By the end of this unit, students will be able to
• explain the properties of materials, using collocations;
• describe the materials’ features impersonally by means of passive voice;
• comprehend a speech about an application of nanotechnology;
• discuss the importance of advanced materials technology.
Preliminary
Read the text and examine the expressions in bold typeface.
COMPOSITES AND ADVANCED MATERIALS
Different materials can be combined and grouped by the types of materials combined or the way the materials are arranged together to create a more complex material.
Composites
A composite is composed of two (or more) individual materials, such as metals, ceramics, and polymers. The design goal of a composite is to achieve a combination of properties that is not displayed by any single material and also to incorporate the best characteristics of each of the component materials. Fiberglass, for example, is one of the most common and familiar composites, which combines small glass fibers and a polymeric material (normally epoxy or polyester). It has the strong and stiff quality of the glass fibers and theflexible quality of the polymer.
Advanced materials
Advanced materials are novel materials that are utilized in high- technology (or high-tech) applications. These materials are usually synthesized, improved or designed to achieve high performance in very specific tasks. Advanced materials include semiconductors, nanomaterials, biomaterials and smart materials, which may be termed “materials of the future”.
Semiconductor materials have electrical properties that are intermediate between the electrical conductors and insulators. That is, they have the ability to switch from electrical insulators to conductors by applying external voltage. For these properties, semiconductors are at the center of electronic industry with various applications such as computers, mobile phones, tablets, cameras, and smart TV.
Nanomaterials are materials whose sizes typically range from 1 to 100 nanometers. The sizes and/or geometries can have strong impacts on the properties of thematerials. They can present interesting or even strange properties compared with bulk materials. For example, gold nanoparticles can be very chemically active, unlike bulk gold.
Biomaterials are new materials that can be implanted into our bodies. They are able to perform their designed functions and show the ability to survive in living bodies.
Smart materials are materials designed to imitate biological behaviors. The adjective “smart” implies that these materials are able to sense changes in their environments and then respond to these changes in predetermined manners.
(Synthesized from different sources) Language Focus
Vocabulary
COLLOCATIONS
In the text, there are varioussentences about the characteristics of materials. Each contains a particular fixed group of words. This fixed
combination is referred to as “collocation”. In this unit, we will look at the collocations describing a state.
Collocation Meaning
be composed of … be made or formed from several parts, things or people
be at the center of … be more involved in (something) have the property of …
(variants:‘display/show/present the property of …’)
have/show a quality or
characteristic that something has
have/show the ability to (do
something) be able to (do something) or
possess a skill or talent to (do something)
have/make an impact on … show the powerful effect on … range from … to …(variant:
range between … and …) vary between two particular amounts or sizes
switch from … to … change or make something change from one thing to another
Activity 1. Complete the following sentences by filling in each numbered gap with an appropriate collocation in the list above.
1. A kind of material that ……… high strength and light weight ……… current research in material technology.
2. Plywood ……… thin veneers of wood plies that are sandwiched together with binders, pressed, and heated.
3. Advanced materials ……… all levels of economy and society.
4. Matter ……… solid, liquid, gas, and plasma.
Activity 2. Think about 3 collocations you know. Write them down on a piece of paper and exchange it with a classmate.
Grammar
PASSIVE VOICE
Look at the italicized parts in the following sentences extracted from the text:
[3.1] Different materials can be combined and grouped by the types of materials combined or the way the materials are arranged together to create a more complex material.
[3.2] These materials are usually synthesized, improved or designed to achieve high performance in very specific tasks.
The structure of be + past participle is the passive voice structure, which is a special form in English, as well as in some other European languages. It is used to change the focus of an action. Whereas the focus of active sentences is on the subject doing an action (as in [3.3]), that of passive sentences is on the object that receives an action (as in [3.4]).
[3.3] This company employs 2,000 people.
[3.4] Two thousand people are employed by this company.
As the passive voice gives a sense of objectivity, it occurs in most scientific writing (Ananda, 2012), and thus in documents about materials technology. It is necessary to be well aware of this structure:
Activity 3. The following sentences are in the active voice with the subject “people” being unclear or unnecessary. Rewrite them, emphasizing the action rather than the agent of the action.
1. People use epoxy coatings to prevent corrosive agents, such as water and salts, from coming into contact with rebar.
2. In this book, people will fully examine the biocompatibility of different materials.
3. People can activate multifunctional materials by electrical stimuli so as to produce their geometry change or property change.
4. People introduce raw materials of biopolymers and they review
their active behaviors in terms of electronic and ionic working behaviors.
5. People form composite materials from two or more distinct phases of materials.
6. People have well recognized the development of composite material technology in recreational boats.
Pronunciation
THE RHYTHMIC PATTERNS IN COLLOCATIONS
In spoken language, there is a significant difference between the way individual words are pronounced and the way they are pronounced in a sequence. As English is a stress-timed language, we often try to make the intervals between stressed syllables equal when we speak in order to give the phrase rhythm by swallowing some non-essential words (i.e., we pronounce them weakly).
Conjunctions, pronouns, prepositions, auxiliaries and articles are often lost in a phrase. These are some examples:
at the center of
Instead of pronouncing in the strong form: /ổt ðə ˈsentə ʌv/, we tend to pronounce this phrase as /ət ðə ˈsentə əv/.
switch from … to …
For this collocation, the preposition from and to are often pronounced in the weak forms /frəm/ and /tə/.
Activity 4. Now create the rhythmic patterns in collocations by practicing the weak forms.
come to an agreement make a mistake perform an experiment pay the respects to
conduct a survey run out of time
incorporate … into … draw the attention to
Can you tell what kind of words that need the strong form of pronunciation in a collocation?
Skills Focus Listening
Activity 5. You are going to listen to a talk about a new high- tech product. As you listen, fill in each numbered gap with a word or a phrase from the list below. There are extra words/phrases that you do not need.
measure robotic reactions genius
contact discovery classed ever
revert convert holder mankind
incredible folder rotates just
SCIENTISTS MAKE MOLECULE-SIZED ELECTRIC MOTOR
Scientists have made the smallest electric motor (1)………
created. It is a feat of scientific (2)……… that most of us could never even try to understand. Dr. Charles Sykes and his team from America’s Tufts University created the motor from a single molecule (3)……… a billionth of a meter wide. Dr. Sykes is in (4)……… with the Guinness Book of World Records to have his motor recognized as the smallest ever.
The current world-record (5)……… is a 200-nanometre-long nano-tube made from carbon. Dr. Sykes’ creation is an (6)………
200 times smaller. Naturally, the researchers hope their creation has uses for (7)………. It will be used to power the tiniest machines ever built, and be used by doctors in nano-surgery and (8)……….
It is the first time an electric motor has been made from a single molecule. Scientists can make molecules (9)………energy from light and chemical (10)………into movement, but Dr Sykes’
invention is the first to be(11)……… as a motor – something that can continually generate power. There is some mind-boggling science behind Sykes’ device. A combination of chemicals and metals produces the minuscule motor that (12)……… 50 times a second. Dr Sykes was excited about the future of his (13)………, saying: “The next thing to do is to get the thing to do work that we can (14)……… - to [link] it to other molecules, lining them up next to one another so they’re like miniature cog-wheels.”
(Adapted from Breaking News English, September 7, 2011) Speaking
NANOTECHNOLOGY DISCUSSION
Activity 6. Work in pairs. Choose one of the following suggested questions to discuss. When you have finished, present your ideas in class.
1. Do you think the molecule motor is a feat of scientific genius?
2. How do you think scientists can work with and make things that are a billionth of a meter wide?
3. What uses do you think the motor will have for mankind?
4. When do you think nanotechnology will be a widely used part of our life?
5. How might nanotechnology help medicine?
6. Why do you think people are interested in nanotechnology?
7. What would the inventors of the first motors over a hundred years ago think of a nanotechnology motor?
(Adapted from Breaking News English, September 7, 2011) Reading
Activity 7. Read the following passage and do the tasks that follow.
METALS, NONMETALS, AND METALLOIDS
All matter is made up of the atoms of different elements. There are more than 100 known elements found in nature. Each element has certain physical properties.
A physical property is a characteristic of a substance that can be observed without changing the substance into another substance. Color, hardness, and luster are physical properties. Luster is the way a substance reflects light. Whether an element is a solid, liquid, or gas is also a physical property under certain conditions.
Physical properties of metals
Iron (Fe), copper (Cu), gold (Au), and silver (Ag) are examples of metals. They are often shiny, malleable, ductile, and can conduct electricity.
A malleable material is one that can be rolled into flat sheets. A ductile material is one that can be pulled out into a long wire. Copper can be made into thin sheets and wire because it is malleable and ductile.
Conductivity is the ability of an object to transfer heat or electricity to another object. Most metals are good conductors. In addition, a few metals are magnetic. For example, iron (Fe), cobalt (Co), and Nickel (Ni) are attracted to magnets. They can also be made into magnets.
Most metals are solid at room temperature except Mercury (Hg) that is a liquid at room temperature.
Physical properties of nonmetals
A nonmetal is an element that lacks most of the properties of a metal.
In general, the physical properties of nonmetals are the opposite of those of metals. Solid nonmetals are dull, (not shiny), brittle (not malleable or ductile). Ten of the 16 nonmetals found in nature are gases at room temperature. Some are solid or liquid at room temperature; some are noble gases which do not ordinarily form compounds.
Physical properties of metalloids
The metalloids have some characteristics of both metals and nonmetals. All are solids at room temperature. They are brittle and hard. They can conduct electricity under certain conditions. The most common metalloid is silicon (Si). Metalloids can vary in how well they conduct electricity. Their conductivity depends on various factors, such as temperature or light. For this reason, metalloids such as silicon (Si) and germanium (Ge) are used to make semiconductors.
I. Decide if each of the statements is true or false.
___ 1. Some metals can be rolled into flat sheets.
___ 2. Rusting is a physical property.
___ 3. All metals are solid.
___ 4. Noble gases do not form metalloids.
___ 5. Metalloids share the characteristics of both metals and nonmetals.
II. Fill in the diagram with the physical properties of metals, nonmetals and metalloids, using the terms in the list.
solid liquid
gas hard
brittle ductile
dull shiny
malleable
good conductivity poor conductivity conductivity varies Writing
PARALLELISM IN WRITING
Parallelism is an important element in English writing, especially when you are listing, and comparing and contrasting items or ideas.
Parallelism means that each itemin a list or comparison follows the same grammatical pattern. If you are writing alist and the first item in your list is a noun, write all the following items as nouns also. If it is an adverb clause, make all the others adverb clauses.
Consider the following pairs of sentences:
[3.5] a. The teacher wanted to know which country we came from and our future goals.
b. The teacher wanted to know which country we came from and what our future goals were. (The items are both noun clauses.)
[3.6] a. The students who attend class, they do their homework, and practice speaking in English.
b. The students who attend class, do their homework, and practice speaking in English. (The items are all verbs + complements.)
Activity 8. Rewrite the following sentences in parallel form.
Remember that you do not have to repeat all the words in the second item.
1. The disadvantages of using a credit card are overspending and you pay high-interest rates.
………
………
2. Credit cards are accepted by department stores, airlines, and they can beused in some gas stations.
………
………
3. You do not need to risk carrying cash or to risk to miss a sale.
………
………
4. With credit cards, you can either pay your bill with one check, or you can stretch out your payments.
………
………
5. You can charge both at restaurants and when you stay at hotels.
………
………
6. Many people carry not only credit cards but they also carry cash.
………
………
7. Many people want neither to pay off their balance monthly nor do they like paying interest.
………
………
8. Not making any payment or to send in only the minimum payment everymonth is poor money management.
………
………
(Source: Oshima & Hogue, 2006, pp. 179-182)