1. Nuclear Technology
& Us
JUS 394 Arizona State University
Science, Technology & InEquality
Professor: Merlyna Lim

2. What IS Nuclear Technology
Images of our world
Weapons
Reactors
Nuclear waste
Hiroshima
Anti Nuclear Protests
Media bring nuclear technology to our attention
How to sort out the issues from the noise?

3. Nuclear POWER

4. Scientific Views
for easy introduction:http://
www.youtube.com/watch?v=fjgdgAhOzXQ
ENERGY -- the driving force of change
ENERGY -- heart of nuclear technology;
radioactivity, nuclear fission, and nuclear fusion
(reactions) are also driven by energy

5. Energy plays an important part
And it’s used in all this work;
Energy, yest energy with power so great,
A kind that cannot shirk.
If the farmer had not this energy,
He would be at a loss,
But it’s sad to think, this energy
Belongs to a little brown horse.
A school verse by Richard Feynman
a Nobel laureate for physics

6. Nuclear ENERGY
Energy forms -- transfer and conversion (recalling
your high-school physics class!!)
Part of nuclear technology -- for the conversion of
nuclear energy into heat and electric energy; its
development is related to the development of other
technologies
The Sun is a nuclear fusion reactor -- nuclear
technology imitates the energy producing process of
the Sun

7. Nuclear Fission
A process by which a heavy nuclide splits into two
of more pieces -- became the top secret in Germany,
England, the former USSR and the United States
Transuranium: Fermi (1901-1954) in Rome, F. Joliot
(1990-1958) and I. Curie in Paris, and Otto Hahn....

8. Nuclear Fission
Uranium isotopes -- 235U
How much energy is released per fission reaction?
How can the amount be estimated or calculated?
What are the applications of fission energy in war and peace?
235U to give two nuclides --> 117Sn50, and 118Sn50, their masses being
116.902956 and 117.901609 amu respectively. The mass of 235U92 is
235.043924 amu. The difference in mass: 235.043924 - (116.902956 +
117.901609) = 0.2394 amu (931.5 MeV/1 amu) = 223 MeV.
E=mc 2

9. Common Perceptions
http://www.youtube.com/
watch?v=MRC5KDqpZ_I
Are these images represent
“the truth” behind nuclear
technology?
We should understand our
own biases

13. Nuclear weapons: Can any rational person
make a case for their continued existence?
Nuclear reactors: if they are very dangerous,
can we afford to use them?

14. Nuclear Technology
&
MEDIA Representation

17. Radiation
As constructed
in the Media

20. Media Stories
Do I have to worry about radiation on airplanes?
Is flying like working in a nuclear power plant?
Does that mean nuclear plants are safe or flying
is hazardous?

21. Other Nuclear News

24. Radon

27. Radon Media Stories
What is it
Should I get my house tested?
Is it related to nuclear power?
Why didn’t someone tell me about it earlier?

28. RADIATION FICTIONS

29. Radiation Fictions
• Fear:
– “It’s gonna blow!!!”
• Controversy:
– “We’re all gonna die!”
• Misunderstanding:
– “It’s not natural!”
• Mistrust
– “They’re all liars. We know
mutant bugs will take over the
earth and enslave us.”

30. Nuclear Technology
Too little we know on ‘what it is’
Dominant perception (mainstream political stories, media
representation) reflect only partial truth
Preconceived notions can hinder clear thinking and fruitful
discussions
Don’t we need to understand the basis of the technology to
be able to come to ‘better’ decision?
Doesn’t public deserve more information?
Doesn’t public (us) need to be better informed?

31. Radiation Facts
It’s been around forever
First was noticed ~ 1895
A lot was learned since then:
– doctors & radiation could cure cancer
– quacks & radiation could kill people
– the Military & radiation could kill a LOT of
people

32. Environmental Radiation
• Radiation & radionuclides
older than the Earth
• Natural part of our
environment
• Radiation field varies by
geology, elevation, season,
living conditions

33. “Artificial” Radiation
• Medical
• Occupational
• Nuclear Fuel Cycle
• Fallout
• Petroleum Industries
• Power generation
• Other

34. Quanties & Units
• Amount (activity):
– Becquerel (Bq) dis/s
– Curie (Ci) 3.7 x 1010 dis/s
• Dose:
– gray (Gy) 1 J/kg
– rad, 0.01 Gy
• Dose equivalent

35. Range of Doses
General public - 360 mrem/y natural
Radon: 200 mrem
Other natural: 97 mrem
Remainder ~ 15 % medical, 3% products, 1% other
Medical procedures (per procedure)
CT head and body: 110 mrem

36. %Contribution to Dose
• Contribution of various radiation sources to total
average dose equivalent to persons in the United
States (NCRP, 1987).

37. Basic Facts
• Two main types:
– electromagnetic (X-rays and gamma rays)
– particulate (electrons, protons, alpha particles..)
• Produced in the nucleus or through atomic orbital
transitions
• Capable of ionizing (removing electrons) from
atoms

38. Electromagnetic
Wavelength
Frequency
Gamma Rays γ Photon Energy
X Rays
Ultraviolet Light
Visible Light
Infrared (heat)
radiation
Radio Waves

39. Radiation Particles - α
α, Helium-4 nucleus
(radon is a source)
β, nuclear electron
(40K is a source)
orbital electron

40. Types and properties of ionizing
radiation
Range in Soft
Types of radiation Relative mass & charge Tissue
Gamma Ray 0 0 centimeters
X-ray 0 0 centimeters
Beta Particle (electron) 0.0005 -/+ 1 millimeters
1 0 centimeters
Neutron
1 +1 microns
Proton
4 +2 microns
Alpha

41. Radiation Effects in Living
Nuclide decays
Emitted radiation ionizes
atom
OH Free radicals created
Cell/DNA attacked
Cell killed or damaged
dead cell ⇒dead organ
damaged cell
⇒cancer(?)

42. Routes of Radiation Exposure
External: β, γ, n
α, Internal: α, β, γ, n

43. Range of Radiation
Hormesis (a little is good for you)
Nothing
Impaired organ function
Cancer
Genetic (mutation in offspring)
Teratogen (impairment in offspring)

44. Factors Determining
Radiation type ( α, β, γ, n )
Duration of delivery (s → y)
Location (external or internal)
Distribution in / around body
Magnitude of dose

45. ‘predicting’
Radiation Effects
Why the “uncertainty”?
Not all effects are apparent
Knowledge limitations (likely impact)
Natural variations (radiation field changes)
Measurement ability (you can only go so low)
Dose is predicted

46. Radiation Effects Model
Real data
Potential Damage
to Health
is
h es
ot
yp Doses Causing
r H Observed Adverse
n ea
Li Health Effects
370 mrem 100,000 mrem
Area of controversy

47. Radiation Effects Data
Mainly for people or lab rats
Good data in high dose/high dose-rate region
Limited/contradictory data in low dose/low-
dose rate region
Some data suggest threshold (~10 rem)

48. What about other
Insects are tough to kill
Big trees are as sensitive as we are
So are most mammals
Fish and plants are about 10x more resistant
But…..
radionuclides are “more concentrated” lower in food
chain

49. Radiosensitivity of
Species Least
Most
Sensitive Sensitive
Micro-
organisms
Inverte-
brates
Plants
Fish
Amphibians
Birds
Mammals
Humans
10 100 1,000 10,000 100,000 1,000,000
Acute radiation dose, rads

50. So......
Radiation in high doses can kill you
Radiation in moderate doses increases your
cancer risk
Radiation at doses near or below background
may :
do nothing ???
help you ???

51. Should we sink ourselves in ‘the fear’ of
technology? Just based on too little
knowledge... of we have seen and heard?
Nuclear..... “clean technology”, how clean is
clean enough?
“a little bit of knowledge is a dangerous
thing.....”