Research On Mass Spectrometer Based Instrument For Express Measurement Of Oceanic Pollution

The exploitation and utilization of modern ocean resources has brought huge economic benefits, in the meanwhile, also brought series problems of resources and ecological environments. The research and development of Ocean Monitoring Technology, which will provide scientific data and base for marine ecological calamity forecast, prevention and control technology, becomes more and more important. At present, the measurements of ecological environment parameters including organic pollutants, nutrient salts, heavy metals etc. are gained from on-site sampling and chemical analysis inside the lab afterwards. Facing the complexity and urgency of the current status of oceanic pollution, it is quite necessary to develop a comprehensive measuring instrument which can take measurement of all kinds of pollutants in the oceanic environment simply and rapidly.There are several kinds of techniques for on-line oceanic pollutants measuring, each has its advantages and disadvantages. Among them, the instrument based on mass spectrometric technique has more advantages from the aspects of measurement kind, accuracy, speed and practicability. Mass Spectrometer is a kind of instrument based on the theory that when being forced, the charged particles can deflect in the electromagnetic field, which is able to do separation according to the mass difference among atom, molecule or molecular fractionation and detection of material composition.The aim of this research is to design an automation equipment used on coastal observation station, offshore platform, buoy, ship to perform real-time and on-line measurement of oceanic pollution. Based on mass spectrum theory, this instrument can perform qualitative and quantitative measurement of various pollutants.The instrument for express measurement of oceanic pollution is based on the theory of mass spectrum, it uses separate structure design. The system consists of two parts, front-end acquisition unit and operating terminal. The front-end acquisition unit has the function of sample, measure, qualitative and quantitative analysis of pollutants, data storage, data transmission etc. The operating terminal has the function of displaying of real time measurement result and working state, calibration and working parameters setup, storage and query of historical data, affording other sensor interface etc. The system consists of vacuum system, sampling system, ion source, mass analyzer, detectors, other mechanical and electrical parts. The front-end acquisition unit uses TMS320F2812 DSP controller as core controller. The operating terminal's core controller is AVR MCU ATxmega128A1. This paper introduces the composition of system and focuses on the design of control circuit.We carry calibration and experimental verification on this system, the experiment results indicate that this instrument can meet the requirement of the various marine pollutant's measurement.