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Masers and lasers

A great technical advance is under way. It is the advancement to develop the amazing new scientific devices called "masers" and "lasers".

Hundreds of physicists, engineers, and technicians are working in laboratories throughout the United States, Great Brit­ain and other technically advanced countries. Each month brings word of new significant advances. Problems and diffi­culties are many, but the achievements are already great and the promise for the future is enormous.

Masers and lasers provide the first positive method for generating controlled and uniform10 light, and radiations like light which men cannot see with their eyes but can receive with their instruments.

The name "maser" itself provides good clues to follow. It is one of the words known as acronyms — each letter stands for a word in a significant phrase: "Microwave Amplification by Stimulated Emission of Radiation"=m -a-s-e-r.

Laser has the same origin, but replaces the M for "microwave" with an L for "light". (You use other acronyms constantly. Do you know, for example, about the basis for the word radar? It is an acronym for "Radio Detecting and Ranging").

The year 1951 may stand as the birthday of the idea of the maser, as such.

Various scientists were thinking along similar lines, for important technical problems have a way of inspiring similar solutions in different places — science develops freely with interchange6 of information.

While sitting in a park one spring morning, the originator of the maser Dr. Charles H. Townes, was thinking about very small things - microwaves.

Townes was a physics professor at Columbia University in New York City. He tried to find ways to extend to still higher frequencies the range of microwaves that one can use in communication work.

Grammar and lexical exercises

I.State the forms and functions of the Participles; translate the fol­lowing sentences into Ukrainian.

The experiment being made at our laboratory shows the action of catalysts. 2. The temperature used depended upon the substances entering the reaction. 3. The figures following show the dependence of the rate of reaction on temperature. 4. Efforts being made in the development of chemical industry meet with great success. 5. The success achieved in the develop­ment of industry resulted in a considerable growth of the well-being of the people. This does not mean, nowever, that we can be satisfied with the results obtained. 6. Science has opened out possibilities for the conquest of nature hardly dreamed of a few years ago. 7. The experiments referred to in our article demonstrate the action of catalysts in chemical reactions. 8. The substance acted upon by heat changed its composition. 9. The molecules of a substance affected by a catalyst are changed more easily. 10. This reaction, when completed, will give us a new proof of the use of catalysts in living systems.

II. Translate into Ukrainian paying attention to the Participle I, II.

1. He heard the voices coming through the open window. 2. Waiting for him l looked through the magazines lying on the table. 3. They remained at home refusing to go anywhere that day. 4. The channel linking the two seas is being built now. 5. The explanation given was not complete. 6. The new materials recommended for bridge construction were described in the article written by our professor. 7. The results received were of great importance for further work. 8. A balsa tree found in South America is lighter than any other. 9. Having passed all the examinations he left for Kjiv. 10. Having been shown the wrong way I could not find his house. 11. Having waited for him for half an hour they went home. 12. Having obtained the necessary results they stopped their experimental work.