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MicroBooNE detects accelerator-born neutrinos

The MicroBooNE collaboration announced on November 2 that its researchers had recorded neutrinos for the first time. The sighting marks the beginning of detailed studies of these fundamental particles whose properties could be linked to dark matter, matter’s dominance over antimatter in the universe and the evolution of the entire...

Layered Thermal Insulation Systems for Below-Ambient Temperature Applications

With increasing system control and reliability requirements as well as demands for higher energy efficiencies, thermal insulation in extreme environments is a growing challenge prompting the publication of new technical consensus standards for cryogenic insulation testing and multilayer insulation (MLI) systems. Different layered thermal insulation systems such as MLI and...

Cryogenic Safety for Space Launch Vehicles During Ground Operations

United Launch Alliance launches Atlas V from Cape Canaveral and Vandenberg Air Force launch facilities, and large quantities of cryogenic propellants are stored on-site. These propellants present leak, fire and explosion hazards throughout their handling, starting from the commercial transport trailers' arrival at the launch pad and continuing through storage...

Cryogenic Safety: An Introduction

The scope of cryogenics is vast, but in all its forms, cryogenics presents unique safety hazards, including issues associated with extreme cold, flammability, enhanced combustion due to the presence of liquid oxygen and oxygen displacement caused by gases boiling off from cryogenic liquids. Despite these hazards, if certain guidelines and...

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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...

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...