By default sorting is in ascending order. Collections.sort(list); method sort the list items in ascending order. Collections.reverse(list); method sort the list items in descending order. Same as you can sort the arrays also, Let refer the below code snippet, which sort the string array contains name of cities.orting using Comparator. Let have look to sort Employee list using implementation of Comparator interface. If you want to sort object other than their natural ordering at that time we use Comparator.
Thallium is a soft, malleable gray metal that was previously widely used in rat poisons and insecticides. Thallium itself and compounds containing the element are highly toxic. It is particularly dangerous because compounds containing thallium are colorless, odorless, and tasteless.hallium is a soft, malleable gray metal that was previously widely used in rat poisons and insecticides. Thallium itself and compounds containing the element are highly toxic. It is particularly dangerous because compounds containing thallium are colorless, odorless, and tasteless.
203 Tl and 205 Tl are the only stable isotopes and 204 Tl is the most stable radioisotope with a half-life of 3.78 years. Thallium-202 (half life 12.23 days) can be made in a cyclotron while thallium-204 (half life 3.78 years) is made by the neutron activation of stable thallium in a nuclear reactor. The lead-201 can be produced in a cyclotron by the bombardment of thallium with protons or deuterons by the (p,3n) and (d,4n) reactions. 2  combined with sulfur or selenium and arsenic, thallium has been used in the production of high-density glasses that have low melting points in the range of 125 and 150 Â°C.