The Promise and Problems of Nuclear Energy IIChapter 6 Summary AgainReview of FissionEnrichmentSlide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Emissions FreeEarly knowledge of risksStates with nuclear power plant(s)Nuclear power around the globeCountries Generating Most Nuclear PowerSlide 30Slide 31Nuclear Fuel CycleiClicker QuestionSlide 34Slide 35Slide 36Front end: Uranium mining and millingUranium tailings and radon gasRadioactivity BasicsSlide 40Slide 41Slide 42Slide 43Slide 44Slide 45Slide 46Slide 47ALARAALARA PrinciplesSlide 50Background RadiationMetric ConversionsMaximum Permissible Dose Equivalents for Radiation WorkersOccupational ExposureLong-term Effects of Radiation ExposureBioeffects on Surface tissuesUranium EnrichmentRadioactivity of PlutoniumRisks of Enrichment and Fuel FabricationNuclear Fission ReactorsNuclear Plant LayoutThe Core of the ReactorFuel PackagingControl Rod ActionCalifornia Nuclear Plant at San OnofreThe relative cost of nuclear powerSidebar Regarding Nuclear BombsSlide 68Useful Radiation Effects I Nuclear Power Nuclear fission for electricity Thermoelectric for spacecraft Medical: Diagnostic scans, tracers Cancer radiation treatment Plutonium powered pacemaker Medical, dental sterilizationUseful Radiation Effects II Polymer cross-linking Shrink tubing (e.g., turkey wrapping) Ultra-strong materials (e.g., Kevlar) Tires (replaces vulcanization) Flooring Food irradiation Sterilization of meat De-infestation of grain and spices Increase shelf life (e.g., fruits, veggies)Slide 71Slide 72The finite uranium resourceBreeder ReactorsSlide 75Breeders, continuedReactor RisksRisk AssessmentClose to home: Three Mile IslandThe Three-Mile Island Accident, 1979Slide 81Health around TMIPlants near TMIAnimals Nearby TMIThe Chernobyl DisasterChernobyl, continuedChernobyl after-effectsSlide 88Slide 89Radiation and Health“It Can’t Happen Here”Slide 92Slide 93Nuclear ProliferationSlide 95Nuclear WasteStorage SolutionsBurial IssuesYucca MountainTransportation risksTransport to Yucca MountainKyshtym waste disaster, 1957Slide 103Risk of terrorism (new challenge to industry)Slide 105Slide 106Fusion: The big nuclear hopeThermonuclear Fusion in the SunE=mc2 balance sheetsArtificial FusionSlide 111Deuterium everywhereTritium NowhereBy-products?Why don’t we embrace fusion?Fusion Successes?Other Forms of Nuclear Power?Passive Radioactive DecaySlide 119The Seebeck EffectHistory of Peltier devicesPeltier Effect With Dissimilar MetalsSidebar: Semiconductor PeltierSample Peltier Temperature GradientApplicationsRTG Pros and ConsSlide 127Slide 1281The Promise and Problems of Nuclear Energy IILecture #13HNRS 228Energy and the Environment2Chapter 6 Summary Again•History of Nuclear Energy•Radioactivity•Nuclear Reactors•Boiling Water Reactor•Fuel Cycle•Uranium Resources•Environmental and Safety Aspects of Nuclear Energy•Chernobyl Disaster•Nuclear Weapons•Storage of High-Level Radioactive Waste•Cost of Nuclear Power•Nuclear Fusion as a Energy Source•Controlled Thermonuclear Reactions•A Fusion Reactor3Review of Fission•235U will undergo spontaneous fission if a neutron happens by, resulting in:–two sizable nuclear fragments flying out–a few extra neutrons–gamma rays from excited states of daughter nuclei–energetic electrons from beta-decay of daughters•The net result: lots of banging around–generates heat locally (kinetic energy of tiny particles)–for every gram of 235U, get 65 billion Joules, or about 16 million Calories–compare to gasoline at roughly 10 Calories per grama tank of gas could be replaced by a 1-mm pellet of 235U!!4Enrichment•Natural uranium is 99.27% 238U, and only 0.72% 235U–238U is not fissile, and absorbs wandering neutrons•In order for nuclear reaction to self-sustain, must enrich fraction of 235U to 3–5%–interestingly, it was so 3 billion years ago–now probability of wandering neutron hitting 235U is sufficiently high to keep reaction crawling forward•Enrichment is hard to do: a huge technical roadblock to nuclear ambitions5iClicker Question•Which is closest to the half-life of a neutron?–A 5 minutes–B 10 minutes–C 15 minutes–D 20 minutes–E 30 minutes6iClicker Question•Which is closest to the half-life of a neutron?–A 5 minutes–B 10 minutes–C 15 minutes–D 20 minutes–E 30 minutes7iClicker Question•What is the force that keeps the nucleus together?–A weak force–B strong force–C electromagnetic force–D gravitational force8iClicker Question•What is the force that keeps the nucleus together?–A weak force–B strong force–C electromagnetic force–D gravitational force9iClicker Question•A neutron decays. It has no electric charge. If a proton (positively charged) is left behind, what other particle must come out if the net charge is conserved?–A No other particles are needed.–B A negatively charged particle must emerge as well.–C A positively charged particle must emerge as well.–D Another charge will come out, but it could be either positively charged or negatively charged.–E Neutrons cannot exist individually.10iClicker Question•A neutron decays. It has no electric charge. If a proton (positively charged) is left behind, what other particle must come out if the net charge is conserved?–A No other particles are needed.–B A negatively charged particle must emerge as well.–C A positively charged particle must emerge as well.–D Another charge will come out, but it could be either positively charged or negatively charged.–E Neutrons cannot exist individually.11iClicker Question•How many neutrons in U-235?–A 141–B 142–C 143–D 144–E 145U2359212iClicker Question•How many neutrons in U-235?–A 141–B 142–C 143–D 144–E 145U2359213iClicker Question•How many neutrons in Pu-239?–A 141–B 142–C 143–D 144–E 145Pu2399414iClicker Question•How many neutrons in Pu-239?–A 141–B 142–C 143–D 144–E 145Pu2399415iClicker Question•If a substance has a half-life of 30 years, how much will be left after 90 years?–A one-half–B one-third–C one-fourth–D one-sixth–E one-eighth16iClicker Question•If a substance has a half-life of 30 years, how much will be left after 90 years?–A one-half–B one-third–C one-fourth–D one-sixth–E one-eighth17iClicker Question•If one of the neutrons in