is sort of physics is relevant to nanotechnology (and the subsequent issues of high-volume micromanufacture, etc.)...
The physics of things on small scales--yes, very useful for nanomaterials science. The physics of a quark-gluon plasma--not so useful for materials science. It takes multibillion-dollar instruments to make and detect these plasmas; they won't be finding their way into micromanufacturing for a looong time.
I wouldn't be surprised if it is eventually useful. Almost all fundamental research has found an application after enough time has passed. (The stuff for which we haven't found an application probably just hasn't been around long enough.) Nanotechnology, though, isn't where quark-gluon plasmas will come in handy. Nanotech works at energies that are much too low, and on length scales that are much too large.
Due to the Leidenfrost effect this might actually work, but it also might cause loss of teeth (seen it) tongue (seen pictures) or stomic [sic] (don't want to know).
I had a physics professor that did a slightly safer variant. You want to avoid a large thermal shock to the enamel of the teeth. The trick is to immerse a slice of (fairly dry) bread in LN2 for several minutes. It has been a while since I've seen it, but IIRC he crumbled the bread and tossed the chunks into his mouth. If you build up a good bit of saliva first, then the bread doesn't freeze patches of your mouth. The bread probably also slows down the conduction of heat away from the mouth, by insulating the inside of each chunk. Anyway, dramatic gouts of water vapour are produced when the demonstrator exhales.
It was popularly known as his 'breathing fire' demo. I wouldn't try this at home without consulting someone who knows what they're doing.
Feynman's story comes from Surely You're Joking, Mr. Feynman. As a boy, he would do science demos for friends and family.
The specific trick to which you allude involves dipping your hand in water and then quickly in benzene. The two liquids are pretty much insoluble in one another, so a (somewhat spotty) layer of water remains between your hand and the benzene layer. If you ignite the benzene, most of it doesn't burn in contact with the skin, and the water with its high specific heat soaks up most of the heat of combustion, so it doesn't hurt--in principle.
Feynman discovered that as an adult, the hairs on his hands would wick the benzene down into direct contact with his skin...and hurt like hell.
The high specific and latent heats of water permit a number of amusing tricks. For example, you can boil water over an open flame in a paper cup. The boiling water absorbs heat from the paper cup, keeping it at a warm (but nowhere near combusting) 100 C.
You can also mix roughly equal parts water and isopropyl alcohol to obtain a solution that will burn, but doesn't damage most inanimate materials. Again, the big latent heat of vaporization of water soaks up almost all of the heat generated by the combustion of the alcohol. You can soak a large-denomination bill in this stuff and 'burn' it. Hint: test the solution on something disposable, first.;)
Maybe its not the greatest thing ever (I don't know, never seen one in person), but for a brand new product that is not a ripoff I think its doing pretty well. How great was MacOs 1.0 compared to OSX?
Not really a fair comparison--the technology wasn't there twenty years ago to do, well, anything that OSX does today. A fair comparison would be between the first Mac OS (would that be System/Finder 1.0? I'm mostly a Windows/Sun/*nix guy) and Windows 1.0--for which on behalf of Bill Gates I am embarrassed.
Now, compare Segway with other modern modes of transportation. Except for a few niche uses, the Segway is more expensive, has less range, or is more dangerous than other available options. As a frequent pedestrian and cyclist, and semi-frequent driver, I find it difficult to see how the Segway could make my own life easier--or how Segways in the hands of others could fail to make my life more dangerous.
At least they admit they pulled the statistics out of their ass:
To reach the worldwide estimates, the researchers resorted to multiplying the U.S. statistics.
On the other hand, this probably does produce a reasonably conservative estimate. Precisely because there is a fondness in the United States for cute sea creatures, U.S. fishers are probably more careful about the harm they do to marine mammals. (Not because they're necessarily nicer people, but because their corporate masters fear crucifixion in the media.) Similarly, Canadian and European trawlers are probably also more considerate of 'cute' sea life.
Now that it has been used in this one case successfully, who doesn't think that it has the potential to be used in many more? Speeding? Stop signs?
Yep. Except that it can't be used for these cases. It only records five seconds of data, and only stops wiping the older stuff when the airbags inflate.
In other words, you have to have been in an accident for there to be any useful data collected. If you're doing 140 km/h on the highway, that record will be gone before the cop is finished pulling you over. There will only be a useful record if while speeding you crash into something.
'm glad he's off the streets as well, but I'm appalled at the technology being used this way. As for the manufacturers and accident investigators with some sort of interest in this sort of data...well screw 'em. There's nothing in the constitution that says it's my job to make another guy's job easier, even if I'm dead. I hate to use the term slippery slope because we all throw it around all the time here on Slashdot, but I don't see how this is any different from the TIA initiatives.
Ladies and gentlemen of Slashdot, please remove your tinfoil hats and place your seatback trays in the upright and locked position. This has nothing to do with TIA. Information about your driving (bad or otherwise) isn't broadcast to a central government clearinghouse. This system is very similar to (albeit a crippled version of) an aircraft flight recorder. Pilots don't refuse to fly because there's a black box, and nobody looks at the flight recorder data unless something goes wrong.
What was the driver doing in the five to ten seconds before an accident? This is a perfectly valid question to ask, and this system directly answers--unlike guesstimates based on physical evidence at the scene, and profoundly different from (usually) inaccurate eyewitness accounts.
Your right to privacy is not infringed. This device doesn't tell us about your trip to the pornography store, or your affair with the boss' secretary, or whether you were speeding over the last three months, or how you ran that red light last night because it was 3 a.m. and nobody was around. The only information available pertains to the time right before your accident. Methinks it is reasonable for the police to be interested in these data, and also reasonable for them to have permission to access it.
Face it--if there is any sort of serious auto accident, there will be a police investigation, and they will want to lay charges. This technology comes in really handy if you're in an accident that isn't your fault.
About a year ago, I was called out to do field service. When I got to the lady's house and was let in, the first thing I noticed was the smell of gunpowder. The second, the double barreled 12-gauge shotgun lying on the couch. Third, the big gaping hole in the side of her computer. (It was one of those Macs where the CPU and monitor are in the same housing.)
I looked at her. She was a little grey haired woman, around 60 or so. Had she? Not possible. Still, I had to ask.
Me: "Did you shoot...?"
Customer: "Yes, I got a little mad at it. They told me I couldn't hurt it, but I think they were wrong. Can you salvage anything?"
I mumbled something about not being a Mac tech and told her I would send one out as soon as I could. Then I burned rubber out of there.
About a month later, my boss called me in; he had the woman on hold. She had apparently complained that I was not competent and that I had lied when I said I would send out a competent Mac tech -- or perhaps I just hadn't been able to find anyone competent working for us. I filled him in. He paused for a second, picked up the phone, and said, "Ma'am? Did you put a shotshell into your computer?... Uh huh...I'm sorry, ma'am, we really can't...well, no.... I'll try to send one out.... Nice doing business with you...." He hung up, looked at me, and said, "You think any of our Mac techs will go?" I shook my head. "Me neither."
We heard from her again last week, when my boss told me that the woman had called up to cuss me out, saying not only was I a "young whippersnapper" but also a liar, since one of our competitors had fixed her computer just fine, even fixing the little scratches and stuff on the monitor glass. That sounded fishy, so I went over and talked with the techs. After a case of canned drinks and a few bags of junk food, I wormed the whole story out of them. Apparently, about the only salvagable part was the hard drive (which the buckshot had missed), so they took it out, went out and bought a whole new computer, slapped the hard drive in, and presented it to the lady as her repaired computer -- of course charging her an arm and a leg.
Re:More accidents?
on
42-Volt Autos
·
· Score: 2, Funny
My aunt and uncle were driving on one of the major highways in Toronto (the 401, I think) and saw a car weaving back and forth in its own--and adjacent--lanes.
While (very carefully) passing this car, they observed the driver knitting.
They may still be an 800-pound gorilla, but gorillas don't fare very well against a well-trained sharpshooter (read: IBM).
I'm not sure if that's an appropriate analogy. IBM is still the bigger metaphorical fish in this sea. The lesson here will be
Even 800 pound gorillas are usually smart enough to not fuck with big, well-trained, sharpshooting blue elephants.
Re:It Took Them 56 Years to do What?
on
Roswell Declassified
·
· Score: 2, Insightful
It took them 56 years to say that nothing happened. Yeah, right.
Ask a Pentagon official about something classified. Go ahead. Try it. The answer you get will be along the lines of "We can neither confirm nor deny..."
If they said, "Well, I guess it won't hurt this time to tell you that nothing really much happened at Roswell, and we classified our investigation because we were embarrassed to waste all that time and money..." What would you think? The next time you ask a question and don't get more information, you can think "Ah hah! They're really hiding something good, now! If there was nothing to this story, they would say so." And so the whole 'neither confirm nor deny' practice goes out the window.
I'd say that they managed to hide the development and creation of a nuclear weapon, on a project with thousands of staff, pretty well.
...for a few years, during wartime, when many civil liberties were suspended, and most people were too busy building airplanes or dying in trenches to worry about conspiracy theories. And even then foreign governments had spies within the Manhattan project. (See Klaus Fuchs, for example.)
Even then, security on the Manhattan project suffered from occasional comical lapses. Richard Feynman's Surely You're Joking, Mr. Feynman recounts some amusing incidents.
Should this be blamed on outsourcing to foreign countries, or does it have something to do with the time spent complaining about outsourcing on Slashdot?
According to the article the MIDDLE class citizen makes 1000 pounds a year. Just
the cable subscription would represent 5% of their income.
Why do they need a cable subscription? In many parts of the world, it is still possible to receive television signals using decades-old wireless technology. Also, since televisions were banned until recently I wouldn't expect much of the country to be wired with cable to every home.
Heck, I live in Canada (generally considered a developed nation), and I've only had cable for a couple years of my life--and then only because my landlords were already paying for it. No, the people of Bhutan mostly can't afford to buy cable--but they don't need it. I wouldn't be surprised if a significant number of people who watch television don't own one, either. They probably visit a friend that does.
Carbohydrate-based plastics actually pull CO2 out of the air as plants grown (good), but if they do decompose, the carbon is released as methane gas, which is actually a more powerful greenhouse warming gas than CO2 (bad).
Not always true, by any means. If the stuff is decomposed by healthy aerobic bacteria and associated critters, then the decomposition of the corn-based products should result in mostly water and carbon dioxide--which you take out of the air when you grow more corn.
The problem is landfill disposal. Under conditions of poor air circulation, anaerobic bacteria are responsible for almost all decomposition, and they do produce methane--and an number of additional foul-smelling byproducts, too. (Actually, this bioplastic won't degrade in a landfill--virtually nothing does, because of the tight packing and lack of ready air and water circulation. Newspapers are regularly excavated from old landfill sites bearing completely legible fifty-year-old stories.)
If our garbage were shredded, then stirred regularly to encourage aerobic decomposition, methane would be a non-issue. Actually, you won't have appreciable methane production if you just throw this stuff out on open soil or waters...though it wouldn't be pretty.
I don't know about anyone else, but when weighing, lasering, or vibrating things... using my nose is one of the last options I'd consider"
The trick is this. You coat the bar with something chemically 'sticky', then you blow sample gas past it. Any target molecules present adhere to the bar and presto! You have a nose. Obviously, you would have to have an array of these little bars, each coated with a different 'glue'. Exposure to a particular compound would (ideally) lead to a unique 'spectrum' of weights recorded.
This might not be such a bad idea. Create a Slashbox for all the SCO stories. Everything--duelling press releases, sneezes from Reuters, the whole shebang. People with nothing better to do can follow it religiously, while everyone else can disable that Slashbox and move on with their lives.
Permit the editors to post one story to the main page every two weeks, at most.
I'd rather go on "slower" simpler hardware that does a very specific job... and you can repair with a soldering iron.
The problem is that all of the Mars shots we've launched so far--and all of the failures referred to--have been unmanned probes. So the question remains: how do you plan to get the guy with the soldering iron up there?
How about this? We're launching fairly small, very complex probes, that aim to do a lot more than the moon missions in some respects...certainly the craft are responsible for accomplishing a lot more 'unsupervised'.
With the moon missions, there were manned craft, and so every line of code had to be checked and rechecked--and hundreds of guys were on the ground watching everything that happened, twenty-four seven, until the astronauts were safely back on the ground.
Now, windows for a Mars launch come much less frequently. There might be a temptation to rush some of the QA and just cross fingers. Speed of light delay means that NASA can't intervene in most situations--problems are resolved one way or another before anyone on the ground even hears about them.
Moon launch hardware had to last for a few days in space--stressful, busy, lengthy days, but a few days nonetheless. We expect Mars craft to spend months in hard vacuum and harder radiation, and then land successfully without human help, on a planet with higher gravity than the moon...
Just some thoughts. The parent is right--Mars missions are hard because it's far away, and you have to travel through space to get there.
Erm. I dunno. For a lot of laypeople, a valve with no 'solid' parts fits the definition of a 'force field'.
(Note: I am embarrassed to use the following example.) Take the brig on Star Trek: TNG era vessels. There is a ring of emitters surrounding the door opening. These emitters are presumably responsible for maintaining an impenetrable field in the doorway. That 'force field' seems to be at least loosely similar (in form and stated goals) to the 'plasma valve' described--it's just larger.
Oh, and the plasma valve would take your finger off if you touched it. Oh well. This is real life that we're stuck with, after all.
Plutonium parts ("the pit") of the core of nuclear bomb as well as the depleted uranium-tipped ammunition is always electroplated with a thin layer of another metal (nickel, for example) to prevent people from getting "radiation burns" on the skin of their hands when handling these alpha emiting materials.
As I understand it, it actually doesn't have to do with direct radiation burns. When alpha decay takes place, a sizable amount of kinetic energy is divided up between the alpha particle and the remaining atomic nucleus. Sometimes the decay gives the remaining nucleus a sufficient kick in the right direction for it to come loose from the surface. This decay product is often radioactive as well, so instead of dealing with a solid lump of plutonium (bad enough) you also have radioactive dust on surrounding surfaces and in the air. Sealing the surface contains these decay products.
As well, plutonium is even more toxic as a chemical poison than as a radioactive one--coating the parts makes sense just to prevent contact with it.
Finally, pure plutonium is (IIRC) a fairly reactive metal. Electroplating it prevents it from oxidizing--you don't want your nuclear warheads to get 'rusty', do you?
Radiation burns from the alpha emission are actually relatively unlikely--even the most careless handler of plutonium would be wearing rubber gloves, and a sensible soul works in a shielded glove box full of inert gas. This is more than sufficient to stop any alpha particles.
Slashdot Mirror
The physics of things on small scales--yes, very useful for nanomaterials science. The physics of a quark-gluon plasma--not so useful for materials science. It takes multibillion-dollar instruments to make and detect these plasmas; they won't be finding their way into micromanufacturing for a looong time.
I wouldn't be surprised if it is eventually useful. Almost all fundamental research has found an application after enough time has passed. (The stuff for which we haven't found an application probably just hasn't been around long enough.) Nanotechnology, though, isn't where quark-gluon plasmas will come in handy. Nanotech works at energies that are much too low, and on length scales that are much too large.
I had a physics professor that did a slightly safer variant. You want to avoid a large thermal shock to the enamel of the teeth. The trick is to immerse a slice of (fairly dry) bread in LN2 for several minutes. It has been a while since I've seen it, but IIRC he crumbled the bread and tossed the chunks into his mouth. If you build up a good bit of saliva first, then the bread doesn't freeze patches of your mouth. The bread probably also slows down the conduction of heat away from the mouth, by insulating the inside of each chunk. Anyway, dramatic gouts of water vapour are produced when the demonstrator exhales.
It was popularly known as his 'breathing fire' demo. I wouldn't try this at home without consulting someone who knows what they're doing.
The specific trick to which you allude involves dipping your hand in water and then quickly in benzene. The two liquids are pretty much insoluble in one another, so a (somewhat spotty) layer of water remains between your hand and the benzene layer. If you ignite the benzene, most of it doesn't burn in contact with the skin, and the water with its high specific heat soaks up most of the heat of combustion, so it doesn't hurt--in principle.
Feynman discovered that as an adult, the hairs on his hands would wick the benzene down into direct contact with his skin...and hurt like hell.
The high specific and latent heats of water permit a number of amusing tricks. For example, you can boil water over an open flame in a paper cup. The boiling water absorbs heat from the paper cup, keeping it at a warm (but nowhere near combusting) 100 C.
You can also mix roughly equal parts water and isopropyl alcohol to obtain a solution that will burn, but doesn't damage most inanimate materials. Again, the big latent heat of vaporization of water soaks up almost all of the heat generated by the combustion of the alcohol. You can soak a large-denomination bill in this stuff and 'burn' it. Hint: test the solution on something disposable, first. ;)
Not really a fair comparison--the technology wasn't there twenty years ago to do, well, anything that OSX does today. A fair comparison would be between the first Mac OS (would that be System/Finder 1.0? I'm mostly a Windows/Sun/*nix guy) and Windows 1.0--for which on behalf of Bill Gates I am embarrassed.
Now, compare Segway with other modern modes of transportation. Except for a few niche uses, the Segway is more expensive, has less range, or is more dangerous than other available options. As a frequent pedestrian and cyclist, and semi-frequent driver, I find it difficult to see how the Segway could make my own life easier--or how Segways in the hands of others could fail to make my life more dangerous.
On the other hand, this probably does produce a reasonably conservative estimate. Precisely because there is a fondness in the United States for cute sea creatures, U.S. fishers are probably more careful about the harm they do to marine mammals. (Not because they're necessarily nicer people, but because their corporate masters fear crucifixion in the media.) Similarly, Canadian and European trawlers are probably also more considerate of 'cute' sea life.
Yep. Except that it can't be used for these cases. It only records five seconds of data, and only stops wiping the older stuff when the airbags inflate.
In other words, you have to have been in an accident for there to be any useful data collected. If you're doing 140 km/h on the highway, that record will be gone before the cop is finished pulling you over. There will only be a useful record if while speeding you crash into something.
Ladies and gentlemen of Slashdot, please remove your tinfoil hats and place your seatback trays in the upright and locked position. This has nothing to do with TIA. Information about your driving (bad or otherwise) isn't broadcast to a central government clearinghouse. This system is very similar to (albeit a crippled version of) an aircraft flight recorder. Pilots don't refuse to fly because there's a black box, and nobody looks at the flight recorder data unless something goes wrong.
What was the driver doing in the five to ten seconds before an accident? This is a perfectly valid question to ask, and this system directly answers--unlike guesstimates based on physical evidence at the scene, and profoundly different from (usually) inaccurate eyewitness accounts.
Your right to privacy is not infringed. This device doesn't tell us about your trip to the pornography store, or your affair with the boss' secretary, or whether you were speeding over the last three months, or how you ran that red light last night because it was 3 a.m. and nobody was around. The only information available pertains to the time right before your accident. Methinks it is reasonable for the police to be interested in these data, and also reasonable for them to have permission to access it.
Face it--if there is any sort of serious auto accident, there will be a police investigation, and they will want to lay charges. This technology comes in really handy if you're in an accident that isn't your fault.
About a year ago, I was called out to do field service. When I got to the lady's house and was let in, the first thing I noticed was the smell of gunpowder. The second, the double barreled 12-gauge shotgun lying on the couch. Third, the big gaping hole in the side of her computer. (It was one of those Macs where the CPU and monitor are in the same housing.)
I looked at her. She was a little grey haired woman, around 60 or so. Had she? Not possible. Still, I had to ask.
I mumbled something about not being a Mac tech and told her I would send one out as soon as I could. Then I burned rubber out of there.
About a month later, my boss called me in; he had the woman on hold. She had apparently complained that I was not competent and that I had lied when I said I would send out a competent Mac tech -- or perhaps I just hadn't been able to find anyone competent working for us. I filled him in. He paused for a second, picked up the phone, and said, "Ma'am? Did you put a shotshell into your computer? ... Uh huh...I'm sorry, ma'am, we really can't...well, no.... I'll try to send one out.... Nice doing business with you...." He hung up, looked at me, and said, "You think any of our Mac techs will go?" I shook my head. "Me neither."
We heard from her again last week, when my boss told me that the woman had called up to cuss me out, saying not only was I a "young whippersnapper" but also a liar, since one of our competitors had fixed her computer just fine, even fixing the little scratches and stuff on the monitor glass. That sounded fishy, so I went over and talked with the techs. After a case of canned drinks and a few bags of junk food, I wormed the whole story out of them. Apparently, about the only salvagable part was the hard drive (which the buckshot had missed), so they took it out, went out and bought a whole new computer, slapped the hard drive in, and presented it to the lady as her repaired computer -- of course charging her an arm and a leg.
While (very carefully) passing this car, they observed the driver knitting.
I'm not sure if that's an appropriate analogy. IBM is still the bigger metaphorical fish in this sea. The lesson here will be
Ask a Pentagon official about something classified. Go ahead. Try it. The answer you get will be along the lines of "We can neither confirm nor deny..."
If they said, "Well, I guess it won't hurt this time to tell you that nothing really much happened at Roswell, and we classified our investigation because we were embarrassed to waste all that time and money..." What would you think? The next time you ask a question and don't get more information, you can think "Ah hah! They're really hiding something good, now! If there was nothing to this story, they would say so." And so the whole 'neither confirm nor deny' practice goes out the window.
Even then, security on the Manhattan project suffered from occasional comical lapses. Richard Feynman's Surely You're Joking, Mr. Feynman recounts some amusing incidents.
Should this be blamed on outsourcing to foreign countries, or does it have something to do with the time spent complaining about outsourcing on Slashdot?
Why do they need a cable subscription? In many parts of the world, it is still possible to receive television signals using decades-old wireless technology. Also, since televisions were banned until recently I wouldn't expect much of the country to be wired with cable to every home.
Heck, I live in Canada (generally considered a developed nation), and I've only had cable for a couple years of my life--and then only because my landlords were already paying for it. No, the people of Bhutan mostly can't afford to buy cable--but they don't need it. I wouldn't be surprised if a significant number of people who watch television don't own one, either. They probably visit a friend that does.
Not always true, by any means. If the stuff is decomposed by healthy aerobic bacteria and associated critters, then the decomposition of the corn-based products should result in mostly water and carbon dioxide--which you take out of the air when you grow more corn.
The problem is landfill disposal. Under conditions of poor air circulation, anaerobic bacteria are responsible for almost all decomposition, and they do produce methane--and an number of additional foul-smelling byproducts, too. (Actually, this bioplastic won't degrade in a landfill--virtually nothing does, because of the tight packing and lack of ready air and water circulation. Newspapers are regularly excavated from old landfill sites bearing completely legible fifty-year-old stories.)
If our garbage were shredded, then stirred regularly to encourage aerobic decomposition, methane would be a non-issue. Actually, you won't have appreciable methane production if you just throw this stuff out on open soil or waters...though it wouldn't be pretty.
The trick is this. You coat the bar with something chemically 'sticky', then you blow sample gas past it. Any target molecules present adhere to the bar and presto! You have a nose. Obviously, you would have to have an array of these little bars, each coated with a different 'glue'. Exposure to a particular compound would (ideally) lead to a unique 'spectrum' of weights recorded.
This might not be such a bad idea. Create a Slashbox for all the SCO stories. Everything--duelling press releases, sneezes from Reuters, the whole shebang. People with nothing better to do can follow it religiously, while everyone else can disable that Slashbox and move on with their lives.
Permit the editors to post one story to the main page every two weeks, at most.
Never test for an error condition you don't know how to handle. -- Steinbach
The problem is that all of the Mars shots we've launched so far--and all of the failures referred to--have been unmanned probes. So the question remains: how do you plan to get the guy with the soldering iron up there?
With the moon missions, there were manned craft, and so every line of code had to be checked and rechecked--and hundreds of guys were on the ground watching everything that happened, twenty-four seven, until the astronauts were safely back on the ground.
Now, windows for a Mars launch come much less frequently. There might be a temptation to rush some of the QA and just cross fingers. Speed of light delay means that NASA can't intervene in most situations--problems are resolved one way or another before anyone on the ground even hears about them.
Moon launch hardware had to last for a few days in space--stressful, busy, lengthy days, but a few days nonetheless. We expect Mars craft to spend months in hard vacuum and harder radiation, and then land successfully without human help, on a planet with higher gravity than the moon...
Just some thoughts. The parent is right--Mars missions are hard because it's far away, and you have to travel through space to get there.
What, do they refuse to ask for directions or something? ;)
No, but you can mow the lawn with it. ;)
Erm. I dunno. For a lot of laypeople, a valve with no 'solid' parts fits the definition of a 'force field'.
(Note: I am embarrassed to use the following example.) Take the brig on Star Trek: TNG era vessels. There is a ring of emitters surrounding the door opening. These emitters are presumably responsible for maintaining an impenetrable field in the doorway. That 'force field' seems to be at least loosely similar (in form and stated goals) to the 'plasma valve' described--it's just larger.
Oh, and the plasma valve would take your finger off if you touched it. Oh well. This is real life that we're stuck with, after all.
The nitpick is appreciated--and appropriate, since I'm discussing points of law and contract details. You are quite right. Mea culpa.
As I understand it, it actually doesn't have to do with direct radiation burns. When alpha decay takes place, a sizable amount of kinetic energy is divided up between the alpha particle and the remaining atomic nucleus. Sometimes the decay gives the remaining nucleus a sufficient kick in the right direction for it to come loose from the surface. This decay product is often radioactive as well, so instead of dealing with a solid lump of plutonium (bad enough) you also have radioactive dust on surrounding surfaces and in the air. Sealing the surface contains these decay products.
As well, plutonium is even more toxic as a chemical poison than as a radioactive one--coating the parts makes sense just to prevent contact with it.
Finally, pure plutonium is (IIRC) a fairly reactive metal. Electroplating it prevents it from oxidizing--you don't want your nuclear warheads to get 'rusty', do you?
Radiation burns from the alpha emission are actually relatively unlikely--even the most careless handler of plutonium would be wearing rubber gloves, and a sensible soul works in a shielded glove box full of inert gas. This is more than sufficient to stop any alpha particles.