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March 17

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How often does Sansevieria trifasciata bloom?

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How often does Sansevieria trifasciata (snake plant) bloom? My mother has one that is blooming now and she says that it is rare. Bubba73 You talkin' to me? 01:04, 17 March 2011 (UTC)[reply]

When grown as a houseplant, the period between blooms is highly variable, based on sun exposure, and how root-bound it is in its container. I'm sure you could not see a bloom for several years in some cases, especially if starting from a small clone in a large pot. Under 'average' houseplant conditions for a mature individual, expect a bloom every 2-4 years. They are more likely to bloom the more root-bound they are, because this is when they have reached the limit of vegetative growth. Note that it spreads rapidly through clonal growth in its natural environment, so sexual reproduction every year is not critical for long-term population success. Also, as a side note they have nectaries on the base of each flower on the raceme, which each produce a large drop of sweet nectar. Your mother may enjoy trying some; it tastes much like honey :) SemanticMantis (talk) 02:32, 17 March 2011 (UTC)[reply]
This one is in a small pot but it gets plenty of sunlight (next to a picture window). Mother says that she has never seen one bloom. She had me take photos to show the women in the beauty shop to prove that it does bloom. Bubba73 You talkin' to me? 02:58, 17 March 2011 (UTC)[reply]
I should have flagged (OR) above, maybe 2-4 years is a bit optimistic, as it is in the same family as the century plant, which is known for its long bloom interval. The bloom definitely feels special when it happens. SemanticMantis (talk) 14:00, 17 March 2011 (UTC)[reply]
That helps explain it, thanks. Bubba73 You talkin' to me? 15:37, 17 March 2011 (UTC)[reply]

Scent

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I'm a hunter and I know how good an animals sense of smell is. My question is, all else considered, does hair make it easier for an animal to smell you? I heard it helps to vaporize it, which sounds bad, as that odor no doubt travels.

Any help would be appreciated, and if you know of any odor blockers (not stuff that leaves you smelling like perfume, but true blockers) I'd be much obliged. —Preceding unsigned comment added by 148.61.220.214 (talk) 01:08, 17 March 2011 (UTC)[reply]

Body odour is increased by the presence of pubic hair. That has even been proposed as the reason we have pubic hair. --Tango (talk) 01:24, 17 March 2011 (UTC)[reply]
Maybe for our naked cave-dwelling fore-bearers, but wouldn't the clothing of a hairless human absorb and hold odors just as well as, if not better than, body hair?
I assume he's not talking about shaving his body and then going out into the woods nude. APL (talk) 02:11, 17 March 2011 (UTC)[reply]
Here's a blog called ArcheryTalk that discusses this issue from a bowhunter's perspective. The author discusses five main strategies in further detail there:
  1. Cleanse – Your body……..
  2. Neutralize – Odor causing Bacteria…….
  3. Maintain – Clean clothing/footwear…….
  4. Mask – We’ll talk about this one……
  5. Play the wind – Enough said………
He "neutralizes" by scrubbing down with an antiseptic like Betadine, and claims that a product called 'Bob’s “Skunk Essence”' works as an effective mask for him.
Also, as far as hair-odor-blockers, here's a plug for the product Invisible Hunter Shampootm:
"Sometimes overlooked, human hair carries odors from not only one’s own body but from other environments that one has visited. A good practice of shampooing with Invisible Hunter’s Scent–Removing Shampoo is all you need to eliminate dirt and odors. Invisible Hunter’s Scent-Removing Shampoo will leave your hair clean and soft while providing you the extra scent control the serious hunter seeks."
WikiDao 04:20, 17 March 2011 (UTC)[reply]
Just curious, how do you get rid of the skunk essence smell. Great in the woods, real bad at home! Richard Avery (talk) 12:00, 17 March 2011 (UTC)[reply]
Real hard-core hunters wouldn't care about that. Real hard-core hunters are also probably single. (If not, see No true Scotsman) :-) . {The poster previously known as 87.81.230.195} 90.197.66.165 (talk) 01:48, 18 March 2011 (UTC)[reply]

Thanks, all. I like your comment though that clothes themselves would be a big issue...Do you know some products specific to cleaning your clothes, but not leaving it smelling like Tide, either? Thanks again. —Preceding unsigned comment added by 148.61.220.214 (talk) 03:25, 18 March 2011 (UTC)[reply]

More examples of millisievert doses?

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I am skeptical of Sievert#Yearly_Dose_Examples-- for example, how could "some parts of Iran" naturally have half the carcinogenic dose? Can anyone find a good source for this kind of information? Shii (tock) 01:10, 17 March 2011 (UTC)[reply]

What you are calling the "carcinogenic dose" is the dose at which the probability of you getting cancer is measurably higher than normal. It isn't much higher, though. It is still an insignificant dose as far as individuals are concerned (other factors, such as diet and lifestyle, affecting cancer cause far more variation from person to person). When you look at a large number of people, it becomes significant, but only just. --Tango (talk) 01:21, 17 March 2011 (UTC)[reply]
Seems reasonable to me. Why do you find that so surprising? Dauto (talk) 03:01, 17 March 2011 (UTC)[reply]
The figure "Background radiation in parts of Iran, India and Europe: 50 mSv/year" sounds somewhat high to me, even though it comes from a BBC source - a value that high must be very localised. Our article on Ramsar, Mazandaran says "Some areas around Ramsar have the highest level of natural radioactivity in the world, due to the presence of radioactive hot springs ... the medium value in the Ramsar area is 10.2 mSv/year" - although background radiation levels in and around the springs themselves can be much higher. Gandalf61 (talk) 07:12, 17 March 2011 (UTC)[reply]

Full meltdown?

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According to this, http://www.cnn.com/interactive/2011/03/world/interactive.nuclear.japan/index.html?hpt=C2

Three mile island and Chernobyl were only partial meltdowns. What's a full meltdown? This never happened? I always thought Chernobyl was a full meltdown. How far deep can a meltdown melt through stuff? ScienceApe (talk) 02:50, 17 March 2011 (UTC)[reply]

Nuclear meltdown refers to the heating of the Nuclear reactor core to the point where it melts; i.e. turns to a liquid. In a partial meltdown, parts of the core would melt, and other parts would remain intact. In a total meltdown, the entire core would be a pool of liquid at the bottom of the reactor; AFAIK this has never yet happened. In Chernobyl, the problem wasn't no much a meltdown, which is a serious but managable event, it was the excursion (i.e. the fissile material reached criticality) which damaged the containment security in the plant and allowed radioactive material to be sent into the atmosphere. Indeed, our article on the Chernobyl disaster doesn't even mention a meltdown, except briefly in passing. Indeed, an excursion (basically the reactor turns into a bomb) is a far more serious event than a meltdown; once the reactor core exploded, whether or not it melted is somewhat moot. --Jayron32 03:01, 17 March 2011 (UTC)[reply]

Side-questions: I'm kind of kidnapping this question, but the questions about nuclear reactors are a hot (sorry for the pun) topic this week. So, here for the questions: (1) if we let it meltdown, wouldn't this bore a hole and let the atomic material slip through this hole, and in the same process, cover it with other molten substances? Sounds pretty optimistic, I know. (2) Have anyone let a small core meltdown to test the question (1)? (worse experiments indeed happened) Quest09 (talk) 18:15, 17 March 2011 (UTC)[reply]

1. Probably not. I mean if you put a pile of melted nuclear fuel it might burn down into the earth, but unless the nuclear pile is actually vaporizing everything it touches, how is the dirt and rocks and such going to get out of the hole? Plus all the stuff you are melting is becoming radioactive at the same time. 2. I would really, really hope not. That sounds like a very expensive experiment with potential to cause enormous environmental damage and large negative impacts to human health and for what real purpose? Googlemeister (talk) 19:00, 17 March 2011 (UTC)[reply]
See corium. Once the fuel melts, you get a radioactive slag of fuel oxides plus everything else the fuel encounters. If the molten corium encounters water (say, the suppression tank underneath the reactor) you get a steam explosion that spreads a radioactive dust over a huge area. --Carnildo (talk) 23:29, 17 March 2011 (UTC)[reply]

Earths axis

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Does the 6.5 inch shift in the earths axis from the earthquake create any changes, such as change in seasonal patterns or tides? —Preceding unsigned comment added by 68.36.96.146 (talk) 03:02, 17 March 2011 (UTC)[reply]

The circumference of the earth is roughly 40,000,000 meters. 6.5 inches is .1651 meters. .1651/40,000,000 = 0.0000000041275 or 4 parts per billion variation. That's pretty imperceptible. --Jayron32 03:08, 17 March 2011 (UTC)[reply]
In a related note, I've been trying to find out which way it's shifted. Here in Connecticut, am I closer or farther from equator? APL (talk) 07:36, 17 March 2011 (UTC)[reply]
It means Mrs. Claus is yelling at Santa to get his fat ass off that Nintendo game and go out there and move that pole! Wnt (talk) 17:14, 17 March 2011 (UTC)[reply]

Jayron, thanks for enlightening us on the imperceptibility of 6.5 in. in relation to the circumference of the earth. Does someone else care to answer the straightforward question? it obviously is different that before, so what does that difference equate to in more or less sunlight each day for the northern hemisphere? —Preceding unsigned comment added by 165.212.189.187 (talk) 17:28, 17 March 2011 (UTC)[reply]

The Earth's axis already shifts seasonally (at a greater magnitude than caused by the Earthquake, I believe), due to the rearrangement of mass caused by the weather (mostly the redistribution of water, I believe). Here are a couple articles on it, though they relate more to the change in day length than the axis shift [1], [2]. As these articles point out, pretty much every earthquake redistributes the mass at least some, but you can also see that the changes are on par with the yearly variation that is experienced anyway, regardless of earthquakes. The answer is definitely "no", this Earthquake will not have a noticable effect on seasonal patterns or tides. Buddy431 (talk) 18:03, 17 March 2011 (UTC)[reply]
Addendum: Here's a source that explicitly addresses the axis shift issue: the Earth's axis shifts about 3.3 ft seasonally, about 6 times the shift caused by the quake. Richard Gross, a Geophysicist, says "These changes in Earth's rotation are perfectly natural and happen all the time. People shouldn't worry about them." [3] Straight from the mouth of a real scientist. Buddy431 (talk) 18:07, 17 March 2011 (UTC)[reply]

This shift is in addition to the regular shift of the seasons. Who said anything about worrying, what did he say about curiosity, that it killed the cat? That is why this desk exists - to inform and enlighten not easy worrys of. —Preceding unsigned comment added by 165.212.189.187 (talk) 18:24, 17 March 2011 (UTC)[reply]

And it's doing a great job - who knew that the Earth's axis moves? Or that there was both an axis and a figure axis to keep track of? Wnt (talk) 23:32, 17 March 2011 (UTC)[reply]

Storing electricity via “counterbalance” batteries?

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Some time ago, I asked about the viability of using dams to augment sporadic electricity production via windmills and solar panels. The method is used in Sydney. When more than enough power is being produced, the power not needed is used to raise water to storage dams, where it can later be used to create hydroelectric power. This is, in effect, a battery, and I was surprised that it returned about 70% of the power it took to raise the water. Now, there are other ideas for batteries, as not all that many sites have big dams nearby.

My idea is: when the wind is strong and more power than is needed is being produced, why not have the mill raise a heavy weight chained below the vanes? When power is needed later, the weight can be slowly lowered, turning the vanes via gears and generating electricity.

I did read in New Scientist, years ago, in one of their historical featurettes, that in the early 20th Century, there were at least some English farmhouses which had a wind mill such as I have described on their thatched roofs. When the vanes turned, they could raise a weight, enclosed by a cylindrical cage located in the main room. When the wind died down, that weight could be allowed to slowly descend, generating electricity. I can’t find that source now, and I am wondering if someone knows anything about such an ingenious contraption. Myles325a (talk) 03:57, 17 March 2011 (UTC)[reply]

The idea's good - but the "engineering details" are hard. Gravitational potential energy is usually approximated as mgh - so pick some reasonable numbers for a mass (let's say, 10 tons), and a tower height (say, 100 meters); how much energy is that going to actually store? About ten megajoules of gravitational potential energy - about 3 kilowatt-hours. And that's a huge weight, and a really tall tower! Now, consider that one single barrel of oil contains (in the form of chemical energy) about one-thousand times as much energy as our massive 10,000kg, 100-meter-tall contraption!
To store a lot of energy in the form of gravitational potential energy, you need a lot of mass - which is why pumped storage hydroelectric is the only practical way to do it. Nimur (talk) 04:29, 17 March 2011 (UTC)[reply]
Myles325a's suggestion was used in practice for a couple of centuries in the longcase clock. I agree with Nimur that the attraction of using water is that vast amounts of it are available, and can be pumped into elevated storage. Solid components that could be used for storage of energy are miniscule compared with the mass that is available as water. Dolphin (t) 04:34, 17 March 2011 (UTC)[reply]
The use of such dams is not fondly regarded by environmentalists. Realize that such a system creates a large body of water without a shoreline, but just a large muck zone that is irregularly covered by water. Wnt (talk) 04:51, 17 March 2011 (UTC)[reply]
A similar system installed on a tidal shoreline can be more than 100% efficient (in effect) if the seawater is pumped up at high tide and used to generate electricity at low tide. On a coast with a big variation in times of high tide (such as the UK) such a system would be economically beneficial, though environmentalists would not be happy (but very few people are happy to have any generation scheme in their back yard!) Dbfirs 13:46, 19 March 2011 (UTC)[reply]
Grid energy storage covers almost all options for power storage. Instead of raising a weight with a windmill, pumped storage (already mentioned) and flywheel storage seem more viable. Zunaid 13:18, 21 March 2011 (UTC)[reply]

What exactly is the reason for the radioactivity?

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I'm a little confused after having read Fukushima I nuclear accidents. If the containment vessels are indeed all intact, what exactly is the source of the radiation that has been detected? Is the problem that water within the containment vessel is being made radioactive as it flashes into steam and gets vented (as an emergency measure) because the pressure within the containment vessel is high enough? Wouldn't this mean the vented steam is riddled with decay products? I'm not very clear on whether this reactor design has water pumped directly at the fuel rods so there's essentially direct contact between the fuel rods and the water that gets flashed into steam and then spins the turbines. On reflection, I suppose it must. Doesn't this mean that these "containment vessels" aren't actually able to be sealed? Comet Tuttle (talk) 06:26, 17 March 2011 (UTC)[reply]

The main thing is that spent nuclear fuel is kept in open ponds with very little containment. That's where most of the radiation has come from - there's a lot more to be released from there than from the reactors themselves. This is mostly slovenliness - there are other countries which have moved largely to dry cask storage. It is well known that in any natural disaster (such as a major pestilence or all-out civil war) anywhere in the world, which would cause nuclear reactors to go unattended, eventually the reactor will shut down, the diesel backup will run out, and the spent fuel pools will go Chernobyl at every unattended site. In addition, the containment for #2 is cracked.[4] Wnt (talk) 06:46, 17 March 2011 (UTC)[reply]
I only know of the Pebel bed reactors not using Spent fuel pools for the first few months or years. The heat generated for the first few half lives of the fast decaying isotopes is in an order of magnitude that all other methods are impractical. Most reactors store the spent fuel close to the reactor, this might change after the disaster.--Stone (talk) 07:22, 17 March 2011 (UTC)[reply]
I don't think it is "slovenliness" that dictates whether one uses wet storage. For one thing, Japan reprocesses — that usually dictates against dry storage. In any case, you need to store it in wet storage for awhile (at least a year) before you do anything else with it, so the really nasty stuff burns itself out. It's unclear to me how "old" the fuel in the wet storage is (you could calculate it if you knew the time between refuelings and the amount of spent fuel in there). --Mr.98 (talk) 15:01, 17 March 2011 (UTC)[reply]
Would someone more reliable than Wnt on physics-related subjects please confirm or deny what (s)he wrote above? Especially the claim that active cooling is the only defense against a Chernobyl-like disaster at any nuclear plant with a spent fuel pool? The article seems to say that this is false, but I don't know what to believe any more. -- BenRG (talk) 08:20, 17 March 2011 (UTC)[reply]
Yah I don't think he's right about that. Even if you left the reactor completely alone it wouldn't go Chernobyl. Especially once the control rods are in place a real catastrophe is pretty much impossible - and those rods are designed to fall into place at any disruption. It may melt down, but it will stay inside the containment. And the urnanium in storage can't go Chernobyl either. However it does seem that the containment pools are a weak spot. People paid a ton of attention to reactor design, and it looks like their designs worked. However the pools did not receive as much attention and most of the current problems (fires) are from those. Spent fuel pool#Status implies that someone noticed the problems and new designs are better. I have to assume that the Japanese fuel is not designed this way. Ariel. (talk) 09:03, 17 March 2011 (UTC)[reply]
To clarify, I used "go Chernobyl" to mean "produce all kinds of radioactive smoke and fire", not "break the reactor containment". I thought I was being clear there that the radiation would be coming from the pools. Wnt (talk) 10:34, 17 March 2011 (UTC)[reply]
Fukushima I nuclear accidents says:
"The nuclear fuel requires 1–3 years of constant active cooling (by flowing water) before the decay heat production gets low enough that effective passive cooling becomes sufficient to avoid excessive heating up to temperatures where the integrity of the fuel is at risk."
"At the time of the earthquake unit 4 had been shut down for maintenance and refueling since 30 November 2010. All fuel rods had been transferred in December 2010 from the reactor to the spent fuel pool on the top floor of the reactor building where they were held in racks containing boron to damp down any nuclear reaction. These recently active fuel rods were hotter and required more cooling than the spent fuel in units 5 and 6."
and mentions speculation "that the Fukushima management could have been engaged in an unsafe industry practice of re-racking spent rods in the pool well beyond its rated capacity, in effect heightening danger of melting and pool boil-off". Gandalf61 (talk) 09:51, 17 March 2011 (UTC)[reply]
So, the with problem with the spent fuel pools is that they are not contained . Also the fuel rods are still relatively rich in fissionable fuel and the racks that should hold them upright and provide some necessary separation to prevent criticality coming about, have been subjected to several server shakeings. If some off these racks (and any other safety devices like boron separation sheets) have been badly damaged or collapsed by the quake, then the evacuation of the local population seem like a very sensible step to take. The fuel may not be combustible but it can possible go critical again, given the right circumstances and until they can dump a lot of boric acid into the pool, there may still be enough water to facilitate this.--Aspro (talk) 10:13, 17 March 2011 (UTC)[reply]
I suspect, but do not know for sure, that criticality is not the major concern with the spent fuel at this point. I suspect that they would need to really be in a very poor state (e.g. melted sludge) for that to be an issue. The bigger problem is that they are very hot and full of very nasty things, and could catch fire, vent, melt, etc. --Mr.98 (talk) 15:31, 17 March 2011 (UTC)[reply]
Radiation is still being released by the venting of steam from reactors 1 and 3 (and 2 which may not even be contained). This radioactivity was observed before any issues arose with the spent fuel pools at 3 and 4. However, this radioactivity was a lower level (didn't require removing plant workers) and was blowing out to sea at that time. 75.41.110.200 (talk) 14:42, 17 March 2011 (UTC)[reply]
Thank you all for your responses. A followup question: Is it known whether the spent fuel at the site is recently spent fuel, or has some of it been sitting there in a swimming pool for a couple of decades? Mr.98 mentioned that Japan reprocesses their fuel, so it sounds like it's probably recent; but do we have an article on the lifecycle of fuel uranium and plutonium in Japan? Comet Tuttle (talk) 16:25, 17 March 2011 (UTC)[reply]
I doubt we have an article on it. It should be information that is "out there" though — it's the kind of thing the IAEA would know definitely. My mangled German + Google Translate of this article seems to indicate that there are 50, 81, and 88 tons of fuel rods in the three pools, but that this is not their full capacity, and in fact they are relatively empty. (By comparison, the spent fuel at some US reactors is around ten times that amount — because we don't reprocess, and we don't have any long-term waste disposal options worked out.) This suggests to me that they are pretty recent, but I'm not sure. --Mr.98 (talk) 17:31, 17 March 2011 (UTC)[reply]
The most resent rods were removed in November and December. These two pages out line the problems. Danger of Spent Fuel Outweighs Reactor Threat . I guestimate that a 13 foot long rod must weigh about 5 or 6 2½ to 5 hundredweight. Zirconium alloy is a wondrous material and hopefully it will resist the contents of the rods or the pellets themselves from forming a 'pile' on the floor. If not, then it wont just be the cherry bosoms glowing in the sunset this spring and Japan will be off my itinerary for the foreseeable future. Came across this handy little chart showing the current state of play at a glance. Status of nuclear power plants in Fukushima as of 16:00 March 17--Aspro (talk) 18:18, 17 March 2011 (UTC)[reply]
I don't think you need to be flip about the risks (cherry "bosoms" and etc.) — there are real people's lives here at stake. We are not quite in the "joke about it" stage yet. --Mr.98 (talk) 19:59, 17 March 2011 (UTC)[reply]
And if I had worded the possible out come more accurately would you have then accused me of over exaggeration and scaremongering? --Aspro (talk) 21:09, 17 March 2011 (UTC)[reply]
In fact, no. I think your comment was in extremely bad taste. That's a different category from whether I think it was accurate or not. --Mr.98 (talk) 21:34, 17 March 2011 (UTC)[reply]

DANGER WILL ROBINSON! DANGER! DANGER! The THOUGHT POLICE are EVERYWHERE!! (and Mr.98 ALWAYS has to have the last word) I personally am looking forward to those delicious sushi legs and BBQ frogs wings! YUM220.233.166.18 (talk) 07:16, 1 April 2011 (UTC)[reply]

Iodized salt instead of iodide tablets

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I have seen recent news stories about paranoid people hoarding potassium iodide tablets. I know that iodized salt is widely used for cooking, and contains either potassium iodide or sodium iodide (the two shouldn't really matter, right, since they all just disassociate to iodide ions in solution), couldn't one achieve the same effect by eating a lot of iodized salt? Or is there insufficient quantity of iodide in iodized salt? --98.210.210.193 (talk) 06:55, 17 March 2011 (UTC)[reply]

Right! My salt contains 0.0025% of potassium iodate. 1g would than be 2.5mg. Somebody said that a dose can be above 100mg of potassium iodate. This would be 40g of table salt. This is a deadly dose of salt for children and very unpleasant for adults. --Stone (talk) 07:33, 17 March 2011 (UTC)[reply]
The concentration apparently varies in iodized salt in important ways. I just read that Switzerland raised its concentration to 20 mg/kg from 15 mg/kg - your container appears to be just 15 mg/kg. Fortunately the article Thyrosafe I started is still knocking around, despite being deleted last December :( :), so I can see that the tablets are 130 mg for adults or 65 mg for children. So a child's dose of iodized salt required would be just, 8.6 kg?! Hmmm, I think you missed the % up there when you did the math before, unless I just fouled up.
Right! I missed the %. --Stone (talk) 13:52, 17 March 2011 (UTC)[reply]
Ooops, I messed up myself - the pills are labeled for 130 mg of KI, not 130 mg iodine, so it's only equivalent to 6.6 kg of iodized salt. If you pace yourself.... ;) Wnt (talk) 16:00, 17 March 2011 (UTC)[reply]
Anyway, since it's not needed in the U.S. where the crazy rush is, tossing a pinch of iodized salt over your shoulder would do no harm. And maybe that 8.6 kilogram figure will make people think twice about hammering their poor thyroids with that kind of iodine for no reason. Wnt (talk) 07:44, 17 March 2011 (UTC)[reply]
Can we react Tincture of iodine with something commonly available (baking soda?) to make sodium or potassium iodide? Ariel. (talk) 09:17, 17 March 2011 (UTC)[reply]
Just don't react it with ammonia or you'd get a pill with a kick to it. No, scratch that, I would say don't try this at all! Who knows what kind of impurities you'd choke down, not the least of which being iodine itself. But as you know, I'm not giving medical advice here. Wnt (talk) 10:30, 17 March 2011 (UTC)[reply]
"Japan radiation fears spark panic salt buying in China" -- Finlay McWalterTalk 15:08, 17 March 2011 (UTC)[reply]

Would eating some tinned fish or other seafood be of any use in an emergency situation? (Seafood - contains iodine). 2.97.215.199 (talk) 23:42, 17 March 2011 (UTC)[reply]

Well, for edible seaweeds e.g. kelp: "12 different species of seaweeds were analyzed for iodine content, and found to range from 16 microg/g (+/-2) in nori (Porphyra tenera) to over 8165 +/- 373 microg/g in one sample of processed kelp granules (a salt substitute) made from Laminaria digitata.";[5] "Edible seaweed contained I levels of between 4300 and 2,660,000 micrograms/kg";[6] (summarizing these two) "the average iodine content of kelp of 1,500 to 2,500 μg/g".[7] So we're looking at roughly 2 mg of iodine per gram of kelp (I assume these are all dry weight), if you happen to get an average sample, with a just ridiculous amount of variation. So eating 65 grams, a plausible dose, would be equivalent to the 130 mg tablet - though you might end up getting four times as much if you are unlucky. Or you might get less than a mg. Wnt (talk) 02:38, 18 March 2011 (UTC)[reply]
My ex (who is a third year undergraduate) has made over $1000 selling KI on eBay... John Riemann Soong (talk) 18:48, 19 March 2011 (UTC)[reply]

Why does the World suffer from nuclear phobia?

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Ever since Chernobyl, people have had a strong irrational fear of nuclear power. The public prefers coal fired power plants over modern ultrasafe nuclear powerplants, even though the dangers of global warming are far, far worse than that of a Chernobyl-type disaster. People are now fleeing Tokyo in airplanes, when merely being aboard the airplane at 40,000 feet altitude will expose people to 100 times more radiation than they would get if they were to stay in Tokyo. How can we explain this irrational behavior? Count Iblis (talk) 16:45, 17 March 2011 (UTC)[reply]

Just because the reading on a Geiger counter is the same doesn't mean the exposure is the same. In an airplane, you get off and the exposure ends. But in Tokyo the counter would be clicking due to various isotopes in the air, water, environmental surfaces which you might inhale or ingest and become exposed to for years to come.
Still, I think it is reasonable to assume many of the people fleeing are convinced that the radioactivity will become much worse, or that basic necessities will become even harder to find than they are now. After all, many people would have left the tsunami-disrupted country even without a nuclear situation. Wnt (talk) 16:52, 17 March 2011 (UTC)[reply]
Your premise is that people's fear of the ongoing nuclear crisis is irrational, but you would have to cite a source for that. What makes you think it is irrational? The actual situation at the site is very unclear; right now, nobody in the world, including you, can even assess the probability of Tokyo becoming increasingly irradiated, or of a criticality accident, in the coming week; and the Japanese government's and Tokyo Electric's shameful avoidance of disturbing the public with the scary details they do have only exacerbates the (rational, I'd argue) fears that already exist. Comet Tuttle (talk) 17:07, 17 March 2011 (UTC)[reply]
(ec) A better question would be why people have an irrational belief in the safety of nuclear power. Put simply, nuclear power isn't safe and it never has been. Even when operating correctly, nuclear power plants produce radioactive waste that will be dangerous for the next 10,000 years. A Quest For Knowledge (talk) 17:08, 17 March 2011 (UTC)[reply]
I think the question is why people seem to be more afraid of a rare leak of radioactive carcinogens from a nuclear plant than they are of the routine dumping of radioactive carcinogens into the air by coal plants; and seem to be more upset about a 1% increase in lifetime cancer risk for the nuclear workers than about the horrible lung diseases and fatal accidents that routinely afflict coal miners; and seem to be more afraid that a nuclear plant will render a hundred square kilometers uninhabitable than that coal plants will stop the gulf stream and render all of Western Europe unsuitable for agriculture. People do worry about those things, but I'm not sure that will stop them from demanding the closing of nuclear plants after this disaster, which will inevitably (as far as I can tell) lead to an increased demand for fossil fuels at a time when we desperately need the opposite. That's my fear. -- BenRG (talk) 20:15, 17 March 2011 (UTC)[reply]
There is quite an advanced literature on risk perception, esp. in relation to nuclear power. In particular you might find the work of Paul Slovic quite interesting — he charts out how fears of technology generally chart onto two axis: "unknown risk" and "dread risk". "Unknown risks" are things that are invisible hazards, with delayed effects, or exceptionally new. Think contamination, poisoning, irradiation. "Dread risks" are global, uncontrollable, catastrophic, involuntary. Think big disasters, or small disasters that you feel like you can't control. If you plot out how people judge various hazards on this scale, you get a nice graph of risk perception. On the bottom left (low dread, low unknown) are actually some quite dangerous things: bicycles, home electrics, automobiles, smoking (all things with very local effects, where you feel "in control", where by itself, one "accident" isn't going to kill more than a person or two). On the top right (high dread, high unknown) sits all of the radioactive fears (waste, weapons, meltdowns) — they trip up our psychological systems in a big way, and we've always viewed them (even before nuclear power) in rather mythological terms. Humans have ancient stories about evil rays, contaminated lands, and deformed children — the nuclear threat fit into these fears quite nicely. (On this point, my favorite book on the subject, though it is now a few decades out of date, is Spencer Weart's Nuclear Fear: A History of Images.) Note that I have generalized quite a bit regarding that chart. Weapons actually are somewhat less "unknown" than waste/power related things.)
None of this is correlated at all with what we might call actual risk (which can be tricky to calculate, but let's assume it exists). (This is not to say that all things considered dangerous are safe, or vice versa. Just that there isn't necessarily a meaningful correlation here in any individual case.) It is psychological. It is not a straightforward case of people not being "educated" enough on actual risks — that can itself backfire quite heavily (if you say, "it's safe, it's safe, it's safe!", and you're wrong in a BIG WAY one time... then your credibility is shot, and it's worse than if you hadn't said anything). Anyway, it is an interesting field. Whether people's risk perceptions are "rational" or not is entirely beside the point: human beings are not "rational" when it comes to our fears, and wishing they were will never make that so. --Mr.98 (talk) 17:15, 17 March 2011 (UTC)[reply]
An excellent way to assess risk in a rational way is to attach a price tag to it and see what a free market does with it. It's called the insurance industry and they're pros at weighing the cost of paying a claim versus the likelihood of having to do so.
When private companies in the USA wanted to start operating nuclear plants they asked insurance companies to take on some of their risk. The pros at the insurance companies looked at the payout vs. likelihood equation and said "no thanks". The industry should have ended there, but unfortunately it was important enough to national self-esteem that Uncle Sam stepped in and said "you guys just stash away a little money for minor accidents and if shit ever hits the fan my taxpayers will pick up the tab".
When the nuclear industry can cover its own risks then you can fairly claim that its skeptics are irrational. --Sean 18:12, 17 March 2011 (UTC)[reply]
Sean, nobody wants to insure against rare, large losses because that's risky. Insuring against many frequent, small (at the scale of the insurance company) losses is safe; you can build a business on that. The market is great at some things, but it's terrible at pricing rare, long-term risks. The actual, scientific cost of nuclear power versus the alternatives is such that we have to keep building nuclear power plants. The government steps in in these situations because that's why governments exist: to do the things that the market does badly. I know there are people who believe that the market does everything well and governments should be abolished, but those people are wrong, just like the people who think that homeopathy works, etc. This is the science desk. -- BenRG (talk) 20:15, 17 March 2011 (UTC)[reply]
I'm pretty sure those people fleeing Tokyo are actually at a greater risk of being injured getting to the airport or the train station, than they are of being injured by a small amount of radiation. Astronaut (talk) 18:15, 17 March 2011 (UTC)[reply]
At the moment, maybe yes. But the situation is fluid, and if shit goes bad, which it can very quickly, it can go very bad. Thousands and likely millions of people had measurable and sometimes drastic health outcomes from the Chernobyl disaster, and while right now things are not Chernobyl bad, people may not want to be around when it does. To get back to answering the first questions, the real reason is that there is something in the general human psyche that fears disaster and catastrophe, that is events where dramatic and large damage occurs in the very short term, but does not really fear small, incremental, or common dangers which only show their harm in the long term after many years. Thus, people really fear plane crashes, but car crashes aren't that scary, since plane crashes, though rarer, are more dramatic and catastrophic. And people fear being fat even less than getting in a car crash, even though being fat is going to kill many more people, and cause much more measurably bad health outcomes than car wrecks will, if only because not many people die or get hurt instantly from being fat. It's the same deal with nuclear power vs. coal power. What worries people is not nuclear waste (even though THAT is the real danger), what worries people is their local nuclear power plant blowing up like a bomb and killing all of them isntantly. Coal power, which has very little danger of blowing up and spreading instant death around the country side, feels safer because of that reason, even though we know that it is actually worse for our health, and for the health of the earth, than Nuclear. --Jayron32 18:42, 17 March 2011 (UTC)[reply]
I'm not sure why you think waste is "the real danger." It is a difficult technical problem only because we'd like to be able to say that it will be totally containable for thousands of years. In the short term, dry storage of waste is extremely safe, providing you don't live right next to it. (Wet storage is a different question, of course.) The political difficulties of waste siting are vastly overblown compared to the technical risks. (Which is not to say there aren't technical risks, but they are very minor. You can see this when you look at the actual engineering assessments of the hazards — it's things like, "will 100 people get cancer in the next 100 years" — not great, but hardly public enemy #1.) --Mr.98 (talk) 19:04, 17 March 2011 (UTC)[reply]
It's relative danger, again. In the long term, in accumulative effects, more problematic outcomes are likely to occur from nuclear waste than from power plants blowing up. Nuclear waste may be more safe than say, coal slag or greenhouse gas emissions from ordinary cars, but it is also probably the more problematic part of the nuclear equation picture, when compared to the dangers of catastrophic nuclear plant failure. But because it is cumulative and slow moving, it tends to get ignored. The point is not that nuclear waste is either perfectly safe, or the worst thing ever to have occured to humanity; people want to paint the world in dichotomies like that, much as you just charactized my arguement. Its that, taken in comparison, we can say that nuclear waste is more problematic than some stuff (like say, plant failure) but less so than other stuff (like, say, smoking cigarettes). --Jayron32 19:41, 17 March 2011 (UTC)[reply]
I think I read (a WP article?) about the over-reporting of train crashes (rare, kill more, overall death rate lower) and car crashes. Seems to be similar here. Can't find it now, though. Grandiose (me, talk, contribs) 18:53, 17 March 2011 (UTC)[reply]
The world needs energy, and all have environmental impact. You decide:
  • Oil: Greenhouse-gas pollutant, limited amount to drill safely, Deepwater Horizon and Exxon-Valdez.
  • Coal: Dirtiest greenhouse gases, over 20,000 miner instant deaths per year (most in China, fewer in US, but major long-term health impact), and more radioactive than nuclear waste.
  • Nuclear: only three major accidents in 60 years, extremely expensive start-up, but so far the only "wasteland" area is in Chernobyl - atmospheric radiation accidents disperse quickly.
  • Hydroelectricity has major ecosystem impact and is not universally available or unlimited, as with renewables like solar, wind, and wave.
So indeed, take your pick. SamuelRiv (talk) 19:32, 17 March 2011 (UTC)[reply]
I disagree about the nuclear waste impact you've given, as we are still experiencing effects in the UK, hundreds of miles from Chernobyl: Chernobyl_disaster_effects#24_years_after_the_catastrophe. I also notice you refrain from mentioning the environmental impacts of renewable energy. --TammyMoet (talk) 21:27, 17 March 2011 (UTC)[reply]
I don't see that data on coal miner instant deaths in the article cited. Yes, it's dangerous, both in the ground and downwind, but would it be if we spent the kind of money we spend making nuclear plants "safe"? Wnt (talk) 23:41, 17 March 2011 (UTC)[reply]
If you spent that kind of money on coal, it would no longer be cost effective. Nuclear energy is far more cost effective, to start, allowing you to add lots of safety precautions and still have it be competitive. StuRat (talk) 00:23, 18 March 2011 (UTC)[reply]
I have never seen an economic justification for nuclear that includes the real cost to future generations of managing the waste. HiLo48 (talk) 07:06, 18 March 2011 (UTC)[reply]
Well, then, you'd have to compare that with the real cost to future generations of the alternatives. In the case of fossil fuels, that would include moving the populations of major cities on the oceans inland some 50 miles to deal with rising sea levels from global warming, or building massive dikes around them. I think that's several trillion dollars right there. Then there's the increased damage from hurricanes and tornadoes to consider. StuRat (talk) 07:31, 18 March 2011 (UTC)[reply]
The 'real cost to future generations' is usually negligible. Assuming an annual real rate of return of 7% (a conservative 10% growth, less 3% inflation) a dollar paid in 2050 is worth about seven cents today. A dollar in 2100 is worth about a fifth of a cent today. A dollar in the year 2500 is worth a bit less than a billionth of a cent. If one honestly figures the cost of processing and safely storing the waste for the next fifty or sixty years, then the real cost to store it forever is only trivially greater. TenOfAllTrades(talk) 13:55, 18 March 2011 (UTC)[reply]
I disagree. Yes, each dollar spent in 2050 will be worth less, but presumably more dollars will need to be spent in 2050 for the same activity as today. If the inflation rate of minding nuclear waste is the same as the general inflation rate, then they should cancel out. The only reason I could see why it would have a lower inflation rate is if electronics to detect radiation levels become relatively cheaper. While the cost of electronics does tend to fall relative to other items with time, radiation detectors may be an exception, since too much miniaturization (the primary driver of cost savings) may cause them to fail when exposed to radiation. As for your 10% annual economic growth rate, that's absurdly high, except maybe in China, but even there it's unsustainable in the long term. Perhaps you meant the 10% to be the returns from investing money now, say in the stock market, to cover later costs ? That logic would only apply if such investments were actually being made, and, even then, one would need to consider the opportunity cost versus investing that money elsewhere. StuRat (talk) 18:47, 18 March 2011 (UTC)[reply]
I'm not sure you understand how future costs are evaluated (and discounted) for the purposes of making comparisons between expenditures that occur in the future versus those which take place immediately. As to whether or not such investments are being made, for the United States, at least, the Nuclear Waste Policy Act requires utilities to contribute to the Nuclear Waste Fund; the Fund currently has about $25 billion in assets. TenOfAllTrades(talk) 19:25, 18 March 2011 (UTC)[reply]
And is it currently invested in a financial instrument earning a conservative 10% growth per year ? StuRat (talk) 19:29, 18 March 2011 (UTC)[reply]
The data regarding yearly international coal miner deaths is taken from the "China" section. Official China Labor Bulletin statistics cite 6000 deaths per year, and the number is adjusted to reflect the vast number of mines with few or no records (particularly those of accidental deaths). Additionally, I get sources for 400 deaths/yr in the US from black lung disease, which of course is an immediately-identifiable etiology (as opposed to cancer). I don't mention environmental impact of renewables, just that they can't be tapped wherever and whenever you want and thus will not replace all power, but you're right that like anything else they have environmental impact as well. Regarding long-term Chernobyl effects outside of the immediate area, fair enough. I will note, though, with respect to the compare-two-evils fallacy, that the amount of atmospheric fallout from Chernobyl is negligible to that of the above-ground nuclear tests. Regarding investment, in the US where coal is king we invest heavily in safety, which is why miner deaths per year has gone from thousands 50 years ago to 30 today. SamuelRiv (talk) 00:45, 18 March 2011 (UTC)[reply]
I am skeptical that China really has ~13000 deaths a year from coal mining that they don't know about; [8] sounds like a confident source. Obviously 6000 deaths is already intolerable, and perhaps the question of nuclear power in China might go a different way. Then again, Nuclear power in the People's Republic of China is only 1% currently, and who knows how it will work out for them (especially in the same poor regions of the country)? Wnt (talk) 01:51, 18 March 2011 (UTC)[reply]
The answer to the OP's question is quite simple. People display irrational behavior because people are irrational. Does that really surprise anybody? Dauto (talk) 23:57, 17 March 2011 (UTC)[reply]
Displaying an irrational fear takes a lot less effort than learning the science so that you can display a rational fear. HiLo48 (talk) 00:04, 18 March 2011 (UTC)[reply]
That's just a tautology. It fails to explain why the nuclear fears touch off such irrationality in particular. --Mr.98 (talk) 02:08, 18 March 2011 (UTC)[reply]
My point is that people in general are irrational just about all the time, so it is not surprising that they are also irrational about that particular subject. Dauto (talk) 12:55, 18 March 2011 (UTC)[reply]
Some thoughts as to why nuclear power feeds irrational fears:
1) Radiation is invisible. Thus, people don't believe when politicians and "experts" tell them everything is safe. If radiation was visible, they would know if an area was safe or not. Perhaps if everyone had Geiger counters, they would feel safer, both because they would know if radiation levels went up, and would realize that there's background radiation everywhere, and it's nothing to worry about. Maybe portable pollution detectors would also be a good idea, so they would know when they are in an areas of (fossil fuel) air pollution, and would see how much worse that problem is.
2) Nuclear waste is concentrated, versus fossil fuel pollution, which is widely distributed. It's easier to point to a barrel of nuclear waste and think "that's dangerous" than to point at the sky and think "that's dangerous". If, at some point, fossil fuel pollution is also concentrated into barrels of toxic waste, then this difference may disappear, when people compare millions of barrels of FF waste with a few of nuclear waste. StuRat (talk) 00:32, 18 March 2011 (UTC)[reply]

I think of several things:

  • Nuclear power is very expensive if you calculate the absolute cost. Reprocessing is extremely expensive. Storage for 10000 years is also very expensive. It only works when the military and the government pays for the expenses.
  • I like to imagine a conflict like that in Libya in a country with a lot of nuclear power plants. All people leave and one after the other explodes. Or in like in Yugoslavia. When one party shells the nuclear power plant instead of a bridge. Or like in Egypt. When after an election a fundamentalist government Israel bombs the power plants as a friendly first gesture.--Stone (talk) 08:15, 18 March 2011 (UTC)[reply]
Bombing a neighbor's nuclear plants isn't a good strategy, as the radiation would be likely to spread back to you, and also piss off other neighbors. Terrorists, on the other hand, might not care if they poison everyone, although PR is still a concern, even for them. I have always been an advocate of building nuclear plants more safely, though, such as in old mines, far from population centers (the cooling towers can still be above ground, but the radioactive portions should be safely hidden). The nuclear waste can then be kept in the mine permanently, after the plant is decommissioned. This does require transporting the power further, with more losses, but this cost can be justified both by improving public safety and preventing the nuclear power industry from suffering these periodic black eyes which threaten to destroy it. In an age of terrorism, we have yet another reason. The distant, underground construction also gets by the NIMBY problem. StuRat (talk) 17:56, 18 March 2011 (UTC)[reply]
A recent (er, future...?) piece in the New Yorker ("The Nuclear Risk," March 28 2011) also discusses the general issue of risk assessment of nuclear energy, concluding: "As the disaster in Japan illustrates, so starkly and so tragically, people have a hard time planning for events that they don’t want to imagine happening. But these are precisely the events that must be taken into account in a realistic assessment of risk. We’ve more or less pretended that our nuclear plants are safe, and so far we have got away with it. The Japanese have not." WikiDao 17:13, 18 March 2011 (UTC)[reply]

Elastic - is it okay to keep it stretched?

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I need to know how bad it is for elastic to be kept it in its stretched state for a very extended period of time. Thanks. 71.220.225.153 (talk) 19:49, 17 March 2011 (UTC)[reply]

I'm not sure if that would effect how long it will last, as, for many elastomers, "aging" is due to mainly exposure to UV light or evaporation of volatile components. However, one concern is that when it does finally give way, it may injure somebody, say by snapping them in the eye or dropping whatever it was holding. Can you tell us what you had in mind as far as the type of elastic and load ? StuRat (talk) 00:09, 18 March 2011 (UTC)[reply]
I recently bought a bandoleer to hold a bunch of shotgun shells. The holders for the shell are made out of elastic and I was going to store the bandoleer with shells loaded in it unless it would wear out the elastic and make it unusable. As of right now I'd say the elastic is far too tight. It is fairly difficult to get shells in and out of it. 71.220.225.153 (talk) 05:43, 18 March 2011 (UTC)[reply]
Well, then you want to stretch the elastic, right ? I think that might work. However, certain types of elastic might also leave residue on the shotgun shells, as the elastic deteriorates, and this could interfere with performance when the shells are used. A safer approach might be to remove the shells, and replace them with something as large or larger, like rolled up newspaper bits, to do the stretching. A similar method is often used to help shoes in storage keep their shape. StuRat (talk) 07:22, 18 March 2011 (UTC)[reply]

Virgil C. Summer

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who was Virgil C. Summer? a nuclear plant is named after him?? — Preceding unsigned comment added by Timc321 (talkcontribs) 20:01, 17 March 2011 (UTC)[reply]

He was a president of the South Carolina Electric and Gas Company, see [9] for a very brief statement as such. Since they built and own said nuclear plant, it makes sense they would name it after a former president of the company. --Jayron32 20:16, 17 March 2011 (UTC)[reply]
And this Google Books search turns up a few more scanty refs: [10]. --Jayron32 20:19, 17 March 2011 (UTC)[reply]
I've added a reference (from SCANA's own website) to that effect to the Virgil C. Summer Nuclear Generating Station article. Unfortunately there's no more worthwhile info, beyond what Jayron32 has found already, there. -- Finlay McWalterTalk 20:27, 17 March 2011 (UTC)[reply]

High oxidation numbers: above 8?

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Is there any reason why transition metals' oxidation numbers always seem to cut out at eight (in group 8 elements)? For instance, why can't you get nine on a group 9 element (I'm thinking rhodium, iridium, possibly also americium where the d electrons are replaced with f) to make it d0? Like say iridium(IX) hydride (IrH9), which is isoelectronic with the real complex ReH92–. Or I could certainly imagine a hyper-periridate anion IrO5. Os(VIII) forms readily and it's nearly identical. (Feel free to get really in-depth; I'm three years into a chemistry masters degree.) 137.205.222.209 (talk) 20:40, 17 March 2011 (UTC)[reply]

Might if have to do with the geometry of 9-ligand complexes? Once you get over 6 ligands, the Octahedral molecular geometry, things get weird. There are occasional higher order bonding schemes, like Pentagonal bipyramid molecular geometry but they are quite rare. You almost never find bare transition metal ions in solution or in crystal networks, especially with the higher oxidation number metals; even low-oxidantion number metals like copper-(I) and copper-(II) form complexes very regularly. Admitedly, my chemistry is a bit older than yours, since you are in it, and it's been 15 years or so for me since I studied this stuff in depth. There's probably some combination of electrostatics and orbital geometry that makes high oxidation number transition metals to be highly unlikely. The article Ligand field theory hints on some of the problems with considering what happens in d-orbitals; at first approximation, and under normal circumstances, all 5 d-orbitals are degenerate, which is true energetically, but in real bonding situations, the three d(xy), d(xz), and d(yz) operate differently than do the d(z2) and d(x2- y2) orbitals. Making a WAG, my guess is that due to these differences in d-orbital organization, there's some barrier towards, say, removing all 9 electrons from the 6s and 5d electrons in Iridium; in other words theres something in the way that the d-orbitals are organized that presents a large jump in ionization energy between the 8+ state and the 9+ state. f-electrons are so deep, I doubt they participate to any great end in hybridization, in bonding, or in ion formation in the way that s, p, and d orbitals can. Again, this is just me riffing on my admittedly underused 1990's era inorganic chemistry knowledge... --Jayron32 02:32, 18 March 2011 (UTC)[reply]
More than just that they "seem to cut out at eight" (emphasis mine), that is citedly the actual highest known (at least as of a little over a year ago), although there are groups studying that limit. See for example doi:10.1002/cphc.200900910. DMacks (talk) 03:05, 18 March 2011 (UTC)[reply]

Deliberate meltdown

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Lets say some psycho wants to create a doomsday device. What would happen if someone made a reactor that had no coolant, turned it on full power, and deliberately let it meltdown. Could this have global effects or would the effects be relatively localized near the point of meltdown? ScienceApe (talk) 20:41, 17 March 2011 (UTC)[reply]

Basically what you are describing is a type of dirty bomb. Looie496 (talk) 20:57, 17 March 2011 (UTC)[reply]
There are two hugely relevant variables. How large is the device, and where is it located. Googlemeister (talk) 20:58, 17 March 2011 (UTC)[reply]
A meltdown would certainly be no worse than a nuclear bomb with the same amount of material. The nuclear bombs used, either for wars (hiroshima) or for Nuclear weapons testing, do not appear to have had global effects. 83.134.176.57 (talk) 21:08, 17 March 2011 (UTC)[reply]
You really cannot compare reactor meltdowns and nuclear weapons. (What do you even mean by "the same amount of material" in such a comparison? Reactors use tons of fissionable materials; nuclear weapons use kilogram quantities.) The comparison is highly misleading in every way. They are very different types of events. The only similarity is that both involve distributions of fission products. And there is some dispute as to whether the years of atmospheric nuclear testing did have global effects (e.g. increased thyroid cancers, etc.). They certainly had national effects. But again, this is kind of irrelevant, because it tells you very little about meltdowns. --Mr.98 (talk) 21:28, 17 March 2011 (UTC)[reply]
This is essentially what happened at Chernobyl, albeit not "mad men" so much as "fools." The acute effects are "regional" — not global, but certainly not just "local". There are some "global" effects, but they are very hard to measure (statistical up-tick in cancers, for example — hard to figure out what the causes of those are). --Mr.98 (talk) 21:28, 17 March 2011 (UTC)[reply]
The cobalt bomb was proposed as a similar device; one could translate its principles into a reactor, but a bomb would be more effective at creating and distributing the fission products. I believe (the article doesn't mention it, but its references do) that one advantage of such a device would be that it would not have to be transported to the target and could be arbitrarily large, providing, of course, that the device is understood to be a "doomsday weapon." Acroterion (talk) 21:37, 17 March 2011 (UTC)[reply]
After encountering cobalt bomb, I ran across some unusual claims that the Russians had actually built a Doctor Strangelove type device. These emanate from Bruce G. Blair. I encourage anyone to take a look at the evidence and try to figure out if this is plausible or not; I've added a brief mention of what I found in the article. Wnt (talk) 00:28, 18 March 2011 (UTC)[reply]
He's referring to Perimetr, the so-called "Dead Hand" system. It's not really the same thing as the doomsday device. It was a command and control system that would allow the top Soviet leaders to say, "we're in a very tight time, and nuclear war could start any minute, so if you need to, launch the bombs." Then the Soviet army heads could, if they felt things were really bad, could say to a specific base, "look, if you lose contact with us, assume we're toast, and launch the nukes." Then the specific base would send up a special ICBM that had a radio transmitter on it that would say to all of the other ICBM bases, "go ahead and launch 'em, boys!" and then they'd all launch at the USA or whomever. So it's that last bit that makes it sound Strangelovian — it's a one-way trip at that point if a bomb goes off (or if for other reasons they lose contact). But it's a few more steps than that. The reason to make it was not some sort of MAD pact; it was due to the fact that in the 1970s the Soviet army realized their leaders were a bit dotty (Brezhnev and Chernenko being the obvious ones) and might not be able to order the nuke attack if it came down to it, and also they realized that a very weak point in the Soviet ICBM system was the communication system between individual missile bases. (For more information, I heavily recommend David Hoffman's The Dead Hand, which came out a year or so ago, and is pretty well-researched. --Mr.98 (talk) 01:28, 18 March 2011 (UTC)[reply]
Ach! I got hit by the oldest trick in the book that time. The first 'sources' I came across in the blogosphere made it sound like the system set off cobalt bombs automatically, but the ones closer to the source I actually cited didn't actually make that link, even though they talk about both things. (They're just both reminiscent of Doctor Strangelove. That one catches me more than any other. Wnt (talk) 01:41, 18 March 2011 (UTC)[reply]
I've run across references (don't ask me where, it's been a while) to a similar last-ditch American system, going by the codename Last Dance. Acroterion (talk) 02:09, 18 March 2011 (UTC)[reply]
Just a pointer - I once read an article on history of nuclear wepons. According to it at first the concept existed, but no one was sure how it should look like, so some developed concepts similar to nuclear reactors (it seems everyone might have used reactors to explore the process, but I think it said that Nazis at least wanted to make an acctual bomb that way) ~~Xil (talk) 10:36, 18 March 2011 (UTC)[reply]
It's true that the initial conception of a nuclear bomb by Heisenberg was something in between a reactor and a bomb. But it was very ill-conceived, and was reflective of the fact that they didn't realize they could do a fast-neutron chain reaction. There is a lot on this in Heisenberg and the Nazi atomic bomb project by Paul Lawrence Rose (he calls it the "reactor-bomb" if you want to skim through the Google Books edition). --Mr.98 (talk) 12:54, 18 March 2011 (UTC)[reply]