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Sealing Options for Aluminum Vacuum Chambers

The goal of any sealing option for a vacuum chamber, whether aluminum or another material, is to provide a leak free (or acceptable leak rate) transition from the interior vacuum of the chamber to the exterior environment. For all types of vacuum chambers these options fall into two broad categories:...

Cool Fuel: Bias and Green versus Blue Hydrogen

I was ready to write about the awesome green beauty of a 454.6 nm argon laser and what it does to the hydrogen molecule when a friend sent me an article from the New York Times by Hiroko Tabuchi, “For many hydrogen is the fuel of the future. New research...

In Memoriam: Peter Mason 1928-2021

We regret to report the passing of former Jet Propulsion Laboratory (JPL) leader, visiting associate at Caltech, CSA Fellow and Cold Facts Space Cryogenics columnist, Peter V. Mason. He passed after a short illness on May 30, 2021.

Qubit Measurement Systems Right Out of the Box?

During past years, advances in both lithography and millikelvin cryogenics have supported and enabled vast improvement in the sophistication of experimental research on electrical circuits that display uniquely quantum mechanical behavior. It comes as no surprise that dilution refrigerator measurement systems have moved beyond basic physics research contraptions and into...

International Cryogenic Research, Industry Leaders Meet for Virtual CEC-ICMC ’21

While the pandemic may have changed the approach, organizers and attendees of the 2021 Cryogenic Engineering Conference–International Cryogenic Materials Conference participated in a valuable week of presentations, discussions, posters, short courses and exhibitions. Held virtually via Whova® from July 17–23, CEC-ICMC hosted over 670 attendees from across the globe in...

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Helium-3

Helium-3 (3He) is one of the two stable isotopes of helium. The other is the much more common Helium-4 (4He). Neither of these isotopes should be confused with He II, which is the second liquid phase of 4He. He II was discussed in this column in the Spring 2010 edition...

Cryopumping

Cryopumping refers to the use of cryogenic temperatures to produce vacuum in enclosed spaces. More broadly, it can also refer to the removal of gases via cryogenic temperatures from a flow stream or enclosure without necessarily resulting in vacuum pressures. This is an important application of cryogenics and is used...

Thermal Acoustic Oscillations

Thermal Acoustic Oscillations (TAO) are a common event in cryogenic systems that can have significant adverse effects on the performance of the system. TAOs are sustained pressure oscillations that can occur in tubes containing gas, closed at one end (the warm end) that have a very large temperature gradient along...

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...

Approximating pressure changes over time in cryogenic cylinders

I am an Air Resources Engineer with the California Air Resources Board (CARB). My senior management has asked me to investigate approximating pressure changes over time in cryogenic cylinders that contain LNG. So far, I have taken a stab at the problem, seeking to take a back-of-the-envelope approach (as directed...