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.
Best Answer: Silicon is used to make many electronic devices, such as transistors, integrated circuits, computer chips and solar cells because it is a good semiconductor. Silicon, when doped with boron, gallium, phosphorus, or arsenic is used for transistors, solar cells, and other electronic devices. Silicon is commonly used around high temperatures because of its high melting point. It is used to make concrete and bricks, as a lubricant and for silicone implants (plastic/reconstructive surgery). Silicon plastic (Silastic) is used for artificial skin grafts to protect healing skin. Silicones are products of silicon, made by hydrolyzing a silicon organic chloride. Silica (sand) is the main ingredient of glass, and is also found in the human skeleton.