I'm not surprised that these folks didn't find anything, considering the sheer volume of images that's being transferred on the net each day.
Perhaps they were looking in all the wrong places to begin with. I would assume that if these terrorists use steganography to transmit messages, they would do so via a few selected channels. Perhaps they simply use e-mail to send the images, or some obscure binaries newsgroup.
Check out Icepick.com. They wired their entire house onto the net, including their:
Doorbell usage
Frontdoor camera
Trashbin scanner
Cat tracker
Microwave usage
Fridge openings and temperature
Phone usage
and yes: Toilet usage
They measure how often the toilet gets flushed, and for how long (I guess you can work out statistics on "difficult flushing jobs":-). They also measure the temperature in the place; around 14.5 C (58.1 F). Not really a place you want to hang out for too long...
kind of like the question "where do hydrocarbons, sulfates, and nitrates come from when running my car?"
Not at all like that. As edremy already pointed out, those products are all accounted for in the combustion of fuel.
Incomplete combustion is nonsense: it doesn't form HF, as there is no hydrogen present in Teflon. Impure samples/contamination of oxygen supply: if this would be the case in any appreciable amount, then there still is no proper reaction path to form HF.
Burning Teflon (i.e. reaction with O2) will give you all sorts of toxic fluorinated compounds, but I don't see how you get HF (hydrogen fluoride) out of this.
While it is correct that the reaction between bleach and ammonia forms hydrazine, this is not the most dangerous product. The following reactions are occuring:
(1) NH3 + NaOCl = NaOH + NH2Cl
(2a) NH3 + NH2Cl + NaOH = N2H4 +NaCl + H2O
(2b) 2 NH2Cl + N2H4 = NH4Cl + N2
Reaction (2b) is a cometing reaction to (2a), and it is actually catalyzed by the formation of hydrazine (N2H4, not N2H2 as you stated). This means that only a small amount of hydrazine is formed.
The dangerous product in this case is NH2Cl, chloramine gas. This stuff is very bad for your mucous membranes, and can easily kill you when inhaled.
Hydrazine is dangerous stuff too, though. It is a strong reducing agent, is easily adsorbed through your skin, and it is carcinogenic. I work with this compound in the chemistrylab, and the label says that it's a threat to health and life at concentrations as low as 80 ppm.
In my experience as a teaching assistant, professors often grade the students' performance on a bell curve. That means that there is no absolute scale that determines the cutoff between an A and a B, but a relative scale. You are graded relative to your fellow students' performance.
For instance, the professor ranks all the students from high to low, and the top 10% gets an A. Not fair? Too bad, that's the way many professors do it.
This is the kind of comment that could only be made by a narrow-minded engineer who lacks any appreciation of the state of modern biology. The naivete expressed here is rather appalling.
Calm down now. There is not one single discipline that will solve all our world's problems (whether that's in medicine, energy, environment or whatnot). Any further advancements can only be made by inter disciplinary research. Biology and medicine have made great advances with the aid of other disciplines as well: chemistry, physics (e.g. microscopy), and yes engineering (e.g. combinatorial chemistry).
No, engineers by themselves will not find a way to eradicate HIV. But when you're talking about the state of modern biology, we're not exactly sure how to solve the problem. We know on what wall the dartboard is, but blindfolded it is difficult to hit. Nanomachines may not be the best approach, and medicine will probably find a solution before these machines are operational. That doesn't mean it is wasted research money, since there are plenty of alternative applications.
You're correct that we are still FAR away from any useful nanomachines-- if it ever proves feasible. We know how to drag along a few atoms over a surface under very controlled conditions, but we don't know how to make assemble functional 3-dimensional structures. Self-assembly is nice, but it will undoubtedly involve the construction of some very complex building blocks.
The major source of helium is natural gas fields. Natural gas contains about 2% helium.
While it is true that the US supplies 80% of the world's consumption, this is NOT because helium isn't found in other gas fields around the world. The U.S. can run their production plants cheaper than other countries. It still takes some effort to separate the helium from natural gas and other components (especially hydrogen). The U.S. is also one of the largest (if not THE largest) consumer of helium.
Helium COULD also be distilled from air (cryogenic distillation), but since there is only 0.0005% helium in air, this is too costly for now. However, it would be MUCH cheaper than getting it from the moon. I don't think cryogenic distillation from will ever be competitive with recovery from natural gas, but it's certainly a better alternative than getting it from the moon.
Many people have investigated ways to incorporate or directly synthesise nanocrystals inside zeolites. Zeolites are large, open aluminosilicate structures that may act as a good framework for this. They contain cages that can control the size of the nanocrystals. Also, the cages are at fixed distance, and connected by pores (tunnels). The good thing is that you can make a wide variety of zeolites that have different geometries.
There was a very big interest in putting Cadmium sulfide inside zeolites. But it's not all that simple to get the crystals in place, and plugging the holes with sulfur is a big problem. Also, IF this works, no one knows how to incorporate these devices into something useful.
This process doesn't seem new to me, because it looks surprisingly like the one a French group has invented a few years back. (Do a search for Fievet, and Polyol process). I think Fievet even has some patents on the synthesis procedure.
There are actually many physical methods to make nanocrystals of inorganic materials: ball milling, synthesis in a cavitation field, spray pyrolysis. There are also many other (wet) chemical techniques, of which this is one: water/oil microemulsions, polymer solutions.
The problem with the physical methods is the particle agglomeration, as was indicated in the article. However, the chemical synthesis methods also have problems, since you're stuck with a templating agent that surrounds your nanocrystals. This may be hindering any practical use of the nanocrystals... But you can't burn off the templating agent, because then the particles will agglomerate again.
Actually, rolled or hammered steel will become stiffer, and more brittle compared to the cast metal weapons. That's not exactly the same as metal fatigue, which is induced by a repetitive bending (or torque) of the steel.
The cast metal-swords are thus a bit more flexible, but that's not a major problem. The big advantage is that it is less brittle, so the blade won't break as fast in battle.
Vaporware all the way. Why's that you ask? Well for starters there's no specs. Anywhere. Next: can you possibly imagine how much it costs to build such a thing?
The article at The Register states that the device will cost around 120,000 yen ($1100) in Japan. Quite a bit of $$$...
I don't know *anything* about GPS's, but as a corrolary to what someone said about hooking a GPS up to a Palm Pilot.. is there some kind of 'data out' port on a GPS that you could hook up to some kind of computerized device?
Then a website could be created that stores data on all available Geocaches, and you could run a program that checks your GPS data against that data and says: Nearest Geocache: 30 miles away or whatever. That'd be cool.
The GPS itself can do this. You could store the locations of Geocaches as waypoints in your GPS. The GPS will give you the location of the waypoints that are the closest to you.
Those websites listing Geocaches exist. Just follow the links in the original posting...
Slashdot Mirror
I'm not surprised that these folks didn't find anything, considering the sheer volume of images that's being transferred on the net each day.
Perhaps they were looking in all the wrong places to begin with. I would assume that if these terrorists use steganography to transmit messages, they would do so via a few selected channels. Perhaps they simply use e-mail to send the images, or some obscure binaries newsgroup.
They measure how often the toilet gets flushed, and for how long (I guess you can work out statistics on "difficult flushing jobs"
Maybe we should ask the friendly folks at Microsoft what happened to their nice UI experiment: Microsoft BOB
Not at all like that. As edremy already pointed out, those products are all accounted for in the combustion of fuel.
Incomplete combustion is nonsense: it doesn't form HF, as there is no hydrogen present in Teflon. Impure samples/contamination of oxygen supply: if this would be the case in any appreciable amount, then there still is no proper reaction path to form HF.
-CF2-CF2-CF2-CF2-...
Burning Teflon (i.e. reaction with O2) will give you all sorts of toxic fluorinated compounds, but I don't see how you get HF (hydrogen fluoride) out of this.
(1) NH3 + NaOCl = NaOH + NH2Cl
(2a) NH3 + NH2Cl + NaOH = N2H4 +NaCl + H2O
(2b) 2 NH2Cl + N2H4 = NH4Cl + N2
Reaction (2b) is a cometing reaction to (2a), and it is actually catalyzed by the formation of hydrazine (N2H4, not N2H2 as you stated). This means that only a small amount of hydrazine is formed.
The dangerous product in this case is NH2Cl, chloramine gas. This stuff is very bad for your mucous membranes, and can easily kill you when inhaled.
Hydrazine is dangerous stuff too, though. It is a strong reducing agent, is easily adsorbed through your skin, and it is carcinogenic. I work with this compound in the chemistrylab, and the label says that it's a threat to health and life at concentrations as low as 80 ppm.
Perhaps those pictures are classified information. DARPA is picking up the tab.
Considering that the author is a German, I wouldn't judge that too strongly.
Ritual burning of music? Agreed, there's a lot of crap music out there, but simply deleting the MP3s is a lot easier than setting them on fire...
For instance, the professor ranks all the students from high to low, and the top 10% gets an A. Not fair? Too bad, that's the way many professors do it.
Calm down now. There is not one single discipline that will solve all our world's problems (whether that's in medicine, energy, environment or whatnot). Any further advancements can only be made by inter disciplinary research. Biology and medicine have made great advances with the aid of other disciplines as well: chemistry, physics (e.g. microscopy), and yes engineering (e.g. combinatorial chemistry).
No, engineers by themselves will not find a way to eradicate HIV. But when you're talking about the state of modern biology, we're not exactly sure how to solve the problem. We know on what wall the dartboard is, but blindfolded it is difficult to hit. Nanomachines may not be the best approach, and medicine will probably find a solution before these machines are operational. That doesn't mean it is wasted research money, since there are plenty of alternative applications.
You're correct that we are still FAR away from any useful nanomachines-- if it ever proves feasible. We know how to drag along a few atoms over a surface under very controlled conditions, but we don't know how to make assemble functional 3-dimensional structures. Self-assembly is nice, but it will undoubtedly involve the construction of some very complex building blocks.
The major source of helium is natural gas fields. Natural gas contains about 2% helium.
While it is true that the US supplies 80% of the world's consumption, this is NOT because helium isn't found in other gas fields around the world. The U.S. can run their production plants cheaper than other countries. It still takes some effort to separate the helium from natural gas and other components (especially hydrogen). The U.S. is also one of the largest (if not THE largest) consumer of helium.
Helium COULD also be distilled from air (cryogenic distillation), but since there is only 0.0005% helium in air, this is too costly for now. However, it would be MUCH cheaper than getting it from the moon. I don't think cryogenic distillation from will ever be competitive with recovery from natural gas, but it's certainly a better alternative than getting it from the moon.
4 Al + 3 O2 -> 2 Al2O3 (+ heat)
Leave a cheap aluminum pan on the stove for too long, or heat up some aluminum foil, and it can burn, even though it's a metal.
There was a very big interest in putting Cadmium sulfide inside zeolites. But it's not all that simple to get the crystals in place, and plugging the holes with sulfur is a big problem. Also, IF this works, no one knows how to incorporate these devices into something useful.
This process doesn't seem new to me, because it looks surprisingly like the one a French group has invented a few years back. (Do a search for Fievet, and Polyol process). I think Fievet even has some patents on the synthesis procedure.
There are actually many physical methods to make nanocrystals of inorganic materials: ball milling, synthesis in a cavitation field, spray pyrolysis. There are also many other (wet) chemical techniques, of which this is one: water/oil microemulsions, polymer solutions.
The problem with the physical methods is the particle agglomeration, as was indicated in the article. However, the chemical synthesis methods also have problems, since you're stuck with a templating agent that surrounds your nanocrystals. This may be hindering any practical use of the nanocrystals... But you can't burn off the templating agent, because then the particles will agglomerate again.
The cast metal-swords are thus a bit more flexible, but that's not a major problem. The big advantage is that it is less brittle, so the blade won't break as fast in battle.
Check out the following link. It also has some images of their reconstructed sword blades: http://www.tms.org/pubs/journals/JOM/9809/Verhoeve n-9809.html
Please buy it from me; I've had my learning experience with it.
Yuck, scented goatse.cx spam...
Sounds a bit like the Apple Cube story. Maybe the storyboards were a little too close to the real thing...
Comes with floating rubber ducky antenna.
This is better
The vapor pressure of mercury is very low, so it should be ok under normal operation. However, I wonder what their scenario is in case of a fire.
Those websites listing Geocaches exist. Just follow the links in the original posting...