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It's ELEMENTary, our dear Watson!

It's ELEMENTary, our dear Watson!. J. Daniel Bourland, PhD, DABR Associate Professor Dept of Radiation Oncology Wake Forest University Winston-Salem, NC bourland@wfubmc.edu. Nelson W. Couch, PhD, CIH, CSP, Col-ret Triangle Health & Safety, Inc. Durham, NC (Adjunct Professor: UNC & NCSU)

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It's ELEMENTary, our dear Watson!

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  1. It's ELEMENTary, our dear Watson! J. Daniel Bourland, PhD, DABR Associate Professor Dept of Radiation Oncology Wake Forest University Winston-Salem, NC bourland@wfubmc.edu Nelson W. Couch, PhD, CIH, CSP, Col-ret Triangle Health & Safety, Inc. Durham, NC (Adjunct Professor: UNC & NCSU) ncouch8@earthlink.net 919-544-2853

  2. James E. Watson, Jr. • Quiet charisma, soft spoken, Southern Gentleman • “Jim” to his friends and colleagues “Dr. Watson” to his students • Quiet and unassuming, but very organized - he seemed to have a plan • BS and MS: NC State; PhD: UNC • 27 years on UNC faculty; many awards for his teaching, research and service • President national HPS - 1985 to 1986 • Recipient of the North Carolina’s “Order of the Long Leaf Pine”, the highest honor awarded by the state of North Carolina to a citizen

  3. James E. Watson, Jr. • Research: • Radon • Radioactive Waste • Dose Reconstruction • Teacher - Mentor, Coach • Emphasized practical, health protection approach • Always had time and eager to help • Encouraged and enabled achievement • HP & IH program • His students filled careers in industry, government, academia and military , Colleague & Friend

  4. Incineration of Radioactive Waste H-3 C-14 C-14 H-3 H-3 C-14 H-3 Most incinerator licensing criteria held to 10% MPC top of stack

  5. Dry & Wet Adiabatic Lapse Rate Wet Adiabatic~ 6ºC/1000 m 3000 Neutral: D Dry Adiabatic ~1ºC/ 100 m Subadiabtic Stable: E, F 2000 Altitude, meters Inversion Superadiabtic Unstable: A, B, C 1000 0 -15 -10 -5 0 5 10 15 20 25 Temperature ºC Atmospheric Meteorology ° ° °

  6. Visualization of Atmospheric Conditions Stable - Inversion Strong Instability Unstable below, stable above Stable Stable below, unstable above

  7. Visualization of Atmospheric Conditions

  8. …sometimes it gets a little strange!

  9. T H = h + d(v/µ)1.4(1+ ) T (x,y,0) = Q exp[-(y2/2y2 +H2/2z2)]  y z µ Gaussian Plume Dispersion Model Z sz sy X (x,-y,Z) (x,0,0) (x,-y,0) Y H h

  10. N 8 NNW NNE 6 NE NW 4 WNW ENE 2 W E WSW ESE SE SW SSW SSE S Wind Rose (RDU) Average Annual Wind Speeds (m/sec) By Direction

  11. N NNW NNE NE NW WNW ENE W E (2.32) 800 m (1.80) 6-700 m WSW (0.89) 700 m ESE (0.74) 800 m (2.30) 600 m SE SW (1.70) 500 m (0.74) 700 m SSW SSE (1.80) 500 m S (0.92) 700 m (1.20) 600 m (1.20) 600 m (0.89) 500 m (1.10) 600 m (1.20) 800 m (1.40) 6-700 m (2.20) 700 m Maximum Ground Concentrations H-3 (x10-12mCi/ml)

  12. N NNW NNE NE NW WNW ENE W E WSW ESE 2.0 2.0 SE SW 0.75 SSW SSE S 0.2 1.5 0.5 1.0 1.2 1.2 2.0 1.5 Ground Level Concentrations GLC: 105 below top of stack; 103 to 107 below respective MPC Licensing criteria of 10% MPC top of stack too conservative H-3 MSPH: 1981 Won NC and HPS Std Awards (x10-12mCi/ml)

  13. Beta Dosimetry Holding vial for 5 minutes Energetic Beta Finger/hand dose from uranium beta

  14. TLD Thickness TLD chip - 0.13 mm LiF-Teflon TLD - 0.5 mm LiF-Teflon TLD - 0.78 mm LiF chip - 0.9 mm LiF chip

  15. Gremlin in the Works Beta Dosimetry Teledyne Isotopes TLD Reader Model 7300 Donated by Duke Power Panasonic TLD’s: LiF in Telfon 1 cm diameter 0.13 mm thick Very Thin Supported by NIEHS

  16. Extrapolation Chamber 3 cm dia active volume with 2.6 mg/cm2 window Standard Beta Sources NTIS traceable: Sr/Y-90; Tl-204, Tc-99 NEIHS prepared: Sr/Y-90; Tl-204, Tc-99, P-32 Electrometer capable of measuring 10-13 A

  17. Extrapolation Chamber Ionization Current (10-13 A) Chamber Depth (cm)

  18. Extrapolation Chamber Ionization Current (10-13 A) Chamber Depth (cm)

  19. Extrapolation Chamber Ionization Current (10-13 A) dx di Slope = di/dx Dtis (mrad/h) = S(1.9x1012)/r Chamber Depth (cm) Note: 45 to 60 minutes per measurement

  20. Log Dose Depth Beta Fingertip Dosimeter ID Beta Thin flexible backing – like a “band-aid” Up to 4 LiF-Teflon TLD’s Thin cover to protect TLD’s MDD: 40 mrem – low E 18 mrem – high E

  21. Beta Fingertip Dosimeter • Range: • 0.127 to 1.93 Rem/mo • Peaks: • 3.4 Rem in 1 day • 1.3 to 1.6 Rem in 9 to 14 days • Average: • 0.416 ± 0.486 rem/mo 40 mCi P-32 in an Eppendorf Tube measured 300 mRem/min 2 other std’s earned MSPH’s NIEHS used until 3 yrs ago PhD: 1986

  22. Educational Life with Jim Watson“He was the Radiological Hygiene Program” Assistant Professor, Program Director1977 Peterson’s Guides

  23. Educational Life with Jim WatsonStudents Always First – Facilitated Education

  24. Educational Life with Jim WatsonSimplicity of Content, Demand for Excellence Grading Scale H 95 – 100 P+ 90 < 95 P 75 < 90 P- 70 < 75 L 60 < 70 F < 60 Very difficult to get an Honors, and yet with a personal touch.

  25. Educational Life with Jim WatsonThe North Carolina State University Connection How did this ever work? • NC 54 – “swamp run” • Needed courses • Radiation Biology • Nuclear Engineering • Why? Respected former teachers • Drs. AW Waltner and DS Grosch • Why? Dr Watson made the Program work

  26. Evaluation of a Water Immersible Ionization Chamber (MSPH) Duke Univ TZ Wong, F Bagne, PhD

  27. Bragg-Gray Cavity TheoryA Dual-Volume Parallel Plate Chamber

  28. Irradiation GeometryWhere is the measurement point for a parallel plate chamber?

  29. Results: Satisfactory CharacteristicsDeformation of Active Volume Probable NC HPS Student Presentation; Oral Presentation, 1980 AAPM

  30. A Finite-Size Pencil Beam Model for Three-Dimensional Photon Dose Calculations (PhD)

  31. Dr. James E. Watson, Jr.Impact on students and their careers • Always start with first principles • “True scholar and a gentleman” • Simplicity of content, demand for excellence • Students always first • “10% of the nation’s health physicists” • “He was the Radiological Hygiene Program” “He was in the top three of the best teachers I have ever had….he was a true scholar and a gentleman.” (Don Tyndall, DDS, PhD, Professor - UNC Diagnostic Sciences and General Dentistry)

  32. Any Questions?

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