2211-东北官话
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C3 TEST 1
PASSAGE 1:
The rocket from east to west
A
The concept
of the rocket, or rather the mechanism behind the
idea of propelling an object
into the
air, has been around for well over two thousand
years. However, it wasn't until the
discovery of the reaction principle,
which was the key to space travel and so
represents one of
the great milestones
in the history of scientific thought, that rocket
techn0108y was able to
develop.
Not
only
did
it
solve
a
problem
that
had
intrigued
man
for
ages,
but,
more
importantly, it literally opened the
door to exploration of the universe.
B
An intellectual
breakthrough, brilliant
though it may
be, does not
automatically ensure that
the
transition
is
made
from
theory
to
practice.
Despite
the
fact
that rockets
had
been
used
sporadically
for
several
hundred
years,
they
remained
a relatively
minor
artefact
of
civilization until the twentieth
century. Prodigious efforts accelerated during two
world wars,
were required before the
technology of primitive rocketry could be
translated into the reality
of
sophisticated astronauts.
It is strange
that the rocket was generally ignored by writers
of
fiction
to
transport
their heroes
to
mysterious
realms
beyond
the
Earth,
even
though
it
had
been commonly used in fireworks
displays in China since the thirteenth century.
The reason
is that nobody associated
the reaction principle with the idea of travelling
through space to a
neighboring world.
C
A simple
analogy can help us to understand how a rocket
operates. It is much like a machine
gun
mounted on the rear of a boat. In reaction to the
backward discharge of bullets, the gun,
and hence the boat, move forwards. A
rocket motor's 'bullets' are minute, high-speed
particles
produced by burning
propellants in a suitable chamber. The reaction to
the ejection of these
small
particles
causes
the
rocket
to
move
forwards.
There
is
evidence
that
the
reaction
principle was applied practically well
before the rocket was invented. In his Noctes
Atticae or
Greek Nights, Aulus Gellius
describes 'the pigeon of Archytas', an invention
dating back to
about 360BC. Cylindrical
in shape, made of wood, and hanging from string,
It was moved to
and
fro
by
steam
blowing
out
from
small
exhaust
ports
at
either
end.
The
reaction to
the
discharging steam provided the bird
with motive power.
D
The
Invention
of
rockets
Is
linked
inextricably
with
the
invention
of
'black
powder'. Most
historians
of
techn0108Y
credit
the
ChInese
with
its
discovery.
They
base
their
bellef
on
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studies of
Chinese writings or on the notebooks of,'early
Europeans who settled in or made
long
visits to China to study its history rand
civilisation. It is probable that, some tIme in
the
tenth
century,
black
powder
was
first
compounded from
its
basic
ingredients
of
saltpetre,
charcoal and
sulphur. But this does not mean that it was
immediately used to propel rockets.
By
the
thirteenth
century,
powder- propelled
fire
arrows
had
become
rather
common.
The
Chinese relied on this type of
technological development to produce incendiary
projectiles of
many
sorts,
explosive
grenades
and
possibly
cannons
to
repel
their
enemies.
One
such
we was
the 'basket of fire' or, as directly translated
from Chinese, the 'arrows like I leopards'.
The 0.7 metre-long arrows, each with a
long tube of gunpowder at a near the point of each
arrow, could be fired from a long,
octagonal-shaped bat the same time and had a range
of 400
paces. Another weapon was the
'arrc a flying 'sabre', which could be fired from
crossbows.
The rocket, placed in a
position to other rocket-propelled arrows, was
designed to increase
the
ran!
small
iron
weight
was
attached
to
the
l.5m
bamboo
shaft,
just
below
the
feai
to
increase the arrow's stability by
moving the centre of gravity to a position to the
rocket. At a
similar time, the Arabs
had developed the 'egg which move burns'. This
'egg' was apparently
full of gunpowder
and stabilized by a l.5m. I was fired using two
rockets attached to either
side of this
tail.
E
It was not until the eighteenth century
that Europe became seriously interested in the
possibilities of using the rocket
itself as a weapon of war and other weapons. Prior
to this,
rockets were used only in
pyrotechnic disincentive for the more aggressive
use of rockets
came not from within the
European continent but from far-away India, whose
leaders had
built up a corps of
rocketeers and used rockets successfully against
the British in the late
eighteenth
century. The Indian rockets used against the
British were described by a British
Captain serving in India as 'an iron
envelope about 200 millimetres long and 40
millimetres
in diameter with sharp
points at the top and a 3m-long bamboo guiding
stick'. In the early
nineteenth century
the British began to experiment with incendiar:
rockets. The British rocket
differed
from the Indian version in that it was completely
encased in a stout, iron cylinder,
terminating in a conical head,
measuring one metre in diameter and having a stick
almost five
metres long and constructed
way that it could be firmly attached to the body
of the rocket.
The Americans developed
a rocket, complete with its own launcher, to use
against the
Mexicans in the mid-
nineteenth century. A long cylindrical tube was
propped up by two
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sticks and
fastened to the top of the launcher, thereby
allowing the rockets to be inserted and
lit from the other end. However, the
results were sometimes not that impressive as the
behaviour of the rockets in flight was
less than predictable.
F
Since then, there have been huge
developments in rocket technology, often
devastating
results in the forum of
war. Nevertheless, the modern days programs owe
their success to the
humble beginnings
of those in previous cent who developed the
foundations of the reaction
principle.
Who knows what will be like in the future?
C3 TEST1 PASSAGE 2:
The risks of cigarette smoke
Discovered in the early
1800s and named nicotianine, the oily essence now
called nicotine is
the main active
ingredient of tobacco. Nicotine, however, is only
a small component of
cigarette smoke,
which contains more than 4,700 chemical compounds,
including 43 cancer-
causing substances.
In recent times, scientific research has been
providing evidence that years
of
cigarette smoking vastly increases the risk of
developin3 fatal medical conditions,
In addition to being responsible for more than 85
per cent of lung cancers, smoking is
associated with cancers of, amongst
others, the mouth, stomach and kidneys, and is
thought
to cause about 14 per cent of
leukemia and cervical cancers. In 1990, smoking
caused more
than 84,000 deaths, mainly
resulting from such problems as pneumonia,
bronchitis and
influenza. Smoking, it
is believed, is responsible for 30 per cent of all
deaths from cancer and
clearly
represents the most important preventable cause of
cancer in countries like the United
States today.
Passive smoking, the breathing in of
the side-stream smoke from the burning 0f tobacco
between puffs or of the smoke exhaled
by a smoker, also causes a serious health risk. A
report
published in 1992 by the US
Environmental Protection Agency (EPA) emphasized
the health
dangers, especially from
side-stream smoke. This type of smoke contains
more, smaller
particles and is
therefore more likely to be deposited deep in the
lungs. On the basis of this
report, the
EPA has classified environmental tobacco smoke in
the highest risk category for
causing
cancer.
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As an illustration of the health risks,
in the case of a married couple where one partner
is a
smoker and one a non-smoker, the
latter is believed to have a 30 per cent higher
risk of death
from heart disease
because of passive smoking. The risk of lunf3
cancer also increases over
the years of
exposure and the figure jumps to 80 per cent if
the spouse has been smoking four
packs
a day for 90 years. It has been calculated that 17
per cent of cases of lung cancer can be
attributed to high levels of exposure
to second-hand tobacco smoke during childhood and
adolescence.
A
more recent study by researchers at the University
of California at San Francisco (UCSF)
has shown that second-hand cigarette
smoke does more harm to non-smokers than to
smokers.
Leaving aside the
philosophical question of whether anyone should
have to breathe someone
else's
cigarette smoke, the report suggests that the
smoke experienced by many people in their
daily lives is enough to produce
substantial adverse effects on a person's heart
and lungs.
The report,
published in the Journal of the American Medical
Association (AMA), was based
on the
researchers' own earlier research but also
includes a review of studies over the past
few years. The American Medical
Association represents about half of all US
doctors and is a
strong opponent of
smoking. The study suggests that people who smoke
cigarettes are
continua fly damaging
their cardiovascular system, which adapts in order
to compensate for
the effects of
smoking. It further states that people who do not
smoke do not have the benefit
of their
system adapting to the smoke inhalation.
Consequently, the effects of passive
smoking are far greater on non-smokers
than on smokers.
This
report emphasizes that cancer is not caused by a
single element in cigarette smoke;
harmful effects to health are caused by
many components. Carbon monoxide, for example,
competes with oxygen in red blood cells
and interferes with the blood's ability to deliver
life-
giving oxygen to the heart.
Nicotine and other toxins in cigarette smoke
activate small blood
cells called
platelets, which increases the likelihood of blood
clots, thereby affecting blood
circulation throughout the body.
The researchers criticize
the practice of some scientific consultants who
work with the
tobacco industry for
assuming that cigarette smoke has the same impact
on smokers as it does
on non-smokers.
They argue that those scientists are
underestimating the damage done by
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