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二零零六年教材上新扩大了大意上17篇小说,词汇选项,阅读决断, 回顾概况实现句子, 阅读明白, 补全短文, 完型填空各样题型上都有新扩张文章。 理工科类和卫生类新增的稿子更显示专门的学业性。新扩张作品的言语难度和难点考试的场合设置意况在早晚水准上展示了08年课题的出题趋向。

Let's imagine a sculptor building a statue, just chipping away with his chisel. Michelangelo had this elegant way of describing it when he said, "Every block of stone has a statue inside of it, and it's the task of the sculptor to discover it." But what if he worked in the opposite direction? Not from a solid block of stone, but from a pile of dust, somehow gluing millions of these particles together to form a statue.

(难度B/A级/2009年理工科类教材新扩充小说)

I know that's an absurd notion. It's probably impossible. The only way you get a statue from a pile of dust is if the statue built itself -- if somehow we could compel millions of these particles to come together to form the statue.

The Tiniest Electric Motor in the World

Now, as odd as that sounds, that is almost exactly the problem I work on in my lab. I don't build with stone, I build with nanomaterials. They're these just impossibly small, fascinating little objects. They're so small that if this controller was a nanoparticle, a human hair would be the size of this entire room. And they're at the heart of a field we call nanotechnology, which I'm sure we've all heard about, and we've all heard how it is going to change everything.

  1. Scientists recently made public the tiniest electric motor ever built. You could stuff hundreds of them into the period at the end of this sentence. One day a similar engine might power a tiny mechanical doctor that would travel through your body to remove your disease.

  2. The motor works by shuffling(来回运动卡塔尔 atoms(原子卡塔 尔(阿拉伯语:قطر‎ between two molten metal droplets(小滴卡塔尔 in a carbon nanotube(微米管卡塔尔国. One droplet is even smaller than the other. When a small electric current is applied to the droplets, atoms slowly get out of the larger droplet and join the smaller one. The small droplet grows – but never gets as big as the other droplet – and eventually bumps into the large droplet. As they touch, the large droplet rapidly sops up (吸入卡塔尔国the atoms it had previously lost. This quick shift in energy produces a power stroke(重力行程卡塔 尔(阿拉伯语:قطر‎.

  3. The technique exploits the fact that surface tension -- the tendency of atoms or molecules to resist separating -- becomes more important at small scales. Surface tension is the same thing that allows some insects to walk on water.

  4. Although the amount of energy produced is small -- 20 microwatts(百十分之生机勃勃瓦卡塔 尔(英语:State of Qatar) -- it is quite impressive(给人印象深入的卡塔 尔(阿拉伯语:قطر‎in relation to(与...相比卡塔 尔(阿拉伯语:قطر‎ the tiny scale of the motor. The whole setup is less than 200 nanometers on a side, or hundreds of times smaller than the width of a human hair. If it could be scaled up to the size of an automobile engine, it would be 100 million times more powerful than a Toyota CIMA’s 225 horsepower V6 engine.

  5. In 一九八七, Professor Richard 穆勒 and colleagues made the first operating(专业的, 运转的卡塔 尔(英语:State of Qatar) micromotor(微型斯特林发动机卡塔 尔(英语:State of Qatar), which was 100 microns(微米卡塔尔 across, or about the thickness of a human hair. In 二零零零, Zettl's group created the first nanoscale motor. In 二零零五, they built a nanoconveyor(飞米传送带卡塔 尔(阿拉伯语:قطر‎, which moves tiny particles along like cars in a factory.

  6. Nanotechnology(皮米本事卡塔尔国 engineers try to mimic nature, building things atom-by-atom. Among other things, nanomotors could be used in optical circuits to redirect light, a process called optical switching. Futurists envision(预想卡塔尔 a day when nanomachines(微米机器卡塔 尔(阿拉伯语:قطر‎, powered by nanomotors(飞米引擎卡塔尔国, travel inside your body to find disease and repair damaged cells.

When I was a graduate student, it was one of the most exciting times to be working in nanotechnology. There were scientific breakthroughs happening all the time. The conferences were buzzing, there was tons of money pouring in from funding agencies. And the reason is when objects get really small, they're governed by a different set of physics that govern ordinary objects, like the ones we interact with. We call this physics quantum mechanics. And what it tells you is that you can precisely tune their behavior just by making seemingly small changes to them, like adding or removing a handful of atoms, or twisting the material. It's like this ultimate toolkit. You really felt empowered; you felt like you could make anything.

练习:

And we were doing it -- and by we I mean my whole generation of graduate students. We were trying to make blazing fast computers using nanomaterials. We were constructing quantum dots that could one day go in your body and find and fight disease. There were even groups trying to make an elevator to space using carbon nanotubes. You can look that up, that's true. Anyways, we thought it was going to affect all parts of science and technology, from computing to medicine. And I have to admit, I drank all of the Kool-Aid. I mean, every last drop.

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But that was 15 years ago, and -- fantastic science was done, really important work. We've learned a lot. We were never able to translate that science into new technologies -- into technologies that could actually impact people. And the reason is, these nanomaterials -- they're like a double-edged sword. The same thing that makes them so interesting -- their small size -- also makes them impossible to work with. It's literally like trying to build a statue out of a pile of dust. And we just don't have the tools that are small enough to work with them. But even if we did, it wouldn't really matter, because we couldn't one by one place millions of particles together to build a technology. So because of that, all of the promise and all of the excitement has remained just that: promise and excitement. We don't have any disease-fighting nanobots, there's no elevators to space, and the thing that I'm most interested in, no new types of computing.

A An introduction of a Toyota’s 225 horsepower V6 engine.

Now that last one, that's a really important one. We just have come to expect the pace of computing advancements to go on indefinitely. We've built entire economies on this idea. And this pace exists because of our ability to pack more and more devices onto a computer chip. And as those devices get smaller, they get faster, they consume less power and they get cheaper. And it's this convergence that gives us this incredible pace.

B A description of the nanomotor in terms of power and size.

As an example: if I took the room-sized computer that sent three men to the moon and back and somehow compressed it -- compressed the world's greatest computer of its day, so it was the same size as your smartphone -- your actual smartphone, that thing you spent 300 bucks on and just toss out every two years, would blow this thing away. You would not be impressed. It couldn't do anything that your smartphone does. It would be slow, you couldn't put any of your stuff on it, you could possibly get through the first two minutes of a "Walking Dead" episode if you're lucky --

C [u]Surface tension[/u](表面张笑飞卡塔 尔(阿拉伯语:قطر‎.

(Laughter)

D Previous inventions of nanoscale(微米级的卡塔 尔(阿拉伯语:قطر‎ products.

The point is the progress -- it's not gradual. The progress is relentless. It's exponential. It compounds on itself year after year, to the point where if you compare a technology from one generation to the next, they're almost unrecognizable. And we owe it to ourselves to keep this progress going. We want to say the same thing 10, 20, 30 years from now: look what we've done over the last 30 years. Yet we know this progress may not last forever. In fact, the party's kind of winding down. It's like "last call for alcohol," right? If you look under the covers, by many metrics like speed and performance, the progress has already slowed to a halt. So if we want to keep this party going, we have to do what we've always been able to do, and that is to innovate.

E The working principle of the nanomotor.

So our group's role and our group's mission is to innovate by employing carbon nanotubes, because we think that they can provide a path to continue this pace. They are just like they sound. They're tiny, hollow tubes of carbon atoms, and their nanoscale size, that small size, gives rise to these just outstanding electronic properties. And the science tells us if we could employ them in computing, we could see up to a ten times improvement in performance. It's like skipping through several technology generations in just one step.

F Possible fields of application in the future.

So there we have it. We have this really important problem and we have what is basically the ideal solution. The science is screaming at us, "This is what you should be doing to solve your problem." So, all right, let's get started, let's do this. But you just run right back into that double-edged sword. This "ideal solution" contains a material that's impossible to work with. I'd have to arrange billions of them just to make one single computer chip. It's that same conundrum, it's like this undying problem.

钦定的多个段落都并未有明显的段落核心句(二〇〇六年理工科类A/B级回顾轮廓题中多个钦赐段落都未曾明白段落大旨句卡塔 尔(阿拉伯语:قطر‎,考生方可由此通读钦赐段落的不经意来综合出段落核心, 或倚靠一些立竿见影的答题技艺明确段落焦点。以确认段落第4段的段落焦点为例剖析答题技术:

At this point, we said, "Let's just stop. Let's not go down that same road. Let's just figure out what's missing. What are we not dealing with? What are we not doing that needs to be done?" It's like in "The Godfather," right? When Fredo betrays his brother Michael, we all know what needs to be done. Fredo's got to go.

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