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Force Fields And Plasma Shields Get Closer
one2boo writes: "I guess watching countless hours of Star Trek has paid off for Mounir Laroussi, an electrical and computer engineer at Old Dominion University in Norfolk, Va. Space.com writes: 'Laroussi has literally put plasma on the table: devising an apparatus that creates a mini-plasma inside a Plexiglas cube by passing an electric current through helium gas via specially calibrated electrodes.' This advance in 'Plasma Shields' will allow the shielding and cloaking of satellites and spacecraft. Low-temperature plasmas could one day also make possible an entire new generation of miniature lasers and ultra-low-energy fluorescent light tubes. You can read more on this story here." And for some reason, the relatively low power requirements remind of me of the guts of the Improbability Drive.
Mr. McGuire: I just want to say one word to you... just one word.
Benjamin Braddock: Yes, sir.
Mr. McGuire: Are you listening?
Benjamin Braddock: Yes, sir I am.
Mr. McGuire: "Plasma."
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Let me know when I can get my own personal force-field. Hmm.. if they get thin enough and are not hot, we could have plasma condoms.
Remember kids. You shouldn't be having sex out of wedlock. But if you do end up doing it, remember to play it safe. Shields Up!
Ok.. I already doffed my extra point. That's one less that you moderators will get from me! Ha Ha Ha!
It's not enough to bash in heads, you've got to bash in minds. - Captain Hammer
Did anyone else make the connection that these things are a lot like the personal shield things in Dune? They stop energy blasts and whatnot, but bullets and knives are still able to penetrate.
Kinda similar except for the fact that in Dune, the fields stopped anything that was moving quickly too, so you had to slowly slip the knife into the field to kill someone.
Yum!
Rami James
Guy with sand in his pants.
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rJames.org - illustration
Tinkering with things we don't quite understand and learning about them can lead to all sorts of breakthroughs and new understanding that can help in many other areas. Look at all the cool stuff that has come out of NASA's research. A lot of it really has helped people. It's not just screwing around.
Besides, there are many people researching cancer and other such things. But it would be silly to have everybody doing that sort of research. Then once it's cured, we're stuck with a bunch of biologists and such with nothing to do and then we have to send them back to school to learn how to be computer help-desk workers or something. It would be a sad, sad world.
It's not enough to bash in heads, you've got to bash in minds. - Captain Hammer
First, protecting space vehicles from microdebris. This would be the single most useful space application of this technology for sattelites, shuttles, etc., as dust particles tend to hurt metal a lot if they're travelling at relative speeds of thousands of miles per hour. Since the terrestrial version of this thing has to be contained, however, I don't know if this is possible.
Second, fusion reaction containment. Since several plans for fusion technology seem to involve rather large heat generation, it'd be nice if this could be used to absorb the heat generated by the reaction and transmit it to generator equipment more safely (i.e. without frying the container). If the plasma is guided by magnetic fields (like so many things are), the extra energy should push the plasma bubble bigger, which can be used to induce currents directly. I'm guessing that this isn't a new idea, but I still think it's worth mentioning, especially since this would theoretically be one of the more efficient fusion->electricity conversions.
Either of these would be a huge advance (along with the rest of the stuff mentioned), so this is an impressive development indeed!
"Time flies like an arrow; fruit flies like a banana." --Groucho Marx
I'm only pointing this out to you, grammar nazi, because I want you to be the best damn grammar nazi you can be!
Anything can be used for military applications, no matter how useful it is for benevolent endevours. If the fact that an invetion could potentially have a military "use" automatically means that moral scientists should avoid it like the plague, then the only "moral" scientists are those who limit themselves to stone knives and bearskins. (No, wait, stone knives can be used to kill people, too. I guess you're stuck with the bearskin, if you can get it away from the bear without using a stone knife, that is.)
--GrouchoMarx
--GrouchoMarx
Card-carrying member of the EFF, FSF, and ACLU. Are you?
Yes, I watch too much Star Trek myself, why do you ask? :-)
--GrouchoMarx
--GrouchoMarx
Card-carrying member of the EFF, FSF, and ACLU. Are you?
DCUP spokesperson Dr Eric Mbunge sees a bright future for the penal application of cold plasmas. "With this technology we could execute prisoners by the batch, instead of one at a time," explains Dr Mbunge. "There would be this purple glow, and they'd all fall to the floor. Dead. It would be just like Star Trek."
When it was pointed out that Star Trek does not feature executions, Dr Mbunge responded, "It would if it was set in Texas."
The Department of Cruel and Unusual Punishments has not developed any new execution technologies since the introduction of the lethal injection in 1974. Its 1984 invention, the "microwave chair", was never used in Texas prisons because of fears that it might cause adverse health effects to prison wardens.
$ cat < /dev/mouse
Excuse me, but to my understanding the ordinary neon fluorescent lamps also contain "plasma" (when they are lit), caused by "electric current vis specially calibrated electrodes"....
The article has a rather high hype-to-explanation ratio... so I went looking for the patent they mention. Not so technical as to be incomprehensible, and more useful than the article, IMO. My first impression is that the advance here is the impedance matching system used to maintain the plasma, which allows the compact equipment and low power requirements. (I suppose it searches for the natural resonance of whatever ions you have between the electrodes... just find the lowest-energy state/standing wave at which it remains permittive/permeable.) And if you have low power plus no sealed chamber (1 atm, random molecular gases allowed), it pretty much follows that the result is a low temperature plasma, since plasma tends to radiate continuously. The scalability aspect is nice too... good for more than a toy.
Either I'm misunderstanding something, or the sterilization is done by the radiation from the plasma... basically just using the plasma as an efficient UV lamp. (The sterilization patent talks about sterilizing liquids or gels up to 2cm deep... I can't see doing that with the surface interactions, which might be sufficient for polished tools and the like.) This doesn't appear to be sufficient for a low-volume irradiation system for food, which is unfortunate, because I like my hamburgers juicy. Oh well. (Of course, prions survive irradiation anyway, so I would still have to worry about BSE.)
There is also a separate patent for "surface shielding". Might be fun to set up on your car :) I'm having trouble figuring out how the leakage from this system would be less detectable than the reflected radio waves it would disperse, though... I suppose if you do it right, all the radiation is absorbed by the gases you are ionizing?
Java: the COBOL of the new millenium.
So does this mean that the first the policeman manning the radar speed trap will see is this purple blur flying past at 200km/h?
I want one!
If my call is important, why am I talking to a recording?
The Mongrel Dogs Who Teach
I don't see how this could be used to cloak/shield a satellite - Space is a vacuum, and hence all of the precious gas would leak. Plus this needs two large (read: radar-reflecting) plates on the sides.
BUT - From what I recall, among other things the maximum power for a given laser is proportional to the number of excited atoms capable of radiating, i.e. the density of the gas in the case of a gas laser. With this kind of plasma-generating scheme, you would need a far smaller laser to get the same amount of power (Or conversely, you could get far more power out of currently-sized lasers).
The patent applications don't mention the use of carbon dioxide as a gas to generate plasma from - But I'm willing to bet that unless there is some strange property of CO2 that prevents this from working (probably not, given the variety of other gases listed), CO2 has been tried.
Carbon dioxide is one of the best gases for making high-power lasers. CO2 lasers are much more efficient than most other gas lasers, and are the easiest way for an amateur (or relative amateur, you still need glass-blowing skills...) to make a high-powered laser capable of cutting through numerous materials. (CO2 lasers are well within the range of a serious hobbyist, as opposed to some of the more exotic lasers in existence.)
retrorocket.o not found, launch anyway?
Thanks a lump for furthering the stereotype that Texans are a bunch of unremorseful, 6-gun wielding cowboys who have nothing better to do than kill things.
I know humor is a difficult concept, particularly for the humor impaired, but try to follow me here:
Texas has an execution wielding, social throwback of a presidential candidate in the form of "dub uh yuh", which they want to inflict upon the rest of the country. This raises public awareness of Texas and its social policies, which are by most people's definition very far to the right (many would say "extreme").
Better get used to the stereotyping. The govorner of Texas and his policies have made Texas ripe for it, just as the Kansas school board made Kansas ripe for their brand of stereotyping.
No one seriously thinks all Texans are idiots, but that won't stop any of us from mocking their more blatant absurdities, and a blood thirsty penal system coupled with draconian laws (at least one couple recently served time in Texas for living together unmarried, and at least a couple of people are serving life without parole for selling hemp of all things) is a better reason than most.
As long as Texas insists on behaving like a collective political and social idiot, with throwback social policies remeniscent of the 19th century, the rest of us will continue to snicker.
The Future of Human Evolution: Autonomy
"Cold plasmas can cloak satellites and spacecraft from radar view and shield against attack from
certain kinds of energy weapons."
Hmm -- maybe we should work on developing those Energy Weapons before we start shielding our satellites against them?
Hear hear. George W. Bush puts the "goober" back in "gubernatorial."
...how is this any different from the "plasma ball" device, which has been on the shelves of novelty shops for years, and which operates by passing an electric current through an inert gas contained within a plexiglas bulb?
The Tyrrany Begins....
Finding God in a Dog
Hmm... I don't know too much about the CO2 lasers, all I recall is that they're much more efficient/powerful than most others.
If ionization of some sort is not how CO2 lasers work, what is the mechanism? They're not light-pumped, the gas is definately excited by the electrical current...
Of course, if only a portion of the gas is ionized, it could be less efficient, since I recall the amount of amplification is proportional to the difference in the amounts of excited and ground-state ions... So there could be more ionized molecules, but even more non-ionized molecules sapping the efficiency.
Wish I had my EE 306 notebook with me...
retrorocket.o not found, launch anyway?
Or more accurately, if someone loses their life in a violent crime, someone else is going to lose theirs. If it happens to be the person that committed the crime, that's a bonus, but that only happens in about 50% of cases.
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E_NOSIG
I just think it's sad that when I introduce myself as being from Texas, the usual response is "oh, so what do you think about the death penalty?"
:-)
Believe it or not I know how you feel. As an American who lived in Germany for a number of years (exchange student, summer intern, itinerant traveler), when I would admit to being American I was generally asked the same question (or some other stereotyped variation).
What most Americans don't realize is that, as Texas is to the United States, so to is the United States to the rest of the world.[1]
We'd better just develop a sense of humor about it, because everyone else certainly has.
[1] I think it is Robert Anton Wilson whom I am paraphrasing there, something about Texans being emberrassed about a (fictional) town called Bad Ass, while Americans in turn were emberrassed by Texas, while the Earth in turn was emberrassed by America.
The Future of Human Evolution: Autonomy
Quoted from article:
Laroussi's process, specified in pending patent applications, is scalable; cold-plasma containers of virtually any size are feasible.Okay, I was about to poo-poo the article at this point, since it seemed like it was about neon signs.
Not that neon signs aren't interesting or neat, it's just that when Crookes invented his first discharge tube in the late 1800s, it was news. But it isn't now.
A neon sign; or one of those neat little high-voltage fireglobe things you can buy at The Sharper Image; argon, helium-neon and carbon dioxde lasers already use cold plasma at their cores, crystal lasers like ruby and YAG:ND use xenon strobes (cold plasma) to excite them. For that matter, the strobe lights in a dance bar or the electronic flash on your camera. Even the tiny little NE-2 and NE-2H glow lamps you can buy at Radio Shack for $2 are perfect examples of cold plasma, and as the array of devices I've listed will demonstrate, it's already very versatile and scalable.
Changing the gases inside the device will change the colors. Neon is usually an orangy-red, argon is green, etc. Different mixes of the gases (usually noble (inert)) will result in different electrical and optical properties.
No vacuum pumps are required, since the plasma is generated at normal atmospheric pressure.This is the part that finally made me stop, with some interest.
Plasma is easily creatable both in a vacuum and at atmospheric pressure. All you really need to do is excite a gas, generally using high voltage electricity. The higher the pressure of the gas, generally the higher the voltage required to excite it actually is.
Simply walking across a rug on a dry day and having static electricity jump from your fingertip is a wonderful display of atmospheric pressure plasma. But, like lightning, it's hot; if the spark were continuous, it would eventually burn you.
(As one example, I've built dozens of tesla coils as a hobby, and it's fun to pull a spark off the top of them, using only your fingertip (use proper safety precautions if you try this). That's a great example of atmospheric pressure plasma. But the problem is, it gets damned hot if it arcs for too long to any given spot on your body.)
Consider the temperature of lightning. Fine, there's less energy involved here, so the temperature is less. But I can still pull an arc from my favorite tesla coil, using my fingertip, and then use my other hand to move pieces of paper into the arc. The paper catches fire almost immediately.
Cold plasma exists in neon lightbulbs and numerous other devices. But, at atmospheric pressure it's quite a development. I can't wait to play with it.
Fire and Meat. Yummy.
My source is a (possibly misremembered) report on convicted murderers awaiting execution where DNA evidence was not brought forward in the trial, but DNA testing was subsequently done. Texas, it should be noted, does not allow this, but several other states do, notably Illinois, which now has a moratorium on executions.
So my quote was a little over-generalized. I should have said that 50% of death row inmates who did not have a DNA test at the time of the trial, but did have a DNA test subsequent to conviction, are innocent.
The fact remains that if you are falsely accused of murder, your best chance of getting off is if the real murderer left some DNA behind.
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E_NOSIG