I've never really figured this out: Does the rate of heat transfer depend on the temperature differential or temperature or is it constant? Ficks first law implies that it does, but i could always be wrong
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# ? Jun 11, 2024 07:01 |
I would think dependent on temperature differential but it's been a while since I took thermo
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Watermelon Daiquiri posted:I've never really figured this out: Does the rate of heat transfer depend on the temperature differential or temperature or is it constant? Ficks first law implies that it does, but i could always be wrong So it's kind of inaccurate to say heat transfer rate is the same between you and 100c liquid water and you and saturated 100c steam because the convection terms aren't going to line up the same between a liquid and a gas and condensation is its own kinetic screwball.
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zedprime posted:Iirc temperature differential is always directly related to heat transfer rate. That doesn't mean it's the most important factor though because there is such an important kinetic component to heat transfer. It's accurate to say steam fucks you up far more than liquid water at similar temperatures. Energy from condensations gotta go somewhere too. Ouchies. Edit: yeah I'm too lazy to look for the correct coefficients. Mustached Demon has a new favorite as of 23:04 on Oct 12, 2017 |
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I've always found it hilarious that NaCl is two poisonous elements that when mixed together produces a stable compound that is a necessity for life.
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Watermelon Daiquiri posted:I've never really figured this out: Does the rate of heat transfer depend on the temperature differential or temperature or is it constant? Ficks first law implies that it does, but i could always be wrong This video talks about this in the context of when you should add milk to your tea (the result ends up being that you should add the milk right away because of the temperature differential affecting the rate of heat transfer.) https://www.youtube.com/watch?v=CCuaWqhVvIc
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Anyway I was distracted when steam chat first started but the pucker factor for boiler explosions and other steam explosions is just pressure. Steam provides some special concerns considering its usually worked with around saturation conditions which can cause a lot of pressure to appear or disapear if not properly managed, but the blowing up is chemical potential energy from pressure. The amount of chemical potential energy that can be turned into kinetic energy with any gas is slightly insane. At one point I was working with a chemical production unit that a large portion ran at 500 psi, but with a liquid to vapor fraction that was, if not comforting, was understandably under control. The difficult part is it was high hazard corrosive service and there was no state of the art to pressure test it: gas testing was an amount of energy that was just unallowable, which meant a failure with possible explosion would have caused a shockwave that would have killed anybody outside on the premises or something ridiculous, fluid testing there was no compatible fluid with the eventual contents which meant cleaning would be impossible and risky, and not doing it at all and slowly ramping up with process chemicals would have leaked like a sieve from all the half assed un torqued etc. flanges that are a fact of life in any plumbing construction. I forgot what they even did, the plan was tentatively switching from one back to the other up till the actual test, which I had a day off during. Anyway, back to steam. Boilers are static, turbines have moving parts but they are all on the inside. The really interesting steam vessel is the yankee dryer. A yankee dryer is just another roller in paper making specifically for creping tissue paper - pulp is stuck to it then scraped off with a giant razor blade. Also to help dry the pulp and stick it to the roller, its full of steam. A giant can of steam rotating like a roller. That is constantly scraped with a giant razor blade. If it stops spinning and hasn't been emptied, condensation collection could (and has in the past, which is how they know) cause temperature differentials across the thing that would crack it in half, letting all that chemical potential of pressurized gas turn into kinetic, blowing the gently caress up. In other words you'd have a hard time wiping your rear end without a giant spinning bomb.
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Mustached Demon posted:
PYF Dangerous Chemistry: Steamy Ouchies
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Speaking of Tea, there's an ISO standard for making tea. https://en.wikipedia.org/wiki/ISO_3103 https://www.youtube.com/watch?v=9mAcJRFfAL0
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quote:This standard is not meant to define the proper method for brewing tea, but rather how to document the tea brewing procedure so sensory comparisons can be made.
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There's also an ISO standard for peanut butter! it's for allergy testing purposes
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Is there an ISO standard for ISO standards?
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Grundulum posted:Is there an ISO standard for ISO standards? ISO/IEC 17065:2012 Conformity assessment -- Requirements for bodies certifying products, processes and services
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zedprime posted:Anyway I was distracted when steam chat first started but the pucker factor for boiler explosions and other steam explosions is just pressure. Steam provides some special concerns considering its usually worked with around saturation conditions which can cause a lot of pressure to appear or disapear if not properly managed, but the blowing up is chemical potential energy from pressure. The amount of chemical potential energy that can be turned into kinetic energy with any gas is slightly insane. At one point I was working with a chemical production unit that a large portion ran at 500 psi, but with a liquid to vapor fraction that was, if not comforting, was understandably under control. The difficult part is it was high hazard corrosive service and there was no state of the art to pressure test it: gas testing was an amount of energy that was just unallowable, which meant a failure with possible explosion would have caused a shockwave that would have killed anybody outside on the premises or something ridiculous, fluid testing there was no compatible fluid with the eventual contents which meant cleaning would be impossible and risky, and not doing it at all and slowly ramping up with process chemicals would have leaked like a sieve from all the half assed un torqued etc. flanges that are a fact of life in any plumbing construction. I forgot what they even did, the plan was tentatively switching from one back to the other up till the actual test, which I had a day off during. God I love living in the future.
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Having had both a steam burn and a high temp water burn (90+) I can tell you that I yelled when the water splashed over my hand, But with the steam I made no sound at all because it was one of those things that is so suddenly, shockingly painful that you just pull away without making a sound. It felt like my whole hand caught fire. loving valve packing was leaking so when I opened it it shot straight up the spindle ![]()
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I have recently been spending more and more time hanging out in the chemistry lab at work chatting with faculty about energetic reactions. At this time, members of the IT department are not allowed to grab chemicals and experiment with them. I am currently looking into auditing or taking courses because it sounds fun. The professor suggested that I would enjoy the film The Wages of Fear, in which four men are recruited to transport large amounts of nitroglycerin over rough roads to the site of a gas fire at an oil well so that the explosive can be used to blow out the fire.This thread might need a movie night.
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You could also consider Sorcerer, which is a later film based on the same novel.
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I saw this image, and thought of this thread.![]() Throwing FOOF at someone wouldn't just stun them briefly, though.
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Zemyla posted:I saw this image, and thought of this thread. The bitch was ODing!
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Speaking of comics, one of our other favorites just showed up in a webcomic.![]() (For context, Mr Kornada there is a rich idiot that almost caused a negligent genocide in order to be richer. The affluenza defense managed to take his sentencing from 'the most inventive torture anyone on the planet can invent' to being fined most of his assets and sentenced to work at a 'normal' job until he racks up I think it's 1000 days of satisfactory performance. Also the planet isn't completely terraformed yet so the primary source of protein is insects, thus the cricket burger.)
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Keiya posted:Speaking of comics, one of our other favorites just showed up in a webcomic. Which webcomic is that?
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And what exactly is the history of Kornada-san and why is he being persecuted for his beliefs?
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Magnus Praeda posted:Which webcomic is that? E: Rereading that section, the sentence isn't merciful because of affluenza, it's because he's being judged by a jury of his peers, including robots who are very big on the idea of rehabilitation through honest work. I will also note that the robots are the people he was trying to genocide. darthbob88 has a new favorite as of 18:55 on Oct 13, 2017 |
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darthbob88 posted:Freefall. Pretty good and fairly solid on the science, but glacial pace. It's been on the internet about as long as I have, and has only covered a few weeks to a couple months of actual plot. ![]() Also, the website looks like it's not changed since 1998. I'm amazed there's not some text on there using the marquee tag.
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Zemyla posted:I saw this image, and thought of this thread. ![]() or in case anyone needs an avatar: ![]()
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Jabor posted:You could also consider Sorcerer, which is a later film based on the same novel.
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Hubis posted:
I decided to make the avatar transparent, if any of you prefer that. ![]()
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Magnus Praeda posted:I'm amazed there's not some text on there using the marquee tag. Maybe there is - wasn't the marquee tag deprecated, and browsers no longer render it?
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Duodecimal posted:Maybe there is - wasn't the marquee tag deprecated, and browsers no longer render it? Browsers render the marquee tag as plain text. But there aren't any on the Freefall page, I've checked.
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Zemyla posted:Browsers render the marquee tag as plain text. But there aren't any on the Freefall page, I've checked. This. Also, there's no blink tags on there as far as I can tell. Still a very "web 1.0" looking site.
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That's why you use CSS animations to recreate those tags for that web 1.0 look.
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Instant Sunrise posted:That's why you use CSS animations to recreate those tags for that web 1.0 look. I hope and believe that somewhere out there, a webpage is using the absolute cutting edge of modern CSS and JS as a shim to keep their eye-searing 1998 webpage displaying as intended.
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Computer viking posted:I hope and believe that somewhere out there, a webpage is using the absolute cutting edge of modern CSS and JS as a shim to keep their eye-searing 1998 webpage displaying as intended. http://cheese.blartwendo.com/web21-demo.html
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So a friend of mine is curious. How does one store superacids? In glass, plastic, some sort of supercompound?
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iospace posted:So a friend of mine is curious. When you do make it, the equipment is probably made of nickel alloy. I forget the compatibility with fluorinated plastic, I think that's an option at room temperature for the fluorine based ones at least. Nickel alloy is loving magical.
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iospace posted:So a friend of mine is curious. inside Aliens
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Ha, in the spirit of Reinventing the Hyperlink.
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Computer viking posted:Ha, in the spirit of Reinventing the Hyperlink. I have no idea what the gently caress that is. Did he try/succeed in making a hyperlink without the normal syntax as a joke?
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oohhboy posted:I have no idea what the gently caress that is. Did he try/succeed in making a hyperlink without the normal syntax as a joke? I believe that's a precise summary, yes. (Possibly as a a result of overexposure to wheel-reinventing frameworks.)
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# ? Jun 11, 2024 07:01 |
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Computer viking posted:I hope and believe that somewhere out there, a webpage is using the absolute cutting edge of modern CSS and JS as a shim to keep their eye-searing 1998 webpage displaying as intended. Marquee is still supported (scroll up a bit there to see it in action!), and mimicking blink is like the canonical tutorial use of CSS animations.
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