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."
This paper presents electron paramagnetic resonance and oxygen binding studies of -nitrosyl hemoglobin - a novel oxygen carrier having NO (Nitric Oxide) assisted allosteric functions.
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)."
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."
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."
Tags: protons, electrons, neutrons, quantum, physics, nucleus, atomic, number
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."
Tags: composition, data, error, knowledge, molar, percent, physics, ratio
Abstract This paper analyzes St. Johns Wort (SJW), a common herbal treatment. It offers an insight into how its constituents affect us neurologically with its primary ingredients of hypericin, hyperflorin and various flavanoids and describes how, although SJW can be used for various treatments, the main condition that it is used for is depression. It provides a comparative study of conventional anti-depressive agents and their relative side effects and shows how the demand for herbal medicines today is rising at exponential rates, with an obvious advantage such as reductions in the number of side effects. It evaluates whether herbal medicines all that they claim to be and if they contain any profound pharmacological constituents or whether they give just a placebo effect.
From the Paper "Herbal medicines are clearly mixtures of more than one active ingredient and in many instances, we are not sure which or how many constituents are pharmacologically important. Furthermore, in trying to acquire the mechanisms of action of plant extracts is often complicated even if we know the active ingredient because such extracts contain a wide range of pharmacologically active constituents that might work together to contribute to the pharmacological activity. [1] Our understanding is further dinted if the molecular basis of the disease under investigation is not well understood."
From the Paper "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 ... "
From the Paper "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 ... "
From the Paper " 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.."
From the Paper "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 ... "
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. "
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"."
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."
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."
Abstract This paper explores the chemical structure and clinical uses of technetium-based radio-pharmaceuticals which have since the 1970s, served as the mainstay for every hospital's nuclear medicine department. Today, fully 85% of all diagnostic scans in American hospitals use 99mTc in some chemical form. It includes a brief overview of several "technetium-essential" and "technetium-tagged" radio-pharmaceuticals, as well as a discussion of current areas of research and development for new technetium drugs.
From the Paper "Technetium-99m has several physical properties that make it ideal for use in nuclear medicine. Foremost among these is that Tc-99m generally emits only gamma rays. These gamma ray photons are of a high enough energy (140,000 eV) that they can easily pass through dense tissue and exit the body, but can be effectively stopped and detected by a special gamma camera. Other radionuclides generate alpha and/or beta particles, which are diagnostically useless since they lack the penetrating ability to exit the human body. Worse, the ionizing ability of these decay products can damage tissue."
