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Comment: Re:In this house we obey the laws of thermodynamic (Score 2) 140

by Rei (#48476923) Attached to: Scientists Develop "Paint" To Help Cool the Planet

It's not the ambient temperature of air that's key here, it's the ambient temperature of space, which is about 2,7K.

All objects are constantly radiating energy and receiving energy back from other things that are radiating. When two objects in radiative exchange are roughly the same temperature, this balances out. But when one is hotter than the other, the hotter one loses more energy than it takes in, and vice versa. And it's not just a little difference - radiative heat loss is proportional to the absolute temperature to the fourth power, that's a pretty big exponent. So when you're exchanging energy with space, which is so cold that it takes very sensitive instruments to be able to measure *anything*, well, that heat is simply lost.

You can see this effect for yourself by noting how cloudy nights are usually warmer than clear nights. Clouds are cold, but they're not as cold as space!

The effect of the combination of radiation, absorption, and reflection, with different band peaks for each phenomenon, manifests itself in atmospheres as a greenhouse effect (positive or negative) versus the radiative equilibrium temperature.

Comment: Re:In this house we obey the laws of thermodynamic (Score 1) 140

by Rei (#48476869) Attached to: Scientists Develop "Paint" To Help Cool the Planet

This "modulation" happens all the time, few things in this universe are true blackbodies, most prefer to radiate in specific bands. They're apparently using a material that tends to radiate only on one narrow band at regular earth temperatures.

Not sure how much benefit this provides to the building owner, to the point that they'd be willing to cover their building in hafnium-and-silver coated panels, rather than just white paint...

Comment: Re: haven't been following... (Score 1) 179

by Rei (#48476295) Attached to: Behind Apple's Sapphire Screen Debacle

Does anyone actually have problems with scratching of the latest generations of gorilla glass? I've had my Xperia Z2 for over half a year and because it has a glass back as well as front it makes it less risky to try scratch tests, so I've done it a number of times and let other people try to scratch it, and nobody has ever succeeded. I'm sure if you put a diamond to it you'd scratch it, but short of that, I can't see why more scratch resistance is needed.

Now, *crack* resistance, they could use good improvements in that. : But from reports the sapphire wasn't that crack resistant.

Comment: Re:Alive and gobbling (Score 1) 112

by Rei (#48473053) Attached to: I prefer my turkey ...

Surprised you haven't gotten any "but animals eat meat!" comments.

Animals also commit petty murder and mass rape. I like to think that we have the intelligence to choose to not have to imitate the behavior of other animals and decide our own path. And fortunately, we have a digestive system which allows us to make that choice when it comes to our diet.

Comment: Re:What's with turkey anyway (Score 1) 112

by Rei (#48473045) Attached to: I prefer my turkey ...

Swans can literally kill people - a guy died just a couple years ago when swans attacked his boat and then kept attacking him while he tried to swim to shore, until he drowned. More common though are things like bruises (up to and including black eyes), scratches, and skin-puncturing bites. A google image search for swan attack shows how they don't mess around when they feel threatene (there's even pictures of one attacking a full-grown horse)

Comment: Re:What's with turkey anyway (Score 2) 112

by Rei (#48473019) Attached to: I prefer my turkey ...

It's not all that distant of a relative of chickens, actually - it's in the same family (but a different subfamily). It's kind of wierd that one family (Phasianidae) has almost all of the commonly consumed poultry - chicken, turkey, grouse, quail, pheasant, peafowl, guineafowl, etc. Go up to the order level and you find more (mostly regionally popular) game fowl, like ptarmigan. And once you hit the superorder level, you get the water fowl like ducks, geese, and swans. I can't even think of any other poultry species. There's lots of Aves clades, subclasses, and infraclasses, but apparently the species that people find make good eating are rather clustered together.

Comment: Re:Niche energy (Score 1) 89

by Rei (#48471461) Attached to: WaveNET – the Floating, Flexible Wave Energy Generator

A lot of companies are involved in a lot of renewables tech research. That doesn't mean that any particular one is going to be profitable. The vast majority are going to be big failures.

Wave power's track record so far has been subpar to say the least. And looking at their diagrams, I can't imagine that they're not headed straight for the same fate. Even if we assume that their numbers aren't overly optimistic, their design looks like it would involve several times more steel per nameplate capacity than a wind turbine tower. And they're operating in a much harsher environment. No rotors, but they're dealing with major hydraulic pumping instead. It just doesn't look like a winner to me.

If it was my job to have a go at wave power, I can't imagine going for anything involving large amounts of structural steel or hydraulic pumping; I'd keep it simple and just go for a grid of cables (potentially a high tensile strength UV-resistant plastic), anchored at the edges to keep tension up across the whole grid, with the only slack available involving the grid pulling on regularly spaced springloaded reels (the rotation thereof generating electricity), with any combination of floats, drag chutes and weighs/anchors to cause the needed tug from the movement of water. No pumps, no hydraulic fluid, no large compressive-loaded structures, just a tensile structure that would be (proportionally) lightweight and easy to deploy.

But hey, it's not my industry ;)

Comment: Re:It boils down to energy storage costs (Score 1) 630

by Rei (#48466617) Attached to: Two Google Engineers Say Renewables Can't Cure Climate Change

And from their numbers, it doesn't look like they're using a reasonable estimate for Chernobyl. There've been some ridiculous estimates out there from both sides, ranging from "only the couple dozen who died directly" to "millions".

One can look at the approximately 10% higher mortality rate within the exclusion zone to get a rough sense of the consequences, but without knowing demographics, it's hard to draw conclusions from that. Probably the best (peer-reviewed) analysis I've seen compared doses with the US military's mortality data from exposure to the nuclear bombings in Japan. You get a figure of about 4000 extra deaths with moderate confidence and 5000 with low confidence (the error bars can be in either direction). So very rough ballpark of 9k deaths, plus the first responders and the like.

Yes, even when you include things like that, nuclear's death toll is lower than coal, no question. But it's not as low as they make it out to be. Their bias is obvious.

The deadliest nuclear accident, Chernobyl, was caused by defense department testing.

Yep, nuclear disasters can happen from both man and nature. That's hardly a comfort. Will "defense department testing" cause the next major nuclear accident? Very unlikely. But there almost certainly will be a "next major nuclear accident" - we just don't know what form it will take. It's a "known unknown".

Whereas Fukushima was all user error?

No. But if you're going to include "dam-induced casualties from storms", then you should include "people spared from storms by dams" also, it's only fair. And thus hydro's death count would be strongly negative.

Perhaps it is possible to offset renewables in such a way that they can provide 90% of our power needs, but no one has ever done it.

Speak for yourself. I live in Iceland where over 99,9% of the grid is renewable (primarily hydro). 99,9% renewable baseload at that. There's even serious preliminary work looking into building the world's longest submarine power cable to export power to the UK.

Again, not saying that hydro is my preference - I've stated my preference above. Just pointing out that your claim is wrong.

(Concerning the power cable: I'd support if A) they'd only be adding geo plants and wind to meet the extra power need, and B) the government would tax the power sales to the point where the cable makes just barely enough profit to economically justify its existence... but I'm sure that A) they'd probably just dam up the highlands some more - who gives a rat's arse that we have some of the world's most abundant and cheap geo and wind power that could easily compete on the European market, hydro gives a tiny bit more profit margin!; and B) the government would hardly push back at all on power export royalties because, hey, JOBS! Jobs damming up the highlands!)

Comment: Re:Next step - Semiconductors (Score 4, Funny) 69

by Rei (#48466211) Attached to: ISS's 3-D Printer Creates Its First Object In Space

Close, but your syllable count is a bit off. Something like this would work:

fuck ink jet printers
fuck all those fucking printers
i fucking hate them

Technically, though, you're supposed to have a connection with nature for it to be proper haiku. So maybe something more like

ink jet printer rests
at the bottom of the bog
piece of shit printer

Comment: Re:Next step - Semiconductors (Score 4, Interesting) 69

by Rei (#48466155) Attached to: ISS's 3-D Printer Creates Its First Object In Space

They did. But first off, to correct the GP: Concrete does not release CO2. It absorbs CO2 (slowly taking back the carbon that was released during the cement's creation). So this messed up their balance equation. Metabolism was supposed to consume O2 and make CO2, while photosynthesis was supposed to consume CO2 and make O2. But with the concrete locking up the CO2, the output of metabolism was being locked up and not being converted back to O2, so the O2 levels declined.

It's a simple oversight, but one that we're very lucky was made on Earth and not on, say, Mars. More foresight could have caught it, but there's always something that slips through the cracks. A number of other issues showed themselves, such as unexpected condensation adding rain to areas supposed to be rainless, less light than anticipated making it into the habitat, certain inspect species proving incompatible with the environment while others proving to be pests, so and so forth. They also had big problems with wild fluctuations in CO2 by time of day and season - they didn't have a massive amount of atmosphere to buffer it, so levels collapsed during the day and shot up at night. A lot of people complained that the project wasn't focused enough on the science, but I think they learned an awful lot of important things that could prove critical if ever trying to grow crops on another planet.

(The psychological aspects and how the crew split into two bitterly divided factions is also a real cautionary tale)

So anyway: after the first Biosphere 2 experiment was terminated, they sealed the concrete and started another one. But the second experiment was more doomed by politics than anything else. The on-site management was foreceably evicted by federal marshals. Former biosphere members broke into the facility so that the people inside could know what was going on outside (in the process, ruining the sealed environment). And then a couple months later the management company was dissolved. Altogether the second mission lasted less than half a year. It was a total disaster.

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