1) Most pirate copies of windows are "Corporate" keys. They don't require activation.
2) My experience is that, regardless of how many times you have activated a key, as long as you don't say "Because I'm a dirty pirate" when the phone-drone asks why you need it reactivating again it's all good.
Basically this appears as if it's going to piss off a whole bunch of people for no good reason.
The point is that neutrons are tricky beasts to measure-in this experiment doubly so because you have a large source of neuts present to initialise the bubbles. The only way that you can be sure that the neuts you're detecting are a result of a fusion reaction at the same time as the bubble collapse is if you detect them at precisely the right instant of time. They didn't. This would suggest that, whatever the reason for excess neutrons may be, it's not bubble fusion. This is in fact excellent science. The goal is always to be sure to measure the effect that you think you're measuring.
Yes- they gain a percentage of the final bid price.
In your example they would gain only a few cents but this would mount up to a substantial amount of money quickly given the number of eBay transactions.
Yep. There you've summed up why you're all screwed over there in the once great US of A. Over here in the UK I have watched with amazement as your country has been stolen from you by a bunch of money grabbing scum. We've got it pretty bad with old "Teflon Tony" but at least he seems to be acting in the interests of the general population some of the time.
I recommend that you all begin putting pressure on congressmen and exercise your right to peaceful protest before they take that away too.
Plutonium's produced by bombarding U238 with neutrons- this produces 239 U, which beta decays to 239 Np (neptunium). The neptunium isotope again beta decays to 239 Pu. To produce more than miniscule amounts of Pu you need a very high neutron flux- the only real, practical way of getting this is a fission reactor. Essentially this limits plutonium production to groups (countries) with a developed nuclear industry. This is somewhat simplified as you also get another isotope, 240 Pu, if you screw up the exposure times. This isotope decays via spontaneus fission and you want to minimise the percentage present in your bomb material.
Again I think that the only people anyone in a position to provide the fuel would be able to provide a complete bomb.
I disagree that the impact on society would be higher for a dirty bomb explosion than the trade center attacks. There would have to be a short term, small area evacuation and inevatably there would be a panic. However the idea that such a bomb would render a significant area unihabitable in the long term is just nonsense.
Basically, no. Centrifuges are indeed the method of seperation but it's a little bit more tricky than that. The two forms of uranium are so close in atomic mass (235 and 238) that this process is a real bitch. Plus it's toxic and you can't have too much of it in one place or you kick off a chain reaction and everyone dies of radiation poisoning.
Also, another point, both forms of Uranium are "fissible" - they differ in their reaction cross-sections for neuts. U235 for high energy, U238 for low energy. In other words for reactions with thermal neuts (i.e. reactor cores) you want 238 with a bit of 235. This is why reactor fuel is high in 238 and bomb fuel is high in 235 (typically 80%+).
So there's two ways you can go about building your fission bomb.
"Gun type" - This was the way they built the Hiroshima bomb. Two bits of fissile material banged into each other using high explosive to form a critical mass. This only works with Uranium as plutonium bombs built using this method would "fizzle"- chain reaction kicks off before the core go's critical. Nobody makes bombs like this because of the inherent danger of accidental detonation- they could concievably go off in a crash or fire. The advantage of this type of bomb is that it's easy to make and you can be pretty sure it will go off ok (which is why they chose it for Little Boy).
"Implosion type"- a sphere of fissile material with a hollow in the middle is crushed into a critical mass using explosive lenses. This is much more efficient than the gun type due to the increased density and the detonation speed. Getting the high explosive lenses right is a real bastard though. The literatures pretty light on the explosive details strangely enough.
So, basically, your common or garden "building it in his cave" terrorist stereotype is going to have to go for the gun type. All the cross section and neutron transport data's available, you only need some world war II tech high explosives and machining ability and you're done. Thing is you're limited to highly enriched uranium.
Ok, so nobody's serious suggesting that any non-governmental group is enriching their own uranium (at least I hope not). So they have to aquire very high U235 content uranium from somewhere. Where's the only place you find this? Bombs. Basically I reckon that anyone in a position to sell terrorists material for a bomb is in a position to sell them one pre-assembled.
Around 5% of shipping containers imported into the UK go through a full customs inspection. I think it's similar in the US. Why would they bother launching one when they could drive it to their target with ease?
The destruction caused would only really be the same as the equivalant convential bomb without the radioactive content. The only real consequences are a result of a combination of peoples general ignorance of all things nuclear and the fact that it's a useful tool for governments to keep us good and scared. In other words: panic and a reluctance to return to the blast area. The only exception is if the forces of "them" manage to aquire some real nasty stuff- particulate strontium 90 or some cesium 137. These would work (kinda) as a real area denial weapon but still wouldn't cause mass casualties.
A 'proper' fission bomb on the other hand is a different matter. Even a small one would wipe out a good portion of a major city and kill tens of thousands of people plus.
Actually, I don't think actually handling it outside the body is that much of a big deal. It's only regarded as such nasty stuff because if you ingest some it winds up in your bone marrow.
Ok, world blows up, bits flying, "don't panic", "coming soon yadda yadda". Ends. I see people talking about what the cast look like and stuff- am I missing the correct trailer?
They only reference one study, published in "Home Power" magazine, written by two people who appear to work for solar panel manufacturers (I think its this one: http://www.ecotopia.com/apollo2/knapp/PVEPBTPaper. pdf)
Anyone got a better source? I admit my info's a bit out of date- I had a lecture a couple of years ago from one of materials science prof's and that's about it. Can't seem to find anything definative on google - seems to be a lot of debate about how you make the calculations. Chiefly that many pro solar studies ignore the fact that you need a bunch of big, deep cycle batteries (with a life time of only a couple of years) to make a practical solar system. Many of the anti-solar people tend to use older silicon refining energy figures though.
Bah. Everything fun is at least a little bit dangerous. Nobody's making you build one and you're fairly unlikely to come to harm because some "wacko" (to use your terminology) has knocked up a Tesla coil in his garage.
Same go's for playing with old microwave ovens. Just for the record, by the way, even if he screws up royally he's not going to get cancer from his microwave- non-ionising radiation you see. He could cook himself though- that'd probably suck.
I think this kind of nanny "but you might hurt yourself" attitude is going to harm future science education. Already it's at the point where you can no longer do a bunch of demonstration experiments in the classroom. Big sparking things, stuff exploding- that's what provided the hook to get me into physics.
Don't forget the really big problem with solar: energy returned for energy invested. A big block of purified semi conductor takes a lot of energy to make. It means you have to run your solar cells for a very, very long time before your net energy gain is positive.
I always thought that explosion was a cover for a underground nuclear test. You see, the only way to be really, really sure your nuke design works as expected is to set one off. You can't do this above ground, openly because people would get upset (i.e. the US, possibly even china). It is possible to set off a nuke underground in a chamber packed with charcoal to absorb a lot of the energy and still get meaningful data. BUT this still produces a fairly characteristic seismic signature. You could cover this up with a BIG conventional explosion at the same time in approximately the same area.,p> How's that for a nice conspiracy theory?
Asshat who happens to have a blog gets job at google. For two weeks. Then they fire him.
I mean, really, if everyone who got fired for being bad at their job and talking crap online made the front page of/. there wouldn't even be enough space for the important stories about "battery life extenders". (BatMax: the worst slashdot 'news' ever?)
I thought the point was that everybody got it in the ass, regardless of skill.
Don't knock the geology majors either. After all, someone has to find us all that oil. Too boring a job for us physicists and engineers- leave it to the rock monkeys.
Re:Wait a sec, this story isn't about "dark matter
on
Dark Matter Discovered
·
· Score: 2, Interesting
No. RTFA.
That's because intergalactic baryons not only fill a gap in scientists' understanding of the universe, but they may also lead to a better understanding of "dark matter," a mysterious and unseen form of matter that has so far only been detected by the gravitational pull it exerts on other bodies in the universe.
"If we are right, each single one of these filaments is connected to a cloud of dark matter," said Nicastro. "If there wasn't dark matter there, or something with strong gravity that pulled on the matter in these filaments, we wouldn't have galaxies or filaments." Rather, the baryons would be pulled into galaxies and the galaxies into each other.
Basically speaking it could be that the reason this big cloud of baryons hasn't collapsed into stars is because of dark matter.
All through high school I had root access thanks to a fake login screen program I built. It was easy- just boot the computer from a floppy and install my little proggy. Only ever used it to dick around installing games and stuff.
When I got to uni I tried the same thing. Installed a different version on a lab PC next to a printer that I had occasionally seen an admin login to. Came back the next day, my program was gone and my user account was frozen with a "Please contact system administrator" message. Turned out that the sys admin in the physics department was a hardcore old unix bod who'd been an admin since the days you programmed with punch cards. He had seen it all. The computers allowed a boot from floppy but logged it and alerted him in real time. He watched me install my program on the CCTV, then watched me log into another computer so he had my username. Dude was in a different league from my school admin!
Luckily Physics had it's own rules for what happened if you got caught "hacking". First time you only got a slap on the wrist and had the rules carefully explained, 2nd time was where the restricted computer use came in.
Slashdot Mirror
1) Most pirate copies of windows are "Corporate" keys. They don't require activation.
2) My experience is that, regardless of how many times you have activated a key, as long as you don't say "Because I'm a dirty pirate" when the phone-drone asks why you need it reactivating again it's all good.
Basically this appears as if it's going to piss off a whole bunch of people for no good reason.
The point is that neutrons are tricky beasts to measure-in this experiment doubly so because you have a large source of neuts present to initialise the bubbles. The only way that you can be sure that the neuts you're detecting are a result of a fusion reaction at the same time as the bubble collapse is if you detect them at precisely the right instant of time. They didn't. This would suggest that, whatever the reason for excess neutrons may be, it's not bubble fusion. This is in fact excellent science. The goal is always to be sure to measure the effect that you think you're measuring.
In your example they would gain only a few cents but this would mount up to a substantial amount of money quickly given the number of eBay transactions.
I recommend that you all begin putting pressure on congressmen and exercise your right to peaceful protest before they take that away too.
Again I think that the only people anyone in a position to provide the fuel would be able to provide a complete bomb.
I disagree that the impact on society would be higher for a dirty bomb explosion than the trade center attacks. There would have to be a short term, small area evacuation and inevatably there would be a panic. However the idea that such a bomb would render a significant area unihabitable in the long term is just nonsense.
Also, another point, both forms of Uranium are "fissible" - they differ in their reaction cross-sections for neuts. U235 for high energy, U238 for low energy. In other words for reactions with thermal neuts (i.e. reactor cores) you want 238 with a bit of 235. This is why reactor fuel is high in 238 and bomb fuel is high in 235 (typically 80%+).
"Gun type" - This was the way they built the Hiroshima bomb. Two bits of fissile material banged into each other using high explosive to form a critical mass. This only works with Uranium as plutonium bombs built using this method would "fizzle"- chain reaction kicks off before the core go's critical. Nobody makes bombs like this because of the inherent danger of accidental detonation- they could concievably go off in a crash or fire. The advantage of this type of bomb is that it's easy to make and you can be pretty sure it will go off ok (which is why they chose it for Little Boy).
"Implosion type"- a sphere of fissile material with a hollow in the middle is crushed into a critical mass using explosive lenses. This is much more efficient than the gun type due to the increased density and the detonation speed. Getting the high explosive lenses right is a real bastard though. The literatures pretty light on the explosive details strangely enough.
So, basically, your common or garden "building it in his cave" terrorist stereotype is going to have to go for the gun type. All the cross section and neutron transport data's available, you only need some world war II tech high explosives and machining ability and you're done. Thing is you're limited to highly enriched uranium.
Ok, so nobody's serious suggesting that any non-governmental group is enriching their own uranium (at least I hope not). So they have to aquire very high U235 content uranium from somewhere. Where's the only place you find this? Bombs. Basically I reckon that anyone in a position to sell terrorists material for a bomb is in a position to sell them one pre-assembled.
Around 5% of shipping containers imported into the UK go through a full customs inspection. I think it's similar in the US. Why would they bother launching one when they could drive it to their target with ease?
The destruction caused would only really be the same as the equivalant convential bomb without the radioactive content. The only real consequences are a result of a combination of peoples general ignorance of all things nuclear and the fact that it's a useful tool for governments to keep us good and scared. In other words: panic and a reluctance to return to the blast area. The only exception is if the forces of "them" manage to aquire some real nasty stuff- particulate strontium 90 or some cesium 137. These would work (kinda) as a real area denial weapon but still wouldn't cause mass casualties.
A 'proper' fission bomb on the other hand is a different matter. Even a small one would wipe out a good portion of a major city and kill tens of thousands of people plus.
That's one of the reasons why the BBC rocks. Personally I think it's worth the price of the licence fee for just the BBC news.
Actually, I don't think actually handling it outside the body is that much of a big deal. It's only regarded as such nasty stuff because if you ingest some it winds up in your bone marrow.
It tastes like...burning!
Ok, world blows up, bits flying, "don't panic", "coming soon yadda yadda". Ends. I see people talking about what the cast look like and stuff- am I missing the correct trailer?
I still make my own fireworks though. You can't buy good, factory produced ones here (UK). Does that make me immature?
They only reference one study, published in "Home Power" magazine, written by two people who appear to work for solar panel manufacturers (I think its this one: http://www.ecotopia.com/apollo2/knapp/PVEPBTPaper. pdf)
Anyone got a better source? I admit my info's a bit out of date- I had a lecture a couple of years ago from one of materials science prof's and that's about it. Can't seem to find anything definative on google - seems to be a lot of debate about how you make the calculations. Chiefly that many pro solar studies ignore the fact that you need a bunch of big, deep cycle batteries (with a life time of only a couple of years) to make a practical solar system. Many of the anti-solar people tend to use older silicon refining energy figures though.
Same go's for playing with old microwave ovens. Just for the record, by the way, even if he screws up royally he's not going to get cancer from his microwave- non-ionising radiation you see. He could cook himself though- that'd probably suck.
I think this kind of nanny "but you might hurt yourself" attitude is going to harm future science education. Already it's at the point where you can no longer do a bunch of demonstration experiments in the classroom. Big sparking things, stuff exploding- that's what provided the hook to get me into physics.
Anyone have a figure for how efficient the "mirror type" method of solar is?
Don't forget the really big problem with solar: energy returned for energy invested. A big block of purified semi conductor takes a lot of energy to make. It means you have to run your solar cells for a very, very long time before your net energy gain is positive.
I always thought that explosion was a cover for a underground nuclear test. You see, the only way to be really, really sure your nuke design works as expected is to set one off. You can't do this above ground, openly because people would get upset (i.e. the US, possibly even china). It is possible to set off a nuke underground in a chamber packed with charcoal to absorb a lot of the energy and still get meaningful data. BUT this still produces a fairly characteristic seismic signature. You could cover this up with a BIG conventional explosion at the same time in approximately the same area.,p> How's that for a nice conspiracy theory?
Asshat who happens to have a blog gets job at google. For two weeks. Then they fire him.
I mean, really, if everyone who got fired for being bad at their job and talking crap online made the front page of /. there wouldn't even be enough space for the important stories about "battery life extenders". (BatMax: the worst slashdot 'news' ever?)
why is 4294967297 not prime? by Hüseyin KARAGÜLLE
(0.04 seconds)
It would appear that human intuition has gone the way of a good memory for facts: useless in the age of google.(I am fully aware that this is not representative of a normal intuitive descision. There is no need to point it out)
Don't knock the geology majors either. After all, someone has to find us all that oil. Too boring a job for us physicists and engineers- leave it to the rock monkeys.
That's because intergalactic baryons not only fill a gap in scientists' understanding of the universe, but they may also lead to a better understanding of "dark matter," a mysterious and unseen form of matter that has so far only been detected by the gravitational pull it exerts on other bodies in the universe. "If we are right, each single one of these filaments is connected to a cloud of dark matter," said Nicastro. "If there wasn't dark matter there, or something with strong gravity that pulled on the matter in these filaments, we wouldn't have galaxies or filaments." Rather, the baryons would be pulled into galaxies and the galaxies into each other.
Basically speaking it could be that the reason this big cloud of baryons hasn't collapsed into stars is because of dark matter.
When I got to uni I tried the same thing. Installed a different version on a lab PC next to a printer that I had occasionally seen an admin login to. Came back the next day, my program was gone and my user account was frozen with a "Please contact system administrator" message. Turned out that the sys admin in the physics department was a hardcore old unix bod who'd been an admin since the days you programmed with punch cards. He had seen it all. The computers allowed a boot from floppy but logged it and alerted him in real time. He watched me install my program on the CCTV, then watched me log into another computer so he had my username. Dude was in a different league from my school admin!
Luckily Physics had it's own rules for what happened if you got caught "hacking". First time you only got a slap on the wrist and had the rules carefully explained, 2nd time was where the restricted computer use came in.