pertaining to the bile, to the bile ducts, or to the gallbladder. biliary catheter (biliary decompression catheter) a catheter inserted via a skin incision through the liver and common bile duct into the duodenum.
Not all of the atoms of a radioisotope decay at the same time, but they decay at a rate that is characteristic to the isotope. The rate of decay is a fixed rate called a half-life. The half-life of a radioisotope describes how long it takes for half of the atoms in a given mass to decay.
Other forms of Radiometric Dating. Carbon 14's half-life is not nearly long enough to measure dates in the geological past. For that elements with a half life of many millions of years are required. Here are the half-lives of some other radioactive elements: 1  Uranium-238 ~half life=4.5 billion years. 2  Uranium-235 ~half life=704 million years.