Radioactivity other applications

Cesium is used as a getter in electron tubes. Other applications are in photoelectric cells ion propulsion systems heat transfer fluid in power generators and atomic clocks. The radioactive Cs-37 has prospective applications in sterilization of wheat, flour, and potatoes. 

The metal has very little commercial use. In elemental form it is a laser source, a portable x-ray source, and as a dopant in garnets. When added to stainless steel, it improves grain refinement, strength, and other properties. Some other applications, particularly in oxides mixed with other rare earths, are as carbon rods for industrial hghting, in titanate insulated capacitors, and as additives to glass. The radioactive isotope ytterbium-169 is used in portable devices to examine defects in thin steel and aluminum. The metal and its compounds are used in fundamental research. 

Extraordinary binding specificity is used in diagnostic tests targeted transport of drugs, toxins, or radioactive compounds to tumors as a cancer therapy many other applications. 

Adsorption of Radionuclides. Other applications that depend on physical adsorption include the control of krypton and xenon radionuclides from nuclear power plants (92). The gases are not captured entirely, but their passage is delayed long enough to allow radioactive decay of the short-lived species. Highly microporous coconut-based activated carbon is used for this service. 

E. P. Horwitz and W. Schulz, in L. Cecille, M. Casarci, and L. PietneUi, eds., New Separation Chemistry Techniquesfor Radioactive Waste and Other Applications, Elsevier Applied Science, New York, 1990, pp. 21—30. 

Other Applications. Many applications of adsorption involving radioactive compounds simply parallel similar applications involving the same compounds in nonradio active forms, eg, radioactive carbon-14, or deuterium- or tritium-containing versions of C02, H20, hydrocarbons. For example, molecular sieve zeolites are commonly employed for these separations, just as tor the corresponding nonradio active uses. 

Peptides, for example, are needed for the production of antibodies and for epitope mapping proteins can be produced in radioactively labelled forms by in vitro translation for studies of protein-protein interactions and other applications. In vitro protein synthesis is a technique that can be readily carried out in any biochemistry laboratory, whereas peptide synthesis, like peptide sequencing, is a specialist technique using dedicated equipment, which is nowadays routinely automated. 

Large amounts of gold are still used in the manufacture of coins, medals, jewelry, and art. Gold also has a number of uses in industry, medicine, and other applications. For example, one radioactive isotope of gold is commonly used to treat cancer. 

Two radioactive isotopes of sodium— sodium-22 and sodium-24— are used in medicine and other applications. They can be used as tracers to follow sodium in a person s body. A tracer is a radioactive isotope whose presence in a system can easily be detected. The isotope is injected into the system at some point. Inside the system, the isotope gives off radiation. That radiation can be followed by means of detectors placed around the system. 

The use of glass is not restricted to the cases mentioned above. Among other applications, mention can be made of those in nuclear technology (protection from radiation, immobilization of radioactive waste by fusion into a chemically resistant glass, etc.), in agriculture (as carrier for fertilizers with long-term effects) and a number of possible applications in electronics (cf., for example, the survey paper by McMillan, 1976). A separate chapter is devoted to the so-called glass-ceramics. 

In the Moore and Sharp19 procedure outlined below a radioactive phosphate is inserted at the junction by labelling the 3 -RNA using T4 polynucleotide kinase and [y-32P]ATP, but the ligation approach is useful for many other types of modifications. Other applications include ... 

EPA Environmental standards for management and storage of spent nuclear fuel, high-level and transuranic radioactive wastes —applicability and definitions Whole body Thyroid Other critical organs 25 mrem 75 mrem 25 mrem EPA 2001 i 40CFR191, Subpart A... 

Metallic americium has a face-centered cubic structure at its melting point and a double hexagonal closed-packed structure at temperatures below its melting point. The isotope americium-241 emits a-particles and y-rays in its radioactive decay, and is a source of y-radiation, used to measure the thickness of metals, coatings, degree of soil compaction, sediment concentration, and so on. The same isotope, mixed with beryllium, is used as a neutron source in oilwell logging and other applications. Americium-241... 

The minimum detectable activity (MDA) is the smallest net count that can be reported with a certain degree of confidence that represents a true activity from a sample and is not a statistical variation of the background. The term MDA is not universally acceptable. In the general case, in measurements not necessarily involving radioactivity, other terms such as lowest detection limit have been used. Here, the notation and applications will be presented with the measurement of a radioactive sample in mind. 

The solid-state chemical, optical, and physical properties of the RE, Y, and Sc orthophosphates have been extensively investigated by means of numerous techniques. Such studies include optical spectroscopy (Trukhin and Boatner 1997), x-ray absorption (Shuh et al. 1994), electron paramagnetic resonance (EPR) spectroscopy (Abraham et al. 1981, Boatner et al. 1981b), Mossbauer (Huray et al. 1982), Rutherford backscattering (Sales et al. 1983), and other techniques. Additionally, scanning ellipsometry has been used by Jellison and Boatner (2000) to determine the spectroscopic refractive indices of the xenotime-structure RE orthophosphates. The extensive range of studies of these orthophosphates was motivated initially by the potential application of the orthophosphates to radioactive waste disposal and subsequently by the other applications... 

In 1940, Hamilton and associates in Los Angeles and Hertz and his associates in Boston were the first to measure the uptake of radioactive iodine-128 by the thyroid. This made it possible to diagnose patients with increased or decreased thyroidal function. The names, hyper- and hypothyroidism, reflected the functional basis of the diagnosis. The use of radioiodine to define thyroid disease led to the search for other applications of the radioactive tracer principle. 

Radiochemical methods of analysis are used in a wide range of analytical applications. Not only can these methods be used to obtain information regarding the nature and quantities of substances present in materials of interest, but radioactive elements can also be employed as tracers to study various physicochemical processes. Radioactive substances can be used to follow the movement of elements or of specific compounds in soils and plants, the absorption of elements in the body, and the selfdiffusion of lead atoms in metallic lead, among other applications. Although these tracer applications are of great practical value, the present chapter will be concerned only with applying radioactivity to determining the presence and quantity of elements and compounds in various materials—that is, the use of radioactivity in chemical analysis. 

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