I think my AIP Handbook may have a typo. It gives 15 mbarns for the 2200 km/s neutron absorption cross section for Pb-208 but it is doubly magic so 1.5 mbarns might be a better guess. http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/shell2.html If so, 100 m of travel gives a probability of 0.5 of absorption so our reactor might need a large diameter (20 m or more) to avoid losing too many neutrons. In this situation, neutrons may recross the proton/deuterium target region to a significant degree and so we should think about how the proton/deuterium target may act as a poison if it absorbs neutrons. Indeed, we might prefer deuterium as the projectile because it is less likely to absorb a neutron than a proton is.
Having a liquid catalyst should keep the lead and bismuth isotopes well mixed.
I spoke with John White at the NRC who says the pipe is steel with a wrap that is plastic. The pipe has to be dug up and disposed of as nuclear waste upon decommissioning according to White so it might make sense to remove all the underground elements now and replace them with above ground pipes since they are unreliable.
Plastic is used in some tritium applications: http://sti.srs.gov/fulltext/ms9900143r1/ms9900143r1.html Sound's like it has to be accessible since it becomes nuclear waste after the plastic degrades from the effects of th tritium. Thus, I doubt that the use of plastic pipes in this case could have been correct.
I would add now that in bulk materials there is some efficiency gain from running at higher illumination. In the present approach there is effectively higher illumination because the scattering material acts as a concentrator. Some benefit may carry over.
Agreed. Going to higher efficiency requires using multiple materials with different band gaps so far. However, this approach might might be generalized by including wires of other materials in the sparse matrix. Imagine including material with a lower energy band gap. If it is constructed to be reflective above the silicon band gap, then it is like so much more alumina in the fill material for those photons. Conversely, the silicon is transparent for photons below its band gap. So, when finally absorbed, the photons are segregated to their appropriate material. Usually, multi-junction uses the transparency of the high band gap material to pass lower energy photons through to a lower layer. You'd need to work out coatings to make the lower band gap material reflective in this case which is more complex but the reduction in material use might make it worth it.
Are plastic pipes rated for nuclear applications? http://www.timesargus.com/article/RH/20100227/NEWS04/2270342/0/NEWS02 Seems like weakening bonds with ionizing radiation in a hydrocarbon polymer might lead to oxidation and weakening of the material. Even UV seems to weaken it.
This is pretty wrong. Yes, there is some contribution from deuterium activation but mainly it is burnable poisons in the fuel assembly and ternary fissions that produce tritium in BWRs. In PWRs boric acid in the coolant is even more important. http://meetings.lle.rochester.edu/Tritium/documents/3.ppt
In the US we can get 40% of current net generation just using rooftops. Don't know where your 'blanketing large amounts of land' comes from. Perhaps you have been intentionally misinformed by nuclear power supporters. Also, the US onshore wind potential is nine times higher than current net generation http://www.energyefficiencynews.com/i/2842/ Much, much cleaner than nuclear power and much less expensive too.
They were designed to last 40 years. In the case of Vermont Yankee it is pretty clear that the design or execution or both were flawed since it is crumbling at the age of 38.
There was a pretty steady decline in US coal mining deaths until they plateaued around 2000. They might be heading down again now though. http://www.msha.gov/stats/centurystats/coalstats.asp The Mine Safety and Health Administration does try to learn from past accidents but coal mining remains an unsafe occupation. Things may also get worse as Appalachian coal declines in quality and mining gets more technically challenging or a shift to western open pit mining may help out.
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I think my AIP Handbook may have a typo. It gives 15 mbarns for the 2200 km/s neutron absorption cross section for Pb-208 but it is doubly magic so 1.5 mbarns might be a better guess. http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/shell2.html If so, 100 m of travel gives a probability of 0.5 of absorption so our reactor might need a large diameter (20 m or more) to avoid losing too many neutrons. In this situation, neutrons may recross the proton/deuterium target region to a significant degree and so we should think about how the proton/deuterium target may act as a poison if it absorbs neutrons. Indeed, we might prefer deuterium as the projectile because it is less likely to absorb a neutron than a proton is.
Having a liquid catalyst should keep the lead and bismuth isotopes well mixed.
There has been some nice work recently on what is available for uranium: http://www.physorg.com/news177839133.html Looks pretty scant. Unconventional gas has boosted estimated reserves here and in Europe quite a lot. Here is a description for the US. http://www.naturalgas.org/overview/unconvent_ng_resource.asp
There is some info on deuterium bombardment of Li as well http://www.iop.org/EJ/abstract/0031-9155/23/1/003
I spoke with John White at the NRC who says the pipe is steel with a wrap that is plastic. The pipe has to be dug up and disposed of as nuclear waste upon decommissioning according to White so it might make sense to remove all the underground elements now and replace them with above ground pipes since they are unreliable.
Some also use d-t fusion http://www.sciner.com/Neutron/Neutron_Generators_Basics.htm not sure spallation counts as conversion though. And, you are just shifting the coulomb barrier problem up stream.
I wasn't thinking. How about pion on deuterium capture for neutrons?
That one sounds like it won't work on energy conservation grounds.
Yes. The explanations though are less developed compared with the experimental evidence.
A friend of mine at NRL thinks it is a lattice effect http://www.lenr-canr.org/acrobat/ChubbSRresonantel.pdf
There is probably less energy remaining from uranium than from natural gas so the soon-it-will-all-be-gone problem is worse for uranium.
Don't know. could he still play leapfrog?
Might be some time. There do seem to be reproducible effects though.
Plastic is used in some tritium applications: http://sti.srs.gov/fulltext/ms9900143r1/ms9900143r1.html Sound's like it has to be accessible since it becomes nuclear waste after the plastic degrades from the effects of th tritium. Thus, I doubt that the use of plastic pipes in this case could have been correct.
The frog still gets the same effect when hopping. Also, you might want to start crossing cold fusion off the auto-mock list: http://www.lenr-canr.org/acrobat/BarnhartBtechnology.pdf
I would add now that in bulk materials there is some efficiency gain from running at higher illumination. In the present approach there is effectively higher illumination because the scattering material acts as a concentrator. Some benefit may carry over.
Agreed. Going to higher efficiency requires using multiple materials with different band gaps so far. However, this approach might might be generalized by including wires of other materials in the sparse matrix. Imagine including material with a lower energy band gap. If it is constructed to be reflective above the silicon band gap, then it is like so much more alumina in the fill material for those photons. Conversely, the silicon is transparent for photons below its band gap. So, when finally absorbed, the photons are segregated to their appropriate material. Usually, multi-junction uses the transparency of the high band gap material to pass lower energy photons through to a lower layer. You'd need to work out coatings to make the lower band gap material reflective in this case which is more complex but the reduction in material use might make it worth it.
There are parts of the oceans where storms are few and a lot of sunshine is available. This concept looks interesting: http://www.solar-islands.com/
Are plastic pipes rated for nuclear applications? http://www.timesargus.com/article/RH/20100227/NEWS04/2270342/0/NEWS02 Seems like weakening bonds with ionizing radiation in a hydrocarbon polymer might lead to oxidation and weakening of the material. Even UV seems to weaken it.
This is pretty wrong. Yes, there is some contribution from deuterium activation but mainly it is burnable poisons in the fuel assembly and ternary fissions that produce tritium in BWRs. In PWRs boric acid in the coolant is even more important. http://meetings.lle.rochester.edu/Tritium/documents/3.ppt
It is clearly a cover up since they were required to hold a public meeting about the incident. They failed to give any notice.
In the US we can get 40% of current net generation just using rooftops. Don't know where your 'blanketing large amounts of land' comes from. Perhaps you have been intentionally misinformed by nuclear power supporters. Also, the US onshore wind potential is nine times higher than current net generation http://www.energyefficiencynews.com/i/2842/ Much, much cleaner than nuclear power and much less expensive too.
That is evaporative cooling. Needs a large steady water supply. Artificial lakes are sometimes used as well.
Essentially the same point about cooling was rated interesting on another thread: http://slashdot.org/comments.pl?sid=1553308&cid=31279916
They were designed to last 40 years. In the case of Vermont Yankee it is pretty clear that the design or execution or both were flawed since it is crumbling at the age of 38.
There was a pretty steady decline in US coal mining deaths until they plateaued around 2000. They might be heading down again now though. http://www.msha.gov/stats/centurystats/coalstats.asp The Mine Safety and Health Administration does try to learn from past accidents but coal mining remains an unsafe occupation. Things may also get worse as Appalachian coal declines in quality and mining gets more technically challenging or a shift to western open pit mining may help out.