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Handy andy

ionization of gases

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It mentions CERN used this to contain antiprotons, I thought these were just theoretical, should that have read positrons, or have CERN managed to create an antiproton.

 

Antiprotons are created since 1955, as you can see on wikipedia:

https://en.wikipedia.org/wiki/Antiproton

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You didn't answer my question in post#21?

 

"Your interposing cloud of electrons would appear to me to constitute a plane rather than a pulse?" ... not a pulse

 

Maybe I'm fixated on an issue already closed.

Edited by EdEarl

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"Your interposing cloud of electrons would appear to me to constitute a plane rather than a pulse?" ... not a pulse

 

Maybe I'm fixated on an issue already closed.

 

Sorry Ed I didn't think your question was directed at me. My post 25 outlines what I am thinking about, on your post you are talking about potentials and connecting terminals to ground. The ground connection is a definite no no, when trying to collect the charges onto separate conductors, they will be neutralised by the earth connection. The positive charges will attract electrons out of the conductor leaving it with a positive charge, that can be used. If it is grounded the +ve charge would be wasted. The conductors collecting the charges need to be floating electrically. To measure the voltages (accumulated charge) on the conductors none grounded test equipment should be used, and rubber boots, and a lot of caution, the voltage could float to a dangerous voltage.

 

A cloud of ions should accumulate due to successive pulses preferably impulses, delivered at very high voltage, in the vicinity of the voltage pulse source. The voltage pulse will tend to drive the electrons away from it, but the positive charges should stay closer. The general idea is magnetic fields would be the best to separate the charges.

 

The reason I am particularly looking at impulse rather than DC, is that a very short wavelength ie very fast rising edge could emulate an x-ray or even gamma rays( in my dreams). The rising edge of the pulse will carry more energy than the DC part of a pulse. A square wave if represented using fourier transforms can be constructed from a range of frequencies.

 

The concept I had using hot gases has already been done, so that idea is closed.

 

Apologies for not answering but the thread is not intended to be about an arguable definition of a term. It is about ionisation (possibly as a result of a avalanche), separation of oppositely charged ions and collection of ions.

Edited by Handy andy

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The math huh

 

http://mathworld.wolfram.com/DeltaFunction.html

 

There are some pretty pictures of a sine expansion, amongst others.

 

But see also my response to Strange below.

 

I particularly liked your last sentence, emboldened, especially the bit about pulsed DC, which is what I was talking about and Handy would be generating.

 

What exactly is the non zero portion of a perfect pulse if not DC?

 

It is a stright line parallel to the horizontal axis.

 

Because of this when designing say pulse transformers or transmission lines etc it is common to break the puls into three sections.

 

Section 1 The rising front is analysed by high frequency equations since it has many high frequency components,

 

Section2 The flat top is analysed by DC or low frequency analysis since it ideally has zero freqency components

 

Section 3 The trailing edge is analysed by HF analysis as the leading edge.

 

An additional pulse characteristic called droop is introduced in real world analysis of section 2.

 

This sort of situation appears in radar systems, and in analog power supplies where enormous current pulses occur for very short durations during the reservoir charging/discharge cycle.

 

 

 

 

 

See here particularly the quote underlined.

 

http://www.thefouriertransform.com/pairs/impulse.php

 

 

Frequency = 1/wavelength yes?

 

So what is the frequency of a zero length pulse?

 

So I am saying that both terms are inappropriate for some repetitive and non repetitive 'generalised' functions.

 

We see these in solitons, heaviside impulse functions and dirac functions amongst others.

 

Hi do you happen to have a pdf or a web link with an example of steps 1, 2 and 3 above. Ref the maths huh link, very neat, it takes me back to my youth, and was surprisingly simple to follow. It will help me to have an example to get up to speed again.

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Hi do you happen to have a pdf or a web link with an example of steps 1, 2 and 3 above. Ref the maths huh link, very neat, it takes me back to my youth, and was surprisingly simple to follow. It will help me to have an example to get up to speed again.

 

 

Very quickly (there could be more, I have a good deal spread about.) is this the sort of thing you are looking for?

 

 

https://books.google.co.uk/books?id=DSHSqWQXm3oC&pg=PA936&lpg=PA936&dq=pulse+terminology&source=bl&ots=o0QQEMJH9R&sig=QPagCDwrh4-bV2zeC5SGczqngf0&hl=en&sa=X&ved=0ahUKEwjunfbq7svTAhWpLsAKHfLCChM4ChDoAQgUMAA#v=onepage&q=pulse%20terminology&f=false

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Its interesting, but not really what I am looking for. My problem is more of a transmission line problem, using very fast rising edges, with reflected pulses causing standing voltages on the cable. I was originally thinking about the Tesla Bifilar pancake coil circuit, and pulsing it very high frequency.

 

I know I can ionize the air using high voltage dc, but think it must be more efficient with a very fast pulse train, which will have some very short wavelength components making up the pulses. This may work more like radiation than bog standard dc. (did you notice the way I avoided writing high frequency DC pulses)

 

The magnetohydrodynamic generator method demonstrates I am thinking in the right direction and can separate the ions using magnetic fields. The Townsend discharge shows I can get an avalanche effect via passing a small current. What I want to do is create an avalanche production of ions around my voltage pulses in the surrounding air, without passing a current. Pulsing a seeded vacuum will make the vacuum ionize easier and stay ionized longer, hopefully long enough to collect the positive and negative charges. Hopefully you can see what I am aiming at doing.

 

Thank you very much for the response, it is appreciated.

Edited by Handy andy

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(did you notice the way I avoided writing high frequency DC pulses)

 

Not only did I spot it, I liked the way you avoided juxtaposition of self contradictory terms.

 

However this one baffles me

 

 

the vacuum ionize easier

 

Ionise a vacuum?

 

 

Hopefully you can see what I am aiming at doing.

 

My latest guess is that you want to construct a source of ionized air for test purposes in your goal of recovering energy from already ionised air.

 

I don't know where you are or what your resources are but these guys are really friendly and swop useful kit a lot.

 

http://www.vintage-radio.net/forum/index.php

Edited by studiot

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Not only did I spot it, I liked the way you avoided juxtaposition of self contradictory terms.

 

However this one baffles me

 

 

Ionise a vacuum?

 

 

My latest guess is that you want to construct a source of ionized air for test purposes in your goal of recovering energy from already ionised air.

 

I don't know where you are or what your resources are but these guys are really friendly and swop useful kit a lot.

 

http://www.vintage-radio.net/forum/index.php

 

Er yes my grammar is getting worse the older I get.

 

Yes I want to initiate an ionization process which will be easier in a vacuum. Do you happen to know which gases would be best for this purpose.

 

Thank you for the link I will check it out.

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You might like to seek out this book

 

Electron Physics and Technology

by

Thomson and Callick (note not JJ Thompson with a p)

 

English Universities Press

 

(So sad they were shut down)

 

Chaper 5 Gaseous conduction is of particular interest.

But the whole book is a mine uf useful theoretical and practical information from materials, to pumps to vacuum generators to HV pulse generators.

 

Also very relevant is

 

Advances in High Voltage Insulation and Arc Interruption

by

Maller and Naidu

 

Pergammon

Edited by studiot

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You might like to seek out this book

 

Electron Physics and Technology

by

Thomson and Callick (note not JJ Thompson with a p)

 

English Universities Press

 

(So sad they were shut down)

 

Chaper 5 Gaseous conduction is of particular interest.

But the whole book is a mine uf useful theoretical and practical information from materials, to pumps to vacuum generators to HV pulse generators.

 

Also very relevant is

 

Advances in High Voltage Insulation and Arc Interruption

by

Maller and Naidu

 

Pergammon

 

Excellent, thank you for the references, I am temporarily back in the UK for a month or so, and there are some University book shops only 20 miles away with actual text books written in English, I will see what they have, failing that I will get them of the internet.

 

Many Thanks

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Excellent, thank you for the references, I am temporarily back in the UK for a month or so, and there are some University book shops only 20 miles away with actual text books written in English, I will see what they have, failing that I will get them of the internet.

 

Many Thanks

 

 

Happy book hunting, but be aware that these are older books, (mid 20th century), commensurate with your area of interest and techniques you might have available to you as an amateur.

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What I want to do is create an avalanche production of ions around my voltage pulses in the surrounding air, without passing a current. Pulsing a seeded vacuum will make the vacuum ionize easier and stay ionized longer, hopefully long enough to collect the positive and negative charges. Hopefully you can see what I am aiming at doing.

When you create ions in air, you will have current flow; though, it can be very small.

 

What is a seeded vacuum? On Earth, a gas between cathode and anode will remain ionized as long as a voltage is applied to the cathode and anode. There are too many electrons in the environment for an ion to remain ionized for very long without a potential difference (voltage) to keep it ionized; although, it is possible to capture charge in a capacitor. If your purpose is to collect a charge, both a Van de Graaff and Wimshurst collect charges of static electricity.

 

It is not possible to create ions in a vacuum, because an ion is an atom stripped of an electron. A vacuum tube applies a voltage between a hot cathode (-) and an anode (+), which cause electrons to travel from cathode to anode causing a current. Since no vacuum is perfect, there will be a few atoms in any vacuum.

Edited by EdEarl

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Happy book hunting, but be aware that these are older books, (mid 20th century), commensurate with your area of interest and techniques you might have available to you as an amateur.

 

You wont believe this but I used to be a pro :) I have just forgotten a lot more than I know now. :(

When you create ions in air, you will have current flow; though, it can be very small.

 

What is a seeded vacuum? On Earth, a gas between cathode and anode will remain ionized as long as a voltage is applied to the cathode and anode. There are too many electrons in the environment for an ion to remain ionized for very long without a potential difference (voltage) to keep it ionized; although, it is possible to capture charge in a capacitor. If your purpose is to collect a charge, both a Van de Graaff and Wimshurst collect charges of static electricity.

 

It is not possible to create ions in a vacuum, because an ion is an atom stripped of an electron. A vacuum tube applies a voltage between a hot cathode (-) and an anode (+), which cause electrons to travel from cathode to anode causing a current. Since no vacuum is perfect, there will be a few atoms in any vacuum.

 

What I am proposing to create is a momentary very high DC impulse voltage, with reference to ground, lots of times a second, to continually shock the air around the voltage source. I do not propose to make it arc to ground as in a lightning strike. The ionization process can result in an avalanche production of anions and cations, which do not immediately recombine. By seeding the air with a a particle that is easily ionized the avalanche process will be initiated with less energy.

 

This will ionize the air, and by repeatedly shocking it will drive the electrons away from the voltage source, due to the fact they have a lower inertia than the nucleus of the atoms they are released from.

 

When I stated vacuum I did not mean a perfect vacuum, I meant at reduced atmospheric pressure, so that the likely hood of recombination is reduced, as in the ionosphere. We see sprites in the atmosphere above thunderclouds, positrons and electrons are blasted out into space from very large thunderclouds they do not immediately combine as they might in an ideal gas. I am particularly interested in the transient states of the ions, and the possibility of separating them using a magnetic field, to usefully use their charges. This separation is done successfully via magnetohydrodynamic generators as has pointed out above. Modulating a magnetic field through the ionized air will have the effect of separating the charges.

 

The Van de Graaf only collects one polarity of ions, I want to collect both anions and cations from the atmosphere. I am not familiar with the Wimshurst but will take a look.

 

As an aside (speculation thread possibly) lightning balls can exist at almost ground level and pass through walls, they do not immediately recombine, and consist of ionized particles, produced by lightning or plasma. I have no difficulty believing that hot electrons can pass through a wall but I do find it difficult to believe that molecules of gas can pass through a wall. It has now been proven that positrons are produced in thunderclouds on mass. It may actually be the case that lightning balls are a mixture of both positrons and electrons. Even more speculative, lightning balls have been observed to be much larger dimensions at higher altitude, ie visible to the naked eye a mile high etc. It is not impossible that the Tunguska explosion was a monster lightning ball, which exploded 5 miles up. The reason I state this is there is no crater, where a meteor struck. The object which was observed by eye witnesses was moving slowly. Huge high altitude lightning shows illuminated northern Europe for a week before the event. It is not impossible that a lightning ball was driven down from the upper atmosphere, and compressed as it descended, driving electrons and positrons into each other, releasing a lot of energy. It is also possible that the disaster at mecca was another explosion emanating from the very large thundercloud that was passing by, on a lot smaller scale than Tunguska, but killing a lot more people.

 

Thanks for the replies.

Edited by Handy andy

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You might like to seek out this book

 

Electron Physics and Technology

by

Thomson and Callick (note not JJ Thompson with a p)

 

English Universities Press

 

(So sad they were shut down)

 

Chaper 5 Gaseous conduction is of particular interest.

But the whole book is a mine uf useful theoretical and practical information from materials, to pumps to vacuum generators to HV pulse generators.

 

Also very relevant is

 

Advances in High Voltage Insulation and Arc Interruption

by

Maller and Naidu

 

Pergammon

 

Received the books this morning, the electron physics book looks very interesting, its a bit if a refresher course or a trip down memory lane.

 

Thanks again for the recommendations. They should keep me quiet for a few days.

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The Van de Graaf only collects one polarity of ions, I want to collect both anions and cations from the atmosphere. I am not familiar with the Wimshurst but will take a look.

 

In Van de Graaff generator, on bigger metallic sphere there is positive charge, because the electrons are torn out of it, and they are moved to smaller metallic sphere, usually on stick, with wire connected to transport belt. Smaller metallic sphere will have negative charge, because of abundance of electrons on it.

When you place small sphere say 10 cm away from bigger sphere, it's like one huge capacitor, with air acting as isolator.

But only to the moment in which voltage between electrodes-spheres is too high and discharge will reunify electrons on bigger (positive) sphere.

In example it'll be approximately 300 kV.

Presence of ions in the air, will just speed up discharge of Van de Graaff generator.

f.e. if you would place there radioactive isotope which will be decaying and newly created particles would ionize air medium, discharge would happen faster than without radioactive isotope.

That's how Geiger counter/radioactive meters are working.

Edited by Sensei

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In Van de Graaff generator, on bigger metallic sphere there is positive charge, b..

Smaller metallic sphere will have negative charge, because of abundance of electrons on it.

 

 

When you place small sphere say 10 cm away from bigger sphere, it's like one huge capacitor, with air acting as isolator.

 

Size is not important ( to polarity)

 

It doe sinfluence capacitance directly

csph8.gif

(from http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capsph.html)

So with a relatively large sphere a metre in diameter the capacitance is a tenth of a nano farad.

That's not a huge capacitance. It's of the order of the capacitance of a metre or so of teh cable used to connect the TV Ariel to the receiver.

Or ten billion times less than one of these

http://uk.rs-online.com/web/p/products/1094089/?grossPrice=Y&cm_mmc=UK-PLA-_-google-_-PLA_UK_EN_Passive_Components-_-Capacitors&mkwid=spGjDHJxF_dc|pcrid|88057073523|pkw||pmt||prd|1094089&gclid=CjwKEAjwxurIBRDnt7P7rODiq0USJADwjt5DsrXNeDRpKWl4Hp_9F8B1Wdn3flgG0m-1z0mgKscp_BoCiQzw_wcB

 

The Van de Graaf only collects one polarity of ions, I want to collect both anions and cations from the atmosphere. I am not familiar with the Wimshurst but will take a look.

 

Get two V de G generators - one of each polarity.

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In Van de Graaff generator, on bigger metallic sphere there is positive charge, because the electrons are torn out of it, and they are moved to smaller metallic sphere, usually on stick, with wire connected to transport belt. Smaller metallic sphere will have negative charge, because of abundance of electrons on it.

When you place small sphere say 10 cm away from bigger sphere, it's like one huge capacitor, with air acting as isolator.

But only to the moment in which voltage between electrodes-spheres is too high and discharge will reunify electrons on bigger (positive) sphere.

In example it'll be approximately 300 kV.

Presence of ions in the air, will just speed up discharge of Van de Graaff generator.

f.e. if you would place there radioactive isotope which will be decaying and newly created particles would ionize air medium, discharge would happen faster than without radioactive isotope.

That's how Geiger counter/radioactive meters are working.

 

Thanks again for the links, they are very interesting but not exactly what I am aiming at doing. The Wilmhurst device is interesting to look at at https://en.wikipedia.org/wiki/Wimshurst_machine.

 

I am interested in generating multiple EM pulses to drive off any free electrons, leaving a net +ve charge behind around the EM pulse source, the ionized positive ions will collide with other other atoms and ionize them also. Repeated EM pulses will drive of more free electrons. I am considering separating any positive or negative ions with via a switched magnetic field, to guide the charges onto collection plates.

Size is not important ( to polarity)

 

It doe sinfluence capacitance directly

csph8.gif

(from http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capsph.html)

So with a relatively large sphere a metre in diameter the capacitance is a tenth of a nano farad.

That's not a huge capacitance. It's of the order of the capacitance of a metre or so of teh cable used to connect the TV Ariel to the receiver.

Or ten billion times less than one of these

http://uk.rs-online.com/web/p/products/1094089/?grossPrice=Y&cm_mmc=UK-PLA-_-google-_-PLA_UK_EN_Passive_Components-_-Capacitors&mkwid=spGjDHJxF_dc|pcrid|88057073523|pkw||pmt||prd|1094089&gclid=CjwKEAjwxurIBRDnt7P7rODiq0USJADwjt5DsrXNeDRpKWl4Hp_9F8B1Wdn3flgG0m-1z0mgKscp_BoCiQzw_wcB

Get two V de G generators - one of each polarity.

 

 

You are not the first person I have heard say size doesn't matter. On one of my early posts on this thread I referenced current bunching points in switched circuits. Narrow pointed tips on antennae causes currents to bunch, causing very high impulse voltages. The electric field strength can explode wires, under the correct conditions. I was exploring the bifilar wound tesla coil pulsed at very high repletion rates so that an outgoing pulse passes an incoming pulse. I guess it is a little like an electronic Wilmhurst device.

 

Thankyou for your interest.

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I don't think that

 

Childs Law or Equation was explicitly mentioned in the book I referenced.

 

https://en.wikipedia.org/wiki/Space_charge

 

http://simion.com/definition/childs_law.html

 

https://www.britannica.com/science/Langmuir-Child-equation

 

What is it you don't think? If it was the size doesn't matter thing I was trying to be funny, it does matter.

 

In this case smaller is better, to concentrate any charges and increase the Electric Field Strength. Increasing the electric field strength may increase the space charge density

 

J = K Vd3/2 / d2

 

I haven't finished reading the book yet.? My missis keeps asking me to do things :)

 

I don't think the Wilmhurst device is suited to what I was originally thinking about. However I have not completely discounted it. I do see the potential it has for generating a useful potential momentarily.

 

Thank you for the links above, they are interesting

 

Ref anodes and cathodes and gaseous emissions, in all instances I have read so far only the electrons or -ve charges are mentioned. I am interested in the positively charged atoms also, and think they can be separated using a magnetic field, thus doubling the recoverable charge from the effective avalanche which will happen in gases, once the voltage is high enough. Also they will become excited an ionize more atoms.

 

On the above point thank you again for your references on the magnetohydrodynamic generator, it shows I am on the right track.

Edited by Handy andy

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What is it you don't think? If it was the size doesn't matter thing I was trying to be funny, it does matter.

 

 

No sweat,

 

"I don't think that the Child's equation was mentioned etc......."

 

So I posted some references.

 

:)

Edited by studiot

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You are not the first person I have heard say size doesn't matter.

What I said was

Size is not important ( to polarity)

And it was wrt Sensei's strange notion that "on bigger metallic sphere there is positive charge, ... Smaller metallic sphere will have negative charge,"

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And it was wrt Sensei's strange notion that "on bigger metallic sphere there is positive charge, ... Smaller metallic sphere will have negative charge,"

 

It was not "strange notion", but how "typical Van de Graaff generator is build and how it's working", f.e. mine.

If you would have Van de Graaff generator, you could check it, by yourself.

 

What I said was

Size is not important ( to polarity)

 

Size is important to charge.

As long as spheres are made of the same material with the same thickness,

larger sphere has larger area, larger mass, and large quantity of metal atoms, thus larger quantity of free electrons that can be torn off.

 

The most powerful Van de Graaff generator was entire building, with lab rooms with working scientists inside of it.

Edited by Sensei

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It was not "strange notion", but how "typical Van de Graaff generator is build and how it's working", f.e. mine.

If you would have Van de Graaff generator, you could check it, by yourself.

 

 

Size is important to charge.

As long as spheres are made of the same material with the same thickness,

larger sphere has larger area, larger mass, and large quantity of metal atoms, thus larger quantity of free electrons that can be torn off.

 

The most powerful Van de Graaff generator was entire building, with lab rooms with working scientists inside of it.

I do have a G se G.

I can set it up to charge the top electrode either positively or negatively.

So, in fact, your statement that ""on bigger metallic sphere there is positive charge, ... Smaller metallic sphere will have negative charge," is actually wrong

 

Why not just accept that?

 

Also the thickness of the material the spheres are made of makes no difference as long as it conducts.

 

Teachers should start by learning.

I used to live a few miles from one of the worlds biggest V De G.

Edited by John Cuthber

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Also the thickness of the material the spheres are made of makes no difference as long as it conducts.

 

Yeah, the charge all winds up on the outside surface anyway. And the time required for that to happen (charge relaxation time) if short compared to any other aspect of the physics of the situation (like 10^-16 seconds or something within an order of magnitude or two fo that).

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