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Space Systems Command Grants Contracts for Space Laser Communication Prototypes

The EST program, part of SSC’s Space Domain Awareness and Combat Power Program Executive Office, aims to create on-orbit crosslink compatibility among future space systems. This will be achieved through a standardized enterprise waveform implemented in a long-range space optical communications terminal that is low in size, weight, power, and...

Fusion Power Is Now a Possible Dream

Fusion power, the Holy Grail of nuclear energy for decades, may finally be within our grasp. If the scientists and engineers at Commonwealth Fusion Systems (CFS), a company with close ties to the Massachusetts Institute of Technology Plasma Science and Fusion Center, are right, fusion is nearly ready for power market...

Atomic Spreading Produces Novel Superconductors

Custom layering. A single layer of the topological insulator WTe2 (green) was placed on top of a row of palladium seeds (each roughly 0.5 µm wide). Over time, palladium atoms spread out across the layer and formed Pd7WTe2 (blue-green). The sample is shown before heating (left), after 25 minutes at 210 °C (center),...

100 Years of Quantum Is Just the Beginning

Recognizing the importance of quantum science and the need for wider awareness of its past and future impact, dozens of national scientific societies gathered together to support marking 100 years of quantum mechanics with a U.N.-declared international year. The timeline of endorsements for this international year also included the International Union of Pure and...

Cool It Down–Isochoric Preservation

If you’ve ever made the mistake of putting certain fresh fruits or vegetables in the freezer, then you’re already familiar with the effects of freezing on biological tissue. Banana skins turn black and slimy. Whole oranges leak and deflate. Lettuce comes out limp and soggy. The cause of all this...

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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....

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...