Even a simple google reveals this, look here [howstuffworks. Go back to your cave, troll. Plazanet and colleagues prepared a liquid solution containing a-cyclodextrine alpha-CD , water and 4-methylpyridine 4MP. Cyclodextrines are cyclic structures containing hydroxyl end groups that can form hydrogen bonds with either the 4MP or water molecules. And if you expect me to tell you how this discovery will modify our lives, you're going to be disappointed.
I've not a slightest idea about it, even if I find fascinating that scientists always find new ways to break rules and shake our certitudes. I am a chemist that has discovered a class of mixtures with a very interesting and heretofor unobserved property.
I have published information on how to prepare these mixtures--in a way, it is a solution looking for a problem. I expect that given a small group of engineers, a dozen or so different applications could be hashed out over their morning coffee. I am disappointed--but not surprised--that a Slashdot reader couldn't be bothered to use his imagination to come up with an application, preferring to instead complain that no ideas were spoon-fed in the brief PhysicsWeb note.
Anyway it has been known for many years that some triblock polymers form gels when heated, but perhaps the solid phase of this new liquid is "more solid". Perhaps the news is that the liquid has a larger enthalpy of melting. I don't know. Reinforcement for solid structures. Somebody already mentioned skyscrapers, but I'm also envisoning other more improbable structures, like hurricaine proof buildings.
Wind blows, soften up the beams and let her bend a bit. Wind stops, stiffen the supports back up. This has to be used in mecha. Beams that can bend a bit, be solid or fluid, would be excellent in 50 foot killer robots. You know it. Tank armour. Make it solid and when stuff hits, it breaks. Change temperature, and it melts.
Change temp again and it becomes solid again, with no signs of previous damage. Regenerating armour. No need; conceptually it's easy enough: each of the aCD moledules gets bent out of shape by the heat, thus exposing more sites for hydrogen bonds to form, allowing the solidification to occurr. Since these molecules are capable of snapping back into the previous shape when cooled, they are therefore storing energy.
And so the solid is still in a higher-energy state than the liquid. From what I gather in the article, the solution turns solid when heated between C.
Beyond that it probably either burns or melts again. Those temps are much too low to have any impact in a fire. That said, your idea could be made to work in other cases.
I wonder if maybe the substance could be altered for use as a variable damping material for suspension or acoustic purposes. First, the World Trade Center collapsed because jet fuel burns extremely hot. The WTC design was actually far stronger than most other skyscrapers standing today. Notice that the building survived the initial impact of a plane, and that it wasn't until later, when the intense heat of the burning fuel had time to weaken the steel support structure that it collapsed.
A normal building fire would not have threatened the structural integrity of the WTC because there was nothing in the WTC that was hot enough to melt the beams, until the plane, full of fuel, arrived. Second, I didn't notice in the article whether the volume of the material expands or contracts when it turns solid.
If the hollow beam is partly filled with liquid because the liquid expands when frozen then there isn't necessarily enough contact between the liquid and the burning sections of the building to protect the upper portions of the beam.
The beam will conduct some of the heat to the liquid, but depending on where the fire occurs in relation to the beam, the top of the liquid might freeze first, leaving the upper portion of the beam hollow.
If the liquid contracts when frozen, you end up with a partly filled beam, which isn't necessarily stronger than a beam with nothing in it. This leads to the third point, that nothing is mentioned about the structural properties of the liquid when frozen.
Steel behaves extremely well under tension, and concrete under pressure. Thus, they complement each other quite well which is why we make buildings out of them. Would the liquid make a better replacement for the steel, or the concrete? And would it perform equally well when the building is not on fire? Has having liquid-filled cavities in the building strengthened or weakened the structure, for the large majority of the time?
Finally, does the cost of using a material like this justify it? It's new, it probably costs more than steel to use in a building. Wouldn't redundant support structures be more reasonable?
Or, using a design like the WTC, which I noted only failed from the heat of burning jet fuel? That would probably depend on the property of the solid that forms when the solution is heated is it a good insulator? The solution is transparent to visible light, whereas the solid that forms is not. Since this process depends on the temperature and is reversible, it's very simple to design a circuit using a LED and phototransistor or some sort of photo-detector that works as temperature-dependent switch.
From what the article says,. But then, this is not anything new--as far as dependence on temperature goes, there are many other materials that are probably more reliable the only thing novel about this would be that its dependence is backward. Back to the topic, yeah, it can probably be used as heat shield in a limited capacity: i. I don't know much about physics, but could something like this be used as a heat shield of some kind? Good point, it takes a lot more energy to change phase eg.
The phase change will consume energy before heating will occur again. That is the reason why ice water is at 0 celcius until you melt all of the ice, even if the pot it is in is at celcius - you have to put enough energy in to complete the phase c. Parent Share twitter facebook Re:Gets hard when you heat it? Score: 2 by bhima writes: Warm Body??!!
Share twitter facebook Missing some info here Score: 5 , Interesting by Hockney Twang writes: on Saturday September 25, PM It's a solid at those temperatures, what is it at higher temps?
Liquid again? Does it have two melting points? At what temp does it vaporize? Does it freeze at some point below the normal low-end melting point? At 0 degrees Kelvin, it's definitely a solid, somewhere above that, a liquid, then a solid again, then a liquid again, then a vapor?
Share twitter facebook Re:Missing some info here Score: 5 , Informative by dat00ket writes: on Saturday September 25, PM Homepage "At 0 degrees Kelvin, it's definitely a solid" I wouldn't be too sure about that. Bose-Einstein Condensate [wikipedia. But assuming you mean 'near 0 Kelvin', like d00ket pointed out, things get really weird down there. Some substances don't appear to have freezing points, there is no state below 'liquid' And some freeze quite normally, then do another transition way down there where they move back to a liquid like substance.
The substance in the article is interesting, but not completely amazing. Various 'states of matter' are just rules of thumb. I know, it's a trick. The fermionic atoms pair up [colorado. Weird trick, I don't really get it. How are they overlapping enough do that in the first place?
Damn quantum mechanics. But that way leads to madness and people walking though walls after removing a few atoms from their body and the wall. From Haldex [haldex-traction. The unit can be viewed as a hydraulic pump in which the housing and an annular piston are connected to one shaft and a piston actuator is connected to the other.
The two shafts are connected via the wet multi-plate clutch pack, normally unloaded and thus transferring no torque between the shafts. When both shafts are rotating at the same speed, there is no pumping action. When a speed difference occurs, the pumping starts immediately to generate oil flow. It is a piston pump, so there is a virtually instant reaction with no low-speed pumping loss. The oil flows to a clutch piston, compressing the clutch pack and braking the speed difference between the axles.
The oil returns to the reservoir via a controllable valve, which adjusts the oil pressure and the force on the clutch package.
The best option over the above and a common upgrade is the fully-mechanical " Torsen " torque-sensing differential. Quaife [quaife. Plazanet and colleagues prepared a liquid solution containing?
CD , water and 4-methylpyridine 4MP. Placing the solid into my fridge, and again forgetting it for say, 2 or 3 weeks, reduces the solid back into a liquid. Though I havn't personally tried it, I'm fairly certain that if I were to return the liquid back to the oven, and again properly forget about it, that I would again get a solid.
I work in molecular biology. Recently we started doing experiments with so-called Matrigel. This is purified extracellular matrix from mice tumours. It's a natural environment to grow endothelial cells and study the development of blood vessels.
This is by no means a mysterious substance - thousand of labs buy it and use it every day. Well, Matrigel works exactly the same way the substance in the article does. It is fluid around 0, but rapidly freezes at and rapidly becomes solid at room temperature.
And it is fully reversible. This also makes the substance a bitch to manipulate -you pick up with the pipette,and it becomes solid inside the pipette before you can transfer it!
Still, it is amazing to mimic such a behaviour in a simple solution instead than in the tremendous proteins-and-sugars mess that's Matrigel.
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Follow Slashdot on LinkedIn. Roland Piquepaille writes "There are some sure things in life, such as death and taxes. When you are heating a solid, you expect it will melt and when you're boiling water, you're pretty certain that it will turn into vapor. But what about a liquid that becomes solid when it's heated? Of course, it has already been done, for example in the chemical process of polymerization.
But now, PhysicsWeb writes that a team of French physicists has discovered a law-breaking liquid that defies the rules. When you heat it between 45 and 75C, it becomes solid. But the process is fully reversible, and this is a world's premiere. When you decrease the temperature, this solid melts and turns again into a liquid. I'm not sure of the implications of such a phenomenon, but it's fascinating. Read more for essential details. This discussion has been archived. No new comments can be posted.
Full Abbreviated Hidden. More Login. Weird, but cool! Score: 5 , Funny. Share twitter facebook. Re:Weird, but cool! Score: 4 , Insightful. Parent Share twitter facebook. Score: 3 , Interesting. It was a joke. Perhaps you should stop working of your vocabulary and start working on your sense of humor.
Score: 3 , Funny. He's probably just studied some philosophy. Get a clue. Or a PHIL minor. Or something. All of the above. Hehe, "discovering a priori things we weren't aware of" is somewhat of an oxymoron: Websters: a priori [webster. Can darwinism work on software bugs? Score: 3 , Insightful. Afterwards, you probably modified that bit of code slightly otherwise, you could have just made it a function. From the article: However, a reversible transition in which a liquid becomes a solid when heated has never been observed until now emphasis added by poster boaworm wrote: Ever heard of a thing called an "egg" I have in fact Score: 4 , Informative.
Eggs dont turn back to liquid when you cool them It appears that the a CD hydrogen bonds break, resulting in the hydroxyl groups rotating outwards, allowing the formation of a network of bonds between different molecules. Other cyclodextrine and pyridine systems apparently also turn solid on heating and further studies on sol-gel systems are in the process.
Anonymous answered. I think every proteineous liquids become solid on heating like Albumen. As far as I know. But let me know if any other is there. Sea water when we heat it turns into salt Register to unlock all the content on the site. E-mail Address. Physics World Jobs Take the next step in your career and find your perfect job.
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