章节大纲

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    A sperm whale's dorsal fin emerges from the water, capturing a moment during whaling.

    Thar she blows!
    ::她被她吹了!

    From the 1700s up to the late 1900s, whalers searched the ocean for the sperm whale.  Whaling was a dangerous occupation – the prey averaged about fifty feet in length.  But when successful, the search was worth it.  One large whale could produce up to 500 gallons of oil, valuable for making candles, ointments, cosmetic creams, and industrial lubricants. In 1988, sperm whales (and other whale species) were placed under international protection because their numbers were diminishing rapidly.  Today, various vegetable oils are used in place of whale oils.
    ::从1700年代到1900年代后期,捕鲸者在海洋中搜寻了精鲸。捕鲸是一个危险的职业 — — 猎物平均长度约为50英尺。 但一旦成功,搜索是值得的。 一只大型鲸鱼可以生产500加仑的油,对制作蜡烛、油膏、化妆品奶油和工业润滑油很有价值。 1988年,香鲸(和其他鲸类)被置于国际保护之下,因为它们的数量正在迅速减少。 如今,各种植物油被用于取代鲸油。

    Waxes
    ::轴轴

    Another category of molecule is waxes.  Waxes are of long-chain fatty acids and long-chain .  Waxes are soft solids with generally low points and are insoluble in water.  Figure shows the structure of cetyl palmitate, a natural wax present in sperm whales.
    ::另一类分子是蜡。 蜡是长链脂肪酸和长链。 蜡是软固体,一般是低点,在水中无法溶解。 图显示了香鲸中的一种天然蜡,即棕榈酸锡的结构。

    Chemical structure of cetyl palmitate, a natural wax found in sperm whales.

    Cetyl palmitate belongs to the category of compounds called waxes. It is derived from a fatty acid that is 15 carbons in length and an alcohol that contains 16 carbon atoms.
    ::Cetyl Palmatate属于称为蜡类的化合物类别,其来源是15个长度碳的脂肪酸和含有16个碳原子的酒精。

    One of the best known natural waxes is beeswax, though many other animals and plants synthesize waxes naturally.  Waxes can be found on leaves of plants and on the skin, hair, or feathers of animals, where they function to keep these structures pliable and waterproof.  Humans take advantage of the protective properties of natural and synthetic waxes in such applications as floor polish and car wax. Other common waxes include jojoba, carnauba, and wool wax, which is also known as lanolin.
    ::最著名的自然蜡之一是蜂蜡,尽管许多其他动物和植物自然合成了蜡。 在植物叶叶和动物的皮肤、毛毛或羽毛上可以找到蜡,这些动物的皮肤、毛毛或羽毛可以保持这些结构的柔软和防水。人类在地板油和汽车蜡等应用中利用自然和合成蜡的保护性。其他常见的蜡包括Jojoba、carnauba和羊毛蜡(也称为拉诺林 ) 。

     

     

    Review
    ::回顾

    1. What is a wax?
      ::什么是蜡?
    2. Name two properties of waxes.
      ::列出蜡的两个属性。
    3. Name a wax found in sperm whales.
      ::命名在鲸鱼精液中发现的蜡。