MARY NORRIS, STEPHENVILLE HIGH SCHOOL LIN SHAO, ASSISTANT PROFESSOR NUCLEAR ENGINEERING TEXAS A&M UNIVERSITY The research question: How Does Radiation Affect the Components in a Nuclear Reactor?

Lin Shao Education Ph.D., Physics, University of Houston, 2001 B.S., Nuclear Physics and Technology, Peking (Beijing) University, P. R. China, 1997 Areas of Interest  Materials science and nanotechnology  Radiation effects in nuclear and electronic materials  Ion beam analysis Main Research Group: Nuclear Materials and Fuel Cycles Nuclear Materials and Fuel Cycles

Pressure vessel Pressuerizer Steam generator Pump Containment Pressurized water nuclear reactor

Uranium Enrichment U-238 U235

Fuel Rod and Fuel Assembly

Fission Reaction Stray neutrons cause damage to the metal of surrounding the fuel rods

Damage at the molecular level

Why we care In nuclear reactors, many energetic ions keep bombarding reactor walls. This bombardment can cause bubbles, cracks and voids. This makes the reactor unsafe. We want to know when and how this will happen, but do not want to wait 20 years. Accelerators are used to simulate the environment

Five accelerators ion energy from 10 keV M eV

Ion Beam Analysis view port Ion beam RBS - Rutherford Backscattering for depth profiles of complex thin films (up to a few microns thick and down to a few nm depth resolution). PIXE- Particle (usually proton) Induced X-ray Emission (ppm sensitivities). NRA - Nuclear Reaction Analysis (isotope specific). IBIC - Ion Beam Induced Charge. STIM - Scanning transmission ion microscopy.

Summer Research Particle Ion Irradiation Effects on the Venus Flytrap Leanne Kristek

Gain insights into possible biological effects on living tissue of Venus flytraps Possible reasons for dysfunction:  Trigger hair damage  Ion channels inhibited Identify the critical dose level for noticeable function failure Understand the signal transfer mechanism in Venus flytraps more comprehensively Implications

Venus Fly Trap with trigger hairs

Data Collection Record speed of closure before, after, and possibly during proton and alpha irradiation  Use a high speed camera, e64 Hotshot Mic  Use SCRIM program to determine  Energies to use  Number of damage events for each given energy View structural tomography before and after irradiation to detect ion-solid interaction damage (especially of ion channels, plasmodesmata, and stomata)  Use Scanning Electron Microscope

Question I If the leaf does indeed close once bombarded with the ion beam, are the ion channels of the plant affected? If so, how?  Ion potentials involve Cl −, K +, Ca 2+, and H + If the leaf will not reopen, then how to collect data?  Could try using an electrical current to reopen  Could try irradiating soil instead of directly on leaf

Accelerator Attachment - Faraday Cup - Scintillation Crystal - Sample Holder

Faraday Cup Collects charged particles in a vacuum  Minimal to no backscatter  Placed before the Venus Flytrap Measure the resulting current (I) to determine amount electrons (N) hitting target in time (t):

Scintillation Crystal Ionizing radiation causes luminescence Thus allowing a visual to focus beam

Questions Does the ion beam act on the sensitive filaments or the cells of the leaf itself? Do the trigger hairs and/or cells repair themselves?  Signs of repair

Assel AitkaliyevaGeorge Wei Tianyi Chen Danny Galicki Justin GeneralJosey Wallace McIan Amos Ion & Materials Research Facility (Ion Beam Lab, Accelerator Lab) Lin Shao, Lab Director students M.S. students Undergraduate Alvaro Aranibar Leanne Kristek Lloyd Price Thank You!!! Dr. Shao and his staff have been incredibly welcoming and gracious. They have willingly taken time from their busy schedules to help and answer questions whenever I asked.

Additional Thank You’s TAMU E 3 Program National Science Foundation Nuclear Power Institute Texas Workforce Commission