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Cryopump Systems and Space Telescopes

In the 21st century, NASA and the world have started looking into deep space astrophysics. Acquiring deep space images requires a space telescope with a large optical mirror, such as the James Webb Space Telescope (JWST), the Planck telescope, the Herschel telescope, etc. To carry out various space missions at...

Tributes to Professor Joseph L. Smith, Jr.

We regret to report that Professor Joseph LeConte Smith Jr., the Samuel C. Collins Professor Emeritus of Mechanical Engineering at MIT, died on May 7 at the age of 83. Following are tributes from his friends and colleagues.

Tributes to Dr. Frederick J. Edeskuty

Dr. Frederick J. Edeskuty, 89, longtime CSA member, Cold Facts columnist and expert on cryogenic safety, passed away on Friday, May 10. The following tributes were sent to CSA by friends and colleagues of Edeskuty.

Cold Facts Tours Field Museum’s Cryo Storage Facility

Cold Facts was privileged to spend a morning with Dr. Shannon Hackett, the Richard and Jill Chaifetz Associate Curator, Head, Bird Division, Zoology Department, at Chicago’s Field Museum of Natural History. We wanted to learn more about the museum’s cryogenic storage facility and its role in the collections and research...

Report on Third New York State Superconductor Summit

At the hub of New York’s Tech Valley region, business leaders, academia, prominent scientists, engineers and government officials gathered at the College of Nanoscale Science and Engineering (CNSE) campus in Albany on May 7 for the third New York State Superconductor Technology Summit.

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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....

Magnetic Levitation

From http://www.superconductors.org. Magnetic-levitation is an application where superconductors perform extremely well. Transport vehicles such as trains can be made to “float” on strong superconducting magnets, virtually eliminating friction between the train and its tracks. Not only would conventional electromagnets waste much of the electrical energy as heat, they would have...

Superconductivity

From Superpower website. History of Superconductivity Superconductivity was discovered in 1911 by the Dutch physicist, Heike Kammerlingh Onnes when he was able to liquefy helium by cooling it to 4 Kelvin, or -452°F. This enabled him to cool other materials close to absolute zero and investigate their electrical properties. He...

Medical Applications of Cryogenics

Neutron Therapy Cryogenics is at the heart of nuclear accelerators. Accelerators such as Fermilab’s Tevatron make neutron therapy for cancer possible. From Fermilab Today 4/20/09: Fermilab currently offers neutron therapy. But staff at Fermilab designed and built the proton accelerator used by the nation’s first hospital-based treatment center to use...

Nuclear Physics

Al Zeller National Superconducting Cyclotron Lab (NSCL) at Michigan State University zeller@nscl.msu.edu Cryogenics has a long history in nuclear physics. The technology has its origins in the use of cold traps for maintaining a vacuum, which is required to prevent beam loss and for generating high voltages used in acceleration....

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...