Read the text again and choose the correct ending for the sentences below
1. Smart materials change when
b) something affects them.
c) the light is switched on.
d) they are put into a human body.
2. Plastic threads are used for
3. Medical implants made from shape memory alloys are good because
a) they save lives.
b) they change colour.
c) they are easy to put in.
d) they react to changes in temperature.
4. Climbing ropes with liquid crystals change colour to
a) warn you.
b) amuse you.
c) make you heavy.
d) make you different from other climbers.
6.23 Find in the text words that mean the following:
1. materials made from mixing two metals
2. to change because something else happens
3. everything around a person or thing
4. the first or earliest
5. something medical put inside the body, e.g. a heart valve
6. to become bigger
7. that can bend or be bent easily
8. a situation in which something is holding weight and so might break
9. the ability to form pictures or ideas in your mind
10. small and not very important or serious
Think of a smart material that could be used in the field of your specialization. Discuss your ideas with a partner.
6.25 Fill in the table with the words from the list. Which of them are derived from other words? Which of them have their own derivatives? What are they?
alloy, brass, brittle, bronze, cast iron, ceramic, corrode, diamond, ductile, durable, fibre, flexible, harden, knot, melt, nylon, opaque, platen, powder, resin, resist, rigid, rod, rust, set, soften, steel, stitch, strong, thermoset, thread, tough, transparent, tube, undergo, weak, wire, withstand
Fill in the gaps choosing one of the words in brackets
Plastics are usually produced by synthesis from such natural materials as water, air, salt, coal and natural gas. The technology is simple and cheap. While (1) _____ (solid, cheap, uniform) in finished state, plastics are liquid at some stage of manufacture, and it is easy to form plastics into various shapes. Plastics are different in (2) _____ (hardness, properties, needs), characteristics and (3) _____ (pressure, application, thermosets). Plastics are (4) _____ (reliable, available, thermoplastics), (5) _____ (expensive, cheap, structural), durable. Plastics resist (6) _____ (weight, strength, corrosion). Plastics are machined like (7) _____ (metals, ceramics, carbon).
Their (8) _____ (lightness, high weight, colour), strength, hardness, chemical resistance,(9) _____ (colour, durability, application) make it possible to use plastics in electric and electronic equipment, transportation, agriculture, etc.
The application of plastics is (10) _____ (achieving, satisfying, calling for) the requirements of all industries. There is no industry now where plastics are not used.
6.27 Answer the following questions:
1. What materials are usually used to build bridges?
2. What properties are important for such materials?
6.28 Listen to the text ‘Experimental Bridge’ and complete your answers if there is any new information in the text. Why is the bridge experimental?
6.29 Listen again. What do the following numbers refer to?
32 ft; 80 ft; 10 ft; 4 ft; 2 months; 12,000 lb; 9,000 lb
6.30 Answer the following questions:
1. What are the advantages and disadvantages of this experimental bridge?
2. Do you think the material used for constructing it could be used for this purpose?
6.31 Think of a material used in everyday life and answer the following questions:
1. What are the properties of this material?
2. Why is it used this way?
3. Could it be used somewhere else?
Design a project where a widespread material is used unusually, like paper for constructing bridges. Describe the advantages and disadvantages of using this material for the purpose.
7.1 What is nanotechnology? Try to guess from the meaning of the parts of the word.
centimeans ‘one hundredth’, so 1 centimeter equals one hundredth of a meter. Match these prefixes and their meanings to learn what the prefixnanomeans.