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silentsnack posted:if you really believe in yourself and put in enough effort you can die of anything you set your mind to. I don't want it but it's nice to hear that that was a minor fuckup compared to everything else i've done.
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Jan 5, 2023 17:31
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CainFortea posted:Eh, the pipes are all pvc so it's not going to do anything with the lye. And this is preventative since we can't snake the shower and trying to snake under a toilet is a whole thing since you have to take the toilet off. Like its basically OK but you're reducing the life span of your drains if nothing else. I do it more than I should but I also have a drain system in need of reno that already leaks like a sieve into the yard. A real snake can go through the toilet trap itself unless you have a really funky low flow. Showers should have an access panel to where the trap is unless again, discount construction. Hand cranked snake is the best investment I've ever made.
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Jan 5, 2023 17:32
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zedprime posted:A real snake can go through the toilet trap itself unless you have a really funky low flow. Showers should have an access panel to where the trap is unless again, discount construction. A snake can go down a toilet but you risk scoring the porcelain to do so. They make toilet snakes with a rubberized bend at the end and no edges on the outside but they only go about 4 feet.
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Jan 5, 2023 19:14
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wow please tag and spoiler your post if you're going to talk about animal cruelty. poor snakes 
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Jan 5, 2023 19:28
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Synnr posted:Afaik u-235 gets used to produce some Medical isotopes but isn't used as such. Really it's just a heavy metal with some extra nasty, there's other heavy metals if you need some awful complex. And I expect it's half-life and dosing rate isn't useful for like a radiation seed. U-230 is a candidate for targeted alpha therapy, but only in the sense that it decays to Th-226 which is what is what is delivered to the patient. namlosh posted:Unrelated question: does anyone know specifically the legality of tritium keychains in the US? Is there a special carve out for them or ???? https://www.nrc.gov/reading-rm/doc-collections/cfr/part030/part030-0019.html Summary: You need a license to manufacture products that incorporate tritium, but if someone overseas makes them without a NRC license and through some chain of events one of them winds up in your possession then you're still in the clear unless the stuff is "used in products primarily for frivolous purposes or in toys or adornments." I don't think they've ever gone after end-users for keychains, though, or that there's any caselaw defining them as 'frivolous.' Phanatic has a new favorite as of 20:59 on Jan 5, 2023 |
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Jan 5, 2023 20:48
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If you're going to "snake" your drain in any way, you pretty much always have to dismount your toilet to get it in properly. I'd generally suggest going up the other way rather than down the toilet, since immediately past the toilet when everything still has plenty of velocity, is where it's unlikely to start clogging. Your clog is almost always going to be in the long almost-flat out to the main pipe in the road, and often closer to that pipe than to the toilet. It's obviously a bit more work and a bit grosser to lift off a sewer lid and popping the snake up from the outside in, but it's liable to be far more effective. Also rather than the strictly mechanical snakes, something I find is quite good is you can get these heads for garden hoses that shoot water out "backwards" so they essentially use water pressure to force themselves through clogs. Garden hoses tend to be more flexible than the metal snakes and the water pressure is likely to get more force applied.
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Jan 6, 2023 02:47
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namlosh posted:As someone who has a lot of fake teeth, teeth are wierd. My current ones took weeks to grow in a lab run by some guy. From what I recall, the material is also semi-translucent, and built up layer by layer to make the tooth which turns out white in the end. The lab guy had a lot of cool looking equipment. Keychains are considered “frivolous use” by NRC and thus are forbidden. It is however totally cool to have a tritium vial used for lighting a e: Beaten like a DOE agent got me with the butt end of their Colt 633. Platystemon has a new favorite as of 03:14 on Jan 6, 2023 |
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Jan 6, 2023 03:11
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What if the keychain has the key to my gun safe, and I need to be able to quickly locate it even in the dark in case of sudden Communists?
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Jan 6, 2023 03:16
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Platystemon posted:Keychains are considered “frivolous use” by NRC and thus are forbidden. Don't gently caress with the energy cops or with SA reply speeds
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Jan 6, 2023 03:57
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Sagebrush posted:It's not for color, exactly, but for fluorescence. Real human teeth are slightly fluorescent (think about what it looks like when you smile under a blacklight) but the ceramics used for false teeth and repairs are not. This means that the false teeth would always look a little bit dull and gray beside natural ones, particularly in sunlight. Adding just a touch of a fluorescent element brightens them right up! Interesting, and makes sense. The document I read was a little older (80s or 90s) and referred to it as a colorant but that might have just been an oddity in the language. Phanatic posted:U-230 is a candidate for targeted alpha therapy, but only in the sense that it decays to Th-226 which is what is what is delivered to the patient. That's purely as a generator source for the thorium in funky SPE setups, isn't it? I was angling at the "put it in your body" side, given the question, but now I'm curious if the folks who do all our radiation stuff would have interesting/odd products to discuss. Fluorodeoxyglucose (really, most of the radioactive tracers) is super cool, if not necessarily that dangerous. Similarly, the first time I ran metabolic analyses with doubly labeled water was (kind of still is, though I haven't in a couple of years) very exciting and strange to be doing. They just aren't radioactive.
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Jan 6, 2023 07:38
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PurpleXVI posted:It's obviously a bit more work and a bit grosser to lift off a sewer lid and popping the snake up from the outside in, but it's liable to be far more effective. Also rather than the strictly mechanical snakes, something I find is quite good is you can get these heads for garden hoses that shoot water out "backwards" so they essentially use water pressure to force themselves through clogs. Garden hoses tend to be more flexible than the metal snakes and the water pressure is likely to get more force applied. I have access to a jetter if it ever came to that. Instead I just lye the shower once a year ish and don't worry about it anymore.
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Jan 6, 2023 18:01
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Does FOOF have any real uses?
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Jan 6, 2023 20:58
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Platystemon posted:I made soap with a large excess of lye once, and it wasn’t that bad. https://forums.somethingawful.com/showthread.php?threadid=3602006&userid=84040&perpage=40&pagenumber=6#post527889231 Are you sure about that? I mean, never trust something who's heart is full of lye
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Jan 6, 2023 21:06
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Low temperature synthesis of plutonium hexafluoride, apparently. Otherwise it's (even more of) a gimmick. I guess if you desperately need to oxidize an organic into nothing and want to terrify your labmates?
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Jan 6, 2023 21:06
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Nebakenezzer posted:Does FOOF have any real uses? It's a gimmick chemical to scare undergrads into respecting fluorine chemistry.
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Jan 6, 2023 21:09
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Cmon nobody is going to say rockets? 
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Jan 6, 2023 22:28
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Nasty tri and hexa fluorine stuff gets used in chip manufacture
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Jan 6, 2023 23:56
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Dang It Bhabhi! posted:Cmon nobody is going to say rockets? Highest specific impulse chemical system ever was a tripropellant mix of hydrogen, ClF3, and lithium.
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Jan 7, 2023 00:34
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Phanatic posted:Highest specific impulse chemical system ever was a tripropellant mix of hydrogen, ClF3, and lithium. Uh I think you'll find FOOF and dimethylmercury outperforms everything.
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Jan 7, 2023 01:20
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Phanatic posted:Highest specific impulse chemical system ever was a tripropellant mix of hydrogen, ClF3, and lithium. 
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Jan 7, 2023 01:31
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Phanatic posted:Highest specific impulse chemical system ever was a tripropellant mix of hydrogen, ClF3, and lithium. 
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Jan 7, 2023 01:53
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Phanatic posted:Highest specific impulse chemical system ever was a tripropellant mix of hydrogen, ClF3, and lithium. gently caress NO!
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Jan 7, 2023 02:08
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Humbug Scoolbus posted:gently caress NO! What did NO ever do to you? 
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Jan 7, 2023 02:13
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Icon Of Sin posted:What did NO ever do to you? Bought them dinner?
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Jan 7, 2023 04:45
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Nebakenezzer posted:Does FOOF have any real uses? Making things go away?
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Jan 7, 2023 13:05
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ClF3 is used to clean reaction chambers in semiconductors. Pump gas in, it burns all the SiX off, and you get a clean chamber without having to take it apart. Useful when taking something apart to clean it takes a ton of time and will probably introduce contamination everywhere.
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Jan 7, 2023 19:03
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Phanatic posted:Highest specific impulse chemical system ever was a tripropellant mix of hydrogen, ClF3, and lithium. Seems more like a dare than a propellant fake e: twit that at Elon Musk
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Jan 7, 2023 19:08
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If anyone wants details: https://arc.aiaa.org/doi/pdf/10.2514/6.1968-618 https://ntrs.nasa.gov/citations/19680007319 542 seconds, so a significant but not *huge* improvement on LOX/H2, while presenting all the difficulties of handling ClF3 and molten lithium and cryogenic hydrogen.
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Jan 7, 2023 22:32
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The amounts of oxidizer put in one place for rockets is terrifiying enough without making it ClF3. Just using elemental fluorine came up at one point in the thread, due to Ignition or something, and had some magnitudes of what an F2 oxidizer tank would be for a space rocket and my industrial fluorine brain being like "that's more fluorine in one spot than anyone has tried before" just cause your goal with elemental fluorine is to use it right away.
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Jan 7, 2023 22:42
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Kazinsal posted:Winchell Chung's "Atomic Rockets" site updated recently, with one of the additions being a section on a 1966 study by Rockwell on a capsule-style Mars lander that ran on a delicate balance of liquid almost-FOOF. You get there with NERVAs, with Fluorine Liquid Oxygen (FLOX)used for corrections and excursion ascents etc. because FLOX-CH4 systems are very energy dense and hypergolic so you don't even need a separate igniter which adds mass or can break.
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Jan 7, 2023 23:02
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Phanatic posted:If anyone wants details: I'm reading this paper and it's liquid difluorine, liquid hydrogen, and molten lithium. Thankfully, no ClF3 is needed. Just cryogenic fluorine, cryogenic hydrogen, and molten lithium. I'm sure that simplifies.... something.
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Jan 7, 2023 23:53
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babyeatingpsychopath posted:I'm reading this paper and it's liquid difluorine, liquid hydrogen, and molten lithium. poo poo you’re right why was I remembering it as trifluoride.
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Jan 8, 2023 00:00
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Phanatic posted:poo poo you’re right why was I remembering it as trifluoride. "gas phase reactions of fluorine with hydrogen, fluorine with lithium, and lithium with hydrogen fluoride, even at the lowest temperature likely to exist in the combustion chamber, are more rapid by several orders of magnitude..." "Chamber pressure variation (200 to 1000 psia) has little effect on vacuum specific impulse." "gas-augmented atomization of a liquid metal... [with a] lithium injector containing showerhead F2 orifices which produced gas jets into which high-velocity liquid lithium streams were injected""" Sounds like a grand old time.
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Jan 8, 2023 00:51
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babyeatingpsychopath posted:"gas phase reactions of fluorine with hydrogen, fluorine with lithium, and lithium with hydrogen fluoride, even at the lowest temperature likely to exist in the combustion chamber, are more rapid by several orders of magnitude..."  
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Jan 8, 2023 01:27
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babyeatingpsychopath posted:"gas phase reactions of fluorine with hydrogen, fluorine with lithium, and lithium with hydrogen fluoride, even at the lowest temperature likely to exist in the combustion chamber, are more rapid by several orders of magnitude..." The real fun starts when you have to design fuel tanks for such an engine, given the wildly different temperatures required for each of these three chemicals (-252°, 180°, and -219° centigrade). Not to mention setting up facilities to produce enough fluorine to fill those tanks. And what happens to all the HF and other delightful corrosives and toxics the exhaust contains. There's a reason that nobody's built this type of motor despite the amazing specific impulse (542 m/s) you get from it. Vincent Van Goatse has a new favorite as of 01:50 on Jan 8, 2023 |
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Jan 8, 2023 01:47
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Vincent Van Goatse posted:The real fun starts when you have to design fuel tanks for such an engine, given the wildly different temperatures required for each of these three chemicals (-252°, 180°, and -219° centigrade). Not to mention setting up facilities to produce enough fluorine to fill those tanks. And what happens to all the HF and other delightful corrosives and toxics the exhaust contains. Also the more exotic/toxic the fuel and combustion products are, the more exciting it'll be to solve the logistical puzzle of "how best to defuse the 300-ton bomb?" when a launch is canceled; because as mentioned a lot of these substances aren't something you especially want to keep in storage
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Jan 8, 2023 02:30
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I suspect that with how complex your tankage is going to be you're mass fraction is going to be a lot worse than a kerolox or hydrolox engine. At that point you might as well just use a kerolox first stage and make up the efficiency losses by using a solid-core NTR upper stage. Way less of a pain in the rear end to work with (and even solid-cores can get up to about 900 seconds isp or so).
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Jan 8, 2023 02:46
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Double posting for the glory of the Soviet Strategic Rocket Forces;
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Jan 8, 2023 02:48
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LostCosmonaut posted:Double posting for the glory of the Soviet Strategic Rocket Forces; What is an RD-600
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Jan 8, 2023 02:59
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Hexyflexy posted:What is an RD-600 This quote:Glushko nuclear/LH2 rocket engine. Gas core nuclear engine worked developed 1962-1970 for use in second stage of two-stage interplanetary rockets. But the table appears to refer to the RD-0600, which is something else: quote:Kosberg laser rocket engine. Space station "Skif". Developed 1970-85. Gas dynamic laser. Working medium gaseous carbon monoxide + air + nitrogen + ethanol. Flow rate up to 100 kg/s. Tests were performed at NII TP. It appears that this was not actually a rocket engine, but a gas dynamic laser, probably intended as a weapon. Perhaps it's being classified as a rocket because it's a chemical laser that consumes its fuel to lase?  
Sagebrush has a new favorite as of 03:08 on Jan 8, 2023 |
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Jan 8, 2023 02:59
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