Radiation charged particulate

The interactions with a medium of charged particulate radiations such as protons, (p-particles, and y-rays consist predominately of electrostatic coulomb excitation and ionization caused by ejection of atomic and molecular electrons in the medium. According to Bethe s semiclassic treatment, the energy lost to the medium, per unit length of path, by a heavy particle of charge Ze and velocity v is ... 

The range of a charged particulate radiation in matter increases ... 

Energetic x rays and gamma rays penetrate tissue well enough so that an external source of such radiations may deliver a relatively uniform dose to all parts of the body. Particulate radiations, on the other hand, penetrate much less readily, especially those with high mass and charge, such as alpha particles. With such radiations, irradiation of deep-seated tissues wUl occur only as a result of internal deposition. 

Of the various ionizing particulate radiations, the most important in terms of likelihood for human exposure are alpha particles, beta particles, protons, and neutrons. Alpha and beta particles occur as a result of the radioactive decay of unstable atoms. Neutrons generally result from nuclear reactions, such as nuclear fission (as in nuclear reactors and fission-based nuclear weapons) and charged-particle activation of target atoms (as with some accelerator-produced... 

Beta particles are negatively charged and smaller, travel faster, and penetrate farther than alpha particles. A beta particle is 1/1800 the size of a proton, or roughly equal to an electron in mass (see Figure 9.5). Beta particles will penetrate the skin and travel from 3 to 100 ft. Full turnouts and SCBAs will not provide full protection from beta particles. Particulate radiation results in contamination of personnel and equipment where the particles come to rest. Electromagnetic energy waves, like gamma, do not cause contamination. 

Direct particulate radiation from soot particles within the flame to surfaces of the charged loads and walls that they can see ... 

The terms detector, transducer, and sensor are often used synonymously, but in fact the terms have somewhat different meanings. The most general of the three terms, detector, refers to a mechanical, electrical, or chemical device that identifies, records, or indicates a change in one of the variables in its environment, such as pressure, temperature, electrical charge, electromagnetic radiation, nuclear radiation, particulates, or molecules. This term has become a catchall to the e.x-tent that entire instruments are often referred to as detectors. In the conte.vt of instrumental analysis, we shall use the term detector in the general sense in which we have just defined it. and we shall use detection system to refer to entire assemblies that indicate or record physical or chemicalquantities. An example is the UV(ultra-... 

Besides being oppositely charged, the positron shows an even more fundamental difference from the electron It is the antiparticle of the electron. When a positron collides with an electron, the particulate matter is changed to electromagnetic radiation in the form of high-energy photons ... 

The transfer from the radiation induced charge within a particulate to its surface,... 

The particulate concentration In stack fuel gases must be determined to comply with current legislation on environmental pollution, which places emphasis on the particle size. By "particulate matter" is understood any solid or liquid material emitted to the atmosphere, Including dust, fumes, ash, soot, tar and droplets. These "analytes" can be monitored continuously by means of detectors based on the absorption of light or B-radiation or on the transfer of charge between particles. 

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