air conditioner

A conditioner is a liquid that you put onto your hair after washing it to make it softer, or a liquid that you wash clothes in to make them softer. AC是Air conditioning或交流电(alternating current)的缩写。

One in every three worldwide air conditioners is manufactured by Gree [格力] and rated Global No. 1 air conditioning manufacturer. Gree has nine production bases and its current air conditioning annual capacity is 60,000,000 sets of Residential (RAC) and 5,500,000 sets of Commercial (CAC). Gree has been rated by Forbes [福布斯] as Top 385 Global best company amongst 2000 companies above all other air-con competitors. Gree products are amongst the most technically advanced, efficient and environmentally friendly on the market today.

Air conditioning is also used to cool and dehumidify [去湿] rooms filled with heat-producing electronic devices, such as computer servers, power amplifiers [功率放大器], and to display and store some delicate products, such as artwork.

Air conditioners often use a fan to distribute the conditioned air to an enclosed space such as a building or a car to improve thermal comfort [热舒适度] and indoor air quality. Wall-mounted air conditioning units are popular.

Air-conditioning dates back to prehistory. Ancient Egyptian buildings used a wide variety of passive air-conditioning techniques. The 2nd-century Chinese inventor Ding Huan of the Han Dynasty invented a rotary fan for air conditioning, with seven wheels 3 m (10 ft) in diameter and manually powered by prisoners.

In 1758, Benjamin Franklin and John Hadley, a chemistry professor at Cambridge University, conducted an experiment to explore the principle of evaporation [蒸发] as a means to rapidly cool an object. In 1820, English scientist and inventor Michael Faraday [法拉第]discovered that compressing and liquefying ammonia [氨水] could chill air when the liquefied ammonia was allowed to evaporate.

James Harrison's first mechanical ice-making machine began operation in 1851 on the banks of the Barwon River at Rocky Point in Geelong, Australia. His first commercial ice-making machine followed in 1853, and his patent for an ether vapor compression refrigeration system was granted in 1855.

The creation of the modern electrical air conditioning unit and industry is credited to the American inventor Willis H. Carrier. The first air conditioner, designed and built in Buffalo, New York by Carrier, began working on 17 July 1902. Designed to improve manufacturing process control in a printing plant [印刷厂], Carrier's invention controlled not only temperature but also humidity.

In 1906, Stuart W. Cramer of Charlotte was exploring ways to add moisture to the air in his textile mill. Cramer coined the term "air conditioning", using it in a patent claim he filed that year as analogous to "water conditioning", then a well-known process for making textiles [纺织物] easier to process.

The first air conditioners and refrigerators employed toxic or flammable [有毒或易燃] gases, such as ammonia, methyl chloride, or propane, that could result in fatal accidents when they leaked. Thomas Midgley, Jr. created the first non-flammable, non-toxic chlorofluorocarbon gas, Freon [氟利昂,氟氯代甲烷和氟氯代乙烷的总称] (R-12), in 1928. In 2011 the EPA decided in favor of the ozone- [臭氧] and climate-safe refrigerant for U.S. manufacture. HFCs [含氢氟烃] 对臭氧层无害但contribute to climate change problems... being replaced with HFO [Hydrofluoroolefin,氢氟烃] and hydrocarbon [碳氢化合物] refrigerants...R-600 (isobutane,异丁烷) is already widely used in residential refrigeration. 给充气式打火机充气就能体验到制冷的效果，制冷剂也是某烷。:-) 一般是丁烷、丙烷或液化气(主要成分为丙烷,丙烯,丁烷,丁烯中的一种或两种)。剧毒的是氢氰酸，尝了没死的是瑞典化学家舍勒。牙膏都含氟的。食盐还氯化钠呢。

Most modern air-conditioning systems feature a dehumidification [抽湿] cycle during which the compressor [压缩机] runs while the fan is slowed as much as possible to reduce the evaporator [蒸发器] temperature and therefore condense more water. When the temperature falls below a threshold [阈yu值], both the fan and compressor are shut off to mitigate [减轻] further temperature drops; this prevents moisture on the evaporator from being blown back into the room. When the temperature rises again, the compressor restarts and the fan returns to low speed. 室内evaporator，室外condenser. the fan is slowed as much as possible...把凉气吹走了蒸发器就不够凉了。把它附近弄干了，房间里的空气是流通的，也就干了。直接整个房间零下10度空调做不到(起码电费交不起)，人也受不了。

In 2015, 90% of U.S. households had air conditioning. The U.S consumes more energy for air conditioning than the rest of the world. In China, the proportion of urban [城市] households with air conditioners increased from 8% to 70% in 9 years, from 1995 to 2004. In 2016, it was predicted that by 2031, there would be an additional 700 million air conditioners worldwide. As of 2018, 1.5 billion air conditioning units were installed, with the International Energy Agency expecting 5.6 billion units in use by 2050. 到时人口是多少？

六级/考研单词: liquid, clothe, alternate, manufacture, globe, electron, compute, delicate, seldom, enclose, thermal, outdoor, passive, dynasty, diameter, manual, professor, conduct, evaporate, rapid, compress, chill, patent, carrier, buffalo, humid, textile, mill, refrigerator, toxic, fatal, leak, thereby, condense, threshold, farther, consume, million, billion, install