Couplage croiséEn chimie organique, un couplage croisé est une réaction de couplage entre deux fragments moléculaires par formation d'une liaison carbone-carbone sous l'effet d'un catalyseur organométallique. Par exemple, un composé , où R est un fragment organique et M un métal du groupe principal, réagit avec un halogénure organique , où X est un halogène, pour former un produit . Les chimistes Richard Heck, Ei-ichi Negishi et Akira Suzuki ont reçu le prix Nobel de chimie 2010 pour avoir développé des réactions de couplage catalysées au palladium.
Split-phase electric powerA split-phase or single-phase three-wire system is a type of single-phase electric power distribution. It is the alternating current (AC) equivalent of the original Edison Machine Works three-wire direct-current system. Its primary advantage is that, for a given capacity of a distribution system, it saves conductor material over a single-ended single-phase system, while only requiring a single phase on the supply side of the distribution transformer. This system is common in North America for residential and light commercial applications.
Cray-1The Cray-1 was a supercomputer designed, manufactured and marketed by Cray Research. Announced in 1975, the first Cray-1 system was installed at Los Alamos National Laboratory in 1976. Eventually, eighty Cray-1s were sold, making it one of the most successful supercomputers in history. It is perhaps best known for its unique shape, a relatively small C-shaped cabinet with a ring of benches around the outside covering the power supplies and the cooling system. The Cray-1 was the first supercomputer to successfully implement the vector processor design.
