Yttrium-90 and

Available forms A mixture containing strontium-90, yttrium-90, and strontium-89 chlorides in hydrochloric acid solution also as the carbonate and tita-nate. 

Radioactive decay is first order in the decaying isotope. For example, strontium-90 contained in fallout from nuclear explosions decays to yttrium-90 and a beta particle. Write the rate law for the decay of strontium-90. 

The system strontium 90/yttrium 90 and strontium 89 can also be separated... 

Similar reactivity is observed in the cyclization of enynes in the presence of the yttrium-based catalyst 70 and a silane reductant [53,54]. The 1,6- and 1,7-enynes 90 and 91 provide -E-alkylidene-cyclopentancs 92 and -cyclohexanes 93 in very good yield (Eq. 15, Scheme 20) [55]. These transformations likely proceed by syn hydrometallation of the 7r-basic alkyne, followed by insertion of the alkene and a-bond metathesis. The reaction of 1,6-enynes tolerated... 

Iodine-131 was among the first radioactive isotopes used for radioimmunoconjugate preparation (Order, 1982 Regoeczi, 1984). Since the earliest studies on the efficacy of radiotherapy, additional isotopes have been employed, such as iodine-125, bismuth-212, yttrium-90, yttrium-88, technetium-99 m, copper-67, rhenium-188, rhenium-186, galium-66, galium-67, indium-111, indium-114 m, indium-115, and boron-10. 

Treatment of patients with relapsed or refractory low-grade, follicular, or transformed B-cell non-FIodgkin s lymphoma, including patients with Rituximab (Rituxan) refractory follicular non-Flodgkin s lymphoma. The therapeutic regimen includes Rituximab, Indium-111 Ibritumomab Tiuxetan, and Yttrium-90 Ibritumomab Tiuxetan... 

Shimoni A, Zwas ST, Oksman Y, Hardan I, et al. 2007. Yttrium-90-ibritumomab tiuxetan (Zevalin) combined with high-dose BEAM chemotherapy and autologous stem cell transplantation for chemo-refractory aggressive non-Hodgkin s lymphoma. Exp Hematol. 35 534-540. 

Kramer, G. H. and Davies, J. M., Isolation of strontium-90, yttrium-90, promethium-147, and cerium-144 from wet ashed urine by calcium oxalate coprecipitation and sequential solvent extraction, Anal. Chem., 54, 1428-1431, 1982. 

A catalytic asymmetric epoxidation reaction of a,/l-unsaturated esters via conjugate addition of an oxidant using chiral yttrium-biphenyldiol-Ph3As=0 complexes has been developed. Yields up to 90% and ees up to 99% have been achieved.43... 

Calculation of the 90Sr concentration from yttrium precipitation and 90 Y counting data... 

Akaboshi M, Noda M, Kawai K et al (1979) Asymmetrical radical formation in d- and L-alanines irradiated with yttrium-90 P-rays. Orig Life Evol Biosph 9 181-186... 

Another approach is to use kit formulations also for this kind of product. Therapeutic radiopharmaceuticals have been developed where the carrier molecule is formulated in a lyophilized kit and supplied together with the radionuclide. An example of this is the MAb ibritumomab tiuxetan formulated for labeling with the P-emitting radionuclide 90Y. Yttrium-90 ibritumomab tiuxetan (Zevalin) is used in the treatment of non-Hodgkin s lymphoma (NHL). 

Tin from cans, concrete, glass, aluminum, and plastic wrapping materials Yttrium -90... 

K later they determined that the drop was a fluke, that subtle shifts in resistance in the contacts between the electrical leads and the sample, and not in the sample itself, were responsible. Sumitomo Electric Industries of Japan came in with 300° K (no confirmation]. In Michigan, researchers at Energy Conversion Devices announced that part of a synthetic material made of fluorine (a highly dangerous yellow gas), yttrium, barium, and copper oxide had superconducted at 45° to 90° F. (The part that super-conducted, it turned out, represented less than 1 percent of the material tested, and the samples were far too small to lose all resistance. It is incredibly difficult to identify the exact portion of any material that shows superconductivity and then produce a pure sample of it.) In New Delhi, at the National Physical Laboratory, scientists saw evidence of superconductivity in material heated to 80° F, but the electrical signals were misleading, an artifact of the measurement process. 

Preparation and use of DTPA-coupled antitumor antibodies radiolabelled with yttrium-90. In Antibody-Mediated Delivery Sytems, Hnatowich, D.J., Snook, D., Rowlinson, G., Stewart, S., Epentos, A.A., Eds. Marcel Dekker, Inc. New York, 1988 353-374. 

One radioactive isotope of yttrium, yttrium-90, has some important practical applications. The isotope is combined with other substances to produce smart drugs. Smart drugs are drugs that detect, attack, and destroy only certain, very specific kinds of cells, such as those found in cancerous tissue. One advantage of using yttrium-90 is that it is easy to obtain. It is produced when another radioactive isotope (strontium-90) breaks down. Strontium-90 is a by-product of nuclear reactions that occur in nuclear power plants. 

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