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  • Fluids are a necessary part of everyday life.

    液體是日常生活中的一個必要部分。

  • After all, without water you couldn’t live, and without chocolate syrup, well, what would

    畢竟,沒有水你就無法生存,而沒有巧克力糖漿,那麼,什麼會

  • be the point?

    是什麼意思?

  • But have you ever noticed that not all liquids behave the same?

    但你有沒有注意到,並不是所有的液體都表現得一樣?

  • In fact, some of them do some pretty bewildering stuff under the right circumstances, and even

    事實上,他們中的一些人在適當的情況下會做一些相當令人困惑的事情,甚至是

  • after decades of research scientists are no closer to understanding why.

    經過幾十年的研究,科學家們並沒有更接近於瞭解原因。

  • One question about strange fluids may have finally been answered thanks to some glass

    關於奇怪液體的一個問題可能終於得到了答案,這要感謝一些玻璃

  • beads and—I always love saying thislaser beams.

    珠子和我總是喜歡說這個--激光束。

  • All liquids that we encounter in the real world can be boiled down to one of two kinds.

    我們在現實世界中遇到的所有液體都可以歸結為兩種之一。

  • Theyre either Newtonian, or non-Newtonian.

    它們要麼是牛頓的,要麼是非牛頓的。

  • Newtonian fluids are pretty easy to grasp.

    牛頓流體是相當容易掌握的。

  • I mean, not literally in some cases—a Newtonian fluid like water would squirt right out of

    我的意思是,在某些情況下不是字面上的,像水這樣的牛頓流體會直接噴出。

  • your hand.

    你的手。

  • But chocolate syrup is also Newtonian even though it would slowly dribble out of your

    但巧克力糖漿也是牛頓式的,儘管它會慢慢地從你的身體裡滴出來。

  • hand, maybe as you frantically lick your palm to get as much of that rich goodness before

    掌心,也許當你瘋狂地舔著你的手掌,以獲得儘可能多的那份豐富的美味之前

  • it drips away.

    滴水不漏。

  • It's not just me, right?

    不僅僅是我,對嗎?

  • Uh, anyway.

    呃,無論如何。

  • In other words, chocolate syrup is much more viscous than water.

    換句話說,巧克力糖漿的粘性比水大得多。

  • Viscosity is a measure of a fluid’s resistance to flow.

    粘度是衡量流體對流動的阻力。

  • It’s basically the friction between molecules in a fluid.

    它基本上是流體中分子之間的摩擦。

  • The higher the viscosity, the slower the flow.

    粘度越高,流動越慢。

  • A Newtonian fluid obeys Newton's Law of Viscosity which means its viscosity is constant.

    牛頓流體遵守牛頓粘度定律,這意味著其粘度是恆定的。

  • It doesn’t change when a force is applied to it.

    當一個力施加在它身上時,它不會改變。

  • Non-Newtonian fluids, on the other, less sticky hand, do change their viscositywhich can

    非牛頓流體,在另一方面,不那麼粘稠,確實改變了它們的粘度......這可以

  • lead to some pretty zany shenanigans.

    導致了一些相當瘋狂的惡作劇。

  • There are different sub-categories of non-Newtonian fluids depending on how their viscosity changes.

    非牛頓流體有不同的子類別,這取決於其粘度的變化方式。

  • There are dilatants whose viscosity increases as force is applied.

    有一些稀釋劑的粘度會隨著力的作用而增加。

  • Examples of dilatants include quicksand, silly putty, and the cornstarch-water mixture known

    稀釋劑的例子包括流沙、傻子膩子和已知的玉米澱粉-水混合物。

  • to 1st grade classrooms as oobleck.

    在一年級的教室裡,有一種叫做 "奧布拉克 "的東西。

  • The tiny corn starch particles in oobleck can flow freely with the water molecules if

    泡泡糖中的微小玉米澱粉顆粒可以與水分子自由流動,如果

  • you gently dip your fingers in, but give it a good smack and the cornstarch locks up,

    你可以用手指輕輕地蘸一下,但只要輕輕一拍,玉米澱粉就會被鎖住。

  • giving oobleck a surprisingly solid character.

    賦予橡皮泥一個令人驚訝的堅實性格。

  • You could straight up run across a swimming pool if you dumped enough cornstarch in it.

    如果你在游泳池中傾倒足夠的玉米澱粉,你可以直接跑過游泳池。

  • But, there are vandalism laws so, y’knowdon’t.

    但是,有破壞性的法律,所以,你知道......不要。

  • Some fluids get more viscous when force is applied, but the opposite can also be true.

    有些液體在受力時變得更加粘稠,但也可能是相反的情況。

  • Ketchup is in a category of non-Newtonian fluids called pseudoplastics.

    番茄醬屬於非牛頓流體的一個類別,被稱為假塑性流體。

  • When no force is applied, it just sits there.

    當沒有施力時,它只是坐在那裡。

  • Not doing anything.

    不做任何事情。

  • But when you give the back of the bottle a whack the viscosity decreases and the ketchup

    但當你在瓶背上拍打一下時,粘度就會下降,番茄醬就會

  • comes out.

    出來了。

  • Inside the sauce at a molecular level what’s happening is long chains of atoms called polymers

    在醬汁內部,在分子水準上,正在發生的是稱為聚合物的原子長鏈。

  • get tangled together and hold fast, but when smacked or shaken, they stretch out and align,

    糾纏在一起,緊緊抓住不放,但當抽打或搖晃時,它們就會伸展開來,保持一致。

  • allowing the gooey red paste to slide around, hopefully onto your french fries but probably

    讓粘稠的紅色糊狀物滑來滑去,希望能滑到你的炸薯條上,但可能是

  • on your pants too.

    在你的褲子上也是如此。

  • Still there are many more weird non-Newtonian behaviors scientists don’t have answers

    仍然有許多奇怪的非牛頓行為科學家沒有答案

  • for.

    為。

  • They may have just solved one riddle that’s stood for over 50 years.

    他們可能剛剛解決了一個存在了50多年的謎題。

  • The problem was first noticed in the 1960s when engineers were attempting to extract

    這個問題第一次被注意到是在20世紀60年代,當時工程師們正試圖提取

  • oil from the ground with fluids that contained long-chain polymers.

    用含有長鏈聚合物的液體從地下開採石油。

  • Pumping these so-calledpusher fluidsinto the ground below a certain rate worked

    將這些所謂的 "推注液 "泵入地下,低於一定的速度,就會產生效果

  • fine, but pumping them faster would cause them to become much more viscous, like oobleck.

    很好,但是抽得更快會使它們變得更加粘稠,就像橡皮泥一樣。

  • The fluids would only behave this way when flowing through the microscopic spaces between

    液體只有在流經兩邊的微觀空間時才會有這樣的表現。

  • soil; when not confined to the twisty windy paths in a porous medium, the fluidsviscosity

    土壤;當不侷限於多孔介質中的曲折風路時,流體的粘度

  • would actually drop as more force is applied, like ketchup.

    實際上會隨著施加更多的力而下降,就像番茄醬。

  • For a while, scientists thought maybe the polymers were clogging up the pores in the

    有一段時間,科學家們認為可能是聚合物堵塞了孔隙。

  • soil, but that couldn’t explain how the fluids flowed easily when the flow rate dropped

    土壤,但這並不能解釋當流速下降時,液體是如何輕鬆流動的。

  • again.

    再次。

  • It wasn’t until a new study was published in late 2021 that scientists think they might

    直到2021年底發表的一項新研究,科學家認為他們可能

  • have cracked it.

    已經破解了它。

  • Part of the problem theyve had is soil and other porous media aren’t see-through,

    他們遇到的部分問題是土壤和其他多孔介質是不透明的。

  • so it’s hard to tell what’s going on down there.

    所以很難說下面發生了什麼。

  • To solve this they created a custom medium out of glass beads.

    為了解決這個問題,他們用玻璃珠創造了一種定製介質。

  • And they concocted a polymer solution with the same refractive index of the glass, meaning

    他們調製了一種聚合物溶液,其折射率與玻璃相同,這意味著

  • the liquid and solid would both bend light exactly the same way.

    液體和固體都會以完全相同的方式彎曲光線。

  • To see the windy paths fluids would follow in the spaces between the beads, the researchers

    為了看到液體在珠子之間的空間裡的風行路徑,研究人員

  • added a red dye to the solution that would give off a certain wavelength of light when

    在溶液中加入一種紅色染料,當它發出某種波長的光時,就會發出某種波長的光。

  • hit with a laser.

    被脈衝光擊中。

  • To visualize how the fluid was moving, they added tracer particles that would emit

    為了直觀地看到流體是如何移動的,他們添加了會發出 "嗡嗡 "聲的示蹤粒子。

  • a different color when excited by another laser.

    當被另一個激光器激發時,會出現不同的顏色。

  • With this extremely complicated setup in place they observed the fluid flowing at different

    有了這個極其複雜的裝置,他們觀察到流體以不同的速度流動。

  • rates and found that the long polymers in it started tumbling around as the fluid moved

    速率,並發現其中的長聚合物在流體移動時開始翻滾。

  • faster.

    更快。

  • This movement pushed on other nearby molecules in the liquid and created a phenomenon called

    這種運動推動了液體中其他附近的分子,併產生了一種稱為

  • elastic turbulence,” creating eddies and slowing the whole fluid down.

    "彈性湍流",產生渦流,使整個流體速度減慢。

  • The researchers think this new understanding of why pusher fluids suddenly become so viscous

    研究人員認為,這種對推注液為何突然變得如此粘稠的新認識

  • could be useful for purifying groundwater.

    可能對淨化地下水有幫助。

  • It may aid in the development of new polymer-containing solutions that can force water through rocks,

    它可能有助於開發能夠迫使水穿過岩石的新的含聚合物溶液。

  • trapping contaminants in the process.

    在這個過程中捕獲汙染物。

  • But there’s more work to be done because elastic turbulence itself isn’t fully understood.

    但是還有更多的工作要做,因為彈性湍流本身並沒有被完全理解。

  • Maybe thatll be the next riddle solved.

    也許這將是下一個解開的謎題。

  • Or maybe first well get an answer for why people like ketchup on scrambled eggs.

    或者首先我們會得到一個答案,為什麼人們喜歡在炒蛋上加番茄醬。

  • Granted that has nothing to do with its non-Newtonian properties but it’s still

    儘管這與它的非牛頓特性無關,但它仍然是

  • something I just can’t wrap my head around.

    我只是無法理解的事情。

  • Thanks so much for watching, don't forget to subscribe, and I'll see you for the next Seeker.

    非常感謝你的觀看,別忘了訂閱,我們下期《探索者》再見。

Fluids are a necessary part of everyday life.

液體是日常生活中的一個必要部分。

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