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Nuclear Energy and Radiation!
• November 3, 2007
• Larry R. Foulke
• Director of Nuclear Programs, University of Pittsburgh
Presentation to the Westinghouse Science Honors Institute
ATOM• ELECTRONS
• NUCLEUS– Proton
– Neutron
“The Planatary Atom”
ATOM• ELECTRONS
• NUCLEUS– Proton
– Neutron
• CHARACTERIZATION– Atomic Number Z = #e = #p
– Atomic Mass Number A = #p + #n
NUCLEUS
• NUCLIDE -- A specific nucleus configuration (#p & #n)
XAZ
...XXX 2AZ
1AZ
AZ
++
• ISOTOPE -- Different nucleus configurations (# n) of the same chemical element (#p)
ISOTOPES
238UraniumU237UraniumU
236UraniumU235UraniumU
234UraniumU233UraniumU
232UraniumU
23892
23792
23692
23592
23492
23392
23292
−
−
−
−
−
−
−
ISOTOPES
TritiumTorHDeuteriumDorH
HydrogenH
31
31
21
21
11
NUCLEUS
• NUCLEAR FORCES– Overcome Proton Repulsion
• Strong
• Short Range
• MASS DEFECT
MAtom < Σ MConstituents
• MASS DEFECT
MAtom < Σ MConstituents
• MASS-ENERGY EQUIVALENCEE = mc2
• BINDING ENERGY
BE = [ MAtom - Σ MConstituents ]c2
NUCLEAR FORCES
Binding Energy/Nucleon
ΔBE
235U FissionΔBE/nucleon x 236
~ 200 MeV
Binding Energy/Nucleon
FissionProducts
MASS AND ENERGY SCALES• Atomic Mass Unit
1 amu = 1/12 mass of Carbon-12 atom = 1.660565 x 10−27 kg
• Electron Volt1 eV = 1 electron charge x 1 volt
= 1.60219 x 10− 19 Joules (watt-secs)1 keV = 1,000 eV1 MeV = 1,000,000 eV
• E=mc2
1 amu = 931.5016 MeV
Δ BE
D-T Fusion
Binding Energy/Nucleon
RADIOACTIVE DECAY
• EXCESS ENERGY IN NUCLEUS• CONSERVATION LAWS
– Charge– Mass Number– Total Energy– Momentum
• PROBABILITY
γ+→
γ•
ν+β+→
ν+β+→
=ν=β•
α+→
=α•
∗
−
−
−−
++
++++
00
23692
23692
00
00
01
11
10
00
01
9039
9038
01
01
42
23190
23592
42
42
UUGAMMA
*pn
*YSrneutrino*eBETA
ThUHeALPHA
anti
NATURAL RADIOACTIVITY
Radioactivity
Penetrating Properties of Ionizing Radiation
Radioactive Half-Life
HALF-LIFE EXAMPLES
• URANIUM 232 70 yr233 160 000 yr234 250 000 yr235 700 000 000 yr236 23 000 000 yr238 4 500 000 000 yr
• FISSION PRODUCTSStrontium-90 29 yrCesium-137 30 yr
NUCLEAR REACTIONS• PROJECTILE / TARGET• COMPOUND NUCLEUS C*• PRODUCTS
Nuclear Reaction
NUCLEAR REACTIONS• PROJECTILE / TARGET• COMPOUND NUCLEUS C*• PRODUCTS
X + x → C* → Y + yX(x,y)YX(x,y)
• “ARTIFICIAL”/“MAN-MADE”– Radioactivity– Energy– Conservation Laws
REACTION ENERGY BALANCEEX + MXc2 + Ex + Mxc2 = EY + MYc2 + Ey + Myc2
Ei Kinetic Energy of Constituent iMic2 Mass Energy of Constituent i
[(EY + Ey ) − (EX + Ex)] = Q-Value
[(EY + Ey ) − (EX + Ex)] = [(MX + Mx) − (MY + My)]c2
Q > 0 → Exothermal [Exoergic] Reaction
Q < 0 → Endothermal [Endoergic] Reaction|Q| = Threshold Energy
Nuclear Fission
NUCLEAR FISSION
• ADVANTAGES– Energy Output
Coal 235U2500 tons 1 lb5000 tonnes 1 kg
• Combustion (C+O2 → CO2 ) 2-3 eV• Fission 200,000,000 eV
[200 MeV]
Nuclear Fission
NUCLEAR FISSION• ADVANTAGES
– Energy Output– Neutrons
• DISADVANTAGES– Fission Radiation Shielding/Heat RemovalShielding/Heat Removal– Fission-Product Radiation
Shielding/Containment/HeatShielding/Containment/Heat RemovalRemoval
Waste Management & DisposalWaste Management & Disposal
Pressurized Water Reactor (PWR)
QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture.
PWR Steam Cycle
Uranium Fuel Pellets (one pellet equals 2,000 lbs of coal)
1999 U.S. Electrical Energy By Source(Ref: Annual Energy Outlook 2001, DOE/EIA-0383, 2001)
~10% (wind and solar = 0.15%)
Renewables
20%Nuclear
16%Natural Gas
3%Petroleum
51%Coal
Percent of TotalSource
• 440 nuclear power plants
• 16% of world’s electricity
• Displaces 2.5 billion metric tons of CO2/year
World View
• World nuclear generation sets record in 2004– 383,629 MW– 2,696 MMWh (3.7% increase)
• Led by:– Record setting performance
• U.S.• Sweden
– Restart of units in:• Japan• Canada
– Commissioning of new units• South Korea• Ukraine
World View
Substantial New GW Targets
24 by 202043India
10 additional by 2015
15-25 additional by 2020
15 on order or planned by 2015
36 by 2020
Target(GW)
8.816South Korea
1.922Russia
3.245Japan
2.07China
UnderConstruction
(GW)
Operating(GW)Country
• Quick facts
– 103 nuclear plants– 20% of the nation’s electricity
U.S. Nuclear Energy
– Displaces 680 million metric tons of CO2/yr
– Equivalent to 131 millionpassenger cars/yr
U.S. Nuclear Drivers
• Safe• Proven performance• Cost effective• Affordable• Energy security/
energy independence• Base load generation/
grid stability• Emission-free
85 87 89 91 93 95 97 99 01 03
0
1
2
3
4
5
6
7
8
9
10
11
Source: Federal Energy Regulatory Commission /EUCG
Nuclear 1.72Coal 1.8Gas 5.77Oil 5.53
United StatesCost Effective (in constant cents/kWh)
U.S. Energy DemandAmerica Is Projected to Need 50% More Electricity by 2025
Source: U.S. Department of Energy
1980 19901970 2003 2015 2025
5,787BkWh
3,839BkWh
Nuclear Science and Technology is Much More Than Nuclear Power !!
Nuclear Science and Technology• Medicine• Agriculture• Industry• Environmental Protection• Public Safety and Basic Science• Space Exploration
Ubiquity of Radiation Applications
Overall impact in the U.S.(1995 data, based on multiplicative effects)
SALES
Radioisotopes
JOBS
Nuclear Energy
331$ Billions
4.0
90 0.4
421* 4.4*Larger than General Motors*Larger than entire U.S. Airline industry
Millions
Ref: www.nei.org
Medicine
• Sterilization of medical products- Surgical dressings, sutures, catheters, syringes
• Diagnosis (12-14 million procedures each year in U.S.)
- Technetium-99 extensively used for bone cancer, prostate cancer
- Imaging for heart, brain, lung disorders- Imaging for cancer tumors- Radioimmunoassay (determine levels of hormones,
vitamins, enzymes, drugs)• New drug testing
- Over 80% of all new drugs tested with radioactive tagging before approval
• Therapy- Decrease pain of bone cancer- Hyperthyroidism (20,000 patients/year)- Cancer (direct gamma, “smart bullets”)
Agriculture
• Reduce needs for fertilizers and water• Speed breeding of improved crops
[2,250 new crop varieties worldwide(89% radiation used)]
- Greater yield- Increased disease resistance- Better nutritional value
• Animal husbandry- Increase body weight- Vaccines to eliminate diseases
• Insect control- Sterilization (screw worm, Mediterranean fruit flies, gypsy moths)
• Food irradiation (76 million cases of food poisoning each year in U.S.)- Kill bacteria, molds, yeasts, parasites, insects- Extend shelf life
Co-60 food irradiator
Industry
• Tracers (pipeline leaks, malfunctions,wear, and corrosion)
• Thickness gauges (sheet metal,paper, textiles)
• Density gauges (oil and foodindustries)
• Imaging (weld inspection,non-destruction examination)
• Smoke detectors (unmatchedreliability)
• Lighting (airports, exit signs, traffic control)• Tires (vulcanize rubber)• Reduce static electricity (printing process,
paper making)Ir-192 gamma image
Environmental Protection
• Environmental pollution- Determine pollution
• Amounts and locations• Causes• Proper remedy
• Air pollution and global climate change- Uptake of greenhouse gases by plants
and the sea- Measure CO2 release by individual plants
• Water pollution- Measure CO2 levels in sea water (microscopic
phytoplankton aggregation)- Tracer technique for salt water/fresh water mixing;
cause of pollution• Soil pollution
- Identify pesticide and fertilizer decomposition product locations- Identify source of contamination
Public Safety and Basic Science
• Fighting terrorism- Luggage inspections- Anthrax in mail- Sensing clandestine weapons
testing- Sensing contamination releases
• Safety and Science- Airport runway lighting- Dating techniques (archeology,
etc.)
Tritium light
Californiumbased explosion
detection system
Space Exploration
• Electrical generation- Radio-Thermal Generators (RTG)
• Pu-238 excellent heat source (87.7 year half-life)
• Direct conversion to electricity (~7% efficiency)
- Dynamic Isotope Power System (DIPS)• Pu-238 still excellent heat
source• Rankine cycle active
system (~20% efficiency)• Prometheus Project
– For Deep Space missions >100 KW
Galileo
Cassini
Space Exploration
• Prometheus Project– For Deep Space missions >100 KW
Nuclear Power in Context of Spacecraft Applications
• Nuclear Fission Reactors and Radioisotope Thermal Generators
• Key operational features– Safe, Light, Long life– Enabling new methods of space exploration– Deliberate trajectories, high-power science, large band-width
communications– Wide area planetary surface coverage, independent of solar flux– Can withstand harsh environments
10-1
100
101
102
103
104
105
Elec
tric
Pow
er L
evel
(kW
e)
1 hour 1 day 1 month 1 year 10 years
Chemical
Nuclear Fission
• Nuclear Fission • Solar
• Radioisotope/dynamic • Solar
Solar • Radioisotope/passive • Solar
Duration of Use4035302520151050
0.0
0.5
1.0
1.5
2.0
Distance from Sun (AU)
Sola
r Ene
rgy
Flux
(Ear
th =
1.0
)
Earth
Mars
Jupiter
SaturnUranus Neptune Pluto
New Nuclear Science and Technology Program at the
University of Pittsburgh• Five course undergraduate
sequence in the School of Engineering.
• Permits an engineering baccalaureate major to get option in nuclear engineering
• Currently teaching “Introduction to Nuclear Engineering” to 72 undergraduates.
• Have concept approval for graduate courses in nuclear science and technology.
• Great support by Westinghouse and First Energy (Beaver Valley)
Renaissance Engineering• Be a changemaster,”
creating exciting new technologies.
• How about protecting our environment, improving our quality of life, and earning a good living at the same time?
Consider the opportunities!• Provide future electrical energy
systems such as advanced reactors, needed not only by the U.S. but also by developing nations for economic security and growth.
• Design power systems, nuclear propulsion systems, and radiation sources and detectors for deep space missions.
• Apply radiation for the sterilization of medical instruments and food processing equipment, and for food preservation.
Consider the opportunities!• Develop advanced radiation
sources and detectors for use in scientific research as well as in precision manufacturing.
• Apply radiation to diagnose and combat cancer and other diseases.
• Contribute to national security through the stewardship of nuclear weapons and engineering safeguards against nuclear proliferation.
E=mc2