Milpitas, California disk subsystem integrator System Industries Inc has completed acquisition of the assets of the Imperial Technology subsidiary of First Mississippi Corp for $11.5m cash, 500,000 new shares worth about $3.2m, and further payments based on future performance. Imperial does about $10m a year in high performance solid state disk emulators, the majority of its MegaRAM and MegaCARD systems going to DEC users needing high levels of performance and throughput in telecommunications, scientific research, real time databases and computer generated graphics.