Word: billionths
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...sensitivity of the technique extends to one-billionth of a gram. It is a marvel at detecting the presence of poison, easily spotting a thimbleful dissolved in ten tank cars of water. Neutron analysis can get along with specimens far smaller than those needed for conventional chemical analysis: a fragment of lint, a strand of hair, a fleck of paint will suffice. Happily, the radioactivity caused by the neutrons soon dies down, and once studied, the evidence can safely be brought into a courtroom...
...Using a beam of high-energy electrons from Stanford's linear accelerator as a sort of microscope, he and a team of assistants proved that protons and neutrons, which form the bulk of matter, are dense at their centers, cloudlike outside and only one forty-thousandth of a billionth of an inch in diameter. Later research taught Hofstadter that protons, which have positive charges, and neutrons, which are electrically neutral, are similar in structure. The main difference is that the negative cores of neutrons balance out the positive charge on the outside...
...sometimes creates five mesons-two positive pions, two negative pions and one pion with no charge at all. For a fleeting instant, one positive and one negative pion cling to the uncharged pion, forming a single unit. That unit lives for only 10²² (one ten-thousand-billion-billionth) seconds. It travels only one ten-billionth of a centimeter before it disintegrates. But in the precise world of physics, this short life is enough to get a particle classed as actual matter. The Berkeley physicists decided that their invisible particle was the long-sought omega...
...last the chemists isolated a small drop (20 mg.) of colorless, oily stuff, odorless to humans but with an enormous attraction for male gypsy moths. It could be diluted almost endlessly. Less than one ten-thousandth of a billionth of a gram (10 -7 microgram) of it was enough to bring eager males fluttering out of the woods. When the potent oil was analyzed, it proved to be a surprisingly simple chemical (10-acetoxy-1-hydroxy-cis-7-hexadecene) that can be synthesized for $5 per Ib. Dr. Jacobson has about 1 Ib. on hand. If it were diluted...
...light exerts some pressure, but not much. Even the powerful sunlight glaring in empty space has the pressure of only one billionth of a pound per square inch-roughly equivalent to the weight of two cigarettes pressing on an acre of land. But in the vacuum of space, it was enough to push Vanguard I a mile or so off course over a period of two years. Light pressure is important in astronomy; it forms the tails of comets and is probably responsible for distributing the debris of exploded stars throughout the galaxy. But not until Vanguard I had been...