1902, an American named "Nathan Stubblefield" installed the first wireless phone in his country house in Murray, Kentucky.
[Nathan Stubblefield]
Nathan Stubblefield.
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Yes, this wireless mobile phone is the earliest exploration and research on' mobile phone' technology.
1938, Bell Laboratories made the world's first mobile phone for the US military.
1in April, 973, marty cooper, a famous engineer and technician of Motorola Company in the United States, invented the world's first civil mobile phone. marty cooper is also known as the father of modern mobile phones.
The invention of air conditioning
Willis Haviland Carrier, an American inventor known as the father of refrigeration, designed and installed the first air conditioning system in 1902. The air conditioning system was designed for a printer in new york, USA. He found that the change of temperature would cause the deformation of paper, which would lead to the imbalance of color ink. Carrier registered the patent 1906.
July 1902 Carrier, a young man who just graduated from Cornell University for one year, invented air conditioning while working in Fudge Company in Buffalo, but the original purpose of air conditioning was not to bring people a comfortable living environment, but to serve some dead things.
It is said that one of Buffalo's customers, William Printing Factory in Xiakete, new york, has a printing machine that causes the paper to expand and contract due to the change of air temperature and humidity, and the ink is misplaced, so that clear color printed matter cannot be printed. So I turned to Buffalo Company. Carrier thinks that since air can be kept warm by coils filled with steam, why not use air to cool down by coils filled with cold water? The moisture in the air will condense on the coil, so that the air in the factory will be cool and dry.
[Central air conditioning host]
Central air conditioning host
1902, 17 July, the air-conditioning era began with the first use of air-conditioning in this printing house. Soon, other industries, such as textile, chemical, pharmaceutical, food and even arms industry, also greatly improved the product quality because of the introduction of air conditioning. 1907, the first buyer to export air conditioners was a Japanese silk factory.
19 15, Carrier established its company, and it is still one of the largest air conditioning companies in the world. But in the 20 years after the invention of air conditioning, it has always been a machine, not a person. Until 1924, in a shopping mall in Detroit, many people often fainted because of the sultry weather. Three central air conditioners were first installed, which was a great success. The cool environment has greatly increased people's desire for consumption. Since then, air conditioning has become a powerful tool for merchants to attract customers, and the era of air conditioning serving people has officially arrived.