Word: x-rayed
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
...implications of Stroke's work are important. Scientists must know the three-dimensional structure of biological molecules if they are to understand fully how they are assembled and how they function. A primary means of obtaining this knowledge is X-ray diffraction, a process in which molecules are first crystallized, then examined by X rays. The data collected can be analyzed by computer and then used to draw elaborate "electron density" maps from which complex models can be built...
...team first crystallizes the molecule to be studied. The crystal is then examined by standard X-ray diffraction; the X rays that pass through the crystal and bounce off the atoms are used to make a pattern of dots that is recorded by an electronic counter. The diffraction pattern is then processed by computers to determine the relative value of each of its spots. Finally, the spots are printed on a photographic plate, which becomes a hologram of one of the crystal's planes...
...aide to National Football League Commissioner Pete Rozelle. Granholm begins by cornering 15,000 hotel rooms. Before the game is over, he and the rest of the league staff will have seen to everything from towels and hot dogs to brackets for televisions in the press box to X-ray machines for diagnosing injuries, to coat hangers for clotheshorse athletes to an elaborate security system designed to ensure that nothing can possibly go wrong on Super Sunday...
...using such instruments as the huge 200-in. optical telescope on Mount Palomar and newer radio, X-ray and gamma-ray telescopes, modern-day stargazers have pushed the frontiers of understanding even closer to the edges of the universe and into the very cores of the stars. With increasing confidence, astrophysicists are answering some of the questions that man has asked from the time he became a rational being: How far away are the stars? What makes them shine? How long have they been there, and will they exist forever...
Because black holes emit no light or other radiation, their existence, predicted by the laws of relativity, cannot be confirmed by direct observation, but it can be inferred. Astronomers have identified a powerful X-ray source in the constellation Cygnus. Some suspect the source, which has been labeled Cygnus Xl, may be just such a black hole. It appears to be rotating with a visible star around a common center of gravity−a dead partner of a dualstar system. Scientists believe material from the glowing star is being drawn into the black hole with such force that the material...