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Файл:Materials Processing Technology Part 2. Coursebook
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STUDY SKILL The prepositions of time (2)
Endpoint /Limit: by and (with)in
The prepositions by and within, in most cases shortened to in, represent a
limit or the point at which something ends. By is similar to since in that it
indicates the ‘name of the time.’
In is similar to for in that it indicates the period between the moment of speaking
and the ‘name of the time.’
The following diagram shows the parallels between the four prepositions:
Time indication
Beginning
End
Point of Time
Period of Time
since
for
by
(with)in
by
(with)in
The machine must be
finished
by Saturday.
by 2020.
by 3:00 p.m.
by the time he retires.
in four days.
in 10 years.
in a few hours.
in his working lifetime.
_____3 Fill the blanks with by or (with)in.
1. The Golden Gate bridge was completed _____ 1937.
2. The explosion takes place _____ a fraction of a second.
3. The wooly mammoth was extinct ____ 10,000 B.C.
4. ______ the time reactor was brought under control, most of the nuclear fuel
was uncovered.
5. All the fruit must be harvested _____ the first frost.
6. The final plans for the building are due ____ 8 a.m. Monday morning.
7. The medicine should be taken once _____ the morning and once _____ the
evening.
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STUDY SKILL The prepositions of time (3)
Time Period: during, throughout, and over
The preposition during indicates ‘at some point in a certain time
period’:
The booster rocket is ejected during the first phase.
Duration in units of time is shown with the preposition for:
Incorrect: John studied there during six years.
Correct: John studied there for six years.
The preposition throughout indicates ‘for the whole time.’
It rains here throughout the year.
The patient was conscious throughout the operation.
Like during, the object of throughout must be a complete unit of time,
not duration in units of time:
Mary was an excellent chemist throughout her 25 years career.
Mary was excellent chemist for 25 years.
The time preposition over indicates a repeated or continuous action
leading to a particular result:
The action of wind and water over time can change the shape of rocks
and land contours.
______ 4 Fill the blanks with during, throughout, or over.
1. Wolves stay with one mate ______ their lifetime.
2. Bridal Falls in Yosemite National Park was formed _____ the Ice Age.
3. The volcano continued to erupt intermittently ______ the next several weeks.
4. No one will be allowed to enter the studio ______ the recording session.
5. Some tumors develop ______ periods of several years.
6. Ice can develop on the wings of planes _____ cold weather.
7. Radioactive exposure badges must be worn _____ the test procedure.
8. Our planet was formed _____ millions of years from the same primordial
material as the sun.
9. Plants require sunlight _____ their growing periods.
10. Products are checked ______ the production process, not just when the
product is finished.
11. A single lava is insufficient: samples must be taken _____ a period of several
days.
12. Stars radiate enormous energy _______ the process of formation.
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STUDY SKILL Using a dictionary: electric or electrical?
electric
adj.
– needing electricity to work, produced by electricity, or
used for carrying electricity: electric light/ kettle /cooker/ guitar;
electric power/ current / charge
electrical
adj.
– relating to electricity: electrical equipment /
appliances
_____1 Choose the correct word in bold ‘electric’ or ‘electrical’.
1. Electrical /electric conductivity is a measure of how well a material
accommodates the movement of an electrical / electric charge.
2. Texturing is achieved by passing high-intensity electrical/electric
sparks of short duration across the gap between the roll (workpiece) and a tool
electrode, through which a liquid dielectric is flushed.
3. Machine shop equipment include horizontal mills, vertical mills, lathes
and turning centers, grinders, electrical /electric discharge machines, welding
machines, and inspection machines.
4. Robotic light sensors work by creating or changing an electrical
/electric signal when light falls on them.
5. Solenoids are electri/electrical motors for producing linear or in-andout motion.
6. The hardware is the mechanical, magnetic, electronic, and electric
/electrical devices composing a computer system.
7. The transducer incorporates a piezoelectric element, which converts
electrical/electric signals into mechanical vibrations and mechanical vibrations
into electrical / electric signals. Many factors, including material, mechanical
and electric/ electrical construction, and the external mechanical and electric /
electrical load conditions, influence the behavior of a transducer.
8. The active element is the heart of the transducer as it converts the
electrical/ electric energy to acoustic energy, and vice versa.
9. Conversion of electric /electrical pulses to mechanical vibrations, and
the conversion of returned mechanical vibrations back into electric/ electric
energy is the basis for ultrasonic testing.
10. When an electric/electrical field is applied across the material, the
polarized molecules will align themselves with the electrical /electric field,
resulting in induced dipoles within the molecular or crystal structure of the
material.
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11. In eddy current testing, electrical / electric currents (eddy currents) are
generated in a conductive material by a changing magnetic field.
12. The absorption of thermal energy in the detectors raises the temperature
of the device, which in turn changes some temperature-dependant parameter,
such as electric / electrical conductivity.
13. Quantum detectors do not rely on the conversion of incoming radiation
to heat, but convert incoming photons directly into an electrical/electric signal.
14. Electrical /electric and mechanical systems are the backbone of many
manufacturing operations.
15. In electrical /electric arc welding two workpieces are welded by an
electrical /electric arc.
16. In electric/electrical resistance welding heat to form the weld is
generated by the electric/ electrical resistance of material combined with the
time and the force used to hold the materials together during welding.
SPEAKING Preparing a presentation
____1 Give a 5-10 minute presentation to the members of your group. The
possible topics are as follows:
a) Ceramic engineering
To find information on the topic, go to the site New World Encyclopedia at
http://www.newworldencyclopedia.org/entry/Ceramic_engineering
b) Machining Ceramics with Rotary Ultrasonic Machining
To find the information, use the site Ci Ceramic Industry at
https://www.ceramicindustry.com/articles/83906-machining-ceramics-withrotary-ultrasonic-machining
c) Ultrasonic Machining
To find the information, use the website Ci Ceramic Industry at
https://www.ceramicindustry.com/articles/88824-ultrasonic-machining
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Unit 5
Semiconductor lasers Solid-state lasers Fiber lasers
Gas lasers
Maximum Permissible Exposure (MPE) Nominal Hazard Zone (NHZ)
Optical Density (OD) Accessible Emission Limit (AEL)
Laser Output Pulse energy Irradiance Radiant exposure
Lasers
“Laser” is an acronym for “Light Amplification by Stimulated Emission
of Radiation”, coined in 1957 by the laser pioneer Gordon Gould. Although this
original meaning denotes a principle of operation (exploiting stimulated
emission from excited atoms or ions), the term is now mostly used
for devices generating light based on the laser principle. More specifically, one
usually means laser oscillators, but sometimes also includes devices with
laser amplifiers.
Laser technology is at the core of the wider area of photonics, essentially
because laser light has a number of very special properties:
It is usually emitted as a laser beam which can propagate over long
lengths without much divergence and can be focused to very small spots.
It can have a very narrow optical bandwidth, whereas e.g. most lamps
emit light with a very broad optical spectrum.
It may be emitted continuously, or alternatively in the form of short or
ultrashort pulses, with durations from microseconds down to a few
femtoseconds.
These properties, which make laser light very interesting for a range
of applications, are to a large extent the consequences of the very high degree
of coherence of laser radiation.
Common types of lasers are
Laser terminology
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The following figure shows basic components of a laser system
1. advantage
A. a computer that should be able to perform most
common computing tasks
2. challenge
B. the identification of a system's physical components
and their interrelationships
3. device
C. is dangerous, especially to people's health or safety
4. digital
integrated
circuit
D. to keep something in good condition by
regularly checking it and repairing it when necessary
5. equipment
E. a highly miniaturized electronic circuit, operating on
individual voltage levels, fitted into a small package
6. flexible
F. a program or system which is modelled on the human
brain and is designed to imitate the brain's method of
functioning, particularly the process of learning
READING Laser and electron beam making
___1 Read the texts from Unit 12 of the Textbook.
___2 Survey the texts from Section 12.1, 12.2 and underline the
information which answers the questions.
1. What does LASER stand for?
2. What do all lasers have in common?
3. What are lasers used for?
4. What are the main methods of laser drilling?
5. What is the structure of electron beam gun?
6. What are the main parameters of EBM?
7. Describe the most significant differences between the two systems with
respect to the electron beam gun and power supply.
VOCABULARY DEVELOPMENT
___1 Match the following words and phrases with their definitions and
characteristics.
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7. general-
purpose
computer
G. something new
and difficult which requires great effort and determina
tion
8. hardware
architecture
H. the storing or processing of data on a computer using
the internet
9. hazardous
I. an object that has been invented for a
particular purpose, for example for recording or
measuring something
10. maintain
J. an electromagnetic actuator that converts digital
pulses of input into analog rotary motion, the degree
of rotation being proportional to the number of pulses
received.
11. neural
network
K. sound waves transmitted above the human-detectable
frequency range, usually above 20,000 Hz
12. on-line
processing
L. a way in which one thing is better than another
13. stepping
motor
M. the tools, machines etc. that you need to do a
particular job or activity
14. ultrasonic
waves
N. object or material which can be bent easily without
breaking
___ 2 Fill the gaps with the words from Ex. 1.
1. Imitating humans, robots also sense magnetic fields and _____________.
2. In engineering, _____________ refers to the identification of a system’s
physical components and their interrelationships.
3. ________________ are modeled after the human brain.
4. The operation is ____________ or uncomfortable for the human worker
(for example: spray painting, spot welding, arc welding, and certain
machine loading and unloading tasks).
5. Such devices as automatic pilots, automatic telephone _____________ and
automated control systems are used to perform various operations much
faster and better than could be done by people.
6. They are very easy in operation, their programming is simple and you can
always test it. Moreover, they are cheaper to ___________ and are
generally more accurate in comparison with standard machine tools.
7. Throughout history, inventors have produced a variety of seemingly
magical mechanical _____________ capable of quite life-like actions.
8. In __________ automation the number of products is limited so that the
changeover of the equipment can be done very quickly and automatically.
9. In general, all machine tools that are equipped with NC systems have a lot
of ____________. One of the most important ___________ is the absence
of necessity to design, build and store the numerous fixtures.
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____3 Practice the words online: https://quizlet.com/398214773/lasers-
STUDY SKILL Adjective Compounds
An adjective compound consists of two or more words connected
by a hyphen.
The geologist collected a rare-earth sample. ( = the geologist collected
a representative of one of the elements known as rare earths, i.e.
elements known as the lanthanide series).
NOTE: Without a hyphen the meaning changes:
The geologist collected a rare earth sample. (= the geologist collected
a sample of earth which was rare, i.e. not commonly found).
The tendency in modern scientific writing is to use the hyphen for
adjective compounds only. However, older texts, often use hyphens
between the nouns in a noun compound as well.
Adjective compounds usually do not have a corresponding nonhyphenated form. They express the following grammatical
relationships:
1. measurement
a three-meter cable (the cable is three meters long)
a 110-volt outlet
2. two substances
an oil-water suspension (the suspension contains oil and water)
a copper-constantan thermocouple
plastic-metal combinations
3. attributes
a U-shaped tube (the tube has a U shape)
a furnace-produced iron
a high-intensity laser
4. verb-object relationship
sulfur-containing additives (the additives contain sulfur)
a self-regulating system
5. a verb-adverb relationship (NOTE: Some writers do not consider the
hyphen to
be necessary in this construction.)
a widely-used substance (the substance is used widely)
a fully-developed program
6. combinations
a 50-cycle, high-pass filter
a thin-film, metal-base transistor
flash-cards/?new
58
____ 1 Define the grammatical relationships between the components of the
heat resistant alloys
computer-integrated system
high-voltage power supply
closed-looped, five-axis
system
motor-driven axis
heat-affected zone
barrel-shaped holes
general-purpose machine
emergency-stop button
near-surface flaws
single-element transducer
wax-based substance
rust-proof steels
stress-intensity factor
following adjective compounds (measurement, two substances, attributes, a
verb-object relationship, a verb-adverb relationship, or combinations?).
_____2 Make the following phrases into adjective compounds.
Example: a pump is driven by gear
Answer: a gear-driven pump
1. the highway is 5,000 kilometers long
2. a reaction is induced by drugs
3. the complex contains copper and ammonia
4. an artery has thick walls
5. this method is used widely
6. a figure has three sides
7. the sandstone bears oil
8. the truck weighs five tons
9. chemicals are considered in a synthetic manner
10. the city air is free of smoke and low in particulates
____ 3 Add a hyphen to the following sentences where necessary.
1. Einstein described the space time continuum.
2. Sutter Labs is an industrial chemistry laboratory.
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3. A 1 kilowatt power amplifier has been installed.
4. A trimaran is a three hulled boat.
5. Chlorofluorocarbons disrupt the ozone layer chemistry.
6. Only use a glass microscope slide.
7. The pulley has a V shaped notch.
8. The device utilizes a constant level speech processing system.
9. This circuit requires thin film, metal base transistors.
GRAMMAR DEVELOPMENT
Active vs passive
Sample sentences
A highly collimated, monochromatic, and coherent light beam is generated
and focused to a small spot. High power densities are then obtained. A large
variety of lasers are available in the market including solid-state, ion, and
molecular types in either continuous wave or pulsed mode of operation. Lasers
are widely used in many industrial applications including plating, heat treatment,
cladding, alloying, welding, and machining.
Form
Every active sentence has at least two parts:
A subject [1] + an active verb form [2]
We normally produce a preliminary analysis.
[1] [2]
Every passive sentence has at least two parts:
A subject [1] + a passive verb form [2]
A preliminary analysis is normally produced.
[ 1 ] [ 2 ]
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