Check points: "small bumps" can be ground with a grinding wheel. The quality of "small pits" is poor. Some sellers use graphite to fill the "eyes", which is difficult to detect. Only a small brush can be used to expose them.
Check the bottom of the pot: the smaller the bottom of the pot, the faster the fire, saving fuel and saving time.
Check the thickness: the thickness of the pot is thin, and the thin one is good. When the identification is made, the bottom of the pot can be turned to the sky. Use your fingers to press against the center of the concave surface, and hit with a hard object. The louder the sound of the pot, the better the finger vibration. Know the "metallography": Iron pan with rust spots indicates that the storage time is longer, and the longer the iron pan is stored, the better.
Chemical barrels are mostly made of plastic. They are also called plastic chemical barrels and plastic chemical barrels. They are made of scientific formula and blow molded. They are various in color and beautiful in appearance. They are resistant to acid and alkali, corrosion and leakage. Fading, non-deformation and other aspects to achieve packaging indicators, is currently the ideal choice for long-distance transportation of chemical product packaging materials.
The plastic chemical barrel has the advantages of one-piece polyethylene (PE) without joints, impact resistance, anti-aging, light weight, no leakage, acid and alkali resistance, long service life, and compliance with sanitary standards. The performance is much better than traditional FRP. Containers, plastic welded containers, steel-lined rubber and other containers.
Specifically, a compound having a cyano group (CN) in which a carbon atom and a nitrogen atom are bonded through a hydrazone bond. This hydrazone bond gives the cyano group a relatively high stability, so that it exists as a whole in the usual chemical reaction. Because this group has similar chemical properties to halogen, it is often referred to as pseudohalogen. Generally, the inorganic compound is classified into a cyanogen, and the organic compound is classified into a nitrile. The commonly known cyanide is inorganic cyanide, commonly known as Shannai (from the English transliteration "Cyanide"), which refers to the inorganic salt containing cyanide ion (CN-), which can be considered as the salt of hydrocyanic acid (HCN). Common potassium cyanide and sodium cyanide. They are highly toxic and therefore well known to the world. Another organic cyanide is formed by combining a cyano group with another carbon atom through a single bond. Depending on the mode of bonding, organic cyanides can be classified as nitrile (C-CN) and isonitrile (C-NC). Correspondingly, cyano can be called nitrile (-CN) or isonitrile (-NC). . The most common cyanides are hydrocyanic acid, sodium cyanide and potassium cyanide.