The temperature in caves (which are typically a few hundred feet deep) is close to the temperature of land, averaged over many years. In the northeast, caves are 50-55F, while in the southwest they are typically in the 60s and 70s. The part that Alexander was in is a very deep part of the cave; it's not a matter of "open air to the surface" that the temperature is that warm. It's simply how the cave is in southeastern New Mexico, where it gets frickin' hot in the summer, but never very cold in the winter.
From where he was, it's not possible that the cave served as a waveguide for the RF. And as best as I know, there's no metal in that part of the caves- electrical lines or metal handrails, as there are in the tourist parts of the cave- that would allow the transfer of RF energy.
Also note that because those computers are in an air-conditioned building (out here in the desert), that waste energy needs to be dumped out of the building for much of the year, costing additional bucks. It's a small but (over ten years) significant load on the HVAC system, ultimately paid for by taxpayers.
Years ago, I went back to academia after a few years in industry. At the time, we had a post-doc working on vaccines; a salesperson from one of the big vendors had walked in, and I was shooting the breeze with them when the post-doc left the room. I noticed she had left a brand-new container of an exotic toxin that she just received from Sigma on her desk- right next to her coffee.
"Do they do this in industry?" I asked the vendor. Seriously- if it had been a "working" environment instead of academic, that would have been a firing. Instead, that's just how it goes in academia.
That would also depend upon the time of the year that the study was done; I am not familiar with the one that you cite, but presumably it was done at some point where maintenance was required. Many of these windpower facilities are in areas that geographically "funnel" the wind; these areas also happen to overlap with the routes for migratory birds. Kills may peak at certain times of the year.
Moreover, ground-based sampling in windpower sites is not straightforward; scavengers can pick up carcasses within minutes or hours. Given the magnitude of some of these sites, it's difficult to base mortality studies on carcass counts alone. Moreover, sites associated with increased bird mortality would accumulate higher numbers of scavengers, making accurate counts even more difficult. Admittedly, it's been a number of years since I did research in the field, but it was pretty much a joke- some guy would wheel around on an ATV over several acres and look for dead birds once every day or so. Too much territory, too much grass and rock, too many coyotes and feral dogs. There's no way anyone could expect a realistic count. The majority of the migratory flights were at night; we were using radar to track them. If a bird is killed in the middle of the night, the coyotes would take off with it and it would never be counted because nobody would see it at night.
Fortunately, open-ocean sites don't have the geographic effects that terrestrial sites do, which should- in theory- reduce the number of bird kills.
Also note that, yes- domestic cats do impact songbird populations, as do structures and windows. But there's this pesky little Migratory Bird Treaty Act of 1918 that prevents the killing of migratory birds- hence the concern about incidental "take" from windpower sites. This includes concern about larger species such as geese, hawks, and eagles that are affected less by feral and domestic cats. So- greater potential for impact by windpower, less from cats.
I used to work as an explosives chemist- including once at one of the favorite facilities for Mythbusters- so maybe I can make a constructive comment or two.
Ammonium nitrate (AN) is used for stumping fields for a lot of reasons. First off, it's cheap. ANFO is just about as cheap as you can get in terms of "bang for your buck." When you're dropping iron bombs, cost isn't so much of a concern- even moreso with torpedos- so more expensive stuff is used for these applications.
Secondly, it's highly insensitive; ANFO either needs to be sensitized with other compounds (aluminum flake, for example), or a large booster has to be used in the firing train for it to be reliably detonated. Even then, most of the large shots I've been involved with used two independent firing trains, making a fizzle much less likely.
Thirdly, ANFO for stumping fields uses readily available components- a sack of AN (which, I note, can still be purchased locally- for now- with no special paperwork), and any one of a number of hydrocarbons like diesel.
However, ANFO has a particular property that makes it amenable to stumping, which is that it provides less brisance- more "heave," and less "shatter." If you're moving rock, it's undesirable to move just a few hundred pounds that have been reduced to powder; normally you want to move a few thousand pounds that have been reduced to cobbles. It's the difference between being punched in the shoulder, and being shoved; given the same amount of energy, the effects will be dramatically different.
AN *can* be combined with other fuels to provide much greater brisance- anhydrous hydrazine comes to mind, but that's dangerous stuff even by the high standards held for explosives. Moreover, it's toxic and hard to store.
As an aside, it is disappointing to see Mythbusters using the "big shot in an open field" technique. They have a bigger budget, and should have gone somewhere that specializes in that sort of thing, like they have in the past. This obviously wasn't the right venue for a quarter ton ANFO shot. Noise abatement is a big part of dealing with energetic materials, and whomever they had on the job to make that assessment screwed up pretty badly.
Well, so is tellurium. Individuals exposed to tellurium even at very low concentrations develop "tellurium breath," a foul garlic-like odor. As an undergrad in chemistry in college, I was informed only half-jokingly by a professor that was an occupational hazard that had restricted our knowledge of the element.
However, from a production standpoint its scarcity is troubling; Wikipedia states its presence is lower in the crust than that of platinum, making it the rarest stable element by concentration. 500 tons of copper ore- apparently a decent source of the stuff- leads to the production of about one pound of tellurium. Perhaps that's one reason why First Solar settled here in copper country- Arizona.
I can't seem to find how much Te is used to dope Cd to produce CdTe; even if it's not a lot (part-per-million concentrations), they will run into problems quickly, so I'd be interested in finding out how they plan on working around that.
Personally, I wouldn't worry too much about toxicity, so long as the stuff is confined within panels. It's insoluble (can't seem to find at what level- surely some minute amount dissolves in water), but it seems to be safe enough once confined within panels. Presumably the designers worry enough about hail damage that the panels are reasonably well-constructed to prevent release of material.
My 1995 Saturn SL1 gets 40 MPG (overall- probably 43-44 on the highway) in the winter (less in the summer when I need to run the a/c, of course). That's a full-size sedan that seats 5, and can fit almost two bodies in the trunk.
The first engine and clutch (on a manual- my first manual transmission) lasted 231,400 miles, and the first time it stranded me for anything other than a dead battery was at that point. Drop in a used engine, and it's back on the road- getting 40 MPG while meeting the county's stringent air quality laws by nearly half.
What the heck, Detroit? What did you do to our cars? (I know- gave them decent acceleration and class, but- dangit, I like my Saturn. Even if everybody else laughs at me, it's saved me a lot of money and hassles over the years.)
Just a stab in the dark, as I don't really have any special insight here. But it would seem likely the concept is to breed large quantities of GMO'd mosquitoes in the lab (providing them with the antibiotic throughout their life cycle), and then release them into the wild. They would then mate with wild-type skeeters, producing offspring with the gene. When those offspring fail to reach maturity because of the absence of tetracycline, it reduces the number of mosquitoes in the wild.
This is not exactly a new concept, although the implementation is quite different. Cattle screw worm (which was a serious economic pest) has been eliminated from North and South America from an aggressive irradiation program in which larvae are reared in large numbers, and then irradiated with cobalt-60. Insert your own "huge, radioactive flies" joke here, but the net upshot is that the irradiated flies mated with irradiated flies and failed to produce fertile offspring for whatever reason. Fewer fertile offspring is a good thing when it comes to population control of undesirable cattle parasites.
Similar programs with Mediterranean fruit flies have been used to control or eradicate populations, but there were some issues a few years back with making sure they really were sterilized by the procedure.
So, it's nothing *that* new, and variations on the technique have proven useful in the past. Now instead of green, glow-in-the-dark flies, we'll just have mutant, GMO'd mosquitoes. Life goes on- hopefully without dengue. Maybe someday without malaria.
Tobias (who either *is* security.org or works for them) is the author of Locks, Safes, and Security: An International Police Reference. On their webpage they announce a detailed look at the Medeco M3.
From the description, it sounds like they have a way to bypass it, but no idea if it's true or not when they won't release details. I think these are the same guys that also manufacture the tools specific to bypassing Abloys.
I'm wondering if the techniques they are using are "improved" over the old techniques- which, as of 1 September, 2005, has been declared unreliable by the FBI. The whole technique has been declared "flawed."
For years, comparative bullet lead analyses were considered accurate and good proof; I remember reading the neutron activation analyses when I was in college as an undergrad, and thinking it was a fantastic technique. But now it looks like 40 years' worth of convictions are at risk- 2,500 analyses, with 20% of these being introduced as evidence at trial.
With high-security systems, the blanks are under patent. Only locksmiths who service those locks have access to them. With most systems, you end up with regional distributors, and if you walk in asking to get a copy made, they'll recognize it as one of theirs and confiscate it- and inform the true owner of what happened. I've actually seen that happen- it's pretty unfortunate for the guy working for a major bank to lose his job over that sort of thing. They can then mike the key and determine whose it is; if it is stamped with a serial number, it's even easier.
All bets are off if a machinist is available to duplicate it. This is made very difficult with sidebar locks such as ASSA, or with odd keys such as Abloy. A machinist would also have to duplicate the wards and angle cuts if duplicating Medeco keys.
So while the possibility is there, I have yet to hear of it happening.
With some high security systems (Medeco, Assa, etc.), it could be written into the contract that unless all keys were returned at the time of departure from the company (or upon request by a supervisor), it was possible to withhold a deposit or the last paycheck of a departing employee to defray the expenses of re-keying the locks.
This was from a long time ago, when I worked as a locksmith. I have no idea if it's still legal to do so.
I worked my way through college as a locksmith. I've always favored hardware security (keys) over electronic widgetry. Talking to a Medeco dealer about getting your locks on a solid masterkey system would give you a solid system, but allowing remote sites to be accessed- possibly by different agents each time- wouldn't work.
One solution might be Videx. I've only glossed over their literature, but they seem to have a pretty good solution in place.
Specifically, the section on how "the CyberKey Authorizer enhances CyberLock systems by providing the ability to program and download CyberKeys at remote locations." That might be too pricey for your application. I've never priced out "door" costs on Videx hardware.
Halons work to extinguish fire using several mechanisms. Oxygen displacement- not absorption or binding- is one of them, but if this were the only factor, then dry nitrogen, carbon dioxide, or other inert gas would work just as well.
There are four things required for combustion: oxidizer, fuel, heat, and a chemical reaction that is self-sustaining- the "chain reaction," in which free radicals are formed. Halons work by kicking off chlorine, bromine, or fluorine radicals in the heat of the fire, ending these reactions. Unfortunately, the same properties that make this class of compounds so wonderful for extinguishing fires is also what makes them so good at terminating the production of ozone.
I also seem to recall something in my distant past as a fire instructor that halons as a group have a fairly high specific heat, meaning they carry away more heat from the fire; this is a relatively minor factor when compared to things like water which have high specific heat and very high heat of vaporization. Water is surprisingly good at putting out electrical fires; energized systems can be handled by using distilled water, as was done at Browns Ferry nuclear power plant in Tennessee in 1975. But it's messy and doesn't fight "three dimensional" fires very well.
Replacements such as FM-200 and Novec 1230 that do not survive long enough to reach the stratosphere have been made and are now available. They are comparable in effectiveness to more traditional halons (Halon 1211 and 1301), and Novec is shipped as a liquid rather than a compressed gas. This makes it safer and less expensive to transport. Being fluorinated molecules (no chlorine, just fluorine) less phosgene is produced during a fire, which is a good thing.
We'll know for sure very soon, one way or another. Thimerosal has disappeared from the (minority) of vaccines that had them in the first place.
Table of mercury in childhood vaccines
So- of those few vaccines that still contain thimerosal, such as Fluzone (the most I can find in the tables, at 25 micrograms mercury for a 0.5 mL injection), how does that compare with what you eat?
You get twice that much by ingestion from a single gram of chunk white tuna. Or, from the Mercury Calculator, two ounces of canned albacore is 180% of what a 40-pound child should eat in a day.
Of course, injection is very different from ingestion- but the example I give is extreme. After the influenza vaccines, thimerosal levels drop off dramatically- and virtually all use of thimerosal was discontinued years ago.
So stop whining about vaccinating your kids. There are low- and no-thimerosal options for everything but straight TT (tetanus toxin), and you can get your kid stuck for tetanus without thimerosal by using Tdap or another vaccine with a tetanus component.
And in another 5 years or so, we'll know for sure if the thimerosal was responsible. Until then, your kids get way more exposure from food, water, and air than vaccines.
The videos were from Brainiac, and if you look carefully in the slow motion of the first bathtub they blow up, you can see the wire that leads over the size to the charge they set off. I've worked with cesium and rubidium, and they're not too much stronger than potassium- not enough that such a small amount would blow it up, anyway. Simply put, they fudged it with a small charge to wow the audience. Some great science going on there.
As for the "new terrorist binary explosive" video, that's simply a small demo charge in the post used to support the melon. The shower of sparks pretty much gives it away. No tiny amount of chemical exposives can cause that much damage. Moreover, if it were that strong, the author whipped up a massive batch of the stuff (in relative terms)- an explosive sufficiently sensitive to shock initiation that mixing it the wrong way would have killed him, when he could have made a much smaller batch. It's just silliness. It also seems the sky is a bit darker after the "explosion," as if the melon were removed and a small pyro charge was set off and spliced in there. The quantity of explosives used is far too small, even for the most powerful of primary explosives.
Disclaimer: I am, in fact, an explosives chemist with extensive experience with primary, secondary, and blasting explosives, including terrorist "improvised" explosives and devices.
Things can get tricky here. It can be a bit like sculpture, in a way- if you chisel your evidence just the right way, maybe it'll look like what you want. That can be a very bad thing. However, some investigations require tailor-made tests; I can think of a couple instances- none of which had anything to do with trying the accused, fortunately- that I was called upon to create a test or an experiment that produced results that could be used to determine an association. For example, when the accused was found with certain components, I was asked to determine if those components could be used to detonate a certain kind of bomb. They weren't used in the trial, but they were used to hold the suspect in pre-9/11 America when you had to prove that sort of thing.
Some tests rely upon the odds of producing a match- as with fingerprints. However, these are not always reliable. That's biometrics, with a long and sometimes dubious track record. I'm not even sure if there's been a paper in the refereed literature that cites the statistics on the likelihood of a match between two non-related prints given a certain number of features.
Other fields, such as firearms and toolmarks, are even more open to interpretation. DNA evidence is a little better in some regards, but these figures have been botched, too- sometimes with lab accidents, sometimes intentionally. Fortunately, standards have gotten a lot tighter, and DNA evidence has been used to exonerate a considerable number of the accused, including a distressing number of individuals on death row.
Fortunately, some are straightforward. While that field test for, say, cocaine might give a false positive for several hundred (or thousand) compounds, the Raman infrared spectrometer can tell you what it is, even through the polyethylene bag in which the sample is kept. Then another test- gas chromatography or gas chrom with a mass spec detector (GC/MS) is used to confirm. The chemistry side of it is pretty good, provided orthogonal analysis- two independent tests based on different principles of analysis- can demonstrate that the sample has been identified correctly.
What is probably the single most annoying thing about fire investigation- from the investigator's perspective- is that arson is a terribly difficult crime to prove. Without a witness or some form of photographic or video evidence where an individual physically lights something on fire, the crime of arson is difficult to prove. As an instructor long ago put it to us: A man walks into a structure, and then walks back out. Later, it catches on fire. Houses burn all the time- bad wiring, gasoline stored near a gas water heater, cigarettes left burning. But causality- that that fire was intentionally set, and was set by that individual- may be difficult to prove.
In that regard, arson can be more difficult to prove than murder. With murder, there is frequently trace evidence with everything from blood droplets to weapons used, that can associate the murderer with the crime. With arson, in many cases there is heavy fire, smoke, and water damage, as well as the difficulty in proving that a fire started intentionally versus accidentally. Trace evidence such as gasoline found on the shoes of the accused arsonist can often be explained by more mundane events, such as spills at a filling station.
Making things worse, the folks who investigate are often poorly- or incorrectly- trained, and sometimes don't even want the job. Things are changing and candidates are frequently better educated than they have been in the past, but it's still a little rough around the edges. There aren't too many investigators in the field with advanced degrees, and a week or two of schooling (Arson I and II) at a state fire academy or the National Fire Academy are considered enough to get to work in many cases. 40 hours of fire investigation training, and you can help in putting people behind bars for what is considered a heinous crime such as arson of a habitable structure.
Sometimes investigation doesn't even start with the fire itself. Financial records are often scrutinized to determine if the accused would benefit financially. Business not doing well? Maybe it was torched. Home being remodeled? Maybe a convenient excuse to collect on insurance because of some major construction issues that existed. Upside down in your auto loan and gas hit $3 a gallon? That Yukon sure burns good!
Put all these together, and it's little wonder that some of the folks accused and convicted of this sort of thing are convicted and jailed. Many are poor, and get lousy lawyers- juries are likely to convict on scant evidence when the alternative is to let a possible firebug out on the streets.
Fortunately, there are improvements, and the standards for training have gone way the heck up in past years. Certification under some standard for training is often required for the job, as well as continuing education to stay on the job. Engineers, chemists, modelers, and physicists tackle some of the more difficult issues with lab tests to back up what's being said in court. It's one thing to say that a steam pipe at X degrees for Y years can eventually cause enough pyrolysis of nearby wood to create open flame; it's another to have some PhD back it up with experiments that prove it, possibly exonerating the accused.
Sometimes folks believe strange things from way the heck back in their training. This is part of the legend behind "spontaneous human combustion." The '921 says in it somewhere in a straightforward (and vaguely comforting) manner that humans do not spontaneously combust. Now only if we can do that with the other bits of legend that investigators have clung to over the ages.
I broke the scaphoid bone in my right hand, a little cashew-sized thing that is easy to break. ER visit was $700 (covered by insurance) for one X-ray on a machine in a room with a cracked window for the operator to look through. Went to a hand specialist at the Mayo Clinic who immediately took new films on a digital machine- they were sent upstairs by wire, no hard copy ever made, and the resolution was much better. The first X-rays were awful in comparison. Still broken, so I had a composite cast put on, which went all the way up to mid-bicep (for a bone in my wrist!). After two weeks, new cast- this one up to mid-forearm. I think I went through three casts total, with X-rays after each was taken off. Total cost- from the Mayo- $1900.
Insurance wouldn't pay for it, as the Mayo isn't a preferred provider. They gave me the one-time-only $500 payout for this sort of thing; I paid $1400 out of pocket. The first bill arrived 14 MONTHS after my last cast was taken off; Arizona requires bills must be received by customers within 30 days, or something like that. I could have weasled out of it because of the billing delays, but- hey, I got what I paid for, so I coughed up the money since my hand works great. Had to drive a stick shift in Phoenix traffic like that for a month and a half, but it was a lot better than getting the bone screwed back together- invasive surgery.
Calcium bromide (CaBr2) is slightly more hygroscopic, absorbing moisture down to 16% RH (Handbook of Chemistry and Physics); it's also a hexahydrate- it sponges up a lot of moisture. Right below that is lithium chloride, which continues to absorb down to 11% RH.
Most likely it's a system where prilled or powdered salt is tumbled through dry air to absorb moisture; it's then roasted to release the moisture, captured under reduced pressure to reduce the amount of energy required, and returned to its anhydrous state. It'll be clumpy and chunky, so it'll have to be re-ground into a fine powder before reuse.
The $.30 a gallon is probably largely from the amount required in the removal of the water from the hydrate; distillation of water runs ~$.25 a gallon (assuming no recycling of the waste heat from condensation to pre-heat water going into the boiler) at $.10/kwh. Using gasoline or diesel would be considerably more expensive- thus the reduced pressure.
Distilled water from air- not too shabby. I've thought about trying the same here in the desert (where it's routinely ~10% RH in Phoenix), but it's just not worth it.
As a locksmith (trained- not currently practicing), I gotta comment on locks that will resist this type of attack. The Corbin Emhart (System 70) really was very good, but not good enough to keep up with things; like other clever, creative systems, it went away because not enough people used it.
A number of systems will resist this type of attack. Probably the best is the Abloy, which I understand was bought out along with ASSA by Medeco. Alboy relies upon a sidebar; the discs need to be aligned, a sidebar drops into place, and the lock opens. I also understand there is a way to bypass this system, although the tools are pricey, resticted, and since Abloy locks are relatively rare in the United States, they remain relatively secure.
ASSA also relies upon a sidebar, with the code being cut into the side of the blank. The blanks are heavily restricted, and locksmiths have to account for all of them- even ones that are mis-cut. Of course, a sidebar can be regional, which is its biggest flaw; apparently they are more popular in Europe. If a local locksmith uses a given key profile, then it is simple enough to turn a given cut key into a "bump" key.
It would seem- although I have not tested it- that Medeco locks are immune; they require that the pins be brought to the correct height and that they be rotated (left, center, right- only three possible combinations) before the lock will open. Last I checked, it was still much easier to grind a Medeco out of existance than it was to pick it; they *can* be picked, but it takes many hours. I never liked Medeco, but since Abloy and other types of locks that offer higher security than hardware-store junk were either insanely expensive or no longer available, as their keys tend to be brittle and break right at the bow. But that's what I installed on the house; each door cost me $160 for a single-cylinder lock, but at least I know the lock is secure. Entry would have to be made in some other way than bumping or picking; further, high end locks also offer crush-resistant collars (to avoid "pipe wrench" attacks), better bolts (to prevent icepick and cutting attacks), and so forth. They just *weigh* more- it's not pot metal and good intentions in every box, unlike some makes.
True story: in the early 1990's, some genius figured out that every high-security door lock on the market could be attacked in seconds- sometimes faster than using the key- with an ice pick or a bit of wire or welding rod. Pierce the door in the right way that the tool can be used to push back part of the bolt, and you're in. Ice pick attacks were popularized, but the wave of thefts never manifested. Newer generations of bolts were issued that prevent this type of attack.
"Bumping" presents a somewhat higher threat level given that it works on more commonly available locks, which are used on probably 95-99% of homes in the United States. Given that a "Kwikset" can be bypassed with a sheet metal screw, a screwdriver, and a pair of "Vice Grips," it's a wonder more homes don't succumb to this sort of stuff every day. Fortunately (?), thieves rarely look at a home the same way we do; a good burglar or a drug addict desperate for a $20 fix will use whatever tools and techniques are handy, at great expense to society. Given that these individuals might be able to sell their gains for perhaps 10% of their value, the amount that either has to steal and re-sell to get by is quite remarkable. They don't pick locks, and they probably won't use "bump" keys.
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Being a rescue trog myself, the running joke is that "spelunk" is the noise you make hitting the ground when you rappel off the end of your rope.
The temperature in caves (which are typically a few hundred feet deep) is close to the temperature of land, averaged over many years. In the northeast, caves are 50-55F, while in the southwest they are typically in the 60s and 70s. The part that Alexander was in is a very deep part of the cave; it's not a matter of "open air to the surface" that the temperature is that warm. It's simply how the cave is in southeastern New Mexico, where it gets frickin' hot in the summer, but never very cold in the winter.
From where he was, it's not possible that the cave served as a waveguide for the RF. And as best as I know, there's no metal in that part of the caves- electrical lines or metal handrails, as there are in the tourist parts of the cave- that would allow the transfer of RF energy.
Also note that because those computers are in an air-conditioned building (out here in the desert), that waste energy needs to be dumped out of the building for much of the year, costing additional bucks. It's a small but (over ten years) significant load on the HVAC system, ultimately paid for by taxpayers.
Years ago, I went back to academia after a few years in industry. At the time, we had a post-doc working on vaccines; a salesperson from one of the big vendors had walked in, and I was shooting the breeze with them when the post-doc left the room. I noticed she had left a brand-new container of an exotic toxin that she just received from Sigma on her desk- right next to her coffee.
"Do they do this in industry?" I asked the vendor. Seriously- if it had been a "working" environment instead of academic, that would have been a firing. Instead, that's just how it goes in academia.
That would also depend upon the time of the year that the study was done; I am not familiar with the one that you cite, but presumably it was done at some point where maintenance was required. Many of these windpower facilities are in areas that geographically "funnel" the wind; these areas also happen to overlap with the routes for migratory birds. Kills may peak at certain times of the year.
Moreover, ground-based sampling in windpower sites is not straightforward; scavengers can pick up carcasses within minutes or hours. Given the magnitude of some of these sites, it's difficult to base mortality studies on carcass counts alone. Moreover, sites associated with increased bird mortality would accumulate higher numbers of scavengers, making accurate counts even more difficult. Admittedly, it's been a number of years since I did research in the field, but it was pretty much a joke- some guy would wheel around on an ATV over several acres and look for dead birds once every day or so. Too much territory, too much grass and rock, too many coyotes and feral dogs. There's no way anyone could expect a realistic count. The majority of the migratory flights were at night; we were using radar to track them. If a bird is killed in the middle of the night, the coyotes would take off with it and it would never be counted because nobody would see it at night.
Fortunately, open-ocean sites don't have the geographic effects that terrestrial sites do, which should- in theory- reduce the number of bird kills.
Also note that, yes- domestic cats do impact songbird populations, as do structures and windows. But there's this pesky little Migratory Bird Treaty Act of 1918 that prevents the killing of migratory birds- hence the concern about incidental "take" from windpower sites. This includes concern about larger species such as geese, hawks, and eagles that are affected less by feral and domestic cats. So- greater potential for impact by windpower, less from cats.
I used to work as an explosives chemist- including once at one of the favorite facilities for Mythbusters- so maybe I can make a constructive comment or two.
Ammonium nitrate (AN) is used for stumping fields for a lot of reasons. First off, it's cheap. ANFO is just about as cheap as you can get in terms of "bang for your buck." When you're dropping iron bombs, cost isn't so much of a concern- even moreso with torpedos- so more expensive stuff is used for these applications.
Secondly, it's highly insensitive; ANFO either needs to be sensitized with other compounds (aluminum flake, for example), or a large booster has to be used in the firing train for it to be reliably detonated. Even then, most of the large shots I've been involved with used two independent firing trains, making a fizzle much less likely.
Thirdly, ANFO for stumping fields uses readily available components- a sack of AN (which, I note, can still be purchased locally- for now- with no special paperwork), and any one of a number of hydrocarbons like diesel. However, ANFO has a particular property that makes it amenable to stumping, which is that it provides less brisance- more "heave," and less "shatter." If you're moving rock, it's undesirable to move just a few hundred pounds that have been reduced to powder; normally you want to move a few thousand pounds that have been reduced to cobbles. It's the difference between being punched in the shoulder, and being shoved; given the same amount of energy, the effects will be dramatically different.
AN *can* be combined with other fuels to provide much greater brisance- anhydrous hydrazine comes to mind, but that's dangerous stuff even by the high standards held for explosives. Moreover, it's toxic and hard to store.
As an aside, it is disappointing to see Mythbusters using the "big shot in an open field" technique. They have a bigger budget, and should have gone somewhere that specializes in that sort of thing, like they have in the past. This obviously wasn't the right venue for a quarter ton ANFO shot. Noise abatement is a big part of dealing with energetic materials, and whomever they had on the job to make that assessment screwed up pretty badly.
Well, so is tellurium. Individuals exposed to tellurium even at very low concentrations develop "tellurium breath," a foul garlic-like odor. As an undergrad in chemistry in college, I was informed only half-jokingly by a professor that was an occupational hazard that had restricted our knowledge of the element.
However, from a production standpoint its scarcity is troubling; Wikipedia states its presence is lower in the crust than that of platinum, making it the rarest stable element by concentration. 500 tons of copper ore- apparently a decent source of the stuff- leads to the production of about one pound of tellurium. Perhaps that's one reason why First Solar settled here in copper country- Arizona.
I can't seem to find how much Te is used to dope Cd to produce CdTe; even if it's not a lot (part-per-million concentrations), they will run into problems quickly, so I'd be interested in finding out how they plan on working around that.
Personally, I wouldn't worry too much about toxicity, so long as the stuff is confined within panels. It's insoluble (can't seem to find at what level- surely some minute amount dissolves in water), but it seems to be safe enough once confined within panels. Presumably the designers worry enough about hail damage that the panels are reasonably well-constructed to prevent release of material.
My 1995 Saturn SL1 gets 40 MPG (overall- probably 43-44 on the highway) in the winter (less in the summer when I need to run the a/c, of course). That's a full-size sedan that seats 5, and can fit almost two bodies in the trunk.
The first engine and clutch (on a manual- my first manual transmission) lasted 231,400 miles, and the first time it stranded me for anything other than a dead battery was at that point. Drop in a used engine, and it's back on the road- getting 40 MPG while meeting the county's stringent air quality laws by nearly half.
What the heck, Detroit? What did you do to our cars? (I know- gave them decent acceleration and class, but- dangit, I like my Saturn. Even if everybody else laughs at me, it's saved me a lot of money and hassles over the years.)
This is not exactly a new concept, although the implementation is quite different. Cattle screw worm (which was a serious economic pest) has been eliminated from North and South America from an aggressive irradiation program in which larvae are reared in large numbers, and then irradiated with cobalt-60. Insert your own "huge, radioactive flies" joke here, but the net upshot is that the irradiated flies mated with irradiated flies and failed to produce fertile offspring for whatever reason. Fewer fertile offspring is a good thing when it comes to population control of undesirable cattle parasites.
Similar programs with Mediterranean fruit flies have been used to control or eradicate populations, but there were some issues a few years back with making sure they really were sterilized by the procedure.
So, it's nothing *that* new, and variations on the technique have proven useful in the past. Now instead of green, glow-in-the-dark flies, we'll just have mutant, GMO'd mosquitoes. Life goes on- hopefully without dengue. Maybe someday without malaria.
"Air Combat Command"
Click on "CONUS Crash Locator." It's not complete, but it's pretty good.
Tobias (who either *is* security.org or works for them) is the author of Locks, Safes, and Security: An International Police Reference. On their webpage they announce a detailed look at the Medeco M3. From the description, it sounds like they have a way to bypass it, but no idea if it's true or not when they won't release details. I think these are the same guys that also manufacture the tools specific to bypassing Abloys.
I'm wondering if the techniques they are using are "improved" over the old techniques- which, as of 1 September, 2005, has been declared unreliable by the FBI. The whole technique has been declared "flawed."
For years, comparative bullet lead analyses were considered accurate and good proof; I remember reading the neutron activation analyses when I was in college as an undergrad, and thinking it was a fantastic technique. But now it looks like 40 years' worth of convictions are at risk- 2,500 analyses, with 20% of these being introduced as evidence at trial.
With high-security systems, the blanks are under patent. Only locksmiths who service those locks have access to them. With most systems, you end up with regional distributors, and if you walk in asking to get a copy made, they'll recognize it as one of theirs and confiscate it- and inform the true owner of what happened. I've actually seen that happen- it's pretty unfortunate for the guy working for a major bank to lose his job over that sort of thing. They can then mike the key and determine whose it is; if it is stamped with a serial number, it's even easier.
All bets are off if a machinist is available to duplicate it. This is made very difficult with sidebar locks such as ASSA, or with odd keys such as Abloy. A machinist would also have to duplicate the wards and angle cuts if duplicating Medeco keys.
So while the possibility is there, I have yet to hear of it happening.
With some high security systems (Medeco, Assa, etc.), it could be written into the contract that unless all keys were returned at the time of departure from the company (or upon request by a supervisor), it was possible to withhold a deposit or the last paycheck of a departing employee to defray the expenses of re-keying the locks.
This was from a long time ago, when I worked as a locksmith. I have no idea if it's still legal to do so.
I worked my way through college as a locksmith. I've always favored hardware security (keys) over electronic widgetry. Talking to a Medeco dealer about getting your locks on a solid masterkey system would give you a solid system, but allowing remote sites to be accessed- possibly by different agents each time- wouldn't work.
One solution might be Videx. I've only glossed over their literature, but they seem to have a pretty good solution in place.
http://www.videx.com/products/detail/cyberlock.h tml
Specifically, the section on how "the CyberKey Authorizer enhances CyberLock systems by providing the ability to program and download CyberKeys at remote locations." That might be too pricey for your application. I've never priced out "door" costs on Videx hardware.
Halons work to extinguish fire using several mechanisms. Oxygen displacement- not absorption or binding- is one of them, but if this were the only factor, then dry nitrogen, carbon dioxide, or other inert gas would work just as well.
There are four things required for combustion: oxidizer, fuel, heat, and a chemical reaction that is self-sustaining- the "chain reaction," in which free radicals are formed. Halons work by kicking off chlorine, bromine, or fluorine radicals in the heat of the fire, ending these reactions. Unfortunately, the same properties that make this class of compounds so wonderful for extinguishing fires is also what makes them so good at terminating the production of ozone.
I also seem to recall something in my distant past as a fire instructor that halons as a group have a fairly high specific heat, meaning they carry away more heat from the fire; this is a relatively minor factor when compared to things like water which have high specific heat and very high heat of vaporization. Water is surprisingly good at putting out electrical fires; energized systems can be handled by using distilled water, as was done at Browns Ferry nuclear power plant in Tennessee in 1975. But it's messy and doesn't fight "three dimensional" fires very well.
Replacements such as FM-200 and Novec 1230 that do not survive long enough to reach the stratosphere have been made and are now available. They are comparable in effectiveness to more traditional halons (Halon 1211 and 1301), and Novec is shipped as a liquid rather than a compressed gas. This makes it safer and less expensive to transport. Being fluorinated molecules (no chlorine, just fluorine) less phosgene is produced during a fire, which is a good thing.
So- of those few vaccines that still contain thimerosal, such as Fluzone (the most I can find in the tables, at 25 micrograms mercury for a 0.5 mL injection), how does that compare with what you eat?
You get twice that much by ingestion from a single gram of chunk white tuna. Or, from the Mercury Calculator, two ounces of canned albacore is 180% of what a 40-pound child should eat in a day.
Of course, injection is very different from ingestion- but the example I give is extreme. After the influenza vaccines, thimerosal levels drop off dramatically- and virtually all use of thimerosal was discontinued years ago.
So stop whining about vaccinating your kids. There are low- and no-thimerosal options for everything but straight TT (tetanus toxin), and you can get your kid stuck for tetanus without thimerosal by using Tdap or another vaccine with a tetanus component. And in another 5 years or so, we'll know for sure if the thimerosal was responsible. Until then, your kids get way more exposure from food, water, and air than vaccines.
So you're not a lawyer?
Please. I still have some self-respect.
The videos were from Brainiac, and if you look carefully in the slow motion of the first bathtub they blow up, you can see the wire that leads over the size to the charge they set off. I've worked with cesium and rubidium, and they're not too much stronger than potassium- not enough that such a small amount would blow it up, anyway. Simply put, they fudged it with a small charge to wow the audience. Some great science going on there.
As for the "new terrorist binary explosive" video, that's simply a small demo charge in the post used to support the melon. The shower of sparks pretty much gives it away. No tiny amount of chemical exposives can cause that much damage. Moreover, if it were that strong, the author whipped up a massive batch of the stuff (in relative terms)- an explosive sufficiently sensitive to shock initiation that mixing it the wrong way would have killed him, when he could have made a much smaller batch. It's just silliness. It also seems the sky is a bit darker after the "explosion," as if the melon were removed and a small pyro charge was set off and spliced in there. The quantity of explosives used is far too small, even for the most powerful of primary explosives.
Disclaimer: I am, in fact, an explosives chemist with extensive experience with primary, secondary, and blasting explosives, including terrorist "improvised" explosives and devices.
Things can get tricky here. It can be a bit like sculpture, in a way- if you chisel your evidence just the right way, maybe it'll look like what you want. That can be a very bad thing. However, some investigations require tailor-made tests; I can think of a couple instances- none of which had anything to do with trying the accused, fortunately- that I was called upon to create a test or an experiment that produced results that could be used to determine an association. For example, when the accused was found with certain components, I was asked to determine if those components could be used to detonate a certain kind of bomb. They weren't used in the trial, but they were used to hold the suspect in pre-9/11 America when you had to prove that sort of thing.
Some tests rely upon the odds of producing a match- as with fingerprints. However, these are not always reliable. That's biometrics, with a long and sometimes dubious track record. I'm not even sure if there's been a paper in the refereed literature that cites the statistics on the likelihood of a match between two non-related prints given a certain number of features.
Other fields, such as firearms and toolmarks, are even more open to interpretation. DNA evidence is a little better in some regards, but these figures have been botched, too- sometimes with lab accidents, sometimes intentionally. Fortunately, standards have gotten a lot tighter, and DNA evidence has been used to exonerate a considerable number of the accused, including a distressing number of individuals on death row.
Fortunately, some are straightforward. While that field test for, say, cocaine might give a false positive for several hundred (or thousand) compounds, the Raman infrared spectrometer can tell you what it is, even through the polyethylene bag in which the sample is kept. Then another test- gas chromatography or gas chrom with a mass spec detector (GC/MS) is used to confirm. The chemistry side of it is pretty good, provided orthogonal analysis- two independent tests based on different principles of analysis- can demonstrate that the sample has been identified correctly.
What is probably the single most annoying thing about fire investigation- from the investigator's perspective- is that arson is a terribly difficult crime to prove. Without a witness or some form of photographic or video evidence where an individual physically lights something on fire, the crime of arson is difficult to prove. As an instructor long ago put it to us: A man walks into a structure, and then walks back out. Later, it catches on fire. Houses burn all the time- bad wiring, gasoline stored near a gas water heater, cigarettes left burning. But causality- that that fire was intentionally set, and was set by that individual- may be difficult to prove.
In that regard, arson can be more difficult to prove than murder. With murder, there is frequently trace evidence with everything from blood droplets to weapons used, that can associate the murderer with the crime. With arson, in many cases there is heavy fire, smoke, and water damage, as well as the difficulty in proving that a fire started intentionally versus accidentally. Trace evidence such as gasoline found on the shoes of the accused arsonist can often be explained by more mundane events, such as spills at a filling station.
Making things worse, the folks who investigate are often poorly- or incorrectly- trained, and sometimes don't even want the job. Things are changing and candidates are frequently better educated than they have been in the past, but it's still a little rough around the edges. There aren't too many investigators in the field with advanced degrees, and a week or two of schooling (Arson I and II) at a state fire academy or the National Fire Academy are considered enough to get to work in many cases. 40 hours of fire investigation training, and you can help in putting people behind bars for what is considered a heinous crime such as arson of a habitable structure.
Sometimes investigation doesn't even start with the fire itself. Financial records are often scrutinized to determine if the accused would benefit financially. Business not doing well? Maybe it was torched. Home being remodeled? Maybe a convenient excuse to collect on insurance because of some major construction issues that existed. Upside down in your auto loan and gas hit $3 a gallon? That Yukon sure burns good!
Put all these together, and it's little wonder that some of the folks accused and convicted of this sort of thing are convicted and jailed. Many are poor, and get lousy lawyers- juries are likely to convict on scant evidence when the alternative is to let a possible firebug out on the streets.
Fortunately, there are improvements, and the standards for training have gone way the heck up in past years. Certification under some standard for training is often required for the job, as well as continuing education to stay on the job. Engineers, chemists, modelers, and physicists tackle some of the more difficult issues with lab tests to back up what's being said in court. It's one thing to say that a steam pipe at X degrees for Y years can eventually cause enough pyrolysis of nearby wood to create open flame; it's another to have some PhD back it up with experiments that prove it, possibly exonerating the accused.
Sometimes folks believe strange things from way the heck back in their training. This is part of the legend behind "spontaneous human combustion." The '921 says in it somewhere in a straightforward (and vaguely comforting) manner that humans do not spontaneously combust. Now only if we can do that with the other bits of legend that investigators have clung to over the ages.
I broke the scaphoid bone in my right hand, a little cashew-sized thing that is easy to break. ER visit was $700 (covered by insurance) for one X-ray on a machine in a room with a cracked window for the operator to look through. Went to a hand specialist at the Mayo Clinic who immediately took new films on a digital machine- they were sent upstairs by wire, no hard copy ever made, and the resolution was much better. The first X-rays were awful in comparison. Still broken, so I had a composite cast put on, which went all the way up to mid-bicep (for a bone in my wrist!). After two weeks, new cast- this one up to mid-forearm. I think I went through three casts total, with X-rays after each was taken off. Total cost- from the Mayo- $1900.
Insurance wouldn't pay for it, as the Mayo isn't a preferred provider. They gave me the one-time-only $500 payout for this sort of thing; I paid $1400 out of pocket. The first bill arrived 14 MONTHS after my last cast was taken off; Arizona requires bills must be received by customers within 30 days, or something like that. I could have weasled out of it because of the billing delays, but- hey, I got what I paid for, so I coughed up the money since my hand works great. Had to drive a stick shift in Phoenix traffic like that for a month and a half, but it was a lot better than getting the bone screwed back together- invasive surgery.
Most likely it's a system where prilled or powdered salt is tumbled through dry air to absorb moisture; it's then roasted to release the moisture, captured under reduced pressure to reduce the amount of energy required, and returned to its anhydrous state. It'll be clumpy and chunky, so it'll have to be re-ground into a fine powder before reuse.
The $.30 a gallon is probably largely from the amount required in the removal of the water from the hydrate; distillation of water runs ~$.25 a gallon (assuming no recycling of the waste heat from condensation to pre-heat water going into the boiler) at $.10/kwh. Using gasoline or diesel would be considerably more expensive- thus the reduced pressure.
Distilled water from air- not too shabby. I've thought about trying the same here in the desert (where it's routinely ~10% RH in Phoenix), but it's just not worth it.
(imispgh is apparently the guy in the video, judging by his other posts, FYI)
A number of systems will resist this type of attack. Probably the best is the Abloy, which I understand was bought out along with ASSA by Medeco. Alboy relies upon a sidebar; the discs need to be aligned, a sidebar drops into place, and the lock opens. I also understand there is a way to bypass this system, although the tools are pricey, resticted, and since Abloy locks are relatively rare in the United States, they remain relatively secure.
ASSA also relies upon a sidebar, with the code being cut into the side of the blank. The blanks are heavily restricted, and locksmiths have to account for all of them- even ones that are mis-cut. Of course, a sidebar can be regional, which is its biggest flaw; apparently they are more popular in Europe. If a local locksmith uses a given key profile, then it is simple enough to turn a given cut key into a "bump" key.
It would seem- although I have not tested it- that Medeco locks are immune; they require that the pins be brought to the correct height and that they be rotated (left, center, right- only three possible combinations) before the lock will open. Last I checked, it was still much easier to grind a Medeco out of existance than it was to pick it; they *can* be picked, but it takes many hours. I never liked Medeco, but since Abloy and other types of locks that offer higher security than hardware-store junk were either insanely expensive or no longer available, as their keys tend to be brittle and break right at the bow. But that's what I installed on the house; each door cost me $160 for a single-cylinder lock, but at least I know the lock is secure. Entry would have to be made in some other way than bumping or picking; further, high end locks also offer crush-resistant collars (to avoid "pipe wrench" attacks), better bolts (to prevent icepick and cutting attacks), and so forth. They just *weigh* more- it's not pot metal and good intentions in every box, unlike some makes.
True story: in the early 1990's, some genius figured out that every high-security door lock on the market could be attacked in seconds- sometimes faster than using the key- with an ice pick or a bit of wire or welding rod. Pierce the door in the right way that the tool can be used to push back part of the bolt, and you're in. Ice pick attacks were popularized, but the wave of thefts never manifested. Newer generations of bolts were issued that prevent this type of attack.
"Bumping" presents a somewhat higher threat level given that it works on more commonly available locks, which are used on probably 95-99% of homes in the United States. Given that a "Kwikset" can be bypassed with a sheet metal screw, a screwdriver, and a pair of "Vice Grips," it's a wonder more homes don't succumb to this sort of stuff every day. Fortunately (?), thieves rarely look at a home the same way we do; a good burglar or a drug addict desperate for a $20 fix will use whatever tools and techniques are handy, at great expense to society. Given that these individuals might be able to sell their gains for perhaps 10% of their value, the amount that either has to steal and re-sell to get by is quite remarkable. They don't pick locks, and they probably won't use "bump" keys.