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Comment Re:Not good for farming, but perfect for gardening (Score 1) 95

What you are referring to is the "effective half life" which is calculated using the radioactive half life (the one everyone is familiar with) and the biological half life (how long it takes your body to excrete half of the material). Let's take cesium-137 for example, its radioactive half life is 30 years and 29 days. The biological half life is 70 days. In this case, the half lives are so different that the radioactive half life doesn't come into play at all and the effective half life is 70 days.

Iodine-131 has a radioactive half life of 8 days 36 minutes, but is absorbed into the body more easily (thyroid) so its biological half life is 138 days. The effective half life becomes 7 days 14 hours

These figures are from WolframAlpha, and it has this data on many many isotopes.

Comment Re:Aside from hype, Apple's real policy... (Score 1) 601

Upstate New York, 25 years old and I know about it too (my father has done it many times). It makes sense because it is difficult for a long truck to see how much room they have between the back of their cargo and your car and you are too far back for them to be able to see any hand motions you might make. So it's just a courteous way to let them know that they have enough space.

Comment Re:Misleading Title As Usual (Score 1) 172

Yes, but without the tsunami the diesel generators would have been working.....that is the point. For the meltdown to have occurred solely because of the earthquake would have meant it had to melt before the tsunami hit. TEPCO is saying the meltdown occurred around 16 hours after the earthquake.

Comment Misleading Title As Usual (Score 3, Informative) 172

Nowhere in TFA does it say that the earthquake caused the damage to the reactor that led to it melting. Also, I doubt it is even possible for it to melt in the 40 - 50 minutes it took for the tsunami to arrive. It first has to evaporate or otherwise evacuate the water inside the reactor, and then heat up to about 2800 C to melt. What the article is saying is that the rods had melted much sooner than initially thought. The timeline changed, not the reason. They are also looking into possible complications that may have occurred in the initial hour (there is another report that the cooling systems were manually shut off after a pressure drop, as per the instructions for such a scenario), but nowhere does it suggest that the earthquake, and not the tsunami, caused the crisis. The closest it comes to that is saying that the earthquake may have "damaged" the reactor, but gives no speculation on the effect that it would have had on the cooling system. A crack in the containment vessel without any cracks in the reactor pressure vessel would not have been an issue.

Comment Potentially Good (Score 1) 374

The basic premise of this idea is not a bad one. Japan already has a similar mechanism in place for earthquakes. All Japanese-made cell phones are embedded with an alarm that is triggered by the early earthquake warning system (It only sets off the alarm for the people in the area expected to be affected). However, I think the reason it works is because it has a distinct alarm noise that is built in, not able to be disabled (even in silent mode), and there is no text to read. It helps give people a few moments to prepare or get to cove because they know immediately what it means. In those cases, quick conveyance of messages is key, as pointed out. Getting a text on a tiny screen is very useless for people with impaired vision or people who are driving. Perhaps a better solution would be to have the alarm indicate that they should quickly listen to their nearest source of the emergency broadcast system (radio, television, internet). The information is still passed on more quickly than before, but with much less risk, and much less annoyance if people don't care or are unable to read the messages they receive. That being said, Congress needs to carefully think about what messages are worth triggering the alarm for, or people will simply look for ways to disable it once they get too many messages that are not important. The Japan example is easy, earthquakes are universally feared and an early warning is highly desired. A message about the change of our terror alert might not be as welcomed.

Comment Re:Persective indeed (Score 1) 370

Oh, I didn't mean that it was my concern because it was dangerous, I just meant that it is waste that needs to be stored, and sooner or later we will run out of space to put it. Right? This issue will need to be addressed eventually, either through an advance in recycling technology or a way to generate the same amount of energy on less fuel.

Comment Re:Japan to raise severity level of Fukushima acci (Score 1) 370

I also arrived at the similar ~11PBq (11007.5 Tbq). I will take your next statement a step further with a rough mathematical approximation. This will be based on things that can be disputed, of course, but it's just for ballpark sake. The wikipedia article states that cesium-137 was being measured. According to, cesium-137 has a yield of 6.1%, and iodine-131 a yield of 2.8%. From that we can say that masswise, just under half (45%) of the amount of iodine-131 was released as cesium-137. WolframAlpha says that cesium-137 has a radioactivity of 3.214 TBq per gram. That comes out to about 3424.86 grams from the 11007.5 TBq. The calculated release of iodine-131 would come to 1572.07 grams of iodine-131. Iodine-131 has a radioactivity of 4598.8 TBq per gram. This would indicate that the released Bq would have been about 7229621.19 TBq, or 7.23 EBq. Of course, since iodine has a short half life, it is not a concern in the long-term.

This is of course, assuming everyone goes exactly to model so it is not terribly reliable, but you can get a rough idea. It is also based on my hilariously bad understanding of math, so if I'm out of my element feel free to correct me.

Comment Re:Persective (Score 1) 370

I agree coal and oil are not a valid solution, but I'm not convinced that nuclear fission is either. Accidents are not my primary concern though, it's the waste that bothers me. Hopefully this accident will bring some revived thinking to either how to improve the nuclear process (or at least start replacing such old technology like in Fukushima) or a viable renewable solution.

Comment Re:"May be" "Possibly" "Calm down" "Sleep" (Score 1) 280

Not to mention that the "allowed level" they are basing it on is not relevant in this type of situation. They are basing it off of the standards for drinking water absent any nuclear leak (i.e. drinking water that you would be drinking for your entire life) and as such, the limit is about 0.1 becquerels per liter (incredibly small). You can see this information in question 3 of this Q&A

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