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Catalytic Antibodies, 1995.
This paper discusses catalytic antibodies: Definition, process involving chemistry and immunology, problems and applications.
1,350 words (approx. 5.4 pages), 8 sources, $ 47.95
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From the Paper
"Catalytic antibodies are derived from chemically stable hapten which mimic reactions' transitional states. Through their binding energy, the antibodies are able to increase both the specificity and rate of the reactions. These techniques were initially applied to chemical processes which did not require catalysts. Various investigators, for example, have used catalytic antibodies to facilitate the Claisen rearrangement. More recent research, however, has focused on disfavored reactions (i.e., ring closure transformations). One day these methods may find widespread application in various fields of scientific endeavor. "
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Calcium-Dependent Atpase, 1995.
This paper discusses analytic techniques for understandingthe processes of Calcium-Dependent Atpase involving common eukaryotic enzyme.
2,925 words (approx. 11.7 pages), 11 sources, $ 103.95
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"A common eukaryotic enzyme, calcium-dependent ATPase has been extensively investigated. The ion-transport enzyme uses energy derived from the hydrolysis of adenosine triphosphate (ATP) to move Ca2+ against a concentration gradient. Innumerable techniques have been applied to Ca2+-ATPase analyses. These have included proteolytic, genetic, immunologic, and molecular approaches.
Calcium-dependent ATPase was first isolated in 1970 (3:696-700). This heterogenous family of enzymes can be broadly subdivided into two separate groups. The plasma membrane Ca2+-ATPase occurs in most eukaryotic tissues. This 140-kDa enzyme binds calmodulin and is stimulated by calcium ion (10:285-297). Although it may be derived from plants, yeasts, or, for example,
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Free Radicals, 1994.
This paper discusses free radicals, chemical compounds with an unpaired electron and their role as biochemical mediators and cause of diseases.
2,025 words (approx. 8.1 pages), 8 sources, $ 71.95
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"Only relatively recently has importance of free radicals gained widespread acceptance. This may be the result of the compounds' inherent intangibility. They are generally short.lived, hard to work with, and difficult to study. Regardless though, it is now confirmed that low levels of free radicals are normally produced as a consequence of metabolic activity. It is also known that the compounds serve as potent biochemical mediators in a number of physiologic roles. However, their great catabolic potential does require focus and control. Unrestrained free radicals can significantly damage biological systems. To counteract such deleterious effects, defenses have evolved. Under normal circumstances, animal cells typically maintain an intricate balance between the generation of free
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Teaching Chemistry, 1994.
This paper discusses ways to make teaching chemistry exciting, relevant and comprehensible: Theory and experimental applications.
1,575 words (approx. 6.3 pages), 6 sources, $ 55.95
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"The teaching of chemistry should constitute more than facts about chemicals and their methods of bonding. What is needed even more is to teach the fundamental ways of thinking used by chemists, for if the student can master these modes of thought, he or she will be better able to understand chemistry and any facts that are to be taught later. To teach this mode of though, a strategy is needed that will help the student understand the issues involved. The teaching of chemistry os often delayed until the alter grades, but this is not a good approach given that by the time the student reaches those grades, his or her mode of thought is set and is difficult to change. Children should be guided to understand the sciences beginning in the early grades so they will be better prepared for more advanced scientific knowledge later. An examination of some of the modes ... "
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Ammonia, 1994.
Discovery, characteristics, toxicity, dangers and its use in agriculture & industry.
1,350 words (approx. 5.4 pages), 11 sources, $ 47.95
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" Ammonia
The chemical, ammonia, has broad application in both industry and agriculture. During the last century, considerable quantities of this compound have been produced. Although ammonia itself is not inherently poisonous, severe exposures may cause airway destruction and burns of the skin. Moreover, under certain conditions, ammonia can burn or explode. Given the chemical's widespread occurrence, the management of ammonia merits careful analysis.
It remains a relatively unknown fact that the first synthesis of ammonia ranks as one of the most important discoveries in the history of science. In 1840, Justus von Leibeg concluded that a significant component of plant nutrition was "fixed" nitrogen. At that time, fixed nitrogen was available.."
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Alchemy, 1993.
A look at the origins and development, the impact on the science of chemistry, theories, leaders, techniques, goals and the role of Sir Isaac Newton.
3,375 words (approx. 13.5 pages), 30 sources, $ 119.95
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"The purpose of this research is to examine the origins and development of alchemy, from the earliest stages of its practice and through the transitions it made from being a pseudo-science toward becoming a major foundation of the harder science of chemistry. As appropriate, reference will be made to those features of alchemy that appear to have survived the transition and continued to exercise an influence on the environment of scientific research.
The origins of alchemy can be traced as far back as the Greeks and the Hellenistic period, if the historiography of the scientific community is to be taken as a guide. It seems important to include Aristotle in any understanding of the reach of alchemy for the reason that the residue of philosophical and scientific environment of intellectual discipline attributed to..."
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Arsenic, 1993.
A look at the nature and types of carcinogenic dangers from contaminated water and workplaces.
1,350 words (approx. 5.4 pages), 13 sources, $ 47.95
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"Arsenic: A Human Carcinogen
Arsenic has always had an evil reputation. Its use as a homicidal and suicidal agent is widely known. In addition, more recently, its potential for causing harm in the environment is being realized. Abundant studies establish a relationship between arsenic and certain types of cancer. As a contaminant in drinking water, it poses a significant threat to human health.
The alchemists' symbol for arsenic is a coiled serpent (Levander et al., 1977, p. 1). The chemical is famous for its poisonous attributes. Less well.known, however, is the fact that arsenic has also been used as a therapeutic "tonic." For hundreds of years, patients received arsenic for conditions ranging from acute infections to epilepsy, and asthma (Bickley & Papa, 1989, p. 378). Furthermore, both inorganic and organic..."
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Chemistry, 1992.
An overview of the major concerns of this scientific field including chemical change, classification of matter, laws, gases, atomic mass, formulas, periodic table, ionic compounds, acids and bases.
3,600 words (approx. 14.4 pages), 3 sources, $ 127.95
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"Chemistry is a branch of science that is used to explain and reveal the composition, structure, and properties of substances and to demonstrate the changes that they can undergo. For example, interaction with other materials can cause substances to acquire different properties, such as a change in physical form. Therefore, a large part of chemistry is observation--before, during, and after change takes place. There are three fields of study in chemistry--organic, inorganic, and physical chemistry. Organic chemistry deals with the study of compounds made up from carbon forms, such as those found in living beings. Inorganic chemistry covers compounds not found in plants or animals and therefore classed as inorganic (noncarbon compounds). Physical chemistry addresses the actions of chemistry that are resolved using the laws of physics."
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History of Chemistry, 1991.
An overview from Ancient Greece (nature of matter) to the 20th century (atomic discoveries).
1,575 words (approx. 6.3 pages), 2 sources, $ 55.95
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"The history of chemistry involves a journey from its magical and mythological origin to the highly complex and analytical science that it is today. Chemistry, the science which explains the composition of matter and the changes that different forms of matter undergo, did not gain much momentum until the seventeenth century. Prior to the 1600s, the study of chemistry languished in a pre-scientific period, suffering from some prominent misconceptions and untenable theories. Advances made in the nineteenth and twentieth centuries have brought chemistry to such an advanced state that we are able to examine the composition of material on an atomic, and even a sub-atomic level.
Beginning with the use of fire, humans have observed the transformation of matter. Fire burns wood to produce ash, and meat becomes cooked over flame. These changes, known to..."
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Fire Retardants, 1991.
This paper discusses fire retardants: Chemical formulations, advantages and disadvantages of different types.
1,350 words (approx. 5.4 pages), 4 sources, $ 47.95
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"Fire is a lethal force that can easily escape control. In structures, it often starts in the building's furnishings and then ignites the structure itself. One of the keys to fire control, therefore, is to prevent the fire from spreading throughout a building via its contents, usually by depriving the fire of the fuel it needs to grow. It is this premise of flame suppression that underlies most research into flame retardants.
There are several fire types and "hazard situations": nonflaming/smoldering fires, early or small flaming fires, and fully developed large-scale (called post-flashover) fires. Nonflaming/smoldering fires can start from overheating of vulnerable substances or can be self-sustaining over a long ... "
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Freon, 1991.
This paper discusses Freon: Chemical properties, uses and environmental dangers of this chlorofluorocarbon.
1,575 words (approx. 6.3 pages), 8 sources, $ 55.95
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"Freon is the commonly known trade name used by E.I. du Pont de Nemours and Company to refer to a certain class of chemical compounds known as "refrigerants." Refrigerants are synthetic compounds called chlorofluorocarbons that are used to perform a variety of basic jobs. Chlorofluorocarbons generally are considered very stable, safe compounds; they are colorless, odorless, nontoxic, noncorrosive, and nonflammable. They vaporize at 300 degrees. Unfortunately, however, although they are considered nonreactive (or inert), they are believed to undergo destructive reactions when they reach the upper atmosphere that damage the ozone layer.
To make Freons, carbon tetrachloride (CCl4) or chloroform (CHCl3) is combined with anhydrous hydrogen fluoride (HF) and a suitable catalyst. The Freon results when a chlorine or a ... "
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Synthetic Methods for Enantiomers of Drugs, 2002.
An analysis of the various methods of producing pure enatiomeric drugs.
1,650 words (approx. 6.6 pages), 9 sources, APA, $ 53.95
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Abstract
This paper discusses how ever since the ?Thalidomide? incidence last century there has been an ever-increasing amount of resources injected into optical isomeric research and in attaining pure enantiomeric products. It shows how due to different stereochemical characteristics, different isomers will have different interactions with biological receptors in the body, giving rise to different actions. A resultant undesirable effect is therefore inherently possible upon the consumption of chiral drugs, for that reason it is imperative that the end drug mixture is as entiomerically pure as possible. It describes the 3 basic methodologies for single enantiomers: chirality pool, kinetic resolution and asymmetric synthesis and examines the basis of and the techniques of separating them.
From the Paper
"One way of the use of chirality pool molecules merely requires the maintenance of pre-existing chirality throughout a synthesis, with transformation of other parts of the molecule by formation of new chemical bonds or inter-conversion of functional groups. Otherwise, utilising chirality pool can afford a so-called ?control element? for the creation of new stereogenic centres by ?substrate-directable? reactions. Such reactions may involve complete transfer of chirality from one region to another intra-molecularly.[1]"
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