In , George Herold wrote (I edited for space and line count):
Any possibilities of practical long life of muons if they are whipping around heavy nuclei? What if the muons are multiple, maybe same number as number of electrons in elements with only complete electron shells or ones with higher ionization potential?
For example: Put 10 muons around a thorium (atomic number 90) nucleus, so that they form a miniaturized arrangement of the electrons in a neon atom. That nucleus-with-muons would take on 80 electrons, and chemically, electrically and spectrally this would be mercury. But with 1.16 times as much atomic mass as mercury, its vapor would have only about 92.5% of the heat conductivity of that of normal mercury vapor.
This would slightly reduce the heat conduction loss in high pressure mercury vapor lamps, metal halide lamps, and high pressure sodium vapor lamps. HPS lamps have mercury added to adjust electrical characteristics and to decrease the heat conductivity of the metal vapor.
Furthermore, reduced heat conduction means a slightly higher arc temperature is permissible - with great increase of radiation output and power input per unit area of arc, and greatly decreased percentage of input power becoming heat conduction loss. Furthermre, most MH and especially HPS lamps' arcs produce a fair amount of IR and comparatively little UV, so an arc temperature increase would increase the percentage of radiation from the arc that is visible light.
How about a more extreme example? Put 36 muons in orbit around a thorium nucleus, to get a muon shell structure like the electron shell structure of krypton. The nucleus-plus-muons would then take on 54 electrons, to make an atom that is chemically, electrically and spectrally a xenon atom. But with twice the atomic mass, for 71% as much heat conductivity (inverse square root) as that of normal xenon. The benefits for xenon arc lamps and flashlamps should be obvious should this be doable.
How about a nickel nucleus (atomic number 28) with 18 muons around it for a muon shell structure like the electron shell structure of argon, and 10 electrons to be effectively neon with 2.9 times the usual atomic mass and 59% of the usual heat conductivity of neon?
If you're terrified of radiation, be aware that a major portion of our yearly dose comes from our own bones. Start thinking about this constantly! Be afraid! Sleeping next to someone will increase your yearly dose by a percent or so, to say nothing of laying on top. Insist on separate beds! If you're terrified of radiation, don't EVER EVER EVER fly in a plane. Bring a tiny GM counter on board and you'll see. It doesn't click, it roars. IIRC it's 0.5mRem/hour. Much higher during flares. A trip across country equals a couple chest-xrays worth of radiation. An article about this mentions that airline pilots commonly get cataracts earlier than other populations. Radiation cataracts.
But if you're not terrified, then ignore the emotional rhetoric and instead dig up some numbers. A 1 mRem dental x-ray increases your existing yearly radiation dose by 0.3%, and increases your lifetime cancer risk by .00004% worst case. In other words, if you receive ten thousand dental x-ray doses, your lifetime cancer risk basically doesn't change much (only a 0.4% increase.) A few hundred dental x- rays is nothing. A few thousand of them is nothing. But it's wise to avoid getting 100K or a million of them in your lifetime.
So as far as dental x-ray fear is concerned, typical fears of the public are off by about 10,000 (or, dental x-rays are about 10K times safer than people think they are.)
When Israel opened up in the 50s, all immigrants from N. Africa were given 100R xray dose to the scalp. 100,000 mRem. This cures tinea capitis fungal infection by triggering massive hair loss. Didn't this kill millions? In recent followup testing they found that this population had a couple percent increase in brain tumors: benign meningiomas. A hundred rads of x-rays?! The LD50 for full body dose is only 500R! But then our heads are less sensitive, cancer-wise, and limbs/hands even less.
The big X-ray fears back before the 1930s were from famous cases of extremely malignant cancer. SKIN cancer, received by xray techs from constantly repeated 'sunburns' working under unshielded hospital sources. Sticking hands in a "shoe store x-ray" is very similar to acquiring radiation burns and increased cancer risk from playing outdoors in summer sunlight. The people who should worry are the people who get far more than this (e.g. shoe store clerks sitting next to the x-ray machine all day.)
At dentists' offices, when they bring out the lead apron, I say "that's fake, you know. Irrational fear." Usually they laugh and put it back away again. My current dentist doesn't even bother. The dental people seem familiar with the actual hazard stats. I think dentists are afraid of cigarettes giving someone throat cancer, then starting a lawsuit because the dentist didn't provide a lead-filled throat shield. Scary. RA-DEE-ATION BOOGA BOOGA! To cure irrational fears, calibrate against common risks from sports, climbing ladders, or being overweight. A single 1mRem x-ray exposure is insignificant: it's like driving 4mi in a car. Now being 15% overweight ...THAT should terrify us all.
Suppose you reduce a particular risk by 10^3 times. That's "Still Some Risk." OK, take actions that reduce it by 10^30 times. "Still Some Risk." No matter how mindboggingly safe something becomes, "that's still some risk." The phrase is not rational, since it acts to obscure the difference between significant risk, versus a non-zero risk.
It's a matter of SNR. If a particular cancer risk is totally buried in the "noise" of known cancer incidence, then it's an insignificant risk. The risk becomes significant if it can increase or decrease the existing risk significantly. Should we all fear a microsecond exposure to sunlight? It might cause cancer!!! No it won't. We already have a ~20% chance of death by cancer, and such brief UV exposure won't change that value. Now many thousands of hours of Florida sunlight, then you're talking possible risk. But not millisecond exposure, or ten, or a full THOUSAND mSEC OF DAAAANGEROUS SUNLIGHT. There's no signal there, only noise.
So the real issue is, what is our lifetime cancer risk, and what events will change it? For just radiation, yearly avg dose is
360mRem (partly coming from potassium in our bones.) The risk of death is about the same as that for a vacation extended cross-country car trip, one per year.
Of course there is. There's immediately repaired damage, slowly repaired damage, and permanent damage. For example, people born with a defect in the major DNA-repair molecule must avoid letting sunlight touch their skin, and they typically won't survive to adulthood. But if a healthy person starts acting as if their cancer risk is the same as one of these "Moon Children," that's just silly.
No you're not, not if the damage rates are enormously lower than the damage rates that normally produce cancer. Such crazy thinking would lead you to stay indoors, since going outside is dangerously "playing russian roulette" with clear-weather lightning strikes, getting hit by plane crashes, and death by meteors. Obviously people who fear such things, or even seriously consider them, are not quite sane. The same goes for radiation risk: rational people treat 100K lifetime dental x- rays as a borderline hazard. Crazy people think that a few x-ray doses per year is something to worry about. They're off by 10K times.
This is news to me. It appears to me to show relativistic effects being claimed and having measurements highly agreeing with 4 calculations for both lead and tin-substituted-for-lead in voltage of "lead-acid type" batteries.
This reminds me of how deuterium oxide is toxic to humans if consumed to extent making human water content having its hydrogen having more than a percent or whatever being deuterium.
This also reminds me that the various isotopes of mercury have their
253.7 nm emissions differing by a sufficient number of parts per million to reduce self-absorption related losses in fluorescent and germicidal lamps in comparison to single-isotope mercury. (This is not an issue with high pressure mercury vapor lamps, where this spectral emission feature is broadened to nanometers and the other main ones are either or both of being broadened or having the mercury vapor being "optically thin".)
This also reminds me of deuterium lamps. However, use of deuterium as opposed to protium in those appears to me to be from increased molecular mass reducing "elastic collision loss" (similar to heat conduction) favoring less loss and accordingly favoring a more favorable-for-purpose average kinetic energy of free electrons.
This does mean that greatly heavier versions of mercury, xenon, neon or anything else could easily differ significantly from the "usual versions" in low pressure discharge lamps. Reduction of "elastic collision loss" (perhaps from use of heavier versions of gas atoms) in a low pressure discharge lamp tends to reduce average kinetic energy of free electrons, resulting in a change in electrical and spectral properties of the lamp in question.
However, it strongly appears to me that in "high pressure" discharge lamps, AKA "high intensity discharge" / HID lamps, the elastic collision loss separable from "more-true heat conduction" is usually insignificant, and a major change in atomic mass changes atomic energy levels by only parts per million, and changes whatever (when there are any) molecular energy levels by "in temperature terms" fraction of a degree K to at most
10's of degrees K out of typically 4,000's to around 6,000 K arc temperature.
There is the "sidetrack matter" of discharge lamps being considered of "high pressure type" even when the absolute pressure in question is up to an order of magnitude below atmospheric pressure. High pressure sodium vapor lamps mostly have combined "starting" fill gas, mercury vapor, and sodium vapor partial pressures totalling less than atmospheric pressure. There are also "medium pressure" mercury vapor lamps, which strongly appear to me to be a minor variant of "high pressure" ones, as opposed to "low pressure" or "in-between", in how they work electrically, thermally and spectrally.
Although this is true and apatite can contain a bit more uranium than most things it is often forgotten that uranium is a relatively common element with an average crustal abundance of 2ppm in many soils and rocks. That is more common than tungsten or molybdenum. What is *rare* is to find decent uranium ore that is worth the effort of mining it.
In the good old days we used to demonstrate our fast ultra trace capabilities to VIPs by measuring trace elements in tapwater. That was until the water company complained. It was trivial to detect most of the actinides in water when you have sub ppt level sensitivity.
Quite likely it is at least a factor, but the evil black tarry mix of known carcinogens stuck in the lungs is also pretty damaging.
I can vouch from practical experience as an astronomer that in a truly dark photographic darkroom you never see anything at all apart from noise inside the eye with the lights out. Many darkrooms have light leaks on the doors which become visible after a while, but those with a folded light trap entrance are truly dark. Same with caving once you are deep inside a cave.
The eyes sensitivity and noise floor goes up considerably in the first fifteen minutes of total darkness and you do see random speckles but nothing that is related to other people. In fact you have to be careful not to walk into them. The fixed objects in the workspace are easy you quickly learn where they are. By comparison outside at night is relatively bright from the sky glow and you can see to some extent by starlight on a clear night.
Not checked your numbers. I have a hunch that some women can see a little bit further into the near IR than most men based on how they perceive the Orion Nebula. Most people if they see colour at all see apple green OIII, but the odd woman has seen a dark red which could be SII at 672nm. I can see that wavelength but not with much sensitivity.
I bet it could become an "emitter" as well as a "sensor!"
Wow, look at the cleaned up airbrush version of the above photo:
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Now if this below is a cleaned-up version of a long-exposure TC photograph...
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And this below is also an edited photograph...
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then what the frack was that beam generator device behind little Nickkie? A fanciful artist conception? Or yet another lost Tesla device? How about letting a Tesla Coil streamer follow a beam of x- rays rather than following a UV laser. Conveniently locate your high- vac Geissler tube on top of an oil-insulated TC. (Remember old headline re. 'Tesla shadowgraph x-ray through human chest at distance of 40 yards.') Perhaps the above GIF is actually a heavily airbrushed photo of Tesla's collimated 40-yard x-ray emitter. He keeps it secret, yet subtly "discloses" its existence by publishing photos of it. But not quite photos, so we'll all assume that the magazine artist was just making stuff up, rather than illustrating a real device. (Get inside Tesla's head and you find twisted paranoid sneakiness, as expected.)
Lead apron is because gonads are ultra-sensitive. Brick wall is because each patient gets one once a year or so, x-ray tech does it several times a day, every day of the week.
A few months ago I went to a dermatologist about a wart, which turned out to not be a wart at all, but keratosis or some such; the dermatologist (who was a hot young babe) was looking over my skin, and asked if I use sunscreen. I've never used sunscreen in my life! But, to assuage her fears, I told her I wear a hat.
She had a can of freeze spray on my desk, and I had to ask her to use it on my un-wart; she said it was unnecessary, because the thing was totally benign, but I wanted it gone because it was ugly. It didn't hurt a bit, the thing scabbed up and fell off in a few days, and now the spot is smooth as silk. :-)
It must not be too dangerous - a couple of years ago, I had a CAT scan of my belly, because of pancreatitis. There was a live real-time display on the wall that I could see - the med. techs were having some kind of conference, and they left the thing on - it was kinda kewl watching the display while I rolled my stomach and stuff.
Surgeon calls plumber. Plumber fixes toilet or whatever, and presents his bill. Surgeon says, "Holy crap! I don't get this much for _surgery_!" Plumber says, "Neither did I, when I was a surgeon. ;-)"
"Amazing pictures of "glittering" human bodies have been released by Japanese scientists who have captured the first ever images of human "bioluminescence".
Although it has been known for many years that all living creatures produce a small amount of light as a result of chemical reactions within their cells, this is the first time light produced by humans has been captured on camera.
Writing in the online journal PLoS ONE, the researchers describe how they imaged volunteers' upper bodies using ultra-sensitive cameras over a period of several days. Their results show that the amount of light emitted follows a 24-hour cycle, at its highest in late afternoon and lowest late at night, and that the brightest light is emitted from the cheeks, forehead and neck.
Strangely, the areas that produced the brightest light did not correspond with the brightest areas on thermal images of the volunteers' bodies.
The light is a thousand times weaker than the human eye can perceive. At such a low level, it is unlikely to serve any evolutionary purpose in humans ? though when emitted more strongly by animals such as fireflies, glow-worms and deep-sea fish, it can be used to attract mates and for illumination.
Bioluminescence is a side-effect of metabolic reactions within all creatures, the result of highly reactive free radicals produced through cell respiration interacting with free-floating lipids and proteins. The "excited" molecules that result can react with chemicals called fluorophores to emit photons.
Human bioluminescence has been suspected for years, but until now the cameras required to detect such dim light sources took over an hour to capture a single image and so were unable to measure the constantly fluctuating light from living creatures.
While the practical applications of the discovery are hard to imagine, one can't help wondering what further surprises the human body has in store for us." ______
I'm a bit dubious about the "thousand times weaker than the human eye can perceive" because Human eyesight is quite sensitive
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"In their experiment they allowed human subjects to have 30 minutes to get used to the dark. They positioned a controlled light source 20 degrees to the left of the point on which the subject's eyes were fixed, so that the light would fall on the region of the retina with the highest concentration of rods. The light source was a disk that subtended an angle of 10 minutes of arc and emitted a faint flash of 1 millisecond to avoid too much spatial or temporal spreading of the light. The wavelength used was about 510 nm (green light). The subjects were asked to respond "yes" or "no" to say whether or not they thought they had seen a flash. The light was gradually reduced in intensity until the subjects could only guess the answer.
They found that about 90 photons had to enter the eye for a 60% success rate in responding.
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Dirk
http://www.neopax.com/technomage/ - My new book - Magick and Technology
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