You may need a backup method of birth control if you have vaginal intercourse during the seven days after a missed pill. Some backup methods are the condom, female condom, diaphragm, or sponge. You can also use emergency contraception (morning after pill) up to five days after unprotected intercourse.
Strontium-90, a radioactive isotope, is a by-product of nuclear reactors and present in nuclear fallout. It has a half-life of 28 years. It is absorbed by bone tissue instead of calcium and can destroy bone marrow and cause cancer. However, it is also useful as it is one of the best high-energy beta-emitters known. It can be used to generate electricity for space vehicles, remote weather stations and navigation buoys.
Scandium Uses. Scandium is a transition metal element, which was discovered in 1879. It has since found various applications in different fields. Find out more about its uses, and also some interesting facts about this metal, in this article.candium-46, which is a radioactive isotope of the element, is used in oil refineries, where it plays the role of a tracing agent. The compound scandium triflate acts as a catalyst in organic chemistry. Scandium can also be used for the purpose of polishing glass.