Carbocations are species bearing a formal + charge on carbon. The have sp2 hybridization and trigonal planar geometry, with an empty p orbital on carbon, perpendicular to the plane containing the substituents (see diagrams shown to the right).
Aortic cross-clamp. An aortic cross-clamp is a surgical instrument used in cardiac surgery to clamp the aorta and separate the systemic circulation from the outflow of the heart. An aortic cross-clamping procedure serves, for example, in the repairing of coarctation of the aorta.
Salter Labs - 1005-0-1. Tender Grips are a unique skin fixation system designed to hold nasal cannulas and oxygen tubing in place on the face. Tender Grips are easy to apply, allow the skin to breathe, hold securely and don't leave any messy residue when removed.