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    Mya Le Thai is a scientist studying at the University of California, Irvine. She recently discovered a process that may result in batteries that last forever. Thai said she had been discouraged that the batteries for her wireless devices degrade. Over time, they fail to charge fully.

    Thai did not like to have keep her wireless laptop connected to an electrical outlet. She decided to do something about that problem.

    At first, she and her team thought about inventing a new battery. But as they experimented, Thai discovered something that might permit lithium-ion(锂离子) batteries to last forever. Lithium-ion batteries power most wireless devices. Over time, the batteries lose the ability to hold a charge. Most of these batteries have a life span of about 7,000 charging cycles before they die.

    One of the reasons lithium-ion batteries degrade is their use of nanowires(纳米线) to carry electricity. Nanowires are extremely thin. A human hair is thousands of times thicker, for example. Nanowires are extremely efficient carriers of electricity, which makes them useful in batteries. But Thai said their thinness also makes them weak. "Nanowires break over time," she said. "That's why they lose capacity."

    But, Thai had a theory: The nanowires might last longer if covered with a material. She and the team tested her theory. The team tried many coverings for the wires. PMMA was one of them. The nanowires were coated with PMMA and cycled through charges 200,000 times. The PMMA coated nanowires showed no evidence of damage. The results suggest that batteries could last forever, without losing charging ability.

    Thai hopes to continue her research to understand why this material works so well and to see if any other material could create better results.

"It's kind of cool," she said. "I'm really glad people are showing interest in my work and not just in the work itself, but also in technology and energy."

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阅读记叙文《雪地里的红棉袄》,完成后面题目。
                                                                                                雪地里的红棉袄
                                                                                                      高吉波
         ①30年前,我8岁。
         ②母亲不在了,一群孩子挤在父亲的脊梁上,讨吃求穿,日子十分凄惶。
         ③一个好心的媒人看着可怜,说家里没个女人,日子少光彩。于是,在那个黄青不接的春天,我大哥牵着一头瘦毛驴拖回了我的嫂子。她年长我15岁,嫁来时,穿着大红的棉袄,头上戴着大红的花,脸上虽有显而易见的菜色,但却洋溢着幸福的笑容。接亲的驴屁股上绑着两袋玉米,哥说是嫂子用彩礼钱换的。
        ④大约那年冬天吧,嫂子生了孩子。家里又多了张嘴,日子显得更加地拮据。我正在长身子的时候,对米饭有一种本能的渴求,但是,每次盛饭,我都悄悄地拖到最后。我知道,大哥是一家的主劳力,嫂嫂一张嘴管着两个人,只有我是一个闲人,所以,能少吃我尽量地少吃。
        ⑤大哥牵挂着我,有一回,大哥趁嫂子不在,悄悄端给我一碗小米粥。嫂子回来时,我已添净了留在碗边和嘴角的米粒。嫂子似乎察觉出了什么,眼圈儿红红的。晚上,嫂子借故支走大哥,说锅里有碗米粥,是留给我的,我揭开锅,却发现里面还掩着两个鸡蛋。
        ⑥我没喝,也没吃。
        ⑦我跑到河里,破冰给侄女洗尿布。
        ⑧“阿九,你太小,洗不净。”嫂子赶来,抱我到河边。她把我红肿的小手拉到她的怀里暖和,然后摸出两个鸡蛋,硬塞到我手里,“还热,吃吧。”
        ⑨那天,风大,雪大。嫂子仍然穿着那件红棉袄,在雪地里像一团火焰,我的心,也随着这团火焰火热火热的。
        ⑩20年前,我18岁。
        ⑪嫂子给我剃了个新头,然后背着行李送我到小镇的车站上。
        ⑫“阿九,咱家你最有出息,外出读书要学会自己疼自己。”她说。临开车的时候,她塞给我一袋东西,我打开一看,是六个鸡蛋。为了给我凑学费,嫂子卖掉了所有的鸡和鸡蛋,这六个鸡蛋,是我硬坚持着留下来给小侄女的。抱着鸡蛋,我无语而泣。
       ⑬那天,风大,雪大。隔着车窗,嫂子跑着向我招手。我觉得是一团火焰在雪地里跳跃,尽管她穿的棉袄是蓝色的。
       ⑭现在,我38岁,号称作家。
        ⑮父亲和大哥已相继随我母亲去了。他们留下的最后一句话都是说给嫂子的:“真有来世,我变把椅子,让你坐着歇歇。”
        ⑯我与嫂子最末的相见,是去年春节携妻带小回老家去。那次,我特意到店里买了最好的蛋糕。嫂子养了一辈子鸡,收了一辈子的鸡蛋,自己,却没有正儿八经地尝过鸡蛋的味道。
        ⑰嫂子捧着蛋糕,眼里有若隐若现的泪花。她没有吃,全给了我那贪吃的儿子。
        ⑱那天,风很大,雪很大。透过玻璃窗,我看见嫂子从屋外抱着柴草进来给我烧炕,我觉得雪地里有一团火焰永不熄灭。虽然她穿的棉袄是黑色的。
        ⑲晚上,嫂子坐在床上纳鞋底,一双鞋底可以到镇上换上两元钱。嫂子不断地纳鞋底,她纳好的鞋底可以摆满好几个炕。“阿九,你腰疼是不是熬夜坐的时间太长?”她说:“都这岁数了,还不会疼自己。”
       ⑳我没说话。我盯着嫂子久看,我突然发现她的眼睛已经深陷下去,像一眼枯井,而且头发竟也全白。但那一刻我跟30年前一样想:嫂子其实是最美的。
       (21)后来,我在日记里写过这样的话:嫂子是弓,我们是箭,弓因箭而弯。
       (22)“我们”,自然也含着我的侄女,她现在在美国攻读博士。(略有删改)