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New test using cryogenic sapphire oscillators confirms speed of light

Researchers from the University of Western Australia and Humboldt University of Berlin used cryogenic temperatures to optimize frequency stability in a test designed to measure the spatial consistency of the speed of light with a precision ten times greater than ever before. The experiment compared the extremely pure microwave frequency...

Young Faces: The Next Generation in Cryogenics

We're pleased to present a new installment of Young Faces, a feature story we debuted in the Summer 2006 issue of Cold Facts introducing outstanding young professionals (under 40 years of age) who are doing interesting things in cryogenics and superconductivity and who show promise of making a difference in...

CSA Awards Presented at CEC/ICMC

John Weisend, CSA chairman, presented four awards at CEC/ICMC on July 1, including the first-ever William E. Gifford Award, given to a recipient in academia or at a government laboratory using a pulse tube or Gifford-McMahon cycle cryocooler as a key research component.

The 26th Space Cryogenics Workshop

This column presents a topical summary of the 2015 Space Cryogenics Workshop that was held June 24-26 in Phoenix AZ. The workshop was organized by David Plachta and Jason Hartwig of NASA/Glenn Research Center, and continued the tradition of bringing together specialists in the field of space cryogenics to discuss...

An Introduction to LNG as a Cryofuel

Technological advances in the US have unlocked massive quantities of natural gas, resulting in an abundant supply that should easily last many decades. This sustained situation has created two important consequences: the price of pipeline natural gas is low and stable, and, more significantly, the price of pipeline natural gas...

Improving the Efficiency of Helium Transfer Tubes

One must, on a daily basis, transfer liquefied gases, most notably helium from large static tanks or dewars to smaller transportable vessels. This process can become costly due to the losses sustained during transfer, which must be compensated for by reliquefying helium, requiring between 2 and 5 kW per liquid...

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Dilution Refrigerators

Dilution refrigerators are a common technique for reaching temperatures below 1K, particularly where continuous cooling at these temperatures is required. Helium exists in two stable isotopes: 4He and 3He. Naturally occurring 3He is extremely rare, constituting less than 1 part per million of helium gas. However, 3He can be manufactured,...

Oxygen Deficiency Hazards

Oxygen Deficiency Hazards (ODH) are a significant safety issue in cryogenic facilities. ODH occurs when inert gases such as nitrogen, helium or argon displace room air and thus lower the percentage of oxygen in the space below that required for human life. OSHA defines an area as oxygen deficient if...

Kelvin Temperature Scale

The Kelvin temperature scale is the principal temperature scale used in cryogenics and science. The kelvin is also one of the seven base units in the Système International d’Unités (SI) and is the unit of thermodynamic temperature. Thermodynamic temperature is a fundamental physical quantity (like mass, length or electrical current)...

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...