Synchrotron based spectroscopy, Nanoparticles, Speciation of contaminants
Education: Ph.D., Stanford University
Nanoparticles are ubiquitous and widely distributed in natural environments. Dr. Ha's research focuses on the environmental impact of both engineered and naturally occurring nanoparticles by studying their unique properties and sorption reactions with number of different naturally occurring constituents and contaminants. She is also interested in safety and toxicity of nanoparticles once they are released to subsurface aquatic environments. In her work, she applies synchrotron-based tools, such as X-ray absorption spectroscopy (XAS) and scanning transmission X-ray microscopy (STXM), to get chemical identification and speciation at molecular level. Results from her research will elucidate fate and impact of nanoparticles on natural ecosystems and enhance understanding of the chemical and physical properties nanoparticles.
- Ha, J.; Chae, S.; Chou, K. W.; Tyliszczak, T.; Monteiro, P. J. M. C-S-H Effect of polymers on the nanostructure and on the carbonation of calcium silicate hydrates: a scanning transmission X-ray microscopy study. Journal of Material Sciences 2011, DOI: 10.1007/s10853-011-5877-x.
- Ha, J.; Yoon, S.; Monteiro, P. J. M. Cl interaction with green cements: STXM study. Cement and Concrete Research 2011, submitted.
- Ha, J.; Chae, S.; Chou, K. W.; Tyliszczak, T.; Monteiro, P. J. M. Characterization of Fly ash using µ-XRD and STXM. Environmental Science and Technology 2011, submitted.
- Kausch, M.; Ha, J.; Pallud, C. Heterogeneou selenium reduction in artificial soil aggregates. Environmental Science and Technolgoy 2011, in prep.
- Yoon, T.; Ha, J. Brown, G. E., Jr. ATR-FTIR and EXAFS Spectroscopic Study of Interfacial Species in the Pb(II)- Oxalate-Boehmite Ternary System. Journal of Colloid and Interface Sciences 2011, submitted.
- Ha, J.; Gelabert, A.; Spormann, A. M.; Brown, G. E., Jr. Role of extracellular polymeric substances in metal ion complexation on Shewanella oneidensis: Batch uptake, thermodynamic modeling, ATR-FTIR, and EXAFS study. Geochimica et Cosmochimica Acta 2010, 74(1), 1-15.
- Ha, J.; Trainor, T.; Farges, F.; Brown, G. E., Jr. Interaction of Zn(II) with Hematite Nanoparticles and Microparticles: Part 2. ATR-FTIR and EXAFS Study of the Aqueous Zn(II)/Oxalate/Hematite Ternary System. Langmuir 2009, 25 (10), 5586-5593.
- Ha, J.; Trainor, T.; Farges, F.; Brown, G. E., Jr. Interaction of Aqueous Zn(II) with Hematite Nanoparticles and Microparticles. Part 1. EXAFS Study of Zn(II) Adsorption and Precipitation. Langmuir 2009, 25 (10), 5574-5585.
- Yoon, J., Ha, J., Hwang, J., Hwang, B.H., and Brown, G.E. Jr., Study of Iodide Adsorption on Organobentonite using X-ray Absorption Spectroscopy. Journal of the Mineralogical Society of Korea, 2009, 22 (1), 23-34.
- Ha, J.; Yoon, T.; Wang, Y.; Musgrave, C.; Brown, G. E., Jr. Adsorption of Organic Matter at Mineral/Water Interfaces: 7. ATR-FTIR and Quantum Chemical Study of Lactate Interactions with Hematite Nanoparticles. Langmuir 2008, 24 (13), 6683 - 6692.
- Ha, J.; Farges, F.; Brown, G. E., Jr. Adsorption and precipitation of aqueous Zn(II) on hematite nano- and microparticles. AIP Conference Proceedings, 882 (X-Ray Absorption Fine Structure (XAFS13)), 2007, 238-240.
- Ha, J.; Cordova, C. D.; Yoon, T. H.; Spormann, A. M.; Brown, G. E. Microbial reduction of hematite: Effects of particle size and exopolysaccharides Geochimica et Cosmochimica Acta 2006, 70 (18), A