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Radioisotopes in industry

The radiation emitted by radioisotopes is being utilized in a variety of useful ways.

One way is measuring or testing industrial products, another is tracing the most complicated chemical reactions, still another is producing that for the generation of electric power.

Radioisotopes often do a job better than conventional methods do. Some­times they do jobs conventional devices can't do at all.

Since their radiation can easily be followed radioisotopes are being widely used as tracers.

We know of the petroleum industry being an early user of radioisotopes to transport different liquids and oil. A radioisotope placed between different liquids or grades of petroleum signals where the flow of one product ends and the other begins. Radiation from the isotope also indicates the rate of flow along the length of the pipeline. By using this tracer method the engineers today are able to examine parts of various engine designs after testing, to learn facts about their wear and the efficiency of lubricants. Radioisotopes are widely employed in thickness gauges for all sorts of coated materials which are manufactured in continuous rolling sheets. In such a gauge a radiation beam from an isotope is passed through or re­flected from the material being manufactured. Even the tiniest variations in the thickness will result in varying the strength of this beam and in a reading on the gauge. Gauge readings are fed electronically into a device that automati cally adjusts the manufacturing process so as to ensure the correct thickness of the material.

Radiation gauges have the advantage of eliminating mechanical contact with the material being measured. They also give an accurate and uninterrupted reading no matter how fast the sheet flows. We have mentioned of radioisotopes being used to trace chemical reactions. Moreover radiation itself is used to change to molecular structure of substances, the materials with new properties being obtained. Many plastics products now in use have undergone this treatment. Plastics treated by radiation can be stron­ger, more heat-resistant and easier to dye.

Everyone knows of chemical batteries losing its power after a time, especially under constant use. Radioisotopes give off heat as well as radiation and this heat can readily be converted into a steady and long-lasting supply of electric current by means of a device known as a thermocouple. The current thus generated can be used to continuously recharge conventional batteries.

Thus, it is radioisotopes that are capable of supplying electric power for years. It may be expected that other radioisotopic devices will be utilized one day for providing reliable and long-lasting sources of electricity for space­ships during manned flights.

Grammar and lexical exercises

I. Translate (he following sentences into Ukrainian paying attention to the Modal Verbs with the Perfect Infinitive.

1 The earliest life forms ought to have appeared over three billion years ago. 2. Chance mutations may not always have been successful. 3. The tropical zone should have suffered most from the process of erosion. 4. The condensation theory proposes that the Sun could have formed from a large cloud of dust and gas. 5. The decay of radioactive elements ought to have heated the Earth until its internal temperature rose to about 7000 °С. 6. A generation ago it may have been restricted discussion of environmental modi­fications to fauna, flora and soil. 7. In nature genetic experiments must have been constantly carried out.

II\. Translate the following sentences into Ukrainian paying atten­tion to the Modal Verbs with Perfect Infinitive.

1. Something must have happened to our TV set; it is out of repair. 2. Absolute accuracy cannot be expected with this kind of instrument; you should take the mean of several observations. 3. You should have tested the device more carefully considering its importance. 4. The pilot should have made use of radar in locating the position of the plane. 5. The operator ought to have known the radio fundamentals better. 6. The scope must have been out of order; that is why the data obtained were not displayed continuously. 7. The operator could have detected the target in time; somebody may have switched off the receiver. 8. The new device must have been broken by acci­dent. 9- The instrument may have been improved, because it became more accurate.