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Old 11-11-2007, 00:00   #31
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I too am of the opinion that the more you learn, the more you realize how little you know until you get to a point that you know everything about nothing. LOL. I was working with main frames and minis before the advent of the PC. My first reactions to IBM's PC at the time it came out was that it was only good for playing games and writing letters, they were a fad that would not last. ( I was young and cocky) Now my laptop is my most useful tool. To dismiss the idea of magnetic refridgerators in boats is premature. A great many science fiction ideas of the past are a reality of today.
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Old 11-11-2007, 00:23   #32
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Actually, the magnetic fridge is theoretically sound. What I thought was piss poor was the reporting that claimed the fridge used no electricity.

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Old 11-11-2007, 05:40   #33
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From the Wikipedia article on this subject

Magnetic refrigeration - Wikipedia, the free encyclopedia

".....The magnetocaloric refrigeration system is composed of pumps, electric motors, secondary fluids, heat exchangers of different types, magnets and magnetic materials. These processes are greatly affected by irreversibilities and should be adequately considered. Appliances using this method could have a smaller environmental impact if the method is perfected and replaces hydrofluorocarbon (HFCs) refrigerators (some refrigerators still use HFCs which have considerable greenhouse effect). At present, however, the superconducting magnets that are used in the process have to themselves be cooled down to the temperature of liquid nitrogen, or with even colder, and relatively expensive, liquid helium. Considering these fluids have boiling points of 77.36 K and 4.22 K respectively, the technology is clearly not cost-efficient and efficient for home appliances, but for experimental, laboratorial, and industrial use only."
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Old 11-11-2007, 07:08   #34
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From the U.S. Department of Energy's Argonne National Laboratory and Ames National Laboratory.

Scientists at the DOE’s Ames Laboratory have developed a highly efficient magnetocaloric material that makes magnetic refrigeration technology efficient enough to cheaply produce liquid hydrogen, very likely one of the first major commercial uses of magnetic refrigerators.
Gschneidner and Pecharsky found that they could tune the operating temperature (gradually lower the Curie point) of a gadolinium silicide compound (Gd5Si4) by substituting germanium (Ge) for silicon. This resulted in a new compound, Gd5Si2Ge2, which has a magnetocaloric effect about twice as large as gadolinium alone.
Additional work has revealed that Gd5Si2Ge2 is one of a family of compounds that exhibits a giant magnetocaloric effect and whose ordering temperature can be tuned from 30 Kelvin (-405.4 F) to near room temperature (290 K or 62.6 F) by adjusting the ratio of silicon to germanium.
The new coolants may eliminate the need for the superconducting magnets associated with earlier cryocoolers.
Magnetic refrigeration


Scientists carrying out X-ray experimentation at the Advanced Photon Source at Argonne — the nation's most powerful source of X-rays for research — are learning new information about magnetocaloric materials that have potential for environmentally friendly magnetic refrigeration systems.
The magnetocaloric effect – a change in temperature accompanying a change in a material's magnetization – is largest near a material's intrinsic magnetic ordering temperature. In the case of rare-earth gadolinium, this ordering occurs near room temperature and results in a temperature increase of 3-4 K/per Tesla when a magnetic field is applied, making gadolinium the current material of choice for magnetic refrigeration near room temperature.
The prospects for a viable magnetic refrigeration technology recently became brighter with the report of a giant magnetocaloric effect in gadolinium-silicon-germanium alloys. The addition of non-magnetic silicon and germanium ions brings about a giant entropy change when germanium-silicon chemical bonds connecting the magnetism-carrying gadolinium ions are quickly formed or broken, respectively, by the application or removal of a magnetic field. As an added bonus, the magnetic ordering temperature can be tuned by changing the ratio or germanium to silicon.

Giant magnetocaloric materials could lead to new refrigeration technologies
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Old 11-11-2007, 09:49   #35
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Quote:
Originally Posted by Lancerbye View Post
A great many science fiction ideas of the past are a reality of today.
This is what I believe the human race does collectively, apparently without conscious thought. As in; What directs the ant hill's activities?

We dream of something, call it science fiction (todays term) and then work toward making it a reality.

It happens all the time.

It will continue to happen.

Many humans believe in God (interpret that word/name however you wish) but what they actually do is work toward being God by making (creating) things. They also want to control the things they make.

Why else would we be working on robots that are modeled after the human form if not to create something in our self image.

In that sense we are quite shallow I think.

What that has to do with magnetic refrigeration is a little far off but it does bring chills to me sometimes when I think about it.
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Old 11-11-2007, 10:33   #36
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Quote:
What I thought was piss poor was the reporting that claimed the fridge used no electricity.
Absolutely, We woudl nto have had the depth of argu....I mean...depth of discussion if the report was a little less "headline seeking".
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Old 11-11-2007, 10:38   #37
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I guess we can check back on this in about 20 years...
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Old 11-11-2007, 11:07   #38
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It's called marketing sensationalism, in attempts to suck someone in to read what they write. It worked and the reporter got paid. Since when is reporting accurate? TIC
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