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如图是世界上第一个全超导核聚变“人造太阳”实验装置,能模拟太阳产生能量.为了达到聚变所要求的温度,需要用电流产生磁   场,电流的强度非常大,时间长了,线圈就要发热.从这个角度来说,装置不可能长时间运转.为了解决这个问题,人们把最新的超导技术引入到该装置中.

虽然“人造太阳”的奇观在实验室中已经出现,但“人造太阳”所发出的电能在短时间内还不可能进入人们的家中.根据目前世界各国的研究状况,这一梦想最快有可能在50年后实现.“人造太阳”的实验研究具有十分重大的战略意义.在过去的100年中,人类对能源的研究和使用已从化石燃料的单一化结构,发展到以化石能源为主,核能和水能互补的多元格局.但是,石油、煤炭等化石能源不能过度的开采和使用,目前已经商业化的核裂变能又会产生一定的核废料,同时受到原料的限制.

而核聚变能则被认为是无限、清洁、安全的换代新能源.据专家介绍,自然界最容易实现的聚变反应是氢的同位素﹣﹣氘和氚的聚变.氘在地球的海水中藏量丰富,多达40万亿吨,如果全部用于聚变反应,释放出的能量足够人类使用几百亿年,而且反应产物是无放射性污染的氦.这就是为什么世界各国,尤其是发达国家不遗余力,竞相研究、开发核聚能的原因所在.

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    In ancient Egypt, a shopkeeper discovered that he could attract customers to his shop simply by making changes to its environment. Modern businesses have been following his lead, with more tactics(策略).

    One tactic involves where to display the goods. Foe example, stores place fruits and vegetables in the first section. They know that customers who buy the healthy food first will feel happy so that they will buy more junk food(垃圾食品)later in their trip. In department stores, section is generally next to the women's cosmetics(化妆品) section:while the shop assistant is going back to find the right size shoe, bored customers are likely to wander over cosmetics they might want to try later.

    Besides, businesses seek to appeal to customers' senses. Stores notice that the smell of baked goods encourages shopping, they make their own bread each morning and then fan the bread smell into the store throughout the day. Music sells goods, too. Researchers in Britain found that when French music was played, sales of French wine went up.

    When it comes to the selling of houses, businesses also use highly rewarding tactics. They find that customers make decision in the first few second upon walking in the door, and turn it into a business opportunity. A California builder designed the structure of its houses smartly. When entering the house, the customer would see the Pacific Ocean through the windows, and then the poll through an open stairway leading to the lower level. The instant view of water on both levels helped sell these $10 million houses.