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The Next Niobium Goal: Medium-Field SRF Cavities with High Quality Factor

In his guest column, Dr. Lance Cooley writes, "We are now beginning to evolve our present knowledge about producing high-gradient cavities to take on goals of high-Q CW cavities. The starting point for this transition is clearly to explore simple adaptations of the present ILC process. But it is not...

American College of Cryosurgery Holds Annual Meeting

The American College of Cryosurgery, founded in 1977, hosted its first meeting January 2-7, 2013, after a hiatus of nearly ten years. The meeting venues provided a unique experience for participants and accompanying guests. A land-based session was held at the Hyatt Regency Downtown Miami Hotel.

Donnelly Team Designs Cryogenic Remediation of Power Pollutants

Professor John M. Pfotenhauer writes, "The fields of low temperature physics and energy and environment do not frequently interact. Imagine my astonishment to find in the 2010 spring edition of a newsletter from the Department of Physics at my graduate school, the University of Oregon, that my thesis advisor from...

Cryo Community Mourns Donna Jung, International Cryogenics

It is with great regret that we report the sudden death of Donna Jung, President of International Cryogenics, on February 1, 2013. Jung was a leader in the cryogenic community, president of a longtime CSA Corporate Sustaining Member company, and a stalwart supporter of the Society. Jung, 52, was one...

Rules of thumb for the design length of transition tubes

Are there any rules of thumb for the design length of transition tubes in order to prevent condensation at the room temperature end? By “transition tube,” I mean some standard size (O.D. and wall thickness) type 304 stainless steel tube with either 4 K or 80 K at one end...

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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....

Food Processing

Cryogenics and Food The industrial gas industry provides a host of products and services related to food. The various gases have useful and sometimes fascinating applications in food industry. “The food industry is not a homogenous industry. The needs of customers processing hamburger vs. poultry vs. strawberries vs. seafood, for...

Primary Standards

Elie K. Track Hypres, Inc. elie@hypres.com http://www.hypres.com/ Primary standards involve the exact definition and realization of units of measurement for various quantities, time, length, mass, voltage, resistance, current, etc. International agreements based on the latest scientific knowledge define those units, and their realizations vary depending on the unit itself. For...

Shrink Fitting

Robin A. Rhodes Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Shrink fitting, (or “compression fitting” as it is sometimes called), is a method used to insert a pin or bushing into a housing or other assembly requiring an extremely tight tolerance fit. It can be used as an alternative to...

Telecommunications

From the Winter 2004 issue of Cold Facts magazine The recent M-Calc IV — 4th Industry Assessment workshop discussing military and commercial applications for low-cost cryocoolers, held in November in San Diego, highlighted progress being made in cryogenics as applied in telecommunications. The reliability and long lifetime of projects now...

An Issue of Pressure and Flow Rate in a Supply Tank

Please help solve this problem: A supply tank requires a vaporizer to generate sufficient pressure to pump stored fluid up into a vehicle or tank. The available head is limited as the tank level falls and it is important to minimize the system pressure drop to maintain the desired flow...

Using MLI on VJ Line Joints or Cryo Storage Tanks

When installing Multi Layer Insulation (MLI) blankets on VJ line joints or cryo storage tanks should they be wrapped and tied down tight or loose? These are usually pre-cut to size. Also should they have an access hole at the point of where the molecular sieve is installed to help...