Question

    Disease spread in many ways. An infected person can cough or sneeze on someone nearby, or they can spread germs through a handshake. But sometimes we pick up germs indirectly. A sick person might leave behind bacteria or viruses when they touch a door handle, for example. But what if those surfaces could clean themselves?

Two teenagers from Hong Kong asked themselves the same question. Now they’ve developed a door handle that can kill germs on contact.

The idea is simple. Every time the door is opened, the movement creates power that starts a germ-killing reaction on the handle. In lab tests, their system killed about 99.8 percent of the germs that they spread onto lab dishes covered with their material.

Research by others has shown that door handles in public areas are often home to lots of bacteria and viruses, notes 17-year-old Sum Ming(“Simon”）Wong. He and schoolmate Kin Pong ( Michael ) Li, 18, wanted to design a covering for door handles that would kill germs.

After doing some research, they learned that a mineral called titanium dioxide(二氧化钛）is known to kill bacteria. It’s already used in many products, from paints to desserts. To make their covering, the teenagers made the mineral into a very fine powder.

Titanium dioxide kills bacteria best when lit by ultraviolet(紫外线的）light, says Simon. UV light is found in sunlight. But UV light does not naturally shine on indoor handles or any used at night, so the teenagers light their door handle from within.

To make sure the light reaches the coated surface, the teenagers made their door handle out of clear glass, Each end fits into a bracket (托架).Inside one of the brackets is a strong light-emitting diode(LED). From it comes UV light.

And here’s the interesting part: The power that makes the UV light shine comes from opening and closing the door. The power from the door is then carried by wire to the LED inside the door handle.

The door handle system, Michael and Simon say, might cost no more than about $13 (about 81 yuan) to build.

1.The ways diseases spread are mentioned at the beginning of the text to .

A.demonstrate how most diseases are spread indirectly

B.remind readers of the importance of cleaning their hands

C.explain how to kill bacteria or viruses effectively

D.help to describe a new invention that prevents diseases from spreading

2.Michael and Simon’s door handle      .

A.is too expensive for ordinary families

B.is powered by the movement of its users

C.works better at night than in the daytime

D.is made of a metal that can take in UV light

3.The LED is placed inside the brackets to     .

A.supply enough power to the handle system

B.produce titanium dioxide to kill bacteria

C.provide UV light to help titanium dioxide work better

D.direct the UV light in sunlight to the coated surface

4.What is the author's attitude toward Michael and Simon s door handle system?

A.Cautious B.Critical

C.Enthusiastic D.Disappointed

Answer

1.D

2.B

3.C

4.C

【解析】

本文是科技说明文，介绍两位香港青少年发明自动消毒手柄的文章。

1.推理判断题。第一段“Disease spread in many ways. An infected person can cough or sneeze on someone nearby, or they can spread germs through a handshake. But sometimes we pick up germs indirectly. A sick person might leave behind bacteria or viruses when they touch a door handle, for example. But what if those surfaces could clean themselves?” 疾病以多种方式传播。感染者可以通过对附近的人咳嗽或打喷嚏，也可以通过握手传播细菌。但有时我们会间接地感染细菌。例如，一个生病的人可能会在接触门把手时留下细菌或病毒。但是如果门把手的表面可以自我清洁呢？然后在第二段“Two teenagers from Hong Kong asked themselves the same question. Now they’ve developed a door handle that can kill germs on contact.” 来自香港的两名青少年也问了自己同样的问题。现在他们发明了一种门把手，可以杀死接触的细菌。由此可知，开篇主要是引入为什么要发明这个自动消毒手柄，即帮助描述防止疾病传播的新发明---自动消毒手柄。故选D。

2.推理判断题。第三段“The idea is simple: Every time the door is opened, the movement creates power that starts a germ-killing reaction on the handle.” 想法很简单。每次门被打开时，这种运动都会产生能量，导致门把手产生杀死细菌的反应。由此可推断出迈克尔和西蒙设计的门把手是由推门的人的移动来驱动的。分析选项可知B项（由使用门的人的移动提供动力）符合题意，故选B。

3.推理判断题。根据第六段“Titanium dioxide kills bacteria best when lit by ultraviolet light, says Simon. UV light is found in sunlight. But UV light does not naturally shine on indoor handles or any used at night, so the teenagers light their door handle from within.” 二氧化钛在紫外线照射下最能杀灭细菌。阳光中有紫外线。西蒙说。紫外线是在阳光中发现的。但是紫外线不会自然地照射到室内把手或任何夜间使用的把手上，所以这两个青少年想从室内照亮他们的门把手。第七段“To make sure the light reaches the coated surface, the teenagers made their door handle out of clear glass, Each end fits into a bracket (托架) Inside one of the brackets is a strong light-emitting diode (LED). From it comes UV light.” 为了确保光线到达涂有粉末的表面，这两个青少年用透明玻璃制造出门把手，两端各配备一个支架。 其中一个支架内是一个强大的发光二极管(LED)。它发出紫外线。由此可推断出，LED被放置在托架内是为了提供紫外线帮助二氧化钛更好地工作。故选C。

4.推理判断题。文章第一段最后一句“But what if those surfaces could clean themselves?”第二段“Two teenagers from Hong Kong asked themselves the same question. Now they’ve developed a door handle that can kill germs on contact.”来自香港的两个青少年问了自己同样的问题。现在他们已经开发出一种能在接触时杀死细菌的门把手。第三段中“In lab tests, their system killed about 99.8 percent of the germs ....” 在实验室测试中，他们的系统杀死了99.8%的细菌；第五段“After doing some research, they learned that a mineral called titanium dioxide(二氧化钛）is known to kill bacteria. It’s already used in many products” 他们发现一种矿物称为二氧化钛杀死细菌。它已经被用在很多产品中；第八段“And here’s the interesting part: The power that makes the UV light shine comes from opening and closing the door.”有趣的是：紫外线照射的能量来自开关门。根据文中的用词“killed about 99.8 percent of the germs ”、“It’s already used in many products”和“And here’s the interesting part:”这些字里行间可推断出作者对这项发明的态度很热情。故选C。