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1) Characteristic of carbon dioxide and application fields of its sensors Our planet is surrounded by a layer of atmosphere, of which oxygen accounts for about 21%, 78% is nitrogen, and 1% is other gases. Among these 1% gases, a small part is carbon dioxide, about 350-450 ppm (one millionth, or 0.03...

In tropospheric atmosphere, atmospheric pollutants mostly diffuse vertically or horizontally from the ground, while solar radiation, as an important driving force of atmospheric chemical reactions, transmits from top to bottom. Therefore, the study of atmospheric environmental chemistry should not o...

In tropospheric atmosphere, atmospheric pollutants mostly diffuse vertically or horizontally from the ground, while solar radiation, as an important driving force of atmospheric chemical reactions, transmits from top to bottom. Therefore, the study of atmospheric environmental chemistry should not o...

Macro-control of grain is the main means to maintain national food security, and grain depot is the basis of macro-control of grain. Therefore, intelligent control and precise management of grain depots are the key to achieve safe and efficient grain storage. The most important thing in grain storag...

First of all, you need to understand the negative effects of oxygen! Oxygen is an indispensable gas for human survival. Without oxygen, humans can asphyxiate in a few minutes. It is unknown that the damage to human beings should not be neglected when the oxygen content is too high. In addition, oxyg...

Chlorine is a toxic gas with a yellowish-green color and a strong irritating odor. It can cause sneezing, coughing, tearing, asphyxia and other symptoms. It mainly invades the human body through the respiratory tract and dissolves in the water contained in the mucosa, producing hypochlorite and hydr...