These are of two varieties, known as single and double bonds.

化学键有两种，单键和键。

You see, most of these double bonds are in a configuration known as " cis bonds" , but hydrogenation often flips them into something called a " trans configuration" .

你看，大多数键都是“顺式结构”的，但是氢化经常会把它们翻转成“反式构”。

Unsaturated fats, on the other hand, contain double bonds that create an irregular kink in their structure.

相反，非饱和以键以键不规则地连接在一起。

The molecule itself is a diterpene, a kind of carbon-and-hydrogen molecule with lots of double bonds.

这个分子本身是二萜，是一种有很多键的碳氢分子。

These are fats that have double bonds AND stack well...in fact, they stack even better than saturated fats AND our biochemical systems aren't designed to break them down AND they interact badly with cholesterol.

这些脂肪均有链且易于堆积......事实上，它们比饱和脂肪更容易堆积。而我们的生物化学系统并不是专门为分解它们而设计的，而且它们与胆固醇不能相互作用。

The carbons double bond with each other so that fewer hydrogen can fit and we call this unsaturated fat.

个碳原子之间都有键连接，这样氢很难嵌入碳原子之间。我们称这种脂肪为不饱和脂肪。

And that double bond can either lock the chain into a kink or lock it straight.

而且链可以将链固定成一个结或是直线。

Those rings and double bonds don't give PET much flexibility, so the polymers tend to pack closely together, and are harder to melt.

那些环和键无法给 PET 太多的灵活性，所以聚合物会被紧密地聚合在一起，更难被熔化。

Each double bond means two fewer hydrogens.

个链意味着少两个氢原子。

And If the double bond is just before the third carbon from the end, we call that an omega three fatty acid and they seem to have a wide range of benefits.

如果链恰好在倒数第三个碳原子前面，我们称之为欧米伽-3脂肪酸，它们似乎有很多益处。

Corn oil, for example, is made up of lipids with lots of double bonds, also known as polyunsaturated fats.

例如，玉米油是由许多键的脂类组成的，这类物质也叫作多元不饱和脂肪。

Remember there are two types of bonds in double bonds.

请记住， 键中有两种类的键。

And the reason that these are bent is because they have a double bond.

这些分子之所以弯曲，是因为它们含有一个键。

They have this chemical structure that involves having double bonds in it.

它们具有这种化学结构，其中包含键。

Single bonds like this are going to be different than double bonds like this.

像这样的单一债券将不同于像这样的重债券。

If I look at one of these molecules of acetone here and I focus in on the carbon that's double bonded to the oxygen, I know that oxygen is more electronegative than carbon.

如果我在这里观察其中一个丙酮分子， 并关注与氧键结合的碳，我就会知道氧比碳更具电负性。

And you can also form really strong double or even triple bonds with carbon because of the way that the electrons are set up.

由于电子的排列方式，碳还能形成极为牢固的键甚至三键。

The chains are held together by bonds between the carbon atoms. These are of two varieties known as single and double bonds.

这些链通过碳原子之间的键连接在一起。这些键有两种类，分别是单键和键。

But because it's these long chains that are not branched at all and they are, um, they don't have any double bonds.

但因为这些是长链，没有任何分支，并且它们没有键。

In nature, a double bond in a fat chain almost always locks it into a kink.

事实上，脂肪链中的链几乎都是将链固定成一个结。