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World record quality factor achieved at Fermilab

Earlier this year, Fermilab scientist Anna Grassellino began researching past successes and failures of accelerator cavities made of bulk-diffused niobium-nitride. Scientists reported less-than-stellar results in their tests in the 1990s and, in the years since, appeared to have mostly abandoned the material as a possibility for superconducting cavities. But Grassellino...

First room-temperature maser developed

British researchers have, for the first time, built a prototype solid-state maser that works at room-temperature, with no permanent applied magnetic field.

Estimating cost for components of a helium plant

I have to perform a cost estimation of our helium cryogenic plant design. I based it on the formula discussed in the following article “THE COST OF HELIUM REFRIGERATORS AND COOLERS FOR SUPERCONDUCTING DEVICES AS A FUNCTION OF COOLING AT 4 K” by M. A. Green: C(M$) = 2.6 [R(kW)]^0.63...

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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...

Cryogenic thermophysical property data

I am in search of information regarding cryogenic thermophysical property data, specifically, Thermal Conductivity, Thermal Expansion, Stiffness and Modulus, in the 20K range. My list of materials include: Ti-6AL-4V (ELI), Al 6061-T651, and Invar (36%, plus any other composition which might have data available). Other materials which would be helpful...