Convert the following phrases into compound nouns.

 

1. release of chemicals, gases or oil

2. releases of poisonous gases

3. gases from car exhaust pipes

4. core of a nuclear power plant

5. melt-down of core

6. emission of gases

7. burning of fossil fuels

8. depletion of the ozone layer

9. degradation of natural habitat

10. reduction of biodiversity

Read the text

Cosmic Ray Hazard

   In the laboratory, cosmic rays first presented themselves as a minor annoyance. They were discovered when physicists no­ticed that electrically charged bodies do not stay that way; their charge slowly leaks away through the air. Something had to be ionizing the air, allowing it to conduct electricity. Many researchers blamed the ambient radioactivity of the soil and rocks underfoot. Austrian physicist Victor Hess settled the issue in 1912, when he went aloft in a balloon and showed that the higher he rose, the faster the charge leaked off his electroscope. So the cause of the ionized air was something mysterious coming in from space − thus the name "cosmic rays."

By 1950 physicists had determined that the term is actually a misnomer. Cosmic rays are not rays but ions − mostly protons, with a few heavier nuclei mixed in − striking the top of the atmosphere at nearly the speed of light. Most come from beyond the solar system, but what catapults them to such a speed remains a question to this day. Experimenters, having once regarded cosmic rays as irksome, embraced them as an observational tool. Variations in cosmic-ray intensity were one of the ways scientists deduced the existence of the solar wind in the late 1950s.

  Contrary to popular belief, it is not Earth's magnetic field that shields people on the ground from the full brunt of these rays but rather the bulk of our atmosphere. Above every square centimeter of surface is a kilogram of air. It takes a vertical column of about 70 grams − about 1/4 the distance through the atmosphere, achieved at an altitude of 20 to 25 kilometers (60,000 to 80,000 feet − before the average incoming proton hits the nucleus of an atom in the air. The rest of the atmosphere serves to absorb the shrapnel of this initial collision. The impact knocks a proton or neutron or two out of the nucleus and un­leashes a shower of high-energy gamma rays and pi meson, or pion, particles. Each gamma ray propagates deeper into the atmosphere and ends up producing an electron and its antimat­ter counterpart, a positron. These two particles annihilate each other, yielding less energetic gamma rays, and so the cycle con­tinues until the gammas become too weak to create particles. Meanwhile the pions quickly decay into mu mesons, or muons, which penetrate to the ground. As they pass through our bodies, they produce ions and break chemical bonds but not enough to do us significant harm. The annual cosmic ra­diation dose of about 0.03 rem (depending on altitude) is equivalent to a couple of chest x-rays. Outside the atmosphere, the cosmic-ray bombardment is intense. Approximately one proton or heavier nucleus would pass through your finger­nail every second, for a to­tal of perhaps 5,000 ions zipping through the body every second, each one leaving a trail of broken chemical bonds and triggering the same cascade that occurs in the atmosphere. The relatively few heavier nuclei among the cosmic rays do as much or more damage than the protons be­cause their ability to break bonds is proportional to the square of their electric charge. An iron nucleus, for example, does 676 times more damage than a proton does. A week or a month of this radiation should not have serious consequences, but a couple of years on a journey to Mars is a different story. One estimate from NASA is that about one third of the DNA in an astronaut's body would be cut by cosmic rays every year.

The only quantitative information available on the biological consequences of energetic radiation comes from the unfortunate individuals who have been exposed to short but intense bursts of gamma rays and fast particles during nucle­ar explosions and laboratory accidents. They have suffered cell damage and enhanced cancer rates. A Mars traveller would get similar doses, albeit spread out over time. No one knows whether the two situations are really equivalent but the comparison is worrisome. Natural biological repair mech­anisms may or may not be able to keep up with the damage.

  The implications have been recently studied by scientists, they estimated that Mars astro­nauts would receive a dose of more than 80 rems a year. By comparison, the legal dose limit for nuclear power plant work­ers in the U.S. is five rems a year. One in 10 male astronauts would eventually die from cancer, and one in six women (be­cause of their greater vulnerability to breast cancer). What is more, the heavy nuclei could cause cataracts and brain dam­age.

 

4. Find equivalents to the following phrases using the text :

- досадная неприятность;

- подниматься на воздушном шаре,

- чем выше он поднимался, тем быстрее разряжался его электроскоп;

- изменения в интенсивности космических лучей;

- порождать ливень гамма-лучей высокой энергии и пи-мезоны;

- ежегодная доза космического излучения;

- способность ядер разрывать химические связи пропорциональна квадрату их электрического заряда;

- страдать от разрушения клеток и более частых случаев рака;

- один из 10 мужчин-астронавтов в конце концов умрет от рака.

 

5. Form phrases by matching the words from 1-13 with the words a-m:

1) minor 2) electrically 3) quantitative 4) available 5) underfoot 6)solar 7) cell 8) cancer 9) incoming    10) antimat­ter  11) energetic 12) serious 13) chemical

 

a ) proton b) damage c) rocks  d) information e) bonds  f) rates

g) consequences  h) counterpart i) charged j) system k) annoyance

l) information m) radiation

 

TALKING POINT

6. Discuss in pairs:

· the reason for electrical charge leaking away from charged body;

· if the name “cosmic rays” is actually a misnomer;

· explanation of the solar wind;

· the shield preventing people from the full brunt of cosmic rays;

·  the consequences of cosmic rays passing through the body of a man;

WORD FORMATION

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