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Comment: Re:Yes, it's a conflict of interest. (Score 1) 437

by hankwang (#49104557) Attached to: How One Climate-Change Skeptic Has Profited From Corporate Interests

Having a conflict of interest is understandable; hiding a conflict of interest is problematic.

The strange thing is that his management (Alcock and Kress) is claiming that they were unaware of his funding. The research grants pass through the accounting department of the institute, right? Large sums of money deposited onto or withdrawn from the institute's bank account need to have proper paperwork in place and be signed off by the management? His management must have been actively looking the other way.

Comment: Re:That's unpossible. (Score 2) 212

by WolfWithoutAClause (#49101503) Attached to: The Best, and Worst, Places To Drive Your Electric Car

> So electric cars have electric heaters; I had not thought about that aspect before. That would be a considerable inefficiency;

To some extent. The main problem is that it flattens the battery more quickly and impacts range in winter time, the actual cost of the heater for an hour or two is generally relatively trivial compared to the other costs of running the car.

The newer electric cars have much less of an issue though. Instead of using electric heaters they run the air conditioner in reverse (it's an 'air source heat pump' in fact) and most of the heat energy then comes from the external environment rather than resistive heating. The heat pump uses about 1/3 of the power.

Comment: Etching does the same thing (Score 2) 133

by hankwang (#49099639) Attached to: Crystal Pattern Matching Recovers Obliterated Serial Numbers From Metal

It has been possible for decades to recover serial numbers by chemical etching, which is sensitive to changes in the crystal structure. All you need is a polishing implement and a bottle of etching gel. What is the added value of this EBSD technique? I can see a big disadvantage: you need equipment (a scanning electron microscope) worth a few hundred kEUR and the object with the erased serial number needs to fit into the vacuum chamber of said equipment.

The article mentions that etching techniques don't always work, but they don't state that their technique does work on samples for which the etching method doesn't work...

Comment: Re:Nope, still a story. :) (Score 1) 215

by WolfWithoutAClause (#49088789) Attached to: Japan Now Has More Car Charging Points Than Gas Stations

Nope, even the worst case is not a deal breaker for most people.

The thing is, most people don't empty the battery most days. A lot of people do like 20 miles a day, so in practice, even with a conventional socket, the car is full again each morning; even on 110 volts.

If you have a 240 volt socket, which are very, very widely available, it's even less of an issue.

And the extra cost to install a higher current charging point is very low. Where I live most premises have a 30 amp, 240 volt circuit already for their electric cookers. That's about 6kW, and the Nissan Leaf has a 24kWh battery; it can do an 80% charge in about 4 hours.

Comment: Re:so (Score 1) 220

by WolfWithoutAClause (#49078227) Attached to: Obama Says He's 'A Strong Believer In Strong Encryption'

In most cases crypto is like having the worlds best lock on your door; the people that want to get in just jimmy the window instead.

The phone thing could certainly happen in theory, but in practice the NSA may have already installed a backdoor or found an accidental backdoor that was due to a bug. And they would probably copy the flashdrive in the phone and analyse it later, possibly on a supercomputer if they're really keen; a lot of commercial crypto is deliberately weak so they can crack it that way if they really have to.

Comment: Re:You're both right, and both wrong. (Score 1) 311

by hankwang (#49068525) Attached to: Nuclear Plant Taken Down In Anticipation of Snowstorm

What makes you both partially correct is that there isn't a delay in fission, but a delay in neutron release.

From reading the linked Wikipedia page, I get that the delayed neutrons are responsible for 0.6% of all neutrons emitted from fission, and most of them with half-life times between 2 and 20 seconds. While this makes for some nice control bandwidth (you can afford to be 0.6% off with the control rods without getting an instantaneous nuclear explosion), I don't see how these delayed neutrons can be responsible for the majority of the 7% decay heat.

Comment: Re:Nuclear plants don't like sudden shutdowns (Score 2) 311

by hankwang (#49064637) Attached to: Nuclear Plant Taken Down In Anticipation of Snowstorm

"Normally there is some time between neutron capture and actual nuclear fission (I have heard a figure of 15 minutes)."

The fact that you can detonate a nuclear bomb by bringing together two subcritical pieces of U-235 shows that this can't be true.

In a nuclear reactor, 7% of the heat output is from the decay of the fission products (alpha and beta decay). This 7% will continue to be generated regardless of control rods or neutron absorbers. It will last hours to weeks, depending on where you put the threshold for "finished". Remember Fukushima: it became a disaster when the water circulation backup pumps failed 12 hours after the reactor shutdown.

Comment: Re:Nope, still a story. :) (Score 1) 215

by WolfWithoutAClause (#49060363) Attached to: Japan Now Has More Car Charging Points Than Gas Stations

A charge station at home is just a wall socket- you can literally just plug your car into the wall and charge it already.

So EVERY house that is on the grid is already EV infrastructure.

The numbers show that the existing grid can (with some exceptions) handle EV charging (which would and should be mostly at night where the grid is underutilised anyway.)

Comment: Re:This is great! (Score 1) 215

by WolfWithoutAClause (#49060273) Attached to: Japan Now Has More Car Charging Points Than Gas Stations

Actually, the electricity can come from renewables.

Some places have hydroelectricity, nuff said.

Also, wind power and solar is available nearly everywhere, and electric cars do great on that; they don't normally need to charge up everyday, and when there's a glut of wind or solar they can suck it down; and (if you have the right equipment) even sell it back again.

Comment: Re:The Greater Danger (Score 1) 180

by hankwang (#49030321) Attached to: US Gov't To Withdraw Food Warnings About Dietary Cholesterol

"until the discovery of the chirality (and chirality affects a lot of things) of saturated fats, they probably got mixed together (they're still saturated fats, after all) and the original problem was because of the hidden trans- version."

I think you are mixing up things. Trans and cis fats are both unsaturated fats, with double bonds. Saturated fatty acids have no chirality. (Well... Triglycerides are technically often chiral (the middle carbon atom of the glycerol backbone), but that's not relevant for the cis/trans/saturated discussion.)

It is not best to swap horses while crossing the river. -- Abraham Lincoln

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