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A Synchrotron radiation student project in our community college consists of data collection, data analysis, and discussion which includes the formulation of a new hypothesis. Although the on-site data collection at National Labs such as NSLS II at BNL, Cornell High Energy Synchrotron Source are limited by the Synchrotron beam time availability students were able to participate on site data analysis from previously collected data. The data analysis component fully engages the students in Extended X ray Absorption Fine Structure(EXAFS), X ray absorption Near Edge Structure (XANES), and X ray absorption pre edge feature analysis. These tools were used to analyze microstructure of iron and zinc compounds in a variety of samples. In EXAFS experiments data consists of absorption coefficient of element under investigation versus X ray energy at the vicinity of an absorption edge and about 200 eV below & 1000 eV above the edge energy. Analysis of EXFS data yields the amount of the element under investigation and structural parameters such as oxidation state, near neighbor bond length, number of near neighbor atoms and disorder. The advantage of this method is minimal sample preparation and no chemical treatments to samples. The pedagogy encourages mindful reading of the latest Synchrotron based research articles with faculty guidance to build a relationship to a chemical engineering related education. The pedagogy of using the Synchrotron radiation student projects in community college has been found to broaden the prospect and build connections to chemical engineering related education in the senior college setting. The data analysis steps of several different material and structure interpretations will be presented.
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This content will become publicly available on March 1, 2026
Study of microstructure of iron species in plants using X ray absorption spectroscopy
The X-ray absorption spectroscopy including Extended X ray Absorption Fine Structure (EXAFS) , X ray Absorption Near Edge Structure (XANES) and X-ray absorption near edge and pre edge feature is used to analyze the nature and concentration of iron in plants, spinach and parsley. Primary data was collected at Cornell High Energy Synchrotron Source. Data analyses were done by community college students. EXAFS data analysis process include edge normalization, background subtraction, transformation to k space from energy, Fourier transformation, back transform of selected peaks, and curve fitting to identify type and number of near neighbor atoms. X-ray absorption pre=edge feature, which appears as very small absorption peak before the main peak, is used to study ironoxygen bonding and asymmetry of iron compounds. Pre edge data analysis include extraction of the pre-edge from main absorption spectrum, normalization to main edge height, and Lorentzian fit to back ground subtracted data. X-ray absorption data from spinach and parsley, as well as several iron supplements and the soil of which plants were grown was analyzed. The preliminary data analysis pre edge feature yields two forms of iron in both plants. One form has oxygen as near neighbor atoms and the other without oxygen.
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- Award ID(s):
- 2150404
- PAR ID:
- 10593168
- Publisher / Repository:
- ASEE Conferences
- Date Published:
- Format(s):
- Medium: X
- Location:
- University of Bridgeport, Bridgeport, CT
- Sponsoring Org:
- National Science Foundation
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