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    当今世界,光学技术广泛应用于医学、军事、工农业生产等领域,其中光学技术成果在改善生态环境、推动农业技术发展等方面起着越来越重要的作用。

    光解油烟——让生命远离伤害

    在现代家庭生活中,厨房油烟具有不容忽视的危害性。为了减少油烟污染,人们发明了抽油烟机,但它仅能收集部分油烟,不能降解有害油烟成分,而且清洗抽油烟机的清洗液排入下水道,还会对环境造成二次污染。光解油烟净化器的问世则改变了这种局面。净化器以特制灯管发出的高能紫外线把油烟分子降解为微小的油脂分子,这些油脂分子一部分生成二氧化碳和水,一部分与氧反应形成微量固态粉末,它们一并被风带走,从而达到清除油脂的目的。此外,高能紫外线还能把异味分子降解为没有气味的物质,也可以杀灭微生物的生物活性,因此可以高效去除油烟中的异味和杀死细菌。净化器具有的①、②和杀菌的作用,大大降低了油烟对人体造成的伤害。

    ③——让室内空气更清新

    净化室内空气的方法很多,其中光触媒空气净化法具有广阔的应用前景。光触媒实际就是光催化剂,在光照条件下其表面能发生氧化还原反应。光触媒主要成分为一种纳米级的二氧化钛活性材料。这种活性材料喷涂于墙面之后可形成一层薄膜,通过吸收阳光中的紫外线发生光催化作用,从而产生活性氧和氢氧基,对空气的有害气体进行降解,并能分解微生物释放出来的毒素,同时还具备除臭、抗污、防霉、自净等功能。光触媒空气净化法最终的反应产物为二氧化碳、水和其他无害物质,不会产生二次污染。在净化过程中光触媒本身也不会发生变化和损耗,因此具有持续作用的优势。

    光学防虫——让农作物免受虫害

    为了保障农产品的质量安全,农业生产环节要减少或不用化学农药,因此需要大力推广物理杀虫技术。灯光诱虫技术是成本最低、用工最少、副作用最小、效果最好的物理防治方法。它利用生物的趋光性诱集并消灭害虫。不同种类的昆虫对不同波段光谱的敏感性不同,如黄光对蚜虫具有较强的诱集力,紫外光对数百种害虫有较强的诱集力。实验证明,在安装了这种新型光源装置的卷心菜种植区内,卷心菜的受害率仅为1/7;而在未安装的种植区内,几乎100%的卷心菜都受到了害虫的侵害。

    植物生长灯——④

    阳光对于植物的意义,主要是通过光合作用来实现的。植物对光的喜好是有选择性的,特殊波段的光能够促进植物的生长。科研人员据此研发了特殊的植物生长灯,用人工方法模拟对植物有促进作用的最佳光谱,增加对植物的照射,促进其生长,从而提高其产量和品质。他们用农用钠灯为草莓施“光学肥料”,延长了大棚草莓的光合作用时间,缩短了生长周期,提高了30%左右的产量,同时增加了草莓的甜度,改善了草莓的色泽。使用绿色高效的“光肥”,是生态农业的一项新举措。

    光学技术不仅用于环境保护和农业生产中,随着科学技术的不断发展,它的应用领域还会更加广泛。

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    There are two great trends on parents bringing up children today.First,children are now praised to an unbelievable degree.As Dorothy Parker once joked,American children aren't raised;they are motivated.Children are constantly told how special they are.The second is that children are honed(磨砺) to an unimaginable degree.Parents spend much more time than in past generations on their children's development.

    These two great trends—greater praise and greater honing—combine in close ways. Parents shower their kids with affection,but it is intermingled with the desire to help their children achieve success.Parents are happy when their child studies hard,practices hard,wins first place,gets into a famous college.

The wolf of conditional love is hidden in these homes.The parents feel they love their children in all circumstances.But the children often think differently.They feel that childhood is a performance—on the athletic field,in school and beyond.The shadowy presence of conditional love produces a fear,the fear that there is no completely safe love.

    Meanwhile,children who are uncertain of their parents' love develop a great hunger for it. This conditional love is1ike an acid that affects children's criteria to make their own decisions about their own colleges,majors and careers.At key decision-points,they unconsciously imagine how their parents will react.

    These children tell their parents those things that will bring praise and hide the parts of their lives that won't. Studies suggest that children who receive conditional love often do better in the short run.They can be model students.But they suffer in the long run. They come to hate their parents.They are so influenced by fear that they become afraid of risk.

    Parents today are less likely to demand obedience(顺从) with explicit rules and lectures.But they are more likely to use love as a tool to exercise control. But parental love is supposed to ignore achievement. It's meant to be an unconditional support -a gift that can not be bought and cannot be earned.