Based on the principle of atmospheric pressure. In the process of sucking the medicine, when pulling the piston outward, only a small part of the gas inside the syringe becomes larger in volume and the air pressure decreases, while the outside atmospheric pressure remains unchanged, and the atmospheric pressure pushes the medicine into the syringe.
The syringe is a common medical device. As early as the 15th century, the Italians Catinel put forward the principle of syringe. It is mainly used to extract or inject gases or liquids with a needle.
Syringes can also be used for medical devices, containers, such as some chromatography in the scientific instruments injected through the rubber diaphragm.
Expanded InformationSyringes can also be used for medical devices, containers, and scientific instruments such as those used in some chromatography to inject through a rubber septum. Injecting gas into a blood vessel will result in an air embolism. Air is removed from the syringe to avoid embolization by inverting the syringe, tapping it gently, and squeezing out a small amount of fluid before injecting it into the bloodstream.
In settings where precision is the primary concern rather than germs, such as in quantitative chemical analysis, glass syringes are still used because of their small error margins and smooth pushrod movement.
Baidu Encyclopedia - Syringe
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