s***x
发帖数: 638 | 1 还好吧
This table of nuclides shows the 905 observed nuclides that are either
stable, or (if radioactive), have half-lives longer than one hour.
At least 3,000 nuclides have been experimentally characterized |
|
l****e
发帖数: 137 | 2 the limit for radiation level is usually set at 2.5 uSv/hr or 0.25 merm/hr.
even 0.1% of the leak is long-lived
nuclides, it is a threat. by the way one of the most volatile radioactive
nuclides in the reactor is I-129 with a
half-live of 15.7 million yrs. ofcoz, it maybe not the major contribution.
life |
|
G*******g
发帖数: 556 | 3 so among the 0.1% extra dose, the contribution from I-129 is very limited,
though it will last through the end. The main body that makes the 0.1% extra
dose, right now, is Cs-137 and Sr-90. Ok, I see the difference, you are
talking about the 0.1% extra dose after hundreds of years, I am talking
about the 0.1% extra dose immediately after a nuclear accident. Yes, after
hundres of years, if 0.1% extra dose is measured, it will remain ~0.1% for a
long long time.
the limit for radiation level is us... 阅读全帖 |
|
x****u
发帖数: 44466 | 4 文章里面说得很清楚：
decay是指highly radioactive fission products，也就是U什么的分裂之后生成的核
素。
Principles
In a nuclear reactor, the fission of heavy atoms such as isotopes of uranium
and plutonium results in the formation of highly radioactive fission
products. These fission products radioactively decay at a rate determined by
the amount and the type of radioactive nuclides present. Some radioactive
atoms will decay while the reactor is operating and the energy released by
their decay will be removed from the core al... 阅读全帖 |
|
g**1
发帖数: 10330 | 5 NEWS ADVISORY: Nuke agency expresses 'strong regret' over erroneous
nuclide analysis
NEWS ADVISORY: Groundwater highly likely polluted with radiation despite
TEPCO error 11:58 1 April
NEWS ADVISORY: Part of TEPCO data on groundwater, trench contamination had
error: agency |
|
l****e
发帖数: 137 | 6 you mistaken the concept of item number, activity and radiation dose.
i guess u r thinking, oh, there is radiation leak, it leaks xxx item number
of radioactive nuclides, then oh, the
half-lifetime is very long, so the activity must be very low, so the dose is
low.
In reality, whenever there is radioactive leak, it is measured either by
activity or radiation dose, which means
if the significant components of the leak are long lived and the initial
activity or dose is high, the threat stays
very ... 阅读全帖 |
|
G*******g
发帖数: 556 | 7 Yes, the radiation will last long, but I am talking about its impact on
human health. I am not talking about dose here, but the dose RATE, which is
different from dose itself. It represent to a very large extend the actual
damage a radiation will do to human body. The damage that radiation can do
to a human body depends on the accumulative does, but more significantly on
dose rate, that is the dose that you receive per second. The activity can be
low, but the pollution duration can be long, they... 阅读全帖 |
|
l**********n
发帖数: 8443 | 8 atom is based on electron. electron是个神器。nuclide is based on atom. |
|
