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Standards for cryogenic valves
Do you know where I can get some documents of testing specification or US standards for cryogenic valves (DN 250)? Or could you give me some suggestion for that?
Recent material and fabrication developments in low-temperature regeneration
In the area of low-temperature regeneration, what are some recent material and fabrication developments?
Vendors for cryopreserved rat arteries
My department is starting up a microsurgery training lab as an adjunct to our resident curriculum. Instead of using live rats, we want to pursue the option of using cryopreserved rat arteries. I have been unsuccessful in finding animal/rodent vendors who deal in this. I basically found a lot of...
Source for pressure switch
Where can I find a pressure switch operating in the range 0.2 to 0.4 psi which is not affected by magnetic fields up to about 1000 Gauss?
Cryostat for storing fish samples at -20 degrees C
We are a small Food Chemistry Laboratory functioning within the Seychelles Bureau of Standards. We wish to purchase a cryostat for the purpose of storing fish samples at *-20ºC* prior to the analysis of Histamine in the tissue of Tuna by HPLC.
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Cold Compressors
A common way to provide cooling below the normal boiling point of helium (4.2K) is to reduce the pressure above the bath of liquid helium, thus also reducing the bath’s equilibrium saturation temperature. For example, to produce a 1.8K bath of liquid helium, the saturation pressure has to be reduced...
Kapitza Conductance
Kapitza conductance refers to the heat transfer between a solid surface and a fluid that covers that surface. Fundamentally, it describes the inherent difficulty in transferring energy from a solid to the fluid covering the solid surface. This phenomenon was first observed by P. L. Kapitza in 1941 while studying...
Thermosyphons
A thermosyphon (or thermosiphon) is a device that transfers heat via natural convection in a fluid. The natural convection is driven by gravity with the colder, denser fluid flowing downhill and the warmer, less dense fluid flowing back up. Thus, thermosyphons connect an object to be cooled with a reservoir...
Air Separation and Liquefaction
by Nils Tellier, PE, President, EPSIM Corporation (CSA CSM) nils@epsim.us All illustrations courtesy EPSIM Corporation Background History of Air Separation and Liquefaction This section builds on a rich history of methods to develop deep refrigeration and cryogenic liquefaction during the 19th Century. You are encouraged to read Cryo Central’s History...
Bose-Einstein Condensate
A Bose-Einstein condensate, first proposed in 1925 by Albert Einstein based on work done by Satyendra Nath Bose (the same Bose from whom the term boson is derived), is a super-cold state of matter in which almost all of the individual atoms have “condensed” down to the lowest possible quantum...
Cold Technology for Pest Control
While it does not reach temperatures cold enough to be called cryogenic, carbon dioxide snow is at the heart of a new way of dealing with unwanted pests. It utilizes a quick freezing process that takes advantage of the properties of carbon dioxide snow and has a number of benefits...
Cryogenic Finishing
The following 3 articles discuss the uses and procedures of various type of cryogenic finishing. 1) By Robin A. Rhodes, Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Cryogenic Deflashing is employed to remove undesired residual mold flash that remains on molded parts after they are removed or ejected from the...
Suppliers of regenerator materials
I was looking for suppliers of regenerator materials. Can you please provide a list of vendors for: • Lead spheres • Bronze screen discs • Rare earth materials and spheres Thank you in advance for any help you can provide.
Containing ice accumulation while recovering helium
We are implementing a system to recover helium from our Janis ST-500 continuous flow LHe cryostat. The recovery system uses standard 1/4″ plastic tubing, which we connect directly to the cryostat’s exhaust port. The problem with this setup is that the gas is still quite cold as it leaves the...
Looking for some advice regarding cryogenic modeling in ANSYS FEA software
I am looking for some advice regarding cryogenic modeling in ANSYS FEA software. I have been trying to use the Transient Thermal module, in workbench 14.5, to model the cooling of a device in a dilution fridge. I have approximate values for the cooling power of each plate in the...
Compensators and/or accumulators: Are they used in cryogenics?
Are compensators and/or accumulators, high or low pressure, used in cryogenics? Are they used in space?