英語的優美文摘

關於英語的優美文摘，大家有時間可以看看哦，小編今天給大家整理了英語的文摘，只要我們認真的學習這樣纔可以快速的提高成績，所以同學們快點學習起來吧，有需要的可以收藏起來哦

　　神奇的發光色彩?

A MagicAl Glow?

神奇的發光色彩?

Have you ever wondered why fluorescent colors, like you see in highlighters or clothing dyes, for instance, seem so much brighter than other colors?

你想知道爲什麼熒光色，譬如你從熒光筆或服裝染料上看到的顏色，似乎比別的顏色更鮮亮嗎?

It’s because they seem to reflect More light than they receive! It may sound like a magic trick, but it makes sense if you think about the fact that the light you can see is only a small section of the larger spectrum of energy all around you.

原因是這些顏色反射的光線比吸收的光線要多。這可能聽起來像個魔術，但是如果你想到這樣一個事實，即可見光只是你周圍更大光譜能量中的一小部分，那這就合理了。

Regular, non-fluorescent colors appear to our eyes when objects absorb some wavelengths of light, and reflect others. For example, a yellow pencil looks yellow because its paint reflects the wavelength of yellow light, and absorbs the other wavelengths. Fluorescent colors also reflect or absorb colors in the visible spectrum, but that extra glow in fluorescent colors comes from energy we humans don’t see, ultraviolet light.

當物體吸收一些波段的光並反射其他光，我們就能看見一般的非熒光色。例如，黃色彩筆之所以看起來是黃色是因爲該種顏料反射黃色光波，並且吸收其他波段的光。熒光色也反射或吸收了光譜中的可見光，但是熒光色額外的光來自於人眼看不到的能量，紫外光。

Ultraviolet light, or UV, is just beyond visible violet in the spectrum. Its wavelength is too short to be visible to the naked eye, but you see it working when fluorescent colors glow! Regular dyes just absorb UV along with all the other wavelengths they don’t reflect, so you don’t see any evidence of it.

紫外光，或稱作UV，頻率恰好在可見紫光之外。紫外光的波長太短以至於無法用肉眼看到，但是熒光色發光的時候你就能看到它起的效果!一般的染料只是吸收紫外光和所有其他不反射的光，所以你看不到紫外光的存在。

But, fluorescent dyes contain substances that respond to UV. Some of the molecules in these fluorescent dyes are excited by UV energy, and afterwards, as the energy level within these molecules decreases, they release part of that extra energy as visible light.

但是，熒光染料含有對UV起反應的物質。這些熒光染料中的一些分子被UV的能量激活，然後隨着這些分子的能量水平降低，它們就會以可見光的形式釋放出一部分額外的能量。

So fluorescent dyes turn invisible energy into visible light, and that’s how the magic trick works! They don’t reflect more energy than they receive, but they do reflect more visible light, converted from parts of the spectrum we can’t see.

所以熒光染料把不可見的能量轉換成了可見光，這就是魔術的奧妙所在!不是它們反射出的能量比接收的多，而是反射出了更多的可見光，這些多出來的可見光是從我們看不到的波段轉換來的。

　　什麼是條件反射?

What Are Reflexes?

什麼是條件反射?

If you’ve ever blinked at a sudden light, jerked your hand away from something hot, or jumped at a loud noise, then you know that these are not actions we consciously plan. Rather, they happen involuntarily.

如果你曾因爲突如其來的燈光眨眼，碰到燙的東西立刻把手縮回來，或是聽到很響的聲音嚇了一跳，你會發現這些動作並非我們有意識地計劃過的，而是不由自主發生的。

Such sudden, unconscious movements are a kind of simple neural activity known as a reflex.

這些突然、無意識的動作是一種簡單的神經活動，我們稱之爲條件反射。

A deliberate action, such as raising a spoon to the mouth, involves consciousness. We decide to raise the spoon, then we do it. Most reflexes, however, do not involve the brain; they are fast, involuntary responses that travel over what is known as a reflex arc. A reflex arc consists of a stimulus, for example extreme heat, which creates an impulse that travels along sensory nerves and neurons to the spinal cord.

有意的行爲總是包含着意識的參與，比如要把一個勺子送到嘴邊，我們先決定拿起勺子，然後再做這個動作。但大部分的條件反射都與大腦無關，它們是快速、無意 識的反應，這種反應沿着我們所熟知的反射弧傳遞。反射弧包括某種刺激，比如人在極高的溫度下會產生一種神經衝動，這種神經衝動會沿着感覺神經和神經元傳 遞，最後到達脊髓。

Once it reaches the spinal cord, the impulse is routed speedily back to the muscle originally stimulated. This process occurs almost instantaneously, before we’ve even had time to consciously register that the reflex has happened.

一旦到達脊髓，神經衝動便會迅速沿原路返回至最初受到刺激的肌肉。整個過程幾乎是在瞬間完成的，甚至在我們有時間意識到之前，條件反射就已經發生了。

Although a reflex is automatic, it can change over time, depending on the regularity of the stimulus. If a stimulus is repeated continuously, the reflex first undergoes sensitization, meaning that it increases in response.

雖然條件反射是自發形成的，但它會隨着時間發生變化，這要取決於刺激發生的頻率。如果某種刺激不斷地重複，條件反射最開始會對這種刺激變得敏感，換句話說，條件反射的反應次數會增加。

But if the stimulus is repeated beyond a certain point, the reflex begins to decrease until it disappears. In other words, you can tame a reflex by, for instance, hearing a sudden loud noise repeatedly until you stop jumping.

但如果這種刺激超過了某個臨界點時，條件反射次數就會開始減少直至消失。換句話說，條件反射是可以克服的，比如，反覆聽突如其來的巨響，直到你不會被嚇一跳爲止。