This Ocean Sciences Instrumentation Development project will continue development of a submersible chemical analyzer (Scanner) that can be widely used for oceanographic studies. The new instrument will be suitable for deployment on profiling instruments or research submersibles, as well as on platforms such as benthic flux chambers and deep towed vehicles, and on moorings for longer term (up to four-month) deployments. The proposed design is simple and flexible, which will allow it to be used for both macro-nutrients, as well as trace elements. This new generation of the existing Scanner requires a new pumping system and other refinements. Micro-solenoid pumps will be used that are smaller and lighter than previous peristaltic pumps and they can be individually controlled. The flexibility of individual microprocessor control of each flow stream allows variable flow rates (including no flow) for each reagent, sample and standard. This will facilitate assay optimization and make it possible to access several different analyses on the same Scanner system. The goal of this fourth generation scanner is a substantially simpler and more robust system than previous versions that can be used in a greater variety of studies. There is a clear need for improved instruments capable of performing chemical measurements in situ. The science plans for many large scale research projects call for this capability.
