Word: ruben
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Dates: during 1940-1949
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...grotesque fragments last week lay a venerable theory which sought to explain the most important chemical reaction on earth: photosynthesis. Theory-busters were a group of young biochemists, headed by Samuel Ruben, at the University of California. They have penetrated deeper than anyone so far into the mysterious process by which the sun's energy pouring earthward in the form of light is captured by chlorophyll and stored as carbohydrates, the basic food of animal life...
Unimpressed with this explanation was Biochemist Cornelis Bernardus van Niel of Stanford. "Forget about sugar," he told his students. "Consider the other end-product-oxygen. Where does it come from? Discover that and you will be closer to the whole solution." Dr. Ruben at California took this line...
Hitch was that both the raw materials of photosynthesis, H 2 O and CO 2 , contain identical oxygen atoms. There was no way of telling them apart. So Ruben obtained heavy oxygen-a rare isotope which has a mass of 18 instead of the normal atomic weight of 16-and made from it heavy-oxygen water. This was fed to a green plant, together with ordinary, light-oxygen carbon dioxide. As photosynthesis proceeded, the scientists caught the freed oxygen, found it was the heavy variety. Next they fed the plant light-oxygen water and heavy-oxygen carbon dioxide...
...similar "tracer" experiment, Ruben & Co. introduced radioactive carbon into plants (TIME, June 23), were later unable to find any radioactive formaldehyde in them. (Formaldehyde is poisonous to plants, anyway.) This was another blow to the old theory...
...from the sun, which agitate atoms in the upper air to the glow point. For a long time the spectrum lines corresponding to the auroral colors were called "forbidden lines'' because they could not be reproduced in the laboratory. Last week Drs. Joseph Kaplan and S. M. Ruben of U. C. L. A. told how they brought the auroral colors down to earth. They put gas molecules in a tube, stirred them up with a high-frequency discharge, then snapped off the current with extreme suddenness. The brief afterglow of the gases they caught in a spectroscope. They...