Homepage of David
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Department of
Physics, East Tennessee State University
That's me in the ESR lab, B-24, Brown Hall.
Technical Physics Homework Solutions
Curriculum Vitae: OK, so make me an offer I can't refuse.
Publications: Most recent, and All publications.
Consulting:
- Over the years I have worked on a number of projects
for various companies. One project was to characterize various titanium
dioxide catalysts for the Tennessee Eastman Co. in Kingsport, TN. This
work involved heat treating and evacuating the catalysts, and then
exposing them to gases or organic solvents. The nature of the chemical
reactions that occurred on these surfaces was characterized by ESR. A picture of the chemical
preparation process is shown here.
- I have also done some consulting for the Osteonics Corp. In Allendale, NJ. Osteonics
makes titanium hip joint replacements. To overcome the rejection problem,
these devices are plasma sprayed with bone material (hydroxyapatite). The
coating is then irradiated for sterilization. The high radiation dose
caused the coating to yellow slightly. I used ESR to characterize the
nature of the radiation induced defects in the hydroxyapatite coating.
- I am currently consulting for the Institute for Energy and Environmental Research
in Washington, DC. The Institute seeks to provide the public and policy-
makers with sound scientific and technical studies on a wide range of
issues. I have helped conduct a number of workshops on assessing the risks
of radiation to groups of atomic workers.
That's me, Ellen Kennedy (Staff member of IEER) and Arjun Makhijana (President of IEER).
Honors, Prizes:
- Jürgen Hüttermann (then at Regensburg)
challenged the EPR community to find and characterize the guanine cation.
He promosed a case of his local Kneitinger beer to anyone producing ESR evidence
characterizing the guanine cation. This was around 1982. Bill Nelson
(Georgia State) and I had begun attempts to grow guanine crystals in
strong acid. We succeeded in growing several good size crystals of guanine
hydrochloride monohydrate and of guanine hydrochloride dihydrate
(actually from the same preparation). We began the ESR/ENDOR liquid helium
and liquid nitrogens that summer. Our original
experiments were rather dissappointing.
- At that time I had also begun a collaboration with
Einar Sagstuen (Univ. Of Oslo). We talked about trying to repeat our EPR
experiments, and succeeded in producing the following angular plot of the
ESR data.
This is the X-band ESR angular plot of guanine hydrochloride monohydrate, x-irradiated and observed at 77 K, showing evidence of the guanine cation (the weak outer lines of the spectra).
- When Jürgen saw this spectrum he knew that we had
the guanine cation. He delivered the case of Kneitinger
to me at the Faraday Discussion Meeting in Leicester in 1984.
