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Comment Re:Man-portable supercooling? (Score 1) 298

They are not using helium as refrigerant, but as pressure transfer medium in a pulse tube for the Stirling cooler. It allows you to decouple the compressor from the cold finger and avoid the need of mechanical piston on the detector side. These detectors typically run between 40 and 80 K, too cold to use nitrogen as transfer gas, hence the use of helium. In any case, the operation range is far from the super cooled case.

Comment Re:Man-portable supercooling? (Score 1) 298

No they don't. Thermal imagers typically work around 50 K (based on HgCdTe sensors). This is easy to reach with a portable device, but isn't anywhere close to super-cooled. Higher performance thermal imagers may run at 3 to 4 K, cooled with liquid helium. There you are already far away from the portable solution, and again not even close to super-cooled.

To reach super cooled temperatures (we are speaking of mK, if not uK or nK), you'll need a truck to move the stuff around. Just the ultra high vacuum vessel and the turbo pumps, allowing you to reach vacuum better than in orbit at 200 km altitude, are enough... and you haven't started to cool yet.

Comment Re:Presentation of math (Score 3, Informative) 411

From TFA :
The reserves were downgraded by 96 percent, from 13.7 billion barrels estimated by a government-funded report in 2011, to just 600 million barrels, the EIA said.
Absolute values help put things into perspective.

Or do we need more perspective? For those who prefer the typical journalistic approach to understanding numbers, it's a reduction from 872'000 Olympic pools to just under 37'200 Olympic pools.

Comment Re:Where does 7 feet of water come from? (Score 4, Insightful) 323

Please stop with the half-assed facts. The average temperature of the coldest region of Antractica is -57C. That has nothing to do with the average temperature overall on the continent. What you wrote is just as stupid as saying nobody will get a heat stroke anytime soon in Pheonix; the average temperature in Vail is 11C (52F) after all.

Comment Re:Where does 7 feet of water come from? (Score 4, Insightful) 323

I find it very enjoyable, yet irritating, to see people take every single effect/cause independently, somehow analyse them (while actually having no clue at all what they are doing) and come to the conclusion they are too small to be related to a trend, while missing the obvious point that independent effect can be cumulativ. Worse, different effect can promote other and accelerate the trend. And they cook up a counter arguments (again while having no clue, even of the oders of magnitude) and propagate their ignorance to others ready to believe their pseudo scientific facts.

I really have to stand on the side of other posts I read here, stating that most people are simply not open minded or bright enough to understand the data and analyse it. A large part of this is to blame on education, but when basic logic and analytic skills fail (either due to intellectual capacity or to unwillingness to use those skills) I doupt even that would help.

Japan

New Battery Tech From Japan Could Supercharge EVs 81

joe5 writes "Many experts suggest that battery technology is really the key to the future of transportation. Its certainly the key to unlocking Tesla for even further growth. Today, a Japanese startup called Power Japan Plus unveiled a new battery chemistry that could significantly improve transportation batteries. In testing, the recycle-able cell has completed more than 3,000 charge/discharge cycles with virtually no performance degradation, meaning that it could conceivably last the lifetime of a car. They company won't yet provide too many details due to pending patents, and won't even say who its first customer is — but the chemistry requires 'specific and proprietary changes to the nanostructure of the carbon crystals.'"

Comment Re:Will never work.... (Score 1) 165

I do not believe the Aldi - Wallmart comparison is fair. And having lived over 30 years in Canada, I can confirm that there you also find BMW under carports. Not quite as much as here, but a lot...

For the reference, except a few models, BMW cars are expensive as well in Germany. The German tend to invest more on their cars (incl. maintenance). It's something important - which I can understand when you drive usually 150 - 180 km/h (93 - 112 mph) in normal trafic conditions .

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Top Ten Things Overheard At The ANSI C Draft Committee Meetings: (5) All right, who's the wiseguy who stuck this trigraph stuff in here?

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