高分子导电的奥秘

时间：2013-08-11 08:44:06

（单词翻译:单击）

For most of us, a modern lifestyle without polymers is unthinkable…if only we knew what they were. The ordinary hardware-store terms we use for them include "plastics, polyethylene（聚乙烯）, epoxy resins¹（环氧树脂）, paints, adhesives², rubber" -- without ever recognizing the physical and chemical structures shared by this highly varied³ -- and talented -- family of engineering materials. Polymers increasingly form key components⁵ of electronic devices, too -- and with its ever-escalating pursuit of high efficiency and low cost, the electronics industry prizes understanding specific behaviors of polymers. The ability of polymers to conduct charge and transport energy is especially appealing.

Now there's help in appreciating the polymer mystique related to the emerging field of molecular⁶ conduction in which films of charge-transporting large molecules⁷ and polymers are used within electronic devices. These include small-scale applications such as light emitting diodes (LED). At the other end of the scale, in cities and across oceans, the polymer polyethylene is the vital insulating component⁴ in the reliable and safe transport of electrical energy by high voltage underground cables.

In work appearing in the current edition of the Journal of Applied⁸ Physics, researchers at the United Kingdom's Bangor University describes how electrical charges may leak away to the ground through its labyrinth⁹ of molecules.

Researchers Thomas J. Lewis and John P. Llewellyn pay particular attention to the nano-scale structure of polyethylene in which crystalline regions are separated by areas known as "amorphous¹⁰ zones." Their novel employment of superexchange and quantum mechanical tunneling of electrons through the amorphous（无定形的） parts of the polymer helps improve understanding of electrical charge conduction.

"These findings could lead not only to improved properties of high voltage cables but also to a wider understanding of polymer semiconductors¹¹ in device applications," said Lewis.

Their investigation¹² shows that the tunneling feature accounts for the majority of the reported high-field charge transport effects in polyethylene.

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1 resins
n.树脂，松香( resin的名词复数 )；合成树脂v.树脂，松香( resin的第三人称单数 )；合成树脂
参考例句：
The resins were used to turn out millions of helmet liners. 用这类树脂生产了成百万只钢盔内衬。来自辞典例句 Cheapness is one of the main attractions of polyester resins. 廉价是聚酯树脂受到欢迎的主要原因之一。来自辞典例句

2 adhesives
黏合剂( adhesive的名词复数 )
参考例句：
These include dyes, adhesives, solvents, detergents, metals, and other foreign materials. 其中包括染料，粘合剂，溶剂，洗涤剂、金属等外界物质。 Preparation, properties and kinds of polyurethane adhesives were described. 综述了聚氨酯胶粘剂的合成、特性和种类。

3 varied
adj.多样的，多变化的
参考例句：
The forms of art are many and varied.艺术的形式是多种多样的。 The hotel has a varied programme of nightly entertainment.宾馆有各种晚间娱乐活动。

4 component
n.组成部分，成分，元件；adj.组成的，合成的
参考例句：
Each component is carefully checked before assembly.每个零件在装配前都经过仔细检查。 Blade and handle are the component parts of a knife.刀身和刀柄是一把刀的组成部分。

5 components
（机器、设备等的）构成要素，零件，成分；成分( component的名词复数 )； [物理化学]组分； [数学]分量；（混合物的）组成部分
参考例句：
the components of a machine 机器部件 Our chemistry teacher often reduces a compound to its components in lab. 在实验室中化学老师常把化合物分解为各种成分。

6 molecular
adj.分子的；克分子的
参考例句：
The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。 For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。

7 molecules
分子( molecule的名词复数 )
参考例句：
The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。 Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

8 applied
adj.应用的；v.应用，适用
参考例句：
She plans to take a course in applied linguistics.她打算学习应用语言学课程。 This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。

9 labyrinth
n.迷宫；难解的事物；迷路
参考例句：
He wandered through the labyrinth of the alleyways.他在迷宫似的小巷中闲逛。 The human mind is a labyrinth.人的心灵是一座迷宫。

10 amorphous
adj.无定形的
参考例句：
There was a weakening of the intermolecular bonds,primarily in the amorphous region of the polymer.分子间键合减弱，尤其在聚合物的无定形区内更为明显。 It is an amorphous colorless or white powder.它是一种无定形的无色或白色粉末。

11 semiconductors
n.半导体( semiconductor的名词复数 )
参考例句：
Crystals may be insulators, semiconductors, or conductors. 晶体可以是绝缘体，半导体，或导体。来自辞典例句 Semiconductors containing such impurities are called p-type semiconductors. 含有这类杂质的半导体叫做P型半导体。来自辞典例句

12 investigation
n.调查，调查研究
参考例句：
In an investigation,a new fact became known, which told against him.在调查中新发现了一件对他不利的事实。 He drew the conclusion by building on his own investigation.他根据自己的调查研究作出结论。