Records of Gamma Radiation from the Ground and Beta Radiation from Radioactive Debris in Sweden, 1950-1955. Part I

Tellus ◽  
1956 ◽  
Vol 8 (2) ◽  
pp. 117-126 ◽  
Author(s):  
ROLF M. SIEVERT
Keyword(s):  
Gamma Radiation ◽  
Beta Radiation

scholarly journals Effect of Gamma or Beta Radiation on Salmonella DT 104 in Ground Pork†

2006 ◽  
Vol 69 (6) ◽  
pp. 1430-1433 ◽  
Author(s):  
KATHLEEN T. RAJKOWSKI ◽  
STEVEN E. NIEBUHR ◽  
JAMES DICKSON
Keyword(s):  
Gamma Radiation ◽  
Radiation Treatment ◽  
Meat Products ◽  
Fat Content ◽  
Beta Radiation ◽  
Pork Products ◽  
Radiation Sources ◽  
Significant Difference ◽  
Ground Pork ◽  
Pork Fat

Mixtures of six Salmonella Typhimurium DT 104 strains were inoculated into three ground pork products to determine the effect of fat content on the radiation resistance of Salmonella DT 104. The ground pork products were 90% lean, 50:50 fat:lean, and 100% fat. Inoculated products were irradiated using a gamma radiation source in a self-contained 137Cesium irradiator or a 10 MeV accelerator producing electrons (e-beam). The radiation D10-values (dose required for a 90% inactivation of viable CFU) for Salmonella DT 104 inoculated into 90% lean ground pork, 50:50 fat/lean ground pork, and 100% pork fat and subjected to beta radiation were 0.42 kGy, 0.43 kGy, and 0.43 kGy, respectively. The corresponding radiation D10-values for Salmonella DT 104 subject to gamma radiation were 0.56, 0.62, and 0.62 kGy, respectively. There was no statistical significant difference (P = 0.3) in radiation D10-values for Salmonella in the three products subject to either radiation treatment. Therefore, fat content had no effect. There was a significant difference (P = 0.001) between the radiation D10-values obtained with the two radiation sources. The radiation D10-values were within the reported range for irradiation destruction of Salmonella contaminated raw meat products.

scholarly journals THE EFFECT OF RADIOACTIVE RADIATIONS AND X-RAYS ON ENZYMES

1926 ◽  
Vol 9 (3) ◽  
pp. 309-313 ◽  
Author(s):  
Raymond G. Hussey ◽  
William R. Thompson
Keyword(s):  
Gamma Radiation ◽  
Fluid Layer ◽  
Beta Radiation ◽  
Sufficient Condition ◽  
X Rays ◽  
Dilute Solution ◽  
The Mean ◽  
Necessary And Sufficient ◽  
Reaction Speed

Evidence is presented which indicates: (1) that the effect of gamma radiation is negligible with respect to that of beta radiation upon pepsin in dilute solution under the conditions employed in the experiments made; (2) approximately the thickness of fluid layer which may be regarded as necessary and sufficient to practically completely absorb the available beta radiation; (3) that the mean reaction speed coefficient in radiochemical inactivation of pepsin varies inversely with the volume of solution irradiated if the thickness of the fluid layer satisfies the sufficient condition stated in (2), and beyond this as far as has been studied.

Cellular and Molecular Effects of Beta Radiation from I-131 on Human Tumor Cells a Comparison with Gamma Radiation

2014 ◽  
Vol 7 (2) ◽  
pp. 138-143 ◽  
Author(s):  
Chandan Kumar ◽  
Sundarraj Jayakumar ◽  
Badri Pandey ◽  
Grace Samuel ◽  
Meera Venkatesh
Keyword(s):  
Gamma Radiation ◽  
Tumor Cells ◽  
Human Tumor ◽  
Beta Radiation ◽  
Human Tumor Cells ◽  
Molecular Effects

scholarly journals Perspective technology of recycling of radioactive contaminated metal based on its melting

2018 ◽  
pp. 43-48 ◽  
Author(s):  
V. Balakin ◽  
V. Mashinistov ◽  
A. Koveria
Keyword(s):  
Gamma Radiation ◽  
Radiation Power ◽  
Beta Radiation ◽  
Volume Distribution ◽  
Effective Radiation Dose ◽  
Surface Distribution ◽  
Safety Criterion ◽  
The Individual ◽  
Effective Radiation ◽  
Melted Metal

Melting of the radioactively contaminated metal converts it as a source of ionizing radiation from a surface distribution of radionuclides into the source with their volume distribution. From the surface of the melted metal gamma radiation of a part of radionuclides is emitted, which are in its scope. Alpha and beta radiation are absorbed completely in the metal. To obtain a radiation-safe metal it is necessary that the amount of gamma-emitting radionuclides, which are loaded into the furnace together with the charge, did not exceed the established allowable level. The radiation safety criterion of the melted metal is the maximum value of the gamma radiation power from its surface, the established limit of the individual annual effective radiation dose is not exceeded. There is a need for experimental verification of theoretical results was obtained. The use of this technology will allow the return to industrial production of large amounts of accumulated radioactively contaminated metal and creates conditions for the prevention of environmental violations.

As mentioned in the previous chapter, many experiments on food irradiation in the 1950s were carried out with spent-fuel rods from nuclear reactors. Such fuel rods contain a mixture of many fission products, with greatly differing half-lives, emitting different types of radiation with different energies. The composition of fuel rods changes all the time because the radionuclides with short half-lives disappear quickly, whereas those with longer half-lives remain. Although fuel rods are primarily a source of gamma radiation (the less penetrating alpha and beta radiation are absorbed by the steel hull of the rods) they do give off some neutrons. Since the latter can produce radioactivity when they interact with matter such as food, fuel rods have not been used for irraditation of foods since the early 1960s. Because of their constantly varying composition, fuel rods also make dosimetry difficult, and this was another reason for abandoning their use. Individual constituents of spent fuel rods can be separated in reprocessing plants by chemical methods. One of the radionuclides obtainable in this way is Cs. With a half-life of 30 years and emission of gamma radiation (0.66 MeV) and beta radiation (0.51 MeV and 1.18 MeV), '^C s decays to stable '^B a (barium). After the ,37Cs is separated from the other constituents of the fission waste in the form of CsCl it is triply encapsulated in stainless steel containers because CsCl is soluble in water. If it leaked out it could cause contamination of the environment. As provided by the Waste Encapsulation and Storage Facility (WESF) at Hanford, Washington, the 137Cs capsule is 400 mm in active length (500 mm in total length) and 67 mm in diameter. There are only a few reprocessing plants in the world and the capacity for extracting ,37Cs from spent fuel rods is very limited. Plans for building several commercial reprocessing facilities in the United States were canceled by Presi­ dent Carter’s 1977 decision that the United States would not engage in commer­ cial reprocessing of spent nuclear fuel. As a consequence, not much ,37Cs is available and there are not many gamma radiation facilities which use ,Cs. No

1995 ◽  
pp. 31-31
Keyword(s):  
United States ◽  
Gamma Radiation ◽  
Spent Nuclear Fuel ◽  
Fission Products ◽  
The United States ◽  
Food Irradiation ◽  
Beta Radiation ◽  
Spent Fuel ◽  
Fuel Rods ◽  
Active Length

Radiation safety considerations for the bone seeking radiopharmaceuticals

2009 ◽  
Vol 48 (01) ◽  
pp. 37-43 ◽  
Author(s):  
A. Hoekstra ◽  
J. M. H. de Klerk ◽  
P. P. van Rijk ◽  
B. A. Zonnenberg ◽  
M. G. E. H. Lam
Keyword(s):  
Gamma Radiation ◽  
Radiation Safety ◽  
Area Under The Curve ◽  
Beta Radiation ◽  
Time Data ◽  
Rate Versus ◽  
Respective Contribution ◽  
Effective Doses ◽  
Safety Considerations ◽  
Measured Exposure

SummaryThe radiation exposure to bystanders from 89SrCl2, 186Re-HEDP and 153Sm-EDTMP, is generally thought to be caused by “bremsstrahlung” and gamma-radiation, with negligible contribution from beta-radiation. The latter assumption may be erroneous. The aim of this prospective study was the investigation of radiation safety after treatment with these radiopharmaceuticals. The radiation field around treated patients was characterized and the magnitude estimated. Patients, methods: 33 patients (30 prostate carcinoma, 3 breast carcinoma) were treated with 150 MBq 89SrCl2 (9 patients), 1295 MBq 186Re-HEDP (12 patients) or 37 MBq/kg 153Sm-EDTMP (12 patients). External exposure rates at 30 cm from the patient were measured at times 0 to 72 h post-injection. To evaluate the respective contribution of Bremsstrahlung, beta- and gamma-radiation, a calibrated survey meter was used, equipped with a shutter. For each patient, the measured exposure rate-versus-time data were fit to a curve and the curve integrated (area under the curve) to estimate the total exposure. Results: For 29/33 patients the total ambient equivalent doses (mean ± 1 standard deviation [SD]) based on the integral of the fitted curve were 2.1 ± 1.2 mSv for 89SrCl2, 3.3 ± 0.6 mSv for 186Re-HEDP and 2.8 ± 0.6 mSv for 153Sm-EDTMP. Beta-radiation contributes significantly to these doses ( >99% for 89SrCl2, 87% for 186Re-HEDP and 27% for 153Sm-EDTMP). The effective doses (at 30 cm) are < 0.1 mSv for 89SrCl2, 0.3 mSv for 186Re-HEDP and 1.6 mSv for 153Sm-EDTMP. Conclusion: Patients treated with 89SrCl2, 186Re-HEDP or 153Sm-EDTMP emit a spectrum of radiation, including non-negligible beta-radiation. With specific instructions effective doses to bystanders are acceptable.

scholarly journals Quantifying Biophoton Emissions From Human Cells Directly Exposed to Low-Dose Gamma Radiation

Dose-Response ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 155932582092676 ◽  
Author(s):  
Jason Cohen ◽  
Nguyen T. K. Vo ◽  
David R. Chettle ◽  
Fiona E. McNeill ◽  
Colin B. Seymour ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Single Photon ◽  
Photon Emission ◽  
Beta Radiation ◽  
Culture Vessel ◽  
Single Photon Detection ◽  
Cesium 137 ◽  
A Cell ◽  
Radiation Induced ◽  
Gamma Irradiated

Biophoton emission leading to bystander effects (BEs) was shown in beta-irradiated cells; however, technical challenges precluded the analysis of the biophoton role in gamma-induced BEs. The present work was to design an experimental approach to determine if, what type, and how many biophotons could be produced in gamma-irradiated cells. Photon emission was measured in HCT116 p53+/+ cells irradiated with a total dose of 22 mGy from a cesium-137 source at a dose rate of 45 mGy/min. A single-photon detection unit was used and shielded with lead to reduce counts from stray gammas reaching the detector. Higher quantities of photon emissions were observed when the cells in a tissue culture vessel were present and being irradiated compared to a cell-free vessel. Photon emissions were captured at either 340 nm (in the ultraviolet A [UVA] range) or 610 nm. At the same cell density, radiation exposure time, and radiation dose, HCT116 p53+/+ cells emitted 2.5 times more UVA biophotons than 610-nm biophotons. For the first time, gamma radiation was shown to induce biophoton emissions from biological cells. As cellular emissions of UVA biophotons following beta radiation lead to BEs, the involvement of cellular emissions of the same type of UVA biophotons in gamma radiation-induced BEs is highly likely.

Effects of sterilization modes on the mechanical strengths of plaster of paris implants

1989 ◽  
Vol 47 ◽  
pp. 890-891
Author(s):  
K. Cowden ◽  
B. Giammara ◽  
T. Devine ◽  
J. Hanker
Keyword(s):  
Gamma Radiation ◽  
Calcium Sulfate ◽  
Significant Loss ◽  
Potassium Sulfate ◽  
Limiting Factors ◽  
Radiation Sterilization ◽  
Plaster Of Paris ◽  
Hardness Tester ◽  
Dry Heat ◽  
Calcium Sulfate Hemihydrate

Plaster of Paris (calcium sulfate hemihydrate, CaSO4. ½ H2O) has been used as a biomedical implant material since 1892. One of the primary limiting factors of these implants is their mechanical properties. These materials have low compressive and tensile strengths when compared to normal bone. These are important limiting factors where large biomechanical forces exist. Previous work has suggested that sterilization techniques could affect the implant’s strength. A study of plaster of Paris implant mechanical and physical properties to find optimum sterilization techniques therefore, could lead to a significant increase in their application and promise for future use as hard tissue prosthetic materials.USG Medical Grade Calcium Sulfate Hemihydrate Types A, A-1 and B, were sterilized by dry heat and by gamma radiation. Types A and B were additionally sterilized with and without the setting agent potassium sulfate (K2SO4). The plaster mixtures were then moistened with a minimum amount of water and formed into disks (.339 in. diameter x .053 in. deep) in polyethylene molds with a microspatula. After drying, the disks were fractured with a Stokes Hardness Tester. The compressive strengths of the disks were obtained directly from the hardness tester. Values for the maximum tensile strengths σo were then calculated: where (P = applied compression, D = disk diameter, and t = disk thickness). Plaster disks (types A and B) that contained no setting agent showed a significant loss in strength with either dry heat or gamma radiation sterilization. Those that contained potassium sulfate (K2SO4) did not show a significant loss in strength with either sterilization technique. In all comparisons (with and without K2SO4 and with either dry heat or gamma radiation sterilization) the type B plaster had higher compressive and tensile strengths than that of the type A plaster. The type A-1 plaster however, which is specially modified for accelerated setting, was comparable to that of type B with K2SO4 in both compressive and tensile strength (Table 1).

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