Added: 3 years ago
From: nottinghamscience
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  • The video, his hair, and the fluid in the chamber are all at equilibrium in this video. That was awesome!

  • 2:30 Took an arrow to the knee!

  • I was not interested because I did not really understand what was going on here(I have a BSc in computer science) - I think we need more background, expecting us to say "wow!" is not really fair given the lack of information you have supplied us with...

  • @jagara1 I don't understand the process either ( I have a degree in nothing,) but that's hardly relevant. The fact that it's something novel that you don't usually see fluids doing "should" be enough to pique your interest (if you're into these sorts of things.)

  • @jagara1 The surface tension disappears. I have no degree and was able to grasp it. You can see it happen.

  • @DubIDubblix Thank you so much for your explanation!

    Can you please now explain what surface tension is?

    Why when surface tension present a liquid behaves the way it does and why when it is not present the liquid behaves differently?

    "Seeing something happen" is a whole order of magnitude in difference to understanding and being able to explain why it happens!

  • @jagara1 You need to do some reading to understand surface tension. No one here knows how much you do or do not know already nor could we explain it to you without that knowledge. Hell, Wikipedia should have a long article that can answer your questions.

  • @DubIDubblix What a frickin' copout!

  • @DubIDubblix I asked two questions and you are completely unwilling/unable to answer either of them!

  • @jagara1 Hahahaha. I'm not your teacher nor do I owe you anything. Be proactive and go find the answers yourself. You're already signed into Google, try going to their homepage and typing in your question.

  • @DubIDubblix You said - "The surface tension disappears. I have no degree and was able to grasp it." - I just skimmed through the wiki on surface tension and am most impressed that you understand this area given the molecular and mathematical complexity of surface tension. It does not answer how when surface tension disappears that a liquid will flow up vertically though.I don't think you understand the slightest thing about this area which is why you have fobbed me off with visiting the wiki

  • @jagara1 You misunderstand. I don't care if you understand it. I learned surface tension in high school and while the math is complex, I didn't have problems understanding it. Its not my problem that you don't get it.

  • That video is so cool thanks alot for this educational video.

    I find this really fascinating aswell.

  • Why do physicists have to have that hair?

  • This guy is the typical professor.

  • Is it a liquid is it a gas is it something anyone cares about no.

  • @MrFatdubyman obviously you're ignorant.

  • Looks like he does sign language as the vehicle goes along.

  • So that's how the atmosphere on Venus is... Wow!

  • omggggg thats cool

  • I recognize the professor's voice :)

  • I'm just studying this right now and I find this video very educational, besides the teacher (I imagine he's got a PhD or many) explains himself in a very understandable way. Thanks a lot!

  • he sounds like salad fingers

  • Marty, we gotta get back to the future!

  • @itshelpa ahh ahaha thats cold

  • its kind of cool how you can have the liquid and gaseous co2 under the same pressure... If I could ask, what is the pressure in the containing vessel professor..?

  • what is the maximum p.s.i. in this demonstration? as well as the temperature in of the vessel Celsius?

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  • @threejchapman

    The maximum pressure in this experiment is not higher than 75bar.

    I have build such an apparatus and it gets supercritical at 31°C.

  • *Watching some videos about quantum mechanics*

    *Found the nottinghamscience channel*

    *Looks at clock- holy c***! 4:30 am already!?!*

    That's how awesome science is...

  • Supercritical fluids are awesome. Nice demonstration!

  • I working on solubility of salts right now learning about Ks. So how would the Ks value change in supercritical solvents than in conventional solvents? If you could ask the professor.

  • Future mad scientist? He has the hair...

  • Four people were suggested to go work with someone else.

  • I used to work with supercritical fluids. Turns out it was just a phasse I was going through.

  • @giantsquidrule HAHAHAHAHAHAHAHAHAHA fucking hi five

  • @giantsquidrule Oops. Mistyped it. Too late now.

  • @giantsquidrule i guess you parents stuck you in a sealed room

  • @giantsquidrule I too used to work with superfluids like you. Then I took an arrow to the knee.

  • @giantsquidrule i loled

  • what are the pressures this is happening at?

  • @killernat probably atmospheric pressure, so 1003 hPa

  • @wannabeers oh right i think he mentioned its SF6 at some point so yah the pressure would be decently low

  • mit der frisur würde ick och schlau aussehn :D

  • "Because I have nowhere else to put it"

    LOL

  • Nigga's the next Einstine

    

  • i had an interview today at professor Poliakoffs office!

    fortunately i allready knew this video ;) i totally freaked out when he showed me the machine

  • why freaking youtube people doubting the words of a professor. OO

    If u think u are better than him, prove it. ANd not be a keyboard warrior

  • thumbs up if you came to look at this after looking at phase diagrams in chemistry

  • CARBON DIOXIDE IS NOT POISONOUS???

    This is really unexpected and perhaps unwelcome information coming from the mouth of a professor!

    I understand that It's a matter of formulation but still... not from a professor, for crying out loud!!!

  • @yo6ial CO2 is not poisonous, literally. i mean it is for human beings and most animals but not for plants and that's only one example. the professor is correct when saying that.

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  • @ericon52168 I'd imagine that I have a pretty good idea about what poison and poisonous means.

    But, to my shame, I have no idea, whatsoever, about "meh" and "nvm" words are and, genuinely, no clue about what's that you're trying to say with "*headdesk*"

    I'm afraid you have a pretty high CO2 concentration in your blood stream. :|

  • @yo6ial alright, my bad being an ass

    but do you really think CO2 is poisonous ?

  • @ericon52168 I should probably say something like "I don't know... What _do you_ think?" ;))

    But I won't.

    Think that supercritical carbon dioxide fluid would be used in fabrication of some prosthetic.

    As a simple solvent, as the professor explained.

    That carbon dioxide would either be removed completely before implantation or it will be discarded into the patient's organism.

    Now, please read the wiki article Carbon_dioxide#Toxicity

    Cheers! :)

  • @yo6ial i went to that page just after seeing your 1st message

    in my mind, it still doesn't count as a poison

    you can also harm with oxygen or water, if enough is present, you can wiki "oxygen poisoning" and "Water intoxication"

    but does that mean oxygen and water are "poisons"?

    my definition of poison, and i think this is what people mean poison all the time

    is a subtance that can react within the body and thus stopping vital functions (such as CO binding to hemoglobin, cutting O2 supply)

  • @ericon52168 Entirely true, :) but carbon dioxide can do just as much harm as carbon monoxide, even if different processes occur.

    Even if the CO2 binds differently to hemoglobin and not actually displacing the O2 from it, it still severely decreases the amount of oxygen that can be transported.

    Any chemical compound or element can be considered as poison/poisonous if small amounts can cause severe organism malfunction.

    But I whose talking about a formulation issue. CO2 is not lethal in 2ppm.

  • @yo6ial i would like to see a diagram describing how CO2 interfer with O2 supply

    anything reaching-mechinism-ish will do

  • @ericon52168 Ok... I'll try. :D

    CO2 is mostly stored as HCO3 ions, in the bloodstream, but excess will cause acidosis .

    The increasing levels of HCO3 can only compensate.

    Acidosis is a cause for hypoxiation of blood.

    I'll also try to find out more about the chemical mechanism of low pH and oxygen transportation, but I suspect that it might have to do with Fe ions... :|

  • His hair is a supercritical fluid : D

  • lol now everyone that wants to work in his lab knows exactly how they should react to that video

  • 4 people are supercritical

  • that was the cooles experiment I've ever seen

  • great qualification gage. "whats that?"  It is an interest gage.

  • "carbon dioxide is totally non-poisonous" ... Really, Professor? Is that why we have to remove it from our bodies metabolically or we die?

  • What will this look like in zero gravity?

  • @madjimms

    well I have not been in space yet.. But I'd think that the liquid would coat the glass container it is in... since its a gas and has zero viscosity. if the liquid was supspended away from the glass container, I'd think when heated the suspended ball of liquid would cloud up with bubbles and emit a layer of steam around it . the layer of steam would expand until there was no more liquid left.. after that you should have a perfect layer of helium condensation on the glass container.

  • Actually you can die of CO2 poisoning even if there is sufficient oxygen along with it.

  • @MazeleyFanClub

    thats if you breath it in

  • Please live long! I want to work with you so badly! Sadly though, I must first get a piece of paper confirming that I am smart enough to do so... a couple years left to go!

  • I was already been told what supercritical-fluid was, but those explanations where much more clear to me !

    Thanks !

  • I would say wowww

  • WITCHCRAFT! 

  • @deo000000 ALCHEMY! this experiment was possible 200 years ago? maybe.

  • Brilliant! Can I work for you now?

  • CO2 is hazardous in a sufficiently high concentration. 

  • @Gammaclipper As an asphyxiant, not as a poison. You would die by breathing pure CO2 for 5 minutes, but because your cells would not receive oxygen, not by poisoning. Just like you wouldn't die by poisoning if someone was choking you.

  • @DevilMaster

    Actually @ 1% people will start feeling drowsy

    Staying @ 2% for several hours causes acidosis

    @ 3% breathing rate is 2X

    @ 5% breathing rate is 4X normal and the concentration becomes directly toxic

    Symptoms of high or prolonged exposure to carbon dioxide include headache, increased heart rate, dizziness, fatigue, rapid breathing, visual and hearing dysfunctions. Exposure to higher levels may cause unconsciousness or death within minutes of exposure.

  • @Gammaclipper

    CO2 has been used to slaughter animals in some experiments to determine a new method of execution but hypoxia induced by nitrogen asphyxiation was found to be less painful.

  • How can you not like this video? They're just supercritical people!

  • 3 people didn't like this video?

    must be the 3 he suggested work with someone else. lol

  • cool!! can i make that thing?

  • thats so awesome :D

  • oh god...that is so awesome!! i loved the little "storm" in there...i was just like O.O ...i really love supercritical fluids from now on..i just have to go and get some info's about it!!

  • @Defonthana ahh...is every fluid able to be supercritical? or do they need specific attitudes?

  • @Defonthana Yes, providing it is stable and does not decompose at the critical temperature and pressure, every substance can be made supercritical. For instance, some of the very efficient power generation plants use supercritical steam.

  • 1:30 - so technically this is cold plasma?

  • @Fusurugi No. Plasma is ionized gas.

  • That's the same monitor I use :) Interesting effect too.

  • This is my idea of nirvana:To see videos of sixty symbols, nottingham science and periodic videos with videos from the khan academy and it is even better if the professor is featured

  • i was never interested in chemestry (more biology) till i watched these videos. i find it so facinating

  • I wonder how it would look without the influence of gravity.........

  • I wonder how it would look without the influence of gravity.........

  • Fascinating!

  • this is absolutly FASCINATING!

  • Now I less than three supercritical fluids.

  • Prof...great experiment...i like it...:D

  • Einstein!  in the flesh! :D

  • They should do research on his hair.

  • @mlcoo17 You need to see the video where they etch a periodic table on one of his hairs. watch?v=cQU2IAsQak8

  • quite interesting

  • So awesome!

  • When I study this, reading a book, I didn't know exactly what the book was telling me... Now i'm so surprized. This is much more i thought It was

  • zomg its isac newton from the dead!!!

  • crazy einstein hair + ginormous glasses = instant smart cred

  • You have to watch this old video on Liquid Helium Superfluid. watch?v=S3O-5KTYq6o

  • It's cool to find out what struck him as fascinating and cultivated his chemistry passion.

  • Great explanation!  Very clear.

  • This same process is used to make decaf coffee.

  • I just would love him to be my Physics teacher... tha was awesome 0.o

  • I thought, if you breath and hold the breath until you feel bad, the CO2 made you to. It is poisonous if it's concentration is too high..

  • I know what you mean, but it is not POISONOUS. Cabon Monoxide is poisonous, because it harms the body, but what he is saying is it's not like 'OMG there's a giant cloud of CO2 coming to eat mee!!', so its safe :)

  • What 'e said. It's when the CO2 REPLACES the oxygen (as it does when you hold your breath) that you get into trouble.

  • ok he talked about CO2 as a solvent for some medicament- so the concentration of CO2 will be low in the blood. In this case it is non poisonous, until it's given in the right dose.

    Giving too much= poisonous. The same like CO or CO2 coming out of the ground.

  • @101status0

    CO2 can be toxic. Toxins and not necessarily poisons.

    Poisons are detrimental at any dose. Toxins are detrimental at high dose.

  • @KrokFryedRyce I lolled when you said "'OMG there's a giant cloud of CO2 coming to eat mee!!', so its safe :) "

  • I would have expected this as part of a physics demonstration, we're seeing physical properties of phase-changes that are done and undone by physical means.. Was this experiment initially discovered performed by a physicist?

    Why is it called a Super-critical Fluid, rather than a Super-dense Gas? Does the Super-critical Fluid have more properties related to fluids than gases? Is CO2 condensed to make this since at room temperature it's a gas already?

  • @Ducky1138 You appear to be unclear on the definition of fluid. In common speach they are often used interchangably but there is technically a difference.

    Simply put, a fluid can be any material which can flow, which includes gasses as well as liquids. The critical point is the point on a pressure/temperature graph at which the transition from two distinct phases (liquid and gas) to a single phase (as shown in the video) occurs. As this exists above that point it is called super-critical.

  • he looks like the archetypical mad scientist

  • What do you mean it's too dangerous!? There's no such thing! HaHAhahahahahaha!

  • This is an absolutely fascinating effect. It would be even more interesting if we tried this as a plasma in this kind of environment, it's stuff like this that makes me want to be a chemist O_o

  • This guy's my hero!

  • pssssh!!

  • That was interesting.

  • Does surface tension play a role in the "storm"? I did see more water stayed up on the sides of the container before "raining" down.

  • My reaction would be Wow! Unfortunately my next reaction would be Derrrr?

  • Wow that's interesting (now I wonder if I can send in my resume)

  • i got a friend called euan who wants a bifro like yours, but then he cut his hair off and grew a beard. RESPECT DUDE

  • Whoa that cats got a pimpin' bifro going on. RESPECT.

  • Martyn is my scientific idol.

  • yea, we should start a fan club.

  • dude, yes.  im completely serious too.

  • awesome hair dude!!

  • Supercritical fluids form the harshest environments in the world. If you need to destroy a chemical or do wastewater treatment, it'll definitely do the trick...if the container lasts that is. Even high density stainless steel doesn't stand a chance for long. Containing the supercritical fluid while using it in an application is a very important problem to solve.

  • @baguazhang2 you dont need to raise it to critical temperatures and pressures to clean out "bad" things. it can do that at a much lower temp than 300 degrees cel

  • Just because something isn't poisonous doesn't mean it can't hurt you. If you lock yourself in a room full of pure, non-toxic CO2 you'll not last long.

    But you don't have to worry about the CO2 in the global atmosphere getting high enough to suffocate you, because the heat it traps will make the planet unlivable long before that.

  • Sure, but you cannot use the word pollutant. Pollutant is for other stuff.

  • Depends on your definition of a pollutant. It fits the common definition:

    "Pollution: introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the ecosystem"

    But other groups only consider elements toxic to humans (such as Carbon Monoxide) to be pollutants.

    But all this detracts from the main issue, large amounts of man-made CO2 (mostly from burning coal, oil, etc.) is causing the planet to heat up at an accelerated rate.

  • Oh yeah it depends on definitions. But if you breathe CO2 for a long time then you stop, you have nothing bad left inside you. Try this with CO or with toxic substances. They will pollute your body.

    The main issue was the word not the world. And it is an hoax.

    I didn't talk about the global warming but about the global warmers and the incorrect use of a word.

    Let's use pollutant for the nice metal dust you breath in several cities. It is polluting a lot of people just now.

  • BTW CO is an impossible liaison

  • Wow. :)

  • That's definitely a good start on solvent use. It'll save lots of time and money. Solvents go through grant money like a kid goes through a pack of gum. :)) Seperating and repurifying solvent is time consuming which slows down progress, and also happens to be tedious. Just looking at it though, you know there'll be a breakthrough for more practical applications.

  • it's great!!i love it!

  • listen to the end!!

  • For the people who dont see the benefits of this, you didnt watch to the end of the video. The professor explains a potential use.

  • in laparoscopic surgery, u need to expand eg the abdominal cavity temporarily; you use CO2 there n plenty more other uses

  • what the significance of this? a cool experiment, but what does it show other than the obvious. what does this man research using this information?

  • Ha ha Albert Einstein hairdo!

  • you mean lack of hair care, right?

  • can someone please explain this to me? i just dont understand why its so awesome? is gas half the density of a liquid something huge? haha im sorry

  • The significance is from 3:43 to the end. Since you can use the supercritical fluid as a solvent instead of an inorganic solvent, it would be useful in medicine where an inorganic solvent introduced into an organism might be harmful, for example.

  • oh ok thanks

  • johnlebl - I don't see a useful application of this in medicine because living tissues will not survive the pressures at which these fluids operate.

  • Sorry, oomblikkies, I guess I didn't explain what I meant very clearly. If you needed to use a solvent in the manufacture of a replacement body part, maybe a mechanical heart or pacemaker, then a supercritical fluid used as a solvent would be a better choice than say, benzene (random example) that might remain residually and leach out. No body tissues need be harmed by the pressure ;p

  • There are a ton of other applications as well. Like I just mentioned in my mast post, you can run wastewater through a supercritical fluid to destroy the bad things and get clean water. Supercritical water forms an extremely, extremely harsh environment.

  • Does this apply to the weather? The reason why there are storms.

  • I, for one, would constitute a part of the "Wow!" crowd of interviewees. :-)

  • One little mistake in the vid: At 1:12, the professor says that "... eventually they become the same density, and the line in between it, completely disappears".

    The two phases do not necessarily have to have the same density in order for the dividing line to disappear, but the same relative index of refraction. This is often demonstrated by sticking a glass spatula into a clear liquid of the same refracion index of the spatula: The part of the spatula that's in the liquid, becomes invisible!

  • Yes, but in this case the materials are the same, so the indices of refraction will be the same exactly when the densities are the same. :P

  • Wow that is very fascinating.

  • Can lower temperature supercritical fluids be used as lubricants, or as a suspension matrix for industries ? It would appear that they have a greater measure of "slipperiness"

  • WOW

  • I've done more exciting farts

    however they were also supercritical fluids

  • first time i saw this o got hoocked. this man has convinced me to become a chemist

  • awesome! i love him!

  • lol i totally passed that test, i was rivetd, and was all heart eyes when it recondensed :D

  • xD No offense.

  • Some questions: 1.What kind of a liquid could it possible have a supercritical temperature of about 60 C?

    2. If the liquid is contained in a closed vessel, how come the boiling temperature does not increase with the vapor pressure of the liquid?

  • actually this one is kind of simple the atoms have no where to go while trying to move more, creating an expenonential growth effect temp wise, as the temp goes up the gas already, having no where to go the molecules rub and eventually do that =) (my guess)

  • It *does* increase the pressure. In fact if you look at a phase diagram at the triple point you can see what the pressure will be. That's why you need to take the pressure into consideration for your vessel design strength.

  • CO2 32ºC

  • Very interesting! I was studying isothermal curves of a real gas, but I didn't understand them very much. I couldn't imagine a supercritical fluid and on my book there was written that it's impossible to see it. Thanks to my favourite chemist!

  • thanks

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