Science Projects And Inventions

"The medics used the [super glue] spray, stopped the bleeding.... And many, many lives were saved." Harry Coover In 1942 Harry Coover (b. 1919), a chemist working for Eastman-Kodak, was seeking a way to manufacture ultra-clear plastic gunsights. The group of chemicals his team were investigating, the cyanoacrylates, proved not very useful. They were very sticky, and contact with even a tiny amount of water (such as is found on virtually every surface) caused them to bind. It was not until several years later, when he revisited the cyanoacrylates while working on another project, that Coover realized they had stumbled upon something special. The prototype glue stuck together everything they tried, without requiring any heat or pressure. The substance, marketed as "Eastman 910"in 1958, became popularly known as super glue. As well as being a powerful and useful adhesive, super glue has been put to a number of other uses. more...

Electroplating, sometimes called electrodeposition, is the process by which an electric current, provided by an external supply of direct current such as a battery, is passed through a solution resulting in the chemical breakdown of this electrolyte. This results in metal being transferred from one electrode—the anode— via metal ions in the solution, to the other—the cathode—which has the effect of the target object being coated with a thin layer of the metal that had formed the anode. The Italian chemist Luigi Brugnatelli (1761-1818) is credited with inventing electroplating in 1805. He used Alessandro Volta's earlier invention of a battery, the voltaic pile, to facilitate the first electrodeposition. Electroplating is used in many industries for decorative as well as functional purposes. It can increase the value or improve the appearance of an object. For example, jewelry is often gold-plated, and silverware may be made of cheaper metal coated with silver. more...

“Fill your bowl to the brim and it will spill. Keep sharpening your knife and it will blunt." Lao Tzu, Taoist philosopher When the Swiss Karl Elsener (1860-1918), owner of a company that made surgical equipment, found that the pocket knives supplied to the Swiss army were, in fact, made in Germany, Elsener decided to make them in Switzerland. With help from engineer Jeannine Keller, he launched a multifunctional pocket knife in 1891. Called the "Soldier's Knife," it had a wooden handle and incorporated a cutting blade, screwdriver, can opener, and punch. The knife was adopted by the Swiss army, but Elsener continued to work on the design. In 1896 he developed a knife with blades at either end of the wooden handle and a spring to hold them in place. This innovation enabled Elsener to increase the number of useful tools in the handle for the Swiss army, so more...

Russell Ohl (1898-1987) was a precocious talent who by the age of sixteen had already entered Pennsylvania State University After a period in the Army Signal Corps and a brief career as a teacher, OhI finally took a research position in U.S. industry. Early radios were only able to receive low- frequency transmissions. At Bell Labs in Holmdel, New Jersey, Ohl worked to create an improved radio receiver for high frequencies. Here he experimented with semiconductor materials that he thought would outperform the electron tubes used in existing receivers. An expert in the behavior of crystals, Ohl investigated different materials for semiconductors, such as germanium and silicon. The crystals were heated, and when cool would be sliced for use. In 1939 Ohl was working with a silicon sample that he noticed had a crack down the middle. When he tested the electrical resistance of the sample he noted that when more...

"An antibiotic for all seasons, it's used for a dozen reasons... there is no proxy, for our antibiotic doxy." James McCallum, from the poem "Doxycycline" The world existed for a long time without antibiotics, but as soon as they were discovered, the race was on to find more. Penicillin and streptomycin had both been isolated from some form of fungus, and the search continued for products that came from naturally occurring bacteria. Research groups looked everywhere but one of the more promising avenues of investigation began to emerge from groups studying certain fungi that lived in soil—organisms known as actinomycetes. Lederle Laboratories found the now forgotten antibiotic aureomycin in dirt samples. Pfizer soon followed suit with the equally obscure antibiotic terramycin. Both aureomycin and terramycin functioned as broad-spectrum antibiotics, covering a range of both gram- positive and gram-negative bacteria. This sparked a great deal of interest in figuring out how more...

"The Space Shuttle is the most effective device known to man for destroying dollar bills." Dana Rohrabacher, U.S. Congressman Booster rockets—such as the Saturn V that launched the Apollo astronauts toward the Moon—are extremely wasteful. They can fly only once, parts are thrown away after use, and 97 percent of the mass is Consumed in the first few minutes. Clearly, what was really needed for advanced and economic space exploitation was a spacecraft that could take off and return, to be reused time after time. In 1972 NASA-.in the United States decided to build the Space Shuttle. Rockets were to be used to assist the launch. Crew facilities were to be provided for up to eight people, and the huge cargo bay would be used to take satellites and sections of the International Space Station (ISS) into orbit. New instruments would also be taken up to existing spacecraft, and In-orbit more...

In 1952 Gregory Pincus (1903-1967), a biologist working at the Worcester Foundation for Experimental Biology in the United States, demonstrated that a synthetic form of the hormone progesterone, known as norethidrone, inhibited ovulation in rabbits and rats. Norethidrone had been developed a year earlier by Carl DJerassi, a chemist working at the Syntex company in Mexico City. It had initially been created with the aim of producing high concentrations of progesterone to treat menstrual disorders. It had the advantage of being more active than the human hormone, and also of being effective when taken orally. Margaret Sanger, founder of the American Birth Control League, saw the potential of Pincus's work. She enlisted the help of heiress Katharine McCormick, who agreed to fund research to develop a contraceptive pill. Pincus developed a pill with the aid of gynecologist John Rock (1890-1984), a devout Catholic aiming to improve conception among infertile couples. more...

"If... you had to shift into low gear, the motor scooter would jump about ten yards ahead..." Thomas Fogarty The centrifugal clutch owes its existence to the frustration Thomas Fogarty(b. 1934) experienced With the gears of his motor scooter. A traditional car clutch works via longitudinal mechanical motion, disconnecting the driveshaft for the wheels from the motor by moving a pressure plate away from the clutch disc. The centrifugal clutch works differently, using the rotational motion of the motor to engage and disengage the driveshaft The clutch is cylindrical, with the crankshaft from the engine rotating in its center. Attached to this shaft is a pair of weights that are held in place by springs. The crankshaft and weights rotate together, at the same number of revolutions per minute (rpm) as the engine. When the engine increases in rpm, the revolution speed of the weights also increases and they swing more...

Chinese government official Su Song (1020-1101) was also a naturalist, cartographer, astronomer, horologist, and engineer. His greatest legacy was the clock tower he built in Kaifeng. In 1086 the emperor had ordered the construction of an "armillary clock" to keep time and track celestial bodies. A finished structure was completed in 1094, and consisted of three levels. The upper level contained a rotating armillary sphere that allowed astrological observations through sighting tubes; the middle level had a bronze celestial globe; and the lower level had mechanically timed manikins that would exit doors at fixed times of the day. Perhaps most significant, however, was the clock's innovatory driving system. At the heart of the clock tower was the tian ti, or "celestial ladder." This is the oldest known endless power-transmitting chain drive. The chain transmitted the power from a water wheel to turn the armillary sphere and power the clock. Drive more...

Given its market domination from the moment it first appeared in 1979, many people might imagine that the Sony Walkman was the original personal cassette player. Its iconic status is beyond question—it all but created the vogue for listening to music on the move and is a direct antecedent of today's ubiquitous iPod. And yet seven years earlier, a lone inventor with little expertise in the field of electronics came up with a concept that was almost identical. The story begins in Brazil in 1972 when a German- born former TV executive named Andreas Pavel(b. 1945) sought a way of listening to high-quality music while going about his everyday business. His idea was for a tiny portable cassette player—not that much larger than the cassette itself—that played back audio through a small pair of headphones. He called his novel idea the Stereobelt. Having left Brazil and moved to Switzerland, Pavel more...