On cooling the Japan nuclear reactors?

Because water is the best and safest way to cool them. This is not like putting out a campfire.

1. Liquid nitrogen in large quantities is not that easily obtained.

2. Liquid nitrogen would likely rupture the containment vessels.

3. Liquid nitrogen would evaporate too quickly to be useful.

4. The systems are designed for water cooling. Unfortunately, they had to use corrosive sea water at first but now almost all the water is fresh water.

And finally, the situation is really under control (the media hype is not). Every day has shown progress. Consider that forty year old plants were hit with an earthquake five times the strength they were designed for and yet they still shut down safely. The generators came on like they were supposed to when grid power was cut. Then the tsunami hit and the generators were wiped out. However, the battery backup still worked for the designed eight hours. The problem happened when no new generators could be put in. Even so the problems have been minimal--media scare mongering for ratings not withstanding.

Here is an informative article describing the situation:

http://bravenewclimate.com/2011/03/13/fukushima-si...

And here is where you find current, factual status information:

http://www.iaea.org/newscenter/news/tsunamiupdate0...

And here is a chart that helps make sense of the numbers:

http://www.xkcd.com/radiation/

I think you are.

If they were to pump these agents into the reactors, they would evaporate so quickly that it would not stabilize the reactors but react in the form of explosion which could spread radioactive materials up in the air resulting in tons of possible fallout particles onto everywhere even on your country.

In this Fukushima case, quick freezing will not make a big difference because the fuel rods in the reactors will keep providing heat for a long term.

Under these circumstances, most needed is long term and constant cooling and it can only be achieved by sea water at this point of time and hopefuly it is replaced with water shortly which can not be provided due to malfunction of machinery for water circulation devastated by the tsunamis.

No I don't think you are.

In fact you reminded me I was watching the events with my partner (last weekend) and said I thought they should already be building a wall around the whole site to provide a dam to flood it.

At one point I now remember saying or see if they could get liquid Nitrogen into the area.

Nitrogen I suspect would be a good option as it is inert, however the problem may be safety and getting large enough quantities to the heat source.

And the large amounts of water now pumped in may cause their own problems.

However I think you have a good idea.

you're able to desire a river of water to circulate into each and each or the reactors and save on flowing for weeks till the reactors have cooled down, then there is the question of environmental injury through fact the water will leak out into the ambience.

They are pumping a combination of saltwater and boric acid to cool the reactor rods. Boric acid acts as neutron poison, absorbing low-energy neutrons, thereby reducing likelihood of fission reactions occurring.