Proton beams taste bad

wbeaty expounded in news: snipped-for-privacy@k15g2000prk.googlegr oups.com:

I remember from my youth that the "AC buzz box" welders operated around 40 VAC, though I've never took the time to measure it (I'll try to remember to do that when Spring comes to Ontario).

But if that is true, I know from experience that this is enough to give you uncomfortable shocks (with wet pavement etc.)

I was also under the impression that some old Farm lighting systems were 40 volts as well, being that it was near the limit of safe human exposure levels.

Warren

Warren wrote in news:Xns9E878475F5931WarrensBlatherings@81.169.183.62:

Isn't that why CAT scanners were invented...to increase medical profits by causing cancer and other diseases to things like livers?

Seems very reasonable when the doctor's beach house monthly payment of $9,827.26 is due the 3rd day of next month and there's a $127,826.32 balance on his trophy wife's credit card from the trips to the estate jewelry stores.

Warren wrote in news:Xns9E8785AABEA4BWarrensBlatherings@81.169.183.62:

I was a friend of the chief engineer of the local UHF ETV station before he died of old age. We were concerned Xrays might be coming out of the 7 ft tall, 4 cavity klystrons in the TV transmitter's final power amps, one visual, the other aural in the old NTSC analog system. Everyone said we were crazy until we got someone from the hospital to give us some xray film blanks we taped to our backs and set still a full shift in the engineer's operating station in front of the boiling monsters.

The visual klystron runs 18.5KV at about 4.2A if the 110VDC focusing coil around the beam through the cavities is set right. It's a great amp. Drive from the little solid state TV transmitter is around 350 milliwatts into the bottom cavity near the cathode. RF output is around 40 KW from the loop in cavity 4 after the swept-tuned broadband cavities make sure all the single sidebands get amplified about the same. The xrays come when the beam CRASHES into the huge tapered solid copper block with the beam cone drilled into it to distribute the beam's unused power more evenly in the big copper block, whos tapered exterior is machined with ribs to make it boil more distilled water before it melts. Something like 480,000 Btu pours out the steam condensor onto the back lawn, 18 hours a day, 7 days a week. (Need some heat to melt the snow in the driveway or that cold back bedroom for half a city?)

We took the exposed film back to our contact at the hospital and she ran it thru the xray developing machine. We were amazed! Because there are two xray sources spraying the inside of the building, we actually got a double image not unlike the ghosts on a UHF TV in the analog days. The visual klystron's 4.2A made a better picture than the 1.8A aural klystron's beam and you could see the difference. The focus on the picture was way out we figured because the source was so oddly shaped unlike a proper Roentgen tube target would be.

But, over 8 hours, Xray us it did! Bill sat there for 40 years so I suppose it wasn't enough to kill a human but it must have certainly weakened them. Most TV engineers I know smoke like a factory, so that's what kills most of them, not the xrays from the klystrons or HV rectifiers, which are just Xray diodes after all.

Sure is fun to play with these monster tubes....around $34K each, WITH TRADEIN, now I think. They were about $15K w/trade when one of Bill's equal-opportunity engineers, who'd been told NOT to touch the standby klystrons on the special tube swapping cart, flipped the cart over and DROPPED the tube on the floor, splitting it in two with a huge implosion bang. Both he and the tube were soon replaced. Bill shrugged it off, it wasn't his tube, after all...(c;] He kept the huge collector block as a paper weight on his desk as a warning to the rest of them....

Warren wrote in news:Xns9E8786DB726E5WarrensBlatherings@

But the output of the welder would be isolated so YOU got to choose its return path point with the "ground" electrode, which wasn't really ground.

Just touching the rods probably wouldn't shock you unless you had the return lead hooked to a solid ground, not the chassis of the rubber wheeled truck you were welding on. If you touched unpainted truck parts, that might be "exciting"!

Fred expounded in news:Xns9E878BC1D9DFCnobodyhomecom@74.209.131.13: ..

Heh heh- reminds me of a former dentist, who said "I'm close enough to retirement now to charge you an honest fee".

Warren

Fred expounded in news:Xns9E878EFCDF6B7nobodyhomecom@74.209.131.13:

..

Yikes.

I quit smoking in '87. I read somewhere that it is quite possible that the fertilizer used to grow the tobacco is the main culprit. Apparently where the fertilizer (phosporous?) is usually obtained is also where natural uranium ores are found to varying degrees. They claimed it is the radioactivity in the smoke particles when up against the lung that creates the cancer cells. This is because the radioactive elements involved (I forget now- which - not gamma) would otherwise normally be stopped by a couple of inches of air (or even a piece of paper).

It is well known that airborn uranium is dangerous to miners. The dirt and air space otherwise provides suitable protection.

I don't know enough about the science behind it to say how credible this is. But it does plausible at first blush.

How much at a hamfest? ;-)

Why- it's only someone else's money after all. ;-)

Some people are best at serving as examples of what not to be/do.

Warren

Fred expounded in news:Xns9E878FA521FC5nobodyhomecom@74.209.131.13:

Agreed generally, when things were dry. But I've had shocks just inserting the rod while standing on pavement. Probably because the ground clamp was on the car frame, which was up on steel jacks (we never had a proper hoist). Anyway, experience has made me more careful about how I insert those now (don't grip the rod too strongly, & let go as soon as possible etc.)

When we were contracting for Marine Land at the Niagara Falls (ON), we had a hand railing under construction in the animal building behind the main whale stage (lion/tiger doo really stinks, BTW). Since it was stainless steel, it was also DC welding, though just rectified.

We would leave the railing hot so that when the electrician came by (the first time), he'd check our work for smoothness with his bare hand. Given the water he was also walking through (it was always wet in there), he got a nice little surprise. He said "it's not nice to do that to an electrician!"

Since he wasn't going to be fooled the 2nd time, we filled the railing with an oxy-acetylene mix. When he came near we lit that when he wasn't looking. The associated bang would cause him to jump, and how high was the amusement of the day.

Warren

It's entirely theater. If they *didn't* provide that stuff, patients would scream about it and use circular reasoning: if it's unnecessary, why do OTHER dentists all use it?

Reality isn't determined by voting.

On the other hand, ancient dental x-rays used huge dosage, and staff needed protection from the cumulative output of thousands of x-ray photos done per year.

That depends on the actual values. If it's thousands of times less than yearly background radiation, then it's totally insignificant.

The phosphate ore (apatite rock) which is mined to make phosphate fertilizer contains certain radioactive metalws (uranium and others). Some of these break down into daughter-isotope chains which contain radon gas... and the radon then breaks down into chains which include unstable isotopes such as lead-210 and polonium-210. Particles which contain these unstable daughter isotopes can be deposited on the tobacco leaves, burned, inhaled, and deposited in the lungs as part of the tobacco tar.

Since the lungs have difficulty clearing the tar from the tissues (in part because the smoke inhibits the cilia which normally transport contaminants out of the lungs), the lung tissue ends up being irradiated when the unstable daughter isotopes break down further. The breakdown chain from radon-222 down to lead-206 (which is stable) consists of multiple steps, which emit both alpha particles (helium nuclii) and beta particles (electrons). The alpha particles seem to be the real damage-doers, as far as the lungs are concerned. The page at

The amount of radiation that a smoker receives from this source does seem to be significant (conservatively, the equivalent of a chest X-ray every day... possibly quite a lot more).

Since many of the chemicals in tobacco smoke tar have been shown to be carcinogenic, I don't think it's necessarily accurate to say that the radiation is the "main culprit", but it does look as if it could very well be a significant contributor to the elevated rate of lung cancer in smokers.

@81.169.183.62:

CAT scanners - or at least the original brain scanner - is reputed to have been invented because Godfrey Houndsfield

started getting bad headaches, and got to find out how difficult it was for clinicians to see what was going on inside the skull. Before the brain-scanner, the only techniuqe for imaging tha brain was to inject some air into the ventricles within the brain and strap the patient into a chair which could be rotated around both axes, thus moving the air bubble around inside the head. By taking X-rays of head at a varieyt of orientations you could get some idea of the shape of the brain ... but not much of an idea.

Because it produces splendid images, that look very like plates from an anatomy text-book, the medical profession fell over themselves to buy the machines.

The body scanner is a great deal less useful, and gives you a rather higher radiation dose, but produces images that are just as attractive.

Individual US doctors were ordering Body Scanners when I worked at EMI Central Research (1976-79), in the sure and certain knowledge that they could run enough patients through them to cover the interest on the several million dollars the machines cost.

-- Bill Sloman, Nijmegen

Bill Beaty expounded in news: snipped-for-privacy@8g2000prb.googlegrou ps.com: ..

I don't believe that.

It's a PITA for them to go to all this trouble. If it were safe, I could see them asking if you _want_ the lead apron. But not the routine charade.

There is still some risk, at any level.

There isn't a chromosome "slightly" or "mostly" damaged. It is either as it was supposed to be (unaltered) or it has been damaged (altered). Alter the right part(s) of it, and cancer reigns supreme.

Where the "cumulative" aspect comes into it is in general cell damage. But you're still playing cancer Russian Roulette with those critical molecules of the chromosomes.

Warren

YAWN. You're living 20+ years in the past, Larry. Most new TV TV transmitters are 100% solid state for over a decade.

on accelerator). =A0100 mA of 10 MeV protons at the working end (think abou= t it -- that's a lot of power).

am.

ng that was supposed to be in a vacumn.

Ahh I think I've seen those in Theo Gray's book "Mad Science". If I'd know about the effect when I worked at the FEL, maybe we could have made some.

Yup limitied access, but I could see the outline. Too bad you can't make the muon last a bit longer. (Say do they live longer when they are whipping around a nucleous?)

George H.

I figure at 310 K, a blackbody radiates .0524 W/cm^2, approx. 8E-23 % of which is of wavelengths shorter than 700 nm. This works out to 4.2E-26 W/cm^2 of sub-700-nm radiation.

Divide 4.26 E-26 W/cm^2 by that, and result is that one square centimeter of blackbody surface at 310 K radiates at a rate less than

I have in the past falsely seen in complete darkness the outline of parts of my body or auras around that by power of suggestion. One thing I remember from chikldhood is the demonstrator at Philadelphia's major science museum one day saying that if one gets zapped (through a handheld metal rod) by a Tesla coil, that person develops a visible-in-the-dark aura. I believed that then, and went to all hourly demonstrations of the Tesla coil that day to get myself godd-and-charged-up. The demonstrator even said during my repeat visits that I was a "repeat customer" (my words) and that I was going to have a glowing aura around myself bigtime that evening. The following evening, I did see an inch-thick fuzzy layer of dim whitish green-yellow glow around my hands and arms in a darkn room.

Then again, I also sometimes "see" "with a 3rd eye" the presences of fellow gay men through walls (in some cases seeing their movements) and inside approaching elevators. But I think that's a different item... But maybe along these lines some people can "see" people or some people in complete darkness.

US Navy says that voltages exceeding 28 or 29 volts or 29-plus-volts (I forget which) are "high voltage" and potentially hazardous. I suspect that salt water is a major factor here.

Another factor could be that 28 volts is a common voltage in aircraft - a typical voltage of a 12-cell lead-acid battery that is being charged while being most of the way charged.

Neutrons are more penetrating to some extent or another, since they are not charged particles while protons are. However, I thought that gammas had less REMs per Roentgen than alphas and betas because of being neutral and/or more penetrating. (Alphas hitting the body from outside have greatly reduced hazard due to extremely low penetration - ones emitted inside the body are *bad*.

There is also a type of nuclear bomb mentioned for producing deadly doses of neutrons outside the area subject to heat and blast damage.

The way I hear things, most cancers in persons without oncogenes (genetic aspects causing tendency to get cancer) require at least two mutations. A singly-mutated cell (or cells reproducing from such) "normally" requires at least one additional mutation to become cancerous. That is why cumulative exposure counts so much. One expected result of this is cancer rate increasing more than linearly proportionately with dose of radiation or carcinogen at least in some range of exposure. My impression is that this is often true.

Use an ammeter in series with the supply. Wet the fingers for better conductivity. Last time I did that I found I could do 300 ma easily. That was just across one hand, however.

For the 'cross chest' experiments scheduled for next week, we're planning a 2000 ma starting point. The reasoning is that there's a much wider expanse of conductive epidermal layer and therefore many more multiple paths for the test current to flow. To assure good results, we're also doing a frequency sweep from DC to 500kHz at each current step.

My lab associates seem excited by the test and seem to be preparing some sort of paperwork for me to sign. There may be 15 minutes of fame in this yet.

mike