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New RF-SQUID Material Invisible to Microwave Radiation

University of Maryland (UMD) physicists and engineers from HYPRES (CSA CSM) have developed a new RF-SQUID cloaking material that can become transparent to microwave radiation with the flip of a switch. The new material could be used to design more efficient communications networks since many wireless communication devices rely on...

DESY Research Points to Liquid Oxygen in Earth’s Core

Using a special high-pressure chamber, scientists have discovered two new iron oxides in experiments at DESY's X-ray light source PETRA III and other facilities. The discovery points to a huge, hitherto unknown liquid oxygen source in the lower mantle of the Earth. The team, led by Dr. Elena Bykova from...

Japanese Researchers Superconduct Graphene

Scientists in Japan have developed superconductive graphene, according to research published in ACS Nano. Graphene is a single-atomic carbon sheet with a hexagonal honeycomb network. Electrons in graphene take on a special electronic state called the Dirac-cone, where the electrons behave as if they have no mass. This allows the...

NASA Introduces WFIRST, a “Wider Set of Eyes” on the Universe

After years of preparatory studies, NASA is formally starting an astrophysics mission designed to help unlock the secrets of the universe—the Wide Field Infrared Survey Telescope (WFIRST). With a view 100 times bigger than that of NASA’s Hubble Space Telescope, WFIRST will survey large regions of the sky in near-infrared...

Gravitational Waves Detected 100 Years after Einstein’s Prediction

Scientists have for the first time observed ripples in the fabric of spacetime called gravitational waves, confirming a major prediction of Albert Einstein’s 1915 general theory of relativity and opening an unprecedented new window onto the cosmos. The discovery was made possible by the enhanced capabilities of Advanced LIGO, a...

Researchers Designing Safer Cryotherapy Devices

Researchers at the University of Texas at Arlington and the University of Texas at Austin are developing a state-of-the-art cryotherapy device, one that can stimulate blood flow to keep tissue healthy and minimize potential side effects, and what are believed to be the first formal protocols for effective and safe...

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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 Electronics

Randall Kirschman, consulting physicist, Mountain View, California ExtElect@gmail.com Cryogenic electronics—the operation of electronic devices, circuits, and systems at cryogenic temperatures—has been a valuable technology for decades. Cryogenic electronics (also referred to as low-temperature electronics, or cold electronics) can be based on semiconductive devices, on superconductive devices, or on a combination...

Particle Physics: High Energy Physics

Cryogenics and High-Energy Physics 1. From symmetry magazine: http://www.symmetrymagazine.org/cms/?pid=1000627: Cryogenics is the study of how materials behave at temperatures near absolute zero. In high-energy particle accelerators, such frigid temperatures reduce the electrical resistance of wires in superconducting magnets, increasing the magnet strength and allowing faster particle acceleration. The same holds...

HTS Degaussing Systems

From the Spring 2009 issue of Cold Facts (Volume 25, Number 2): Thanks to a joint project by the US Navy and a number of industry partners, high temperature superconducting (HTS) technology is now at the heart of an advanced degaussing system aboard the USS Higgins at the naval station...

Magnetic Resonance Imaging

From http://www.superconductors.org: An area where superconductors can perform a life-saving function is in the field of biomagnetism. Doctors need a non-invasive means of determining what’s going on inside the human body. By impinging a strong superconductor-derived magnetic field into the body, hydrogen atoms that exist in the body’s water 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...