Cobalt-60, radiation from

An extractive study of one can enamel in the presence of food-simulating solvents to determine how gamma radiation from a cobalt-60 source altered the nature and amount of extractives of this enamel. 

Gamma knife A device that uses multiple converging beams of gamma radiation from cobalt-60 to highly focus radiation on small tumors within the brain. 

Protection Against Radiations from Radium, Cobalt-60 and... 

CobaltCII) iodide, uses, 7 240t CobaltCII) ion, 7 229 CobaltCIII) ion, 7 229 Cobalt isotopes, residual radiation from, 17 553-554... 

The results from similar clonogenic survival studies with an [ At]-IgG monoclonal antibody to human leukemia cells 158) have given a mean Dq of 12 At atoms cell the RBE has been determined as approximately 4, when compared to the y-radiations from cobalt-60 13). A range of RBE values (2.8-S.2) for At a-particles compared with other low-LET (y,/ ) radiations has been obtained for a variety of tissues under different in vitro and in vivo experimental conditions 12, 13, 29, 61, 64). 

Systems using either gamma radiation from cobalt 60 or electron beams have been used for vulcanization. The electron beam method has been used for curing silicone rubbers. 

Synthesis of ethyl bromide from hydrogen bromide and ethylene, using G -radiation from cobalt-60. 

T.D. Phillips, Effect of Gamma Radiation from Cobalt 60 on the Mechanical Properties of AHH and ARP Double-Base Solid Propellants , NPP TMR-159, Naval Powder Factory, Indian Head... 

Impulseless resonance absorption of y-quants (gamma radiation) from a radioactive isotope, here Cobalt 57Co 57Fe + y (main quant 122 keV quant used for spectroscopy has a different energy)... 

Confluent cultures containing (2 X 106 cells/90 mm dish are irradiated with 4000-6000 rads of y-radiation from a cobalt source. Irradiation should last for less than 1 min and a variety of cell lines (e.g. HeLa, BHK21/C13 or 3T3) are suitable (Puck et al., 1956). These cells may be used directly or may be trypsinised into smaller vessels. They may appear healthy for up to 4 weeks but do not divide. 

The nuclear industry makes available about 3000 nuclides, including both the stable and the radioactive nuclides. Approximately 50 radioactive nuclides, along with some stable nuclides that have been isotopically enriched, are essential in research, medical, and industrial applications. Many of these are now produced commercially, but several still are dependent on government facilities. Some, for economic reasons, come from other countries. Radiation processing for sterilization of disposable medical supplies is an important operation using cobalt-60 from Canada. Electron accelerators have replaced... 

The medical applications of nuclear technology range from in vitro and in vivo injections for diagnostic tests to cobalt radiation for cancer therapy. A new medical specialty was created, a family of compact cyclotrons was developed to provide short-lived nuclides, and a sizable industry evolved to produce technetium. Until the nuclear industry was created, technetium had been missing from the chart of chemical elements because the half-life of the most stable member was too short, 21,000 years. Technetium and several other nuclides of importance here are discussed elsewhere in the chapter in connection with their production (see Table 21.19).60,61... 

The emulsion polymerization of vinyl chloride, initiated by gamma radiation from a Cobalt-60 source, has been studied in detail. Good conversions to high yields were obtained. 

A growing use of cobalt-60 is in food irradiation. Food irradiation is a method for preserving food. The food is exposed to radiation from cobalt-60. That radiation kills bacteria and other organisms that cause disease and spoilage. The food can be stored longer without going bad after being irradiated. 

The use of cobalt radiation treatments for cancerous tumors was described in Example 26-3. Several other nuclides are used as radioactive tracers in medicine. Radioisotopes of an element have the same chemical properties as stable isotopes of the same element, so they can be used to label the presence of an element in compounds. A radiation detector can be used to follow the path of the element throughout the body. Modern computer-based techniques allow construction of an image of the area of the body where the radioisotope is concentrated. Salt solutions containing "iNa can be injected into the bloodstream to follow the flow of blood and locate obstructions in the circulatory system. Thallium-201 tends to concentrate in healthy heart tissue, whereas technetium-99 concentrates in abnormal heart tissue. The two can be used together to survey damage from heart disease. 

Microscopic examination of a hardened 1.0 percent carbon steel shows no undissolved carbides. X-ray examination of this steel in a diffractometer with filtered cobalt radiation shows that the integrated intensity of the 311 austenite line is 2.33 and the integrated intensity of the unresolved 112-211 martensite doublet is 16.32, both in arbitrary units. Calculate the volume percent austenite in the steel. (Take lattice parameters from Fig. 12-5, A/corrections from Fig. 13-8, and temperature factors from Fig. 4-20.)... 

Gamma radiation from cobalt-60 can be used to irradiate food to keep it from spoiling. 

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