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Gravity Probe B demonstrates Einstein theory

A high-powered team of physicists and engineers has concluded that NASA’s $700 million Gravity Probe B (GP-B) experiment demonstrated two key aspects of Albert Einstein’s General Theory of Relativity, but not to the hoped-for degree of confidence.

KEK Director General assesses earthquake damage, tells repair plans

Atsuto Suzuki, Director General at KEK, the Japanese high energy accelerator research organization, reported on damage caused by the recent earthquake and recovery prospects in his “DG’s Corner” column: First of all, I would like to express my deepest appreciation for the messages of concern, sympathy and encouragement that we...

Superconductivity pioneer Paul Chu featured in exhibit

Superconductivity Pioneer Paul Chu was featured in an unusual exhibit in Texas. A white lab coat and a pair of worn sneakers are almost standard-issue items for a research facility, but they don't seem to rise to the rank of museum exhibit. Yet, that’s exactly where you can find one...

Paul Chu expected more progress by now

Superconductivity pioneer Dr. Paul Chu expected faster progress since his discoveries, he told Cold Facts Editor Theresa Boehl in a recent brief interview. Cold Facts: Did you have any idea of the potential impact of superconductivity when you were doing your groundbreaking research years ago? Chu: Yes, I think I...

Mathias Kläui Wins Kurti Science Prize

Oxford Instruments NanoScience announced that Professor Mathias Kläui from the SwissFEL, Paul Scherrer Institut and the Laboratory of Nanomagnetism and Spin Dynamics, École Polytechnique Fédérale de Lausanne, is the 2011 recipient of the Nicholas Kurti European Science Prize.

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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....

Magnets

From “Superconductivity: Present and Future Applications” by the Coalition for the Commercial Application of Superconductors. Particle physics uses accelerators to recreate the conditions of the early universe in an attempt to piece together the complex puzzle of how we got to where we are today. These huge machines are used...

Energy Storage

From “Superconductivity: Present and Future Applications” by the Coalition for the Commercial Application of Superconductors. With power lines increasingly congested and prone to instability, strategic injection of brief bursts of real power can play a crucial role in maintaining grid reliability. Small-scale Superconducting Magnetic Energy Storage (SMES) systems, based on...

Astronomy

ASTRONOMY IN SPACE by Peter V. Mason, retired,  Jet Propulsion Laboratory, and Visiting Associate, California Institute of Technology. Pmason@alumni.caltech.edu In thinking about the reasons to perform astronomy in space, we first consider the effect of the earth’s atmosphere.  On a scale of decreasing energy, gamma rays, cosmic rays, X-rays and...

Cryocoolers

What is a Cryocooler? A mechanism that can extract heat from an object (cooler) and by doing so draw its temperature down below approximately 150 Kelvin (cryo). — (Courtesy Dr. Willy Gully) What is the difference between a Cryocooler and a Cryostat? A cryostat is any device designed to maintain...

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...