For example, the clinical manifestations of mercury poisoning include headache, dizziness, fatigue and fever. The symptoms of oral cavity and digestive tract are gingival swelling and pain, erosion and bleeding, loose teeth, pus overflowing from gingival sulcus, foul smell in oral cavity, nausea, vomiting, loss of appetite, abdominal pain and diarrhea. Red maculopapules can appear in skin contact, which are mainly distributed on limbs, head and face. A few patients may have renal damage, and some severe patients may have symptoms of acute interstitial pneumonia such as cough, chest pain, dyspnea and cyanosis. Field
Heavy metal poisoning can coagulate protein in the body, as you can see from the chemistry book of Grade Three. If you are slightly poisoned, drink a lot of milk, and the protein in the milk will react with heavy metals, so as not to damage your own body function. See a doctor immediately after drinking.
2 At present, there is no strict unified definition of what heavy metals are. In terms of environmental pollution, heavy metals mainly refer to heavy elements with obvious biological toxicity such as mercury, cadmium, lead, chromium and metalloid arsenic. Heavy metals cannot be biodegraded, on the contrary, they can be enriched by thousands of times under the biomagnification of the food chain, and finally enter the human body. Heavy metals can interact strongly with protein and enzymes in human body, making them inactive, and may also accumulate in some organs of human body, resulting in chronic poisoning.
For some reasons, heavy metal elements are discharged into rivers, lakes or oceans without treatment, or enter the soil, which makes these rivers, lakes, oceans and soils polluted and cannot be biodegraded. If fish or shellfish accumulate heavy metals and are eaten by human beings, or heavy metals are absorbed by crops such as rice and wheat and eaten by human beings, heavy metals will enter the human body and cause heavy metal poisoning, ranging from strange diseases (Minamata disease, bone pain, etc.) to severe death. Therefore, we should not eat too much seafood. We must thoroughly cook seafood before each meal to avoid eating bacteria.
question 2: what are the hazards of heavy metal cobalt to human body? It can cause symptoms of pharyngeal mucosa, followed by symptoms of gastrointestinal tract, including vomiting and abdominal cramps, elevated body temperature, weakness of calf, etc. Non-occupational contact causes polycythemia, cardiomyopathy and goiter, which can cause dermatitis. The lost cobalt has a high purity. The higher the purity, the greater the harm it may do to the human body. Cobalt is a shiny silver-gray metal, and its name comes from German, meaning "demon". Cobalt is widely distributed in nature, and it exists in the crust, ocean floor, natural water, soil, animals and plants. According to the number of neutrons contained in the elements, there are five isotopes in the cobalt element family, namely, cobalt 56, cobalt 57, cobalt 58, cobalt 59 and cobalt 6, among which all the others are radioactive except for cobalt 59, which is a stable isotope (non-radioactive). Among them, cobalt 6 is a kind of nuclear radiation element with strong penetrating power, and it is also used to treat cancer. It is generally used in industry to detect cracks and pores in thick steel, and it is a nondestructive flaw detection method. Workers should wear lead for protection when operating, and it will be fatal if they are accidentally exposed to radiation. (
Question 3: The use of metallic cobalt is mainly used to make alloys. Cobalt-based alloys are the general names of alloys made of cobalt and one or more of chromium, tungsten, iron and nickel. Tool steel containing a certain amount of cobalt can significantly improve the wear resistance and cutting performance of steel. Stellite cemented carbide containing more than 5% cobalt will not lose its original hardness even if it is heated to 1℃. Nowadays, this cemented carbide has become the most important material used between gold-containing cutting tools and aluminum. In this material, cobalt combines other metal carbide grains in the alloy composition, which makes the alloy have higher toughness and reduces the sensitivity to impact. This alloy is welded on the surface of the part, which can improve the service life of the part by 3-7 times. The most widely used alloy in aerospace technology is nickel-based alloy, and cobalt-based alloy can also be used, but the "strength mechanism" of the two alloys is different. The high strength of Ni-based alloys containing titanium and aluminum is due to the formation of phase strengthening agent with NiAl(Ti). When the operating temperature is high, the phase strengthening agent particles turn into solid solution, and the alloy soon loses strength. The heat resistance of cobalt-based alloy is due to the formation of refractory carbides, which are not easy to be converted into solid solutions and have low diffusion activity. When the temperature is above 138℃, the advantages of cobalt-based alloy are fully demonstrated. This is just right for manufacturing high-efficiency high-temperature engines, and cobalt-based alloys are just right. Using cobalt-based alloy containing 2%-27% chromium in the structural material of aviation turbine can make the material achieve high oxidation resistance without protective coating. The turbine generator with mercury as heat medium supplied by nuclear reactor can run continuously for more than one year without maintenance. It is reported that the boiler of the generator used in the United States is made of cobalt alloy. Cobalt is one of the few metals that can remain magnetic once magnetized. Under the action of heat, the temperature of losing magnetism is called Curie point. The Curie point of iron is 769℃, that of nickel is 358℃, and that of cobalt can reach 115℃. The coercivity of magnetic steel containing 6% cobalt is 2.5 times higher than that of general magnetic steel. Under vibration, general magnetic steel loses almost one third of its magnetism, while cobalt steel only loses 2%-3.5% of its magnetism. Therefore, the advantages of cobalt in magnetic materials are obvious. Cobalt metal is also widely used in electroplating, glass, dyeing, medicine and medical treatment. Lithium cobaltate made of lithium carbonate and cobalt oxide is the most widely used cathode material for high-energy batteries in modern times. Cobalt may also be used to make nuclear weapons, a theoretical atomic bomb or hydrogen bomb, which is packed in a cobalt shell and can turn cobalt into deadly radioactive dust after explosion.
Question 4: Is metal cobalt a radioactive element? Cobalt has many isotopes, and only cobalt 59 is stable and not radioactive. Others such as cobalt 6, cobalt 58 and cobalt 57 are radioactive. But there is only cobalt 59 in nature, and the usual metal cobalt is not radioactive. Radioactive cobalt is a product of artificial activation. For example, cobalt 59 is irradiated by neutrons in the reactor and becomes cobalt 6, which is radioactive.
question 5: what are heavy metals? I. heavy metals
heavy metals in chemistry
[edit this paragraph] definition
heavy metals refer to metals with a specific gravity greater than 5 (generally, metals with a density greater than 4.5 grams per cubic centimeter). There are about 45 species, which are generally transitional elements. Such as copper, lead, zinc, iron, cobalt, nickel, manganese, cadmium, mercury, tungsten, molybdenum, gold and silver. Although heavy metals such as manganese, copper and zinc are trace elements needed for life activities, most heavy metals such as mercury, lead and cadmium are not necessary for life activities, and all heavy metals are toxic to human body if they exceed a certain concentration.
For example, the clinical manifestations of mercury poisoning are: headache, dizziness, fatigue and fever. The symptoms of oral cavity and digestive tract are gingival swelling and pain, erosion and bleeding, loose teeth, pus overflowing from gingival sulcus, foul smell in oral cavity, nausea, vomiting, loss of appetite, abdominal pain and diarrhea. Red maculopapules can appear in skin contact, which are mainly distributed on limbs, head and face. A few patients may have renal damage, and severe patients may have symptoms of acute interstitial pneumonia such as cough, chest pain, dyspnea and cyanosis.
Heavy metal poisoning can coagulate protein in the body, which you can see from the chemistry book of Grade Three. Drink plenty of milk if you are slightly poisoned. Protein in milk will react with heavy metals. This will not damage your own physical function. You must see a doctor immediately after drinking it.
At present, there is no strict and unified definition of heavy metals. In terms of environmental pollution, the heavy metals mainly refer to heavy elements with obvious biological toxicity such as mercury, cadmium, lead, chromium and metalloid arsenic. Heavy metals cannot be biodegraded, on the contrary, they can be enriched by thousands of times under the biomagnification of the food chain, and finally enter the human body. Heavy metals can interact strongly with protein and enzymes in human body, making them inactive, and may also accumulate in some organs of human body, resulting in chronic poisoning. Heavy metal elements are discharged into rivers, lakes or oceans without treatment for some reasons, or enter the soil, which makes these rivers, lakes, oceans and soils polluted and they cannot be biodegraded. If fish or shellfish accumulate heavy metals and are eaten by human beings, or heavy metals are absorbed by crops such as rice and wheat and eaten by human beings, heavy metals will enter the human body and cause heavy metal poisoning, ranging from strange diseases (Minamata disease, bone pain, etc.) to severe death. Therefore, we should not eat too much seafood. We must thoroughly cook seafood before each meal to avoid eating bacteria.
question 6: is chromium a heavy metal? yes, it belongs to heavy metal in a broad sense.
metals with a density above 4.5g/cm3 are called heavy metals. There are 6 kinds of natural metal elements with atomic numbers from 23(V) to 92(U), and the relative densities of the other 54 kinds are all greater than 4.5g/cm3, so these 54 kinds of metals are all heavy metals in the sense of relative density. However, in the classification of elements, some of them belong to rare earth metals, while others belong to refractory metals. In the end, 1 metal elements are really classified as heavy metals in industry: copper, lead, zinc, tin, nickel, cobalt, antimony, mercury, cadmium and bismuth. These 1 kinds of heavy metals have no special * * * properties except that they are metallic and have a density greater than 5. All kinds of heavy metals have their own properties.
Question 7: Cobalt is a hard metal with steel gray and metallic luster. Cobalt (Co) has an atomic number of 27 and an atomic weight of 58.93. Its main physical and chemical parameters are close to those of iron and nickel, and it belongs to the iron group. Cobalt is a magnetic hard metal with high melting point and good stability. Its Curie point (critical temperature point for loss of magnetism) is 115℃, it is permanent, its melting point is 1495℃, its boiling point is 29℃, and it has high temperature resistance. It is an important raw material for making heat-resistant alloys, hard alloys, corrosion-resistant alloys, magnetic alloys and various cobalt salts, and is widely used in aviation, aerospace, electrical appliances, machinery manufacturing, chemistry and ceramic industries. Therefore, it is an important strategic material. The natural reserves of cobalt in the crust are 13 million tons, and the exploitable reserves are 7 million tons. In addition, there are millions of tons of ore deposits and deep seabed. In 24, the world's cobalt production was 52,4 tons, including 16, tons in Congo, 1, tons in Zambia, 6,7 tons in Australia, 5,2 tons in Canada and 4,7 tons in Russia. The amount of cobalt metal resources in China is about 1.4 million tons, most of which are associated resources, and there are few individual cobalt deposits. Cobalt ore in China has a low grade, which is recovered as a mine by-product. Due to the low grade and complicated production process, the metal recovery rate is low and the production cost is high. In 1996, the output of cobalt metal (cobalt content) in China was 229t, the output of cobalt sulfur concentrate (cobalt content) was 192t, and cobalt oxide was 638t t. In recent years, the annual consumption of cobalt in China has stabilized at about 1,2 t, and the domestic cobalt production, including cobalt oxide, is about 6 ~ 7 t per year. The domestic cobalt production can not meet the domestic demand, and about half of it needs to be imported every year. The physical and chemical properties of cobalt determine that it is an important raw material for producing heat-resistant alloys, cemented carbides, corrosion-resistant alloys, magnetic alloys and various cobalt salts. Cobalt-based alloys or cobalt-containing alloy steels are used as blades, impellers, ducts, jet engines, rocket engines, missile components, various high-load heat-resistant components in chemical equipment and important metal materials in the atomic energy industry. As a binder in powder metallurgy, cobalt can ensure the toughness of cemented carbide. Magnetic alloy is an indispensable material in modern electronics and electromechanical industry, which is used to manufacture various components of acoustic, optical, electrical and magnetic equipment. Cobalt is also an important part of permanent magnetic alloys. In the chemical industry, cobalt is not only used in superalloys and anticorrosion alloys, but also used in colored glass, pigments, enamels, catalysts and desiccants. According to the British "Metal Herald" report, the demand for cobalt from the hard metal sector and superalloys is relatively strong recently. In addition, the consumption growth rate of cobalt in the battery sector is the highest. According to domestic reports, the application of cobalt in battery industry, diamond tool industry and catalyst industry will be further expanded, thus the demand for metallic cobalt is on the rise. Separate cobalt deposits are generally divided into three types: cobalt arsenide deposits, cobalt sulfide deposits and cobalt clay deposits. In addition to individual deposits, cobalt is widely dispersed in skarn-type iron ore, vanadium-titanium magnetite, hydrothermal polymetallic ore, various types of copper ore, deposited cobalt-manganese ore, copper-nickel sulfide ore, nickel silicate ore and other deposits. Although its grade is low, its scale is often large, which is the main source of cobalt extraction. There is no unified regulation on the evaluation index of associated cobalt in comprehensive deposits. Generally, the grade of cobalt in ores with good metallurgical properties is more than .1%. Cobalt concentrate with a grade of .2% is valuable. If the metal deposit is large in scale and the comprehensive recovery effect of ore is good, how much cobalt is there? Cobalt-sulfur concentrate is divided into six grades according to chemical composition, all of which are calculated according to dry ore grade. The application of cobalt minerals has a long history. The Egyptians used cobalt blue as a colorant for ceramic products before the era, and China has also widely used cobalt compounds as colorants in ceramic production since the Tang Dynasty. Cobalt was first isolated by Swedish chemist Brandt in 1735 and identified as an element by Bergman in 178. Germany and Norway first produced a small amount of cobalt, and in 1874, the cobalt oxide mine in New Caledonia was developed. In 193, the production of silver cobalt ore and arsenic cobalt ore (skutterudite) in northern Ontario, Canada began, which made the world output of cobalt soar from 16t in 194 to 1553t in 199. After the development of copper-cobalt ore belt in Katanga province, Zaire in 192, the output of cobalt has been ranked first in the world. Morocco used arsenic-cobalt ore to produce cobalt, and during this period, it mainly produced cobalt by pyrometallurgy. After that, on the eve of World War II, Finland extracted cobalt from pyrite cinder containing cobalt, and sent it to West Germany for chlorination and roasting after the war. It was not until 1968 that kokkola Cobalt Factory was established. Japan, France and Belgium have > >