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Seriously? Go to Wikipedia and search for "uranium". Since that seems too difficult for you here's a link and a quote.
https://en.wikipedia.org/wiki/...

An additional 4.6 billion tonnes of uranium are estimated to be in sea water (Japanese scientists in the 1980s showed that extraction of uranium from sea water using ion exchangers was technically feasible).

And don't just reply with, "Wikipedia is not a valid source!" Follow the citations on the Wikipedia page and you'll find this:
http://www.jaea.go.jp/jaeri/en...

I'm sure that there are better sources out there but you can type into Google just as easily as I can.

I would agree that the regulatory environment in the west is hell-bent on killing any and all new projects, but you really can't blame them for being super-duper careful, as they have a hysterical public to deal with who perceive any failure, however small, as a catastrophe, thanks in large part due to media hype and fear mongering by news outlets and environmental groups. In Russia and China, meanwhile, the public realize that realistically it's either nuclear, with its occasional potential radiation release when it goes wrong (which can kill people, no doubt about it) vs. coal and natural gas, which kill people even when operating right and make places like Beijing look like freakin' Silent Hill.

As for IFR, no, the fuel isn't molten in the core, they're still solid fuel rods. The important difference for IFR fuel is that it's a pure metal, not an oxide, so its heat conductivity is much higher, which in turn allows higher temperature operation without stressing the material so much (as internal temperatures are far lower than the 1000C gradient experienced in oxide fuels). From this design decision, tons of other important features are derived, like the very strong negative temperature reactivity coefficient, the passive heat removal, ease of reprocessing (no more acid processes), etc. It's really quite an elegant design and it's ready to roll today.

A report EFDA in preparation for ITER here. It gives shot cycle times:

• Jet: 30 minutes
• DIII-D: 14 minutes
• ASDEX: Just under 30 minutes
• FTU: 20 minutes
• RFX: 10 minutes

It even discusses replacement schedule of some equipment for ITER, with only a few blanket modules replaced per year and a complete replacement only every 10 years, for example. The time between shots is referenced as 1600 seconds here due to the limitations it places on computing requirements (so repetition rate would be ~2000 seconds since the plasma shots will be up to 400 seconds).

The introduction in the full text of the paper here discusses how HiPER will be designed with a target of 10 Hz repetition rate for a 100 full power shot sequence.

The report here mentions how the Omega laser system is designed around a 30 minute repetition rate.

3 minutes for LHD

15 minutes for NSTX

2 minutes for MST

5-15 minutes for TFTR

20-30 per working day for JT-60

Even the ones I references as being kind of slow, NIF and Z-machine, are one shot per day, not weeks and months between shots.

The smaller projects I've worked on typically ran every 2-5 minutes when cycling during a normal day, limited by them typically using underpowered, but free (due to inheriting from previous experiment) cooling system. Their run campaigns were limited by staffing, as when the handful of people were busy analyzing data, no one was left to run the machine. Larger machines I've worked on had technicians and large teams to run 5+ shifts a week, and would run for at least a third of the year. Time not running was typically spent calibrating, repairing, upgrading diagnostics, and occasionally power supplies, most of which are components a production reactor would not have. Larger machines had a much more diverse diagnostic suite, so were much harder to organize and get things ready for a full run campaign, for reasons unrelated to plasma or neutron damage. The larger machines also could run into budget reasons running for a larger part of year due to staffing (technicians assigned to more than one thing) and power costs.

Neutron damage, failures due to plasma damage, and over all maintenance costs and cycling are a MAJOR issue that fusion research needs to address before becoming commercial. But that still doesn't mean your "hours, days, and even weeks" accurate for anything currently or in the near future.

It'll be interesting to see if Gen 3+ and Gen 4 nuclear reactors will be allowed longer terms of lease, given that they have less parts to fail and more passive saftey systems. I think that nuclear could really be a keystone of Japan's nuclear energy future. That, and the Japanese have done research on how to extract uranium from the sea after Uranium prices spike in the future once easily mineable resources become exhausted. If we don't get breeders or thorium running, Japan has done the research.

http://www.jaea.go.jp/jaeri/english/ff/ff43/topics.html

Japan's only major energy resource is the sea. And the sea has enough Uranium to keep Japan ticking long after their population dwindles away due to their low birth rate.

Here are some total cross sections for lead isotopes: http://wwwndc.jaea.go.jp/nd2001/proc/pdf/1_0327.pdf Around 11 barns so scattering is much more frequent than absorption I think.

If Wikileaks had an article posted about "How to refine uranium with sea water, bottle of bleach, and a house hold blender" then I would be concerned.

Interesting mention considering that obtaining uranium from seawater is quite possible and in fact Japan is developing capacity to do so so they don't have to rely on imported uranium to fuel their reactors. http://jolisfukyu.tokai-sc.jaea.go.jp/fukyu/mirai-en/2006/4_5.html

OK - fine. How many parts per million of uranium is there in sea water, eh? Now, take the number of parts of Uranium you will need to run a reactor. Multiple those two numbers, and you will get the volume of water you will need to boil off to get the uranium you need for ONE reactor.

About 3 parts per billion

That's the first I've ever heard about anybody being crazy enough to try to boil off the water to extract the uranium.

http://jolisfukyu.tokai-sc.jaea.go.jp/fukyu/mirai-en/4_5.html

If 2g-U/kg-adsorbent is submerged for 60 days at a time and used 6 times, the uranium cost is calculated to be 88,000 yen/kg-U, including the cost of adsorbent production, uranium collection, and uranium purification. When 6g-U/kg-adsorbent and 20 repetitions or more becomes possible, the uranium cost reduces to 15,000 yen. This price level is equivalent to that of the highest cost of the minable uranium. The lowest cost attainable now is 25,000 yen with 4g-U/kg-adsorbent used in the sea area of Okinawa, with 18 repetitionuses. In this case, the initial investment to collect the uranium from seawater is 107.7 billion yen, which is 1/3 of the construction cost of a one million-kilowatt class nuclear power plant

So, of the order of $1bn to setup and then around 250$/kg to extract using current technology to extract enough uranium to run 6 nuclear power stations.

Tim.