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LIGO Detects Gravitational Waves for a Second Time

Scientists from the LIGO Scientific Collaboration have observed gravitational waves for a second time, according to an announcement made on June 15 during the 228th meeting of the American Astronomical Society in San Diego. The detection of the waves—ripples in the fabric of spacetime—was made on Dec. 25 by both...

EMIR Spectrograph Installed on Gran Telescopio CANARIAS

Engineers at the Roque de los Muchachos Observatory have attached the EMIR spectrograph to the Gran Telescopio CANARIAS (GTC), realizing a more than decade long design and fabrication process. The cryogenic instrument was designed, built, assembled and verified entirely at the IAC (Astrophysics Institute of Canrias). It will produce images...

FAST Research Accelerator Reaches Design Beam Energy

In May, Fermilab sent an electron beam with an energy of 50 million electronvolts, or MeV, through the photoinjector at the Fermilab Accelerator Science and Technology facility (FAST), achieving a major design goal for the accelerator and marking the beginning of a new accelerator science program at the laboratory.

New Elements Named, Public Comment Sought

The International Union of Pure and Applied Chemistry (IUPAC) has opened a five-month long public comment and review period of the names recommended for elements 113, 115, 117 and 118, the discoveries of which were announced late last year.

Scientists Use Frozen Argon to Boost Laser Light to New Extremes

Researchers at the Department of Energy’s SLAC National Accelerator Laboratory, Stanford University and Louisiana State University have achieved a dramatic high harmonic generation (HHG) shift by shining an infrared laser through argon gas that’s been frozen at 20 K into a thin, fragile solid whose atoms barely cling to each...

New Low-Defect Method to Nitrogen Dope Graphene Results in Tunable Bandstructure

An interdisciplinary team of scientists at the US Naval Research Laboratory (NRL) Electronics Science and Technology and Materials Science and Technology Divisions has demonstrated hyperthermal ion implantation (HyTII) as an effective means of substitutionally doping graphene—a hexagonally-arranged single-atomic thickness carbon sheet—with nitrogen atoms. The result is a low-defect film with...

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Refrigerators and Liquefiers

Two of the most common terms used in cryogenics are “refrigerator” and “liquefier.” These terms describe similar and, as will be seen, in some cases identical components. A refrigerator provides cooling (that is, absorbs heat) at cryogenic temperatures. Refrigerators typically put a working fluid (such as helium) through one of...

Air Separation

Air separation is one of the largest, as well as earliest, industrial applications of cryogenics. In this process, cryogenic temperatures are used to separate air into its constituent gases: nitrogen (78.08%), oxygen (20.95%), argon (0.93%) and carbon dioxide (0.3%). Trace gases such as krypton, neon, xenon and helium total far...

Coefficient of Performance and Figure of Merit

The coefficient of performance (COP) is used to describe the effectiveness of refrigerators, including those operating at cryogenic temperatures. The COP is defined as the amount of heat removed at the cryogenic operating temperature of the refrigerator divided by the amount of work that must be applied to remove the...

Food Processing

Cryogenics and Food The industrial gas industry provides a host of products and services related to food. The various gases have useful and sometimes fascinating applications in food industry. “The food industry is not a homogenous industry. The needs of customers processing hamburger vs. poultry vs. strawberries vs. seafood, for...

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...

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...