How do cryo-vac packs work?
90750
when you break the seal you mix two chemicals that mix and react together in an endothermic reaction(one that absorbs heat). So heat is absorbed by the reaction and something else is cooled off.
693706
you will get more dust if the case is open.\n\ninside the case you will see a series of circuit boards with exposed silverish pieces all over them.  These pieces are taking on an electrical current, and thus have a magnetic charge.  Its this magnetic charge that will attract dust into the computer.  Opening the case will turn your computer into the equivalent of one of those "ionic air purifiers"... except it wont be any good at it.
667559
First off it isn't air in your can.  What you probably have is either propane or butane in the can.  It is a liquid under very high pressure.  However, when it loses its pressure, it expands rapidly, and for it to expand rapidly, it needs HEAT, so it pulls heat from its surroudings to expand.  The absence of heat is cold, so that is why the can freezes up.\n\nThe same principle works in an airconditioner.  The compressor, squeezes the freon gas so it becomes a liquid and gives up heat (outside unit called a condenser blows out hot air).  The liquid freon then travels to an expansion valve or capillary tube where the compressor that is squeezing the freon into liquid is also sucking gaseous freon in on the suction side.  So there is low pressure on the suction side.  The liquid freon from the expansion valve or capillary tube enters this low pressure area and expands rapidly.  As it does, it draws heat to expand, thus pulling the heat from your home and cooling the air.
139842
Place a lump of dry ice inside a chamber with some holes in the bottom that will fill with water, but has a sealed top. The water will flood into the chamber, and dry ice sinks in water. Properly weighted, the chamber will also sink to the bottom. However, as the dry ice warms up, it will sublimate to produce carbon dioxide. Some of the carbon dioxide gas will fill the top of the chamber with gas, which floats. Eventually, if the weights are balanced appropriately, the chamber will float back to the top.
1167328
sawdust act like a insulation and keep the ice cooler longer
1177407
Turn off the vacuum.\n\nremove tube from vacuum to flask.\n\nLift edge of filter paper.\n\nJust do something to break the vacuum.
893341
well if i am not wrong.. they work on the principle of thermionic emission... \n\nnow wat happens is ... at the cathode end ( negatively charged) there is a metal bit.. called emitter  and at the anode end( positive terminal) another metal called the receiver. the tube is vacuated and filled with gas, in this case a halogen vapour. \n\nwat happens is when a potential is applied, when we switch it on, the cathode emits electrons.\nthese electrons pass thru the vapours and ionise them. when ionised these gases emit energy in the form of light..\n\nthis is the explanation in the most condensed form... equations make it complicated for understanding... \n\nhope i did justice to ur query
192080
Is it within a vacuum?\n\nIf not, and if through your above given conditions resulted in air being compressed or what have you then I guess it would.
847700
i would try to find two sheets of a fine metal mesh. Use the first sheet to charge the incoming air and the second sheet as the negative attracting grid. place them about an inch from eachothers and attach the positive and negative terminals each to a sheet. I would use a car battery as this gives you the most voltage of something that is portable. Whatever source you get make sure it is dc and that each sheet of wire mesh is insulated from the other or else the electrostatic effect wont work. Or if you have ever seen the ionic breeze by sharper image it uses three or four metal plates placed side by side to achieve dust collection. This may work also.
793772
In cryopreservation, liquid nitrogen is used to preserve cells. Cells are usually stored in a 10% DMSO (dimethyl sulfoxide) and 90% Fetal Bovine Serum solution. They are transferred into cryo vials and stored in liquid nitrogen cryo tanks. Cells may be preserved at this state for many years.
933018
I've seen wound vacs work on some and not on others. it's hit and miss. the main complaint that i've received from pt's is that they can be very cumbersome.\n\ni wish the best
68984
I'm not sure (I actually like that answer up there), but here is a website with lots of stuff about Vacuum Bagging.
1183047
The ice melts as it is applied to the cloth and becomes water.  A process called osmosis then comes into play--the cells absorb the water until they burst, because the diffusion only goes INTO the cells; the water cannot otherwise escape.
127528
The moisture is a conduit to an electrical charge....The machine the Visa card was used on had the electicity...the normal moisture in an exhaled breath produced the small amount of fluid to be a conduit providing a connection .....NORMAL!  Getting rid of the dust as stated above is also...very true and very normal.  Not bizzare at all.
413190
Here is the best answer...\nhttp://science.howstuffworks.com/steam1.htm
931473
I have this very object. My foolish neighbor calls it an air humidifier, like he knows anything, ( he thinks we landed on the moon, I know crazy)\n     You can borrow it, but you have to come at night. My house is the one covered in tin foil and cloaked in the star trek special edition invisibility shield, with extra force field protons.
724981
I have used cryogenics to freeze lymphocytes from organ donors.  The goal in my clinical lab was to have a reference for cross-matching the donor lymphocytes (T and B cells) with the recipients blood, just in case a rejection episode occurred.\n\nRepeating the cross-match (should a rejection episode occur) allowed me to see if I made a mistake the first time around.  If I got the same negative cross-match, The surgeons would know that the rejection was not "acute", but was due to chronic rejection.  The medical approach to keep the organ recipient alive would be different for each type of rejection.\n\nBut back to your question:\n\nThe cells were preserved in a DMSO/H2O solution, and the cells and solution where placed in a special tube that would resist cracking at low temperature.  \n\nI would slowly freeze the cells over a few days to -80 degrees in a Styrofoam container.  Then I transferred the tube to a liquid nitrogen tank (I forget the temperature of liquid nitrogen, but you can google search for a quick answer, if your interested).  The cells would be good for about 10 years if stored like this.\n\nAnyway,  as I thawed the cells, I could usually depend on 50% loss of the cells (50% would die and 50% would still be viable). I knew this because I would take some of the cells and perform a "vital stain" which has a blue color to it.  If the dye was able to cross the cell membrane (making the cell blue), it indicated that the cell was dead.  If the cell membrane was able to resist the dye, it indicated that the cell membrane was intact and the cell was most likely still alive.\n\nI would say that if I froze you, and then brought you back "to life" 50% of your cells would be dead.  This surely would not be enough for you to be functional.\n\nGreat Question.  Pass on the good karma