THE AFFECTS OF LOW DOSE RADIATION ON POLYMERS Cindy Johnson Palacios High School Mentor John Ford Nuclear Engineering Problem: How does low doses of radiation affect polymers?
Core Elements of Research Properties of polymers Structure Sensitivity to radiation Properties and sources of radiation (TEKS 2,11B&C, 6B) Charge Mass Energy Energy involved with radiation (TEKS 9A) Units - rad/kGy; rem/mrems Purpose: To determine which polymer is the most sensitive to radiation
Safety Guidelines Storage of radioactive materials Do not eat radioactive sources Do not remove the radioactive source from the lab Caution: Sodium Hydroxide is caustic (can cause burns). Wear goggles and aprons
TEKS and TAKS The student is expected to: (2A)TEKS plan and implement investigative procedures including asking questions, formulating testable hypotheses, and selecting equipment and technology; (B) (2B) collect data and make measurements with precision; (B) (2C) express and manipulate chemical quantities (B) (2D) organize, analyze, evaluate, make inferences, and predict trends from data; and (B) (2E) communicate valid conclusions. (B) B represents both TEKS and TAKS
TEKS and TAKS CONT. (6B) analyze stable and unstable isotopes of an element to determine the relationship between the isotope's stability and its application; (11B) demonstrate the use of symbols, formulas, and equations in describing interactions of matter such as nuclear reactions; and (11C) explain and balance nuclear equations using number of atoms, masses, and charge
Lesson Introduction Pretest over radiation Radiation vocabulary Three types of radiation and properties Examine materials for radiation using the Geiger counter Polymers and properties Introduce the experimental procedure
Protocol/Procedure Source of radiation, Americium-241, Coleman Mantles-old Polymers used Preparation Radiation emitted by source Expose the polymers Etch in a 6.5N NaOH Wash and dry Examine and count
Penetrations in CR-39 Using a Mantle Source
Heavy Field of Penetrations Using CR-39 and Am-241
Field Edge Using CR-39 and Am- 241
Comets and Penetrations Using CR-39 and Am-241
Penetrations in Lexan (polycarbonate) Using Am-241
Penetrations and Comets in Lexan Using CR-39 and Am-241
Acetate Using Am-241
Student Analysis Estimate penetrations Rank (sensitivity), determine (best) Cost effective detector. Play CDs or memory cards (susceptible to LDR) Best media storage
Pre-test and Post-test Pre-test Post-test The test will cover questions over the types of radiation and properties, what blocks the particles, vocabulary, energy, polymers
Acknowledgements National Science Foundation for funding E3 RET for a once in a lifetime experience and education Texas A & M University for use of the facilities, the teachers, and the education Dr. John Ford for all of his time, effort, patience, knowledge, and the experience of a lifetime STP for its funding