Beryllium radiation

The beryllium radiation when passed through any substance containing hydrogen knocks out high velocity protons. 

High Beryllium Radiation Pusher (e.e. Depleted L , explosives reflector shield U.PborW)... 

Irdne Joliot-Curie reported her first results to the French Academy of Sciences on December 28, 1931. The beryllium radiation, she found, was even more penetrating than Bothe and Becker had reported. She standardized her measurements and put the energy of the radiation at three times the energy of the bombarding alpha particle. 

The Joliot-Curies decided next to see if the beryllium radiation would knock protons out of matter as alpha particles did. They fitted their ionization chamber with a thin window, explains Feather, and placed various materials close to the window in the path of the radiation. They found nothing, except with materials such as paraffin wax and cellophane which already contained hydrogen in chemical combination. When thin layers of these substances were close to the window, the current in the ionization chamber was greater than usual. By a series of experimental tests, both simple and elegant, they produced convincing evidence that this excess ionization was due to protons ejected from the hydrogenous material. The Joliot-Curies understood then that what they were seeing were elastic collisions—like the collisions of billiard balls or marbles—between the beryllium radiation and the nuclei of H atoms. 

New metliods appear regularly. The principal challenges to the ingenuity of the spectroscopist are availability of appropriate radiation sources, absorption or distortion of the radiation by the windows and other components of the high-pressure cells, and small samples. Lasers and synchrotron radiation sources are especially valuable, and use of beryllium gaskets for diamond-anvil cells will open new applications. Impulse-stimulated Brillouin [75], coherent anti-Stokes Raman [76, 77], picosecond kinetics of shocked materials [78], visible circular and x-ray magnetic circular dicliroism [79, 80] and x-ray emission [72] are but a few recent spectroscopic developments in static and dynamic high-pressure research. 

Neutron radiation is emitted in fission and generally not spontaneously, although a few heavy radionueleides, e.g. plutonium, undergo spontaneous fission. More often it results from bombarding beryllium atoms with an a-emitter. Neutron radiation deeays into protons and eleetrons with a half-life of about 12 min and is extremely penetrating. 

Benztriazole, derivatives 281 ff 2-(2-Hydroxy-5-niethylphenyl)- 282 2-(2-Hydroxy-3-(l -methylpropyl)-5-tert-butylphenyl- 283 Berberine reagent 44,213 Beryllium cations 144,145,311,312 Besthorn s hydrazone reagent 347 Beta-blockers 74, 299, 301, 426—428 Beta-fronts 126 Beta-radiation 12 Betulae, Extr. 279 Betulic acid 59... 

Beryllium is an excellent source of alpha particles, which are the nuclei of helium atoms. Alpha particles (radiation) are not very penetrating. These particles travel only a few inches in air and can be stopped by a sheet of cardboard. Alpha particles are produced in cyclotrons (atom smashers) and are used to bombard the nuclei of other elements to study their characteristics. 

Rutherford and Chadwick knew that if the Joliots realized that their conclusions were erroneous, they might discover the neutron first. So Chadwick immediately went to work performing new experiments. He soon found that if beryllium was bombarded with alpha particles, a kind of radiation consisting of particles with a mass close to that of the proton were produced. He ruled out the possibility that the radiation consisted of gamma rays by showing that, if it did, the gamma rays would have insufficient energy to produce the effects that were observed. Chadwick had discovered Rutherford s neutron. 

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