B1 中級 13 タグ追加 保存
動画の字幕をクリックしてすぐ単語の意味を調べられます!
単語帳読み込み中…
字幕の修正報告
Big news in the world of tiny structures—scientists may have reached the theoretical limit of
how strong this particular material can get, designing the first ever super-light carbon
nanostructure that's stronger than diamond.
OK, I feel like here at Seeker we talk a lot about carbon nano- stuff.
But what do those words actually mean?
Well, carbon is a famously versatile element in the diversity of structures it can take,
from graphite like in the tip of a pencil to a diamond.
Both are just pure carbon, but with atoms arranged in different patterns.
So carbon nanostructure literally means any arrangement of carbon atoms that results in
something that can be measured on the nanometer scale, and that has novel or improved properties
or functions due to its size: that includes carbon nanotubes, fullerenes, 2D graphene,
carbon nanoparticles, and something called carbon nanohorns, which sounds really fun.
This latest development in the nanoworld of carbon comes from a team that has designed
something called carbon plate-nanolattices.
Under a scanning electron microscope, they look like little cubes.
The math indicated that this structure would be incredibly strong, but the difficulty of
making it meant it had never been done... until now.
This team's success was made possible by a 3D-printing process called two-photon polymerization
direct laser writing, which is quite a mouthful.
This is essentially 3D printing on the level of atoms and photons, which is definitely
the coolest thing I've heard about this week.
The technique focuses a laser inside a droplet of resin that is sensitive to ultraviolet
light.
The droplet is bombarded with two photons at a time, hence the name
that 'prints' the resin into a solid.
The team can use this process to create a particular arrangement of carbon struts and
braces that make the structure uniquely strong and light,  as well as enabling it to be
a "closed-cell" structure.
This has been incredibly difficult to achieve so far in the manufacturing process—usually
these nanostructures have to be constructed around a cylindrical scaffold, resulting in
a shape called "beam nanolattices."
This seemingly small shift from a beam to a plate structure results in a lattice that's
a whopping 639 percent stronger and 522 percent more rigid.
This means the new design approaches the Suquet and 'Hashin-Shtrikman upper bounds,' which
is a fancy way of saying this type of design proved to be just about as strong and tough
as it gets.
Like, we think this tiny carbon nanostructure is the strongest a material this porous can
ever be—and we made it, in the lab, with a LASER!
This is the first time a material that reaches those limits has ever been experimentally
verified.
One of the scientists on this team put it really neatly when they said that at this
size, a structure like this essentially becomes a crystal, reducing its flaws and making it
stronger.
That's why these nanomaterials can be so freaking strong—in this case, stronger than
diamond.
But how can a material so small possibly be of any use on a larger scale?
Well, incredibly strong nanomaterials in general promise great leaps forward in many fields,
from medicine to electronics.
But these carbon plate-nanolattices in particular could transform fields like aerospace engineering
because of their incredible strength while still maintaining a very low density.
Perfect for flying into space!
But there's a long way to go before we see these used in a spacecraft.
If you thought just making one cube was hard, think about scaling that up to industrialized
quantities.
Not an easy task.
This is just the first proof-of-concept for yet another carbon nano wonder material, but
with experiments like these yielding exciting results, we're well on our way to a tiny
and mighty world.
If you want more in carbon advancement, check out this video here, and subscribe to Seeker
for more boundary-pushing materials science.
And fun fact, scientists actually been making nanostructures out of carbon for the past
35-ish years since Kroto, Smalley, and Curl discovered how to do it, and won the Nobel
Prize for it!
If you have other carbon nanostructure news you want us to cover, leave it a comment
down below, and thanks so much for watching.
I'll see ya next time.
コツ:単語をクリックしてすぐ意味を調べられます!

読み込み中…

This Photon-Printed Carbon Is Stronger Than Diamond

13 タグ追加 保存
Summer 2020 年 8 月 7 日 に公開
お勧め動画
  1. 1. クリック一つで単語を検索

    右側のスプリクトの単語をクリックするだけで即座に意味が検索できます。

  2. 2. リピート機能

    クリックするだけで同じフレーズを何回もリピート可能!

  3. 3. ショートカット

    キーボードショートカットを使うことによって勉強の効率を上げることが出来ます。

  4. 4. 字幕の表示/非表示

    日・英のボタンをクリックすることで自由に字幕のオンオフを切り替えられます。

  5. 5. 動画をブログ等でシェア

    コードを貼り付けてVoiceTubeの動画再生プレーヤーをブログ等でシェアすることが出来ます!

  6. 6. 全画面再生

    左側の矢印をクリックすることで全画面で再生できるようになります。

  1. クイズ付き動画

    リスニングクイズに挑戦!

  1. クリックしてメモを表示

  1. UrbanDictionary 俚語字典整合查詢。一般字典查詢不到你滿意的解譯,不妨使用「俚語字典」,或許會讓你有滿意的答案喔