First room-temperature maser developed
British researchers have, for the first time, built a prototype solid-state maser that works at room-temperature, with no permanent applied magnetic field.
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Estimating cost for components of a helium plant
I have to perform a cost estimation of our helium cryogenic plant design. I based it on the formula discussed in the following article “THE COST OF HELIUM REFRIGERATORS AND COOLERS FOR SUPERCONDUCTING DEVICES AS A FUNCTION OF COOLING AT 4 K” by M. A. Green: C(M$) = 2.6 [R(kW)]^0.63...
How much heat energy does LN2 contain per lb.?
I would like to know how much heat energy liquid nitrogen contains per lb. In other words, per lb. of liquid, how many BTUs of heat would N2 absorb in the process of coming up to about 60F? I want to capture the cold energy of nitrogen as it vaporizes...
Software for thermophysical properties of helium down to 1K
What are the options when it comes to software for thermophysical properties of helium at temperatures down to 1K? I know Hepak – is it still the most commonly used package?
Refilling process of a helium cryogenic plant
I’m trying to collect some information about the refilling process of a helium cryogenic plant. Due to the physiologic losses I expect to have to foreseen a periodic refilling of helium. Our plant will be characterized by a refrigerator/liquefactor. A control cryostat with 4.5 K LHe coming from the liquefactor...
What's the best gas to use for pulse GMAW?
I have a 78″ ID vessel, 3/8″ thick shells, ½” heads, from SA-240-304L, which will have an ASME U-Stamp and I am planning on sub-arcing the seams and using pulse GMAW (ER308L for both) for the nozzles. I am comfortable with the SAW, but I am wondering about the best...
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Stability
Stability refers to the ability of a device employing superconductors to remain in its superconducting state after part of the superconductor transitions back to its normal conducting state due to a disturbance. While the concept can apply to many superconducting devices—transmission lines, generators, motors, etc.—it is most commonly considered in...
Cable-in-Conduit Conductors
Cable-in-Conduit Conductors (CICC) are a common form of superconducting cable used in large-scale applications. There are several varieties of CICCs, but they all consist of many small, stabilized superconducting wires contained within a conduit through which a coolant (typically supercritical He II) flows. Figure 1 shows the cross section of...
Bayonet Coupling
A bayonet coupling is a demountable joint that allows for quick and easy connection and disconnection of cryogenic components, including transfer lines, cryostats, liquefiers and refrigerators. Bayonets provide a number of advantages, chief among them the ability to connect and disconnect the bayonets while components they connect are still at...
Air Separation and Liquefaction
by Nils Tellier, PE, President, EPSIM Corporation (CSA CSM) nils@epsim.us All illustrations courtesy EPSIM Corporation Background History of Air Separation and Liquefaction This section builds on a rich history of methods to develop deep refrigeration and cryogenic liquefaction during the 19th Century. You are encouraged to read Cryo Central’s History...
Bose-Einstein Condensate
A Bose-Einstein condensate, first proposed in 1925 by Albert Einstein based on work done by Satyendra Nath Bose (the same Bose from whom the term boson is derived), is a super-cold state of matter in which almost all of the individual atoms have “condensed” down to the lowest possible quantum...
Cold Technology for Pest Control
While it does not reach temperatures cold enough to be called cryogenic, carbon dioxide snow is at the heart of a new way of dealing with unwanted pests. It utilizes a quick freezing process that takes advantage of the properties of carbon dioxide snow and has a number of benefits...
Cryogenic Finishing
The following 3 articles discuss the uses and procedures of various type of cryogenic finishing. 1) By Robin A. Rhodes, Cryogenic Institute of New England, Inc. rrhodes@nitrofreeze.com Cryogenic Deflashing is employed to remove undesired residual mold flash that remains on molded parts after they are removed or ejected from the...
Resistance to embrittlement at low temperatures
Could anyone advise me about resistance to embrittlement at low temperatures for the alloys in subject, i.e. does the CF10M perform like the CF8M in the same cryogenic service (-215F)? Amara Maafi Amara.Maafi@bg-group.com
Need help with temperature dependent model
I am a fourth-year student at New Zealand University. My name is Xu Ke. I have a project to generate a temperature dependent model for inductor, capacitor and diode by using PLECS. PLECS is software which acts as a toolbox for MATLAB. In my models, the temperature is very low,...
In what form is water available in LN2?
Does anybody know in what form water is available in LN2? There probably is a block of ice in the bottom of the tank. But as water comes in many shapes, I can imagine snow or crystals floating free in the LN2. When water is available in LN2, could small...
Separating gases using cryogenics
We are looking for some consulting engineers who understand how to separate gases using cryogenics. We have a new process which takes biomass and converts it to 5 gases and we need to separate these gases into their pure forms. Thanks for your help. Malcolm Draper Energy Research Group LLC...