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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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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)...

Cryogenic Treatment of Materials

F.J. Diekman Controlled Thermal Processing, Inc. info@metal-wear.com Cryogenic Processing (also called cryogenic treatment, and incorrectly “cryogenic tempering”) is a process that uses cryogenic temperatures to modify materials to enhance their performance. Cryogenic Processing involves the slow reduction in temperature of the material to at least -300°F (-185°C) and holding the...

Cryogenics in Space

Peter Kittel University of California-Berkeley pkittel@cal.berkeley.edu Space Cryogenics is the application of cryogenics to space missions. These applications fall into two broad areas, supporting space science missions and supporting the space transportation infrastructure. Science applications: The atmosphere is opaque to much of the electro-magnetic spectrum. In space, the absence of...

Cryosurgery

Review of Cryosurgery Boris Rubinsky, PhD Hebrew University School of Science and Engineering Research Center for Biomedical Engineering 78b Ross Building Givat Ram, Jerusalem 91904 Israel rubinsky@cs.huji.ac.il as published in Annual Review of Biomedical Engineering, August 2000, Vol. 2, pp. 157-187. Abstract: Cryosurgery is a surgical technique that employs freezing...

Liquefied Natural Gas

Liquefied Natural Gas as it relates to the Field of Cryogenics John W. Bonn VJ Systems, LLC johnbonn@vjsystems-lic.com Today the world is looking for a cleaner fuel and Liquefied Natural Gas (LNG) plays a large part in achieving this goal. LNG in a liquid form is at -162°C (-259°F) and...

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...