Word: sunlight
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Dates: during 1970-1979
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...blaze of morning sunlight the buildings are white, elegant and French in downtown Algiers. Although the streets are named after Algerian martyrs, their design is French colonial. White stucco, palm trees and street cafes appear in regular sequence and converge at a large square or park. Their sharp angularity seems out of place in this hilly city decorated with Islamic arabesques...
Despite their progress in developing solar cells, giant reflectors and other devices, scientists still lag far behind nature in their ability to harness solar energy. No man-made device can match the performance of the green pigment chlorophyll: through the process of photosynthesis, it converts some 30% of the sunlight striking it into the chemical energy that plants use to create their own food. Even more frustrating, chlorophyll has defied the efforts of scientists to use it directly to produce energy for man; the pigment is highly unstable...
...employ a natural converter to get energy directly from sunlight. Last week Cell Biologist Walther Stoeckenius, 54, with colleagues at the University of California at San Francisco and a team from NASA'S Ames Research Center, announced that a purple pigment found in red bacteria from the Dead Sea and salt flats round the world also directly converts sunlight into energy. While the pigment is less efficient than chlorophyll-only an estimated 10% of light energy is converted-it is more stable and easily extracted from the bacteria...
Continuing his research after transferring to California in 1967, Stoeckenius found that the pigment, called bacteriorhodopsin, functioned as a sort of pump, converting sunlight directly into electrochemical energy. Light striking a pigment molecule causes it to eject a hydrogen ion-or proton-that passes through the cell's membrane. The movement of the positively charged protons through the membrane leaves an excess of negative charge on one side of the membrane. That produces a voltage gradient and results in an electrical current flowing through the membrane. In the process, which involves at least five separate steps, each bacteriorhodopsin molecule...
...display of stagecraft, the Russians opened the Kremlin gates this week for the 25th performance of the classic miracle play of Communism: the Congress of the Communist Party of the Soviet Union. The onion domes and crosses atop the Kremlin's cathedrals and churches coruscated in the winter sunlight, while the renovated brick battlements of the ancient fortress loomed over the elegant imperial palaces, freshly painted in pastels. Outside the walls of the ancient fortress, huge posters dominated Red Square, proclaiming the principal theme of this year's political extravaganza: SUCh as GLORY TO THE GREAT SOVIET PEOPLE...