We have a Glass Expansion cooled spray chamber. At room temperature it yields results similar to the stock PerkinElmer DRC spray chamber. When cooled, the Glass Expansion spray chamber reduces oxides somewhat (20-30%) with little change in signal intensity. Note that coolant temperatures less than -3°C result in ice formation in the spray chamber even with dilute nitric acid solutions. We usually run our spray chamber at -2°C.
This shows that oxides increase dramatically at higher nebulizer flow rates. The general shape of the curve remains the same, though the actual values on the X-axis tend to vary with time, particularly after a power failure knocked out the mass flow controller box. Now the best conditions are typically 0.91 lpm. Also, more typically our CeO+/Ce+ is ~0.02.
This curve is typical of our doubly charged ions. The curve is not as dramaticly sloped as for oxides.