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"Todd Rich" wrote in message
... DU is a very mild alpha emitter. Alpha particles are stopped by a sheet of paper or your skin. Nasty inside though. It's also a heavy metal like mercury and lead. Tim -- "California is the breakfast state: fruits, nuts and flakes." Website: http://webpages.charter.net/dawill/tmoranwms |
On Thu, 21 Apr 2005 00:04:24 -0500, "Tim Williams"
wrote: Actually, it is! As I recall, removed granite waste is a low-level radiation "hazard". I don't believe that for a moment. Granite has sod-all radioactivity. Get a lump, try counting it - not easy, even with good tools. The risk from granite is because it's found in large underground masses and the daughter product is a gas. This can travel, so if you have a house with a suitable basement and no ventilation then you can be concentrating the radon from a huge quantity of rock. If you live in a stone-built house on pillars though, no hazard at all. |
On Thu, 21 Apr 2005 12:38:04 -0500, Rex B wrote:
So where does one buy a geiger counter, if one were so inclined? You start out by thinking what on earth you want it for. Then you buy the right sort. You also need to read up on radiation, its monitoring, its hazards and its devices. This is _not_ a simple subject (although reading military training pamphlets is often a good simple start - the relevant FM is probably on-line) If you buy a mil-surplus G-M then you have three problems; it's insensitive, because it was designed for measuring fairly high rates. Secondly it's _really_ insensitive, because it's 30 years old and the tube has gone soft - GM tubes age badly, especially those sensitive to beta. Thirdly it's likely to run on valves and require some weird 90V battery that's no longer available. So if you want to play science, buy a brand new (or still-boxed surplus) tube and build yourself a transistor power supply and counter circuit for it. Here in the UK, the military didn't use that many G-M devices. The standard battlefield meter was an ionisation chamber device, because this is more appropriate for military levels. For training there was a very similar meter, except it was a different case colour (black and silver). This did use a G-M tube and was sensitive enough to sniff out small training sources, pinned to a squaddie's battledress. For civil defence use, the standard device was a G-M tube mounted above one of the ROC's bunkers. http://www.scottishroc.org.uk/theroc/monitoring.html There were also hand-held variants (cream metal cases) In later years these were all replaced by variants of the ubiquitous Plessey PDRM82 http://www.users.globalnet.co.uk/~mccamley/pdrm82a.htm http://www.users.globalnet.co.uk/~mccamley/pdrm82.htm These are still around on eBay ($50 street price) and the surplus market (Bull electrical) as good NOS. They're robust, they use common batteries, they;re just the ticket for environmental monitoring and best of all they're PDRM82's. It's a problem with low-level env radiation monitoring that calibration is a Black art and the only way to get decent results is for everyone to be using the same meter. http://hps.org/publicinformation/ate/q4099.html -- Cats have nine lives, which is why they rarely post to Usenet. |
"bw" wrote in message ... "Al Dykes" wrote in message ... In article , Tim Wescott wrote: John Sefton wrote: "Ignoramus20427" wrote in message ... On Wed, 20 Apr 2005 01:27:17 GMT, Bruce W.1 wrote: I've read that depleted uranium is six times as dense as lead. It would be nifty to have a chunk of it, that is if it's not radioactive. only 1.5 times heavier. 30 years ago the Toronto Science Museum had a brick-sized chunk of DU on display under a plexiglass dome. The dome had a hole for your hand and you could lift the brick. impressive heft. A standard brick has a volume of about 1 liter, so your DU brick weighed 19 kilograms. Interesting. DU must have about the same specific gravity as gold. (Slightly higher, I'd guess) |
"John Sefton" wrote in message news:d49i7m$on9 Interesting. DU must have about the same specific gravity as gold. (Slightly higher, I'd guess) Gold = 19.32 Depleted Uranium = 18.7 |
"Lane" lane (no spam) at copperaccents dot com wrote in message ... "John Sefton" wrote in message news:d49i7m$on9 Interesting. DU must have about the same specific gravity as gold. (Slightly higher, I'd guess) Gold = 19.32 Depleted Uranium = 18.7 Well... slightly lower, then! :^) That "d" word obviously makes all the difference... |
On Fri, 22 Apr 2005 01:03:47 +0100, Andy Dingley wrote:
On Thu, 21 Apr 2005 00:04:24 -0500, "Tim Williams" wrote: Actually, it is! As I recall, removed granite waste is a low-level radiation "hazard". I don't believe that for a moment. Granite has sod-all radioactivity. Get a lump, try counting it - not easy, even with good tools. Hm. That's interesting, because I played with the Geiger counter last night (technically a "Scintillation Meter"), and found the following: Radiation survey of everyday objects: Background radiation, 4 sites inside house: 1.5 Counts per Second (CPS) Background radiation, 4 sites outside house: 1.5 CPS 4 over-ripe bananas, sensor in contact with skin: 3 CPS Clean diapers: 1.5 CPS (no detectable radiation; same as background) Dirty diapers, measured at top of diaper pail: 2 CPS 6 month old kid: 1.5 CPS plus drool and two giggles "First Alert" smoke detector, with Americium goodness: 50 CPS on surface 10 year old Trijicon (Tritium) gunsights on Glock 19: 1.5 CPS Granite boulder, roughly 1 meter in diameter. Pink: 4 CPS Black: 3 CPS Blue/black boulder of unknown ignious type: 1.5 CPS Garden soil: 1.5 CPS Obviously this is only a slightly scientific survey, but shows some interesting non-background results. The risk from granite is because it's found in large underground masses and the daughter product is a gas. This can travel, so if you have a house with a suitable basement and no ventilation then you can be concentrating the radon from a huge quantity of rock. If you live in a stone-built house on pillars though, no hazard at all. Right. Measurable doesn't mean dangerous. Well, except in the case of the diaper pail above (trust me on this one). For the record, the kid just started on bananas. I should check his other foods, just out of curiousity. Dave Hinz |
Dave, thanks for quatifying the radioactivity with your experimentation.
You have proved that granite and banananas are indeed radioactive. The level is indeed low but it is there for those that are hypersensitive to the idea of radioactivity. For fun with hypersensitivty to radiation, carve yourself a key fob out of granite and when you meet one of those idiots, show it to him and then tell him that it is radioactive. Then watch him freak. -- Why isn't there an Ozone Hole at the NORTH Pole? |
Thanks for the report Dave! :) -Alvin
Hm. That's interesting, because I played with the Geiger counter last night (technically a "Scintillation Meter"), and found the following: Radiation survey of everyday objects: Background radiation, 4 sites inside house: 1.5 Counts per Second Background radiation, 4 sites outside house: 1.5 CPS 4 over-ripe bananas, sensor in contact with skin: 3 CPS Clean diapers: 1.5 CPS (no detectable radiation; same as background) Dirty diapers, measured at top of diaper pail: 2 CPS 6 month old kid: 1.5 CPS plus drool and two giggles "First Alert" smoke detector, with Americium goodness: 50 CPS 10 year old Trijicon (Tritium) gunsights on Glock 19: 1.5 CPS Granite boulder, roughly 1 meter in diameter. Pink: 4 CPS Black: 3 CPS Blue/black boulder of unknown ignious type: 1.5 CPS Garden soil: 1.5 CPS Obviously this is only a slightly scientific survey, but shows some interesting non-background results. Measurable doesn't mean dangerous. Well, except in the case of the diaper pail above (trust me on this one). For the record, the kid just started on bananas. I should check his other foods, just out of curiousity. Dave Hinz |
On Fri, 22 Apr 2005 11:03:59 -0700, Bob May wrote:
Dave, thanks for quatifying the radioactivity with your experimentation. You have proved that granite and banananas are indeed radioactive. The level is indeed low but it is there for those that are hypersensitive to the idea of radioactivity. For those who over-react to non-issues, I hope you mean? For fun with hypersensitivty to radiation, carve yourself a key fob out of granite and when you meet one of those idiots, show it to him and then tell him that it is radioactive. Then watch him freak. Heh. I think the fact that baby poop is measurably radioactive is fun enough. |
william_b_noble wrote:
there was a mod to the L-1011 airplane that involved putting depleted uranium weights as counterbalances on a couple of control arms - I wonder what happens to those weights when the planes are decomissioned. and, if you go to iraq, near the kuwait border, you will find a fair amount of it from the desert storm campaign - of course it's a bit of a trip. Some of the aircraft I have worked on over the years have had DU in them as mass balance weights for flight controls. It is relatively benign. We were under strict guidance to not drill, grind, or otherwise alter the weights. There were procedures in place that dealt with crash salvage and recovering the weights for disposal, if it was required. I am under the impression that the OP is suffering from a bad case of ignorant, and perhaps should do his own homework to see if he really wants to deal with the stuff. If he wants heavy, lead is probably his best bet for safe and easy. Maybe solid tungsten, if he has the budget. I expect that if the OP were in a position to actually require DU, he would already know the risks vs. the benefits, as well as the sources. Cheers Trevor Jones |
"Bob May" wrote in message
... For fun with hypersensitivty to radiation, carve yourself a key fob out of granite and when you meet one of those idiots, show it to him and then tell him that it is radioactive. Then watch him freak. Hmmmm, if these dupes carry around counters, you could have some good fun.. like drill out a few smoke alarms and encase the bits in a plastic fob like you said. Radiation ought to be negligible enough (with the alphas contained in the plastic and protected by skin and pocket lining), yet still detectable. Or if you've broken a bright orange ceramic dish, it might be a uranium colored glaze - those set off a counter too. Tim -- "California is the breakfast state: fruits, nuts and flakes." Website: http://webpages.charter.net/dawill/tmoranwms |
On Sun, 24 Apr 2005 00:03:38 -0500, "Tim Williams"
wrote: "Bob May" wrote in message ... For fun with hypersensitivty to radiation, carve yourself a key fob out of granite and when you meet one of those idiots, show it to him and then tell him that it is radioactive. Then watch him freak. Hmmmm, if these dupes carry around counters, you could have some good fun.. like drill out a few smoke alarms and encase the bits in a plastic fob like you said. Radiation ought to be negligible enough (with the alphas contained in the plastic and protected by skin and pocket lining), yet still detectable. Or if you've broken a bright orange ceramic dish, it might be a uranium colored glaze - those set off a counter too. Tim Hmmm... orange. I've always suspected that's what the nacho cheese sauce was at little league parks, nuclear waste. Pete Keillor |
In rec.crafts.metalworking Tim Williams wrote:
"Bob May" wrote in message ... For fun with hypersensitivty to radiation, carve yourself a key fob out of granite and when you meet one of those idiots, show it to him and then tell him that it is radioactive. Then watch him freak. Hmmmm, if these dupes carry around counters, you could have some good fun.. like drill out a few smoke alarms and encase the bits in a plastic fob like you said. Radiation ought to be negligible enough (with the alphas contained in the plastic and protected by skin and pocket lining), yet still detectable. Or if you've broken a bright orange ceramic dish, it might be a uranium colored glaze - those set off a counter too. Tim -- "California is the breakfast state: fruits, nuts and flakes." Website: http://webpages.charter.net/dawill/tmoranwms Naw...go for the cheap and easy route. Coleman lantern mantles. |
For those who over-react to non-issues, I hope you mean?
That's probably a better way to put it. -- Why isn't there an Ozone Hole at the NORTH Pole? |
In sci.engr.metallurgy Todd Rich wrote:
Naw...go for the cheap and easy route. Coleman lantern mantles. [Todd Rich] I guess that's Be10? Half life = 2.7x10^6 years, beta-0.56; no gamma Abundance is listed as zero in my book tho. :/ The problem with those was ordinary Be in the lungs. Do they have another metal I'm missing? Alvin in AZ (panix here too;) |
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"Ned Simmons" wrote in message
... I guess that's Be10? Half life = 2.7x10^6 years, beta-0.56; no gamma Abundance is listed as zero in my book tho. :/ The problem with those was ordinary Be in the lungs. Do they have another metal I'm missing? Cerium Nah, actually thorium has the highest melting point of any oxide. I forget what it is offhand, something like 3000 or 3200°C? Ceria may've replaced it nowadays...that wouldn't be suprising. I'd think something like zirconia or magnesia would be cheaper while still retaining the high melting point, though. Must be the emission spectrum of the rare earths that they need. Tim -- "California is the breakfast state: fruits, nuts and flakes." Website: http://webpages.charter.net/dawill/tmoranwms |
Check this out:
Tale of the Radioactive Boy Scout http://www.dangerouslaboratories.org/radscout.html On Sun, 24 Apr 2005 23:45:18 -0500, "Tim Williams" wrote: "Ned Simmons" wrote in message ... I guess that's Be10? Half life = 2.7x10^6 years, beta-0.56; no gamma Abundance is listed as zero in my book tho. :/ The problem with those was ordinary Be in the lungs. Do they have another metal I'm missing? Cerium Nah, actually thorium has the highest melting point of any oxide. I forget what it is offhand, something like 3000 or 3200°C? Ceria may've replaced it nowadays...that wouldn't be suprising. I'd think something like zirconia or magnesia would be cheaper while still retaining the high melting point, though. Must be the emission spectrum of the rare earths that they need. Tim |
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In rec.crafts.metalworking Ned Simmons wrote:
(snip) Apparently a mixture of thorium and cerium oxides. Ned Simmons Shows how much my memory has degraded since high school. At least it was one that sounded similar. Todd |
Cerium
None of the naturally occurring Ce's are shown to have radiation. Ce136 0.19% Ce138 0.26% Ce140 88.47% Ce142 11.08% Th232 100% shows a half-life of 1.39x10^10 years, alpha and gamma Nah, actually thorium has the highest melting point of any oxide. I forget what it is offhand, something like 3000 or 3200?C? ThO2 3050-C ;) CeO2 2600-C ZrO2 2700-C MgO 2800-C BeO 2585-C --this one I heard about back in the 70's The caution was not to "first light" them any where but outside. Ceria may've replaced it nowadays...that wouldn't be suprising. I'd think something like zirconia or magnesia would be cheaper while still retaining the high melting point, though. Must be the emission spectrum of the rare earths that they need. Tim Alvin in AZ (libertarian and librarian;) |
Depleted uranium is radioactive and anyone uncovering a shell made from it
gets radioactive poisoning, bad stuff... "Tim Shoppa" wrote in message ups.com... I've read that depleted uranium is six times as dense as lead. Not true, although it is denser. If not then does anyone know where I can get a small piece? Get in a war with the US or NATO and the military will deliver it, no charge even! Tim. |
"Digby Millikan" wrote in message ... Depleted uranium is radioactive and anyone uncovering a shell made from it gets radioactive poisoning, bad stuff... False nonsense. Vaughn |
In rec.crafts.metalworking Digby Millikan wrote:
Depleted uranium is radioactive and anyone uncovering a shell made from it gets radioactive poisoning, bad stuff... Depleted uranium is a mild alpha emitter. Your skin will stop the alpha particles. Breathing in particles of DU is a different matter, but just picking one up is not likely to cause a problem. |
Depleted uranium is used as counterweights in the control system of many
aircraft. It is usually re-cycled when aircraft are junked. I also saw a pair of DU penatraters from some tank rounds at an Army Surplus store, but they wanted a young fortune for them. Far more than the metal content was worth. What in the world do you want to do with it any way? Its difficult to machine, very hard, also its pyrophoric. Meaning the hot metal shavings have a tendence to burn when exposed to the O2 in the air. Breathing the fumes from this can be deadly, as others have mentioned DU gives off alpha radiation, which is relatively safe, until it gets inside your lungs. |
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