Monthly Archives: October 2016

What is a Semiconductor?

“Semi-conductors,” also known as integrated circuits (ICs) or chips, are components with more electrical conductivity than insulators, but less electrical conductivity than conductors, as measured by the potential activity of charged electrons. They are ubiquitous in our society: anything with an ON/OFF switch contains an integrated circuit. Metalloid elements such as the abundant silicon (Si) are used as the chips’ substrate. When manufactured, impurities are deliberately added (a process called “doping”) to alter the conductivity characteristics, making them more suitable as electronic-device components. Common dopants are arsenic or boron, each with a different quantity of outer electrons that create positive or negative charges and electron “holes.” In a move away from electronic technologies such as vacuum tubes and crystal diodes in 1958, semiconductor components have allowed companies to continually

Centrifugation is one of the most widely used laboratory techniques for the separation of materials in the fields of biochemistry, molecular biology, medicine, food sciences and industry. It’s all about gravity and mass: particles in a heterogeneous solution will, given enough time, separate based on their size and density. Smaller, less-dense particles may also migrate down, but not always; some particles will never settle, but remain suspended in solution. Centrifuges force this process along much more quickly and efficiently. Its uses have proven to be so powerful and wide-spread across the sciences that centrifuges have been a common piece of laboratory equipment since the late 19th century.