POLYPROPYLENE
November 12, 1999 - Bartlesville, Oklahoma, U.S.A.
In Bartlesville, Oklahoma, a plaque was placed on the site of the laboratory where the polymer polypropylene was invented, designating it a National Historic Chemical Landmark by the American Chemical Society. The first commercially successful use of the new material was in the Hula Hoop®. In 1951, J. Paul Hogan and Robert L. Banks, research chemists working for Phillips Petroleum Company, discovered the polymer unexpectedly during experiments with catalysts while trying to convert the natural gas components ethylene and propylene into compounds useful for gasoline. Later, they also developed a new catalytic process for making high-density polyethylene. Phillips soon invested in new plastic manufacturing plants.
PITOT TUBE
November 12, 1732 - Academy of Sciences, Paris
Henri Pitot read a paper to the Royal Academy of Sciences in Paris about an instrument he had invented to measure the flow velocity at different depths of water in the River Seine. It had a scale and two open vertical glass tubes on a wood frame. The lower end of one pointed down, the other bent at 90 facing the flow. The belief of the time was that flow velocity at a given depth was proportional to the mass above it, meaning increasing velocity at greater depth. Recording the difference in liquid levels in the two tubes, he showed the opposite was true. Henri Darcy improved the design, with the support of Henri Bazin. Today, the Pitot tube has an important application in aerodynamics for the measurement of the airspeed of aircraft.
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RANDOM QUOTES
The wealth of the nation
by Earth Day, Gaylord Nelson
"...The wealth of the nation is its air, water, soil, forests, minerals, rivers, lakes, oceans, scenic beauty, wildlife habitats and biodiversity that'as all there is. That'as the whole economy. That'as where all the economic activity and jobs come from. These biological systems are the sustaining wealth of the world...."
The Revolution
by John Adams
"...The Revolution was effected before the War commenced. The Revolution was in the minds and hearts of the people; a change in their religious sentiments of their duties and obligations. This radical change in the principles, opinions, sentiments, and affections of the people, was the real American Revolution...."
RANDOM FACTS
More vehicles
about Stolen On New Year's
More vehicles are stolen on New Year's Day than any other holiday throughout the year. (So does that mean thieves are having their last fling before changing their ways or are they trying for a big score to start the New Year?)
Cancer Facts & Figures
about Besides Lung Cancer
Besides lung cancer, tobacco use also increases the risk for cancers of the mouth, lips, nasal cavity (nose) and sinuses, larynx (voice box), pharynx (throat), esophagus (swallowing tube), stomach, pancreas, kidney, bladder, uterus, cervix, colon/rectum, ovary (mucinous), and acute myeloid leukemia.
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This is our Models category. If you are interested in Models, feel free to browse these listings. If you have a site that fits within this category, Submit it for inclusion.
Modellifestyle is the informative site about how to become a model. Here you can also find information about male modeling advice, female modeling advice, skin care tips, modeling catwalks, fashion...
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Each quarter, twenty general or topical web directories are evaluated and rated according to predetermined criteria. The top ten are placed in competition with one another and ten additional direct...
The course of the River Thames as we know it today was created about 10,000 years ago, by melt water from the ice-sheets that covered much of the United Kingdom during the last ice-age...
Search engine is the term with which we are accustomed with very much. But the web directory is not that same. The web directories are older than search engines according to the time of their invention.
Unfortunately just like humans our pets will age too. With the aging process comes health problems and with health problems comes very expensive vet bills. Research you dog