The most important thing is the weapon system, electronic night vision device? Is it a lot? How about an example? If the high-end weapon system has no rare earth components? Just as we stir-fry without salt or ingredients, even the best dishes are not delicious without salt and ingredients. The following is a reference. Rare is rare in English. Soil means "rare soil". In fact, this is just a misunderstanding left over from the18th century. After 1787, several rare earth elements were discovered one after another, but few corresponding minerals were found. Due to the limitation of science and technology at that time, people could only produce some oxides as impure as soil, so people left such a unique and interesting name for this group of elements.

According to the definition of rare earth elements by the International Union of Pure and Applied Chemistry, rare earth elements are lanthanides with atomic number 57-7 1 in the third subgroup of Mendeleev's periodic table. That is, lanthanum (57), cerium (58), praseodymium (59), neodymium (60), promethium (6 1), samarium (62), europium (63), gadolinium (64) and terbium (3). Except scandium and promethium, other 15 elements are Chang Shengcheng.

According to the differences of physical and chemical properties and geochemical properties between rare earth elements and the requirements of separation process, scholars often divide rare earth elements into light, heavy or light, medium and heavy groups. The division of the two groups is based on gadolinium. Seven elements before gadolinium, namely lanthanum, dysprosium, cerium, praseodymium, neodymium, promethium, samarium and europium, are light rare earth elements, also known as cerium group rare earth elements. After gadolinium and gadolinium, nine elements such as terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium and yttrium are called heavy rare earth elements, also known as yttrium rare earth elements. Although the atomic weight of yttrium is only 89, its chemical properties are closer to those of heavy rare earth elements because its ion radius is in the ion radius chain of other heavy rare earth elements. In nature, it also appears with other heavy rare earth elements. Therefore, it is classified as a heavy rare earth group. There are no certain rules for the classification of light, medium and heavy rare earths. According to the solubility of rare earth sulfate double salt, it can be divided into: insoluble cerium group is light rare earth group, including lanthanum, cerium, praseodymium, neodymium and samarium; The insoluble terbium family is a medium rare earth family, including europium, gadolinium, terbium and dysprosium; The more soluble yttrium group is the heavy rare earth group, including yttrium, holmium, erbium, thulium, ytterbium and lutetium. However, the solubility difference of each group of adjacent elements is very small, so it is not clear by this method. At present, the extraction method is commonly used to group. For example, using bis (2) ethylhexyl (phosphoric acid), P204 can be grouped between neodymium and samarium, and then between gadolinium and terbium. Lanthanum, cerium, praseodymium and neodymium are called light rare earths, samarium, europium and gadolinium are called medium rare earths, and terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium plus yttrium are called heavy rare earths.

The content of rare earth in the earth's crust is not uncommon. The Clark value of this group of elements is 0.0236%, including 0.0 1.592% for cerium group and 0.0077% for yttrium group. It is more than common elements such as copper (0.0 1%), zinc (0.005%), tin (0.004%), lead (0.00 16%), nickel (0.008%) and cobalt (0.003%). This group of elements is not soil, but a group of typical metal elements, whose activity is second only to alkali metals and alkaline earth metals.

Table 1- 1? Abundance of rare earth elements in the crust

Yuan? Sue? Name? Say/make a phone call

scandium (Sc)

Y

The sixth note of the major scale

cerium (Ce)

praseodymium (Pr)

neodymium (Nd)

Prime minister

samarium (Sm)

Crustal abundance, ppm

25

3 1

35

66

9. 1

40

4.5* 10- 1

7.06

Yuan? Sue? Name? Say/make a phone call

europium

gadolinium

Trillion byte

dysprosium (Dy)

ah

hum

thulium (Tm)

ytterbium (Yb)

lutecium (Lu)

Crustal abundance, ppm

2. 1

6. 1

1.2

4.5

1.3

1.3

0.5

3. 1

0.8

The position of rare earth elements in the periodic table is very special. The element 17 belongs to ⅲ b group, and scandium, yttrium and lanthanum are the first elements in the fourth, fifth, sixth and long-period transition elements series respectively. Lanthanum is very similar to the following element 14 in nature, and chemists can only put them in one lattice. No wonder some people regard them as "isotopes", but because of their different atomic numbers, they can't be counted as real isotopes. That is to say, their properties are similar, but they are not exactly the same, which brings difficulties to the separation of this group of elements, but it also shows that separation is possible as long as they make use of their subtle differences; On the other hand, their electronic structure has an internal electronic layer that is not completely filled, that is, a 4f electronic layer. Because of the different number of electrons in the 4f layer, each element in this group has a very special personality, especially optical and magnetic properties, just like a piano with a complete keyboard and a wide range.

Information, biology, new materials, new energy, space and ocean are pushed into six new science and technology groups by contemporary scientists. People attach importance to, research and develop rare earths because rare earth elements have their own fields in these six science and technology groups. However, after all, rare earth elements are still a group of elements that have not been fully understood by people, and we need to make great efforts to study and understand them, so as to support them and make them make greater contributions to mankind.

Rare earth is not a mineral, but a rare mineral. Rare earth elements include 17, namely lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, etc. As early as 1787, chemists discovered several rare earth elements one after another, but few corresponding minerals were found, so chemists called these substances rare earths. Of course, the rarity of rare earth elements is relative. The geological survey results in recent years show that rare earth elements are quite abundant in the earth's crust, such as cerium higher than cobalt, yttrium higher than lead, and lutetium and thulium equivalent to antimony, mercury and silver.

However, it is very difficult to separate rare earth elements because they are usually concentrated in the earth's crust and their physical and chemical properties are similar. Therefore, the purification of rare earth elements is a great difficulty in chemical research. Yttrium was separated from Finn Gardolin in 1794, and promethium was made by Malinschi and others in the United States in 1947. The complete purification of 17 rare earth elements has gone through 150 years. Academician Xu Guangxian's important contribution is also in the field of rare earth extraction. He put forward the theory of cascade extraction, which improved the extraction and separation technology of rare earths in China to the international advanced level.

China ranks first in the world in rare earth resources.

China is rich in rare earth mineral resources with superior metallogenic conditions, and its proven reserves rank first in the world, which provides a solid foundation for the development of rare earth industry in China. There are about 250 kinds of rare earth minerals found in the world, but only 50 ~ 60 kinds of rare earth minerals have industrial value, and only about 10 kinds have mining value at present. In addition to China, countries with rare earth resources in the world include the United States, Russian Federation, Canada and Australia.

China's rare earth resources account for 4 1.36% of the world, and its distribution is extremely reasonable, so it is a veritable country with rare earth resources. The main rare earth mines in China are Bayanobo rare earth mine, Shandong Weishan rare earth mine, Mianning rare earth mine, Jiangxi weathering crust leaching rare earth mine, Hunan brown yttrium mine and coastal long coastline placer mine. At present, the high-purity rare earth produced in China accounts for more than 80% of the world output.

Rare earths are widely used in life.

We deal with rare earth materials every day, because the computers and televisions we often use contain rare earth materials. Because rare earth elements have a special electronic shell structure, they can convert the absorbed energy into light and emit it, so rare earth elements can be used to make phosphors in electronic picture tubes. CRT phosphor contains rare earth elements yttrium and europium, and its application effect is far better than that of non-rare earth sulfide red phosphor used before. At present, various rare earth phosphors are widely used, such as radar picture tubes, fluorescent lamps and high-pressure mercury lamps.

Rare earth oxides can also be used to make special glasses. For example, the glass containing rare earth element lanthanum is a kind of glass with excellent optical properties, high refractive index, low dispersion and good chemical stability, which can be used to manufacture lenses of advanced cameras and periscope. Rare earth oxides can also be used to make colored glass. Adding rare earth element Nd can make the glass wine red, adding rare earth element Pr can make the glass green, and adding rare earth element Er can make the glass pink. These stained glasses are unpredictable in color and can be used as decorations.

Rare earth elements can also play an important role in protecting our health. Rare earth compounds can be used to stop bleeding, and the hemostasis effect is rapid and can last for about one day. The use of rare earth drugs has a good effect on dermatitis, allergic dermatitis, gingivitis, rhinitis and phlebitis. For example, the use of rare earth drugs containing cerium salts can reduce the inflammation of burn wounds and accelerate healing. The anticancer effect of rare earth elements has aroused widespread concern. Rare earth elements can not only eliminate harmful free radicals in the body, but also reduce the level of calmodulin in cancer cells and improve the level of tumor suppressor genes.

In addition to the above three uses, rare earth elements are also widely used in our lives. As long as the right amount of rare earth elements are added to some traditional products, some magical effects will be produced. At present, rare earths have been widely used in dozens of industries such as metallurgy, petroleum, chemical industry, textile, medicine and agriculture. For example, rare earth steel can significantly improve the wear resistance, corrosion resistance and toughness of steel; Rare earth aluminum wire can improve the strength and conductivity while reducing the fineness of aluminum wire; Spraying rare earth pesticides on fruit trees can not only eliminate pests and diseases, but also improve the fruit hanging rate; Rare earth compound fertilizer can not only improve soil structure, but also increase the output of agricultural products; The cost of rare earth oil cracking catalyst used in China oil refining industry is less than 10 billion yuan, but it can improve the output efficiency of gasoline and other light oil for many times.

And as you may know, liquid crystals and warheads, as well as China, have the largest reserves. ?

In fact, the United States did not tell everyone their real purpose: emerging energy! ?

Rare earth and energy are impossible? If you don't believe me, just watch what I say. ?

I guess: Rare earth, a rare metal alloy material, is an undeformed superhard material with high temperature and pressure resistance, and is an important raw material for manufacturing semi-solid energy engine cylinder blocks and accessories. This is the secret of America. They call this kind of engine "knock engine", which is the top secret technology of the United States. Everyone envies the high speed of flying saucers, which is the guarantee of instant power. When the plane is overtaken by a missile, it can start a thin jet engine to accelerate out of the missile's killing range. In the ultra-high altitude hypoxia environment, it is a near-earth application technology of near-space technology, an anaerobic non-rocket flight technology, and rare earth is the key raw material of this technology. ?

In Rare Earth, it is very vivid that some rare element alloys in rare earth are accompanied by sensitive and fickle things, and their sensitivity to temperature is beyond imagination. A small temperature difference can change their physical and chemical properties. This is the discovery of * *, and now some temperature difference technologies have been published, but the actual core temperature difference technology is not mentioned at all, that is, the temperature difference generator technology: 1. Liquid technology. 2. Solidify this technology, combine with temperature memory technology, and use temperature difference to generate deformation and power. Make the generator work to generate electricity or run the engine. So as long as the sun rises and sets, * * will never lack motive energy, not perpetual motion machine or nuclear fission, but real future new energy technology. Unfortunately, only China has a large amount of this raw material, which is called "earth". So I can't tell you the real use of rare earths. In fact, its strategic value is no less than that of nuclear mines! ?

China has natural resources, but it wastes them. No waste of human resources, no waste of technical resources, no waste of resources left by ancestors! ?

"There is oil in the Middle East and rare earth in China." This is ** 1992 when the southern tour arrived in Jiangxi. However, from 1990 to 2005, the export volume of rare earths in China increased by nearly 10 times, but the average price decreased by 60%. ? In 20 10, the country greatly reduced the export of rare earths.

The following are the military uses of rare earths: Why is it easier for Patriot missiles to shoot down Scud? Why does the American M 1 always fire earlier and hit more accurately, although the direct distance between the main gun of the American M 1 and the Soviet T-72 tank is not much different? Why can F-22 fighters cruise at supersonic speed? ……

These "why" outlines the great progress of military science and technology today, and also outlines the turmoil and conflicts in the world in the past 20 years. For every "why", there is a specific and clear answer. But from the perspective of materials science, "rare earth" can solve all the above problems at one time.

In recent decades, the development and application of rare earths have provided a powerful engine for military science and technology.

The incredible military miracles in the Gulf War and the asymmetric control ability of the US military in local wars after the Cold War, in a sense, are all caused by rare earths.

Because of this, the development and utilization of rare earths are also pregnant with great dangers. On the one hand, more and more countries and military forces participate in the competition and research and development of rare earths in order to gain asymmetric control over their opponents, which breeds the risk of an arms race; On the other hand, countries that have acquired this ability are more inclined to solve disputes through threats or wars. In this regard, China, as the country with the largest reserves of rare earths in the world, needs to cool down the arms race from the source, strictly limit the exploitation of rare earths and immediately ban the export of rare earths.

In fact, the China government pays little attention to the development of rare earths. As early as 1950s, Premier Zhou Enlai included the development of rare earths in China's first scientific and technological development plan. 1975 China established a leading group for rare earths. Although the organization of the State Council has been adjusted, the specialized management organization of rare earth industry has been retained. 199 1 year, rare earth is listed as a national protected mineral. In terms of rare earth protection policy, even China Petroleum has no such treatment, with specialized institutions, stable industrial policies and consistent overall control by the state. However, the achievements of the rare earth industry in the past decades have basically stayed at the low level of selling resources. With regard to the current situation of rare earth production, the Ministry of Land and Resources has carried out many times of cleaning-up for problems such as indiscriminate mining and excavation, overcapacity and disorder since 1999. Measures taken include total control, blowing up illegal mines, confiscating production equipment, judicial intervention, licensing, signing letters of responsibility with grass-roots governments, signing contracts with mines, etc ... In 2005, the Ministry of Commerce began to control rare earth exports with taxes. These measures are strong and last for a long time, almost reaching the power limit of the management department.

However, chaos still exists. Someone once concluded that there are seven mysteries of rare earth in China: 1. Industrial policy-oriented macro-control has been difficult to work; 2. The policy of adjusting industrial structure and controlling total production failed again and again; 3. Sustainable development and mining cannot be implemented; 4. Strengthening management measures based on unified planning are difficult to implement; 5. The desire to promote industrial upgrading through technological innovation is always just a wish; 6. The countermeasures of realizing industry self-discipline through joint restructuring are impossible to start; 7. The goal of strengthening popularization and application to increase the added value of products has not been achieved so far.

In this chaos, the exploitable reserves of rare earths in China have decreased from 80% in the world more than ten years ago to 52% now. If we continue the current production and operation mode, China will become a small country with rare earths in 20 to 50 years. If one day, China realizes the value of rare earth and wants to buy it from the world, it will be sky-high for China.

Oxides of rare earth elements

Make weapons more cold-blooded

Rare earth is related to world peace and national security in strategic metals. Why can Patriot missiles destroy Scud missiles more easily? This is due to the excellent work of the front precision guidance system. In its guidance system, about 4kg of Sm-Co magnets and nd-Fe-B magnets are used for electron beam focusing, and Sm and Nd are rare earth elements. M 1 why can tanks find the enemy first? Because the tank is equipped with Nd-doped yttrium aluminum garnet laser rangefinder, it can reach the sight distance of nearly 4000 meters in sunny days, while the T-72 laser rangefinder can see 2000 meters. At night, the night vision device containing rare earth element lanthanum became a nightmare for the Iraqi army.

As for the function of F-22 supersonic cruise, thanks to its powerful engine and light and solid fuselage, a large number of special materials made of rare earth technology are used. For example, F 1 19 engine blades and combustion chambers are made of flame-retardant titanium alloy, which is said to be made of rhenium; The fuselage of the F-22 is armed with magnesium-titanium alloy strengthened with rare earth. Otherwise, in supersonic cruise, F 1 19 is strong enough to destroy itself.

All of the above are just a glimpse of the whole leopard. In fact, almost all weapons that can be called high-tech have no rare earth; More deadly, rare earths are often concentrated in the most critical parts, which degenerates these weapons into magic. Like what? In addition to the guidance system, "Patriot" also uses rare earth alloys in key parts such as the control wing surface of the missile body; The armor of some advanced tanks has better bulletproof performance after using rare earth materials; The "Clairvoyance" and "Clairvoyance" that control the battlefield situation in the United States also have high-power traveling wave tubes made of rare earth technology, which makes them more reliable and more anti-jamming. ...

In a word, compared with traditional weapons, high-tech weapons are more convenient, sensitive, accurate and easy to operate. These are easy to mention, but they embody many of the highest achievements in materials science, electronic science and engineering manufacturing. These achievements are often due to the discovery and application of some special functions of rare earths.

Rare earths are called "vitamins" in industry. Because of its excellent physical properties such as optoelectromagnetism, it can be combined with other materials to form a wide variety of new materials with different properties. Its most significant function is to greatly improve the quality and performance of other products. For example, the tactical performance of steel, aluminum alloy, magnesium alloy and titanium alloy used to manufacture tanks, planes and missiles will be greatly improved. Moreover, rare earth is also a lubricant for electronics, lasers, nuclear industry, superconductivity and many other high technologies. Once rare earth technology is used in the military, it will inevitably bring about a leap in military technology. In a sense, the overwhelming control of the US military in several local wars after the Cold War and its ability to openly kill the enemy without scruple stem from its advantages in the field of rare earth science and technology.