Carbon K-edge NEXAFS spectroscopy

Knowledge graph centered on Carbon K-edge NEXAFS spectroscopy with 68 nodes and 140 connections. Top connected: Bacteria, Organic matter decomposition, Temperature, Dissolved solids concentration, Soil characteristics.

Method synopsis

Near-edge X-ray absorption fine structure spectroscopy analysis at the carbon K-edge using synchrotron radiation to determine functional group composition of organic carbon in sediment samples.

Synthesized from method descriptions across 2 papers using this protocol.

Procedure from a recent peer-reviewed implementation

Steps below were extracted from the most recent peer-reviewed implementation of this protocol in the corpus — Shale as a Source of Organic Carbon in Floodplain Sediments of a Mountainous Watershed (2020), JGR Biogeosciences. Implementations in other papers (listed below) may differ.

1. NEXAFS spectroscopy analysis
   Individual samples were gently ground by hand to break up large aggregates, slurried in deionized water, and pipetted onto In foils. After drying, C NEXAFS spectra were obtained using the spherical grating monochromator beamline 11ID-1 at the Canadian Light Source. Step scan mode (0.25-eV steps from 270 to 320 eV) was used to minimize X-ray damage. A dwell time of 20 ms was used between scans. Individual spectra were collected at new locations on each sample for a total of 40 to 60 scans. The beamline exit slit was set at 25 mm, and the fluorescence yield data were collected using a two-stage microchannel plate detector.
   Quantities: 0.25-eV steps, 270-320 eV energy range, 20 ms dwell time, 40-60 scans per sample, 25 mm beamline exit slitDuration: 20 ms per scan, 40-60 scans totalConditions: Deionized water slurries, air-dried on In foils
   Equipment: spherical grating monochromator beamline 11ID-1, Canadian Light Source, two-stage microchannel plate detector, In foils

Typical Equipment

• spherical grating monochromator beamline 11ID-1
• Canadian Light Source
• two-stage microchannel plate detector
• In foils

Output Measurements

• relative abundance of carbon functional groups
• degree of aromaticity
• oxidation state

Papers Using This Protocol (2)

Species Studied With This Protocol

Places Where Used