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Nuclear accident follows Japanese earthqauke
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Ippoippo



Joined: 24 Nov 2005
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Location: Bath->Tokyo->Cardiff-> Hokkaido, Japan next?

PostPosted: Wed Nov 02, 2011 1:30 pm    Post subject: Reply with quote

"New fission suspected at Fukushima nuclear plant"
http://www.japantoday.com/category/national/view/radioactive-gas-associated-with-fission-reported-at-fukushima-nuclear-plant

http://www.guardian.co.uk/world/2011/nov/02/fukushima-setback-signs-nuclear-fission

http://www.telegraph.co.uk/news/worldnews/asia/japan/8863967/Japan-signs-of-possible-nuclear-fission-at-Fukushima-plant.html
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biffvernon



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PostPosted: Wed Nov 02, 2011 2:54 pm    Post subject: Reply with quote

and http://cryptogon.com/?p=25810

So what they told us was impossible is happening after all!

Discussion at http://www.physicsforums.com/showthread.php?s=843a38205c62bf1dcac97cb7647a9651&t=480200&page=724
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An Inspector Calls
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PostPosted: Wed Nov 02, 2011 5:33 pm    Post subject: Reply with quote

What are you on about? Radiation is detected at Kukishima: therefore, there's fission. You can't have radiation without fission. So what's the news?

I suppose you're thinking of criticallity, but since the nuclear material isn't in a moderated configuration (assuming it's been melted down) it's difficult to see how it can go critical.
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biffvernon



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PostPosted: Thu Nov 03, 2011 7:10 pm    Post subject: Reply with quote

Re-criticality is exactly what the Xenon 135 levels indicate.

Quote:

Tokyo Electric Power Company, said that gas from Reactor No. 2 indicated the presence of radioactive xenon and other substances that could be byproducts of nuclear fission. The presence of xenon 135 in particular, which has a half-life of just nine hours, seemed to indicate that fission took place very recently....

But even in their most dire assessments, some experts had not expected even bursts of re-criticality to occur, because it was unlikely that the fuel would melt in just the right way — and that another ingredient, water, would be present in just the right amounts — to allow for any nuclear reaction. If episodes of fission at Fukushima were confirmed, Mr. Koide said, “our entire understanding of nuclear safety would be turned on its head.”


http://thinkprogress.org/romm/2011/11/03/360581/gone-fission-if-fukushima-nukes-are-seeing-fission-bursts-it-turns-our-entire-understanding-of-nuclear-safety-on-its-head/

The discussion by the physicists continues at http://www.physicsforums.com/showthread.php?t=480200&page=726
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An Inspector Calls
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PostPosted: Fri Nov 04, 2011 1:45 pm    Post subject: Reply with quote

No it doesn't, it indicates fission.

A reactor goes critical only when the replication of released, fission neutrons generation to generation reaches 1.

If it's below 1 the reactor is sub critical, if above it's super critical and the radiation levels will start to multiply (a key measurement then is doubling time which is why reactors are always fitted with doubling time trips).

But the reactor, if it has melted down, is no longer in a configuration where the fissionable uranium can achieve criticallity - it's lost the moderator and thus the quantity of thermal neutrons (as opposed to fast neutrons) has fallen.

These points are mentioned in the physics forum.

There may be zones in the melted lump where, as it cools, neutron replication increases from time as it physically shifts or if neutron absorbers, such as xenon, decay to other fission products. There's no new physics.
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biffvernon



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PostPosted: Fri Dec 02, 2011 9:11 am    Post subject: Reply with quote

The truth is leaking out from TEPCO, rather more slowly than the fuel did.

http://www.guardian.co.uk/world/2011/dec/02/fukushima-fuel-rods-completely-melted
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biffvernon



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PostPosted: Thu Dec 29, 2011 9:20 am    Post subject: Reply with quote

Here's an interesting video with the new Japanese prime minister explaining just what 'cold shutdown' means. He admits the most, if not all, the fuel melted and went through the floor and it's exact location and temperature are unknown. Cold shutdown means that the whole thing is generally under 100 degrees but that doesn't amount to 'control'.

http://www.youtube.com/watch?feature=player_embedded&v=MxUQKJwkIeY
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Ippoippo



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PostPosted: Sat Dec 31, 2011 9:24 am    Post subject: Reply with quote

This is rather worrying footage.

http://www.youtube.com/watch?v=kHXXa_QOET8
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biffvernon



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PostPosted: Sun Feb 05, 2012 8:13 pm    Post subject: Reply with quote

Getting on for a year on and the summing up accounts are emerging.

http://www.globalresearch.ca/index.php?context=va&aid=28870

Fukushima: A Nuclear War without a War

The Unspoken Crisis of Worldwide Nuclear Radiation

Michel Chossudovsky (Editor)
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PS_RalphW



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PostPosted: Fri Feb 24, 2012 10:27 am    Post subject: Reply with quote

Quite a good documentary on BBC2 last night, probably on iplayer now.

Extended interviews with workers, politicians and management, about how close the reactor cores came to exploding, and the release of spent fuel in one of the explosions, and at one point the director of the plant called for its total abandonment, ordering all staff to leave, as he saw total meltdown as unavoidable.

No discussion of what the current status is, or what next... implied a 20 year exclusion zone in the immediate area.

http://www.bbc.co.uk/programmes/b006mgxx

Inside the Meltdown


Last edited by PS_RalphW on Fri Feb 24, 2012 10:43 am; edited 1 time in total
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JohnB



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PostPosted: Fri Feb 24, 2012 10:36 am    Post subject: Reply with quote

RalphW wrote:
No discussion of what the current status is, or what next... implied a 20 year exclusion zone in the immediate area.

Probably a good thing I don't live much less than that distance from Hinkley Point any more!
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biffvernon



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PostPosted: Sat Mar 10, 2012 11:13 am    Post subject: Reply with quote

Life in Japan a year on as the world's biggest clean-up is attempted.

http://www.bbc.co.uk/news/world-asia-pacific-17321936
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biffvernon



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PostPosted: Sat Mar 10, 2012 6:44 pm    Post subject: Reply with quote

And a nice little film via People Tree: http://www.youtube.com/watch?v=tLSiJDO99c4 with some interesting insights into how folk are coping, the media and how to cope without nuclear power.

Part 2: http://www.youtube.com/watch?v=fqZDvWtHOb8
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biffvernon



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PostPosted: Sat Mar 24, 2012 8:27 pm    Post subject: Reply with quote

More devious goings on: http://www.youtube.com/watch?v=Wn6I6dj8PlA
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biffvernon



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PostPosted: Tue Mar 27, 2012 7:46 pm    Post subject: Reply with quote

Problems at the site rumble on: http://www.palmbeachpost.com/news/world/2264059.html
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