The objectives in this research program are to develop new methods for the quantitative determination and for the speciation of trace (ppm to ppb) elements in complex solid or liquid matrices. Elemental profiles in environmental and biological samples have been obtained by X-ray fluorescence (XRF) and at trace levels, by proton induced X-ray emission (PIXE). This analytical capability will be developed further with special attention being devoted to improving techniques of sample preparation. This multielemental technique will be used for the speciation of heavy elements. This will be accomplished by carrying out preconcentration and chemical separations of the various species, for example, the four arsenic species commonly encountered in biological samples, and employing the PIXE technique for determining the elemental concentration. Alternative methods based on the kinetic control of chemical reactions will be explored for the speciation of elements such as arsenic. The most important objective in this research program is to extend the PIXE capability to include the use of a proton microprobe (micro-PIXE) for the measurement of elemental concentrations in microscopic size samples. Elemental profiles will be determined in a target area 100 mum x 100 mum, by rastering a 1 mum x 1 mum proton beam across this target area. Precautions will be taken to minimize sample degradation by the effects of heat and radiation damage. Elemental maps of tissue slices and single cells will be obtained with this micro-PIXE system.

Project Start
Project End
Budget Start
Budget End
Support Year
4
Fiscal Year
1993
Total Cost
Indirect Cost
Name
University of Arizona
Department
Type
DUNS #
City
Tucson
State
AZ
Country
United States
Zip Code
85721
Pu, Mengjie; Guan, Zeyu; Ma, Yongwen et al. (2018) Synthesis of iron-based metal-organic framework MIL-53 as an efficient catalyst to activate persulfate for the degradation of Orange G in aqueous solution. Appl Catal A Gen 549:82-92
Brusseau, Mark L; Guo, Zhilin (2018) The integrated contaminant elution and tracer test toolkit, ICET3, for improved characterization of mass transfer, attenuation, and mass removal. J Contam Hydrol 208:17-26
Valentín-Vargas, Alexis; Neilson, Julia W; Root, Robert A et al. (2018) Treatment impacts on temporal microbial community dynamics during phytostabilization of acid-generating mine tailings in semiarid regions. Sci Total Environ 618:357-368
Brusseau, Mark L (2018) Assessing the potential contributions of additional retention processes to PFAS retardation in the subsurface. Sci Total Environ 613-614:176-185
Delikhoon, Mahdieh; Fazlzadeh, Mehdi; Sorooshian, Armin et al. (2018) Characteristics and health effects of formaldehyde and acetaldehyde in an urban area in Iran. Environ Pollut 242:938-951
Hammond, Corin M; Root, Robert A; Maier, Raina M et al. (2018) Mechanisms of Arsenic Sequestration by Prosopis juliflora during the Phytostabilization of Metalliferous Mine Tailings. Environ Sci Technol 52:1156-1164
Yan, Ni; Zhong, Hua; Brusseau, Mark L (2018) The natural activation ability of subsurface media to promote in-situ chemical oxidation of 1,4-dioxane. Water Res 149:386-393
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Liu, Pengfei; Rojo de la Vega, Montserrat; Sammani, Saad et al. (2018) RPA1 binding to NRF2 switches ARE-dependent transcriptional activation to ARE-NRE-dependent repression. Proc Natl Acad Sci U S A 115:E10352-E10361
Thomas, Andrew N; Root, Robert A; Lantz, R Clark et al. (2018) Oxidative weathering decreases bioaccessibility of toxic metal(loid)s in PM10 emissions from sulfide mine tailings. Geohealth 2:118-138

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