Nuclear knowledge in life -- X-ray security inspection machine
June 5 is the world environment day designated by the United Nations General Assembly. It reflects the understanding and attitude of people all over the world towards environmental issues and expresses human yearning and pursuit for a better environment. It is one of the main media for the United Nations to promote global environmental awareness, raise government attention to environmental issues and take action.
On this day, most countries in the world will hold a series of publicity activities to raise the awareness of the whole society to participate in environmental protection and jointly build a beautiful earth home. In the next few days, we will share the relevant knowledge of world environment day with you to promote all sectors of society to better participate in biodiversity conservation. Today, Safeagle will take you to know about "nuclear safety".
Yes, this is the X-ray security machine that plays an important role in traffic security.
I believe that when you first saw this magical machine when you were children, you will be curious about this machine that can be seen through without opening your luggage. What can the X-ray security machine see? Will the X-ray security opportunities we often pass have an impact on our health?
What does the X-ray security machine see?
How did you see it?
X-ray, also known as roentgen ray, is a kind of ray invisible to the naked eye. It has the ability to penetrate substances, but its penetration ability is different for different substances, so the amount of X-rays reaching the screen or film is different. By forming black-and-white contrast images on the screen or X-ray film, you can clearly see the internal appearance of the object.
I believe everyone has been X-rayed during the physical examination. However, the X-ray security inspection machine is very different from the X-ray machine used in hospitals. The components inside the human body are highly consistent, which are all meat and bones, but our luggage is diverse. Security inspection not only needs to observe the shape of the objects in the luggage but also is very important for the identification of the material of the objects in the luggage. Ordinary medical X-ray machines use a single set of detectors and can only generate black-and-white pictures. How to identify the dangerous goods in the luggage? This is not difficult for intelligent R & D personnel. Researchers use two groups of detectors in the X-ray security inspection machine to send high-energy and low-energy signals respectively so that they can obtain two groups of data. It seems that if x and y are determined in the rectangular coordinate system, a point can be determined. By analyzing these two groups of signals by computer, we can accurately know the material of the object, and then identify it by different colors, Have a basic reflection on the items in the package.
On the monitor of the X-ray security machine
The picture is like this
The radiation dose of the baggage security detector is about 1% of that of the medical x-ray imager. Since the four sides of the baggage security detector are shielded with a certain thickness of lead curtain, the radiation dose on the outer surface of the security detector can be reduced by about two orders of magnitude, so that the external radiation level is within the background range. Therefore, even people who travel often will not be exposed to too much radiation. In fact, even for security personnel, radiation has no effect on their health.
Safeagle use double-layer lead curtain and thickened lead plate. Each security inspection machine has been tested with radiation detector to ensure no leakage
However, safety belongs to safety, and radiation always exists. For our health, we should avoid unnecessary radiation based on the principle of "avoid if possible". Before taking the subway, I once saw an elder sister in a hurry. Because she thought the delivery was slow, she even reached into the curtain of the security check machine to get the bags that have not completed the security check. This is very inappropriate. When we go through the security check, we should wait for the luggage to be completely sent out from the security check machine before reaching for it. If the conveyor belt is stuck or the baggage is stuck in the security check machine, please ask the staff for help.
Nuclear knowledge in life -- X-ray security inspection machine-Safealge