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A final answer on how high-temperature superconductors don’t work?

For decades, physicists have debated the origins of high-temperature superconductivity—the ability of some materials to carry electricity without resistance at temperatures up to 138 kelvin. Now, new data nix one possible explanation, albeit a less popular one, a team claims. If the finding holds up, it would sever any connection...

Copper-based materials show strange spin states

Just as water, ice, and steam are all phases of the same material that are influenced by temperature and pressure, new research shows how transitions of state work in very simple lattices primarily composed of copper.

Neutrons uncover new density waves in fermion liquids

Scientists working at the Institut Laue-Langevin, the world’s flagship center for neutron science, have carried out the first investigation of two-dimensional fermion liquids using neutron scattering, and discovered a new type of very short wave-length density wave.

Air Liquide and Astrium create EuroCryospace

Air Liquide and Astrium have announced the creation of EuroCryospace, the new European expansion of Cryospace, created nearly 25 years ago by both companies, for the development and production of Ariane cryogenic tanks.

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Mixed Refrigerant Cycles

Most cryogenic refrigeration systems, both large scale systems and cryocoolers, use helium as a working fluid. There are a number of advantages to helium, not the least of which is that helium remains a fluid down to the lowest achievable temperatures. In order to freeze helium, pressures of over 20...

Fountain Pumps and He II Phase Separators

Helium II (He II), the second liquid phase of the 4He isotope described in this column in Cold Facts Spring 2010 (http://2csa.us/he2), can be modeled as consisting of two interpenetrating fluids. One, the superfluid component, has zero viscosity and entropy and the other, the normal fluid component, has nonzero viscosity...

Turboexpanders

A vital technology in the refrigerators and liquefiers described in Cold Facts Volume 31 Number 3 is that of turboexpanders. These devices are rotating machines in which the process fluid (e.g., helium) does work against the turboexpander while moving from high pressure to a lower pressure and thus is cooled....

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...