As the first pass to ensure the safety of the subway, the security check aims to check whether the luggage and items carried by passengers are safe, and to carry out targeted detection of suspicious items. But as a public travel mode, the subway has two biggest features: l relatively closed environ

All objects in nature, whether they are Arctic glaciers, flames, human bodies, or even the extremely cold deep space of the universe, will have infrared radiation as long as their temperature is above absolute zero - 273°C. This is due to the thermal movement of molecules inside the object. Its radi

With the development of social economy, there are more and more methods and equipment for safety inspection, and liquid inspection is one of them. I believe most people should have undergone liquid inspection. When you take some liquid into the car or participate in activities, the corresponding sec