Friday, December 28, 2007

Cast iron

Cast iron usually refers to grey cast iron, but can mean any of a group of iron-based alloys containing more than 2% carbon. It is made by remelting pig iron, often along with substantial quantities of scrap iron and scrap steel, and taking various steps to remove undesirable contaminants such as phosphorus and sulfur. Carbon and silicon content are reduced to the desired levels, which may be anywhere from 2% to 3.5% for carbon and 1% to 3% for silicon depending on the application. Other elements are then added to the melt before the final form is produced by casting.
Iron is most commonly melted in a small blast furnace known as a cupola. After melting is complete, the molten iron is removed or ladled from the forehearth of the blast furnace. This process is thought to have been devised by the late 18th century ironmaster John Wilkinson, whose innovative ideas revolutionized the field of metallurgy. Previously, iron was melted in an air furnace, which is a type of reverberatory furnace.

Monday, December 17, 2007


In finance, a bond is a debt security, in which the certified issuer owes the holders a debt and is obliged to repay the principal and interest (the coupon) at a later date, termed maturity. Other conditions may also be attached to the bond issue, such as the obligation for the issuer to provide certain information to the bond holder, or limits on the behavior of the issuer. Bonds are usually issued for a fixed term more than ten years, U.S. Treasury securities issue debt with life of ten years or more, which is a bond, and New debt between one year and ten years is a "note", and new debt less than a year is a "bill".

Sunday, December 02, 2007

Antoine Lavoisier

Antoine Lavoisier was one of the well known French scientists and was a chief government official. His theories of combustion, his growth of a way to categorize the fundamentals and the first new textbook of chemistry led to his being known as the father of modern chemistry. He contribute too much of investigate in the field of chemistry. He is quote for saying, nothing is lost, nothing is created, and everything is distorted. He bore in Paris, France on Aug. 26, 1743. When he was eleven years old he attends a college called Mazain, For Lavoisier's last two years in college he creates a massive deal of attention in science.
He received an excellent teaching and developed an attention in all branches of science, particularly chemistry. Abbe Nicolas Louis de Lacaill trained Lavoisier regarding meteorological examination. On 1763 Lavoisier anticipated his bachelor's degree and on 1764 a licentiate which allowed him to practice his profession. In his extra time he studied books of science and his first paper was written about gypsum, also familiar by hydrated calcium sulfate and he describes its chemical and physical property.