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Comment Opposite Effect (Score 2) 63

Actually if radiation is aligned with a crystal lattice it interacts even more with the material and the radiation length (the distance travelled before 1/e of the particles interact on average) gets shorter. However this only happens if the radiation is aligned to within a few milli-radians of the symmetry axis of the crystal (and most metal you encounter is not a single crystal). I actually measured this effect as part of my PhD thesis for an application in the main particle physics experiment I was working on.

So no, this material will probably be no more effective than the same mass of gold in a thin, but solid, sheet. Radiation shielding with matter is a statistical affair and the fewer nuclei you have the less shielding you get. I'm also surprised that they suggest a use in jewelry since they also describe it as easily malleable, far more so than solid gold. Still it is interesting.

Comment Re:Hydro = from the sun (Score 1) 143

Direct solar may sound nice and work fine in small scale, but collectors would have to cover great areas to be effective

The total world energy consumption is somewhere around 100PWh/year. That's around 274TWh/day. The sunlight hitting the Earth is around 1kW/m^2, so 8kWh/m^2 assuming 8 hours of sunlight. If you assume 100% efficiency in conversion (totally impossible, but we'll start there and refine later), then that means that you need about 3.45E10 m^2 of land devoted to solar power. That's a square about 185km on each side. If you assume 10% efficiency (mass produced photovoltaics are 12-25% these days), then you need an area about 342000km^2, or about the area of Germany, to power the entire world. Now, given the efficiency of power distribution, you probably wouldn't want to put it all in one place, but you could easily fit solar panels enough that, even with transmission losses, you could power all of North America in Utah or Texas without anyone noticing. The difficulty is not the generation, it's the storage.

Comment Re:Or just make the diesels hybrids (Score 2) 173

And even the best public transport system generally isnt going to start and stop *exactly* where you need it, so there still is going to be *some* walking. Which some people with disabilities or health problems simply can't manage. And to achieve a good public transport system - with frequent stops, densely placed stops, relatively direct routes and affordable prices - is entirely dependent on population density far more than it is on "will". In places with high density, it's a relatively straightforward process to have a good public transport system. In places with moderate to low density, it can be difficult to nearly impossible. And weaknesses in public transport system are a viscious cycle: the less frequent the stops, the further spaced out they are, the longer the transit times, and the more expensive the rides - the fewer people will ride them. The fewer that ride the less frequent you have to have the stops, the further apart they need to be, the less direct the routes, and the less affordable the prices.

Comment Re:Disposable screens for disposable products? (Score 1) 198

This is likely by intent: Planned obsolescence can simply be implemented a lot better with OLED than with LCD. LCD was designed from the start as a long-lifetime technology. OELD is now correcting that mistake.

You're missing a crucial point. The lifetime of LCDs is more or less indefinite. The lifetime of the backlight however is very much finite, and the backlights (whether LED or cold cathode) fade and dim over time.

The problem is that making light emitting things that don't dim with age is really hard, because there are almost always unpleasant interactions between the various bits. Like gas can slowly leak in/out of gas discharge things. Electromigration occurs, and so on and so forth.

The light source with the best aging properties is sulphur lamps because the sulphur gas is (a) self healing (unlike semiconductor crystals) and (b) has no metal electrodes anywhere near it. Of course, the magnetron used to drive the lamp ages...

But yeah, OLED age and LCDs don't, but LCD backlights do.

Comment Re:Err, petrol is currently cheaper that diesel (Score 1) 173

van thats been thrashed all its life it'll start belching black shit out of its exhaust on acceleration (which is barely tested in the MOT)

I always assumed white van man considered this a feature, not a bug and paid their dodgy mate to tune it up to be just-so when it comes to belching black smoke. It's like the thick yet incredibly uniform layer of grime which is so good for writing witty slogans on. I have a working theory that it's actually impossible to curate that by natural means and there's a small chain of shops operating from grimy railway arches which apply it for a small fee.

It's the only explanation that makes sense.

Comment Re:systemD (Score 3, Interesting) 98

Can someone explain why ALL THE MAJOR DISTROS have switched to systemd, when all I've seen is universal hate for it?

The hate isn't universal.

It's certainly easier for distribution integrators than the old RC scripts. Also, there has been considerable external pressure because some of the major packages like Gnome more or less depended on systemd, so not having it meant no Gnone which was a showstopper. Actually you can now run Gnome without systemd but for a while that wasn't possible.

Another reason for the hate is that there are a lot of awfully obnoxious systemd fanbois out there who make claims like:
* You hate change (literally ad-homenim, attaxking the person not the message)
* Making claims about things that are only possible with systemd that demonstrably are not (I debunked a bunch of these in the last thread)

There's a lot of FUD on both sides, and frankly after the PulseAudio debacle, a lot of people have a deep distrust of Lennart Pottering (well justified IMO), and are incredibly leery of making the core of a Linux system depend on code written by a cowboy coder who doesn't seem to care about stability or quality.

Comment Re:Does he have the data to support his "beliefs"? (Score 1) 173

Well, there is all that smog in London that is mainly caused by diesel by-products. Last year practically the entire country was under a smog alert at one point.

Yes but he doesn't propose banning the main source of diesel polution: Heavy vehicles. He is only proposing banning an insignificant source of diesel polution, the source that already has the strictest rules and best filters.

Comment Supernova Required (Score 3, Interesting) 143

Even nuclear fission power comes from heavy elements fused at the center of the sun and spat out during an early nova outburst.

Actually a supernova is required to produce the heavy, fissionable elements. Based on the ratio of Uranium isotopes the one that gave us our heavy element occured about 6 billion years ago or about 1-1.5 billion years before the solar system and Earth formed.

The sun is powered by nuclear fusion which can only create elements up to iron-56 after which you have to put energy into the process to make larger nuclei. In stars ~4-5+ times larger than our sun this comes from the sudden gravitational collapse of the core when it has burnt all the way up to iron. The result is a supernova: the core collapses into a neutron star and the resultant release in gravitational potential power both the explosion as well as the production of the heavy elements beyond iron.

In fact if you really want to escape solar power the only option is nuclear fusion. However this could be regarded as a fossil fuel since you are using energy 'fossilized' by the Big Bang and is not renewable...but then there is no such thing as renewable energy if you take the really long term view.

Comment Re:Hydro FTW (Score 1) 143

If hydro is available, why not use it? Nothing is perfect by any means, but once the dam is constructed, hydro is a relatively inexpensive source of constant, high quality electricity 24/7. A good example of this would be Paraguay/Brazil's Itaipu Dam.

If it were available, I'd definitely go hydro. However, in a lot of areas, it definitely isn't going to be possible.

Most likely, a data center would probably have to use a mixture of sources. Solar would definitely help take the edge off peak energy consumption (both in the energy machines used, as well as the energy used by the HVAC system to keep them cool.) Next to that, a wind farm (although not many areas in the US are good for this.)

If the data center is in a completely rural area, what might be one source, assuming the absolute stark terror of nuclear abates for a bit, using an on-premises thorium reactor (LFTR/MSR as a type as it can use more generated energy, as per the Transatomic ads... take them with a grain of salt) comes to mind. This would not just provide base energy for the data center, but also be an asset to the electric grid.

Of course, if fusion power becomes available, all the debate about energy becomes moot.

No problem is so formidable that you can't just walk away from it. -- C. Schulz