Saturday, September 09, 2006


A university is an institution of higher education and research, which grants academic degrees at all levels bachelor, master, and doctorate in a variety of subjects. A university provides both tertiary and quaternary education. The word university is derived from the Latin universitas magistrorum et scholarium, roughly meaning community of masters and scholars.
Because of the above definition, there is some controversy regarding which is the world's oldest university.
If we consider a university as a corporation of students, then Plato's Academy is the first historically documented university. The original Latin word "universitas", first used at the time of renewed interest in Classical Greek and Roman tradition, tried to reflect this feature of Academy. If we consider university simply as a higher education institution, then it could be Shangyang, which was founded before the 21st c. BC in China, if it is not a just myth. In the western world, the choice is between Takshashila, Nalanda, Ratnagiri University and Al-Azhar University.

Friday, September 08, 2006

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.