DANGER ! RADIOACTIVE WRIST WATCHES!!
Andre de Guerin
Good thing I bought that geiger counter .. :)
LEE
mand...@gtonline.net (Andre de Guerin) wrote:
> http://news.bbc.co.uk/hi/english/health/newsid_1080000/1080264.stm
>
> Good thing I bought that geiger counter .. :)
>
Cobalt 60 contaminated wristbands...YUK!!! Alphas,betas,gammas, high
speed electrons...Beta burns can disturb one!! Alphas can be stopped
with a piece of paper. Don`t eat any R active particles as they
gravitate to certain parts of the body and cause ionizing damage.
Always have your calibrated survey meter/geiger counter at the ready.
LEE
Sent via Deja.com
http://www.deja.com/
Philip Pemberton
news:3a439009...@news.virgin.net...
> http://news.bbc.co.uk/hi/english/health/newsid_1080000/1080264.stm
>
> Good thing I bought that geiger counter .. :)
Pity the rubber strap irritates my wrist :-(
Anyone seen those old glow-in-the-dark clocks (the REALLY old ones) that
used radon/radium (?) paint? Nasty... The closest thing to radioactivity in
my watch is AFAIK either the lithium battery or the electroluminescent (EL)
backlight panel.
--
Phil.
http://www.philpem.f9.co.uk/
phi...@bigfoot.com
ae2...@wayne.edu
around 1980. I think they only manufactured them for one year (for
obvious reasons). Had a pellet of depleted uranium in it for
backlighting. I wonder how they designed the electronics to survive in
such an environment?
Martin Brown
ae2...@wayne.edu wrote:
> I used to have a radioactive writswatch! It was a Timex Nite-lite, made
> around 1980. I think they only manufactured them for one year (for
> obvious reasons). Had a pellet of depleted uranium in it for
> backlighting. I wonder how they designed the electronics to survive in
> such an environment?
Seems unlikely - most used tritium and a fluorescer in that era. It was
quite easy to convert a normal digital watch by adding tritiated fishing
floats behind the display. One minor side effect was that the whole
electronics could then be reset by exposure to strong sunlight or a
flashgun....
By comparison the WWII radium paint luminous dial watches really were hot
and would trigger radiation detectors at a distance. (Sadly the paint also
killed a lot of the girls who used it)
Regards,
Martin Brown
bob
i doubt it..
or should i say..
i would hope not..
i think it would be much more likely to finmd that they used something like
trittium
wrote in message ...
bob
manufacturoring process???
i know CO 60 is used in thickness guages, but i thought that was primarily
used with metals, not plastic..
Andre de Guerin wrote in message <3a439009...@news.virgin.net>...
Andre de Guerin
>I used to have a radioactive writswatch! It was a Timex Nite-lite, made
>around 1980. I think they only manufactured them for one year (for
>obvious reasons). Had a pellet of depleted uranium in it for
>backlighting. I wonder how they designed the electronics to survive in
>such an environment?
Good question - I suspect with something as simple as a divide by 15
counter it wouldn't matter unless the radiation was REALLY high .
I know that chips designed for satellite use are "radiation hard" .
Andre de Guerin
BTW I checked EVERY SINGLE glowing dial watch in the house,
nothing .
My smoke alarm set it a'clicking though, through the metal case .
Andre de Guerin
Apart from a slightly foggy LCD it works fine .
Not sure about the calibration though ..
Nukie Poo
entered a scrap facility. It has happened several times before. I remember
the radioactive school chair legs incident as well as a Mexican kid who
found a Cs137 capsule in a junk yard and took it home and set it on the
mantle. It turned some of the crystal that was on display black and killed
everyone in the house one by one.
"bob" <nom...@nospam.com> wrote in message
news:dbQ06.1014$ti7.2...@paloalto-snr1.gtei.net...
dwight_...@my-deja.com
martin...@pandora.be wrote:
> >
> Seems unlikely - most used tritium and a fluorescer in that era. It
was
> quite easy to convert a normal digital watch by adding tritiated
fishing
> floats behind the display. One minor side effect was that the whole
> electronics could then be reset by exposure to strong sunlight or a
> flashgun....
>
Hi
I agree that it was most likely tritium but what does
a flashgun or sunlight have to do with reseting the electronics?
Dwight
Chris
dumb question, but where could I buy a geiger counter??? I'd just like to
have one to fool around with...
--
Chris
Remove .nospam to reply.
= = = =
His Excellency Majesty President
Field Marshal General Doctor
Tenured Professor Licensed
Electrician And Supreme Astronaut
= = = =
"LEE" <lee...@my-deja.com> wrote in message
news:920e5f$qlj$1...@nnrp1.deja.com...
tadchem
"Nukie Poo" <paul...@sprynet.com> wrote in message
news:920pkl$2o1$1...@slb2.atl.mindspring.net...
> From scrap steel contamination. An old Cobalt therapy machine could've
> entered a scrap facility. It has happened several times before. I
remember
> the radioactive school chair legs incident as well as a Mexican kid who
> found a Cs137 capsule in a junk yard and took it home and set it on the
> mantle. It turned some of the crystal that was on display black and
killed
> everyone in the house one by one.
I used to be a radiation safety officer and would get regular bulletins from
the Nuclear Regulatory Commission about such incidents.
There was an incident about 1990 in Brazil where a gleaner brought home a
pretty glowing piece of metal from a scrapyard and he and several others,
including at least one of his own children, died from the Cs-137 radiation.
The case of the radioactive school chair legs involved scrap iron from
Mexico that had been contaminated with Co-60, and another case of a steel
mill in Utah that had been contaminated by an accidentally discarded
radioactive source from an industrial licensee.
Since then, scrap mills and steel recycling plants in the US have been
required (Federal Regulations) to screen incoming materials for radioactive
sources. Not so with mills elsewhere. Radioactive materials are not so
carefully regulated outside the US. Fines and possible imprisonment are
applied for non-compliance. If you think the EPA is tough, try going afoul
of the NRC.
It is interesting to note that most incidents involving uncontrolled
radioactive exposure in the US occur in hospitals and clinics, as the result
of misadministration of therapeutic radiation (miscalculated doses, exposure
times, or misplaced sources).
Tom Davidson
Brighton, CO
John Sutter
A canister containing cobalt was stolen from a construction
site by employees of a scrap company. Unfortunately innocents
were also contaminated.
http://www.bkkpost.samart.co.th/news/BParchive/BP20000303/030300_News04.html
-j
William L. Bahn
Charles W. Shults III
it is barely more radioactive than the background. With a half-life in the
billions of years, you aren't going to make anything glow with it. You can
even buy the stuff from various vendors, such as Nuclear Metals. That's
where I get mine. It's great shielding for radioactive materials, even
better than lead.
Cheers!
Chip Shults
SPAM free Email - aic...@gdi.udu.net but remove the .baryon
PGP \\ 8B27 CFD5 AAD5 67EA BF00
Key // 7529 9CF6 C3D7 233C D4D9
Philip Pemberton
and look for something with the radiation warning symbol on it :-)
bob
depleted than it used to be...
if you haD a large enough mass you would be able to get it to glow...
a pretty blue color :)
no phosphor needed
Charles W. Shults III wrote in message ...
Andre de Guerin
<xtch...@yahoo.com.nospam> wrote:
>As a rule of thumb, I don't eat my watch... that being said, maybe this is a
>dumb question, but where could I buy a geiger counter??? I'd just like to
>have one to fool around with...
Try Bull Electrical . <www.bull-electical.com>
Andre de Guerin
<phi...@btinternet.com> wrote:
>"Andre de Guerin" <mand...@gtonline.net> wrote in message
>news:3a43ceb4...@news.virgin.net...
>> On Fri, 22 Dec 2000 21:08:25 -0000, "Philip Pemberton"
>> <phi...@btinternet.com> wrote:
>>
>> >"Andre de Guerin" <mand...@gtonline.net> wrote in message
>> >news:3a439009...@news.virgin.net...
>> >> http://news.bbc.co.uk/hi/english/health/newsid_1080000/1080264.stm
>> >>
>> >> Good thing I bought that geiger counter .. :)
>> >Yikes! Don't think my watch is contaminated tho' - it's a Zeon Tech
>ZR13999.
>> >Pity the rubber strap irritates my wrist :-(
>> >
>> >Anyone seen those old glow-in-the-dark clocks (the REALLY old ones) that
>> >used radon/radium (?) paint? Nasty... The closest thing to radioactivity
>in
>> >my watch is AFAIK either the lithium battery or the electroluminescent
>(EL)
>> >backlight panel.
>>
>> BTW I checked EVERY SINGLE glowing dial watch in the house,
>> nothing .
>> My smoke alarm set it a'clicking though, through the metal case .
>That'll be the Americium ionization-type smoke detector module. Open it up
>and look for something with the radiation warning symbol on it :-)
None of my other smoke alarms set it off though, just this one .
Must use plutonium or something (Am-241 is primarily an alpha emitter
IIRC which can't get through paper .)
Andre de Guerin
None ; it just meant that the chip was then able to be affected by the
flashgun . (the reflective layer on the display prevents light getting
to the chip normally) .
You can get the same effect if you take the back off a wristwatch then
flashgun it .
Andre de Guerin
<aic...@gdi.net> wrote:
> Depleted uranium is just that- depleted. The U-235 has been removed and
>it is barely more radioactive than the background. With a half-life in the
>billions of years, you aren't going to make anything glow with it. You can
>even buy the stuff from various vendors, such as Nuclear Metals. That's
>where I get mine. It's great shielding for radioactive materials, even
>better than lead.
Isn't it more toxic than lead though ?
Andre de Guerin
wrote:
>From scrap steel contamination. An old Cobalt therapy machine could've
>entered a scrap facility. It has happened several times before. I remember
>the radioactive school chair legs incident as well as a Mexican kid who
>found a Cs137 capsule in a junk yard and took it home and set it on the
>mantle. It turned some of the crystal that was on display black and killed
>everyone in the house one by one.
There was another incident where a machine's source got melted down
with some scrap steel to make rebars that were then used in people's
houses ! I
Andre de Guerin
http://www.chinatimes.com//english/esociety/89111605.htm
Charles W. Shults III
you have a mass large enough to melt. Even straight U-235 does not glow.
It's true that newer DU is sometimes less depleted than the older stuff, but
U-235 is still important enough to try to recover all that you can if you
are going to the trouble.
Look up AVLIS if you want to get some information about non-diffusion
isotope recovery methods. No more miles of tiny bore "chromatograph" style
tubing.
Charles W. Shults III
combusts readily in air. The dust (uranium oxide) is pretty toxic, but by
itself, the metal tends to be fairly inert. Not like some other metals I
can think of.
Charles W. Shults III
large size, and it had a sizable quantity of radium (half life of about 1260
years) in it. That used to be the material of choice, but americium is easy
to make and available. Am-241 is also subject to decay after a couple of
years and becomes useless for the purpose of ionizing the air.
All my Am-241 sources decayed in about 6 to 9 months to the point where
I had to replace them. You can get a standard set of Am-241 for alpha,
thallium-204 for beta, and cobalt-60 for gamma from many places. They're
pretty cheap.
Charles W. Shults III
Light itself should have no effect on it, with or without the reflector.
Therefore, it must be something other than light.
Consider that a flash tube uses high voltages and a fast switching time.
You are probably generating a tiny EMP that causes the effect when the tube
is very close. Try the following experiment.
Cover the watch with an opaque shield (but not metal foil) and trigger
the flash tube. It should still cause the same effect. Try a couple of
sheets of black construction paper and black plastic film.
bob
> You are probably thinking of Cesium-137. Uranium does not glow unless
>you have a mass large enough to melt. Even straight U-235 does not glow.
uranium doesnt glow???
i bet you it does...
all you need is enough of it and youll get crenkov (sp?) radiation...
especially if you have the U in a material other than air, ie water
I'm kinda gettin ya with a technicality here.... you need a critical ass for
that :)
>It's true that newer DU is sometimes less depleted than the older stuff,
but
>U-235 is still important enough to try to recover all that you can if you
>are going to the trouble.
true but the more dilute it becomes the harder it is to recover.
> Look up AVLIS if you want to get some information about non-diffusion
>isotope recovery methods. No more miles of tiny bore "chromatograph" style
>tubing.
actually there is some experimental work being done with an even better
laser based method of enrichment right now..
you blast a sample of your element with an ultra high intensity laser pulse
(>10^16 W /cm^2) and the intense magnetic field (on the order of >
Kilotesla) basically causes the same thing to happen in an electron
cyclotron resonance ion source.. you see heavier ions migrate to the outter
epriffery..
but due to the ridicuously high fields generated by the high peak power
source, the effect is proportionally more pronounced.... signifigant
enrichment can be had in only a few stages...
bob
it's also mildly radioactive, so i wouldnt wanna go ingesting, or inhaleing
it, but otherwise it's not all that bad..
plutonium is what you have to worry about
Andre de Guerin wrote in message <3a44b050...@news.virgin.net>...
bob
Andre de Guerin wrote in message <3a44aea4...@news.virgin.net>...
>On Fri, 22 Dec 2000 18:53:01 -0500, "Nukie Poo" <paul...@sprynet.com>
>wrote:
>
>>From scrap steel contamination. An old Cobalt therapy machine could've
>>entered a scrap facility. It has happened several times before. I
remember
>>the radioactive school chair legs incident as well as a Mexican kid who
>>found a Cs137 capsule in a junk yard and took it home and set it on the
>>mantle. It turned some of the crystal that was on display black and
killed
>>everyone in the house one by one.
>
>There was another incident where a machine's source got melted down
>with some scrap steel to make rebars that were then used in people's
>houses ! I
house..
Charles W. Shults III
air, you can't see the sort of Cerenkov glow that you can with cesium.
Uranium tends to have mostly neutron radiation which is very penetrating and
tends not to interact up close to the material. In order for uranium to
be useful for most reactions, you must slow the neutrons down with a
moderator. Otherwise, they are far from the local area before the do
interact, so any possible glow is far more diffuse.
Water is a pretty good moderator, but heavy water is better. Paraffin
wax is quite nice and I have used it successfully.
If you have enough uranium to be critical, you probably won't see the
glow if the geometry is right! Of course, people in the next town might.
But for critical masses of irregular geometry, it still is going to melt
before you see much Cerenkov radiation in air. And if it is that hot, it
will likely catch fire first. So uranium does not glow (except under very
special, restrictive situations).
As for kiloTesla mag fields, most material substances explode under the
forces required to create fields of 30 Teslas. Check out the National High
Magnetic Field Laboratory for examples. Present experiments to make high
Tesla fields may generate kiloTesla fields, but only for very short periods
of time- not long enough to enrich uranium. While there is a bit of secrecy
about the best and fastest methods of isotope enrichment (because weapons
programs never die!), there are some serious limits to what we can do today.
AVLIS and its spinoffs are still pretty good.
Even the lowly rail gun had problems in the beginning keeping the rails
from exploding- Lenz law in action.
bob
as seen in a pool reactor..
granted the uranium it's self may not be glowing, but it surely is what is
he ultimate source of the glow....
like i said... a technicality....
actually... wasnt there a few critticality accidents in the wee days of the
us nuke program where a few people were killed.. if I'm not mistaken one of
them claimed to see crenkov radiation from the uranium core...
> As for kiloTesla mag fields, most material substances explode under the
>forces required to create fields of 30 Teslas. Check out the National High
>Magnetic Field Laboratory for examples. Present experiments to make high
>Tesla fields may generate kiloTesla fields, but only for very short periods
>of time- not long enough to enrich uranium. While there is a bit of
secrecy
>about the best and fastest methods of isotope enrichment (because weapons
>programs never die!), there are some serious limits to what we can do
today.
I wasnt reffering to a CW feild naturally..
these sorts of fields are generated with high power short pulsed lasers..
were talking about interaction times of hundreds of femtoseconds here...
I have attached an article on this subject..
i cant find the one i was looking for..
this paper used a relativly low power laser, but they were still able to
generate fields ont he order of 60 T with 10^14 to 10 ^15 w/cm^2.....
thats about 6 orders of magnitude lower power densitys than what is capible
with larger laser systems...
LEE
I was lucky enough to find a newer "lab grade" counter at the local
flea market(probably stolen)3 yrs ago for $20..an absolute FIND!!!. It
operates using 2 D cells and each range is front panel calibrated using
some sort of predictable radioactive source. It has a stainless probe
that can be slid closed to then measure/detect gammas. I
use "background" radiation as a standard when measuring those orange
radioactive pottery pieces from the southwest. I`ve also measured the
older Coleman lantern silk bags that used to be radioactive b4 being
banned from the market. They read quite a few millirems close up and
probably emitted radon gas along with alphas and bettas. If you can`t
find a good used one (fles markets,etc),the cost of a good one from
Edmond Scientific may be a few hundred dollars depending on the level
of sofistication. Good luck, Lee
LEE
"Philip Pemberton" <phi...@btinternet.com> wrote:
> "Andre de Guerin" <mand...@gtonline.net> wrote in message
> news:3a439009...@news.virgin.net...
> >
> > Good thing I bought that geiger counter .. :)
ZR13999.
> Pity the rubber strap irritates my wrist :-(
>
> Anyone seen those old glow-in-the-dark clocks (the REALLY old ones)
that
> used radon/radium (?) paint? Nasty... The closest thing to
radioactivity in
> my watch is AFAIK either the lithium battery or the
electroluminescent (EL)
> backlight panel.
>
Does anyone remember the Tritium backlit watches that used to be on the
market? They banned these although the tritium emited too little
radiation to be measured. LEE
LEE
> <phi...@btinternet.com> wrote:
>
> >"Andre de Guerin" <mand...@gtonline.net> wrote in message
> >news:3a439009...@news.virgin.net...
> >> http://news.bbc.co.uk/hi/english/health/newsid_1080000/1080264.stm
> >>
> >> Good thing I bought that geiger counter .. :)
> >Yikes! Don't think my watch is contaminated tho' - it's a Zeon Tech
ZR13999.
> >Pity the rubber strap irritates my wrist :-(
> >
> >Anyone seen those old glow-in-the-dark clocks (the REALLY old ones)
that
> >used radon/radium (?) paint? Nasty... The closest thing to
radioactivity in
> >my watch is AFAIK either the lithium battery or the
electroluminescent (EL)
> >backlight panel.
>
> nothing .
> My smoke alarm set it a'clicking though, through the metal case .
>
> >
I can`t get any sort of reading from any of my smoke detectors and
can`t find a radium faced watch except in the antique shops. I did
manage to buy a small amount of yellow uranium oxide in Nevada but, the
small pieces only emit very low radiation levels..alphas, betas no
gammas. Lee
LEE
Iinterestingly, Many present day nuke warheads in storage contain
tritium (more neutrons when needed). The tritium levels (W-88,etc) must
be monitored and refreshed due to limited shelf life along with other
ddevice components. Lee. No, not the fired scientist!!
LEE
"DU" rounds do a great job on the A-10 gattling gun as they chew up
anything and everything. The DU M1A2 tank rounds do an even better job
of chewing up thick armor..or so Sadaam said :). LEE
Lenny
>
> opps
> forgot to attach the pdf..
> duh!
> hehe
>
> ]
> bob wrote in message ...
> Part 1.2 Type: Portable Document Format (application/pdf)
> Encoding: x-uuencode
My 1953 army truck has dashboard guages that glow in the dark for
blackout service. As previously mentioned, pity the poor girls who
licked the Radium paint brisles to point them. Its a great truck but not
my service vehicle. I don't drive it very much....Lenny Stein.
Nukie Poo
The glow is from fission fragments traveling through the medium faster than
the speed of light *in that medium* - water, in the case of a pool reactor.
A bare critical assembly - such as the types that killed Louis Slotin and
Henry Dahglin at Los Alamos - will emit a blue glow as the particles travel
through the air faster than the speed of light. The witnesses of accidental
criticality accidents have seen the eerie blue glow. There several other
such accidents in our nuclear history.
Depleted Uranium i.e. U238, will not emit any kind of glow as it cannot
attain criticality in any amount or geometry. U238 is not fissile although
it is fertile - that is can be converted to Neptonium239 and,
subsequentially, decays into Pu239 after a suitable sojourn as a blanket
material in an operating nuclear reactor and cooling pond. Depleted Uranium
is often used as projectiles as it is inert (nuclearwise) and denser than
lead. It is stockpiled in abundance as a by-product of enrichment plants.
Many nations have attempted to put it to greater use as blanket material in
fast breeder reactors with the plan to breed Pu239 for use as reactor fuel
proper.
"bob" <nom...@nospam.com> wrote in message
news:FF516.475$NA3.1...@paloalto-snr1.gtei.net...
tadchem
<snip>
> I can`t get any sort of reading from any of my smoke detectors and
> can`t find a radium faced watch except in the antique shops. I did
> manage to buy a small amount of yellow uranium oxide in Nevada but, the
> small pieces only emit very low radiation levels..alphas, betas no
> gammas. Lee
Native uranium oxide ("yellow cake") is isotopically 99.28% U-238, which
decays by both alpha (at 4.18 Mev) and gamma (0.045 Mev) modes
simultaneously. Gamma radiation is far more penetrating than alpha. It is
sometimes more difficult to detect because it doesn't interact with the
detector as efficiently as alpha.
Yellow cake also makes a brilliant and beautiful yellow glaze for ceramics.
Hard to find, though.
Tom Davidson
Brighton, CO
bob
sustain a chain reaction was around .3 something %.... modern DU may be .4
something %, so if my memory is correct you CAN sustain a chain reaction
with DU... you may need a whole hell of a lot of it, but it is possible...
Nukie Poo wrote in message <923a9n$eqg$1...@slb7.atl.mindspring.net>...
tadchem
> On Sat, 23 Dec 2000 01:29:11 -0500, "Charles W. Shults III"
> <aic...@gdi.net> wrote:
>
> > Depleted uranium is just that- depleted. The U-235 has been removed
and
> >it is barely more radioactive than the background. With a half-life in
the
> >billions of years, you aren't going to make anything glow with it. You
can
> >even buy the stuff from various vendors, such as Nuclear Metals. That's
> >where I get mine. It's great shielding for radioactive materials, even
> >better than lead.
>
> Isn't it more toxic than lead though ?
While LD-50 data for lead or uranium compounds are hard to find (no
controlled human LD-50 studies have been done), the minimum lethal dose will
depend on the solubility of the compound, the accumulated dose, and the mass
and metabolic rate of the patient, and probably some other factors that have
not been identified yet.
There is an additional hazard from uranium in that aspirated particulates
are radioactive and can contribute to lung cancer, even if they are
insoluble and never become truly absorbed into the body. Aspiration of
insoluble lead particulates has not been implicated in radiogenic cancers.
Soldiers are particularly prone to aspiration of insoluble uranium
particulates, as depleted uranium is used as a high-density core in
armor-piercing artillery rounds, where the INTENT is to blast the shell and
anything it impacts into smithereens. Just don't get caught downwind of it
without Class A respiratory protection against 1 micron particles.
Tom Davidson
Brighton, CO
Charles W. Shults III
of about 99.28% U-238 and 0.72% U-235. There is a trace of U-234 also, but
not much. This is pretty poor and does not support a chain reaction that
can yield useful power. It can be made to happen, but requires odd
conditions, like a huge amount of it and a moderator. Hafnium used to be
popular...
Enrichment occurs by concentrating the percentage of U-235. You can
also make nuclear fuel by converting U-238 to plutonium (through the
neptunium pathway) as was noted previously. When you remove U-235 from
natural uranium, you end up with "depleted" uranium, which is now down to
0.1% or less U-235. This material is a poor source of radioactivity.
bob wrote in message ...
>i thought the minimum isotopic concentration of 235 in 238 required to
>sustain a chain reaction was around .3 something %.... modern DU may be .4
>something %, so if my memory is correct you CAN sustain a chain reaction
>with DU... you may need a whole hell of a lot of it, but it is possible...
DU is depleted. It is less capable of a chain reaction that natural
uranium. And modern DU has -less- U-235 in it because methods of extraction
are better.
>Nukie Poo wrote in message <923a9n$eqg$1...@slb7.atl.mindspring.net>...
>>A bare critical assembly - such as the types that killed Louis Slotin and
>>Henry Dahglin at Los Alamos - will emit a blue glow as the particles
travel
>>through the air faster than the speed of light
^^^^^^^^^^^^ for
the medium, not faster than c!
(as noted previously)
I would rather stare at liquified ozone- the hazards would be far more
acceptable! But as I also noted previously, the assembly would be critical
and there is a good chance you would not see the flash. Or live to tell of
it.
Chris
$200 for a geiger counter, or I could buy a whole collection of glowing
watches... decisions decisions..
I think I'll opt for the watches... I'll just put them on my arm here...
hey, it's starting to itch... uh oh...
I'll keep my eyes open, but there aren't a lot of labs around here... so
stolen or legit... my odds on getting one used are slim... if only I can
figure out a reason to buy it other then just to fool around with... "honey,
happy aniversary!"
--
Chris
Remove .nospam to reply.
= = = =
His Excellency Majesty President
Field Marshal General Doctor
Tenured Professor Licensed
Electrician And Supreme Astronaut
= = = =
"LEE" <lee...@my-deja.com> wrote in message
news:922v3f$ij9$1...@nnrp1.deja.com...
Fleetie
> anything and everything. The DU M1A2 tank rounds do an even better job
> of chewing up thick armor..or so Sadaam said :). LEE
Yeah, what a cool 'plane! 4000 rounds/minute of 30mm calibre DU, isn't
it? yeoowch!
Apparently it can't shoot its entire load in one go, or it'd melt
the gun!
And what's with the SR71 being ditched in 1989 or whenever it was? Another
totally cool 'plane consigned to history. But is there a replacement? The
world wants to know!
Martin
---------------------------------------------------------------------------
M.A.Poyser Pleasure Precedes Pain Tel: 07967 110890
Fleetie
> blackout service. As previously mentioned, pity the poor girls who
> licked the Radium paint brisles to point them.
...And their boyfriends!
Sorry!
Chris
When they look out their windows, they both see Rubble!
Seriously, there's some controversy regarding DU rounds now, with some
saying that it may be part of "Gulf War" syndrome, and in addition, the
Aluminium casings and the slugs just fall and are left. Thousands upon
thousands lie in modern battlefields, and on the bottom of the oceans from
naval training exercises.
--
Chris
Remove .nospam to reply.
= = = =
His Excellency Majesty President
Field Marshal General Doctor
Tenured Professor Licensed
Electrician And Supreme Astronaut
= = = =
"LEE" <lee...@my-deja.com> wrote in message
news:9230p4$jpt$1...@nnrp1.deja.com...
> In article <t48h8te...@corp.supernews.com>,
Chris
mess... get rid of the non-y2k-ok missiles...
--
Chris
Remove .nospam to reply.
= = = =
His Excellency Majesty President
Field Marshal General Doctor
Tenured Professor Licensed
Electrician And Supreme Astronaut
= = = =
"LEE" <lee...@my-deja.com> wrote in message
news:92304r$jcn$1...@nnrp1.deja.com...
bob
> I would rather stare at liquified ozone- the hazards would be far more
>acceptable! But as I also noted previously, the assembly would be critical
>and there is a good chance you would not see the flash. Or live to tell of
>it.
these criticality accidents did not result in necisarily violent destruction
of the pit...
there were several pulsed reactors built back iont he day that were nothing
more than large chunks of highly enriched U or Pu.... godiva was one... i
cant remeber the names of others...
the amount of ebnergy released during these accidental criticalities is
directly proportional to how critical they went.... for example, if the mass
of fissile material was just barely crittical, then simple thermal expansion
of the mass could have been sufficent to reduce the multiplicaiton factor to
below unity..
just beacuse a critticality occurd does not mean there is going to be any
violent hapenings (orther than a tremendous amount of radiation)
bob
Fleetie wrote in message
<977627404.3097.0...@news.demon.co.uk>...
Charles W. Shults III
(at least) extreme thermal effects. There are a few critical reactors that
get the material right to the edge of such effects, and a recent development
was made of an old lawnmower engine and two sub-critical masses that were
positioned on the piston face and in the head.
When the piston extended into the head, the heat developed expanded the
air in the cylinder violently and caused it to run through what would appear
to be a normal "putt-putt" operation. This is a serious contender for
small, lightweight, dense energy generation that will easily rival most RTGs
in spacecraft! It can turn a generator and make electricity in the
conventional manner while using two masses of fissionable material as the
fuel source.
But observing any critical event can mean that you will die. As you
pointed out, that immense burst of radiation is enough to do it. Accidental
critical events are bad by definition. I'll still risk the liquid ozone
instead. I can then still choose to have more children. Or grow more hair.
kc8adu
painting radium watch/clock dials.
because of the death/illness it caused the place is a ghost town.
"Fleetie" <fle...@fleetie.demon.co.uk> wrote in message
news:977627669.3134.0...@news.demon.co.uk...
Chris
Gulf... but don't quote me on that.
--
Chris
Remove .nospam to reply.
= = = =
His Excellency Majesty President
Field Marshal General Doctor
Tenured Professor Licensed
Electrician And Supreme Astronaut
= = = =
"bob" <nom...@nospam.com> wrote in message
news:Bng16.1276$NA3.3...@paloalto-snr1.gtei.net...
rh...@megabits.net
Just curious. After "Desert Storm" Their was a lot of talk about some
of the health issues concerning our use of DU in some of our Armor
pierceing rounds. They claim to have established a link.
Bob
On Sat, 23 Dec 2000 01:29:11 -0500, "Charles W. Shults III"
<aic...@gdi.net> wrote:
> Depleted uranium is just that- depleted. The U-235 has been removed and
>it is barely more radioactive than the background. With a half-life in the
>billions of years, you aren't going to make anything glow with it. You can
>even buy the stuff from various vendors, such as Nuclear Metals. That's
>where I get mine. It's great shielding for radioactive materials, even
>better than lead.
>
bob
i was just ppointing out that one would surely be alive long enough to tell
about it..
even with a whole bost does of 1000 rem you will still be alive and kicking
for hours to days..
i cant imagein what kind of dose it would take to kill instantly..
i imagine it would be so high that the body functions simply stoped due to
thermal heating of tissue, ect....
Charles W. Shults III wrote in message ...
tadchem
<snip>
> And what's with the SR71 being ditched in 1989 or whenever it was? Another
> totally cool 'plane consigned to history. But is there a replacement? The
> world wants to know!
From http://www.abovetopsecret.com/sr71.html
On 6 March, 1990, the legendary SR-71 Blackbird was retired after Blackbird
(serial number 64-17972) shattered the official air speed record from Los
Angeles to Washington's Dulles Airport. The sudden discommissioning of the
aircraft with little opposition from the USAF stirred controversy over the
possibility of a successor aircraft, the Aurora.
(see http://www.abovetopsecret.com/aurora.html )
There were a couple exceptions...
From http://www.geocities.com/CapeCanaveral/Lab/3993/SR71.html
As of January 1st, 1997, two SR-71 air crews and planes were declared
mission ready for the first time since the plane's retirement. In 1994,
Congress appropriated funds to put two aircraft back into service, and these
airplanes were taken out of storage, refurbished, and delivered to the USAF.
Officially, the Aurora does not exist. There have been sightings of a
black, triangular craft including one by a trained aircraft spotter who
spotted a craft matching the description over Scotland being refueled by a
KC-135 tanker and escorted by a brace of F-111's
http://www.geocities.com/area51/atlantis/1545/aurora.html
Tom Davidson
Brighton, CO
Rich Grise
phosphor, until they decided that that was dangerous. I
do remember that Timex with the backlight, but I have a
tendency to guess that it was electroluminescent - the
watch probably took a dive because the batteries would
last about two days.
Merry Solstice!
Rich
William L. Bahn wrote:
>
> Depleted uranium? Yeah. Right.
>
> Tritium perhaps.
>
> ae2...@wayne.edu wrote in message ...
> >I used to have a radioactive writswatch! It was a Timex Nite-lite, made
> >around 1980. I think they only manufactured them for one year (for
> >obvious reasons). Had a pellet of depleted uranium in it for
> >backlighting. I wonder how they designed the electronics to survive in
> >such an environment?
Rich Grise
For awhile, they were also used in air ionizers (negative ions put
you in a good mood, and all that.)
Happy Solstice!
Rich
Charles W. Shults III wrote:
>
> You would have to eat it. Uranium is pyrophoric, meaning that it
> combusts readily in air. The dust (uranium oxide) is pretty toxic, but by
> itself, the metal tends to be fairly inert. Not like some other metals I
> can think of.
Nukie Poo
hi-quality magnetic phono cartridge that had a small piece of activated gold
foil glued on it just above the stylus for static discharging to help
prevent dust build-up. I believe it was a Grado moving coil or something
like that. It used to "really ring the bell" on my Geiger counter. I used
to keep it inside of an old Citroen suspension sphere that I had taken
apart. Even then it still would stimulate the counter as it gave off Gammas
as well as Betas. I sold it to some chap up at a antique radio meet in
Canandaigua years ago when my first kid came along (and, no he wasn't born
with any flippers or third eye!). I used to collect things like that - many
vacuum tubes have enough thorium in them to give a nice reading. Fiestaware
is another great source.
"Rich Grise" <rich...@vel.net> wrote in message
news:3A46BA...@vel.net...
Andre de Guerin
>
>Andre de Guerin wrote in message <3a44aea4...@news.virgin.net>...
>>On Fri, 22 Dec 2000 18:53:01 -0500, "Nukie Poo" <paul...@sprynet.com>
>>wrote:
>>
>>>From scrap steel contamination. An old Cobalt therapy machine could've
>>>entered a scrap facility. It has happened several times before. I
>remember
>>>the radioactive school chair legs incident as well as a Mexican kid who
>>>found a Cs137 capsule in a junk yard and took it home and set it on the
>>>mantle. It turned some of the crystal that was on display black and
>killed
>>>everyone in the house one by one.
>>
>>There was another incident where a machine's source got melted down
>>with some scrap steel to make rebars that were then used in people's
>>houses ! I
> well at ;least the radioactivity would be sheiulded by the concrete int he
>house..
Not really, Co-60 is a high energy gamma emitter that gets through
everything except lead .
The radiotherapy machines I have read about use a massive lead block
with a lead window or a mechanism which moves the source and block of
lead to the window . Either way in the non-emitting configuration it
is VERY well shielded unelss someone tries to melt down the lead
shield . (this nearly happened a few years ago, two people stole a
Co-60 source from a metal-working plant for the lead) ... !
>
>
>
Andre de Guerin
<aic...@gdi.net> wrote:
> Unless criticality is monitored and/or controlled, it usually results in
>(at least) extreme thermal effects. There are a few critical reactors that
>get the material right to the edge of such effects, and a recent development
>was made of an old lawnmower engine and two sub-critical masses that were
>positioned on the piston face and in the head.
> When the piston extended into the head, the heat developed expanded the
>air in the cylinder violently and caused it to run through what would appear
>to be a normal "putt-putt" operation. This is a serious contender for
>small, lightweight, dense energy generation that will easily rival most RTGs
>in spacecraft! It can turn a generator and make electricity in the
>conventional manner while using two masses of fissionable material as the
>fuel source.
Pretty clever ; what happens if it gets jammed in the "full extended"
position ? I've got a pretty good idea, (BIG BOOM) ...
Andre de Guerin
>In article <3a439009...@news.virgin.net>,
> mand...@gtonline.net (Andre de Guerin) wrote:
>> http://news.bbc.co.uk/hi/english/health/newsid_1080000/1080264.stm
>>
>> Good thing I bought that geiger counter .. :)
BTW I read a good (totally true) story in Reader's Digest entiled "The
Radioactive Boy Scout" , concerning a kid who built his own model
breeder reactor using smoke alarm parts, lamp mantles and radium paint
from clocks .. ! apparently the NRC had to come and clear up the
(radioactive) mess .
The darn thing actually worked too !!! -he'd concentrated the thorium
from the lamp mantles using lithium from some batteries, then mixed it
with the concentrated and dried radium paint and wrapped the thing in
tinfoil . Radiation was several times background .
Cops that caught him trying to dump it (he figured that "too much
radioactive stuff was in one place) thought it was a nuke !!
Apparently he now works for the Government in one of their labs .. !
>>
>
>
>
>Cobalt 60 contaminated wristbands...YUK!!! Alphas,betas,gammas, high
>speed electrons...Beta burns can disturb one!! Alphas can be stopped
>with a piece of paper. Don`t eat any R active particles as they
>gravitate to certain parts of the body and cause ionizing damage.
> Always have your calibrated survey meter/geiger counter at the ready.
>
>LEE
Andre de Guerin
<aic...@gdi.net> wrote:
> This still does not make sense. The chip is in black epoxy or ceramic.
>Light itself should have no effect on it, with or without the reflector.
>Therefore, it must be something other than light.
> Consider that a flash tube uses high voltages and a fast switching time.
>You are probably generating a tiny EMP that causes the effect when the tube
>is very close. Try the following experiment.
> Cover the watch with an opaque shield (but not metal foil) and trigger
>the flash tube. It should still cause the same effect. Try a couple of
>sheets of black construction paper and black plastic film.
I'll have to try my Mark 2 camera flash (12 tubes, driven by 160 uF
330V caps, flashed simultaneously .)
Problem is getting the 330 uF at several millamps needed to charge all
the caps . I've already figured out how to flash all the tubes at once
(using a board full of photoflash transformers) ... trouble is I
haven't built it yet .
I've also got to add a status display, neons would work OK for this .
Andre de Guerin
wrote:
>In the way old days, watches had radium, and some suitable
>phosphor, until they decided that that was dangerous. I
>do remember that Timex with the backlight, but I have a
>tendency to guess that it was electroluminescent - the
>watch probably took a dive because the batteries would
>last about two days.
This has subsequently been fixed .
I think they used an HV825 chip (ultra efficient) instead of a
transistor based step-up circuit .
tadchem
"Nukie Poo" <paul...@sprynet.com> wrote in message
news:926kbk$nd4$1...@nntp9.atl.mindspring.net...
> Yes Rich, and also those photo lens dust removal brushes. I once had an
old
> hi-quality magnetic phono cartridge that had a small piece of activated
gold
> foil glued on it just above the stylus for static discharging to help
> prevent dust build-up. I believe it was a Grado moving coil or something
> like that. It used to "really ring the bell" on my Geiger counter. I
used
> to keep it inside of an old Citroen suspension sphere that I had taken
> apart. Even then it still would stimulate the counter as it gave off
Gammas
> as well as Betas. I sold it to some chap up at a antique radio meet in
> Canandaigua years ago when my first kid came along (and, no he wasn't
born
> with any flippers or third eye!). I used to collect things like that -
many
> vacuum tubes have enough thorium in them to give a nice reading.
Fiestaware
> is another great source.
When I was a Radiation Safety Officer, I gave annual briefings to all the
other employees to let them know just what the radiation hazard symbols were
all about. We had 23 detector cells for gas chromatographs that used
titanium foil impregnated with tritium scattered all around the plant and
the labs. Part of the talk was meant to reassure them that they were not
personally being exposed to any radiation.
I would place a detector cell right against the end of the "wand" on my
survey meter (a Geiger-Mueller type tube) and there would be no response. I
would then replace the detector cell with a woven glass mantle from a
Coleman lantern and there would be a faint but noticeable response (the
mantles are thoriated).
Then I would take the meter over towards another table where I had placed a
large metal box with a hazard label. The meter would start to respond
strongly about 2 meters away from the table, and I could track down the
source of the radiation to a single spot on the box. I would then open the
box to reveal an antique (black crinkle finish) photographic darkroom timer
with a face painted with radium paint.
Finally, I would walk up and down the aisles and scan the attendees. I
found one gentleman who had an old wristwatch with radium paint which he had
been wearing for years. He even wore it after he retired.
Tom Davidson
Brighton, CO
tadchem
<snip>
> BTW I read a good (totally true) story in Reader's Digest entiled "The
> Radioactive Boy Scout" , concerning a kid who built his own model
> breeder reactor using smoke alarm parts, lamp mantles and radium paint
> from clocks .. ! apparently the NRC had to come and clear up the
> (radioactive) mess .
>
> The darn thing actually worked too !!! -he'd concentrated the thorium
> from the lamp mantles using lithium from some batteries, then mixed it
> with the concentrated and dried radium paint and wrapped the thing in
> tinfoil . Radiation was several times background .
>
> Cops that caught him trying to dump it (he figured that "too much
> radioactive stuff was in one place) thought it was a nuke !!
>
> Apparently he now works for the Government in one of their labs .. !
A fascinating story! When I first heard it the comment was made in the NRC
bulletin that he had nearly collected the entire periodic table!
http://www.readersdigest.com/rdmagazine/specfeat/archives/taleoftheradioacti
veboyscout.htm
Sounds to me like he's too clever to work for the government, though. He's
barely 20 years old now; he did all this when he was 14-15.
Tom Davidson
Brighton, CO
Martin Brown
dwight_...@my-deja.com wrote:
> In article <3A43BDED...@pandora.be>,
> martin...@pandora.be wrote:
> > >
> > Seems unlikely - most used tritium and a fluorescer in that era. It
> was
> > quite easy to convert a normal digital watch by adding tritiated
> fishing
> > floats behind the display. One minor side effect was that the whole
> > electronics could then be reset by exposure to strong sunlight or a
> > flashgun....
>
> I agree that it was most likely tritium but what does
> a flashgun or sunlight have to do with reseting the electronics?
There wasn't a lot of room in them, and the partially exposed clock chip
was slightly photosensitive. Well made ones didn't have this problem -
home made ones did.
Regards,
Martin Brown
bob
this hardly clasifies as a model breeder reactor.... unless he added some
beryllium in there he didnt get any nuetrons to turn the thorium into
anything sexy.. all he did was assemble a big pile of radioactive material..
that doesnt take smarts, it takes stupidity in my book
Andre de Guerin wrote in message <3a464de6...@news.virgin.net>...
bob
just alo of nuetrons and some thermal energy..
just such an accident ook place with one of the pulsed reactors... the
fissile assembly was damaged due to thermal stress (aparently it either
cracked or started to melt) one the mass was deforemd the change of shape
stoped the reaction and all went back to normal....
potential yeild form the assembly of a critticle mass is strongly dependant
on the amount of masses over a criticle mass you have.. in all these cases
since the core was assembled through normaly mechanical means (ie not form
an explosion) it would have only been practicle to make a just barely over
critticle mass, therfore the energy ramp up from the fiffion is slow enough
to not have the mass explosivly disaseble, but simplky destroy it's self
viam more traditional methods, again melting or rupturing from thermal
stress...
Andre de Guerin wrote in message <3a4609ba...@news.virgin.net>...
Andre de Guerin
<tadche...@earthlink.net> wrote:
>
>"Fleetie" <fle...@fleetie.demon.co.uk> wrote in message
>news:977627404.3097.0...@news.demon.co.uk...
>
><snip>
>
>> And what's with the SR71 being ditched in 1989 or whenever it was? Another
>> totally cool 'plane consigned to history. But is there a replacement? The
>> world wants to know!
>
>
>From http://www.abovetopsecret.com/sr71.html
>On 6 March, 1990, the legendary SR-71 Blackbird was retired after Blackbird
>(serial number 64-17972) shattered the official air speed record from Los
>Angeles to Washington's Dulles Airport. The sudden discommissioning of the
>aircraft with little opposition from the USAF stirred controversy over the
>possibility of a successor aircraft, the Aurora.
>(see http://www.abovetopsecret.com/aurora.html )
>
>There were a couple exceptions...
>
>From http://www.geocities.com/CapeCanaveral/Lab/3993/SR71.html
>As of January 1st, 1997, two SR-71 air crews and planes were declared
>mission ready for the first time since the plane's retirement. In 1994,
>Congress appropriated funds to put two aircraft back into service, and these
>airplanes were taken out of storage, refurbished, and delivered to the USAF.
According to my (highly classified-delete before reading) documents,
The Aurora (or to give its real name, the XB-182 ) is a high altitude
reconnisance stealth aircraft employing plasma based visual and radar
stealth capabilities (i.e. invisible) ; this plasma system also
reduces drag by an insane amount (32%) at Mach 2 and above , allowing
it to cruise at high altitude for up to 24 hours at a time without
refuelling . (typical ceiling=125,000 feet) .
The primary propulsion system is a pulse wave detonation engine .
This is the part everyone already knows about .
What is not so well known is that it gets its oxygen direct from the
surrounding air by using a superconducting magnet to separate the
oxygen from the incoming air flow, therefore reducing the amount of
fuel required on board and hence a substantial weight reduction .
This can work because of the extreme altitude the aircraft operates at
so less cooling is required ; part of the LOX stored on board is used
to cool the magnet which operates at a Tc of 192 Kelvins using a
bismuth tantalum copper oxide based superconductor .
This magnet also helps to generate the powerful magnetic field
required to sustain the plasma .
BTW the prototype for this technology was used on the B1-B , to reduce
drag by charging the leading edges of the wing to reduce drag .
Philip Pemberton
>
> >In article <3a439009...@news.virgin.net>,
> > mand...@gtonline.net (Andre de Guerin) wrote:
> >> http://news.bbc.co.uk/hi/english/health/newsid_1080000/1080264.stm
> >>
> >> Good thing I bought that geiger counter .. :)
>
> BTW I read a good (totally true) story in Reader's Digest entiled "The
> Radioactive Boy Scout" , concerning a kid who built his own model
> breeder reactor using smoke alarm parts, lamp mantles and radium paint
> from clocks .. ! apparently the NRC had to come and clear up the
> (radioactive) mess .
and a load of old smoke detectors, pinched the americium from the detectors
and but it into a lead block. Very nasty.
> The darn thing actually worked too !!! -he'd concentrated the thorium
> from the lamp mantles using lithium from some batteries, then mixed it
> with the concentrated and dried radium paint and wrapped the thing in
> tinfoil . Radiation was several times background .
Nasty...
> Cops that caught him trying to dump it (he figured that "too much
> radioactive stuff was in one place) thought it was a nuke !!
I would too if I put a Geiger counter near it and ended up with a high
reading.
> Apparently he now works for the Government in one of their labs .. !
Building atom bombs? Smeggin' hell...
--
Phil.
http://www.philpem.f9.co.uk/
phi...@bigfoot.com
Andre de Guerin
>very true
>i was just ppointing out that one would surely be alive long enough to tell
>about it..
>even with a whole bost does of 1000 rem you will still be alive and kicking
>for hours to days..
>i cant imagein what kind of dose it would take to kill instantly..
>i imagine it would be so high that the body functions simply stoped due to
>thermal heating of tissue, ect....
Exposure to enough radiation WILL result in irreversible loss of
consciousness due to disruption of neural proteins .
BTW this is an immediate effect IIRC .
Andre de Guerin
>no big boom..
>just alo of nuetrons and some thermal energy..
>just such an accident ook place with one of the pulsed reactors... the
>fissile assembly was damaged due to thermal stress (aparently it either
>cracked or started to melt) one the mass was deforemd the change of shape
>stoped the reaction and all went back to normal....
Criticality accidents are REALLY nasty ; there was nearly an
accidental nuclear detonation back in 1944 when someone at Los Alamos
was trying to determine the critical mass using two sub-critical
masses on rollers and two screwdrivers; they got too close together
and became critical , witnesses (those who survived that is) state
that "there was a bright blue glow from the masses" just before
the person doing the experiment ripped the two masses apart to prevent
an explosion .. !
Something similar happened in Japan recently when nuclear workers put
too much uranium solution into a container so it got higher than the
specially shaped (flat) bottle designed to prevent a criticality and
it went critical, irradiating several workers .
The other way this can happen is in reactors that use a liquid
moderator/coolant (e.g. water) ; if there is a loss of coolant then
the reactor goes supercritical and melts down .
Examples - Russian submarine reactors .
This can also happen if air gets into the moderator, forming a bubble
which has the same effect as loss of coolant .
BTW if the pressure in the coolant loop gets too low then the water
can turn to steam with a similar effect .
Most new reactors are designed to withstand this type of failure,
using multiple redundant backups as well as designing the reactor
geometry so that loss of coolant will cause reactor shut-down .
(still have to cool it down but at least it won't meltdown) ..
Sam Goldwasser
a microscopic amount americium(sp?) in there.
--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html
Nukie Poo
can see he did not build a reactor - just a neutron source with alpha
emitters and Beryllium which was being done in the early part of the 20th
century by the Curies et al.
http://www.bullatomsci.org/issues/1999/jf99/jf99bulletins.html
"tadchem" <tadche...@earthlink.net> wrote in message
news:BLH16.10280$3B5.2...@newsread2.prod.itd.earthlink.net...
Sam Goldwasser
The amount of radioactive material in a smoke detector or lamp mantel or
radium watch is microscopic. Even a pile of them would result in a minute
quantity of radioactive material, not anywhere near critical mass of anything.
Using lithium from batteries for processing? Metallic lithium is about
the nastiest stuff imaginable. This sounds more like a MacGuyver episode
than a serious piece.
And "several times background"? Heck, get close to any radioactive source,
even a microscopic one, and you will have that!
We all know that Reader's Digest is a refereed scientific journal, right. ;)
It was in Reader's Digest, must be true!
--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html
In article <9282ua$837$1...@neptunium.btinternet.com> "Philip Pemberton" <phi...@btinternet.com> writes:
Path: nntp.upenn.edu!info1.fnal.gov!newsfeed.stanford.edu!news.tele.dk!193.190.198.17!newsfeeds.belnet.be!news.belnet.be!btnet-peer1!btnet-feed5!btnet!mendelevium.btinternet.com!not-for-mail
From: "Philip Pemberton" <phi...@btinternet.com>
Newsgroups: alt.lasers,sci.electronics.misc,alt.sci.physics,sci.electronics.repair
Date: Mon, 25 Dec 2000 18:19:26 -0000
Organization: BT Internet
Lines: 39
References: <3a439009...@news.virgin.net> <920e5f$qlj$1...@nnrp1.deja.com> <3a464de6...@news.virgin.net>
NNTP-Posting-Host: host62-7-43-66.btinternet.com
X-Priority: 3
X-MSMail-Priority: Normal
X-Newsreader: Microsoft Outlook Express 5.50.4133.2400
X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400
Xref: nntp.upenn.edu alt.lasers:5368 sci.electronics.misc:88426 sci.electronics.repair:231314
bob
the only radiation accident that I have ever hurd of was when a few workers
were removing an acces port to an undergroud high level liquid storage tank.
aparently the tank was monitored by two tubes, a 'dip tube' alowing for
liquid to be drawn off, and a purge tube, that controlled pressureization of
the tank. aparently the pressurization tube was somehow cloged, so as soobn
as the last bolt on the inch or so thick stainless well cal was broken free,
the whole assembly was blown off by a geiser of high level waste. the amount
of radiation these poor suckers were exposed to was enough to partially
polymerize their bodies, so that they needed to be cut open with a saw to be
autopsied.... i can only imagine what kind of expose that required though!
Andre de Guerin wrote in message <3a47b5cd...@news.virgin.net>...
bob
>Criticality accidents are REALLY nasty ; there was nearly an
>accidental nuclear detonation back in 1944 when someone at Los Alamos
>was trying to determine the critical mass using two sub-critical
>masses on rollers and two screwdrivers; they got too close together
>and became critical , witnesses (those who survived that is) state
>that "there was a bright blue glow from the masses" just before
>the person doing the experiment ripped the two masses apart to prevent
>an explosion .. !
the energy liberated in an atomic explosion occurs in the order of
microseonds... a person can not rip a criticle mass apart in time to avoid
major energy release... but thats my who point, things happen so quickly
that with conventional means two pieces of critticle material will destroy
themselfes before much more than a single critticle mass can be acheived, so
it isnt possible to realeas a hugh amount of energy in such an accident...
>The other way this can happen is in reactors that use a liquid
>moderator/coolant (e.g. water) ; if there is a loss of coolant then
>the reactor goes supercritical and melts down .
>Examples - Russian submarine reactors .
a pile is has the least critticle mas, thus the highest chance for
criticality WITH a moderator present, not without... therefore if you ahve
loss of coloant, the fuel must have been criticle befiore..all the loss of
fuel does is prevent the reactor for being cooled, and therefore melt
dowqn.. it doesnt cause the criticality it's self.. unless they are putting
boron or cadmium in the water...
bob
>According to my (highly classified-delete before reading) documents,
>The Aurora (or to give its real name, the XB-182 ) is a high altitude
>reconnisance stealth aircraft employing plasma based visual and radar
>stealth capabilities (i.e. invisible) ; this plasma system also
>reduces drag by an insane amount (32%) at Mach 2 and above , allowing
>it to cruise at high altitude for up to 24 hours at a time without
>refuelling . (typical ceiling=125,000 feet) .
>
>The primary propulsion system is a pulse wave detonation engine .
>This is the part everyone already knows about .
>
>What is not so well known is that it gets its oxygen direct from the
>surrounding air by using a superconducting magnet to separate the
>oxygen from the incoming air flow, therefore reducing the amount of
>fuel required on board and hence a substantial weight reduction .
>This can work because of the extreme altitude the aircraft operates at
>so less cooling is required ; part of the LOX stored on board is used
>to cool the magnet which operates at a Tc of 192 Kelvins using a
>bismuth tantalum copper oxide based superconductor .
>This magnet also helps to generate the powerful magnetic field
>required to sustain the plasma .
>
>BTW the prototype for this technology was used on the B1-B , to reduce
>drag by charging the leading edges of the wing to reduce drag .
you arent serious are you??
hitting the egg nog a bit too much tonight???
would you care to provide me a refrence for the Bi based superconductor
system....
current Bi systems have a Tc of around 100K.. there are some other systems
with Tc's of close to 150 K but their Hc and Jc is disnally low, meaning
they cxan not be used for a practicle superconducting magnet.... if there
was a sytem with a Tc of nearly 200 K it would be in use NOW.... we are
tlaking about a market of probably hundreds of billions annualy through out
the globe.. i dont care if the military has come up with some ultra
classified HTc superconductor, they wouldnt keep it under wraps.. they would
pattent it and rake int he $$$$.. once the technology was developed they
could probably double their defense budget with the procceds..... every
single power tansmission line, generators mag lev trains, squids, mri
magnets... all would be obsoleted by a high Tc, Jc, Hc superconductor,
because at these tempertures one could use a relativly inexpensiuve freon
based refrigerant suystem instead of liquid cryogens...
visiual stealth capibilities with plasma??
you have been watching too much star trek.. no??
Charles W. Shults III
dosages are listed by category and for exposures of 25 to 100 rems whole
body exposure, there are nothing but blood changes and people so exposed can
continue to work.
For doses of 100 to 200 rems, there should be slight or no illness.
Some nausea or vomiting on the first day in some of those exposed, with a
latent period of up to two weeks with no signs of illness. After that, mild
malaise or loss of appetite may reappear.
For doses of 200 to 1000 rems, survival is possible, but not likely for
the upper end of the exposure. As before, the first symptoms appear in the
first day or two, but more severe. These are nausea, vomiting, loss of
appetite, diarrhea and malaise. After the first day or two, the symptoms
disappear and are latent for up to two weeks. After they return, there may
be a step-like increase in temperature as infections set in. After two to
three weeks, spontaneous bleeding can occur from some organs or from under
the skin as hemorrhages (called petechia). Loss of clotting and
susceptibility to infection will follow.
I'll skip the details here.
For doses of 1000 rems and up, survival is improbable. They result in
changes to the central nervous system. There are symptoms of
hyperexcitability, ataxia, respiratory distress and intermittent stupor.
There is almost immediate incapacitation and death is certain in a few hours
to a week following the exposure. Between 1000 and 5000 rems, intestinal
bleeding is common. Vomiting, nausea, prostration, diarrhea, and anorexia
follow. There may be no pain during the first few days (if they last that
long). And latent symptoms are returning in 2 to 3 days instead of two
weeks. Then the early symptoms return, followed by delerium or coma. Death
may take two days to a week.
From that, you can get a general idea of how things proceed at higher
doses.
Andre de Guerin
<phi...@btinternet.com> wrote:
>"Andre de Guerin" <mand...@gtonline.net> wrote in message
>news:3a464de6...@news.virgin.net...
>> On Fri, 22 Dec 2000 20:39:11 GMT, LEE <lee...@my-deja.com> wrote:
>>
>> >In article <3a439009...@news.virgin.net>,
>> > mand...@gtonline.net (Andre de Guerin) wrote:
>> >> http://news.bbc.co.uk/hi/english/health/newsid_1080000/1080264.stm
>> >>
>> >> Good thing I bought that geiger counter .. :)
>>
>> BTW I read a good (totally true) story in Reader's Digest entiled "The
>> Radioactive Boy Scout" , concerning a kid who built his own model
>> breeder reactor using smoke alarm parts, lamp mantles and radium paint
>> from clocks .. ! apparently the NRC had to come and clear up the
>> (radioactive) mess .
>I remember reading that one. Very interesting. IIRC he got a chemistry book
>and a load of old smoke detectors, pinched the americium from the detectors
>and but it into a lead block. Very nasty.
Talking about nuclear shenannigans, I heard that a student over in the
USA built a DIY nuke using plans he got from the college library, then
used it as a coffee table . (no nuclear material though, just the
explosive lenses and the other parts inc. the neutron gun) .
>
>> The darn thing actually worked too !!! -he'd concentrated the thorium
>> from the lamp mantles using lithium from some batteries, then mixed it
>> with the concentrated and dried radium paint and wrapped the thing in
>> tinfoil . Radiation was several times background .
>Nasty...
>
>> Cops that caught him trying to dump it (he figured that "too much
>> radioactive stuff was in one place) thought it was a nuke !!
>I would too if I put a Geiger counter near it and ended up with a high
>reading.
I'd have put it in a lead box if it was me :)
BTW I haven't got anything very radioactive (except a couple of dead
smoke alarms) so I can't be sure my detector is calibrated .
Needs new tubes really, they are iodine quenched (read-old) and the
modern equivalents are much more sensitive and last longer .
>
>> Apparently he now works for the Government in one of their labs .. !
>Building atom bombs? Smeggin' hell...
Unlikely, these days they have a bigger problem maintaining their old
nukes, as the tritium used has a rather short half life so constantly
needs replacement . Also other essential components (e.g. the shaped
charges, electronic safety devices to prevent accidental detonation)
need regular checking .
One of the reasons why the US (and other) governments are so paranoid
about lost nukes is that if they are somewhere inaccessible (like in a
sunken nuclear submarine) then these components could degrade and
cause the nuke to fizzle . (possibly) releasing radiation into the
sea .
Not to mention that they leak BIG time once the outer casing corrodes
away . Not good for the environment .. !
Andre de Guerin
>
>>According to my (highly classified-delete before reading) documents,
>>The Aurora (or to give its real name, the XB-182 ) is a high altitude
>>reconnisance stealth aircraft employing plasma based visual and radar
>>stealth capabilities (i.e. invisible) ; this plasma system also
>>reduces drag by an insane amount (32%) at Mach 2 and above , allowing
>>it to cruise at high altitude for up to 24 hours at a time without
>>refuelling . (typical ceiling=125,000 feet) .
>>
>>The primary propulsion system is a pulse wave detonation engine .
>>This is the part everyone already knows about .
>>
<snip deranged waffle>
>>
>>BTW the prototype for this technology was used on the B1-B , to reduce
>>drag by charging the leading edges of the wing to reduce drag .
>
>you arent serious are you??
Not about the "classified" superconductor, but the rest is likely
true (based on what I have read in various magazines, especially the
plasma based drag reduction system) .
BTW the article in question gave a few subtle hints that the plasma
drag reduction may already be used in military aircraft .
(officially it is still in the experimental stages) .. :)
BTW I don't know if anyone has ever tried using tantalum in *any*
superconductor to date, but you never know .. the YBaCuO based one was
discovered by accident so someone in some lab somewhere might be
working on it .. ?
A discussion with someone at college led me to believe that certain
combinations of elements have not been tested because "they won't
work" according to currently accepted theories . Of course, no-one has
explained high temperature superconductivity yet (there are theories
but they don't cover all the observations) .
BTW I also read somewhere that Bi-Mg-Zn based superconductor may also
be a potential new superconductor but no-one has got the right
formula. (Yet) .
>hitting the egg nog a bit too much tonight???
>would you care to provide me a refrence for the Bi based superconductor
>system....
I read somewhere that a variant of YBaCuO doped with fluorine had a
critical temperature in excess of 200 kelvins, but couldn't be
reproduced. Maybe some trace impurity ??? !
Someone REALLY ought to try randomly adding a few percent of various
exotic elements to known superconductors just to see what happens ...
>current Bi systems have a Tc of around 100K.. there are some other systems
>with Tc's of close to 150 K but their Hc and Jc is disnally low, meaning
>they cxan not be used for a practicle superconducting magnet.... if there
>was a sytem with a Tc of nearly 200 K it would be in use NOW.... we are
>tlaking about a market of probably hundreds of billions annualy through out
>the globe.. i dont care if the military has come up with some ultra
>classified HTc superconductor, they wouldnt keep it under wraps.. they would
>pattent it and rake int he $$$$.. once the technology was developed they
>could probably double their defense budget with the procceds..... every
>single power tansmission line, generators mag lev trains, squids, mri
>magnets... all would be obsoleted by a high Tc, Jc, Hc superconductor,
>because at these tempertures one could use a relativly inexpensiuve freon
>based refrigerant suystem instead of liquid cryogens...
>
>visiual stealth capibilities with plasma??
>you have been watching too much star trek.. no??
This is possible according to the article I read, although a really
large power source would be required ...
>
>
>
Sorry about that in case I misled anyone - just got fed up with
deranged waffle about what they are up to in Area 51, so decided to
write something plausible that *might* be what is being tested at the
moment . :)
Andre de Guerin
wrote:
>Sorry, this sounds like some writer got carried away just a bit.
>
>The amount of radioactive material in a smoke detector or lamp mantel or
>radium watch is microscopic. Even a pile of them would result in a minute
>quantity of radioactive material, not anywhere near critical mass of anything.
He wasn't trying to make a critical mass, the idea was to irradiate
thorium (from the lamp mantles) to make uranium 233 (which is
fissionable) .
He then tried the same trick with radium , which did work .
bob
>This is possible according to the article I read, although a really
>large power source would be required ...
even if you cover something with a plasma there is still going to be visable
light opaque material under the plasma....
light is still going to be stoped and you are still going to see something
flying around in the air....
i to have hurd speculations that plasma is being used to block radar
refelction, but this seems highly unlikely for any craft that isnt a few
hundred km up... there is just too much atmosphere ate the altiudes planes
normally fly at, and way too much surface area to ionize.. not to mention
the fact that you would have to insulate the aircract with sacrificial tiles
like on the shuttle, do to the heat transfered from the plasma at such
densitys....
you would end up with a plane that needed a 1 gw nuclear reactor for power,
and had an few hundred extra thousand pounds of weight for insulartion..
i dont think it will fly..
bull...@gru.net
>very true
>i was just ppointing out that one would surely be alive long enough to tell
>about it..
>even with a whole bost does of 1000 rem you will still be alive and kicking
>for hours to days..
>i cant imagein what kind of dose it would take to kill instantly..
>i imagine it would be so high that the body functions simply stoped due to
>thermal heating of tissue, ect....
>
About 5000 REM will kill instantly from damage to the nervous system.
>Charles W. Shults III wrote in message ...
>> Unless criticality is monitored and/or controlled, it usually results
>in
>>(at least) extreme thermal effects. There are a few critical reactors that
>>get the material right to the edge of such effects, and a recent
>development
>>was made of an old lawnmower engine and two sub-critical masses that were
>>positioned on the piston face and in the head.
>> When the piston extended into the head, the heat developed expanded the
>>air in the cylinder violently and caused it to run through what would
>appear
>>to be a normal "putt-putt" operation. This is a serious contender for
>>small, lightweight, dense energy generation that will easily rival most
>RTGs
>>in spacecraft! It can turn a generator and make electricity in the
>>conventional manner while using two masses of fissionable material as the
>>fuel source.
>> But observing any critical event can mean that you will die. As you
>>pointed out, that immense burst of radiation is enough to do it.
>Accidental
>>critical events are bad by definition. I'll still risk the liquid ozone
>>instead. I can then still choose to have more children. Or grow more
>hair.
>>
Andre de Guerin
wrote:
>Sorry, this sounds like some writer got carried away just a bit.
>
>The amount of radioactive material in a smoke detector or lamp mantel or
>radium watch is microscopic. Even a pile of them would result in a minute
>quantity of radioactive material, not anywhere near critical mass of anything.
>Using lithium from batteries for processing? Metallic lithium is about
>the nastiest stuff imaginable.
There are more reactive elements (e.g. fluorine) ...
IIRC they dissolve uranium in hydrofluoric acid to get uranium
hexafluoride solution - it has to be stored in PTFE lined containers
as HF will dissolve glass .. !!
tadchem
"bob" <nom...@nospam.com> wrote in message
news:nAL16.265$jr3....@paloalto-snr1.gtei.net...
> americium, radium, and thorium all mixed together??
> this hardly clasifies as a model breeder reactor.... unless he added some
> beryllium in there he didnt get any nuetrons to turn the thorium into
> anything sexy.. all he did was assemble a big pile of radioactive
material..
> that doesnt take smarts, it takes stupidity in my book
He had a friend steal some beryllium from the school science lab.
Read the whole story at
http://www.readersdigest.com/rdmagazine/specfeat/archives/taleoftheradioacti
veboyscout.htm
Tom Davidson
Brighton, CO
tadchem
<snip>
> BTW I also read somewhere that Bi-Mg-Zn based superconductor may also
> be a potential new superconductor but no-one has got the right
> formula. (Yet) .
From http://www.coasttocoastam.com/rosreprt.html (Formerly the "Art Bell"
website): allegedly from a report on the analysis of pieces collected from a
UFO crash in Roswell, NM
"Energy dispersive spectroscopy (EDS) revealed the the shiny side contained
more than 95% magnesium (Mg) and a small amount (2-3%) of zinc (Zn) (Fig.
1). The dark side contained a significant amount of bismuth (Bi) (Fig. 2). "
...suggesting a *structured* combination of two metals (Mg and Bi) which
normally have nothing to do with each other.
?-)
Tom Davidson
Brighton, CO
tadchem
<snip>
> i to have hurd speculations that plasma is being used to block radar
> refelction, but this seems highly unlikely for any craft that isnt a few
> hundred km up... there is just too much atmosphere ate the altiudes planes
> normally fly at, and way too much surface area to ionize.. not to mention
> the fact that you would have to insulate the aircract with sacrificial
tiles
> like on the shuttle, do to the heat transfered from the plasma at such
> densitys....
> you would end up with a plane that needed a 1 gw nuclear reactor for
power,
> and had an few hundred extra thousand pounds of weight for insulartion..
> i dont think it will fly..
I heard speculation back in the 60's that induction of a high positive
voltage at the leading edge of an airfoil coupled with the opposite voltage
at the trailing edge would establish a corona discharge in the airfoil
boundary layer, turning the entire airfoil into a shaped and captive "ball
lightning".
The speculation was that this would result in an accelerated and attenuated
boundary layer, as the positive ions would be repelled by the conductive
surface of the leading edge drawn to the trailing edge by the negative
voltage there, reducing the aerodynamic drag.
This would effectively wrap the airfoil in a lower pressure bubble, also
contributing to reduced drag and increased efficiency.
Incidentally, the plasma would prevent radar (and other EM wavelengths!)
from reflecting off the surface of the airfoil.
I don't know if these experiments in "electrostatic propulsion" were ever
conducted.
Tom Davidson
Brighton, CO
Eric Katt
: "Andre de Guerin" <mand...@gtonline.net> wrote in message
: news:3a489ec2...@news.virgin.net...
: <snip>
: ?-)
[ Yes, I know that this doesn't belong here in these ngs ]
While I wouldn't have a clue as to its makeup - on 12/22/92 - I and a
friend saw a medium sized saucer-shaped craft just SE of Fergus Falls, MN
about 200 feet away hovering about 50 feet off the ground. A "balanced"
glow of an amber red color was emanating evenly from 4 rounded-edged
squarish panels on the bottom of the craft. There was an upraised portion
on the top of the craft. Viewing time was around 6-6:30 am for about 3-5
minutes. The craft was ~40' across.
Craft had originally been sighted from about a mile off - drifting from
the SW to the NE of the road we were on. Craft was also originally
'covered' in a bright bright glow. By the time it had crossed the road
and 'stopped' in the air - the glow had subsided revealing the craft with
two glowing 'points' on opposite edges of its diameter. The points seemed
to be of the same "color" of the originall bright glow. The color didn't
seem to be any bulb type of which I'm familiar - no Hg vapor blue ring
glow and no sodium yellow.
Weather was cold and windy - 10-20 mph perhaps. I'd stopped the car to
get out and look at it - Tracy stayed in the car. After a few minutes the
thing started alternating the colored panels on the bottom off on off etc.
/ some circulation of light / always the same amber glow. The glow looked
very "even" like the panel itself was what glowed - not as if there was a
light source from behind the panel illuminating it. AFter a minute or so
- the amber panels just stayed on - it just sat there - then like someone
gave the craft a gentle gump - it just slowly floated off over the trees.
I've seen a few other "things" but nothing ever like this.
Off soapbox - back to coding.
???
Eric
: Tom Davidson
: Brighton, CO
bob
i would hope that better suport of such claims could be made than a former
aret bell web site :)
tadchem wrote in message
<4%526.18930$3B5.5...@newsread2.prod.itd.earthlink.net>...
Mark Zenier
tadchem <tadche...@earthlink.net> wrote:
>
>Officially, the Aurora does not exist. There have been sightings of a
>black, triangular craft including one by a trained aircraft spotter who
>spotted a craft matching the description over Scotland being refueled by a
>KC-135 tanker and escorted by a brace of F-111's
>http://www.geocities.com/area51/atlantis/1545/aurora.html
An alternative for this sighting is that the folks at Area 51 are making
a FB-111 replacement. A two man stealth fighter/bomber with swing wings.
It's on the cover of Popular Science last month as the "Bird of Prey".
(Gee, our defense establishment has been taken over by Klingons). Earlier
mentions in Monitoring Times magazine talked about "The Flying Artichoke".
It apparently looks in silhouette like an spiky artichoke/thistle head
when the wings are swept forward in the high maneuverability mode.
Mark Zenier mze...@eskimo.com Washington State resident
Bill Halvorsen
> DU??
> i doubt it..
> or should i say..
> i would hope not..
> i think it would be much more likely to finmd that they used something
like
> trittium
>
About 25? years ago I had a watch with an LCD backlit by a phosphor-coated
ampoule (sp?) filled with Tritium. I loved it - and have always wondered
why they were deemed politically incorrect. The brightness did fade after
about 5 years. Still it beat the heck out of any of these EL watches that
take huge slices of life from the battery each time they are lit.
Hmmm, somewhere I think I still have the instruction manual for this watch!
bob
the easiest place to find it is either in exit signs in a hospital or movie
theator (these may be the plain old conventional battery powered.. you never
know) or in an airplane (Just about ALL exit signs in a plane are going to
have tritium)
Bill Halvorsen wrote in message ...
ae2...@wayne.edu
Uranium is what the watch contained. I don't know enough physics to be
able to refute that claim.
I can say that the batteries would last the "normal" life span you'd
expect for a watch, I don't recall having to change them more than once a
year or so. Another interesting observation was that for long periods of
time after the LCD went blank, over a week, the backlighting would reman
lit. The illumination did not appear to be at all connected to the
battery that powered the electronics.
Boy, I miss that watch.. Certainly a conversation piece, to say the least!
On Sun, 24 Dec 2000, Rich Grise wrote:
> In the way old days, watches had radium, and some suitable
> phosphor, until they decided that that was dangerous. I
> do remember that Timex with the backlight, but I have a
> tendency to guess that it was electroluminescent - the
> watch probably took a dive because the batteries would
> last about two days.
>
> Merry Solstice!
> Rich
>
> William L. Bahn wrote:
> >
> > Depleted uranium? Yeah. Right.
> >
> > Tritium perhaps.
> >
> > ae2...@wayne.edu wrote in message ...
> > >I used to have a radioactive writswatch! It was a Timex Nite-lite, made
> > >around 1980. I think they only manufactured them for one year (for
> > >obvious reasons). Had a pellet of depleted uranium in it for
> > >backlighting. I wonder how they designed the electronics to survive in
> > >such an environment?
>
>
ae2...@wayne.edu
20 miles from my home!
Interesting story, but I imagine that if it
were that easy to make "a nuclear reactor that not only generates
electricity, but also produces new fuel", that everyone would be doing it!
Andre de Guerin
>I'm surprised I hadn't heard about this kid, The incident happened about
>20 miles from my home!
>
>Interesting story, but I imagine that if it
>were that easy to make "a nuclear reactor that not only generates
>electricity, but also produces new fuel", that everyone would be doing it!
Easier and cheaper to get a pile of solar panels and rotators like the
ones used to rotate satellite dishes, then use it to generate power .
Andre de Guerin
<aic...@gdi.net> wrote:
> Radium. I have an old smoke detector I purchased for $5 due to its
>large size, and it had a sizable quantity of radium (half life of about 1260
>years) in it. That used to be the material of choice, but americium is easy
>to make and available. Am-241 is also subject to decay after a couple of
>years and becomes useless for the purpose of ionizing the air.
IIRC radium dial watches that have ceased to glow are still
radioactive, just the phosphor has been destroyed ?
> All my Am-241 sources decayed in about 6 to 9 months to the point where
>I had to replace them. You can get a standard set of Am-241 for alpha,
>thallium-204 for beta, and cobalt-60 for gamma from many places. They're
>pretty cheap.