Essays on Science

... 6- 7). Portland cement is produced by pulverizing clinker consisting essentially of hydraulic calcium silicates along with some calcium aluminates and calcium aluminoferrites and usually containing one or more forms of calcium sulfate (gypsum) as an interground addition. Materials used in the manufacture of portland cement must contain appropriate proportions of calcium oxide, silica, alumina, and iron oxide components. During manufacture, analyses of all materials are made frequently to ensure a uniformly high quality cement. Selected raw materials are crushed, milled, and proportioned in such a way that the resulting mixture has the desired che ...

... uses. Lysergic acid deviates were found to relieve migraines and control postpartum hemorrhage because it causes veins to contract, but also caused gangrene of the limbs, and so further experimentation with the drug was abandoned. In the late 50's, however, LSD was used by the CIA as an interrogation drug for spies. However, it was proven to be unreliable and was later replaced with other interrogation drugs. LSD comes in the forms of crystals, liquids, tablets, gelatins, or blotting squares. The squares have designs on them such a flowers, dragons, shapes, animals, and cartoon characters to make them more attractive to young children. Often called acid, ...

... own opinion on the matter. One might go so far to say as science and the Bible are God’s most basic forms of communication with the human; thus scientific deduction of the Bible should allow us to solve the mystery of man’s and the universe’s origins. A very highly debated topic within the bigger argument is, “What started it all?” Creationists believe that God merely spoke all that we know into existence, but evolutionists prefer to believe a massive, random explosion spawned the cosmos. Obviously, a middle-grounder could find both preposterous. The very first line of the Holy Bible states, “In the beginning, God created the heavens and the earth.” ...

... would not cause a fire, but just below the cuts in the cable was a length of aluminum tubing, which took a ninety-degree turn. There were hundreds of these turns in the whole capsule. The aluminum tubing carried a glycol cooling fluid, which is not flammable, but when exposed to air it turns to flammable fumes. The capsule was filled with pure oxygen in an effort to allow the astronauts to work more efficiently. It also turns normally not so flammable items to highly flammable items. Raschel netting that was highly flammable in the pure oxygen environment was near the exposed section of the wires. At 6:31:04 p.m. the Raschel netting burst into an open f ...

... Six kinds of shock waves are generated in the process. Two are classified as body waves-that is, they travel through the earth's interior-and the other four are surface waves. The waves are further differentiated by the kinds of motions they impart to rock particles. Primary or compressional waves (P waves) send particles oscillating back and forth in the same direction as the waves are traveling, whereas secondary or transverse shear waves (S waves) impart vibrations perpendicular to their direction of travel. P waves always travel at higher velocities than S waves, so whenever an earthquake occurs, P waves are the first to arrive and to be recorded at geoph ...

... area degenerates it leads to scarring or hardening ("Sclerosis") in the region. Over 5,000 Americans are diagnosed with ALS each year. There is great variation in the course of the disease. Symptoms usually appear in individuals between the ages of 40-70, though the disease has been reported in both younger and older persons. Survival after the confirming diagnosis is, on average, two to five years. Progression of ALS varies with each individual; therefore, some will live longer--up to 10 years, and about five percent will exceed 12 years. In some cases, the disease seems to plateau. Many patients are able to live productive and satisfying lives especially with ...

... and books on the topic of eating disorders that could affirm my feelings. As I tried to rationalize my friend's behavior, I decided that social acceptability had to have played a large part in her illness. I also took into account that her mother had passed away about 7 years before she broke her news to me, and she had also given up her crown as Miss Iowa, so depression could have been a factor as well. Another aspect of eating disorders that I discovered is a lack of self-esteem, something I never imagined. The first source I found to dispute the sexual repression hypothesis was in Psychology Today. Dr. Sarah Leibowitz theorized t ...

... over night. It happens over a period of many years, or even decades. The changes are usually to gradual for them to be noticed early. At the beginning of the 20th century most rivers and lakes like the river Tovdal in Norway had not yet begun to die. However by 1976 local inspectors were noticing that many of the lakes were beginning to show signs of death. Fish were found dead along the banks of many rivers. As the winters ice began to melt off more and more hundreds upon hundreds more dead fish were being found. As scientists continued to work they found many piles of dead fish, up to 5000 in one pile, further up the river. Divers were sent in to examine ...

... resistant to decay. Community water fluoridation is the adjustment of the amount of the beneficial trace element fluoride found in water to provide for the proper protection of teeth. Fluoridation has been widely utilized in this country since 1945. It does not involve adding anything to the water that is not already there, since virtually all sources of drinking water in the United States contain some fluoride. Fluoridation is a form of nutritional supplementation that is not unlike the addition of vitamins to milk, breads and fruit drinks; iodine to table salt; and both vitamins and minerals to breakfast cereals, grains and pastas. The protection of fluoridation ...

... These solutions involved making environmental changes on the international, industrial, and personal levels. Just how does acid rain form, and what consequences does it pose to our environment? There are numerous theories as to the cause of acid rain. However, the most prevalent is the theory that electric generating plants, heating plants, and other industrial plants have been emitting an excess amount of sulfur oxides, nitrogen oxides, and volatile organic chemicals (VOC’s) into the atmosphere. Once these chemicals are in the air, they react with water to form acids and fall back to the earth as precipitation. People who believe acid rain is a natural ...