Chriogenical Freezing (dont know about spelling)

[M-CaTZ]

I just wanted to hear everyone's thoughts on the subject.

If anyone knows what the current usage is, and what is the risk factor in using it. Also, I know there have been many rumors of people being frozen, but i was wondering what is the longest someone has been frozen, and are there any people right now, who are frozen, inorder to preserve their lives, and want to wake up in a few years

[fafalone]

People frozen now were dead or very near death, wanting to be unfrozen when a cure is possible. Currently we do not have a technique that allows us to bring frozen humans back to life, although we can do it with several species of frogs.

[Miseria_]

I thought It was imposible with humans due to the amount of water held in our cells. Don't all of our cells get forced apart and damaged due to the expanding structure?

 

I may be wrong, please take no offence.

[fafalone]

That's the challenge, preventing the crystallization of water. It's not impossibly by theory, just not currently acheived.

[Radical Edward]

I heard that it was done with a hamster.

[Miseria_]

Thanks Ed, I now have the Idea of exploding hamsters stuck in my head.

 

That and the common equation of {Microwaves + Hamster = bang}

[M-CaTZ]

Faf, what is the theory that says you can prevent the crystalization of water in the human body. It seems impossible, but if you have a link or something that I can go to, which explains it, post it please

[Radical Edward]

Originally posted by M-CaTZ

Faf, what is the theory that says you can prevent the crystalization of water in the human body. It seems impossible, but if you have a link or something that I can go to, which explains it, post it please

 

there isn't a specific theory per se, it is just that we can generate supercool fluids, and by flash freezing, should stop the crystallisation process from occuring. you can see the rate of freezing by the crystal size in certain rocs; stuff that has frozen very rapidly has a glassy look, wheras slow cooling rocks have had much more time to crystallise.

[Giles]

Originally posted by Radical Edward

I heard that it was done with a hamster.

It was that or flush it.

[james123]

i was watching a special on cryogenic freezing and such and

i heard that for those people before they are frozen there injected with a anti-freeze type of fluid that would prevent the water in the cells and such from actually freezing. Another one of the methods i've heard about was "blast freezing" well, sumthing like that because its been known that when a human being is suddenly in extremely cold water the heart rate drops rapidly and then beats really slowly sorta like a state of suspened animation.

[VendingMenace]

I thought It was imposible with humans due to the amount of water held in our cells. Don't all of our cells get forced apart and damaged due to the expanding structure?

 

 

THe problem is not really with the expansion of the water upon freezing, but with the formation of crystals. The water crystals that are normally formed durring the freezing process are quite sharp, and will puncture the cells. The problem with unfreezing (some call it thawing ) is that you would find yourself with every single cell in your body perforated -- generally not recomended.

 

Anyways, as has been aluded to in other posts, the trick is then to freeze someone while not allowing these crystals to form. Unfortunately, the only ways we know of doing this (adding chemicals or the super-cooled route) would kill someone before they were frozen. And with the chemicals approach, you would also have toxic levels of the chemicals within your system when you woke.

 

those seem to be the problems that we need to overcome at the present. There may be others, but we cannot consider them until we solve these ones first.

[aman]

I watched a special on PBS yesterday about water and the hydrologist mentioned water occurs in seven different states but did not elaborate. I know of gas, liquid, and crystal ice. Are there any others I don't know about? Maybe one of those other states would allow freezing with no damage.

Just aman

[Skye]

I could be wrong because this is just from memory from a lecture.

 

The others are different crystal arrangements for ice at really high pressure. Basically it packs the molecules into a smaller volume, which doesn't happen at lower pressures because of the repulsive hydrostatic charges.

 

This seems to be along the same lines:

http://www.betterhumans.com/Errors/index.aspx?aspxerrorpath=/searchEngineLink.article.2002-08-24-1.aspx

[VendingMenace]

Yes, exactly. There are several different crystal configurations of ice. Thus, they are sometimes reffered to as different states. Thought i think this terminology is somwhat confusing. Really they mean different phases, becuase going from one lattice to another in the ice involves the same equations as for the phase transition from liquid to gas.

 

And yes, some of these state could, in theory, be used, as they don't have jagged edges. The problem again is how to get the right conditions for these states without killing the person that you are trying to freeze.

[YT2095]

I wouldn`t have thought that sharp edges wouldn`t be so much of an issue given at water expands 11% on freezing anyway. surely it would still rupture the cell wall as it does with frozen pipes or milk bottles, the net effect is that same?

and an anti-freeze that replaced ALL the water (it would have to) is surely going to be toxic, if not almost impossible to flush completely away?

[VendingMenace]

Apperently the expansion is not really a problem (i would have thought it would be too). We used to freeze cells all the time in a lab that i worked in, and we could bring them back -- provided we took steps to prevent the shap edges buisness. We used a chemical (i can't remeber exactly what right now...bad memory) to prevent this. It just so happens that the cells we were using were fairly robust, so they could handle the toxity of this chemical upon thawing.

 

Of course, i am not a cryogenisist, but as i understand it, it is the sharpness of hte water that cuases problems.

[YT2095]

I realise it must be possible for simple organisms like in IVF and Embrionic freezing, but I still can`t get my head round the expansion thing? ok sure a zygote or a gamete would take micro seconds to freeze, but why doesn`t it rupture? or at least go soggy and flacid like some veg do if you don`t blanch them before freezing?

[aman]

There's a big difference in freezing rigid plant cell walls and expandable animal cell walls. Forensic pathologists have been fooled in the past about time of death if a body is frozen for a period of time. This is because there is very little apparent physical damage as long as there is no freezer burn.

Just aman

[Glider]

Normal ice expands 11% on freezing. The other forms of ice (Ice I, ice II and so-on) expand less as they are formed under pressure. Ice formed under the pressure of several bar is denser than its liquid state, and sinks.

[YT2095]

Hmmm.. Interesting!

is there anyway I could try this at home without blowing something up? ie/ pressure vessels, 12 gram CO2 canisters?

 

I gather you fill it with water, seal it, freeze it, and hope it doesn`t blow the door off or your hand when you re-open it

[Skye]

Presumably if you were fairly deep under water it would form. Maybe scuba down deep with a bottle of liquid nitrogen and open it up.

[YT2095]

aha! yeah, now that interesting!

I watched something similar to that on a Discovery chan, I was about methan gas fusing with water at very low tems and under exteme presure, it looked a bit like snow that burns! wierd stuff!

[VendingMenace]

aight, here is some more information. I've included a phase diagram in this post (though it has pressure on the x and temp on hte Y -- i hate reading them this way!) for the liquid and solid phases of water. As of right now, i believe there are 11 different phases of ice. The one that we see on an everyday basis is ice 1, though in this diagram it is ice 1h. So here is the diagram...

 

 

some cool things about this are...

1) THere are tons of phases, lots of em.

2) SOme of hte phases give ice a stable form even when the temp is above 0 degrees C.

3) ONe of the phases (VII) is stable well above 100 degrees C, normal bioling temp! wild.

 

Anyways, just thought i would share that with you, so if you wanted to try to make some phases at home, you would at least know what you would need .

 

(ps. if you are interested, this image came from this article. In addition to the phase diagram, it also has some graphics of the cristyline structure for these phases.)

[YT2095]

VM (hope you don`t mind the short version?),

the diagram didn`t display on my pooter sorry

 

the Ice phase VII at 100c!?!?! wowzers!

I`de like to see some of that or even try make some, I personaly cannot see how it`s even possible tbh, I was aware of 3 stages for water 4 If you count superheated water (not boiling but over 100C).

 

begs tyhe question what something like that ice VII would actualy look and feel like, It certainly couldn`t be COLD

Hmmm... certain Practical aplications spring to mind too!

 

do you have the URL`s that you looked at please?

 

all the best

[VendingMenace]

Ah, guess i should've checked out the links and stuff before i took off, oh well, guess that is what i get for being lazy

 

cool here is the link;

http://www.cmmp.ucl.ac.uk/people/finney/soi.html

 

the diagram that i tried to attach is also from this site.

 

If you want more information you could try googleing

 

phase diagrams for water

 

phase transitions for water

 

those should give you some stuff to look at. fun reading