Internal Examination of a Newly Hatched Alligator. A professional can determine the gender of a very small baby alligator, 6 to 10 inches long. One method is to place the creature on its back and hold open his vent with round-tipped tweezers or forceps, with a helper's assistance.
Technetium is the only element below uranium that does not exist on Earth. It is a synthetic (man-made) element produced in a particle accelerator. For many years, chemists knew that an element with atomic number 43 must exist, based on an empty spot in the periodic table.
Technetium-99 is used as a gamma ray-free source of beta particles. Long-lived technetium isotopes produced commercially are by-products of fission of uranium-235 in nuclear reactors and are extracted from nuclear fuel rods.he most stable radioactive isotopes are technetium-98 with a half-life of 4.2 million years (Ma), technetium-97 (half-life: 2.6 Ma) and technetium-99 (half-life: 211,000 years). Thirty other radioisotopes have been characterized with mass numbers ranging from 85 to 118.