Radioactive materials and radiation.......

[Chad L. Magee]

Per Todd Wilson's other thread on the x-ray shoe fitting machine, I have started this thread to entertain questions and inform others about radioactive devices and radiation in general.  That being said, I am not going to detail destructive uses for it (such as nukes or dirty bombs), as there are plenty of sources out there for that.  I am not an expert on radiation by any means (although I do have hands-on worker training, research experience and some classwork in radiochemistry/nuclear engineering under my belt), so if anyone else is an expert in that field, please fill in the gaps that you see (and correct me if I am wrong on something).  My goal here is to start a helpful and informative discussion on this topic (please leave the politics out of it).  Radiation can be deadly in the wrong hands, but it can serve a purpose if handled properly, such as in cancer therapy treatments....

In Todds post, the shoe x-ray machine is an example of what we have learned about radiation in the past fifty years or so.  Back when they were first put out in stores (1940s I believe), they were a novelty to help sell shoes.  Most customers did not have much experience with x-rays, so they thought it was cool to be able to see their foot bones in real time.  Soon afterward, people that worked in the stores became sick from those same machines (radiation poisioning, as the instruments have very little shielding in place).  It took until 1970 before major laws were passed to prevent them from being used.  Some were still active for years afterward (illegally, but most of the owners were ignorant to the laws and the effects from using the machines)......

Fast forward to today.  We still use radioactive sources in instruments, but have learned some valuable lessons from history that have taught care in handling/disposing of them.  Here are a few everyday items that you may use that could have radioactive materials in them (and you might not realize it):

Smoke detectors (Am isotope)
Some lighted emergency EXIT signs (tritium)
Older pocket watches (with glow in the dark painted hands - radium, I have a long story about those particular items)
Certain types of antique glass and ceramic glazes (uranium oxides)
etc........

Some examples of modern typically non-destructive uses for radiation:

Cancer treatment via either direct radiation sources or induced sources
Radioactive dyes that allow for early stage cancer detection
X-ray scans (medical, chemical, or other) that are non-destructive to the sample
XRF (x-ray fluorescence) can be used to determine the elemental composition of a fragile sample (such as an irreplaceable artifact) - NAA (neutron activation analysis) can also be used for this purpose
Meat irradiation (kills certain pathogens)
The list goes on......

My point in all of this is for everyone not to totally fear radiation (as was done in the Cold War era), but to gain some insight towards their modern uses.  One thing about handling radioactivity is this: if you don't respect it, it will give you the same......

FYI: Older aviation instruments (gauges from WWII and before) contained radium also.  Wander if any were installed on custom cars back then?.....

[Todd Wilson]

I did some reading on the shoe machine. I think it had a X-ray tube which would have put x-rays out and you could see them from a flouroscope up top. As it would react to the x-ray around your foot. I dont think there was a piece of magic rock in it that was dangerous. 

I would assume the x-ray tube was just like the tubes in old radios and or tv's  except it produced an x-ray. How this tube worked would be interesting to me. I assume the electricity of some kind was fed thru the tube as did with all tubes in radios and tv's  and the reaction of the protons and electrons inside with the gas and metals in it would produce the x-ray?! Kinda like a light bulb but an x-ray instead of light we see.

Or does all bad radiation have to come from one of the various substances from the earth like the uranium and so forth?!


Todd

[Magnumcharger]

I'm already enjoying this thread!!
Basically, (correct me if I'm wrong - as I often am) there are two forms of X rays used, natural (gamma) and man-made generated.
Gamma is that electromagnetic radiation emitted by an radio-isotope.
X-rays are generated by an a vacuum tube containing an inert gas, such as sodium hexaflouride, and uses a high voltage to accelerate electrons released by a hot cathode to a high velocity. The high velocity electrons collide with a metal target, the anode, creating the X-rays.
http://en.wikipedia.org/wiki/X_rays


In my job, I expose film to X rays thereby obtaining images of structures impossible to view by any other means.
I'm hoping that soon, I'll be working within the realm of computed radiography.
http://en.wikipedia.org/wiki/Computed_radiography

[tan top]

think there was a scare about old wrist watches  back in the 70s , as the eluminous paint on hands , numbers .. on some of them had high concentrations of radiation .... & not suitable for the young 

[squeakfinder]

think there was a scare about old wrist watches  back i the 70s , as the eluminous paint on hands , numbers .. on some of them had high concentrations of radiation .... & not suitable for the young 

The lensatic compass we used in the Army had that on the needle. There was even a radioactive symbol on it.
It was back in the 80's, so I'm wondering what type of material it was. I bought what I thought was the same type of compass from a civilian company but it would only glow in the dark if you charged it with a light, and it lacked the raioactive symbol. But it wouldn't last. I've been on land navigation courses at night, and it would be pitch black out but the Army compass was easy to see.

It was like this one...

http://www.cabelas.com/cabelas/en/templates/links/link.jsp?id=0013052511026a&type=product&cmCat=froogle&cm_ven=data_feed&cm_cat=froogle&cm_pla=0470308&cm_ite=0013052511026a

It states the one above has tritium. Don't know if thats same stuff the military used.

[tan top]

think there was a scare about old wrist watches  back i the 70s , as the eluminous paint on hands , numbers .. on some of them had high concentrations of radiation .... & not suitable for the young 

The lensatic compass we used in the Army had that on the needle. There was even a radioactive symbol on it.

thats worrying  when there is a symbol like that on it    yikes

[squeakfinder]

Had to modify that message and add to it.

[Silver R/T]

Everyone knows about how dangerous cell phones are/ear buds

[RD]

here is a question chad...

exactly how does radiation affect the cells of organic life to create a cancerous cell?  at what level does it cause the cell to mutate, and in this mutation how does it not stop the cell from being able to use mitosis to reproduce itself as we often hear that radiation can cause men to be sterile, can it not also cause a cell to not be able to reproduce itself?

[Old Moparz]

Older pocket watches (with glow in the dark painted hands - radium, I have a long story about those particular items)

Is it the one about the radium paint used years ago? I saw a documentary back in the 80's about it, "The Radium Dial Company" where the factory workers got very ill or died, & the company simply moved around the USA & started over with fresh workers.

Found it too:
http://www.roger-russell.com/jeffers/radiumdials.htm

[Chad L. Magee]

I'm already enjoying this thread!!
Basically, (correct me if I'm wrong - as I often am) there are two forms of X rays used, natural (gamma) and man-made generated.
Gamma is that electromagnetic radiation emitted by an radio-isotope.
X-rays are generated by an a vacuum tube containing an inert gas, such as sodium hexaflouride, and uses a high voltage to accelerate electrons released by a hot cathode to a high velocity. The high velocity electrons collide with a metal target, the anode, creating the X-rays.
http://en.wikipedia.org/wiki/X_rays


In my job, I expose film to X rays thereby obtaining images of structures impossible to view by any other means.
I'm hoping that soon, I'll be working within the realm of computed radiography.
http://en.wikipedia.org/wiki/Computed_radiography

Sorry for the late reply today, I've been doing some remodeling in the basement.

Yes you are correct, there are two types of x-rays as you mentioned previously Magnumcharger.  It is a bit misleading, but x-rays sometimes get called gamma rays if they are naturally produced, even though they typically do not contain enough energy to be classified as a gamma ray on the electromagnetic spectrum scale (ie. light energy).  We can only see a very small sliver of the EMS.  The sun produces wave energies that goes from one end of the scale to the other, except that we, on earth, get protected from portions due to our atmosphere.  Without that protection, we would be cooked by the high end gammas and x-rays.  In the man-produced x-ray tubes, there is a small amount of metal (Tungsten comes to mind as the primary choice, although it could be other metals) that is the source of the x-rays upon contact with free flowing electrons within the tubes.  Some of the displaced metal atoms will coat the inside of the tube over time, causing it to become "dark" with use and will eventually need to be replaced with a fresh tube.  The process for the actual X-ray creation in this case is the Bremsstrahlung (breaking radiation) effect.  

Looking back at the XRD instrument that I used at MU, it had a Mo x-ray source (not the Co one I was thinking it was, but both work in the same manner).  This is what the instrument looks like inside the thick protective cabinet:

http://www.chem.missouri.edu/x-ray/smart1k.html  

To use the instrument, you had to mount a single crystal of about 1-2mm x 0.5 mm x 0.5mm on the tip of a glass thread held in place by a steel mount that could be screwed into the instrument.  There was a good quality microscope for seeing where the crystal was on the mount.  Yes, that takes some hand-eye coordination to get it on there perfectly the first time, which needs to be done quickly with air/moisture-sensitive crystals.  (Nothing is worse than only having one good crystal and it decomposes before you can even get it into the instrument.)  The crystal is held in place by a type of grease that froze upon mounting in the instrument (cold jet of N2).  Glass was used as the holding thread because it would not interfer with the x-ray diffraction process if it happened to stick up too far during the scans.  If you did everything right (and had a good single crystal), you got some x-ray diffraction data that you could analyze after about six to ten hours of measurements.  The nice thing was that you did not have to be there the whole time....

[Chad L. Magee]

here is a question chad...

exactly how does radiation affect the cells of organic life to create a cancerous cell?  at what level does it cause the cell to mutate, and in this mutation how does it not stop the cell from being able to use mitosis to reproduce itself as we often hear that radiation can cause men to be sterile, can it not also cause a cell to not be able to reproduce itself?

What basically happens is that the DNA strands become damaged though a breakage of chemical bonds when the radiation particle hits that particular part of the molecule.  Remember, DNA is the blueprint of the organism, so it has to keep it safe.  Normally, a cell is constantly repairing DNA damage (a natural process that occurs, as even regular sunlight does cause DNA damage) and all is fine.  But, every once an a while, the DNA becomes too damaged to fix, so a key part within the cell tells it to undergo a process that leads to cell death.  The problem with that is in a cancer cell, the cell death gene gets turned off (it is usually the part that is damaged) and the cell starts to undergo mytosis again and again, replicating damaged cells, not healthy ones.  Since they don't undergo systematic death, they crowd healthy cells and rob them of their supplies.  The amount and type of radiation in a treatment is critical to whether or not the cell dies or becomes cancerous.  Too much radiation will kill even normal cells, so that is the reason why cancer treatments have to be very specific to where they target the radiation and not blast away at everything.  Certain organs are more suseptible to radiation damage than others.  Brain cells are more protected from radiation damage than skin cells because of their location....

[Mike DC]

Being exposed to radiation is basically like getting hit with small-caliber machine gun fire at the subatomic level.  It's a bunch of extremely tiny particles literally just poking holes in things as they go through. 

[Chad L. Magee]

Older pocket watches (with glow in the dark painted hands - radium, I have a long story about those particular items)

Is it the one about the radium paint used years ago? I saw a documentary back in the 80's about it, "The Radium Dial Company" where the factory workers got very ill or died, & the company simply moved around the USA & started over with fresh workers.

Found it too:
http://www.roger-russell.com/jeffers/radiumdials.htm

Yep, that is it.  The ladies that they hired to do the painting on the watchhands used to lick the fine brushes while working.  It was done to keep the brush from wadding up and to be able to paint the fine details of the watch.  Unfortunately, the radium laced paint was absorbed into their systems, leading to various problems later on....  

I used to have a radium pocket watch (circa 1910) from them that was missing the glass cover when I found it (I stored it in a lead lined box).  I ended up donating it for a display on radioactive materials at my old university.  It would ping out the second highest setting on a G-M counter when the detector head was about one inch away from the face....

The modern glow-in-the-dark watches use phosphorous paint (non-radioactive) that basically stores light energy for release later on.  A much better watch choice to have on you....

[Chad L. Magee]

Being exposed to radiation is basically like getting hit with small-caliber machine gun fire at the subatomic level.  It's a bunch of extremely tiny particles literally just poking holes in things as they go through. 

True, but not all of them will do extensive damage to all organs, as some just won't go that far into your body.  Alphas (He nucleus) does not have the punch power to penatrate like a gamma ray (or x-ray), so it can be shielded with a piece of paper.  Your skin gets the brunt of most alphas.  Betas (electron particles) can penatrate further, so more shielding is nessicary to protect yourself from them (like a piece of glass).  Gammas (and x-rays) need lead shielding for protection.  That is why the doctor puts the heavy lead beaded plates around you when you go in for an x-ray, so you don't pickup more than you need.  You also have to factor in the energy levels of the particles in determing the amount of damage that can occur, as that does effect how chemical bonds get broken in the DNA molecules....

There is one way an alpha can do internal damage within a body: by mouth.  If the radiation source is a gas (or dust) and gets breathed in, it can release the alpha inside the lungs + the daugher product would likely be radioactive also.  An example of that is Radon gas, which occurs natually from some decaying uranium isotopes.  Same could be said if a source is eaten and goes into the stomach....

[Chad L. Magee]

Squeakfinder-  Tridium is an isotope of hydrogen and is radioactive (but harmless to skin contact, not so if ingested/inhaled).  In the nucleus, it has two extra neutrons (instead of zero neutrons in a regular atom of hydrogen).  Deuterium is a hydrogen atom with one extra neutron.  The glow is coming from a phosphor that has been added that is absorbing the betas from it and then releasing them slowly as light (photons)....

[Mike DC]

   
Yeah, my machine gun analogy was really aimed at the gammas in particular.  Those are usually the movers & shakers when it comes to worries about radiation exposure concerns and humans. 

 

[RD]

how do atoms (like you stated above tridium and deuterium) which normally do not have neutrons in their nucleus, come to have the extra neutrons?  If it is not the basic atomical structure, how does the neutrons "want" or are "forced" to bind with the nucleus of that atom?

[Chad L. Magee]

how do atoms (like you stated above tridium and deuterium) which normally do not have neutrons in their nucleus, come to have the extra neutrons?  If it is not the basic atomical structure, how does the neutrons "want" or are "forced" to bind with the nucleus of that atom?

During the nuclear reaction that occurs in stars, regular hydrogen becomes converted into mostly helium during fusion.  Many other byproducts are formed during this process, among them are some of the various isotopes of the elements that we find on earth.  As certain isotopes decay or react to outward stimuli (particles like neutrons), they form different daugher products upon completion of the reaction.  One example of a potential product is tridium, which is formed from regular nitrogen-14 upon reaction with a neutron (from cosmic rays, mostly coming from the sun) to form the daughter product regular carbon-12.  In laymans terms, the neutron becomes absorbed into the nitrogen core, becomes unstable and kicks out the tritium to form another stable product. 

As to the binding of the neutrons, they are neutral particles (no charge) so they are held in place in the nucleus via nuclear force (part of another force, stong interaction, that glues quarks together to make up larger particles such as neutrons, etc.)......

[Todd Wilson]

how do atoms (like you stated above tridium and deuterium) which normally do not have neutrons in their nucleus, come to have the extra neutrons?  If it is not the basic atomical structure, how does the neutrons "want" or are "forced" to bind with the nucleus of that atom?

During the nuclear reaction that occurs in stars, regular hydrogen becomes converted into mostly helium during fusion.  Many other byproducts are formed during this process, among them are some of the various isotopes of the elements that we find on earth.  As certain isotopes decay or react to outward stimuli (particles like neutrons), they form different daugher products upon completion of the reaction.  One example of a potential product is tridium, which is formed from regular nitrogen-14 upon reaction with a neutron (from cosmic rays, mostly coming from the sun) to form the daughter product regular carbon-12.  In laymans terms, the neutron becomes absorbed into the nitrogen core, becomes unstable and kicks out the tritium to form another stable product. 

As to the binding of the neutrons, they are neutral particles (no charge) so they are held in place in the nucleus via nuclear force (part of another force, stong interaction, that glues quarks together to make up larger particles such as neutrons, etc.)......

Now is this stuff all have to occur naturally or can man get involved and zap it with some fancy machine to create the various isotope compounds?

Todd

[Chad L. Magee]

Todd-  You can make different isotopes using various machines (such as nuclear reactors, neutron beams, linear colliders, etc.).  The superheavy elements (higher than U on the periodic chart, transuranic is what they are called) are all man-made isotopes.  I attended a seminar by a lady chemist who had worked under Nobel laurate Glenn Seaborg.  She went into great detail on how it was done in their labs, probably too much detail nowdays......

On a side note, I pitched an idea to her that I had about making potentially further heavy isotopes, but she did not understand (she was in her 90s at the time and was starting to lose her hearing).....

[RD]

i have watched a thing on the science channel that was detailing the movement of photons through space.  they did an experiment where it showed the photon being at two places at the same time.  i believe they stated that this was proof that photons can travel not only as particles and waves, but also dimensionally.

what has your experience brought you to believe in regards to the movement of photons and the indescribable manner of their travel?

[Chad L. Magee]

i have watched a thing on the science channel that was detailing the movement of photons through space.  they did an experiment where it showed the photon being at two places at the same time.  i believe they stated that this was proof that photons can travel not only as particles and waves, but also dimensionally.

what has your experience brought you to believe in regards to the movement of photons and the indescribable manner of their travel?

I will admit that I am a bit rusty on my quantum theory, as my last class in them was years ago, so take my following answer with a bit of salt as it may be incorrect.   I am going off the top of my head at the moment here.  My recollection of quantum physics/chemistry allows for the particle/wave duality to coexist in certain terms for photons. The question on coexistance with different dimensions at the same time is a good one, as there are many dimensions that we just can not directly physically measure, so we lose a real mental picture of what their existance means/is.  [A lot of students that I have taught chemistry to had a very hard time picturing a simple 3-D molecule in their head by looking at the chemical structure (2-D) drawn on a piece of paper.  They could not even grasp that time was another dimension, so not everyone can do this easily.]  Sure, it is not too hard to visualize the existance of the fourth dimention (time) if you really try to, but what about higher levels.  I can rationalize their existance by putting it in terms of rotational (operational) vectors upon a lattice, as the X, Y, Z planes are the 3-D world that we are familar with.  The class on x-ray crystallography helped me in visualizing lattice layouts and the linear operators needed to translate though a structure into multilayers, all done in my head before I try to work on the data using the computer program.  Yes, that can sometimes lead to nightmares, such as a never ending rubics cube equation (various structure positions) in multiple dimentions.... 

There was a NOVA program a few years ago that had a couple of researchers who had sent a photon literally back in time (only by a fraction of a millisecond though) though a process of tunneling though a material.  Tunneling is a process where by a particle can pass though an immovable object instantanously as it contacts the walls of the object.  The photon in this case was a laser beam from a CD player that transmitted the song though a material that would normally prevent the beam from reaching the speaker on the other side of the block.  So, at one point in time, the same photon was in two places in our world.  I was a bit sceptical about it, but in a way, it does prove that the photon is moving also in the fourth dimension at the same time it moves in the rest of them.  [Since then, I have not heard a rebuttal about the research being a fraud, so that gives it some merit, as some scientists like to poke holes in faulty work, especially if it has been in the media.]  The route that it takes in the fourth dimension might overlap into a different position in the 3-D world, leading to the situation that was observed.  This does not prove that human time travel is possible, as a photon and a human are vastly different things......

[71bigblock]

Huh?   

[Todd Wilson]

So what are these dudes smoking?

http://www.newscientist.com/article/mg20126911.300-our-world-may-be-a-giant-hologram.html


Todd