The hot and cold -swollen metal -的

Many objects have the characteristics of thermal expansion and contraction. For example, the thermometer we often use is the principle of using the thermal expansion and contraction of mercury. However, there is a kind of metal very different. It will shrink and swell within a certain temperature. Today, I will know this magical metal together.

金 is a silver -gray metal, which is very crispy and easy to melt. It was mistaken for lead or tin. The main mineral is the 锑 锑. This mineral is found in early AD.

my country's ore ore is distributed in Hunan, Guangdong, Guangxi, Yunnan, Guizhou, Sichuan and other provinces. Among them, the tin mines in tin mines in Xinhua County, Hunan Province have the largest reserves. Interestingly, because 被 was once mistaken for tin, the local residents of Xinhua were called "tin mines" after discovering the 矿 mine, and this name has been used to this day.

What is the purpose of that magic?

Alas, most of them are used to melt with lead and make alloys. For example, because of the special nature of the cricket -heat shrinking cold and swelling, people will add some crickets to the diligent alloy. When the melted dotted alloys are poured into the copper mold to cool and solidify, the alloy is slightly inflated, making each small stroke protruding clearly.

Not only that, adding 1%to 20%of 锑 can enhance the hardness and mechanical strength of the lead, so the derivative alloy is harder and wear -resistant, making up for some of the shortcomings of pure lead.

In addition, there are many uses of compounds in the puppet. For example, in semiconductor processes, 锑 can be used to manufacture infrared detectors, diode and Hall sensors; compounds such as oxidation and sulfurized crickets can also be used to make flame retardant, coating, pottery enamel, glass, and so on.

In medical medicine, 用 once used to make many drugs, such as some special effects drugs such as lung disease, hemorrhage, and black fever. They are all organic compounds. The "tadpole" researched by my country's pharmaceutical workers has made great contributions to the completely eliminating blood and insect disease.

Although there are many usefulness, as a heavy metal, the toxicity is very fierce. Poisoning may cause symptoms such as dermatitis, rhinitis, headache, and vomiting. Therefore, we need to pay attention to and pay attention to the use of 锑.

This article was scientifically controlled by Mu Dan, a first -level teacher of the Middle School Affiliated Experimental School Affiliated Experimental School of Haidian District, Beijing.

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