St. Petersburg. (Chang, 233) During his third year of study there, Mendeleev fell ill, and was bedridden for the next year. He kept up with his studies, and graduated on time, and received the medal of excellence for being first in his class. (Rumppe, Sixtus
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