We can find many medical devices in our life, and the thermometer could be one of the commonly used one. First, what is called a medical device? It is a product which is used for medical purposes in patients, in diagnosis or surgery. These devices are usually designed with rigorous safety standards. These devices include a wide range of products, such as tongue depressors, thermometer, blood pressure gauge, etc.
What is a thermometer http://www.ecvv.com/company/qdbercon/products.html? Thermometer is a device used to measure temperature or temperature gradient. When did it appear? Who invented it?
The first thermometer was invented by the Italian scientist Galileo in 1593. His first sample of thermometer is a only one end glass tube, and on the other side of the tube, a glass bulb is equipped like a large walnut. Heating should be given to the glass bulb when using it, then put the glass tube into the water. As the temperature changes, the water in the glass tube will move up and down. Therefore, according to the number of water movements, the temperature change and the temperature high or low level can be determined. Thermometer has the characteristic of thermal expansion and cold contraction so that the thermometer can be highly affected by the external atmospheric pressure and other environmental factors. So the first invented thermometer has a large measurement error.
Later, Galileo's students and other scientists did a lot of repeatedly improvements on this base, such as turn the glass upside down, put the liquid in the tube, and close the tube. The more prominent achievement is the thermometer manufactured by a French, named Boulliau, in 1659. He reduced the size of the glass bulb and changed the temperature measuring material into mercury. Such kind of thermometer already have a prototype of the device used today. Afterwards, a Dutch man named Fahrenheit used alcohol in 1709 as the measuring material, then used mercury again in 1714, which led to the creation of a more accurate thermometer. He observed the boiling water temperature, the ice water mixture temperature, salt water and ice mixture temperature, and after repeated experiments, he finally set salt water, which is of a certain concentration, freezing temperature at 0℉, the solidification of pure water temperature at 32℉, and set the temperature of boiling water under the standard atmospheric pressure as 212℉. He used ℉ to represent Fahrenheit, which is the birth of Fahrenheit thermometer.
30 years after the birth of Fahrenheit thermometer, a Swedish, Anders Celsius improved the Fahrenheit thermometer scale in 1742. He determined the boiling point of water at 0 degrees, and the freezing point at 100 degrees. Later, his colleagues Shilemoer reversed the two temperature points, which become the percentage degree of our currently used temperature scale, which is represented as ℃.
Nowadays, Britain and United States usually use Fahrenheit, while in the world scientific community and during industrial and agricultural production, as well as China, France and many other countries all use the Celsius temperature.
Many thermometers and other medical devices can be found here http://www.ecvv.com/product_directory/medical-equipment.html.
1.Resource: http://www.ecvv.com is an innovative and comprehensive business portal in China, dedicated to introduce China qualified products, suppliers and manufacturers to global buyers, and also help global buyers to find much more China qualified products, suppliers and manufacturers.
<a href="http://www.ecvv.com">www.ecvv.com</a> is an innovative and comprehensive business portal in China, dedicated to introduce China qualified products, suppliers and manufacturers to global buyers, and also help global buyers to find much more China qualified products, suppliers and manufacturers.
没有评论:
发表评论