It became clear to scientists that nuclear transformations can become a source of enormous energy just a few years after the discovery of A. Becquerel and P. Curie. Thus, in 1910, V.I. Vernadsky, in a report at the general meeting of the Academy of Sciences, said that humanity, having learned in the future to control the processes of atomic decay, would receive into its hands such a powerful source of energy that it had never known before. But in 1922, he also warned that the time to master atomic energy was close, and the main question was how humanity would use this colossal source of energy - to increase its well-being or for self-destruction. The subsequent creation of nuclear weapons of mass destruction and accidents at industrial nuclear power facilities, primarily at nuclear power plants (NPPs), show the relevance of the scientist’s warning.

CHERNOBYL TRAGEDY
CHRONICLE OF EVENTS and ECOLOGICAL CONSEQUENCES

From the standpoint of the country's environmental safety, radioactive contamination is one of the most important threats. And the share of nuclear power plants in this threat is very significant. We may be exaggerating this threat, but only Chernobyl alone fully justifies this threat of ours.

Corresponding Member of the RAS A.V. Yablokov

The explosion of the fourth power unit of the Chernobyl Nuclear Power Plant (ChNPP) occurred on April 26, 1986 at 01:23:40 and caused primarily the mechanical destruction of many fuel cassettes - nuclear fuel (fuel elements - fuel rods) - and the explosive release of a significant amount of dispersed nuclear fuel, containing more than 100 different radionuclides.

The first stage of the accident - two explosions: after the first - within 1 s, the radioactivity of the reactor increased 100 times; after the second - after 3 s, the radioactivity of the reactor increased 440 times. The mechanical power of the explosion was such that the upper protective plate of the nuclear reactor of a block weighing 2 thousand tons shattered, exposing the reactor.

The second stage of the accident (April 26 – May 2) is the burning of graphite rods due to the release of enormous energy.

During the burning of the rods, the temperature inside the reactor did not drop below 1500 °C, and after May 2 it began to rise, approaching 3000 °C, which caused the melting of the remaining nuclear fuel (zirconium, from which fuel rod assemblies are made in all types of reactors, has a melting point of 1852 °C).

The burning of the reactor, although with less intensity, continued until May 10. From the burning reactor, as if from the crater of a volcano, burning particles of the destroyed reactor and radionuclides with radioactivity amounting to millions of curies were thrown out.

Domestic atomic experts have identified the main technical cause of the accident. The explosion of the reactor of the fourth block of the Chernobyl Nuclear Power Plant was the result of an engineering design defect in the very technical design of water-graphite reactors of the RBMK series (high-power boiling water reactor) - reactors modernized for nuclear energy, which worked for more than 40 years at the Mayak production association, producing weapons-grade plutonium. Without going into the design features of RBMKs, we note that they are not able to stop the uncontrolled “acceleration of reactivity” if an emergency stop is necessary when operating at extreme power.

Another cause of the accident was the human factor - criminal neglect of work and safety rules and unprofessionalism of some of the personnel.

The load of the RBMK-1000 reactor installed at the Chernobyl nuclear power plant unit is 100 tons with an enrichment of 1.8% (1800 kg of uranium-235). Experts found that 3.5% of the fission products in the reactor (63 kg) were released into the atmosphere. For comparison: as a result of the explosion atomic bomb dropped on Hiroshima, only 0.74 kg of radioactive waste was generated.

The official estimate of the radioactivity of nuclides released from the Chernobyl reactor (50 million Ci) is clearly underestimated, since it was obtained after recalculating radioactivity on May 6 and did not take into account most of the short-lived radionuclides (including iodine-131, its half-life is 8.1 days ), which are extremely dangerous, and their release until May 6 accounted for more than 80% of the radioactivity in the air and on the surface of the Earth. During the heating period of the reactor from May 2 to May 6, the release of radioactive iodine increased, and at the same time the release of other radionuclides, especially cesium-134 and -137, strontium-89 and -90, radionuclides of barium, ruthenium, cerium, etc., increased significantly.

According to American experts, the activity of radioiodine at the time of the explosion was 100 million Ci (“typical” nuclear explosions in the atmosphere carried out before 1968 produced up to 159 thousand Ci).

At the moment of the explosion, a huge, 2 km high, cloud of radioactivity of tens of millions of curies was formed, consisting of aerosols - dispersed hot particles of nuclear fuel mixed with radioactive gases.

After the explosion, large fragments of fuel cassettes and graphite appeared on the territory of the fourth block, which liquidators of the accident collected with bulldozers and shovels (!). Until May 2, they tried to prevent the burning of graphite in the destroyed reactor by dropping bags of sand, dolomite and other substances from helicopters (about 5,000 tons were dropped), while the helicopters had to fly at an altitude of 150 m directly above the mouth of the reactor.

Small pieces of nuclear fuel fused with asphalt were scattered throughout the station, and it was impossible to collect them. As a result, to protect against radiation, the entire territory of the station was covered with a layer of concrete and asphalt 1.5 m thick.

Fortunately, in the western and northwestern direction, where the first most concentrated cloud of hot radioactive particles and radioactive gases began to spread, there were no cities or densely populated areas. A change in wind direction by 180° a week later, when the highly radioactive gas-aerosol stream was still flowing from the reactor core, led to a wide dispersion of radioactive products.

Along the axis of movement of the explosive radioactive cloud, just a few days after the explosion, a five-kilometer strip of dying forest began to appear, called the “red forest”, because the needles of the pine trees changed their color from green to yellow-red. A strip of dead forest, where tree crowns received doses of 10,000–11,700 rad (radiation adsorbed dose - one of the off-system units of absorbed radiation dose, 1 rad = 0.01 Gy; in the SI system - gray (Gy): per 1 kg of substance When a radiation dose of 1 Gy is absorbed, 1 J of energy is released), which is an order of magnitude higher than lethal doses for vegetation, and occupied an area of ​​38 km 2 . All small mammals died in this forest.

With precipitation and in the form of dry fallout along the “Chernobyl trace,” contamination of water bodies and soil occurred. After short-lived radioactive isotopes disappeared from the environment, the main danger became radioactive dust from dry particles of nuclear fuel, since it could easily be lifted by the wind and enter the lungs. Even five years later, up to 25,000 such particles per 1 kg of lung tissue were found in wild mammals - elk, wild boar and others - that lived in the exclusion zone.

According to official data, the total area contaminated with radionuclides with an indicator of 0.2 mR/h (background permissible value of 0.01 mR/h) in the first days after the accident amounted to 200 thousand km 2, and the area of ​​​​the zone with a contamination level of 15 Ki/km 2 for cesium-137 (100 times higher than the national average) - 10 thousand km 2. Almost a quarter of a million people lived on the territory of the latter.

After the accident, it was decided to establish an exclusion zone, where the radiation power was 0.2 mSv/h (sievert (Sv) - a unit of equivalent radiation dose in the SI system, the main dosimetric unit in the field of radiation safety, introduced to assess the possible damage to human health from chronic exposure to radiation; 1 Sv = 1 Gy), and resettlement zones where the radiation power was 0.05 mSv/h (according to the recommendations of the International Atomic Energy Agency (IAEA), areas where radiation doses exceed 5 mSv per hour should be considered a mandatory resettlement zone year!). The city of power engineers, Pripyat, was mothballed and depopulated. True, after some time, the Government Commission for the Implementation of Population Protection decided not to carry out forced evacuation of people from the mandatory resettlement zone in order to avoid stress and socio-psychological tension (!).

Only years after the disaster, some information appears in the press about those changes in living organisms at the genetic level that occurred as a result of irradiation during and after Chernobyl accident. Monitoring of the state of the natural environment in the zone affected by the consequences of the Chernobyl accident has been constantly carried out by the State Committee since its formation. Russian Federation on protection environment(1996–2000).

In the first days of the tragedy, no special medical measures were taken to protect the population from radiation damage. Iodine prophylaxis (taking potassium iodide tablets with food to saturate the body with stable iodine and prevent the absorption of radioiodine) began even in Kyiv only after May 10, i.e. too late. In rural areas, iodine prophylaxis began even later, and often was not carried out at all.

Since from the end of April radioiodine entered the body mainly through food, at the beginning of May in Kyiv the population was supplied with powdered milk from state reserves. In rural areas, the supply of clean food to the population was organized very late and not everywhere. Residents of villages within a 30-kilometer zone continued to consume contaminated products until the evacuation, i.e., for 9–10 days. Outside this zone, control of radioiodine content was established only for milk sent to dairies. In private households, children continued to consume foods contaminated with radioiodine for weeks.

Subsequently, much better control was established over the content of radiocesium, but this isotope, although long-lived, is considered less dangerous and non-carcinogenic, since it accumulates in the muscles and is quite easily excreted from the body. At the same time, control over strontium-90 is poorly organized to this day, because it requires complex equipment. Meanwhile, strontium-90 is 40–50 times more radiotoxic and carcinogenic than radiocesium.

Functional and morphological changes in the thyroid gland were most quickly discovered by radioecologists in wild ungulates (elk, deer), as well as by veterinarians in cows, goats and other farm animals that absorbed huge amounts of radioactive iodine with plants. Absorbed doses by the thyroid gland in cows in areas surrounding Chernobyl sometimes ranged from 2500 to 2800 rads. Cases of destruction and atrophy of the thyroid gland and death of animals were often observed.

Radiation doses to the thyroid gland in children in the area of ​​the accident on a mass scale were 250–1000 rad. It turned out that domestic doctors were not aware that iodine prophylaxis and a ban on milk consumption are two fairly simple and accessible methods that could easily prevent radioiodine overexposure. Immediately after the Chernobyl accident, these methods were widely used in Poland, Sweden, Austria, and Southern Germany, which were affected by the wing of the Chernobyl cloud.

According to the World Health Organization (WHO), the number of diseases of the thyroid gland, which selectively accumulates radioactive iodine, in children should increase over time, reaching a peak (40% increase) after 13-15 years, i.e. currently. From a secret note from the USSR Ministry of Health dated November 11, 1986, sent to the Politburo and declassified in 1992, it became known that 1 million 694 thousand children were exposed to iodine irradiation. The incidence of thyroid cancer in children has been increasing in Ukraine since 1990.

The consequences of the Chernobyl disaster are still evident today. The area of ​​radioactively contaminated agricultural land currently amounts to 3.5 million hectares. In 1999, the highest density of contamination with cesium-137 and, accordingly, higher concentrations of this radionuclide in food products were registered in the Bryansk region. Here, as well as in some areas of the Kaluga, Oryol and Tula regions, the radiation situation remains unfavorable: more than 2 million hectares of agricultural land have a cesium-137 contamination density of more than 1 Ki/km 2, including more than 300 thousand hectares - over 5 Ci/km 2 (with the average background value for Russia being 0.15 Ci/km 2).

Radiation contamination as a result of the Chernobyl accident is still observed in densely populated areas where forests are of important economic and social importance (mainly the Bryansk region). The area of ​​forest land contaminated with cesium-137 as a result of the Chernobyl accident is 1 million hectares. At the same time, it is not possible to completely stop the use of forest resources and forestry activities in zones of radioactive contamination; At the same time, forestry management here without special protective measures leads to an increase in radiation doses to the population.

Currently, the radiation situation in forests has stabilized and a recovery stage has begun, which, given the current composition of radionuclides, will last for tens, and in some cases, hundreds of years. At this stage, the root intake of radionuclides predominates compared to the external one, the coefficient of transfer of radionuclides from soil to plants increases in the series: coniferous trees - deciduous trees - young trees (the highest content of radionuclides was noted in vegetative organs - needles, leaves, shoots - compared to wood ) – wild berries – mushrooms. On wet and waterlogged soils, this process is much more intense.

Measures to protect the population and rehabilitation work in contaminated areas due to the disaster at the Chernobyl nuclear power plant, constant radiation monitoring of agricultural products (milk, meat, hay, green mass, mushrooms), providing residents of the most affected areas with food products with therapeutic and prophylactic properties in accordance with special Decree of the Government of the Russian Federation dated December 18, 1997, unfortunately, are not implemented in full due to insufficient funding (for some items only by 40%). As a result, in 1999, liming of soils on land with a pollution density of more than 5 Ci/km 2 was carried out by 65.8%, and radical improvement of meadows and pastures was carried out by only 32.9%.

Summing up the sad outcome of the Chernobyl disaster that occurred in 1986, we note that 80 thousand people died, more than 3 million people were injured, of which 1 million were children. Chernobyl brought losses comparable to the state budgets of entire states, and the consequences of this disaster will not be overcome in the foreseeable future. The shutdown of the last operating power unit of the Chernobyl nuclear power plant in December 2000 does not fully solve environmental problems this station. Work to dismantle the station is not only designed to take decades, but also does not have a reliable scientific and technical basis and, in addition, is very expensive. The Chernobyl nuclear power plant is overflowing with spent fuel; the money that the West promised for closing the station ($1.5 billion) is barely enough to transport this fuel to reprocessing plants and disposal - one special train for transporting radioactive waste costs at least a billion dollars. In 10 years, and perhaps much earlier, it will be necessary to build a new sarcophagus for the fourth power unit of the Chernobyl nuclear power plant, which will require high-quality cement and special metal for fittings, which neither Ukraine nor Russia has.

In the time since the Chernobyl disaster, the situation with the safety of nuclear facilities, especially nuclear power plants and especially in our country, has only worsened. Emergency situations at nuclear power plants have almost become the norm of their work. Moreover, in 1999, at the Kola Nuclear Power Plant, one of the power units was shut down due to the fact that someone freely penetrated the station control unit and tore out electronic boards containing precious metals from the cells, as a result of which the oil pressure sensors in turbine unit of the power plant, which could have led to a serious disaster if the emergency protection system had not worked. The saddest thing is that the attacker was not detained at the crime scene, but only a few days later, when he tried to sell the stolen circuit boards.

The potential environmental hazard of the Chernobyl nuclear power plant and other nuclear energy facilities, according to many respected environmental scientists, still remains extremely high.

E.E. Borovsky

The bitter lesson of Chernobyl is not only in the disaster itself, but also in the fact that fear of the truth increases the consequences of disasters many times over. However, not everyone still wants to understand this...

My guest - Chernobyl

The doorbell rang. I'm through the peephole
looked and froze - under the fox earflaps
not that there was no face at all,
like in a book about an invisible maniac,
but it was woven by someone
from black billowing smoke
and moved, becoming easily
completely different faces, but only
the eyes did not change in this smoke,
like the same smoke condensed into balls.
I pretended I wasn't there
closed his eye, breathing completely inaudibly,
and tiptoed away from the door.
But through the keyhole, snaking,
smoke began to creep in and became a figure
in a coat, put on with pot-bellied smoke,
and in a black hat over a face of smoke
and with fingers made of smoke, but nevertheless
with an undeniably engagement ring,
which confirmed that this smoke was married.
I muttered, coughing: “Who are you?”
The alien raised his hat: “I am Chernobyl.”
“Excuse me, but you are not a person.
You are atomic disintegration, you are a catastrophe,”
Involuntarily shuddering, I muttered.
Chernobyl said with a feeling of superiority:
"All disasters are hidden inside
us all. They are symbolized by people
and Poincaré's nickname - War
back during the First World War
No wonder they gave it to the fat man, a Frenchman.
Who, say, is the Holocaust? Of course, Hitler...
Who is Stalin? The Gulag Archipelago..."
“Who are you, Chernobyl? Whose face
coming towards you? “No, not Gorbachev,
although that explosion happened with him,
and it was his fault for the silence...
My face is not a face, but a facelessness.
Remember how it was then
how the authorities cowardly lied to the people of Kiev,
hiding the disaster like a secret,
and at the same time swallowing disaster,
and walked like children with red flags,
fellow citizens poisoned by me.
And again you recently visited Chernobyl,
when the submarine was suffocating at the bottom,
and the authorities were confused in explanations,
and the lie became a vulgar requiem.
Who am I, Chernobyl? Animal fear of truth.
As long as he is immortal, I am immortal.”
“But they’re closing you,” I exclaimed. –
Wouldn't a sarcophagus help?
“Did he make Stalin weaker? –
Chernobyl grinned at me. –
You didn’t guess why I came to you
fell into the cracks as an unwanted guest?
You - heard - blurted out something about the anthem
according to Stalin's old recipe.
In vain, my dear, you said
about an old anthem full of nostalgia,
that you won’t get up in front of him...
Imagine everyone is standing up, and you are sitting...
They will immediately shout at you “Anti-patriot!”
To all you outdated democrats,
The Soviet atom advises to stand up..."
And either a man or a beast,
my unexpected midnight guest has disappeared,
and for a long time I, staring at the door,
I was waiting for black smoke from the keyhole...

Almost 30 years ago, the world's attention was drawn to a Ukrainian city where a nuclear power plant exploded, becoming the world's worst nuclear disaster.
The world has come a long way since that horrific event in 1986, but one thing that hasn't changed much in polluted Chernobyl is the dead trees and leaves. They don't decompose nearly as fast as flora in other places in the world.

“We were stepping over all these dead trees on the ground that had been knocked down by the first explosion,” said Tim Musso, a biology professor at the University of South Carolina. – Years later, these trunks are perfectly preserved. If a tree fell in my garden, within 10 years it would turn into dust.
Tim Mousseau and his colleague Anders Muller from the University of Paris-Sud conducted long-term studies of the biology of radioactive regions such as Chernobyl and Fukushima, Japan.
Much of their work took place in the Red Forest, the notoriously forested region around Chernobyl where trees turned an ominous reddish-brown before dying. The scientists noted that the tree trunks appear to have remained largely unchanged, even after two and a half decades have passed.
“With a few exceptions, almost all of the dead tree trunks were intact when we first encountered them,” says Tim Musso, who also heads the Chernobyl and Fukushima Research Center.
To find out what happened, or rather, what did NOT happen, the researchers collected hundreds of samples that had not been exposed to radiation and packed them into insect-proof bags. They then distributed them throughout the Chernobyl area and left them there for nine months.
The results were striking: samples of fallen leaves left in areas with high levels of pollution showed decomposition rates 40 percent lower than leaves left in uncontaminated areas. At all sites, the degree of decomposition was proportional to the level of radioactive contamination.
Radiation is known to negatively affect microorganisms such as bacteria and fungi. A recent study demonstrated that radiation therapy can cause serious complications by reducing populations of beneficial bacteria in the gut.

Musso and other experts are concerned that the accumulation of fallen leaves on the ground in the forest is a real danger. “We have increasing suspicions that a catastrophic fire will occur in the coming years,” the scientist notes.
In the event of a forest fire, the leaves that have not decomposed for 28 years will become an ideal fuel, and the fire will spread radiation throughout the region. “As a result, radiocesium and other pollutants will enter the settlements", emphasizes Musso.
“Fallen leaves, which have accumulated, apparently due to reduced microbial activity, are excellent material for kindling,” the scientist added. – They are dry, light and burn well. This once again proves that it can begin

Our correspondent visited Pripyat and tried to refresh in his and your memory some facts about radiation, which had become very dim after graduation. He brought the article, but did not become the Hulk: he returned as skinny and white as he left. And that's what we hoped...

Radiation Theater

There are several interesting objects in the Zone: the station itself, the abandoned city of Pripyat and the Russian Woodpecker installation.

The same 4th power unit of the Chernobyl nuclear power plant looks everyday today. Background outside - 5–9 microsieverts per hour (2-3 times higher than in an airplane)

In total, more than 600 thousand people took part in the liquidation. Having arrived and having collected an acceptable, and sometimes unacceptable, dose, the person left for retirement. The remaining reactors operated for another decade and a half. A new roof was placed on the 4th block, the station was washed many times until it was shiny, filled with concrete, the scattered pieces of fuel were collected and taken away, and the layer of soil around was cut off. The work continues to this day and will continue for at least another fifty years.

The tour can even be taken under the sarcophagus into the ominous block number 4 - not into the reactor hall itself, but to the control panel where the events unfolded. It's dark and desolate here. Background - 2-13 microsieverts per hour (one minute here is like 1-6 minutes on an airplane, you can live). But the particle pollution is severe: several hundred particles per minute per square centimeter. You cannot breathe without a respirator; you need special, replaceable clothing.

At the exit - mandatory control of hands, feet and clothing. And this is not the last frame on the way. Radioactive dust is just dust. It is recommended that you first wash your hands with cool water and soap. Nuclear workers always wash with cold water, since warm water expands the pores and dust can become lodged in the skin for a long time. They also say that nuclear workers wash their hands twice in the toilet - before and after. And it's not a joke.

The station is full of life, thousands of people work here from different countries: waste processing and disposal plants are being launched (where to build them if not here?), a giant arch is being built, which in a couple of years will be rolled onto the reactor so that it can be dismantled. Final goal- the concept of a “green lawn”: dismantle all the uncontrollably stinking horror inside, carefully recycle and bury.

Where to find radiation if you are an alien and cannot live without it

Any granite is noticeably phonite. Granite embankments, tiled metro stations, slabs in a building materials store - everywhere you can see a heightened background.

Rhodonite is a good phonite - a stone resembling red granite. In Moscow, for example, they decorated the Mayakovskaya metro station.

Chernobyl plant area, Fukushima, former test sites nuclear tests.

Household devices. Isotopes are used in fire detectors. The simplest isotope of hydrogen, tritium, which emits beta particles with a half-life of 12 years, can be completely legally purchased in the form of a luminous keychain with the straightforward name Betalight.

In Moscow, the ravines of the Kolomenskoye Park on the slope of the river, where waste was previously buried, are blazing. There are nuclear burial sites near Sergiev Posad and Podolsk. And in Moscow there are many institutes with such dirt inside, left over from experiments of past years, that it is scary to enter them.

On this page we have placed a small sample containing the radiation isotope-404. Try not to touch it with your hands or lick it until you get a home dosimeter.

Pripyat city

Today, in terms of radiation, Pripyat is thousands, hundreds of thousands of times cleaner than in the days after the accident. There are excursions into the city: here you can walk and breathe without respirators. The biggest danger is falling buildings. It is not recommended to touch objects with your hands, sit on the ground, drink or eat: dust may get in. The city will never come back to life. Children will never be able to play in the sandbox here. Grandmothers will not grow radishes in their garden beds. Water for drinking and, probably, even for showering will have to be transported from cleaner places. But this is a unique reserve of the era. Perhaps this is the only place on the whole Earth where you can see a piece of the real Soviet Union 80s of the last century.

Preserved frescoes on the walls of collapsing buildings

Monument to firefighters who worked at the Chernobyl nuclear power plant

The dirtiest place in the city is the basement of the city hospital: jackets, helmets and boots are dumped here, which the firefighters of that fatal brigade took off when they returned from extinguishing the roof of the block. Everything is covered with soot and nuclear fuel particles. Even after almost 30 years, clothing transmits up to one x-ray per hour - it is impossible to enter the basement without special suits and respiratory protection. Almost all the firefighters died within a month; they were buried in lead coffins: the bodies were dangerously flammable. Other dirty places in Pripyat are sewers and drains. Rains have washed away radioactive dust here for decades.

Test in North Korea that caused a 4.9 earthquake

In addition to accidents, there are a couple of thousand nuclear tests all over the world: underground, on land, underwater, in the atmosphere. There are more than nine hundred in Nevada alone. An emergency involving the loss of radioactive parts (for example, in 1987 in Goiania, Brazil, when cretins stole a luminous isotope and rubbed the whole village with it). And also constant emissions from the drying up radioactive reservoir at Mayak in 1960-1985. But even so far there have been no terrorist attacks - nuclear explosions or “dirty bombs” (an ordinary explosion scattering radioactive dirt across the area is easier to make than a nuclear one, and the consequences are not much better). It turns out that at least once every 10 years a nuclear emergency occurs in the world: reactors explode, planes with warheads and satellites with reactors fall, and emissions occur. Perhaps you, as a patriot, will be pleased to know that half of all nuclear emergencies occur in our country; in this regard, we are ahead of the rest.

Filming tests in Nevada. USA, April 1952

Disinfection of settlements after the nuclear incident in Goiania. Brazil, 1987

Let's be realistic: no one will give up nuclear energy (in France, for example, nuclear plants provide 80% of the energy). And let's not be naive: accidents can happen in the future, it just makes sense to learn from mistakes. What can you do personally? Just two things.

Get a dosimeter. You live in Russia, where dosimeters, as fate would have it, are of the highest quality and cheapest. By God, you bought so much electronic waste and gadgets that not buying a dosimeter is simply stupid. The nicest of the simple ones is the Tolyatti SMG (from $100). Nuclear scientists consider the Lvov “Terra” (from $200) to be the most accurate and reliable. There are also all sorts of bluetooth dosimeters.

It is good to understand how radiation is dangerous and how it is not dangerous, so as not to succumb to global radiophobia.

What's next for us?

The list of the largest nuclear emergencies looks like this:

1945 - USA, bombing of the Japanese cities of Hiroshima and Nagasaki

1957 - USSR, accident at the Mayak plant

1957 - UK, Windscale reactor accident

1961 - USSR, accident on the K-19 submarine

1964 - USSR, fall of the Transit-5V satellite with a nuclear installation

1966 - Spain, destruction of three nuclear bombs in the village of Palomares

1968 - USA, destruction of four thermonuclear bombs in a plane crash over Greenland

1970 - USSR, accident at the Krasnoye Sormovo plant

1979 - USA, accident at the Three Mile Island nuclear power plant

1980 - USSR, radioactive contamination in Kramatorsk

1985 - USSR, accident in Chazhma Bay

1986 - USSR, Chernobyl accident

2011 - Japan, accident at the Fukushima-1 nuclear power plant

What is commonly called radiation is divided into three types: alpha -

α β γ Gamma rays and x-rays

Of the same nature as light and radio waves. Gamma rays penetrate everything through long distances. Water, concrete, and lead attenuate γ-radiation best. The natural cosmic background on the surface of the planet is about 0.11 microsievert. For an airplane that has gained altitude, the atmospheric layer ceases to act as a shield, so the natural cosmic background in the airplane reaches 3 millisieverts anywhere in the cabin, but this is not dangerous. All radiometers measure γ. Sources of γ-radiation: cesium-137, cobalt-60; X-ray hard radiation - americium-241.

Beta radiation

A stream of electrons or positrons that escape from an atom of a radioactive element. They fly close, so β ​​can only be detected at close range. By breaking into tissue, the particles cause more harm than gamma rays. A sheet of aluminum a couple of millimeters thick, window glass, and sometimes even clothing protect against β. It is believed that not all household radiometers are capable of measuring β, but they will still whistle when brought close. Sources of β-radiation: potassium-40, cesium-137, strontium-90; neutron - plutonium.

Alpha radiation

(uranium, radon, radium, thorium, polonium) - a helium atom flying away. From the point of view of atoms, the thing is quite large and, if it gets into tissue, it can do a lot of harm: the damage from α-radiation is 20 times greater than from γ-radiation. But α flies at a distance of several millimeters to several centimeters and is stopped even by a sheet of paper. It is believed that a household dosimeter is not capable of detecting α-radiation even when brought close. But α rarely goes alone; usually there are always admixtures of β and γ. Sources of α-radiation: radon, thoron, uranium.

Radiation becomes thousands of times more dangerous if particles enter the body through air, food, or become clogged with dust in the skin. From now on, this is a holiday that is always with you. The chance of receiving a dangerous dose in some way from the outside is minimal, unless you read a book under an X-ray lamp every day.

Gamma background

This is a natural thing, and it does not cause noticeable harm until its dose is exceeded a thousand, or even a million times.

Alpha and beta particles fly close and are stopped by anything. Therefore, in small doses they do not pose a threat to the body unless ingested. Once inside with food and air, the radioactive isotope remains in the body (sometimes forever) to systematically bombard surrounding tissues with particles. The totality of destruction leads to a variety of diseases, especially cancer: at some point the immune system does not have time to cope with its usual work - constantly identifying and removing damaged cells that have decided to become cancerous and begin endless growth.

History knows of cases when in areas considered radioactively contaminated, mortality, on the contrary, turned out to be noticeably lower than in ordinary ones. Frightened doctors so often dragged residents to medical examinations that early diagnosis and timely treatment brought more benefits to health than the purity of nature.

Discoverers

Pierre and Marie Curie in the laboratory, 1896

Radioactivity was discovered by Monsieur Becquerel in 1897, generally by accident: he was studying uranium salts and left the substance in a cabinet on a photographic plate. And later I noticed that the record itself lit up through the black wrapper. He shared his discovery with his colleagues - the spouses Pierre and Marie Curie, and they discovered radium and polonium. Becquerel discovered the dangers of radiation to health later, but in the same way: he borrowed a test tube of radium from Curie and carried it in his vest pocket, and later noticed a test-tube-shaped redness on the skin. He shared this again with Pierre Curie. He tied a test tube with a fair amount of radium to his shoulder and wore it for ten hours, earning a serious ulcer for the next couple of months.

Despite the fact that scientists have worked with radiation all their lives, it is wrong to think that radiation killed them. Becquerel died unexpectedly at the age of 55 (during a trip with his wife), and the cause of death is unknown. Pierre Curie, aged 46, slipped and was run over by a horse. Marie Curie, of course, died from leukemia caused by radiation - the pages of her laboratory diary are still so loud in the museum that it’s scary to approach them. But Maria died at 66 years old - she worked with radiation for more than 30 years after receiving the Nobel Prize for its discovery.

What should we do if these idiots have a problem again?

During a nuclear reaction (nuclear explosion or leak from a reactor), many different radioactive substances are synthesized that will harm all survivors. If you heard the roar of an explosion, then there are two good news: firstly, you are alive; secondly, all nuclear reactions have already ended. But the air was filled with radioactive volatile aerosols, and in a few hours all the sensors hundreds and thousands of kilometers away would scream from them.

Occurred on April 26, 1986 - a nuclear reactor exploded at the fourth power unit. The accident at the Chernobyl nuclear power plant was the largest disaster of our time in its long-term consequences. On April 25, 1986, the fourth unit of the Chernobyl nuclear power plant was supposed to be shut down for scheduled repairs, during which a check of the regulator’s operation was planned magnetic field one of two turbogenerators. These regulators were designed to extend the run-down time (idle operation) of the turbogenerator until standby diesel generators reach full power.

2 explosions occurred: 1 thermal - due to the explosion mechanism, nuclear - due to the nature of the stored energy.

2. chemical (the most powerful and destructive) – the energy of interatomic bonds is released

For an explosion at the Chernobyl nuclear power plant, there are two damaging factors: penetrating radiation and radioactive contamination.

Causes of the accident:

1. Design flaws of the reactor, gross errors in the work of personnel (switching off the emergency cooling system of the reactor)

2. Insufficient outside supervision government agencies and station management

3. Insufficient qualifications of personnel (lack of professionalism) and an imperfect security system

Radioactive contamination of the territory of the Republic of Belarus as a result of the Chernobyl accident, types of radionuclides and their half-life.

As a result of the accident, almost ¼ of the territory of the Republic of Belarus with a population of 2.2 million people was exposed to radioactive contamination. The Gomel, Mogilev and Brest regions were especially affected. Among the most polluted areas of the Gomel region are Braginsky, Kormyansky, Narovlyansky, Khoiniki. Vetkovsky and Chechersky. In the Mogilev region, the Krasnopolsky, Cherikovsky, Slavgorodsky, Bykhovsky and Kostyukovichsky districts are the most radioactively contaminated. In the Brest region the following areas are polluted: Luninets, Stolin, Pinsk and Drogichin districts. Radiation fallout was recorded in the Minsk and Grodno regions. Only the Vitebsk region is considered an almost clean region.

At first after the accident, the main contribution to the total radioactivity was made by short-lived radionuclides: iodine-131, strontium-89, tellurium-132 and others. Currently, pollution in our republic is determined mainly by cesium-137, and to a lesser extent by strontium-90 and plutonium radionuclides. This is explained by the fact that the more volatile cesium is carried over long distances. And the heavier ones, strontium and plutonium particles, settled closer to the Chernobyl nuclear power plant.

Due to the contamination of the territory, acreage was reduced, 54 collective and state farms were liquidated, and over 600 schools and kindergartens were closed. But the most severe consequences were for public health: the number of various diseases increased and life expectancy decreased.

Radionuclide type	Radiation	Half life
J131 (iodine)	emitter - β, gamma		(sorrel, milk, grain)
Cs137 (cesium) accumulates in muscles	emitter – β, gamma		a competitor that prevents the absorption of cesium into the body is potassium (lamb, potassium, beef, grain, fish)
Sr90 (strontium) accumulates in bones	emitter β		Competitor calcium (grain)
Pu239 (plutonium)	emitter – α, gamma, x-ray		competitor - iron (buckwheat, apples, pomegranate, liver)
Am241 (americium)	emitter - α, gamma

Characteristics of iodine-131 (accumulation in plants and animals), features of the effect on humans.

Iodine-131- radionuclide with a half-life of 8 days, beta and gamma emitter. Due to its high volatility, almost all of the iodine-131 present in the reactor was released into the atmosphere. Its biological effect is associated with the characteristics of the functioning thyroid gland. The thyroid gland of children is three times more active in absorbing radioiodine that enters the body. In addition, iodine-131 easily crosses the placenta and accumulates in the fetal gland.

The accumulation of large amounts of iodine-131 in the thyroid gland leads to radiation damage secretory epithelium and to hypothyroidism - thyroid dysfunction. The risk of malignant tissue degeneration also increases. In women, the risk of developing tumors is four times higher than in men, and in children it is three to four times higher than in adults.

The magnitude and rate of absorption, accumulation of radionuclide in organs, and rate of excretion from the body depend on age, gender, stable iodine content in the diet and other factors. In this regard, when the same amount of radioactive iodine enters the body, the absorbed doses differ significantly. Particularly large doses are formed in thyroid gland children, which is associated with the small size of the organ, and can be 2-10 times higher than the dose of radiation to the gland in adults.

Prevention of iodine-131 entry into the human body

Taking stable iodine preparations effectively prevents the entry of radioactive iodine into the thyroid gland. In this case, the gland is completely saturated with iodine and rejects radioisotopes that have entered the body. Taking stable iodine even 6 hours after a single dose of 131I can reduce the potential dose to the thyroid gland by approximately half, but if iodine prophylaxis is delayed for a day, the effect will be small.

Admission iodine-131 into the human body can occur mainly in two ways: inhalation, i.e. through the lungs, and orally through consumed milk and leafy vegetables.

Characteristics of strontium-90 (accumulation in plants and animals), features of the effect on humans.

A soft alkaline earth metal with a silvery-white color. It is very chemically active and reacts quickly with moisture and oxygen in air, becoming covered with a yellow oxide film

Stable strontium isotopes themselves are of little danger, but radioactive strontium isotopes pose a great danger to all living things. The radioactive isotope of strontium strontium-90 is rightfully considered one of the most terrible and dangerous anthropogenic radiation pollutants. This is due, first of all, to the fact that it has a very short half-life - 29 years, which makes it very high level its activity and powerful radiation, and on the other hand, its ability to be effectively metabolized and included in the life of the body.

Other abstracts:

• Conditions for fulfilling standards and training tasks for tactical and special training

• Definition of concepts: radiation safety; radionuclides, ionizing radiation
• Corpuscular radiation (α, β, neutron) and its characteristics, the concept of induced radioactivity.

The horizon is improving. Salt and iodine in the air.

Where does iodine come from in the air?

Iodine is a rather rare element: in earth's crust there is very little of it - only 0.00005%, this is four times less than arsenic, five times less than bromine. Iodine is a halogen (in Greek hals - salt, genos - origin). Indeed, in nature, all halogens are found exclusively in the form of salts. But if fluorine and chlorine minerals are very common, then iodine’s own minerals (lautarite Ca(IO 3) 2, iodargyrite AgI) are extremely rare. Iodine is usually found among other salts as an impurity. An example is natural sodium nitrate - Chilean saltpeter, which contains an admixture of sodium iodate NaIO 3. Deposits of Chilean saltpeter began to be developed at the beginning of the 19th century. After dissolving the rock in hot water, the solution was filtered and cooled. At the same time, pure sodium nitrate precipitated, which was sold as fertilizer. Iodine was extracted from the solution remaining after crystallization. In the 19th century, Chile became the main supplier of this rare element.

Sodium iodate is quite soluble in water: 9.5 g per 100 g of water at 25 o C. Sodium iodide NaI is much more soluble: 184 g per 100 g of water! Iodine in rocks is most often found in the form of easily soluble inorganic salts and therefore can be leached from them by groundwater. And then it enters rivers, seas and oceans, where it accumulates by certain organisms, including algae. For example, 1 kg of dried seaweed (kelp) contains 5 g of iodine, while 1 kg of sea water contains only 0.025 mg, that is, 200 thousand times less! It is not for nothing that in some countries iodine is still extracted from kelp, and the sea air (this is what Brodsky had in mind) has a special smell; Sea salt also always contains some iodine. Winds that carry air masses from the ocean to the mainland also carry iodine. In coastal areas, the amount of iodine in 1 cubic meter. m of air can reach 50 micrograms, while in continental and mountainous areas it is only 1 or even 0.2 micrograms.

Nowadays, iodine is extracted mainly from the waters of oil and gas fields, and the need for it is quite high. More than 15,000 tons of iodine are mined annually around the world.

Discovery and properties of iodine.

Iodine was first obtained from seaweed ash by the French chemist Bernard Courtois in 1811. This is how he described the properties of the element he discovered: “The new substance precipitates in the form of a black powder, which turns into a magnificent purple vapor when heated. These vapors condense in the form of shiny crystalline plates that have a shine... The amazing color of the vapors of the new substance makes it possible to distinguish it from all hitherto known substances...” Iodine got its name from the color of the vapor: in Greek “iodes” means purple.

Courtois observed another unusual phenomenon: solid iodine did not melt when heated, but immediately turned into steam; this process is called sublimation. D.I. Mendeleev in his chemistry textbook describes this process as follows: “To purify iodine, it is sublimated... iodine goes directly from the vapor into a crystalline state and settles in the cooled parts of the apparatus in the form of lamellar crystals, having a blackish-gray color and metallic shine". But if iodine crystals are heated quickly in a test tube (or iodine vapor is not allowed to escape), then at a temperature of 113 o C the iodine will melt, turning into a black-violet liquid. This is explained by the fact that at the melting temperature the vapor pressure of iodine is high - about 100 mm Hg (1.3H 10 4 Pa). And if there is not enough vapor above the heated solid iodine, it will evaporate faster than it melts.

In its pure form, iodine is black-gray heavy (density 4.94 g/cm3) crystals with a violet metallic luster. Why is iodine tincture not purple? It turns out that iodine has a different color in different solvents: in water it is yellow, in gasoline, carbon tetrachloride CCl 4, and many other so-called “inert” solvents it is purple - exactly the same as iodine vapor. A solution of iodine in benzene, alcohol and a number of other solvents has a brown-brown color (like iodine tincture); in an aqueous solution of polyvinyl alcohol (–CH 2 –CH(OH)–) n iodine has a bright blue color (this solution is used in medicine as a disinfectant called “iodinol”; it is used to gargle and wash wounds). And here’s what’s curious: the reactivity of iodine in “multi-colored” solutions is not the same! So, in brown solutions, iodine is much more active than in purple ones. If copper powder or a piece of thin copper foil is added to a 1% brown solution, it will become discolored in 1–2 minutes as a result of the reaction 2Cu + I 2 ® 2CuI. The purple solution will remain unchanged under these conditions for several tens of minutes. Calomel (Hg 2 Cl 2) discolors a brown solution in a few seconds, but a violet solution in only two minutes. These experiments are explained by the fact that iodine molecules can interact with solvent molecules, forming complexes in which iodine is more active.

A blue color also appears when iodine reacts with starch. You can verify this by dropping iodine tincture on a slice of potato or on a piece of white bread. This reaction is so sensitive that with the help of iodine it is easy to detect starch on a fresh cut of a potato or in flour. Back in the 19th century. this reaction was used to convict unscrupulous traders who added wheat flour to sour cream “for thickness.” If you drop iodine tincture onto a sample of such sour cream, the blue color will immediately reveal the deception.

To remove stains from iodine tincture, you need to use a solution of sodium thiosulfate, which is used in photography and sold in photographic stores (it is also called “fixer” and “hyposulfite”). Thiosulfate instantly reacts with iodine, completely discoloring it: I 2 + 2Na 2 S 2 O 3 ® 2NaI + Na 2 S 4 O 6. It is enough to wipe the skin or fabric stained with iodine with an aqueous solution of thiosulfate, and the yellow-brown stain will immediately disappear.

Iodine in the first aid kit.

In the minds of an ordinary person (not a chemist), the word “iodine” is associated with a bottle that is in the first aid kit. In fact, the bottle contains not iodine, but an iodine tincture - a 5% solution of iodine in a mixture of alcohol and water (potassium iodide is also added to the tincture; it is needed so that the iodine dissolves better). Previously, iodoform (triiodomethane CHI 3), a disinfectant with an unpleasant odor, was also widely used in medicine. Preparations containing iodine have antibacterial and antifungal properties, they also have an anti-inflammatory effect; They are used externally to disinfect wounds in preparation for operations.

Iodine is poisonous. Even such a familiar iodine tincture, when inhaled its vapors, affects the upper respiratory tract, and if ingested, causes severe burns of the digestive tract. Long-term introduction of iodine into the body, as well as increased sensitivity to it, can cause a runny nose, hives, salivation and lacrimation, and acne.

Iodine in the body.

Here are the lines of another poet, Bella Akhmadulina:

...Was it a strong spirit that ordered us to look for an outcome,

Is it a weak thyroid gland?

begged for the bitter delicacies of iodine?

Why does the thyroid gland need this “delicacy”?

As a rule, only “light” elements found in the first third of the periodic table participate in biochemical processes. Almost the only exception to this rule is iodine. A person contains about 20 to 50 mg of iodine, a significant part of which is concentrated in the thyroid gland (the rest of the iodine is in the blood plasma and muscles).

The thyroid gland was already known to doctors ancient times, who deservedly attributed to it an important role in the body. It is shaped like a bow tie, i.e. consists of two lobes connected by an isthmus. The thyroid gland releases hormones into the blood that have a very diverse effect on the body. Two of them contain iodine - thyroxine (T4) and triiodothyronine (T3). The thyroid gland regulates the development and growth of both individual organs and the entire organism as a whole, and adjusts the speed of metabolic processes.

IN food products and in drinking water, iodine is contained in the form of salts of hydroiodic acid - iodides, from which it is easily absorbed in the anterior sections of the small intestine. From the intestines, iodine passes into the blood plasma, from where it is greedily absorbed by the thyroid gland. There it is converted into the most important thyroid hormones for the body (from the Greek thyreoeides - thyroid). This process is complex. First, I – ions are enzymatically oxidized to I + . These cations react with the protein thyroglobulin, which contains many amino acid tyrosine residues. Under the action of the enzyme iodinase, iodination of the benzene rings of tyrosine occurs with the subsequent formation of thyroid hormones. Currently, they are obtained synthetically, and in structure and action they are no different from natural ones.

If the synthesis of thyroid hormones slows down, a person develops goiter. The disease is caused by a lack of iodine in the soil, water and, consequently, in plants, animals and foods produced in the area. Such a goiter is called endemic, i.e. characteristic of a given area (from the Greek endemos - local). Areas of iodine deficiency are quite common. As a rule, these are areas remote from the ocean or fenced off from sea winds by mountains. Thus, a significant part of the world's soil is poor in iodine, and accordingly, food products are poor in iodine. In Russia, iodine deficiency occurs in mountainous areas; Extremely pronounced iodine deficiency was detected in the Republic of Tuva, as well as in Transbaikalia. There is little of it in the Urals, Upper Volga, Far East, Mari and Chuvash Republics. Not all is well in iodine in a number of central regions - Tula, Bryansk, Kaluga, Oryol, and other regions. Drinking water, plants and animals in these areas have low iodine content. The thyroid gland, as if compensating for the insufficient supply of iodine, grows - sometimes to such a size that the neck is deformed, blood vessels, nerves, and even the bronchi and esophagus are compressed. Endemic goiter can be easily prevented by replenishing iodine deficiency in the body.

If there is a lack of iodine during pregnancy in the mother, as well as in the first period of the child’s life, his growth slows down, mental activity decreases, cretinism, deaf-muteness and other severe developmental disorders may develop. Timely diagnosis helps to avoid these misfortunes by simply administering thyroxine.

Lack of iodine in adults leads to a decrease in heart rate and body temperature - patients feel cold even in hot weather. Their immunity decreases, hair falls out, movement and even speech slow down, their face and limbs swell, they experience weakness, fatigue, drowsiness, memory impairment, and indifference to the world around them. The disease is also treated with T3 and T4 drugs. In this case, all of the listed symptoms disappear.

Where to get iodine.

To prevent endemic goiter, iodine is introduced into food products. The most common method is iodization of table salt. Usually potassium iodide is introduced into it - approximately 25 mg per 1 kg. However, KI in moist warm air is easily oxidized to iodine, which volatilizes. This explains the short shelf life of such salt - only 6 months. Therefore, recently potassium iodide has been replaced by KIO 3 iodate. In addition to table salt, iodine is added to a number of vitamin mixtures.

Iodized products are not necessary for those who consume enough iodine in food and water. The need for iodine for an adult depends little on gender and age and is approximately 150 mcg per day (however, it increases during pregnancy, increased growth, and cooling). Most foods contain very little iodine. For example, bread and pasta typically contain less than 5 mcg; in vegetables and fruits - from 1–2 mcg in apples, pears and black currants to 5 mcg in potatoes and up to 7–8 mcg in radishes and grapes; in chickens and beef – up to 7 mcg. And this is per 100 g of dry product, i.e. ash! Moreover, during long-term storage or heat treatment, from 20 to 60% of iodine is lost. But fish, especially sea fish, are rich in iodine: in herring and pink salmon there is 40–50 mcg, in cod, pollock and hake – up to 140–160 (also per 100 g of dry product). There is much more iodine in cod liver - up to 800 mcg, but there is especially a lot of it in brown seaweed - “seaweed” (aka kelp) - it can contain up to 500,000 mcg of iodine! In our country, kelp grows in the White, Barents, Japanese and Okhotsk seas.

Also in Ancient China seaweed successfully treated thyroid diseases. In the coastal regions of China, there was a tradition - after giving birth, women were given seaweed. At the same time, the mother's milk was complete, and the child grew up healthy. In the 13th century they even issued a decree obliging all citizens to eat seaweed to improve their health. Eastern healers claim that after 40 years, seaweed products must be present in the diet of even healthy people. Some explain the longevity of the Japanese people by eating kelp, as well as the fact that after the nuclear bombings of Hiroshima and Nagasaki, the number of deaths as a result of environmental contamination with radioactive substances was relatively small.

Iodine and radiation.

In nature, iodine is represented by the only stable isotope 127I.

Artificial radioactive isotopes of iodine - 125 I, 131 I, 132 I and others are widely used in biology and, especially, in medicine to determine the functional state of the thyroid gland and treat a number of its diseases. The use of radioactive iodine in diagnostics is associated with the ability of iodine to selectively accumulate in the thyroid gland; use for medicinal purposes is based on the ability of radiation from iodine radioisotopes to destroy diseased gland cells.

When the environment is contaminated with nuclear fission products, radioactive isotopes of iodine quickly enter the biological cycle, ultimately ending up in milk and, consequently, in the human body. Thus, many residents of areas affected by nuclear explosion in Chernobyl, received a hefty dose of radioactive iodine-131 (half-life 8 days) and damaged the thyroid gland. Most of the patients were in areas where there was little natural iodine and residents were not protected by “ordinary iodine.” “Radioiodine” is especially dangerous for children, whose thyroid gland is 10 times smaller than that of adults and has greater radiosensitivity, which can lead to thyroid cancer.

To protect the thyroid gland from radioactive iodine, it is recommended to use regular iodine preparations (100–200 mg per dose), which “blocks” the thyroid gland from radioiodine entering it. Radioactive iodine not absorbed by the thyroid gland is almost completely and relatively quickly excreted in the urine. Fortunately, radioactive iodine does not last long, and after 2-3 months it almost completely disintegrates.

Iodine in technology.

Significant quantities of mined iodine are used to obtain high-purity metals. This purification method is based on the so-called halogen cycle, discovered in 1915 by the American physical chemist Irving Langmuir (1881–1957). The essence of the halogen cycle can be explained using the example of a modern method for producing high-purity titanium metal. When titanium powder is heated in a vacuum in the presence of iodine to a temperature above 400 o C, gaseous titanium (IV) iodide is formed. It is passed over a titanium wire heated by current to 1100–1400 o C. At such a high temperature, TiI 4 cannot exist and decomposes into metallic titanium and iodine; pure titanium condenses on the wire in the form of beautiful crystals, and the released iodine can again react with the titanium powder, turning it into volatile iodide. The iodide method can be used to purify various metals - copper, nickel, iron, chromium, zirconium, hafnium, vanadium, niobium, tantalum, etc.

The same cycle is carried out in halogen lamps. In conventional lamps, the efficiency is extremely low: in a burning lamp, almost all the electrical energy is converted not into light, but into heat. To increase the light output of a lamp, it is necessary to increase the temperature of its coil as much as possible. But at the same time, the life of the lamp is significantly reduced: the spiral in it quickly burns out. If you introduce a very small amount of iodine (or bromine) into the lamp flask, then as a result of the halogen cycle, tungsten, evaporated from the coil and deposited on the inner surface of the glass flask, is again transferred to the coil. In such a lamp, you can significantly - by hundreds of degrees - increase the temperature of the coil, bringing it to 3000 o C, which doubles the light output. A powerful halogen lamp looks like a midget compared to a conventional lamp of the same power. For example, a 300-watt halogen lamp has a diameter of less than 1.5 cm.

An increase in the temperature of the coil inevitably leads to stronger heating of the bulbs in halogen lamps. Simple glass cannot withstand such temperatures, so you have to place the spiral in a quartz glass tube. The first patents for halogen lamps were issued only in 1949, and their industrial production was launched even later. The technical development of quartz lamps with a self-healing tungsten filament was carried out in 1959 by General Electric. In such lamps the cylinder can heat up to 1200 o C! Halogen lamps have excellent light characteristics, so these lamps, despite their high cost, are widely used wherever a powerful and compact light source is needed - in film projectors, car headlights, etc.

Iodine compounds are also used to cause rain. Rain, like snow, begins with the formation of tiny ice crystals from water vapor in the clouds. Further, these embryonic crystals grow quickly, become heavy and fall out in the form of precipitation, turning, depending on weather conditions, into snow, rain or hail. If the air is absolutely clean, ice nuclei can only form at very low temperatures (below –30 o C). In the presence of certain substances, ice nuclei form at a much higher temperature. This way you can cause artificial snowfall (or rain).

One of the best seeds is silver iodide; in its presence, ice crystals begin to grow already at –9 o C. It is significant that the smallest particles of silver iodide with a size of only 10 nm (1 nm = 10 –9 m) can “work”. For comparison, the radii of silver and iodine ions are 0.15 and 0.22 nm, respectively. Theoretically, from a cubic crystal of AgI just 1 cm in size, 10 21 such tiny particles, and it will not seem surprising that very little silver iodide is required to produce artificial rain. As American meteorologists have calculated, only 50 kg of AgI is enough to “seed” the entire atmosphere above the surface of the United States (which is 9 million square kilometers)! Moreover, in 1 cubic. m, over 3.5 million centers of ice crystallization are formed. And to support the formation of ice nuclei, it is enough to consume only 0.5 kg of AgI per hour. Therefore, despite the relatively high cost of silver salts, the use of AgI to induce artificial rain turns out to be practically profitable.

Sometimes it is necessary to perform the exact opposite task: to “disperse” the clouds, to prevent rain from falling during any important event (for example, the Olympic Games). In this case, silver iodide must be sprayed into the clouds in advance, tens of kilometers from the venue of the celebration. Then the rain will pour on the forests and fields, and the city will have sunny, dry weather.

Ilya Leenson