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Author Topic: RESONANCE FREQUENCIES QUESTIONS---HELP NEEDED  (Read 16093 times)

need2know

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RESONANCE FREQUENCIES QUESTIONS---HELP NEEDED
« on: 17/10/2007 16:14:47 »

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Today at 16:24:35        

I am doing a study on the resonant frequencies of gold-au197, silver-ag107 + ag109, and copper-cu63...i am far from a scientist, and any help here would be appreciated......Studying the different periodic tables, these metals have resonant frequencies that vary from table to table..i imagine this is due to the way the testing is performed ?  these metals/frequencies are shown below.....
          {most popular}
metal         freq            freq              freq

gold           1.729mhz       -1.712mhz            -8.563mhz

silver107       4.047mhz      4.046mhz            20.233mhz

silver109      4.652mhz       4.652mhz            23.260mhz

copper#1         26.528mhz     -26.505mhz           132.525mhz

copper#2         28.417mhz    -28.394mhz           141.972 mhz

my questions are #1-  knowing these frequencies were observed in a laboratory, in a machine, in a scientific type setting, would they be the same frequencies these metals would resonate at if on or in the ground/dirt/earth ??? 
   #2- if not, exactly what frequency would these metals resonate at ?
   #3- if they do differ, is there a formula that can be worked to show the actual amount of change in these frequencies when each metal comes in contact with the earth ?

   reason for my questions is because i was told that the contact with the earth, because of the earths energy/magnatism and several other reasons would make alot of difference in the resonant frequencies..i was told that gold, when in contact with the earth would resonate at around 35-38 mhz instead of 1.729mhz...
   i would appreciate any help on this as i need to get to the exact frequency these elements resonate while in contact with mother earth.......thanks....need2know
 

Bored chemist

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« Reply #1 on: 17/10/2007 18:14:02 »
Firstly, we heard you the first time. Please don't cross post.
Secondly, what sort of resonance are you talking about?

need2know

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« Reply #2 on: 18/10/2007 12:09:03 »
sorry, didn't mean to upset anyone...i was not sure which thread to post question in so i put it in both....as to what kind of frequency, what ever kind of frequency these metals resonate ? as i said i am not a scientist..as far as i know there is only "frequency" ?   .in the periodic tables it has resonance frequencies listed...study into it shows these metals resonate at certain frequencies..the tables don't say what type of frequencies....from what i have read nearly everything on the planet resonates at its own frequency, although i have never seen anywhere that mentioned types, only differences in the resonation.......thanks,,,n2k

lyner

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« Reply #3 on: 18/10/2007 17:12:55 »
Can you give us a reference about this  'frequency' thing?
A piece of metal will resonate at any frequency you want if you cut it to the right size - either mechanical vibrations or  electromagnetic oscillations. Then there are all the various frequencies associated with atomic transitions.

Soul Surfer

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« Reply #4 on: 18/10/2007 18:25:53 »
Need2know  At first sight you are talking total rubbish.  Please can you give exact references to the texts or web pages that you are consulting to find this information and give us a bit of information about the aims of your study.

To be strictly correct frequencies mhz  are millihertz  ie thousanths of a cycle per second and make no sense in any physical terms,  MHz  is Megahertz ie millions of cycles per second.

The only frequences as low as that I am aware of that are relevant to particular atoms that are as low as this are Nuclear magnetic resonance frequencies and these depend on the strength of the magnetic field that the sample is subjected to so different experimenters could use different magnetic field strengths and get different frequencies.

However the meaning of the negative frequencies and the three values on the table does not fit with this as far as I understand so either you are ommitting a lot of essential background or you are talking some sort of new age gobbledegook.


Bored chemist

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« Reply #5 on: 18/10/2007 19:58:46 »
Is the sort of thing you mean?
http://www.chimorg.unifi.it/~chimichi/Ag.html
If so then the NMR frequencies are not greatly affected by chemical combination ( typically a few tens of ppm) but they only resonate at those frequencies in the presence of a huge magnetic field.
Why do you want to know?

lyner

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« Reply #6 on: 18/10/2007 21:59:52 »
Poor ol' need2know.
All the big guns hit him at once - bang -bang - bang!
We're really quite friendly most of the time.
Try us with something else.
btw, my watch's minute hand has a period of nearly 0.3mHz. That's pretty meaningful, S S!

Soul Surfer

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« Reply #7 on: 18/10/2007 22:02:31 »
Ah I see they are nuclear magnetic resonance frequencies.  good searching bored chemist

Quote

Note: Resonance frequencies are quoted relative to a resonance
frequency of exactly 100(2.3488 T), 200(4.6975 T), and 300(7.0463 T) MHz for 1H

The magnetic fields quoted are in tesla

Still don't see where the negative frequencies come from though



lyner

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« Reply #8 on: 18/10/2007 22:14:03 »
Could the negative and positive frequencies refer to sidebands - upper and lower about  some 'probe frequency'?

need2know

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« Reply #9 on: 19/10/2007 15:56:16 »
http://www.eclipse.net/~numare/nsinmrpt.htm

http://nmr.magnet.fsu.edu/resources/nuclei/Au.htm

http://www.nyu.edu/cgi-bin/cgiwrap/aj39/NMRmap.cgi

http://www.pascal-man.com/periodic-table/periodictable.html

http://arrhenius.rider.edu/nmr/NMR_tutor/periodic_table/nmr_pt_frameset.html

http://www.helpfulwaves.com/helpfulwaves-periodic-table.htm

to post a few different ones...might not be the exact ones posted above but there is enough for you to see the difference in the various tables....call it gobbleygook or what you wish, what i have posted came from results from testing {i guess, they might have just made it all up to get grant money, who knows ?} from  a bunch of scientist, of which i am not one.....i see that these metals resonate a frequency..i do not know how these scientists or whatever they are come up with like material resonating way different frequencies...that doesn't matter as much as the question that bugs me most...what frequency do these metals resonate while in or on the ground ??  As i know it is most likely quite different than the frequencies they resonate at while in a lab being manipulated by professors inside machines, spinning around, being subjected to magnetism, atomic blasts  or whatever it is they do to these metals to get these frequencies...bored chemist, i appreciate your insight...the magnetic thing is part of my problem...doesn't the earth a have magnetic field ? is it strong enough to make these metals resonate ? if so, how would one go about finding these frequencies ?.....there are molecular frequency generators made to generate these frequencies but from what i see in the periodic tables the frequencies these generators are resonating isn't even close to what it should be and i am trying to get to the bottom of it all....thanks....n2k

need2know

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« Reply #10 on: 19/10/2007 16:09:42 »
for any wanting info on the generator , molecular frequency generator/discriminator discussed here, including frequencies these units generate........

http://geotech.thunting.com/cgi-bin/pages/common/index.pl?page=lrl&file=/projects/mfd1/index.dat

daveshorts

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« Reply #11 on: 19/10/2007 16:30:58 »
Sorry there are a lot of people posting on the forum who have some wacky theory (which is absolutely fine), and will defend them to the death in the face of overwhelming rational arguement (which is annoying) so people can get a bit sensitive about things which look odd...

Back to the question.

Resonance just means that if you vibrate something in some way at a resonant frequency it will vibrate very strongly.

You can vibrate objects in many different ways, and depending on the way you are vibrating it or even how fast you are vibrating it whether the resonances are a property of the material, the shape of the material or a combination of the two can change.

for example the resonant frequency of a pendulum in a clock is a property of the shape of the pendulum not of the brass you made it of.

On the other hand the electromagnetic resonance in a purple object that absorbs the green light is a property of the material not its shape.

Any resonance that is going to be affected by putting it near some earth is not going to be a property of the material.

The reason that you are getting lots of different values is that you are looking at different resonances, every material will have many different resonances of differnt types

The first four you list are NMR (Nuclear Magnetic Rsonance) resonances which are radio frequency resonances caused by a property of the nuceli of the atoms interacting with a magnetic field, hence change the magnetic field you will change the resonance. So the resonant frequencies should be quoted with a magnetic field strength in tesla (T)

The last one looks wacky and not scientific at all, the home page for the site is talking about magnetising glass, and silicone, neither of which are ferromagnetic so you couldn't magnetise them.

You could in theory do NMR in the earth's magnetic field, although not with conventional equipment, the problem is that the lower the magnetic field the lower the frequency that the resonance occurs at. Normally you pick up the signal with a copper coil. The problem is that copper coils are very bad at detecting low frequency radio signals so you loose sensitivity very quickly and you can't see anything.

It is possible to use a SQUID - very sensitive magnetic field detector to do the job
http://www.lbl.gov/tt/techs/lbnl1729.html
You can then do NMR and MRI (properly Nuclear Magnetic Resonance Imaging but they lost the N as it scared people) in fields similar to that of the earth, but I think it is very slow
« Last Edit: 21/10/2007 10:29:24 by daveshorts »

need2know

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« Reply #12 on: 20/10/2007 19:32:36 »
THANK YOU VERY MUCH DAVESHORTS !!!!!!!!!!  just the type info i was hoping to get........n2k

Geotech

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« Reply #13 on: 24/10/2007 13:56:44 »
I think need2know's question revolves around treasure hunting methods. Currently, detecting buried gold or silver (coins, jewelry, nuggets, whatever) requires swinging a metal detector coil pretty much directly over the target, and even then conditions have to be right in order to detect the target (size, shape, depth, soil mineralization, sweep methods, etc).

The Holy Grail of treasure hunting is a method that will detect e.g. buried gold at long distances, say 10's to 100's of meters. One thing that has been proposed is NMR methods, which is what need2know was asking about. Some people have proposed transmitting a signal that will cause buried gold to resonate or oscillate, and somehow detecting the direction/location of resonance. So is this feasible?

Gold has an NMR frequency of 1.754MHz relative to hydrogen @ 100MHz, which establishes the test magnetic field at about 2.35T. The Earth has an average field of about 50uT, so buried gold would have an NMR frequency of about 37Hz. Someone please correct me if I'm wrong.

So would this be a feasible method? I think not, if for no other reason than 37Hz is way too low to make any kind of realistic directional receiver. But even if you could figure out a solution to the electronics, would the basic physics work? I know in magnetometry and I think MRI as well, hydrogen is the element at work. Is this because the single-proton nucleus is easy to precess? Would a solid gold structure exhibit any measurable level of NMR precession when pinged with an impulse field? Also, would a 37Hz magnetic field cause a sustained resonance?

I'd like to hear any thoughts on this approach. I am an electronics engineer with the normal physics & chemistry coursework, and I've designed metal detectors & magnetometers.

Thanks.

lyner

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« Reply #14 on: 24/10/2007 15:08:01 »
Quote
37Hz is way too low to make any kind of realistic directional receiver
Using 'nulling' techniques, you can get a much sharper peak in directivity than the nominal 'beamwidth' of an antenna. You can DF a source of only 1MHz within a  couple of degrees.

Bored chemist

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« Reply #15 on: 24/10/2007 18:54:57 »
While I realise that working out how to make a directional antenna for 37Hz would be difficult, I think the real problem is to do with sensitivity.NMR spectrometers use the strongest fields they can get. This is because the energy of the transition is small- comparable with ther thermal energy of the object so you have 2 states (with the nucleus' field aligned parallel or antiparallel with the applied field) but they have very nearly the same population. An incoming RH photon is very nearly as likely to knock an excited state nucleus down to the gorund state as it is to be absorbed by a ground state nucleus. Half the time the photon is absorbed, the other half (very nearly) it is re emited with a second identical photon. Overall the absorbtion is tiny. With a lower field strength you have even more of a problem.
I'm not saying it's impossible but it would certainly be slow; the only way you could reliably see the signal would be to average it over a long time.

Geotech

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« Reply #16 on: 25/10/2007 00:57:50 »
Using 'nulling' techniques, you can get a much sharper peak in directivity than the nominal 'beamwidth' of an antenna. You can DF a source of only 1MHz within a  couple of degrees.

True, but that's only effective when you can build an antenna whose element sizes are a substantial portion of the wavelength. 1/4-wavelength is most efficient, but you can go lower... 37Hz has a wavelength of over 8000km so it would be a huge challenge, or a huge antenna.

Geotech

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« Reply #17 on: 25/10/2007 01:16:09 »
While I realise that working out how to make a directional antenna for 37Hz would be difficult, I think the real problem is to do with sensitivity.NMR spectrometers use the strongest fields they can get. This is because the energy of the transition is small- comparable with ther thermal energy of the object so you have 2 states (with the nucleus' field aligned parallel or antiparallel with the applied field) but they have very nearly the same population. An incoming RH photon is very nearly as likely to knock an excited state nucleus down to the gorund state as it is to be absorbed by a ground state nucleus. Half the time the photon is absorbed, the other half (very nearly) it is re emited with a second identical photon. Overall the absorbtion is tiny. With a lower field strength you have even more of a problem.
I'm not saying it's impossible but it would certainly be slow; the only way you could reliably see the signal would be to average it over a long time.

In a proton-precession magnetometer we place a bottle of hydrogen-rich fluid (distilled water or kerosene, usually) inside a big coil. The coil is energized to align the proton spins, then de-energized to allow the protons to precess. It so happens that hydrogen at 50uT (Earth field) precesses at about 2kHz, so if the coil signal is amplified you can actually hear the precession decay. As I understand it, only a small minority of protons actually precess in unison, the rest are randomly hopping states as you said, and result in random noise.

Question #1: How does MRI compare? It's my understanding that the big honkin' magnetic field is always 'on', not "pinged" as in a mag. So I assume they are not looking at precession decay, but what? Precession alignment?

Question #2: Why hydrogen? Why not carbon? Are fluids easier to manipulate proton spins? Or is it the atomic weight? I.e., single proton nucleus being far easier/lower energy to align than e.g. 6-proton carbon or 79-proton gold.

Thanks.

lyner

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« Reply #18 on: 25/10/2007 11:40:57 »
MRI  involves the absorption,  of RF energy at a certain frequency in a certain level of   magnetic field.  Unlike the 'pinger' it uses pulses of rf and 'listens to' the energy given off after each pulse.  Energy at a given frequency is only  absorbed and given off by atoms in the region with the correct magnetic field.  It requires an image with some definition to it. Using a field gradient across the subject  and varying the field actually gives you a measure of the density of a  set of slices along an axis.  The steeper the gradient and the higher  the field, the greater the acuity of the image. Scanning along the two other axes and doing some sums actually locates and measures the density of H nuclei on a 3D matrix of points. It is much more expensive than a simple hand-held 'pinger' and yields much more information.
I imagine that the spin of a proton is much easier to spot when it is not bound to other nuclides in a heavier atom. Hence, they use Hydrogen.  The angular momentum of a composite nucleus  does not just involve the spin of its components.

 

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