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Terms and Definitions
Published in Rick Houghton, William Bennett, Emergency Characterization of Unknown Materials, 2020
Rick Houghton, William Bennett
Alpha particles consist of two protons and two neutrons and are about 7,000 times more massive than a beta particle. The increased mass means alpha particle radiation can be stopped by a sheet of paper or the dead layer of skin cells on a human. Comparatively, alpha particle radiation is not much of a hazard to the skin, but there are serious inhalation, ingestion, and injection hazards. Epithelial cells that line the respiratory and gastrointestinal tract have no dead layer of cells for protection. A radioisotope dust that is swallowed or inhaled will settle directly on live cells and cause local irradiation injury. The same type of injury can occur with eye contact. Because alpha particles are large and prone to collision while delivering energy over a short distance, they have potential to cause severe biological damage. Alpha radiation can only travel a few centimeters through air. Alpha particles are emitted from substances such as plutonium, radon, and radium.
Radiation Hazards
Published in Dag K. Brune, Christer Edling, Occupational Hazards in the Health Professions, 2020
Particle radiation, such as electrons or beta rays from radioactive decay, is also ionizing radiation, as well as alpha, proton, and neutron radiation and many other kinds of subatomic particles in cosmic radiation. Radiation in which the quanta do not have enough energy to ionize atoms or molecules is called nonionizing radiation. UV light, visual light, IR light, microwaves, and radio frequency (Rf) radiation are electromagnetic radiation belonging to this category of radiation. Acoustic radiation (i.e., ultrasound and infrasound), which propagates through vibrations of the molecules in a medium, also belong to this category.
Characterisation of hydrogen ion implantation damage in quartz, lithium niobate and tellurium dioxide by Raman spectroscopy
Published in Radiation Effects and Defects in Solids, 2021
Barrett J. Taylor, Michael P. Bradley
The study of charged particle bombardment of transparent materials began in the early days of nuclear research with observations of radiation-induced darkening (3). The list of known optical effects has since grown to include effects such as the formation of colour centres and changes to refractive indices (2). Charged particle radiation causes damage by disrupting the atomic structure of the material by creating displacements, vacancies, and interstitial ions. Any material property that depends on specific bond structures is susceptible to change via radiation-induced damage. One such property is birefringence; a property extremely dependent on crystal structure. Due to the sensitivity of both the chemical bonding environment and the crystal structure (or lack thereof), Raman spectroscopy can be used to study charged particle radiation damage. For crystalline materials specifically, results can include the reduction in amplitude of Raman lines associated with the crystal structure, due to a reduction in the long-range crystal order, as well as the appearance of new Raman features associated with disorder and/or new bonds.
Why Human Enhancement is Necessary for Successful Human Deep-space Missions
Published in The New Bioethics, 2019
Konrad Szocik, Martin Braddock
Space radiation contains all elements of the periodic table which can enter the human body with almost speed of light and damage DNA and cells (Maalouf et al. 2011). Basic medical hazards caused by space radiation include cancer, mostly lung cancers (Kennedy et al. 2018), damage of central nervous system, degeneration of tissues and acute radiation risk causing skin injury or even death (NASA 2018b). Particle radiation may not only increase the risk of cancer after the mission, but it may also cause acute radiation sickness during the mission (Frazier 2015).