Head-Loop Mask Machine,Tie-On Mask Machine,Medical Mask Machine,Non-Medical Mask Machine Broadfair Automation Equipment Co., Ltd. , https://www.broadfairmachine.com
Sterling silver is a beautiful white metal whose Latin name comes from Sanskrit, meaning light.
Among all metals, silver has the best conductivity, thermal conductivity and reflectivity to visible light, and has good ductility. The chemical properties of silver in precious metals are the most active. The most industrially valuable silver compounds are silver nitrate and silver halide.
Silver's thermal conductivity and electrical conductivity rank among the best in metals. Silver wire can be used to make sensitive instrument components; the important contact points of various relays are made of silver. The important components in the radio system are also soldered with silver. Various automation devices, rockets, submarines, computers, nuclear devices, and communication systems, all of which have a large number of contact points. Each contact point has to work millions of times during use. In order to withstand such rigorous work requirements, the contact points must be wear-resistant, reliable, and must meet many special technical requirements. These touch points are generally made of silver, and people are willing to use silver because it can meet all kinds of requirements. If rare earth elements are added to silver, the performance is even better. With this kind of contact point made of silver with rare earth elements, the life can be extended several times.
Silver nitrate decomposes silver when it sees light or organic matter. Silver is grayish black if it is a very small particle. This compound is used for silver plating or other silver-based compounds and is also a major raw material for the production of photographic film photosensitive layers. Silver nitrate can cause convergence, sterilization or corrosion depending on the concentration. Excessively proliferating granulation tissue can be eroded with a silver nitrate rod and its concentrated solution can be used for the treatment of conjunctivitis.
Silver oxide is easily dissolved in ammonia water, and after a long period of time, strong explosive black crystals are sometimes precipitated. Silver oxide is used as a colorant in the glass industry.
The photosensitivity of the silver bromide, the photographic film used to make the photosensitive layer.
Silver is widely distributed in nature, and it is less in a single state. It is often associated with other non-ferrous metal ores in the form of sulfide. The world's silver reserves are about 180,000 tons, and the annual output is more than 10,000 tons. China's silver ore reserves are abundant, mainly in the north of China, southern Shaanxi, southern Henan, Jixi, northern Fujian, Zhejiang and Guangdong and Guangxi, and produced 750 tons in 1993.
Silver is symbiotic with heavy metal sulfide ore such as copper , lead , zinc, etc. The main method of silver extraction is to concentrate silver in heavy metal sulfide concentrate by beneficiation , and extract it during the process of smelting these heavy metals; silver symbiotic with gold, in gold Recycling during the cyanidation process. The coarse-grained natural silver and silver-gold ore are treated by amalgamation or re-alloying-mercury. The fluorite ore and horn silver mines can be enriched by re-election or directly cyanidated. Since the silver content in the ore is higher than that in gold, and silver and silver sulfide are more difficult to cyanide than gold, silver is usually extracted with a higher concentration of cyanide solution (0.2-0.6% sodium cyanide), and the leaching time must be prolonged to increase the stirring strength. Increase the amount of inflation. Silver chloride is easier to cyanide than silver sulfide, so the silver sulfide ore is first cyanated by chlorination and then cyanidated. Manganese ore extracted from the soft silver, must first be reductive roasting, reduction of the oxide of manganese is high manganese oxide, cyanide and then, in order to reduce the consumption of the cyanating agent. The extraction of silver from anode mud is an important means of modern production of silver. In the process of smelting silver-containing copper sulfide and lead concentrate, silver is enriched in the anode slime of copper and lead electrorefining. Silver and gold are in a single state in copper and lead anode mud, or form a compound with selenium , tellurium and chlorine. Copper and lead anode mud, the silver composition varies with the raw materials processed, and the fluctuation range is large.
Ancient silver and silver alloys are used extensively for coinage and decorations. In modern times, the use of silver has strong electrical conductivity, ductility and heat transfer properties, and is used in the manufacture of parts for the electronics industry and power generation equipment. Silver is easily soluble in nitric acid or hot concentrated sulfuric acid. Silver nitrate is a colorless crystal. It is used as a disinfectant and corrosive agent in medicine due to its stability and solubility in water, and its damaging effect on organic tissues. And used to make silver halides for photosensitive materials. Silver complexes are mainly used in the silver plating industry.
Silver is one of the earliest use of metal. In some places abroad, silverware has been used in 3000 BC, and Lagash (lagcsh) has discovered silver bottles in 2800 BC. During the Spring and Autumn Period of China (8th-5th centuries BC), there was a "wrong gold and silver" process. "Shan Hai Jing", the Song Dynasty "Clouds and Bills", the Ming Dynasty "Teaching and Miscellaneous Notes" and other works have detailed the mining of silver mines and the ash-blowing method of silver smelting.