1. Petroleum refinery process in which large heavy oil molecules are broken down into smaller ones. If conducted only with the application of heat, it is called thermal cracking. If a catalyst is also used, it is called catalytic cracking. If hydrogen is used in addition to heat and catalysts, it is called hydrocracking. 2. Deciphering of a code or encrypted data.
Vitamin D3 is the form of vitamin D called cholecalciferol. Cholecalciferol is the most widely known of the vitamin D series and is a fat soluble vitamin that is stored to some degree in the body. It is used as a dietary supplement and for the treatment and prevention of vitamin D deficiency.
Typically, the prescription form is Vitamin D2, also known as ergocalciferol. The over-the-counter Vitamin D is usually Vitamin D3, also referred to as cholecalciferol. Prescription strength Vitamin D usually comes in 50,000 units. The over-the-counter Vitamin D usually comes in doses of 400 - 1000 units.: The vitamin D that is prescription and is 50,000 IU is vitamin D2 (ergocalciferol). The over-the-counter vitamin D is vitamin D3 (cholecalciferol). Each is absorbed differently by the body and therefore they have different bioequivalence.