Koehler source

Although this sometimes occurs through the operation of Frank-Read sources it is not generally observed. What does generally occur is similar, but more complex. The process is called multiple-cross-glide, and was proposed by Koehler (1952). Its importance was hrst demonstrated experimentally by Johnston and Gilman (1959). In addition to its existence, they showed that the process produces copious dislocation dipoles which are responsible for deformation-hardening. 

Reymond, J., van Deursen, R., Blum, L.C., and Ruddigkeit, L. (2010) Chemical space as a source for new drugs. Medicinal Chemistry Communications, 1, 30-38. Villar, H.O. and Koehler, R.T. (2000) Comments on the design of chemical libraries for screening. Molecular Diversity, 5, 13-24. 

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