Cold Facts Digital – Page 63 – The go-to place for Cryogenics and Superconductivity

Boiloff Calorimetry for the Measurement of Very Low Heat Flows

The use of boiloff calorimetry to measure the effects of thermal energy (or heat) dates back to the early 1900s [1, 2]. Gas flow rates measured in evaporation—or boiloff—calorimetry enable direct calculation of quantities such as heat flux and thermal conductivity. A particularly useful approach is to use nitrogen for...

Remembering the 1987 Woodstock of Physics

Paul Michael Grant was in the room where it happened, and in this essay, he recalls the 1987 APS March Meeting known as the "Woodstock of Physics." It began when Brian Maple, of UC San Diego, took the unprecedented and ambitious step of assembling an “off the program” all night...

Women in Cryogenics and Superconductivity

CSA celebrates women in cryogenics and superconductivity. In this feature, six women in positions across the industry discuss current projects, how they entered the field and their thoughts on attracting more women to the profession.

Cryogenic Sapphire Oscillator Enhancement Improves Accuracy

Researchers from the University of Adelaide in South Australia have enhanced the Cryogenic Sapphire Oscillator, or Sapphire Clock, to allow time measurements with accuracy on the femtosecond scale. The oscillator has a five-centimeter cylinder-shaped sapphire crystal cooled to about -267°C, or about five or six degrees above absolute zero. At...

The Robots of CERN

The LHC contains 120 tons of liquid helium kept at 1.9 K. And even with safety systems in place, engineers there prefer to limit underground access when the cryogenic systems are activated. Enter TIM—the Train Inspection Monorail. TIM is a chain of wagons, sensors and cameras that snake along a...

NASA Telescope Reveals Batch of Earth-size, Habitable-zone Planets around Single Star

NASA's Spitzer Space Telescope has revealed a new exoplanet discovery: the first known system of seven Earth-size planets around a single star. Three of these planets are firmly located in the habitable zone, the area around the parent star where a rocky planet is most likely to have liquid water.

Latest in Defining Cryogenics

Dewar

A dewar is a type of cryostat named after Sir James Dewar, the researcher who first developed the concept of a vacuum insulated container with silvered walls to reflect thermal radiation. Dewar was the first to liquefy hydrogen, and he created the device to store his discovery. The thermos bottle...

Stirling and Gifford-McMahon Cryocoolers

Stirling and Gifford-McMahon (GM) cryocoolers are two of the most commonly used cryocoolers in cryogenics. Both devices have a significant industrial base and operate at a wide range of temperatures and capacities. The thermodynamic cycles for both of these cryocoolers are quite similar. The Stirling cycle consists of a compressor,...

Liquefied Natural Gas (LNG)

A significant commercial application of cryogenics is the liquefaction, transport and storage of natural gas. Liquefied Natural Gas (LNG) is generally 95 percent methane with a few percent ethane and much lower concentrations of propane and butane. LNG liquefies at 111.6 K. Unlike many applications of cryogenics, the motivation for...

Latest in Cryo Central

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...

Latest in Ask the Experts

Power usage: cryogenic systems vs. regular refrigerators

A recent project highlighted to me that closed cycle cryogenic cooling systems use far more electrical power to reduce temperatures by a few watts than regular refrigerators. I am sure it must be something to do with the extra difficulty of removing the heat from the liquid nitrogen or similar...

Redundancy strategies for mechanical -80C freezers

I was wondering what kind of redundancy strategies are people using for their mechanical -80C freezers? I am aware of the following. Please add if you are doing something different. 1) 1 Backup freezer for every 10 freezers – Empty and maintained at -80C at all times 2) Backup C02...

Safety guidelines for handling cryo vessels of nitrogen

I am looking for any safety guidelines for handling cryogenic vessels of nitrogen indoors and outdoors. I am especially interested in recommendations for area monitors to detect leaks, flow detection devices, etc.

Method to move components in a cryogenic environment

Does anyone know of a method with which to reliably move components in a cryogenic environment? We are interested in moving detectors in a cryogenically cooled (2K) vacuum chamber, which is contained within a larger cryostat/isolation vacuum with thermal shields. As the desired horizontal or vertical displacement is between 10...

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