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Страница 44.

Например:
На улице было много людей. «There were many people in the street».
С определенным артиклем people обычно имеет значение «народ»:
Русский народ достиг крупных успехов в науке. «The Russian people has achieved great successes in science».
Народы многих стран строят социализм. «The peoples of many countries are building Socialism».
§ 41. В данном параграфе приводятся отрывки из статей, напечатанных в современных журналах. Эти отрывки мы рекомендуем проанализировать на употребление артиклей, исходя из приведённых в предыдущих параграфах примеров.
The problem of keeping a grinding operation going at full load with feed of variable size and hardness, and still produce a grind with consistent screen analysis has been solved by a closed circuit system under full automatic control. An outstanding example of the controlled closed circuit system has been in use since early 1959 in a large eastern iron ore mine. Automatic controls for the installation were designed in cooperation with the customer's engineers and built by Trans-Wiegh Company, Pennsylvania. The installation includes four closed circuit grinding lines regulated by individual control systems, plus separate Belt-Meter units that measure and record total tonnages of plant output — iron concentrates and pyrites *.
Effect of Interstitial Gases
One proposal for the mechanism of initiation of detonation involves grain burning started by means of the compressional heating of interstitial gases in the pressing. Compression may be considered
1 Canadian Mining Journal, May 1961, p. 77.
6 А. Л. Пумпянский 81
to take place by a single shock along the Hugoniot, by a series of compressions along a curve approximating anadiabat, or even by means of a clearcut shock reflection. Regardless of these details, the temperature can be altered at least 500° С by choosing gases with widely different hydrodynamic and thermodynamic properties. In order to achieve extremes in this sort of behavior, we have evacuated wedges and replaced the air either with argon, to produce high gas temperatures, or with methane, to produce low gas temperatures. The results of these tests are shown in Fig. 6; the fact that these depths of initiation agree withinexperimental error with the values for air is taken as strong indication that the temperature of the inter-stital gas has nothing to do with the mechanism of initiation. Temperature differences of several hundred degrees would have a profound effect on the rate of grain burning or on the rate of chemical reaction if such temperature changes could be brought to bear on these processes. It is possible that a change in efficiency of //zeheat transfer process compensates for the change in temperature when different gases are used.
An experiment was also performed in which the pressure of the interstitial air was reduced to the range between 50—100. The temperature of the compressed residual air in this case was not much different from that achieved at normal density, but the total amount of energy available for transfer from gas to PETN was lowered by a factor of about 10*. This low-pressure shot is also shown in Fig. 6, and again demonstrates that the interstitial gases did not affect the initiation process г.
The Elastomer Section
For this discussion, static compression stress or static shear stress can be considered the stress which is exerted on the elastomer by normal rated torque delivery. Dynamic stress is that which is produced by cyclical forces or excitations originating from the power source or driven unit, or by excursions caused when misalignment is accommodated by the coupling.
Static stress, if held to practical limits, is not the major criterion for determining service life of the elastomer. Fatigue life of elastomers is a function of the severity and frequency of dynamic strain.

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