The use of the phenomenon of superconductivity opens up wide possibilities in technology. Sources of powerful constant magnetic fields in the form of solenoids with windings made of superconducting materials are widely used. Work is underway to use superconductors for power lines and many other electrical devices.

Of all the elements capable of transitioning to the superconducting state, niobium has the highest critical transition temperature of 9.17 K (-263.83 ° C). Superconducting alloys with a high niobium content have found practical use: 65BT and 35BT (GOST 10994-74). Alloy 65BT contains 22-26% Ti; 63-68% Nb; 8.5-11.5% Zr and has a critical transition temperature of 9.7 K (-263.3 C). For T = 4.2 K, the critical values ​​of the current density are 2.8·106 A/m2, the magnetic field strength is (6-7.2)·106 A/m. Wire made of alloy 35BT with composition 60-64% Ti; 33.5-36.5% Nb; Due to increased fragility, 1.7-4.3% Zr is poured into a copper matrix.

Both alloys are used for windings of powerful generators and magnets high power(for example, magnetic levitation trains), tunnel diodes (for computers).

The ability of superconductors, which are diamagnetic, to push out a magnetic field, is used in magnetic pumps that allow generating magnetic fields colossal tension, as well as in cryogenic gyroscopes. The gyroscope armature, made of a superconductor, “floats” in a magnetic field. The absence of supports and bearings eliminates friction and increases the durability of the gyroscope.

Significant progress has been made in obtaining high-temperature superconductivity. Based on metal ceramics, for example, the composition YBa2 Cu3 Ox, substances have been obtained for which the temperature Tc transition to the superconducting state exceeds 77 K (nitrogen liquefaction temperature).

The phenomenon of superconductivity is used to produce strong magnetic fields, since there is no heat loss when strong currents pass through a superconductor, creating strong magnetic fields. However, due to the fact that the magnetic field destroys the state of superconductivity, so-called magnetic fields are used to obtain strong magnetic fields. Type II superconductors, in which the coexistence of superconductivity and a magnetic field is possible. In such superconductors, a magnetic field causes the appearance of thin threads of normal metal that penetrate the sample, each of which carries a magnetic flux quantum. The substance between the threads remains superconducting.

There are photon detectors based on superconductors. Some use the presence of a critical current, they also use the Josephson effect, Andreev reflection, etc. Thus, there are superconducting single-photon detectors (SSPD) for recording single photons in the IR range, which have a number of advantages over detectors of a similar range (PMTs, etc.) using other registration methods.

The smallest superconductor was created in 2010 based on the organic superconductor (BETS)2 GaCl4, where the abbreviation BETS stands for bisethylene dithiotetraselenafulvalene. The created superconductor consists of only four pairs of molecules of this substance at total length sample is about 3.76 nm.

Option 14. Assignments for the Unified State Exam 2018. Russian language. I.P. Tsybulko. 36 options

Read the texts and complete tasks 1 - 3

(1)Superconductors are used to create devices that are technically or economically impossible

It is unprofitable to manufacture using traditional conductor materials - copper and aluminum. (2)<...>

powerful magnetic systems for thermonuclear fusion facilities or particle accelerators,

ultra-fast current limiters, medical tomographs, high-resolution spectrometers, samples

promising military equipment, magnetic levitation trains are created using superconducting materials.

(3)Devices made using superconducting materials are characterized by significantly

smaller in size and weight.

1. Indicate two sentences that correctly convey the MAIN information contained in the text. Write it down

numbers of these offers.

1) To create devices that are impossible or unprofitable to manufacture using conventional

conductors, superconductors are used to help make these devices more compact and lighter.

2) When creating powerful magnetic systems for thermonuclear fusion installations or elementary accelerators

particles, ultra-fast current limiters, medical tomographs, high-resolution spectrometers,

samples of promising military equipment, magnetic levitation trains sometimes use superconducting

3) To create structures that are impractical to construct using only traditional conductors

materials - copper and aluminum, superconductors are also used.

4) Superconductors are used to create devices that cannot be made from conventional conductors

or economically unprofitable, and the use of superconductors makes devices less voluminous and less

heavy.

5) For the manufacture of devices that must have a small volume and weight with a variety of

the functions they perform, they use conductors.

2. Which of the following words (combinations of words) should appear in the blank in the second (2) sentence

text? Write down this word (combination of words).

On the contrary, Despite this, For example, Since Nevertheless

3. Read a fragment of a dictionary entry that gives the meaning of the word MASS. Determine the value in

in which this word is used in the third (3) sentence of the text. Write down the number corresponding to this value

in the given fragment of the dictionary entry.

MASS, - s, f.

1) A collection of something, as well as something large, concentrated in one place. Air masses. Dark

m. building.

2) One of the main physical characteristics of matter, determining its inert and gravitational properties.

Unit of mass.

3) Dough-like, shapeless substance, thick mixture. Wood pulp (semi-finished product for making paper).

Molten m. cast iron.

4) Many, a large number of someone or something. I have m. time. Spend a lot of energy.

5) plural Broad sections of the working population. The will of the masses. Break away from the masses (lose contact with the people).

4. In one of the words below there was an error in the placement of the accent: the letter was highlighted INCORRECTLY,

denoting a stressed vowel sound. Write this word down.

Flint is surrounded, etc., and Wholesale has departed.

5.In one of the words below the highlighted word is used INCORRECTLY word. Correct a lexical error,

choosing a paronym for the highlighted word. Write down the chosen word.

Issues of various applications of superconducting materials began to be discussed almost immediately after the discovery of the phenomenon of superconductivity. Kamerlingh Onnes also believed that with the help of superconductors it was possible to create economical installations for producing strong magnetic fields. However, the real use of superconductors began in the 50s and early 60s of the 20th century. Superconducting magnets of various sizes and shapes are currently in use. Their use has gone beyond the scope of purely scientific research, and today they are widely used in laboratory practice, in accelerator technology, tomographs, and installations for controlled thermonuclear reactions. With the help of superconductivity, it has become possible to greatly increase the sensitivity of many measuring instruments. Such devices are called squids(from English Superconducting Quantum Interference Devices). Particular attention should be paid to the introduction of SQUIDs into technology, including modern medicine.

Superconductors are currently most widely used in the field of creating strong magnetic fields. Modern industry produces a variety of wires and cables from type II superconductors, which are used to make windings of superconducting magnets, which produce significantly stronger fields (more than 20 Tesla) than when using iron magnets.

Superconducting magnets are also more economical. So, for example, to maintain a field of 100 kG in a copper solenoid with an internal diameter of 4 cm and a length of 10 cm, an electrical power of at least 5100 kW is required, which must be completely removed by water cooling the magnet. This means that at least 1 m 3 of water per minute must be pumped through the magnet, and then cooled further. In the superconducting version, such a volume of magnetic field is created quite simply; it is only necessary to construct a helium cryostat to cool the windings, which is a simple technical task.

Another advantage of superconducting magnets is that they can operate in a short-circuited mode, where the field is “frozen” in the volume, providing virtually time-independent field stability. This property is very important when studying substances using nuclear magnetic and electron paramagnetic resonance methods, in tomographs, etc.

Another application of superconductors is the creation of bearings and supports without friction. If a superconducting sphere is placed above a metal ring with current, then a superconducting current is induced on its surface due to the Meissner effect, which leads to the appearance of repulsive forces between the ring and the sphere, and the sphere can hang above the ring.


A similar effect can be observed if a permanent magnet is placed above a superconducting ring. This may be the basis for the creation, for example, of new modes of transport. We are talking about creating a magnetic levitation train in which there will be completely no losses due to friction on the road track. A 400 m long model of such a superconducting road was built in Japan back in the 1970s. Calculations show that a magnetic levitation train will be able to reach speeds of up to 500 km/h. Such a train will “hover” above the rails at a distance of 2-3 cm, which will give it the opportunity to accelerate to the specified speeds.

Currently, superconducting cavity resonators are widely used, the quality factor of which can reach . On the one hand, such devices make it possible to obtain high frequency selectivity. On the other hand, superconducting resonators are widely used in superconducting accelerators, making it possible to significantly reduce the power required to create an accelerating electric field.

The use of superconductivity can lead to the creation of ultra-fast electronic computers. We are talking about so-called cryotrons - switching superconducting elements. Such devices can be easily combined with superconducting memory elements. An important advantage What makes cryotrons superior to conventional semiconductor devices is the lack of steady-state energy requirements. After the creation of Josephson junctions, it was proposed to replace cryotrons with them, and it turned out that the switching time of such a system is about 10 -12 s. This is precisely what opens up broad prospects for the creation of powerful computers, but so far these developments are only laboratory samples.

Cryoenergetics and cryoelectronics are considered the most promising areas for the widespread use of high-temperature superconductors. Cryoenergetics has already developed a method for manufacturing fairly long (up to several kilometers) wires and cables based on bismuth HTSC materials. This is already enough for the manufacture of small motors with superconducting windings, superconducting transformers, inductors, etc. Based on these materials, superconducting solenoids have been created that provide magnetic fields of the order of 10,000 Gauss at liquid nitrogen temperature (77 K).

In cryoelectronics, a technique has been developed for the production of film SQUIDs, which in their characteristics are practically not inferior to their helium analogues. A technique has been mastered for producing perfect magnetic screens from HTSC, in particular, for studying biomagnetic fields. Antennas, transmission lines, resonators, filters, frequency mixers, etc. are created from HTSC.

The pace of technological and applied research is very high, so it is possible that industry will master the production of products from high-temperature superconductors before the nature of superconductivity in metal-oxide compounds is reliably clarified.

Control questions

1. What is the equilibrium state of the electron gas in a conductor in the absence of an electric field?

2. Explain the mechanism of electron drift under the influence of an external field.

3. What relationships determine the mobility of charge carriers in semiconductors? What factors determine the amount of mobility?

4. What determines the electrical conductivity σ n of metals?

5. What causes the electrical resistance of metals? What is its dependence on temperature?

6. What does the Wiedemann-Franz law say?

7. Why is the total concentration of charge carriers taken into account when calculating the electrical conductivity of conductors, if in reality only Fermi electrons participate in conductivity?

8. Provide a graph and explain the dependence of the conductivity of a doped semiconductor with different degrees of doping on temperature.

9. Indicate the basic properties of the superconducting state

10. Give a qualitative description of the mechanism of superconductivity using the BCS theory.

11. Describe the areas of application of superconductivity.

Option 14 (USE-2015) Part 1 Read the text and complete tasks 1-3. (1) While studying starfish larvae under a microscope, Ilya Ilyich Mechnikov discovered that they contained mobile cells that not only participated in digestion, but also performed protective functions, which was confirmed by experiments: having introduced a rose thorn into the body of a transparent larva, Mechnikov saw how these cells moved towards him and soon surrounded the thorn from all sides. (2) The scientist called them phagocytes and suggested that similar cells exist in all living organisms, including humans: when harmful microbes enter the body, phagocytes rush to fight them and, destroying and digesting them, die themselves. (3)<...>This discovery and many years of research led Mechnikov to the creation of the theory of immunity. 1. Which of the following sentences correctly conveys the MAIN information contained in the text? 1) Experiments with transparent starfish larvae led Mechnikov to the discovery of phagocytes in these organisms - mobile cells that not only participate in digestion, but also perform protective functions. 2) Motile cells discovered by Mechnikov while studying starfish larvae, which he called phagocytes, can rush to fight microbes and also participate in digestion. 3) The assumption put forward by Mechnikov that the cells involved in the digestion process - phagocytes - are found in all living organisms, was confirmed by the scientist’s research conducted over many years. 4) While studying starfish larvae, Mechnikov discovered cells with protective functions, which he called phagocytes, and many years of research on these cells in living organisms led the scientist to the creation of the theory of immunity. 5) As a result of many years of research in living organisms of cells with protective functions, discovered during the study of starfish larvae and called phagocytes, Mechnikov created the theory of immunity. 2. Which of the following words (combinations of words) should appear in the gap in the third (3) sentence of the text? Write down this word (combination of words). Unfortunately But on the contrary Despite this In the future 3. Read a fragment of a dictionary entry that gives the meaning of the word FUNCTION. Determine the meaning in which this word is used in the first (1) sentence of the text. Write down the number corresponding to this value in the given fragment of the dictionary entry. FUNCTION, -i, g. 1) Responsibility, range of activities. Service functions. Functions of the trade union committee. 2) Role, meaning of something. Functions of credit. 3) Work carried out by an organ, an organism. Function of the glands. 4) In mathematics: a law according to which each value of a variable (argument) is associated with a certain specific quantity. Linear function(changing in direct proportion to the change in its argument). 5) In philosophy: a phenomenon that depends on another and changes as this other phenomenon changes. 4. In one of the words below, an error was made in the placement of stress: the letter denoting the stressed vowel sound was highlighted incorrectly. Write down this word occupied Began more beautiful than accountants faucets 5. In one of the sentences below, the highlighted word is used INCORRECTLY. Correct the mistake and write the word correctly. First a sharp cough was heard in the telephone receiver, then a hoarse voice, accompanied by DIFFICULT breathing. The athletes, tensely awaiting the judges' decision, could hear snippets of irritated statements from upset fans. Just a few years ago it was impossible to PAY for cellular services using a mobile phone. Classmates did not expect that Alexey would put forward such a GREAT proposal, which many people wanted to implement. “It’s hot today, let’s organize games by the pool,” the young teacher suggested to the counselors, putting a bright Panama hat on the smiling baby. 6. In one of the words highlighted below, an error was made in the formation of the form. Correct the mistake and write the word correctly. make yourself MORE COMFORTABLE a few CHERRIES LIE on the couch THE SHORTEST route with EIGHTY deputies 7. Establish a correspondence between the proposals and those admitted to them grammatical errors: for each position in the first column, select the corresponding position from the second column SENTENCES A) I.S. Turgenev wrote about language that “handle this powerful weapon with respect.” B) All graduates composed several poetic lines and read them at the last bell celebration dedicated to their favorite school. C) None of the friends could even imagine that an innocent prank, as it seemed at first, would lead to such unpleasant consequences. D) Thanks to the subtle, deep and, most importantly, harmless comments of the scientific supervisor, all eleventh graders completed their work with the abstract. D) In ​​the painting “Moscow Courtyard” by V.D. Polenov depicted a small corner of old Moscow. GRAMMAR ERRORS 1) misuse case form of a noun with a preposition 2) a violation of the connection between the subject and the predicate 3) a violation in the construction of a sentence with an inconsistent application 4) an error in the construction of a sentence with homogeneous members 5) an incorrect construction of a sentence with a participle phrase 6) a violation in the construction of a sentence with a participial phrase 7) incorrect construction of a sentence with indirect speech 8. Identify the word in which the unstressed vowel of the root being tested is missing. Write out this word by inserting the missing letter. Prik...dream business...kates gr...risty vile...live choose 9. Identify the row in which the same letter is missing in both words in the prefix. Write out these words by inserting the missing letter. o...throw, on...cut pr..lip, pr..good ra...straighten, and...move pr...grandmother, come...come pr...tear, pr...measure 10. Write down a word in which the letter E is written in the place where there is a gap. Eavesdrop on a picky... loving... twisted... 11. Write down a word in which the letter I is written in a place where there is a gap. .shya distributing...my key...howl...rigged 12. Find a sentence in which NOT is spelled CONTINUOUSLY with the word. Open the brackets and write down this word. After the compere’s statement, applause was (not) immediately heard in the auditorium: the audience was thinking about what the artist had said. (Not) seeing the quarrelsome little dog at first, the horse spread its front legs wide apart, bowed its head and froze in surprise. The road to the brave travelers was now blocked by a (not) deep, but quite wide river. There are still many interesting and necessary books for every person to read. Spectators watched the bright spectacle with bated breath, and the (non)stopping stream of delegations from different countries everything stretched across the sports arena. 13. Find a sentence in which both highlighted words are spelled CONTINUOUSLY. Open the brackets and write down these two words. The need for creativity is JUST as natural as the need to quench thirst or hunger, (THUS) every person, in one way or another, tries to realize his creative potential. A.I. Kuprin was sure that WHEN, in terribly distant centuries, the ancestor of modern man flew not only in a dream, but also (IN) REALITY. We need to live in such a way that in every person we come into contact with in life, SOMETHING good remains from us, from the work of our souls. We come into the world in order to comprehend beauty, and ALSO to create and approve it. Before each performance, until the audience appeared in the hall, the leading actor usually walked slowly across the stage and (WHILE) muttering SOMETHING under his breath. 14. Indicate all the numbers in whose place NN is written. Our dog, the big shaggy Polkan, stood aside in confusion (1) as if puzzled (2) by his own (3) generosity, when the older wild goat, blocking the younger one, ran past her, almost touching her side with her shaggy mat (4) wool 15. Place punctuation marks. Indicate the numbers of sentences in which you need to put ONE comma. 1) It is impossible not to admire the reflection of the sun in myriads of drops of morning dew and shiny threads of rain on a sunny day. 2) In the paintings of this wonderful landscape painter there are no mighty mountains, no cypress trees, no lush southern flowers, no azure sea. 3) During the flight, a feeling of violent and tremulous delight engulfed my soul with some kind of cold and sweet flame. 4) Around us, the ice floes collided and became vertical, climbed on top of each other and broke with a loud crash. 5) The measure of intelligence is not only beliefs and morals, but also actions. 16. Place punctuation marks: indicate all the numbers that should be replaced by commas in the sentence. Drops of blind rain (2) falling from the sky (3) sparkling in the sun (1) look like precious stones (4) shimmering with all their facets. 17. Place punctuation marks: indicate all the numbers that should be replaced by commas in sentences. One of the most interesting toys (1), according to many guys (2), is a magnet, with which everyone (3) can (4) conduct various experiments. 18. Place punctuation marks: indicate all the numbers that should be replaced by commas in the sentence. A deep winding river (1) from the dark waters (2) of which (3) the most successful fishermen pulled out dozens of large bream (4) flowed immediately beyond the village. 19. Place punctuation marks: indicate all the numbers that should be replaced by commas in the sentence. The hostess had already looked out the window many times (1) to quickly see the long-awaited guests (2) and (3) when the sound of an approaching car was heard in the distance (4) she ran out onto the porch. Read the text and complete tasks 20-25. (1) The treasures given to us by Pushkin are truly great. (2) The first merit of the great poet is that through him everything that can become smarter becomes smarter. (3) In addition to pleasure, in addition to forms for expressing thoughts and feelings, the poet also gives the very formulas for thoughts and feelings. (4) The rich results of the most perfect mental laboratory are made common property. (5) The highest creative nature attracts and aligns everyone with itself. (6) The poet leads the reader to a country unfamiliar to him, in the subtle and fragrant atmosphere of which the soul is elevated, thoughts are improved, and feelings are refined. (7) Why is each new work of the great poet so eagerly awaited? (8) Because everyone wants to think sublimely and feel with him; everyone is waiting for him to tell me something beautiful, something new, something I don’t have, something I lack; but he will say, and it will immediately become mine. (9) That’s why there is love and admiration for the great poet, that’s why great tribulation upon its loss. (10) Without it, emptiness, mental orphanhood is formed: there is no one to think with, no one to feel with. (11) It is easy to feel pleasure and delight from an elegant work, but it is quite difficult to notice and trace your mental enrichment from the same work. (12) Everyone says that he likes this or that work, but rarely does he realize and admit that he has become wiser from this work. (13) Many people believe that poets and artists do not give anything new, that everything they created was somewhere before, with someone, but remained hidden because it could not find expression. (14) This is not true. (15) The error occurs because all great scientific, artistic and moral truths are very simple and easily digestible. (16) But no matter how simple they are, they are still proposed only by creative minds, and are only assimilated by ordinary minds, and then not suddenly and not in all their fullness, but according to the strength of each. (17) People admired Pushkin and grew wiser, they admire him and become wiser. (18) Our literature owes its mental growth to him. (19) And this growth was so great, so fast that the historical sequence in the development of literature and public taste was as if destroyed and the connection with the past was severed. (20) Russian literature in one person has grown for a whole century. (21) Pushkin found Russian literature in the period of its youth, when it still lived by foreign models and, based on them, developed forms devoid of living, real content - so what? (22) He himself left samples equal to those of mature literature, samples perfect in form and in original, purely folk content. (23) Before Pushkin, our literature was imitative; along with its forms, it took from Europe various historical trends that had developed there, which had no roots in our life. (24) The writers’ attitude to reality was not direct, sincere; writers had to choose some conventional point of view. (25) Freeing thought from the yoke of conventional techniques is not an easy task; it requires enormous strength. (26) A solid beginning for the liberation of our thoughts was laid by Pushkin: he was the first to approach the themes of his works directly, directly, he wanted to be original and became so - he became himself. (27) Every great writer leaves behind a school, leaves followers, and Pushkin left a school and followers. (28) What kind of school is this that he gave to his followers? (29) He bequeathed to them sincerity, originality, he bequeathed to everyone to be themselves, he gave courage to all originality, he gave the courage to a Russian writer to be Russian. (30) It’s just easy to say! (31) After all, this means that he, Pushkin, revealed the Russian soul. (32) Now we can only wish that Russia would produce more talent, to wish the Russian mind more development and space; and the path along which talents should go was indicated by our great poet. (According to A.N. Ostrovsky) Alexander Nikolaevich Ostrovsky (1823-1886) is a Russian playwright, whose work became the most important stage in the development of the Russian national theater. 20. Which of the statements correspond to the content of the text? Please provide answer numbers. 1) Outstanding poets actually only express what previously existed in someone’s mind, but could not find expression. 2) A brilliant poet is able to convey to readers not only a form for expressing thoughts and feelings, but also the thoughts and feelings themselves. 3) Great truths are simple. 4) Creativity of A.S. Pushkin marked the beginning of the originality of Russian literature. 5) A.S. Pushkin wrote the poem “The Bronze Horseman”. Which of the following statements are true? Please provide answer numbers. Sentences 1-5 present the reasoning. Sentences 7-8 contain the narrative. Proposition 14 provides an assessment of the reliability of the content of the statement made in sentence 13. 4) Sentences 15-16 provide a description. 5) Sentence 29 contains the answer to the question posed in sentence 28. 21. 1) 2) 3) From sentence 11, write down the antonyms (antonymous pair). Among sentences 15-20, find one that is related to the previous one using a personal pronoun and cognates. Write the number of this offer. 24. “Discussing the greatness of the creative heritage of A.S. Pushkin, the author uses a trope such as (A) ________ (in sentences 4, 6, 20). A.N. Ostrovsky conveys his idea of ​​​​the impact of the works of a brilliant poet on readers, of their perception of great truths, using the technique - (B) ___ (“no one with” in sentence 10, “to admire and grow wiser” in sentence 17), and also a syntactic device - (B) _____ (in sentence 15). Involving readers in thinking, the author uses the technique - (D)_______ (sentences 7-8, 28-29).” 22. 23. List of terms: 1) parcellation, 2) metaphor, 3) antonyms, 5) series homogeneous members sentences, 6) lexical repetition, 8) phraseology, 9) question-answer form of presentation 4) litotes, 7) synonyms, Option 14 (USE-2015) 1. 2. 3. 4. 5. 6. 7. 8. 9 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. Option 14 45<или>54 in the future<или>in the future 3 more beautiful difficult<или>difficult lie down 76213 mountainous straighten outcome<или>outcome straighten key linger shallow<или>shallow to also<или>also to 1234<или>any other sequence of these numbers 45<или> 54 234 <или>any other sequence of these numbers 12<или> 21 14 <или> 41 1234 <или>any other sequence of these numbers 234<или>any other sequence of these numbers 135<или>any other sequence of these numbers is easy difficult<или>difficult easy 18 2659 Approximate range of problems Author's position 1. The problem of the influence of creativity of A.S. Pushkin on the reader’s personality. (What influence does the work of A.S. Pushkin have on the reader’s personality?) 1. The work of A.S. Pushkin enriches the mind and soul of readers, the poet makes his thoughts and subtle sublime feelings public property, raising the reader to his level - the level of the highest creative nature. 2. The problem of people's need for the best works. (Why do people need the works of their beloved poet?) 2. People feed their soul and mind with the work of their beloved poet, feeling the need to think and feel with him, therefore, when they lose the creator, they experience a feeling of mental orphanhood. 3. The problem of the peculiarities of perception of the works of poets and artists. (Why is it difficult for a person to realize his mental enrichment when perceiving a work of art?) 3. Since the great scientific, artistic and moral truths are very simple and easily assimilated, it seems to people that poets and artists do not create anything new, only expressing what has already existed for a long time. But these truths are created by great minds, and only assimilated by ordinary ones, and not always in their entirety. 4. The problem of the influence of creativity of A.S. Pushkin on the formation of Russian literature. (What is the significance of A.S. Pushkin’s work for Russian literature?) 4. Russian literature grew in the work of A.S. Pushkin for a whole century, she owes the poet mental growth, living, real, original, purely folk content and perfect forms. 5. The problem of the creative will of A.S. Pushkin. (What is the creative testament of A.S. Pushkin?) 5. A.S. Pushkin bequeathed to his followers sincerity, originality, the ability to be oneself, to show originality, gave the Russian writer the courage to be Russian - revealed the Russian soul.

The various applications of superconductivity began to be discussed almost immediately after the discovery of this amazing phenomenon. Even Kamerling-Onnes believed that with the help of superconductors it was possible to create economical installations for producing strong magnetic fields. However, the real use of superconductivity began only in the late 50s and early 60s. Currently, superconducting magnets of various sizes and shapes are already in operation. Their use has gone beyond the scope of purely scientific research, and today they are widely used in laboratory practice, in accelerator technology, tomographs, and installations for controlled thermonuclear reactions. With the help of superconductivity, it has become possible to increase the sensitivity of some measuring instruments. Particular attention should be paid to the influence of SQUIDs in technology, including modern medicine. Superconductivity has become a large industry in its own right. The discovery of high-temperature superconductivity created the prerequisites for the wider introduction of various superconducting devices into everyday practice.

Superconductors are currently most widely used in the field of creating strong magnetic fields. Modern industry produces a variety of wires and cables from type II superconductors, used for the manufacture of magnet windings. The advantages of superconducting magnets are obvious. With the help of superconductors, significantly stronger magnetic fields are obtained than when using iron magnets. Superconducting magnets are also more economical.

It should be noted that the maximum possible magnetic field produced by superconducting magnets is limited by an upper limit on the current density (critical currents). The critical current is determined, as a rule, by the conductor preparation technology, and not by the upper critical field of the material.

Superconducting magnets have another advantage over conventional ones. They can operate in short-circuited mode, where the field is frozen in the volume, which provides virtually time-independent field stability. This property is extremely important when measuring nuclear magnetic and electron paramagnetic resonances in matter, in tomographs, etc.

In superconducting solenoids with a large field volume, the stored energy is quite large. If the coil returns to its normal state, this energy will turn into heat. If, during the transition to a normal state, all the energy uncontrollably turns into heat, this can lead to complete destruction of the magnet. To avoid such catastrophic consequences of the spontaneous transition of the coil to its normal state, solenoids, especially large ones, are equipped with special protective devices designed to quickly release stored energy.

It is very tempting to try to use superconductors in electrical engineering and energy. Indeed, at present, losses due to Joule heat in conducting wires are estimated at 30 - 40, that is, more than a third of all produced energy is wasted in vain - on “heating” the Universe. If you transmit electricity through superconducting wires with zero resistance, then there will be no such losses at all. This is equivalent to an increase in electricity generation by more than a third. Superconductors can be used to create electric motors and generators with high efficiency and other improved performance characteristics.

If a superconducting sphere is placed above a metal ring with current, then a superconducting current is induced on its surface due to the Meissner effect, which leads to the appearance of repulsive forces between the ring and the sphere, and the sphere hangs above the ring. A similar mechanical repulsion effect is observed when a permanent magnet is placed above the superconducting ring. This effect, often used to demonstrate the phenomenon of superconductivity, was called the “coffin of Mohammed”, because, according to legend, the coffin of Mohammed hung in space without any support.

The phenomenon of mechanical repulsion is used, in particular, to create bearings and supports without friction. The prospect of using superconductor levitation in transport is tempting. We are talking about creating a magnetic levitation train in which there will be completely no friction losses on the road track. A model of such a 400m long superconducting road was created in Japan back in the 70s. Calculations show that a magnetic levitation train will be able to reach speeds of up to 500 km/h. such a train will “hover” above the rails at a distance of 2 - 3 cm, which will give it the opportunity to accelerate to the specified speeds.

Superconducting cavity resonators are currently widely used. On the one hand, such superconducting resonators make it possible to obtain high frequency selectivity. On the other hand, superconducting resonators are widely used in superconducting accelerators, allowing a significant reduction in the power required to create an accelerating electric field. As a rule, superconducting resonators are made of lead or niobium.

One of the most common areas of applied superconductivity is the use of SQUIDs, both in scientific research, and in various technical fields. SQUID-based gradiometers respond to extremely weak magnetic fields, which is why they are already effectively used today in medicine and biology to study the fields of living organisms and humans. In geology, SQUIDS are used to determine changes in the force of gravity at various points on the Earth. Such information is needed to search for minerals.

Cryoenergetics and cryoelectronics are considered the most promising areas for the widespread use of high-temperature superconductors. In cryoenergetics, a technique has already been developed for the preparation of fairly long wires (up to 1000 meters), wires and cables based on bismuth HTSC materials. This is already enough for the manufacture of small motors with superconducting windings, superconducting transformers, inductors, etc. Based on these materials, superconducting solenoids have already been created, providing magnetic fields of the order of 10,000 Gauss at the temperature of liquid nitrogen (77 K).

The pace of technological and applied research is very high, so it is possible that industry will master the production of products from high-temperature superconductors before the nature of superconductivity in metal-oxide compounds is reliably clarified. What is primarily important for technology is the very fact of the existence of materials that are superconducting at the temperature of liquid nitrogen. However, purposeful and meaningful movement forward, including in the technological sphere, is impossible without a comprehensive study of already known HTSCs, without understanding all the intricacies of high-temperature superconductivity as the most interesting physical phenomenon. This is especially true for the search for new superconductors.

I gave just a few examples practical use superconductivity. Of no less importance, of course, are the problems of transmitting electricity over long distances without losses, creating energy storage devices, protecting spacecraft from cosmic radiation, etc. There are many examples of scientific and technical applications of superconductivity, but such a study of these issues is beyond the scope of this work.