首页
登录
职称英语
The first bicycles were made of wood. Cycle manufacturers then switched to
The first bicycles were made of wood. Cycle manufacturers then switched to
游客
2024-01-20
37
管理
问题
The first bicycles were made of wood. Cycle manufacturers then switched to steel tubes. These days, for high-end bikes where weight is a priority, 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—again 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. [br] What can be learned about the brakes of Mr. Gafni’s bicycle?
选项
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.
答案
C
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,车闸也使用了可回收材料。但加夫尼先生还不打算将细节进行公开,因此C)“它们的细节仍不为公众所知”为正确答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3380181.html
相关试题推荐
[originaltext][3]Medicalresearchershaveaccusedthemanufacturersofbaby
Thefirstbicyclesweremadeofwood.Cyclemanufacturersthenswitchedto
Thefirstbicyclesweremadeofwood.Cyclemanufacturersthenswitchedto
Thirtyyearsago,mostteenagershadbicycles,butnowtheyarecomparativel
Thirtyyearsago,mostteenagershadbicycles,butnowtheyarecomparativel
Thirtyyearsago,mostteenagershadbicycles,butnowtheyarecomparativel
Thirtyyearsago,mostteenagershadbicycles,butnowtheyarecomparativel
Thirtyyearsago,mostteenagershadbicycles,butnowtheyarecomparativel
Thirtyyearsago,mostteenagershadbicycles,butnowtheyarecomparativel
Thirtyyearsago,mostteenagershadbicycles,butnowtheyarecomparativel
随机试题
Manyconsumeritemsarebeingredesignedaccordingtothenewstandardwhowill
Manythingsaboutlanguageareamystery,andmanywillalwaysremainso.Bu
A.龈炎 B.咬合痛 C.自发性痛 D.过敏性痛 E.修复体松动牙体缺损
胎盘早剥那项是错误的:()A、胎盘早剥是指在子宫下段的胎盘发生早期剥离而引起
防己黄芪汤与当归拈痛汤的组成药物中均含有A.白术、防风 B.防风、当归 C.
关于测绘人员调离或退休后,其测绘作业证处理的做法,错误的是( )。A.收回调离
力F1、F2共线如图所示,且F1=2F2,方向相反,其合力FR可表示为:
梗阻性黄疸主要表现为 A.丙氨酸转移酶增髙B.碱性磷酸酶增高C.MAO增高
小麦进口实行_,出口实行。 A.关税配额管理;出口配额许可证管理 B.进口
下列中可以降低输血过敏反应发生率的是A.选用一次性输血器 B.选用洗涤红细胞
最新回复
(
0
)