Reading
Task 7
Read Passage 1 about"History of Refrigeration"and then work in pairs to speak out the common expressions given in brackets.
1.The first attempt to produce refrigeration mechanically depended on______（冷却效应）of the evaporation of water.
2.In the______（闭式循环），air confined to the machine at a pressure higher than the atmospheric pressure was utilized repeatedly during the operation.
3.Franz Windhausen invented a closed-cycle machine and______（申请了专利）in America in 1870.
4.In Germany，Carl Linde paved the way for great improvements in______（制冷机械）by demonstrating how its thermodynamic efficiency could be calculated and increased.
5.In addition to its______（热力学优势），the pressures it required were easy to produce，and machines which used it could be small in size.
6.______（二氧化碳压缩机）became important，because of the gas's harmlessness，in installations where safety was the primary concern，although they were not used extensively until the 1890s.
7.By 1890，mechanical refrigeration had proved to be both practical and economical for the______（食品冷藏行业）.
8.Steady______（技术进步）in the field of mechanical refrigeration marked the years after 1890.
Passage 1
Task 8
Read the passage again and supply the missing words or expressions to complete the following statements.
1.At least as early as the second century,______was used in ancient India to make ice.
2.A number of inventions for clarifying the______have been created by many engineers and scientists.
3.Compressed-air or cold-air machines which use______played a significant role in refrigeration history.
4.American professor Alexander C.Twining invented and patented one of the earliest of the______machines in 1853.
5.In the late 1860s,P.H.Van der Weyde of Philadelphia obtained a patent for a compression unit which______made up of petroleum products.
6.Inventors also tried ammonia as the______in compression refrigerating machines,and the use of ammonia became popular for many years.
7.Most of the______were provided by Europeans for the development of mechanical refrigeration.
8.Revolutionary changes were not the rule,but in several countries,many improvements were made in the______and in their basic components,compressors,condensers,and evaporators.
Task 9
Work in groups and discuss the following questions.
1.When and where did people begin to use the cooling effect of water evaporation?
2.How did William Cullen accomplish his ice making in 1755?
3.What are the two types of refrigerating machines that use cold air as a refrigerant?
4.What are the compressed-air machines?
5.What were used as refrigerants in refrigeration history?
Task 10
Read the following sentences taken from Passage 1 and work in groups to translate them into Chinese.
1.The first attempt to produce refrigeration mechanically depended on the cooling effects of the evaporation of water.
_____________________________________________
2.In 1834,Jacob Perkins,an American residing in England,constructed and patented a vapor-compression machine with a compressor,a condenser,an evaporator,and a cock between the condenser and the evaporator.
_____________________________________________
3.In the open cycle,air was drawn into the machine at atmospheric pressure and,when cooled,was discharged directly into the space to be refrigerated.
_____________________________________________
4.Europeans provided most of the theoretical background for the development of mechanical refrigeration,but Americans participated vigorously in the widespread inventive activity between 1850 and 1880.
_____________________________________________
5.Revolutionary changes were not the rule,but many improvements were made,in several countries,in the design and construction of refrigerating units,as well as in their basic components,compressors,condensers,and evaporators.
_____________________________________________
Task 11
Work in pairs to complete the following statements with the information from Passage 2.
1.The term HVAC & R is a shorted form of and______.
2.An air conditioning is made up of components and equipment arranged in sequence to______,to______,and to control the indoor environmental parameters of a specific space within required limits.
3.According to their applications,air conditioning systems can be classified as______and______.
4.Comfort air conditioning systems have various sectors including the commercial sector,the______,the______,the______and the transportation sector.
5.Hospitals generally use______to remove bacteria and particulates of submicrometer size from areas such as operating rooms,nurseries,and intensive care units.
6.Process air conditioning systems offer______for several areas such as manufacturing,product storage,research and development processes.
7.Temperature control can be performed by refrigeration systems only,but the simultaneous control of______in the space can only be performed by process air conditioning systems.
Passage 2
Task 12
Read the passage again and work in pairs to translate the following expressions into Chinese or English.
