Transcript UNIT 2 CLASSIFICATION

UNIT 7
Vocabulary
• Conventional Power Plants:
– Thermal power plant
– Nuclear power plant
– Hydroelectric power plant
Grammar and functions
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Expressing sequence
Revision of vb tenses (regular & irregular vbs)
Active vs. Passive
Revision of grammar structures
SEQUENCE
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First / Firstly / First of all / The process begins /commences / starts with
In the first step / stage / The first step / stage is .... / To begin with
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Secondly/ After this, / Later, / Afterwards/ Then, / Next, / Subsequently
In the following / next stage, / The next step is ...
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At the end of the process / In the last stage/ The last step / stage is ....
Finally / Eventually.. finishes / concludes with
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So far, / Up to now
Before this / Previously, / Prior to this / Earlier, / In the preceding / previous
/ former stage
At the same time,/ During .... / Simultaneously, / While ... / Meantime /
Meanwhile / As ... / In the meantime / When ...
OTHER EXPRESSIONS
The process takes place / occurs / happens
To carry out / develop a process
by means of ... / (by) using ... / With the help of ...
One method for /way of ... (+ verb –ING) .... is to ....
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TRANSLATION
• GREAT/LARGE AMOUNTS OF ELECTRICITY
CANNOT BE GENERATED UNLESS
• that IS DONE BY MEANS OF/WITH A TURBINE
• INTO
• WHICH IS THE MAGNET and a rotor, WHICH IS
THE COIL
• WHEN/AS THE ROTOR TURNS
• PRODUCING AN ALTERNATING CURRENT
• AT WHICH
• AS MUCH AS HALF A MILLION VOLTS
• IN WHICH THE VOLTAGE IS REDUCED BY
(MEANS OF THE USE OF) USING
TRANSFORMERS
TRANSLATION
• BY/ BY MEANS OF / WITH a turbine
• or STEAM IN POWER PLANTS
• ACCORDING TO/DEPENDING ON THE SOURCE
OF ENERGY USED
• Those produced by THE CHEMICAL ENERGY
OF/FROM FOSSIL FUELS, LIKE/SUCH AS OIL
OR COAL.
• WHICH WORKS LIKE a big kettle.
• AFTER BEING HEATED (UP) TO A CERTAIN
TEMPERATURE
• and MAKE IT (THEM) TURN .
ACTIVE vs PASSIVE
Passive voice:
• The agent (doer) of the action is NOT IMPORTANT or UNKNOWN
• To EMPHASIZE the first part of the sentence
• Typical VOICE in TECNICAL ENGLISH, particularly when describing
processes.
The pyramids were built thousands of years ago.
The samples were analysed in the laboratory
The mixture is fed into the pulveriser.
NOTE:
– Some verbs have NO PASSIVE (intransitive, impersonal) = e.g. RAIN,
OCCUR, BECOME, RISE
– Be careful with Spanish expression “se + vb”:
e.g. se lava las manos = he washes his hands;
los polos se atraen = the poles attract each other
- Placement of SUBJECT: (with vbs like THINK, BELIEVE, CONSIDER,
ESTIMATE, REQUEST …)
- The atom was thought to be the smallest particle;
- Students are requested to register in the university website;
- renewable energy is believed to be the answer to climate change
PASSIVE VOICE
TO BE (changing verb) + Past Part of MAIN VERB.
The system …..
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PRESENT = IS
PRESENT CONT= IS BEING
PAST = WAS
PRESENT PERFECT = HAS BEEN
PAST PERFECT = HAD BEEN
WITH MODAL VB = CAN/MUST BE
WILL / SHOULD = BE
+ DEVELOPED
•AGENT = BY (por) = The system was developed BY the engineers of the plant
• if an object = BY / BY MEANS OF / USING = The system was developed BY
MEANS OF / USING a new technique
HOW POWER PLANTS WORK
http://www.youtube.com/watch?v=GI7AhajfhWE
1. Most power plants produce what? Heat in order to generate steam to drive
turbines that generate electricity
2. Which are the main fuels? Nuclear fission, natural gas and coal
3. Which fuel is used in W C plant? Coal to produce heat
4. Furnace boiler: How does the system capture the heat? Using a system of
circulating water and steam
5. Process: Step 1
1. Which process takes place in the boiler? Combustion
2. Step 2: pulverized COAL is injected with a stream of AIR into the FURNACE through a
BURNER
3. Step 3: Burners IGNITE THE COAL-AIR MIXTURE -> maximum heat possible= AS MUCH
AS 1500ºC
6. The steam turbine generator: converts THE HEAT captured BY THE
STEAM INTO ELECTRICIAL ENERGY
1. Intense HEAT coming FROM THE FURNACE turns WATER RUNNING THROUGH THE
PIPES around the boiler INTO STEAM
2. Steam travels THROUGH MORE PIPES to THE TURBINE causing it TO SPIN and turn the
shaft of A GENERATOR, which CREATES ELECTRICITY
3. Another series of pipes ALLOWS THE STEAM TO COOL condensing back INTO WATER
heading back to THE BOILER where THE PROCESS BEGINS AGAIN in a continuous cycle
VERB TENSES
Nuclear energy is the energy RELEASED through the fission
or fusion of atomic nuclei.
In the process KNOWN AS nuclear fusion two light atoms join
together UNDER conditions of extreme HEAT and
PRESSURE (at LEAST 50,000,000 degrees Celsius) until
they merge, forming a new nucleus WHOSE mass is only
slightly smaller THAN the total masses of the nuclei that
FUSE/ARE FUSED.
The opposite process is nuclear FISSION which MEANS
“splitting apart” or “dividing”.
If either nuclear fusion or fission TAKES place quickly, the
result is a sudden release of ENERGY but so far the only
one THAT can BE SLOWED down and CONTROLLED is
fission.
VERB TENSES
• only a few elements are suitable FOR use IN this way, the most
important ones BEING U-235, U-233 and Pu-239.
• When one of THESE elements is STRUCK by a free neutron,
IT BREAKS/ IS BROKEN down INTO two lighter nuclei,
WHICH fly apart AT high speeds, colliding WITH surrounding
atoms.
• This kinetic energy IS CONVERTED INTO heat.
• AT the same time, two or three more neutrons ARE
RELEASED and one of THEM enters the nucleus of a
neighbouring atom, causing fission TO OCCUR again,….
• The reaction SPREADS very quickly with more and more
energy RELEASED.
• This IS REFERRED to as A “chain” reaction because the
splitting of each nucleus IS LINKED to another.
VERB TENSES
• If this reaction IS UNCONTROLLED, the result is an
atomic explosion like THAT/THE ONE CAUSED by the
atomic bombs of Hiroshima and Nagasaki.
• However, the reaction can BE SLOWED down and that
is WHAT happens in a nuclear reactor or pile.
• Here the highly fissile material IS SURROUNDED BY a
substance that is non-fissile, FOR instance, graphite.
• This material IS CALLED A moderator.
• The neutrons LOSE some of THEIR energy through
COLLIDING with the atoms of the moderator and no
expansion IS PRODUCED .
• by SLOWING down the speed of the free neutrons, IT
makes it …. collide WITH the nucleus of a neighbouring
atom to continue the chain REACTION
VERB TENSES
• The major advantage of nuclear energy is that it DOES
NOT DEPEND ON any local factors.
• A nuclear reactor, UNLIKE conventional power plants,
DOES not have TO BE BUILT near a fossil-fuel source,
nor does it depend ON a large flow of water WHICH may
BE REDUCED during some seasons of the year.
VERBS (regular&irregular)
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TO TAKE
TOOK TAKEN
TO SPLIT
SPLIT SPLIT
TO WIND
WOUND WOUND
TO FEED
FED FED
TO SET
SET SET
TO DRIVE
DROVE DRIVEN
TO ALLOW
ALLOWED
TO FLOW
FLOWED
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TO KNOW
KNEW KNOWN
TO SHOW
SHOWED SHOWN
TO LEAVE
LEFT LEFT
TO STRIKE
STRUCK STRUCK
TO LET
LET LET
TO SEE
SAW SEEN
TO CUT
CUT CUT
TO LEAD
LED LED
VERBS (regular&irregular)
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TO SUPPLY
SUPPLIED
TO DRAW
DREW DRAWN
TO SPREAD
SPREAD SPREAD
TO RAISE
RAISED
TO BUILD
BUILT BUILT
TO SPEND
SPENT SPENT
TO FIND
FOUND FOUND
TO MAKE
MADE MADE
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TO THROW
THREW THROWN
TO WRITE
WROTE WRITTEN
TO RISE
ROSE RISEN
TO HOLD
HELD HELD
TO BREAK
BROKE BROKEN
TO CAST
CAST CAST
TO BRING
BROUGHT BROUGHT
GRAMMAR REVISION: THE NUCLEAR REACTOR
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… place IN which a fission NUCLEAR reaction TAKES place.
It contains …in THE form of rods to produce the appropriate result.
The reactor consists OF a fuel, a moderator and A cooling system.
An instrument …neutron WHICH strikes the nucleus of an atom of
U-235.
The nucleus … which collide WITH other nuclei and split, and so on.
However, if no explosion occurs IT is because …is moderated BY a
non-fissionable material such AS graphite or heavy water.
This absorbs most OF the free neutrons and prevents them FROM
splitting too MANY nuclei too quickly.
The process releases great AMOUNTS of energy in the form of
heat.
This heat ….produced can be USED to generate electric power.
As the fuel … during ITS use inside the reactor, when IT is taken
…, IT is stored in the fuel pools, …, in general more THAN a year,
before sending IT to the processing plant.