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Electric Fishes

2014-04-29 00:00:00
科學(xué)大眾(中學(xué)) 2014年6期

魚(yú)能發(fā)電這個(gè)說(shuō)法似乎是令人難以置信的。然而在科學(xué)技術(shù)高度發(fā)達(dá)的今天,科學(xué)家們觀測(cè)到有些魚(yú)發(fā)出來(lái)的電的強(qiáng)度可以點(diǎn)亮小燈泡甚至發(fā)動(dòng)小馬達(dá)。

The idea of a fish being able to generate electricity strong enough to light small bulbs, or even to run an electric motor, is almost unbelievable. But several kinds of fishes are able to do this, and curiously enough, they are not even very closely related. This strange power has been acquired separately, by fishes belonging to very different families.

Perhaps the best know are the Electric Rays or Torpedoes, of which several kinds are found in warm seas. These possess, on each side of the head behind the eyes, a large organ consisting of a number of hexagonal-shaped cells, rather like a honeycomb. The cells are filled with a jell-like substance, and contain a series of flat electric plates. One side, the negative side, of each plate is supplied with very fine nerves, connected with a main nerve coming from a special lobe of the brain. It has been shown that the current passes from the upper, or positive side of the organ, downwards to the negative lower side.

Generally it is necessary to touch the fish in two places, completing a circuit, in order to receive a shock. The strength of this shock depends, of course, on the side of the Torpedo, but newly-born ones, only about two inches across, can be made to light the build of a pocket torch for a few moments, while a fully grown fish gives a shock capable of knocking down a man, and if suitable wires are connected, will operate a small electric motor for several minutes.

麻辣熱詞

1. web shy 網(wǎng)絡(luò)羞澀

很多現(xiàn)代人都喜歡在網(wǎng)上曬自己的個(gè)人生活,但是也有例外,不少人在微信、微博里只是看看,從不評(píng)論,也很少分享個(gè)人圖片和信息,是典型的“潛水一族”。這類(lèi)人在英文中的表達(dá)為“web shy”(網(wǎng)絡(luò)羞澀)。

2. hallyu n. 韓流

韓劇《來(lái)自星星的你》再次在亞洲各國(guó)掀起了強(qiáng)大“韓流”, “hallyu”(韓流)是針對(duì)本世紀(jì)以來(lái)韓國(guó)文化在亞洲其他國(guó)家受到熱捧的現(xiàn)象而造出的英語(yǔ)新詞。

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