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Protecting Humans from the Harmful Effects of Radiation
Published in Robert E. Masterson, Nuclear Engineering Fundamentals, 2017
The becquerel (Bq) and the curie (Cu) are both ways to measure the “activity” or the number of particles emitted by a radioisotope. Thus the activity is a rough measure of the number of particles that a radioisotope emits per second. Of course, the activity can be correlated directly to the disintegration rate as well. Nuclear particles deposit their kinetic energy in materials as they move and this energy deposition is measured in what are known as RADs. The RAD is an acronym for “radiation absorbed dose.” The U.S. NRC uses the RAD to calculate how much energy particles of radiation deposit in various materials.Hence, the total dose D in conventional units is measured in RADs. Not all types of radiation (alpha rays, beta rays, neutrons and photons) cause the same amount of physical damage to living cells and because of this, another unit of radiation exposure called the REM was developed. The REM was first developed in an attempt to incorporate the effects of biology into the science of radiation exposure. Hence, the REM is used to measure of how much damage a given amount of radiation inflicts on the human body. This amount of biological damage is called the equivalent dose or the dose equivalent DE for short. The REM is an acronym for the roentgen equivalent man.
Radioactivity and radiation
Published in Alan Martin, Sam Harbison, Karen Beach, Peter Cole, An Introduction to Radiation Protection, 2018
Alan Martin, Sam Harbison, Karen Beach, Peter Cole
For many years, the unit of radioactivity was the curie (Ci), but this has now been generally replaced by the SI (Système International d'Unités) unit, the becquerel (Bq). The curie was originally related to the activity of 1 g of radium, but the definition was later standardized as 3.7 × 1010 nuclear disintegrations per second (dps), which is almost the same: 1 Ci = 3.7 × 1010 dps or 2.22 × 1012 disintegrations per minute (dpm)
Radioisotope Production and Application
Published in Paul R. Bolton, Katia Parodi, Jörg Schreiber, Applications of Laser-Driven Particle Acceleration, 2018
The curie (Ci) is the historical unit for radioactivity. It was introduced originally as the number of dps of one gram of 226Ra. This unit of activity was later set officially to the value of 3.7 × 1010 dps. Now the becquerel (Bq) is the SI unit of radioactivity and is defined as the activity that produces 1 dps, or 1 Bq = 1 dps. Therefore 1 Bq = 2.7 × 10–11 Ci, or inversely 1 Ci = 37 GBq. Typical doses are often measured in mCi (therefore, in terms of radioactivity level).
Interaction of L-ascorbic acid and α-tocopherol in alleviating 1, 4-benzoquinone, a metabolite of benzene induced genotoxicity in male Wistar rats
Published in Egyptian Journal of Basic and Applied Sciences, 2023
Ritu Mishra, Karabi Dutta, Manuj Kr. Bharali
The chromosomal aberration analysis of bone marrow cells of animals treated with BQ revealed significant (p < 0.05) increase in the number and percentage of aberrant cells when compared to the control group (Table 2). Chromatid and chromosomal gaps, breaks and deletion were found to be the prominent type of chromosomal aberrations in the present study (Figure 1b–f). The highest percentage of chromosomal aberrations (94.50%) was recorded after 24 h which decreased considerably after 48 h (92.13%) and 72 h (91.48%) of BQ treatment (Table 2). However, coadministration of L-ascorbic acid and/or α-tocopherol with BQ significantly reduced the frequency of abnormal metaphases as compared to only BQ treated animals (Table 2). L-ascorbic acid cotreatment inhibited BQ induced clastogenecity by 60.26%, 39.63% and 40.05% at 24 h, 48 h or 72 h post treatments whereas α-tocopherol was found to inhibit BQ-induced chromosomal damage by 77.42%, 69.94% and 72.56% at 24 h, 48 h and 72 h post treatments respectively (Table 2). Co-administration of L-ascorbic acid and α-tocopherol were able to inhibit BQ induced frequency of clastogenecity by 90.02%, 88.40% and 94.46% following 24 h, 48 h and 72 hr post treatments respectively (Table 2).
Photon Activation Analysis in Gallium, Nickel, and Vanadium
Published in Nuclear Science and Engineering, 2023
Robert Bentley, Geno Santistevan, Douglas Wells, Andrew Hutton, Adam Stavola, Steve Benson, Kevin Jordan, Joe Gubeli, Pavel Degtiarenko, Lila Dabill
Additionally, the first and second experiments produced approximately 20.10.4 Bq/Wskg and 10.80.8 Bq/Wskg of Ga, respectively. Recall from Sec. II that suppression of this isotope is desirable as the spectroscopic lines overlap strongly with Cu. From the first irradiation to the second irradiation, the isotopically purer sample reduced the production of Ga by a factor of nearly 2.
Experimental Test of a Process Upset in the EURO-GANEX Process and Spectroscopic Study of the Product
Published in Solvent Extraction and Ion Exchange, 2023
M. J. Carrott, C. J. Maher, C. Mason, M. J. Sarsfield, D. Whittaker, R. J. Taylor
Due to the low residual concentration of plutonium in AR1 the two final samples obtained under both normal and upset conditions were analyzed by α-spectrometry (Table 2). The recovery of plutonium in the extract contactors, based upon the activity of239/240Pu in the HAF and AR1 samples, exceeds 99.99% throughout the trial. The activity for 239/240Pu in AR1 remains at a low level under both normal and process upset conditions and shows that (the minimal) losses of plutonium to the aqueous raffinate are not affected by the low acid feed. Americium concentration in AR1 was also very low but due to interferences was not quantifiable by α-spectrometry. The aqueous profile sample showed that the americium content of the aqueous phase is significantly lower than 100 Bq/mL by the final stages of the extract contactor (i.e. >99.98% recovery). Therefore, americium has also not broken through into the aqueous raffinate.