英语翻译In a preceding section on the forward characteristics of

英语翻译
In a preceding section on the forward characteristics of a pn junction diode,we have implicitly assumed that there is no carrier generation and recombination within the space-charge region.However,the bias changes the carrier concentration at the edges of the space-charge layer,so that pn!=n^2.Carrier generation and recombination do occur in the transition region and also contribute to current.
pn!=n^2 专业术语 可不翻译！