仔细阅读科普知识类第9关

The first bicycles were made of wood. Cycle manufacturers then switched to steel tubes. These days, for high-end bikes where weight is at a premium, they use aluminium alloys (铝合金) or even carbon fibre. But Izhar Gafni, an amateur cyclist who owns a number of such fancy bikes, wonders whether the original inventors had a point. He proposes to go back to using wood—or, rather, a derivative (衍生物) of wood, namely cardboard. Mr. Gafni, who is based in Ahituv, Israel, spent years trying to work out how to make a cardboard bicycle able to support the weight of a human being. The trick is twofold. First, he folds the cardboard—commercial-grade material, made from recycled paper—to increase its strength. Then, once it is folded, he treats the result with a proprietary resin (树脂) that holds it in shape and stiffens it, before cutting it into the form of the component required. A second application of resin renders the component waterproof, and a lick of lacquer (漆) makes it look good. The result, Mr. Gafni claims, is stronger than carbon fibre. The bike's frame, wheels, handlebars and saddle are all made of cardboard in this way, and then fitted together. The tyres—gain harking back to the early days of cycling—are composed of solid rubber, which is recycled from old car tyres. That makes the ride a little harder than if the tyres were pneumatic (充气轮胎的), but means they cannot be punctured. The chain is also made from car-tyre rubber. The pedals are plastic recycled from bottles and the brakes are recycled too, though Mr. Gafni is not yet ready to disclose the details. The finished product weighs 9kg, a bit less than an ordinary bike, and can carry a rider weighing 220kg. Mr. Gafni's target market is the poorer countries of the world. Because manufacturing the cardboard bike will, he reckons, cost $ 9-12 a unit, and his design is far more affordable than a steel-framed bike. But people in rich countries may be interested too. In Tel Aviv, the commercial capital of Mr. Gafni's native land, 2 000 stolen bikes were recently put on display by police, for their owners to claim. If bicycles cost less than the locks that chained them to lampposts, thieves might not think it worthwhile to steal them.

1 What does Izhar Gafni think of the materials bicycles are made of?: A.He believes that materials like wood also have their advantages.
B.He feels the modern materials for bicycles are too fancy.
C.He hopes to develop cheaper high-tech materials for bicycles.
D.He wonders why the original inventors choose wood for bicycles.

本题答案： A B C D

参考答案：A
系统解析：
由题干中的Izhar Gafni定位到原文第一段第四句。推理判断题。由定位句可知，Izhar Gafni想知道最初的发明者是不是有道理。下文也提到，他建议重新使用木材或者纸板来制作自行车。由此推知，A)为正确答案。

2 What effect does the proprietary resin have on the cardboard?: A.It makes the bicycle even lighter.
B.It helps the cardboard to maintain its shape.
C.It makes the cardboard easy to fold.
D.It gives the bicycle a good look.

本题答案： A B C D

参考答案：B
系统解析：
由题干中的proprietary resin定位到第二段第四句。细节辨认题。由定位句可知，Gafni先生对纸板进行了折叠，并用一种专利树脂加以处理，使之成形、固定，因此B)"帮助纸板保持形状"为正确答案。

3 What is the major reason for having solid rubber tyres for the cardboard bicycle?: A.They can help lower the cost.
B.They are environment-friendly.
C.They can ensure the safety of the rider.
D.They are more endurable.

本题答案： A B C D

参考答案：D
系统解析：
由题干中的solid rubber tyres定位到文章第三段最后一句。推理判断题。由定位句可知，用固体橡胶做成的轮胎不容易被刺破，因此D)"它们更耐用"符合题意。

4 What can be learned about the brakes of Mr. Gafni's bicycle?: A.They make use of some car technology.
B.They are made of plastic from recycled bottles.
C.Their details are still unknown to the public.
D.They can bear a weight of 220kg.

本题答案： A B C D

参考答案：C
系统解析：
由题干中的the brakes定位到第四段第二句。细节辨认题。由定位句可知，车闸也是使用了可回收材料，但Gafni先生还不打算将细节进行公开，因此C)正确。

5 What is the competitive advantage of a cardboard bike?: A.It is much lighter than a steel-framed bike.
B.It is cheaper than a steel-framed bike.
C.It has specially designed the anti-theft lock.
D.It can bear a unique look designed by its owner.

本题答案： A B C D

参考答案：B
系统解析：
由题干中的advantage和a cardboard bike定位到最后一段第二句。细节辨认题。由定位句可知，纸板自行车比金属框架自行车要便宜，这是它的一个竞争优势，因此B)正确。