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Cryogenic Safety for Space Launch Vehicles During Ground Operations

United Launch Alliance launches Atlas V from Cape Canaveral and Vandenberg Air Force launch facilities, and large quantities of cryogenic propellants are stored on-site. These propellants present leak, fire and explosion hazards throughout their handling, starting from the commercial transport trailers' arrival at the launch pad and continuing through storage...

Cryogenic Safety: An Introduction

The scope of cryogenics is vast, but in all its forms, cryogenics presents unique safety hazards, including issues associated with extreme cold, flammability, enhanced combustion due to the presence of liquid oxygen and oxygen displacement caused by gases boiling off from cryogenic liquids. Despite these hazards, if certain guidelines and...

Researchers characterize electron density wave in cuprates

A team led by researchers from the US Department of Energy's Brookhaven National Laboratory and Cornell University has characterized a key arrangement of electrons in a high temperature superconductor. The study, published in the October 26, 2015, online edition of Nature Physics, is the first to identify the atomic-scale origins...

New multi-SQUID device cuts costs, improves sensitivity

Physicists in the United Kingdom have built a multi-SQUID device that can operate at 77K, the boiling point of liquid nitrogen. According to research published in Applied Physics Letters, the new device outperforms the industry standard niobium/aluminium trilayer single-SQUIDS maintained at 4.2K. "Since our SQUID arrays operate at 77K using...

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Refrigerators and Liquefiers

Two of the most common terms used in cryogenics are “refrigerator” and “liquefier.” These terms describe similar and, as will be seen, in some cases identical components. A refrigerator provides cooling (that is, absorbs heat) at cryogenic temperatures. Refrigerators typically put a working fluid (such as helium) through one of...

Air Separation

Air separation is one of the largest, as well as earliest, industrial applications of cryogenics. In this process, cryogenic temperatures are used to separate air into its constituent gases: nitrogen (78.08%), oxygen (20.95%), argon (0.93%) and carbon dioxide (0.3%). Trace gases such as krypton, neon, xenon and helium total far...

Coefficient of Performance and Figure of Merit

The coefficient of performance (COP) is used to describe the effectiveness of refrigerators, including those operating at cryogenic temperatures. The COP is defined as the amount of heat removed at the cryogenic operating temperature of the refrigerator divided by the amount of work that must be applied to remove the...

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...

Power usage: cryogenic systems vs. regular refrigerators

A recent project highlighted to me that closed cycle cryogenic cooling systems use far more electrical power to reduce temperatures by a few watts than regular refrigerators. I am sure it must be something to do with the extra difficulty of removing the heat from the liquid nitrogen or similar...

Redundancy strategies for mechanical -80C freezers

I was wondering what kind of redundancy strategies are people using for their mechanical -80C freezers? I am aware of the following. Please add if you are doing something different. 1) 1 Backup freezer for every 10 freezers – Empty and maintained at -80C at all times 2) Backup C02...

Method to move components in a cryogenic environment

Does anyone know of a method with which to reliably move components in a cryogenic environment? We are interested in moving detectors in a cryogenically cooled (2K) vacuum chamber, which is contained within a larger cryostat/isolation vacuum with thermal shields. As the desired horizontal or vertical displacement is between 10...