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D4222-1headline bar  Two scientists using a mass spectrometer and looking at data on a screen**Image Number D4222-1** Research chemists Cathleen Hapeman (HRSL) and Clifford Rice (SASL) use a liquid chromatograph tandem quadrupole mass spectrometer (LC-MS/MS) to study water samples from the POCIS. The data obtained will be coupled with landscape and other stream data to consider the source of nutrients in the streams.  Photo by Peggy Greb. 640 pixels wide: (D4222-1.jpg)   Please visit our Image Gallery.


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