2008年职称爱沙尼亚语试题预测及教材变动复习重点

二〇〇八年教材上新增了大致17篇作品,词汇选项,阅读判断, 概括大意完毕句子,
阅读了解, 补全短文, 完型填空种种题型上都有新增作品。
理工类和卫生类新增的小说更显示专业性。新增小说的言语难度和难点考点设置意况在肯定程度上反映了08年课题的出题趋势。

The APU is a small jet engine that is used to start the larger jet
engines. In airliners it’s usually at the very rear of the aircraft,
below the tail. Large engines are heavy and require a lot of torque to
spin up, more than a starter battery can generate. So, the battery spins
up a much smaller APU jet engine. High-speed bleed air from the APU is
used to spin up the main engine.

(难度B/A级/二〇〇八年理工类教材新增作品)

Once the engines are started, the APU is no longer required, but it does
provide a couple of secondary functions:

The Tiniest Electric Motor in the World

  • It provides cabin air and electric power before the engines are
    started (saving battery power).
  • It provides an emergency source of electric power in the event of
    engine failure.
  • It can start the aircraft engines mid-flight in an emergency.
  1. Scientists recently made public the tiniest electric motor ever
    built. You could stuff hundreds of them into the period at the end of
    this sentence. One day a similar engine might power a tiny mechanical
    doctor that would travel through your body to remove your disease.

  2. The motor works by shuffling(来回运动) atoms(原子) between two
    molten metal droplets(小滴) in a carbon nanotube(微米管). One
    droplet is even smaller than the other. When a small electric current is
    applied to the droplets, atoms slowly get out of the larger droplet and
    join the smaller one. The small droplet grows – but never gets as big as
    the other droplet – and eventually bumps into the large droplet. As they
    touch, the large droplet rapidly sops up (吸入)the atoms it had
    previously lost. This quick shift in energy produces a power
    stroke(引力行程).

  3. The technique exploits the fact that surface tension — the tendency
    of atoms or molecules to resist separating — becomes more important at
    small scales. Surface tension is the same thing that allows some insects
    to walk on water.

  4. Although the amount of energy produced is small — 20
    microwatts(百相当之一瓦) — it is quite impressive(给人纪念深切的)
    in relation to(与…比较) the tiny scale of the motor. The whole setup
    is less than 200 nanometers on a side, or hundreds of times smaller than
    the width of a human hair. If it could be scaled up to the size of an
    automobile engine, it would be 100 million times more powerful than a
    丰田(Toyota) Camry’s 225 horsepower V6 engine.

  5. In 1988, Professor 理查德 Muller and colleagues made the first
    operating(工作的, 运行的) micromotor(微型发动机), which was 100
    microns(飞米) across, or about the thickness of a human hair. In 2003,
    Zettl’s group created the first nanoscale motor. In 2006, they built a
    nanoconveyor(飞米传送带), which moves tiny particles along like cars
    in a factory.

  6. Nanotechnology(飞米技术) engineers try to mimic nature, building
    things atom-by-atom. Among other things, nanomotors could be used in
    optical circuits to redirect light, a process called optical switching.
    Futurists envision(预想) a day when nanomachines(皮米机器), powered
    by nanomotors(微米引擎), travel inside your body to find disease and
    repair damaged cells.

If the APU fails before engine start, the engines cannot be started
without an external “start cart” to provide a source of bleed air. If
the APU fails mid-flight, there will be no immediate effect. Even
without the APU, there are two additional ways to restart an aircraft
engine in flight:

练习:

  • a cross-bleed start, where bleed air from a working engine is used
    to start a dead engine, or
  • a windmill start, where the aircraft dives and attains enough speed
    that ram air spins the turbine fast enough to allow a relight.
  1. Paragraph 2

  2. Paragraph 4

  3. Paragraph 5

  4. Paragraph 6

The APU is normally left off in flight, but may be turned on for certain
long-haul overwater flights as an extra precaution.

A An introduction of a Toyota’s 225 horsepower V6 engine.


B A description of the nanomotor in terms of power and size.

延伸阅读:
An auxiliary power unit (APU) is a device on a vehicle that provides
energy for functions other than propulsion. They are commonly found on
large aircraft and naval ships as well as some large land vehicles.
Aircraft APUs generally produce 115 V alternating current (AC) at 400 Hz
(rather than 50/60 Hz in mains supply), to run the electrical systems of
the aircraft; others can produce 28 V direct current (DC). APUs can
provide power through single- or three-phase systems.
APU Function

C [u]Surface tension[/u](表面张力).

图片 1

D Previous inventions of nanoscale(飞米级的) products.

APIC APS3200 APU for Airbus A320 family.
The primary purpose of an aircraft APU is to provide power to start the
main engines. Turbine engines must be accelerated to a high rotational
speed to provide sufficient air compression for self-sustaining
operation. Smaller jet engines are usually started by an electric motor,
while larger engines are usually started by an air turbine motor. Before
the engines are to be turned, the APU is started, generally by a battery
or hydraulic accumulator. Once the APU is running, it provides power
(electric, pneumatic, or hydraulic, depending on the design) to start
the aircraft’s main engines.

E The working principle of the nanomotor.

To start, a jet engine requires pneumatic rotation of the turbine,
AC-electrical fuel pumps, and an AC-electrical “flash” that ignites the
fuel. As the turbine (behind the combustion chamber) is already
rotating, the front inlet fans are also rotating. After the ignition,
both fans and turbine speed up their rotation. As combustion stabilizes,
the engine thereafter only needs the fuel to run at idle. The started
engine can now replace the APU when starting up further engines. During
flight the APU and its generator are not needed.

F Possible fields of application in the future.

APUs are also used to run accessories while the engines are shut down.
This allows the cabin to be comfortable while the passengers are
boarding before the aircraft’s engines are started. Electrical power is
used to run systems for preflight checks. Some APUs are also connected
to a hydraulic pump, allowing crews to operate hydraulic equipment (such
as flight controls or flaps) prior to engine start. This function can
also be used, on some aircraft, as a backup in flight in case of engine
or hydraulic failure.

点名的八个段子都未曾明了的段子宗旨句(二〇〇七年理工类A/B级概括大意题中七个指定段落都尚未强烈段落焦点句),考生方可通过通读指定段落的疏忽来概括出段落主旨,
或借助一些有效的答题技巧肯定段落主题。以确认段落第4段的段子宗旨为例分析答题技巧:

Aircraft with APUs can also accept electrical and pneumatic power from
ground equipment when an APU has failed or is not to be used. Some
airports reduce the use of APUs due to noise and pollution, and ground
power is used when possible.

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