New Zealand-based infrastructure company Infratil and Australian investment firm Morrison are to buy a majority stake in Qscan Radiology Clinics, the Queensland-focused, radiologist owned and operated diagnostic medical imaging provider, from Quadrant Private Equity. The consortium could pay as much as A$735m (US$525.5m). Sydney-based Quadrant paid A$110m for its 55% stake in May 2017, though…