Not likely. Am241 is an alpha emitter. Alphas have essentially zero penetrating power, so they never leave the detector. It also emits a puny gamma ray at 60 keV. I doubt that would be detectable at an appreciable distance.
Fine. Show them how radioactive bananas, Brazil nuts, and KCl salt substitute are, then, all of which are _ingested_. They all contain fairly high amounts of K-40, and Brazil nuts also contain Ra226! This page has a nice rundown of naturally-occurring radioactive sources present in our environment, including places that have extremely high naturally-occurring background radiation levels.
For those that are curious, Y-90 has a half life of 64 hours and decays into (stable) Zr-90 via the emission of a 2.28 MeV beta- particle. It has a fairly high specific activity of 2.5x10^5 Ci/g (naturally, given its short half life). It is mainly produced from Sr-90, which is fairly dangerous if ingested because the body treats it like calcium - it ends up locked in your bones where it irradiates surround tissue - like bone marrow that produces blood cells. Here is a datasheet from a supplier - you can get it in activities of 1 Curie! That's 37 GBq.
...since the last N-plant went active in the US...
It's alright - you can say the 'N' word! Even some environmentalists are saying it (gasp!!) Go ahead, it's easy. Nooo-cleee-urrr. Nu-cle-ur. Nuclear. There, that wasn't so hard. I think we've made great progress.
Obligatory content: I'm convinced that the only way out of our energy 'crisis' is to adopt IFR technology. This interview in particular spotlights its technical merits and the political stumbling blocks that have been thrown in its path.
Mod was a very popular expression in the 60's for everything that was hip, cool, groovy, in, far out, etc. Kinda like the "Austin Powers: The spy who shagged me" movie, but in real life. I think the original poster meant 'mid-90s', but wrote 'mod-90s'.
I agree that specific solution works, but what about the general cases of the other 3 length permutations of 'r' and 'b'. As my table shows, all the nodes have unique, universal directions to them except nodes 1, 4, 7, and 8. These nodes have monocolor loops point to them. Try 'bbb' and 'rrr' from any node, and you'll find 3 terminal nodes for each path.
True, if as you say the carbon is atmosphere-o-genic. I fear that the easiest (and cheapest) route may be to crack aliphatic hydrocarbons from fossil fuels into both the buckyballs and H2, so we're no better off than burning it outright.
Given this graph, what about the 'traps' that exist for directions 'rrr' and 'bbb'? If you number the nodes top to bottom, left to right as 1-8, nodes 1, 2, and 4 all are destinations for 'rrr' depending on your starting point. Similarly, nodes 6, 7, and 8 are all destinations for 'bbb' depending on where you start. Does the problem definition say you must follow the whole direction, i.e. you must always traverse 3 arcs, or is it 'legal' to stop when you've reached your destination (assuming you know where that is). If the latter is true, then the correct destination for 'rrr' is node 2, and node 6 for 'bbb'.
Thanks for the reply. I guess the bottom line is how small the buckyball fragments are. My fear is that upon rupture, some of the released hydrogen will combine with the newly-ruptured bucky fragments, creating those evil hydrocarbons. Unless we find some extremely clever scientists, I doubt we'll see buckyballs with a little trap door on them to let the hydrogen out. barring that, there will be various sizes of carbon structures floating around (I liken it to nuclear fission where there's a two-humped distribution of fission fragments - perhaps I'm way off base).
...but each burst buckyball is 60 carbon atoms floating around in your fuel. Aren't you right back to "hydrocarbons" if you burn this fuel, and won't the carbon poison fuel cell membranes? It's a cool trick _iff_ you can strip the carbon out efficiently before the hydrogen is used.
Leaving the issue of critical magnetic fields aside, my proposal would be to standardize _all_ loads to 50VDC. It doesn't matter if the current is very high anymore with superconductors (again, aside from Bcrit issues). If you need higher voltage for specific purposes (plasma generators, etc) DC-DC converters are available at 95%+ efficiency.
I realize that you can't eliminate the insulation all together, but a few mils of teflon will handle 600+ volts vs 20 meters of air or 3 meters of porcelain they use now for 500kV.
If we go with my original proposal, that being reduce the voltage 50 volts, you can just about safely touch that voltage barehanded regardless of the current passing thru the conductor and not receive a dangerous shock.
Apparently it's not very dangerous at all. SF6 is also known as 'anti-helium' - it's the gas they use to create the "Barry White Effect".
Just like helium is less dense than air and makes your voice appear much higher than normal, SF6 is much more dense than air and lowers your voice accordingly.
I'm no chemist, but these MSDS don't seem too concerned with exposure to SiO4, Si2O6, or Si3O8. Only silane has an exposure limit established (5 ppm). It's not like pentaborane - an 'accident' involving the illegal disposal of a cylinder of it nearly(*) killed a friend of mine back in the 80's. The exposure limits for pentaborane are more like 0.005 ppm.
(*) Nearly, meaning it actually did 'kill' him several times on the way to the hospital by inducing multiple heart attacks.
Look at it from another perspective - wouldn't it be far cheaper to run very high current on a small superconducting cable than extremely high voltage on a small non-superconducting cable? The superconducting cable would:
have much less insulation
have much shorter/no insulators/standoffs when run overhead
No need for installing it high up for safety reasons
No need for huge swaths of cleared right-of-way
be able to be buried along with other utility cables/pipes, without super-expensive high tech gas-filled cables.
be able to be repaired without gloves and a huge investment in safety equipment
I'd say the benefits outweigh the costs by a large margin.
Also, with superconductors, there's no need to use AC at all - the national grid could be standardized on some magic voltage between 5 and 50 VDC, say, and since we're talking superconductors, household service would be 5-50V @ 1-10kA. No transformer losses (no transformers), no skin effect losses, underground service everywhere (no more utility poles!!!), no RFI from corona discharge. I'd say it's a serious win for the SC.
Patently false. Even as Amateur Radio charges into the digital radio future, it will almost certainly still have analog transmission modes. We are allowed (and encouraged) to make our own equipment and to provide emergency communications and advance the radio art, which are part of our justification for existence. Since digital modes will take a long time to become de rigueur around the world, AM, FM, and SSB will be around for a long time.
There are still tons of operators that run full double sideband, full carrier AM - although their signals are not the most spectrum-efficient on the air, their audio is usually great-sounding.
Ah! I understand now. I wonder what it could be best used for? It suffers from (or is enhanced by!) sporadic-E propagation, and is also somewhat affected by the sunspot number. I know 10m and 6m are dead as doornails right now at the bottom of the cycle. Maybe it would be a decent place for pure (as opposed to the current backwards-compatible) digital terrestrial radio.
I know of a few amateur radio guys that wouldn't mind having it for a big ATM-style data channel. (Me, me!!!)
I expect that 30 MHz will eventually be repurposed.
Why did you mention 30MHz? Channel 2 in the US starts at 54 MHz, right? 30MHz is just above the amateur radio 10m band (ends at 29.7 MHz). Between 30MHz and 50MHz is a no-mans-land of 'stuff' including ancient cordless phones and baby monitors, fixed, mobile, land mobile, an ISM band, and even a little radio astronomy. 50MHz is the beginning of the amateur radio 6m band that extends right up against channel 2 at 54 MHz. If channel 2 goes away, I'll be tickled - no more RFI to channel 2 from 6m operations.
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Not likely. Am241 is an alpha emitter. Alphas have essentially zero penetrating power, so they never leave the detector. It also emits a puny gamma ray at 60 keV. I doubt that would be detectable at an appreciable distance.
Fine. Show them how radioactive bananas, Brazil nuts, and KCl salt substitute are, then, all of which are _ingested_. They all contain fairly high amounts of K-40, and Brazil nuts also contain Ra226! This page has a nice rundown of naturally-occurring radioactive sources present in our environment, including places that have extremely high naturally-occurring background radiation levels.
For those that are curious, Y-90 has a half life of 64 hours and decays into (stable) Zr-90 via the emission of a 2.28 MeV beta- particle. It has a fairly high specific activity of 2.5x10^5 Ci/g (naturally, given its short half life). It is mainly produced from Sr-90, which is fairly dangerous if ingested because the body treats it like calcium - it ends up locked in your bones where it irradiates surround tissue - like bone marrow that produces blood cells. Here is a datasheet from a supplier - you can get it in activities of 1 Curie! That's 37 GBq.
It's alright - you can say the 'N' word! Even some environmentalists are saying it (gasp!!) Go ahead, it's easy. Nooo-cleee-urrr. Nu-cle-ur. Nuclear. There, that wasn't so hard. I think we've made great progress.
Obligatory content: I'm convinced that the only way out of our energy 'crisis' is to adopt IFR technology. This interview in particular spotlights its technical merits and the political stumbling blocks that have been thrown in its path.
Mod was a very popular expression in the 60's for everything that was hip, cool, groovy, in, far out, etc. Kinda like the "Austin Powers: The spy who shagged me" movie, but in real life. I think the original poster meant 'mid-90s', but wrote 'mod-90s'.
Horribly cool! Thanks for the information.
The 60's were mod, just so you know.
Cash-In-Gin only works if you're a Beefeater, your last name is Gordon, or are from Bombay.
Oh, you meant "Cashing-In!". Nevermind...
I can dream, can't I? 8-) That's only 2984A. Child's play! 8-)
I agree that specific solution works, but what about the general cases of the other 3 length permutations of 'r' and 'b'. As my table shows, all the nodes have unique, universal directions to them except nodes 1, 4, 7, and 8. These nodes have monocolor loops point to them. Try 'bbb' and 'rrr' from any node, and you'll find 3 terminal nodes for each path.
True, if as you say the carbon is atmosphere-o-genic. I fear that the easiest (and cheapest) route may be to crack aliphatic hydrocarbons from fossil fuels into both the buckyballs and H2, so we're no better off than burning it outright.
Thanks for the reply. I guess the bottom line is how small the buckyball fragments are. My fear is that upon rupture, some of the released hydrogen will combine with the newly-ruptured bucky fragments, creating those evil hydrocarbons. Unless we find some extremely clever scientists, I doubt we'll see buckyballs with a little trap door on them to let the hydrogen out. barring that, there will be various sizes of carbon structures floating around (I liken it to nuclear fission where there's a two-humped distribution of fission fragments - perhaps I'm way off base).
Slightly OT, but has anyone actually observed a decaying proton? Wikipedia says no.
...but each burst buckyball is 60 carbon atoms floating around in your fuel. Aren't you right back to "hydrocarbons" if you burn this fuel, and won't the carbon poison fuel cell membranes? It's a cool trick _iff_ you can strip the carbon out efficiently before the hydrogen is used.
Leaving the issue of critical magnetic fields aside, my proposal would be to standardize _all_ loads to 50VDC. It doesn't matter if the current is very high anymore with superconductors (again, aside from Bcrit issues). If you need higher voltage for specific purposes (plasma generators, etc) DC-DC converters are available at 95%+ efficiency.
If we go with my original proposal, that being reduce the voltage 50 volts, you can just about safely touch that voltage barehanded regardless of the current passing thru the conductor and not receive a dangerous shock.
Just like helium is less dense than air and makes your voice appear much higher than normal, SF6 is much more dense than air and lowers your voice accordingly.
(*) Nearly, meaning it actually did 'kill' him several times on the way to the hospital by inducing multiple heart attacks.
- have much less insulation
- have much shorter/no insulators/standoffs when run overhead
- No need for installing it high up for safety reasons
- No need for huge swaths of cleared right-of-way
- be able to be buried along with other utility cables/pipes, without super-expensive high tech gas-filled cables.
- be able to be repaired without gloves and a huge investment in safety equipment
I'd say the benefits outweigh the costs by a large margin.Also, with superconductors, there's no need to use AC at all - the national grid could be standardized on some magic voltage between 5 and 50 VDC, say, and since we're talking superconductors, household service would be 5-50V @ 1-10kA. No transformer losses (no transformers), no skin effect losses, underground service everywhere (no more utility poles!!!), no RFI from corona discharge. I'd say it's a serious win for the SC.
There are still tons of operators that run full double sideband, full carrier AM - although their signals are not the most spectrum-efficient on the air, their audio is usually great-sounding.
That kinda puts a new spin on the phase "EFF you!"
Who knew?
I know of a few amateur radio guys that wouldn't mind having it for a big ATM-style data channel. (Me, me!!!)
Why did you mention 30MHz? Channel 2 in the US starts at 54 MHz, right? 30MHz is just above the amateur radio 10m band (ends at 29.7 MHz). Between 30MHz and 50MHz is a no-mans-land of 'stuff' including ancient cordless phones and baby monitors, fixed, mobile, land mobile, an ISM band, and even a little radio astronomy. 50MHz is the beginning of the amateur radio 6m band that extends right up against channel 2 at 54 MHz. If channel 2 goes away, I'll be tickled - no more RFI to channel 2 from 6m operations.