輪機(jī)英語(yǔ)船舶輔助機(jī)械章節(jié)練習(xí)(2017.12.24)

來(lái)源：考試資料網(wǎng)

1 Which of the listed statements is correct concerning refrigeration systems?（）

2 The process of boiling seawater in order to separate it into freshwater vapor and brine is usually defined as （）.

3 On small, low pressure, air compressors, the cylinders are usually lubricated by the （）.

4 In a refrigeration plant the （） need defrosting.

5 Which of the following statements concerning energy is correct?（）

6 Foaming in the steam drum may be caused by （） in a boiler.

7 A refrigerant boils and vaporizes in the （） in a compression refrigeration system.

8 R-12 is generally considered to be a safe, nontoxic, nonflammable, and non-explosive refrigerantIt can, however, become highly toxic when （）.

9 In the condenser, the hot, high pressure refrigerant gas is cooled by the sea water and becomes（）.

10 The degree to which the viscosity of an oil will change with a change in temperature is indicated by the （）.