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Comment Re:Icebergs float on glaciers (Score 2) 32

No, it does not form "one huge crystal". Nitrogen ices at these temperatures have little structural integrity. It was well known before we got to Pluto that if we saw any sort of relevant topography, we'd know immediately that it was from water ice, as nitrogen ices are so weak that they'd just flow slack over time.

Comment Re:Icebergs float on glaciers (Score 4, Informative) 32

Nitrogen ices at these temperatures, while crystalline, have rather low viscosity. If you put weight on them, they slowly diffuse around it until the object either sinks or is buoyantly balanced out. The latter happens in the case of water ice.

Also, it's worth noting that it's not pure nitrogen ices, it's a nitrogen-carbon monoxide-methane eutectic. Nitrogen is the most common component, however. Also, there are multiple crystal phases that can be taken, depending on the conditions. Nitrogen ices are most famous for having some rather "explosive" phase transitions between different states.

Comment Re: No transit costs. (Score 1) 105

Actually we used to have a curious form of economy for the longest time in many parts of Europe where key infrastructure was in the hands of the state while the rest of the economy worked out in a market economy. The net result was that there was a lot more competition for the consumer market because the playing field for the competitors was a lot more level.

In this example it would mean that the cables would be owned by a state controlled monopoly while the ISPs compete on equal footing by renting cable from the state monopoly and providing the ISP service to the customers. Much lower entrance cost into the market meant that a lot of small ISPs competed, allowing the price to drop. Then in their unending wisdom our regulators decided to "liberate" the market because that bad, bad state government made everything so terribly expensive due to all the red tape and bureaucracy that state monopolies entail.

Now, about 15 years after the monopoly fell, we have two major ISPs left, zero competition between the two (who curiously seem to divine whenever the competitor raises the price and matches it immediately), prices are up at the ceiling, bandwidths have been stagnant for a few years now, cables are congested because nobody invests in new infrastructure and the whole shit is going down the drain.

Thanks, free market!

Comment Re:Can we just make it legal to shoot executives? (Score 1) 105

I really say one should test that literally. How well does a golden parachute really work if you toss said manager out of the 50th floor? Inquisitive minds want to know! And let's be honest here, it sure ain't no loss if a CEO or two die in the process, we have far more than we need anyway.

Comment Re:Not a problem anymore (Score 1) 51

I can understand people engaging in telemarketing (because they're evil), but I don't get the point of making a call that you know ahead of time with absolute certainty is not going to end in a sale.

Fucked up incentives. Presumably because calls statistically leads to sales, someone was ordered to increase call volume. Presumably cold calling random people could get them in more trouble with the FTC or is against corporate policy, so to deliver on that they're making pointless calls. That the sell-through rate drops in proportion is muddled by competition, random variance, pricing policy etc. so the executives probably don't know it's happening. That kind of corporate dysfunction is quite common when employees don't have any incentive to run the actual business well, just according to the metrics.

Comment Pity there isn't a -1 ; Conspiracy Theory mod (Score 5, Insightful) 212

Slashdot needs ones. Seriously, for a community that claims to hate FUD, the OSS types sure like spreading it when it is about the "right" groups. If you actually care about what kinds of things the telemetry communicates back at various settings, the information is all out there for you. No, SSH data isn't one of them. However I am going to imagine you don't, and this is just crap you want to fling at "the bad guys" because you can.

Also a thought for you: Your OS, by definition, has access to anything any program on the system is doing. What would stop it from looking in at any 3rd party SSH server you ran, if you think it does that?

Comment Re:Go back in time (Score 1) 238

Pretty much. In retrospect, I thought Bitcoin was going to be one of those geek idea that just didn't pass beyond geek circles. I was considering getting in on it when it was like $1/BTC and like.. nah... not going to happen. In retrospect it's prety obvious but hey.. it's like the dotcom boom, even if you recognized it as a bubble you could make a lot of money riding it and cashing out at the right time. Bitcoin worked because it was first and everybody was rooting for some crypocurrency to be taken seriously. All the rest seem like "get rich quick" schemes where you keep some to yourself and try to make it valuable. I still use BTC but I have the feeling it has no "natural" level, it could be worth $10 or $100 or $1000 in a while. That doesn't stop it from being used in transactions, but as an investment it's pretty fucked up.

Comment Re:sunfire / in my stellerator / makes me... happy (Score 1) 97

Fast neutron cross scattering sections in the couple MeV range barely vary over more than the range of 1-10 barns

1-10 barns is, of course, by definition, an order of magnitude. There is a massive difference between 10 barns and 1 barn. Tenfold, to be precise. ;)

More to the point, you can't just combine all cross sections like that. The energy imparted from an elastic collision isn't the same as from an inelastic collsiion, which isn't the same as an (n, gamma), and so forth. Elastic collisions are particularly low energy, particularly the higher Z the target. Taking them out of the equation yields much greater differences between materials in the range of a couple MeV. The upper end of the neutron energies are "somewhat" similar (up to about one order of magnitude), but down below 6 or 7 MeV or so there's quite a few orders of magnitude difference.

Likewise, total cross sections have no bearing on the accumulation of impurities in the material. The particular cross sections are relevant not only in terms of reaction rate, but also what sort of impurities you tend to accumulate and what effect they have on the properties of the material. Which of course varies greatly depending on what exactly they are.

Integration of annealing cycles into blanket design is not brought up enough in some design studies, but is a consideration to help

It's not a side issue, it's a fundamental issue to the design of a material designed for high temperature operation under a high neutron flux.

Blanket design is extremely constrained by tritium breeder ratio to ensure more tritium is produced than used, which squeezes volume allowed to be used by coolant, ... but they have much lower neutron flux to worry about. Gen 4 reactor designs are in the 500-1000 C temperature range, exceeding in some cases what is thought reasonable for fusion blanket design. ... Blanket replacement is considerably more complex than fuel replacement in a fission reactor

Perhaps they've been heading in a different direction since I was last reading on the topic, but I was under the impression that a prime blanket material under consideration was FLiBe. Which operates in a temperature range of 459-1430C, and is its own coolant. That doesn't change what the first wall has to tolerate, but as for the blanket itself, you have no "structural properties" to maintain, and cooling is only limited by the speed that you can cycle it.

The last paper I read on the subject also suggested that for breeding purposes one needs not only beryllium (they were reporting really poor results with high-Z multipliers), but the optimum ratio (to my surprise) worked out to be significantly more beryllium than lithium. So building structural elements out of beryllium serves double purpose, you don't have the excuse of "I need to use steel because it's cheaper" - you need the beryllium either way. It's strong, low density, similar melting point to steel, but retains strength better with heat, and highly thermally conductive. Beryllium swelling from helium accumulation stops at 750C+ as helium release occurs. So pairing a beryllium first wall with a FLiBe-based blanket seems like a very appropriate option.

Please don't get me wrong, I'm not at all disputing the great amount of engineering work left to do. I'm just more optimistic that appropriate solutions will be found. Perhaps I'm just naive in that regard ;)

Comment Re:freedom (but only for those we like) (Score 2) 88

This. Exactly this.

The correct answer to people spouting bullshit is to call out their bullshit. Don't silence them by squelching them, silence them by showing them that they are wrong, that they are not the "vocal minority that dares to say what others only think", but that they are a loudmouth few who babble what everyone else knows is BULLSHIT.

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