Radionuclides strontium

These results are consistent with laboratory measurements of the effects of pH and oxidation state on the leachability of nuclear fuel particles (Kashparov et al, 2000). The increased leachability of the oxidized fuel particles may be due to (i) an increased solubility because of the change in oxidation state (ii) the higher surface area of the highly fractured oxidized particles or (iii) the diffusion of radionuclides (strontium, caesium) to grain boundaries and particle surfaces during the heating and oxidation process. 

Rabbit brush, on the other hand, had the highest levels for three of the six contaminants (manganese-54, beryllium-7, and tritium). This is consistent with studies conducted by Fresquez et al. [31], which demonstrated that rabbit brush tends to readily take up radionuclides (strontium-90 and uranium) in contaminated sites. While salt cedar and rabbit brush are perennials and sweet clover is an annual, there did not appear to be a clear correlation between the accumulation of contaminants in these plants and their life cycle. Again, this study emphasizes the importance of taking into account all the factors that might influence the radionuclide concentrations within a honey bee. 

Sr, as the strontium ion (Sr2+), is used for pain palliation in patients with metastatic bone disease. The strontium ion is a calcium ion mimic, being taken up in metabolically active bone such as cancer. 89Sr is a therapeutic radionuclide with a half-life of 50.53 days, emitting a 1.49 MeV [3 particle on decay. Several recent reviews discuss the use of radionuclides and their complexes as pain palliation agents in metastatic bone disease.18,212-215... 

Keywords phytoremediation, radionuclides, 137-caesium, 90-strontium, 125-iodine, uranium, radium, uranium mill tailings, biomonitoring... 

Researchers at BNL claim that this technology may be used to extract metals such as cadmium, arsenic, lead, zinc, copper, magnesium, manganese, aluminum, barium, nickel, and chromium, as well as radionuclides such as uranium, thorium, plutonium, cobalt, cesium, and strontium. They state that the process offers the following advantages ... 

The lonsiv ion exchange resins are extraction technologies used to separate radionuclides from alkaline wastewater in the presence of competing cations. These resins include lonsiv IE-910 and lonsiv IE-911, which are manufactured using a new class of crystalline silicotitanates (CSTs) invented by researchers from Sandia National Laboratory (SNL) and Texas A M University. CSTs demonstrate high distribution coefficients in acidic, neutral, and alkaline solutions with high concentrations of competitive ions such as sodium and potassium. The affinity of CSTs for strontium in neutral or alkaline wastes is also high. 

UOP molecular sieves (UOP) has developed the lonsiv family of ion exchange resins for the extraction of radionuclides from wastewater. lonsiv TIE-96 is composed of a titanium-coated zeolite (Ti-zeolite) and is used to separate plutonium, strontium, and cesium from alkaline supernatant and sludge wash solutions. The technology was developed by Pacific Northwest Laboratory (PNL) for use at the West Valley, New York, nuclear waste facility. The technology is commercially available. 

The Sr-82 used in these studies was produced by spallation of a molybdenum target with 800 MeV protons at the Los Alamos Meson Physics Facility (LAMPF) and radiochemically separated by the Nuclear Chemistry Group at Los Alamos Scientific Laboratory (LASL) (22). The major radionuclidic contaminant in the Sr-82 is Sr-85 which is present in at least 1 1 ratio relative to Sr-82. The actual ratio depends upon the length of time after the production of radioactive strontium. Because of the 65 day half life of Sr-85 and the 25 day half life of Sr-82, the Sr-85 Sr-82 ratio increases with time. Other radionuclides found by the Hammersmith group in the processed Sr-82/85 shipment were Sr-89 ( 1%), Sr-90 ( 0.01%), Co-58 ( 1%) and Rb-84 ( 1%) from (17). 

No radionuclidic contaminants of other elements have been observed in the shipped material. Of course, Sr-85 is always present and Sr-83 is present at short intervals after the irradiation. The presence of Sr-83 in the product leads to the formation of Rb-83 in the eluant from the generator. Large quantities of Sr-85 cause problems in shielding the generator. Inspection of the production data allows one to make the following characterizations of the strontium product a) for short irradiations ( 200 hours), the 82/85 ratio at EOB averages approximately 1.4 and the... 

Figure 4. Change in ratios versus time after EOB for the strontium isotope ratios 82 85 and 83 82. "Limit" refers to the radionuclidic requirements listed in Table III.

Radionuclidic analyses are performed with either a lithium-drifted germanium or intrinsic germanium detector. The assay for Sr-82 is based upon its 777 keV photon of 13.6% abundance. Strontium-85, which is often present in amounts comparable to that of Sr-82, is assayed by its 514 keV photopeak, which must be resolved from prominent 511 keV annihilation radiation by a curve stripping procedure (12). 

During the winters of 1966-1967 and 1967-1968, cyclonic storms occurred over the California coast on three occasions shortly after the detonation of a nuclear weapon on the China mainland such that measurable concentrations of 12.8-day 140Ba were present in 6-hour rainfall samples. The deposition radioactivity ratios of 140Ba, 89Sr, and 90Sr were examined in the rainfall along the California coast for each of these three storms and used to examine the fractional contribution of the longer lived strontium radionuclides from the various known Chinese nuclear explosions. 

The radionuclides commercially available and most commonly used for a number of the foregoing applications include anhmony-125 banum-133, 207 bismuth-207 bromine-82 cadmium-109, 115 m calcium-45 carbon-14 cerium-141 cesium-134, 137 chlorine-36 chromium-51 cobalt-57, 58, 60 copper-64 gadolimum-153 germanium-68 gold-195. 198 hydrogen-3 (tritium) indium-111, 114 m iodine-125, 129, 131 iron-55, 59 krypton-85 manganese-54 mercury-203 molvbdenum-99 nickel-63 phosphorus-32. 33 potassium-42 promethium-147 rubidium-86 ruthenium-103 samarium-151 scandium-46 selenium-75 silver-110 m sodium-22, strontium-85 sulfur-35 technetium-99 thallium-204 thulium-171 tin-113, 119 m, 121 m. titamum-44 ytterbium-169, and zinc-65. 

Galkin, B.Ya., Shishkin, D.N. 2001. Extraction withdrawal of cesium and strontium radionuclides from the solution of spent nuclear fuel. In Back-End of the Fuel Cycle From Research to Solutions. GLOBAL 2001, September 9-13, Paris, France. 

After a few years of storage, the main radioactive heat emitters in HLW are 90Sr and 137Cs. In addition, extremely long-lived actinides—neptunium, plutonium, americium, and curium—should be collected for transmutation in the future. Therefore, different flowsheets can be proposed for waste processing. It is possible to extract each radionuclide in the special extraction (sorption) cycle, for example, uranium and plutonium in the PUREX process, and after that, minor actinides (MAs) by the TRUEX process,4 strontium by the SREX process,5,6 and cesium by sorption7 or extraction.8... 

There are special extractants to extract each class of radionuclides crown ethers for cesium and strontium and phosphine oxides, carbamoylmethylphosphine oxides, and diamides for actinides, etc. It is unrealistic to have a single extractant that can extract all target nuclides with nearly the same effectiveness. So, a promising technical decision is to mix extractants for different radionuclides and extract them simultaneously. 

CCD and its brominated analog (Br-COSAN) are very widely studied as potential components of extraction mixtures for radionuclide separation. These compounds were proposed for extraction more than 30 years ago,17 and already in the first publications, polyethylene glycols (PEGs) were used for simultaneous extraction of cesium and strontium. An excellent review of extraction by carborane compounds was recently published 18 so, in this paper, mainly works published after 2003 and not included in the previous review will be discussed. 

Luther, T.A., Herbst, R.S., Peterman, D.R., Tillotson, R.D., Gam, T.G., Babain, V.A., Smirnov, I.V., Stoyanov, E.S., Antonov, N.G. Some aspects of fundamental chemistry of the Universal Extraction (UNEX) process for the simultaneous separation of major radionuclides (cesium, strontium, actinides, and lanthanides) from radioactive wastes. J. Radioanal. Nucl. Chem. (2006), 267 (3), 603-613. 

Kremliakova, N. Y., Novikov, A. P, and Myasoedov, B. F., Extraction chromatographic separation of radionuclides of strontium, cesium, and barium with the use of tvex-dchl8c6, J. Radioanal. Nucl. Chem. Lett., 145, 23-28, 1990. 

Freundlich constants and ranges of Kd values for radionuclide sorption on the Rattlesnake Ridge sandstone are given in Table III. The constants K and N were calculated using linear regression. Linear sorption isotherms (N = 1.0) are observed only for strontium, selenium, and radium. 

Chemical components in the waste solutions potentially could affect radioelement solubility and sorption reactions, and thus enhance or reduce radionuclide transport. The effects of 12 chemical components on the solubility and sorption of cobalt, strontium, neptunium, plutonium, and americium were studied to... 

The anthropogenic radionuclides of most concern are those produced as fission products from nuclear weapons and nuclear reactors. The most devastating release from the latter source to date resulted from the April 26, 1986, explosion, partial meltdown of the reactor core, and breach of confinement structures by a power reactor at Chernobyl in the Ukraine. This disaster released 5 x 107 Ci of radionuclides from the site, which contaminated large areas of Soviet Ukraine and Byelorussia, as well as areas of Scandinavia, Italy, France, Poland, Turkey, and Greece. Radioactive fission products that are the same or similar to elements involved in life processes can be particularly hazardous. One of these is radioactive iodine, which tends to accumulate in the thyroid gland, which may develop cancer or otherwise be damaged as a result. Radioactive cesium exists as the Cs+ ion and is similar to sodium and potassium in its physiological behavior. Radioactive strontium forms the Sr2+ ion and substitutes for Ca2+, especially in bone. 

Domanski T, Liniecki J, Wtkowska D. 1969. Kinetics of calcium, strontium, barium, and radium in rats. In Mays CW, Jee WSS, Lloyd RD, et al, eds. Delayed effects of bone-seeking radionuclides. Salt Lake City, UT University of Utah Press, 79-94. 

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