Martens-Latem, Belgium, Leo Hendrick Baekeland was the son of a cobbler Karel Baekeland and a housemaid Rosalia Merchie. in 1884, together with the highest honors, in organic chemistry from the University of Ghent. He joined the faculty at Ghent, which was then a leading center for the learn of coal tar compounds. Interested in becoming an inventor, Baekeland atom structure scholarship to see the United States in 1889 the year he married Celine Swart. His interest in photographic development brought him into contact with Richard Anthony of E.
Anthony and Company, who recruited Baekeland to join his American-based photographic company. After 3 years Baekeland became an independent consultant, but he had little money and little prospects. Nevertheless, subsequent to experimenting with silver chloride emulsions, he developed a high-quality photographic printing paper, called Velox, sensitive enough to be used with artificial light. In 1899 the Eastman Kodak Business located in Rochester, New York bought the rights to Velox from Baekeland and his partner Leonard Jacobi for $750,000. This product represented a good leap forward in technological photographic technology.
At his home lab in Yonkers, New York, Baekeland then returned to his early interest in resin chemistry. Reacting phenol and phenol derivatives with formaldehyde, he learned enough about controlling the aldehyde -phenol ratio with acids and alkalis to synthesize multiple resins. Most notable was the phenol-formaldehyde polymer resin Figure two he produced with an alkali catalyst. Baekeland developed high compression and high heat techniques that greatly improved the molding of this plastic, which he named Bakelite and patented in 1909. It was a super hard, lightweight, insoluble glass with a tensile strength of 7,000 pound force per square inch psi.
Baekeland claimed to have synthesized first true plastic. In 1910 Baekeland founded the General Bakelite Corporation in Perth Amboy, New Jersey, which began producing Bakelite on a commercial scale the following year. Bakelite was sold in liquid and powder shape for molding to specifications. It quickly gained popularity in an alternate categories of household and non-residential usessuch as electrical insulation, billiard balls, tabletops, switchboards, and later automobile ignition systemswhere it often replaced natural fabrics or earlier plastics, mostly celluloid. By 1939 the factory was producing higher than 50 million pounds of Bakelite a year.
Baekeland and his firm controlled higher than 400 patents. However, competition from primary chemical businesses was intensifying, and Baekeland's son George, who had worked for the business since 1923, did not wish to sprint it. So Baekeland, then seventy-five, sold the firm to Union Carbide and Carbon Corporation for roughly $16. Baekeland earned many honors and awards, within the Franklin Medal regarding the Franklin Institute 1940, and the Perkin Medal 1916 and Messel Medal 1938 regarding the Society regarding the Chemical Industry. He was also elected president regarding the Chemists Club of New York 1904? the American Electrochemical Society 1909? the American Institute of Chemical Engineers 1912? and the American Chemical Society 1924.
Eccentric in his old age, Baekeland spent many of his time alone, often in Coconut Grove, Florida, consequently he maintained a well correspondence with a many colleagues on a broad section of subjects. He died in Beacon, New York, on February 23, 1944. Becquerel, Antoine-Henri. Antoine-Henri Becquerel was born as the son regarding the physicist Alexandre-Edmond Becquerel, and the grandson regarding the physicist Antoine-Csar Becquerel, and it is not surprising that he followed in their footsteps. It shall also be not surprising that his studies interests centered on solar radiation and phosphorescence, as these are phenomena that his father had investigated.
He entered the cole Polytechnique, in Paris, in 1872, which he left in 1874 and to which he subsequently returned. Becquerel received a doctorate degree from the Faculty of Sciences of Paris in 1888. In 1892, he was appointed professor of applied physics within the Department of Natural The past at the Paris Museum, and in 1895, professor of physics at the cole Polytechnique. Becquerel's early work focused on plane-polarized light, the phenomenon of phosphorescence in which sure compounds glow subsequent to being exposed to direct light, and the absorption of light by crystals. But all of his early studies became overshadowed by his discovery of natural radioactivity.
Consequently Becquerel did not initially comprehend what he was observing, his landmark discovery of radioactivity paved the method for an unique understanding regarding the atom and atomic structure. On February 24, 1896, Becquerel attended a meeting regarding the French Academy of Science and presented a brief cardboard one regarding the quickest methods in Rome at that time for disseminating results. One can well imagine Becquerel's excitement as he reported his conclusions to members regarding the academy. One wraps a Lumiere photographic plate with a bromide emulsion in 3 sheets of very thick black paper, such that the plate does not grow to clouded upon being exposed to Sun for a day. One locations on the sheet of paper, on the outside, a slab regarding the phosphorescent substance, and one exposes the whole to Sun for multiple hours.
When one then develops the photographic plate, one recognizes that the silhouette regarding the phosphorescent substance appears in black on the negative. From this simple experiment, Becquerel concluded that the phosphorescent substance had to be emitting a kind of ray that was passing through the cardboard and reducing the silver within the emulsion. This should seem to make sense, as the production of X rays, discovered a little years earlier by Wilhelm Rntgen, is accompanied by a soft glowing spot at the surface regarding the cathode ray tube. Becquerel decided to probe his unusual rays little further. One week later, on March 2, 1896, Becquerel was return prior to the French Academy together with the conclusions of his distant experiments.
He had continued his experiments creating use of a double sulfate pepper of uranium and potassium potassium uranium sulfate monohydrate, which has a tough but short-lived phosphorescence. He carefully wrapped his photographic plates in black paper, coating the cardboard with a crust regarding the uranium double salt, and upon exposure to sunlight he once repeatedly observed the signature regarding the phosphorescence induced rays. However, repeating the experiment on Wednesday, February 26, and Thursday, February 27, he was frustrated by 3 days of only intermittent sunlight. And due to the fact that the Sun created no appearance on the 3 days following, on March two he developed his plates. Expecting to look only a faint silhouette resulting from the wrapped plates' intermittent exposure to sunlight, he was surprised to look that the silhouettes appeared with good intensity.
Becquerel suspected that the rays which produced the silhouettes emanated from the uranium pepper itself, and that the tiny no. of sunlight was of no consequence. He arranged 3 more experiments, in which photographic plates were kept completely within the dark but place in direct contact with: two the salt; 3 a thin sheet of glass; and 4 a thin sheet of aluminum. He surmised that the glass should eliminate any possibility that a silhouette was the consequence of a chemical reaction, and that the aluminum should block the mysterious rays. Developing the photographic plates, Becquerel observed an intensely defined silhouette on first 3 plates, and a simple but considerably weaker silhouette on the third.
Due to the fact that he had double-boxed his plates inside his dark room and had placed the ensembles inside a drawer that he then closed, he was can conclude that his mysterious rays were not related to phosphorescence and were not induced by sunlight. It was another 4 years prior to Becquerel's radiation became understood as the production of -rays high life electrons, but by then there was no question that Becquerel had discovered the instability of some atomic nuclei, and that he was richly deserving regarding the 1903 Nobel Prize that he shared with Pierre and Marie Curie.
No comments:
Post a Comment