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Only when the Curies appeared on the scene in 1898 and discovered the highly radioactive radium was life put into this area of research. So there was not much time left for the study of radioactivity. The scientists had thrown themselves into the investigation into X-radiation, for the world was fascinated by the perspectives which the application of this far more intense radiation opened up in the field of medicine. The professional circles at home and abroad were informed about Becquerel's discovery, but they were not much interested in it, the less so as the radiation was weak and a great number of experts did not quite believe it. For the moment, radioactivity was observed only in uranium-containing substances. With this, a new natural phenomenon had been discovered, which two years later was referred to by Marie Curie as "radioactivité". The crystal obviously emitted a penetrating radiation similar to the X-radiation which had been discovered shortly before.
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Even when thin glass plates or tin foils were placed between crystal and photoplate, this phenomenon did not disappear. As early as one week later he recognized that the crystal produced the same blackening effect even when it was in the dark and did not shine at all. On February 24, 1896, Henri Becquerel reported before the Académie des Sciences in Paris that a specific uranium-bearing crystal which had been brought to shine under the action of sunlight and had then been placed on a photographic plate wrapped in dark paper had blackened the photoplate.
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4 In 1899 Paul Villard expanded Rutherford’s findings with the announcement of a third ray, eventually called the gamma ray. Thomson, discovered that radiation was not composed of a single particle but instead contained at least two types of particle rays which he named alpha and beta. The following year, Ernest Rutherford, a researcher with ties to J. Through this process, she discovered two new elements which she named polonium and radium. In her search to uncover the cause she undertook the difficult task of isolating and identifying the components of pitchblende. In experimenting with pitchblende, a uranium-rich mineral, Curie found much higher concentrations of radiation than uranium was known to emit. Two months later, Marie Curie, a scientist in Paris, made the same discovery. He soon found that only thorium produced them. In 1898 Gerhard Schmidt of Germany began to investigate the question of whether or not other elements naturally emitted Becquerel rays. 2 After further refining his theory, he received the 1906 Nobel Prize in Physics. He suggested that these particles moved within the positively charged atomic body, explaining the atom’s neutral charge. Thomson found that atoms were not indivisible as previously thought, but instead contained even smaller particles which he called corpuscles. 1 He discovered that certain substances, such as uranyl sulfate, emitted rays with properties similar, though not identical, to those discovered by Röntgen. In 1896 French physicist Antoine Henri Becquerel began his own experiments on Röntgen’s X-rays. He called these mysterious emanations X-rays. To his surprise, he discovered that electricity in a vacuum produced rays that caused material to fluoresce and, under certain conditions, even illuminate the human skeleton. In 1895 German physicist Wilhelm Conrad Röntgen began a program of study on the behavior of electricity when subjected to certain variables.