Word: carbone
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Toward Synthetic Cells. Biochemist Sidney W. Fox of Florida State University reported progress toward creating life in the laboratory. Experimenters have long known that when a mixture of methane, ammonia, carbon dioxide and water vapor (all probable constituents of the earth's primitive atmosphere) is bombarded with electric sparks or high-energy radiation, amino acids are produced. Amino acids are the building blocks that form the multitudinous proteins in living organisms, and Dr. Fox carried the process a step farther. When he heated a mixture of amino acids with polyphosphoric acid as a catalyst, he got big molecules with...
Such deliberate mummification was practiced chiefly by the ancient Egyptians. But when Dr. Mori took the mummy back to Italy and had its age measured by the carbon 14 method, it proved to be 5,400 years old-considerably older than the oldest known civilization in the valley of the Nile 900 miles to the east...
Graphite, the substance in lead pencils, is a form of carbon that has long been one of the most useful minerals in the scientific laboratory and in industry. It is soft enough to be a good dry lubricant; its high heat resistance makes it a good material for crucibles and as a moderator in nuclear reactors. In the new age of rocketry, scientists have eyed it for use in rocket nozzles or in nose cones, which must resist the heat of reentry. But ordinary graphite has two faults: it is permeable to gases and is structurally so weak that...
Three years ago, Raytheon Co. of Waltham, Mass, set out to see what it could do to cure these shortcomings. Its scientists started with the knowledge that when carbon-rich gases are put in a lab furnace and decomposed by high heat, they sometimes deposit carbon in the form of a peculiarly dense graphite. At first this stuff was only a laboratory curiosity, and for a long time no one made it in quantity or thoroughly tested its properties. But after considerable experimentation, Raytheon's furnaces yielded a hard, impermeable, layered material that looks like black porcelain. Called Pyrographite...
This peculiar behavior is explained by the structure of graphite crystals, whose carbon atoms are arranged in sheets one atom thick. When the sheets are stacked up in a crystal, the distance between the atoms in adjoining layers is more than twice as great (3.35 angstroms*) as the distance between the atoms in the individual sheets (1.42 angstroms). In ordinary commercial graphite, microscopic crystals are jumbled almost at random, but in Pyrographite they are mostly aligned with their sheets parallel (see diagram). This builds up a layered structure that resists the motion of heat across the layers but permits easy...