色谱产品原理应用维护基础知识讲座.ppt

PerkinElmer Instructor Notes Day1 Part 1 * In this picture we see the additional plumbing associated with the online sampling accessory and additional components for the ozone precursor system highlighted in gray. Two additional rotary valves are included with the accessory - these are both mounted within the ‘box’ fitted to the rear of the TD. RVB directs the sample stream either directly to a flow controller and vacuum pump or through the (empty) tube and the trap. Control of the flow controller is integrated within the TurboMatrix TD and there is no need for an external control box (as was needed with the ATD400). ISV1 is normally left open during system operation but will close in the event of a power interruption and so prevent possible loss of expensive calibrant gas under such circumstances. RVC is used to select between two gas streams - sample or calibrant. A Nafion drier is used for water removal from the sample stream - full pneumatic control for the drier is provided. Note that the plumbing around the main valve, RVA, is not changed and so tube sampling is still supported with no modifications. A fuller explanation of the operation of this accessory is given later in this presentation. This accessory may be fitted to either an ATD or TD but as the ozone precursor analysis requires a cooled adsorbent to retain the C2 analytes, tube sampling is not possible and so the ozone precursor system is only configured using a TD. PerkinElmer Instructor Notes Day1 Part 1 * This slide shows the key components of the heartcut system. There are essentially three components - A second pressure regulator (P2) - A 3-way solenoid valve - A purpose designed T-piece Two columns are used - A methyl silicone column for the heavier sample fraction, connected between the thermal desorption system and the T-piece - An alumina porous layer open tubular (PLOT) column for the lighter sample fraction connected between one arm of the T-piece and one of the detectors A fused s