A software package operates the spectrometer, acquires the data, and analyzes the spectrum to provide elements and their weight fractions. By measuring the intensity of the peaks, the amount of each element can be determined. By measuring the energy of the X-rays, elements are identified. These characteristic X-rays produce peaks in the Xray spectrum. The spectrometer excites atoms in the regolith and causes them to emit their characteristic X-rays. User’s Manual Overview The X-ray fluorescence spectrometer (XRFS) is designed to be deployed down a predrilled hole for exploration and elemental analysis of subsurface planetary regolith (Figure 2 and Figure 10). 39 Test Plan Summary.41 Results.42 Conclusions.52 Appendices.53 34 Spectrum Processing (SP).36 Spectrum Display (SD).36 Instrument Performance Report. 31 Save and Load Parameters (PAR).33 Save and Load Spectrum (SSF). 40 Hardware Description.23 XRF Interface Unit.23 XRF Control Unit.26 Software Description. 15 Typical Operation.19 Determining the Minimum Detection Limit (MDL). 1 Overview.1 Borehole XRFS Software Installation. The University of Washington effort was funded under NASA contract NNL05AA49C.Ĭontents User’s Manual. The performance reported here is due to their efforts. The XRF spectrometer design and construction were performed by the Ocean Engineering Department of the Applied Physics Laboratory: Russ Light, Vern Miller, Pete Sabin, Fran Olson, Tim Wen, and Dan Stearns. We are indebted to the program managers, Suparna Mukherjee and Chester Chu, for their guidance. APPLIED PHYSICS LABORATORY_Īcknowledgments This project was funded by NASA Headquarters as part of the Mars Technology Program, Subsurface Access Task, administered by the Jet Propulsion Laboratory.CAUTION CAUTION CAUTIONĪpplied Physics Laboratory University of Washington 1013 NE 40th Street Seattle, Washington 98105-6698 This device produces X-rays when energized. Willard-Schmoe2 1NASA Langley Research Center, Hampton, VA 2Applied Physics Laboratory, University of Washington, Seattle The experimental results showed a higher increase of the intracellular Ca 2+ concentration in cells treated with non-organic samples compared to the cells treated with organic samples.Approved for public release distribution is unlimited.īorehole X-Ray Fluorescence Spectrometer (XRFS): User's Manual, Software Description, and Performance Report built by APL-UW under a NASA contract from the Langley Research Center W.C. The tomato samples were either organically grown or contained 14 different pesticides. Finally, for the investigation of the effects of different pesticides on the accumulation of cytosolic Ca 2+, we conducted a fluorescent assay on N2a cells treated with tomato sample extracts, which were replicates of the E.U. The lowest detected concentration was 3 nM. Based on the observed patterns of response, we demonstrate that the sensor can be used for the qualitative and, in some concentrations, quantitative detection of the pesticides with a high degree of reproducibility. In this way, we hoped to increase the selectivity of the assay. Two different cell types, N2a (neuroblastoma) and Vero (fibroblast) were used as the biosensory elements in order to investigate their differential response against the pesticides. The pesticides used were the organophosphate insecticide diazinon and the dithiocarbamate fungicide propineb. The cells were immobilized by entrapment in a sodium alginate bead and directly applied in different pesticide dilutions and agricultural samples. This study presents the construction of a rapid and sensitive cellular biosensor test based on the measurement of changes of the cell membrane potential of immobilized cells, according to the working principle of the Bioelectric Recognition Assay (BERA). Their extensive and inappropriate use has rendered their reliable monitoring at trace levels more and more necessary. Two of the most important categories of pesticides used in agricultural practice are organophosphates and dithiocarbamates.
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