ADVERTISEMENT

Potential of molybdenum disulfide for extreme-temperature electronics

Many industries are calling for electronics that can operate reliably in a harsh environment, including extreme temperatures above 200°C. A team of researchers from the University of California, Riverside and Rensselaer Polytechnic Institute discovered that molybdenum disulfide, a semiconductor material, may be a promising candidate to make thin-film transistors for...

Maglev elevators go up, down and sideways

Elevators are about to get a major upgrade: the ability to go sideways, thanks to magnetic levitation technology. German industrial behemoth ThyssenKrupp is promising that two-axis travel ("the holy grail of the elevator industry") will revolutionize intra-building travel, and that they will have it operational in 2016.

Evidence mounts for quantum criticality theory

A new study by a team of physicists adds to the growing body of evidence supporting a theory that strange electronic behaviors, including high temperature superconductivity and heavy fermion physics, arise from quantum fluctuations of strongly correlated electrons. The study describes results from a series of experiments that tested for...

Charge instability detected across all types of copper-based superconductors

A recent study by physicists from the University of British Columbia and the University of Maryland detected for the first time in electron-doped cuprate superconductors evidence of charge ordering, a phenomenon that appears to compete with superconductivity and reduce the temperature at which cuprates demonstrate superconducting properties. The study's findings...

A 50-Year History of the Extended Bonnet Cryogenic Valve

Many cryogenic products have been developed out of necessity over the past 50 years. One such product is the vacuum jacketed extended bonnet cryogenic valve. Currently there are numerous manufacturers in the US and abroad that have utilized design basics developed over 50 years ago. One of the main contributors...

ADVERTISEMENT

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....

Primary Standards

Elie K. Track Hypres, Inc. elie@hypres.com http://www.hypres.com/ Primary standards involve the exact definition and realization of units of measurement for various quantities, time, length, mass, voltage, resistance, current, etc. International agreements based on the latest scientific knowledge define those units, and their realizations vary depending on the unit itself. For...

Shrink Fitting

Robin A. Rhodes Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Shrink fitting, (or “compression fitting” as it is sometimes called), is a method used to insert a pin or bushing into a housing or other assembly requiring an extremely tight tolerance fit. It can be used as an alternative to...

Telecommunications

From the Winter 2004 issue of Cold Facts magazine The recent M-Calc IV — 4th Industry Assessment workshop discussing military and commercial applications for low-cost cryocoolers, held in November in San Diego, highlighted progress being made in cryogenics as applied in telecommunications. The reliability and long lifetime of projects now...

Wind Tunnels

Dr. Robert Kilgore The development of the cryogenic wind tunnel is one of many significant breakthroughs in both cryogenics and wind-tunnel technology made during the past millennium. Interest in the development of high-speed commercial and military aircraft resulted in a review of problems of flow simulation in transonic wind tunnels...

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...