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Stephen Hawking Dies at 76, Cosmos Pauses to Welcome Its Brightest Star

Stephen Hawking died in the early hours of March 14 at age 76. His insights helped shape modern cosmology and he is widely credited with inspiring millions worldwide to look to the stars and challenge conventional thought. "He was a great scientist and an extraordinary man whose work and legacy...

Wunderkind Material is Both Superconductor and Insulator

Physicists at MIT and Harvard University report that graphene can exhibit a curious electronic property, behaving both as an insulator—where electrons are completely blocked from flowing—and as a superconductor—where electrical current can stream through without resistance.

Book Review: Thermodynamic Properties of Cryogenic Fluids

An accurate knowledge of the thermodynamic properties of fluids is one of the cornerstones of cryogenic engineering. These properties, which vary greatly with temperature and pressure, drive refrigeration cycle design, safety analysis and overall cryogenic system design. Having access to these properties and knowing the accuracy of their values is...

Superconducting Magnet Sets 32-T World Record

The National High Magnetic Field Laboratory (CSA CSM) chalked up another world record in December when a new superconducting magnet at the facility reached a magnetic field of 32 teslas, a third stronger than the previous record and more than 3,000 times stronger than a common refrigerator magnet.

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Cold Compressors

A common way to provide cooling below the normal boiling point of helium (4.2K) is to reduce the pressure above the bath of liquid helium, thus also reducing the bath’s equilibrium saturation temperature. For example, to produce a 1.8K bath of liquid helium, the saturation pressure has to be reduced...

Kapitza Conductance

Kapitza conductance refers to the heat transfer between a solid surface and a fluid that covers that surface. Fundamentally, it describes the inherent difficulty in transferring energy from a solid to the fluid covering the solid surface. This phenomenon was first observed by P. L. Kapitza in 1941 while studying...

Thermosyphons

A thermosyphon (or thermosiphon) is a device that transfers heat via natural convection in a fluid. The natural convection is driven by gravity with the colder, denser fluid flowing downhill and the warmer, less dense fluid flowing back up. Thus, thermosyphons connect an object to be cooled with a reservoir...

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...