考满分 toefl

1 .Listen to part of a lecture in a fabric design class.

听一段织物设计课上的讲座片段。

1 .What are enzymes? You might still have a question about this after doing the assigned reading. Enzymes are really catalysts--chemicals used to get a reaction going. If you think about the human body, the human body's temperature is really not high enough to make reactions happen. So that's why there are enzymes to make certain reactions happen.

酶是什么呢？即便完成了指定阅读，你们可能对此仍有疑问。酶实际上是催化剂，也就是用于促使化学反应发生的化学物质。想想人体，人体的温度其实并不足以让化学反应发生。所以这就是为什么会有酶来促使某些化学反应发生。

1 .If you think about the digestive system, it has enzymes that help break down food. An enzyme in our saliva breaks down carbohydrates, sugars, and starches. And in the stomach and small intestine, we have enzymes that break down proteins and fats, in addition to carbohydrates. These enzymes are substances like lactase. You might have heard of that one. Lactase is the milk enzyme, and it breaks down lactose, the sugar in milk.

想想消化系统，它含有帮助分解食物的酶。我们唾液中的一种酶可以分解碳水化合物、糖和淀粉。在胃和小肠里，我们有除了能分解碳水化合物之外，还能分解蛋白质和脂肪的酶。这些酶包括像乳糖酶这样的物质。你们可能听说过它。乳糖酶是一种存在于牛奶中的酶，它能分解牛奶中的糖分 —— 乳糖。

1 .But today, let's look at the uses of enzymes in our industry. For instance, as I look around the room, I see many of you are wearing faded jeans. Do you know companies use enzymes to fade your jeans? They use an enzyme called cellulase to create that faded denim look, but we didn't always use cellulase. Well, we didn't always have faded jeans either. Back in the day when you bought your jeans, they were a nice, dark blue. It was only after many washings that they would get that faded look. It's only in the 1970s that companies realized there was a market for jeans that already looked faded. So companies started pre-washing their jeans.

但今天，我们来看看酶在工业中的应用。比如说，我环顾教室，看到你们很多人都穿着褪色牛仔裤。你们知道吗，公司会用酶来让牛仔裤褪色。他们使用一种叫做纤维素酶的酶，来打造那种褪色牛仔布的外观，但我们并非一直都用纤维素酶。其实，我们也不是一直都有褪色牛仔裤。过去，当你买牛仔裤的时候，它们是好看的深蓝色。只有经过多次洗涤后，它们才会呈现出褪色的样子。直到 20 世纪 70 年代，公司才意识到那种看起来已经褪色的牛仔裤有市场。于是，公司开始对牛仔裤进行预洗处理。

1 .Anyway, in the 1970s and 80s, pumice stones were used in a process called stone washing. What would happen? The textile companies would put pumice stones and oh, what is pumice stone? It's a volcanic stone. It's very light. It actually floats in water, but rough. And it's ground up and used in cleaning products like heavy duty hand soaps. So, these pumice stones would then, as I said, be put into a big washing machine and the jeans would be washed with these stones. Well, as you can imagine, when the process was finished, the washing machine was just about worn out. And the jeans would look faded, but also kind of worn out too, because the pumice stones would have abraded some areas more than other areas. Other things that would happen is the buttons on denim jackets or the rivets on the pockets would have a worn finish. But you want your buttons to be shiny and you want the rivets to look shiny too, right? Well, so that process didn't work very well.

不管怎样，在 20 世纪 70 年代和 80 年代，浮石被用于一种叫做石洗的工艺中。具体是怎样的呢？纺织公司会使用浮石，哦，浮石是什么呢？它是一种火山石。质地很轻，实际上能漂浮在水面上，但表面粗糙。它被磨碎后用于像强力洗手液这样的清洁产品中。所以，就像我说的，这些浮石会被放进大型洗衣机里，和牛仔裤一起洗涤。可以想象，这个过程结束后，洗衣机几乎都要报废了。而且牛仔裤看起来褪色了，但也有点破旧，因为浮石对牛仔裤某些部位的磨损程度比其他部位更严重。另外，牛仔夹克上的纽扣或口袋上的铆钉会有磨损的痕迹。但你们肯定希望纽扣和铆钉都闪闪发亮，对吧？所以，这个工艺效果不太好。

1 .There was another problem, but I'll get to that in a minute. Next, the textile industry moved to acid washing. They used acidic bleach, something stronger than you'd use at home. The bleach would break down the fibers and make the dye fade. You can imagine the damage here. Employees were exposed to acid, and it was not an environmentally safe process. The Environmental Protection Agency, a government agency, would monitor the wastewater that came from the company. And when they found this acid and the stones in a… yes, this is that other problem with stone washing I mentioned when they found these things in the wastewater that was not good because the agency would enforce anti-pollution laws and require the company to pay to clean up the water. So that added to the company's expenses and the cost of the jeans went up.

还有另一个问题，我稍后再说。接下来，纺织行业采用了酸洗工艺。他们使用酸性漂白剂，比我们在家用的更强效。这种漂白剂会分解纤维，使染料褪色。大家可以想象其中的危害。员工会接触到酸，而且这不是一个环保的工艺。政府机构环境保护署会监测公司排放的废水。当他们在废水中发现这种酸和（之前石洗工艺中的）石头时…… 没错，这就是我提到的石洗工艺的另一个问题。发现这些物质是不好的，因为环保署会执行反污染法律，要求公司支付净化废水的费用。这就增加了公司的开支，牛仔裤的成本也随之上升。

1 .Finally, in 1989, the textile industry in Europe discovered what they called bio stone. That's the name they gave to the process of using cellulase is to fade denim. Cellulase is the enzyme that breaks down cellulose, just like lactase breaks down lactose. Jeans are made of denim, a type of cotton fabric, and cotton, being a plant, contains cellulose. And that's why they use cellulase. It's still a washing process just using cellulase instead of stones or acid. Using the cellulase creates more even and consistent finish on the denim without streaks or blotches, like you get in the other processes. And it's gentler. It doesn't wear out the denim that much. So you have a nice looking pair of pants that doesn't cost the company a lot of money to make. Also, cellulase treatments are less polluting than either stone washing or acid washing. At least according to manufacturers, another nice benefit. Don't you think?

最后，在 1989 年，欧洲的纺织行业发现了他们称之为 “生物石洗” 的工艺。这其实就是使用纤维素酶让牛仔布褪色的工艺名称。纤维素酶是一种能分解纤维素的酶，就像乳糖酶分解乳糖一样。牛仔裤是由牛仔布制成的，牛仔布是一种棉织物，而棉花作为一种植物，含有纤维素。这就是他们使用纤维素酶的原因。这仍然是一种洗涤工艺，只不过用纤维素酶代替了石头或酸。使用纤维素酶能让牛仔布的表面更加均匀一致，不会出现像其他工艺中那样的条纹或色斑。而且这种方法更温和，不会过度磨损牛仔布。这样一来，公司就能生产出好看的牛仔裤，且生产成本不高。此外，据制造商称，纤维素酶处理工艺比石洗或酸洗的污染更小。这又是一个不错的优点，你们不觉得吗？