Activity of a radioactive substance. Application of radioactive isotopes. Applications of radioactivity

Radioactive radiation (or ionizing radiation) is energy that is released by atoms in the form of particles or waves of an electromagnetic nature. Humans are exposed to such exposure through both natural and anthropogenic sources.

The beneficial properties of radiation have made it possible to successfully use it in industry, medicine, scientific experiments and research, agriculture and other fields. However, with the spread of this phenomenon, a threat to human health has arisen. A small dose of radioactive radiation can increase the risk of acquiring serious diseases.

The difference between radiation and radioactivity

Radiation, in a broad sense, means radiation, that is, the spread of energy in the form of waves or particles. Radioactive radiation is divided into three types:

• alpha radiation – flux of helium-4 nuclei;
• beta radiation – flow of electrons;
• Gamma radiation is a stream of high-energy photons.

The characteristics of radioactive radiation are based on their energy, transmission properties and the type of emitted particles.

Alpha radiation, which is a stream of corpuscles with a positive charge, can be delayed by thick air or clothing. This species practically does not penetrate the skin, but when it enters the body, for example, through cuts, it is very dangerous and has a detrimental effect on internal organs.

Beta radiation has more energy - electrons move at high speeds and are small in size. Therefore, this type of radiation penetrates through thin clothing and skin deep into the tissue. Beta radiation can be shielded using an aluminum sheet a few millimeters thick or a thick wooden board.

Gamma radiation is high-energy radiation of an electromagnetic nature that has a strong penetrating ability. To protect against it, you need to use a thick layer of concrete or a plate of heavy metals such as platinum and lead.

The phenomenon of radioactivity was discovered in 1896. The discovery was made by the French physicist Becquerel. Radioactivity is the ability of objects, compounds, elements to emit ionizing radiation, that is, radiation. The reason for the phenomenon is the instability of the atomic nucleus, which releases energy during decay. There are three types of radioactivity:

• natural – typical for heavy elements whose serial number is greater than 82;
• artificial – initiated specifically with the help of nuclear reactions;
• induced - characteristic of objects that themselves become a source of radiation if they are heavily irradiated.

Elements that are radioactive are called radionuclides. Each of them is characterized by:

• half-life;
• type of radiation emitted;
• radiation energy;
• and other properties.

Sources of radiation

The human body is regularly exposed to radioactive radiation. Approximately 80% of the amount received each year comes from cosmic rays. Air, water and soil contain 60 radioactive elements that are sources of natural radiation. The main natural source of radiation is considered to be the inert gas radon, released from the earth and rocks. Radionuclides also enter the human body through food. Some of the ionizing radiation to which people are exposed comes from man-made sources, ranging from nuclear electricity generators and nuclear reactors to radiation used for medical treatment and diagnostics. Today, common artificial sources of radiation are:

• medical equipment (the main anthropogenic source of radiation);
• radiochemical industry (extraction, enrichment of nuclear fuel, processing of nuclear waste and its recovery);
• radionuclides used in agriculture and light industry;
• accidents at radiochemical plants, nuclear explosions, radiation releases
• Construction Materials.

Based on the method of penetration into the body, radiation exposure is divided into two types: internal and external. The latter is typical for radionuclides dispersed in the air (aerosol, dust). They get on your skin or clothing. In this case, radiation sources can be removed by washing them away. External radiation causes burns to the mucous membranes and skin. In the internal type, the radionuclide enters the bloodstream, for example by injection into a vein or through a wound, and is removed by excretion or therapy. Such radiation provokes malignant tumors.

The radioactive background significantly depends on the geographical location - in some regions the level of radiation can exceed the average by hundreds of times.

The effect of radiation on human health

Radioactive radiation, due to its ionizing effect, leads to the formation of free radicals in the human body - chemically active aggressive molecules that cause cell damage and death.

Cells of the gastrointestinal tract, reproductive and hematopoietic systems are especially sensitive to them. Radioactive radiation disrupts their work and causes nausea, vomiting, bowel dysfunction, and fever. By affecting the tissues of the eye, it can lead to radiation cataracts. The consequences of ionizing radiation also include damage such as vascular sclerosis, deterioration of immunity, and damage to the genetic apparatus.

The system of transmission of hereditary data has a fine organization. Free radicals and their derivatives can disrupt the structure of DNA, the carrier of genetic information. This leads to mutations that affect the health of subsequent generations.

The nature of the effects of radioactive radiation on the body is determined by a number of factors:

• type of radiation;
• radiation intensity;
• individual characteristics of the body.

The effects of radioactive radiation may not appear immediately. Sometimes its consequences become noticeable after a significant period of time. Moreover, a large single dose of radiation is more dangerous than long-term exposure to small doses.

The amount of radiation absorbed is characterized by a value called Sievert (Sv).

• Normal background radiation does not exceed 0.2 mSv/h, which corresponds to 20 microroentgens per hour. When X-raying a tooth, a person receives 0.1 mSv.

• The lethal single dose is 6-7 Sv.

Application of ionizing radiation

Radioactive radiation is widely used in technology, medicine, science, military and nuclear industries and other areas of human activity. The phenomenon underlies devices such as smoke detectors, power generators, icing alarms, and air ionizers.

In medicine, radioactive radiation is used in radiation therapy to treat cancer. Ionizing radiation has made it possible to create radiopharmaceuticals. With their help, diagnostic examinations are carried out. Instruments for analyzing the composition of compounds and sterilization are built on the basis of ionizing radiation.

The discovery of radioactive radiation was, without exaggeration, revolutionary - the use of this phenomenon brought humanity to a new level of development. However, this also caused a threat to the environment and human health. In this regard, maintaining radiation safety is an important task of our time.

radiation particle irradiation radon

People have learned to use radiation for peaceful purposes, with a high level of safety, which has made it possible to raise almost all industries to a new level.

Producing energy using nuclear power plants. Of all branches of human economic activity, energy has the greatest impact on our lives. Heat and light in homes, traffic flows and the operation of industry - all this requires energy. This industry is one of the fastest growing. Over 30 years, the total capacity of nuclear power units has increased from 5 thousand to 23 million kilowatts.

Few people doubt that nuclear energy has taken a strong place in the energy balance of humanity.

Let's consider the use of radiation in flaw detection. X-ray and gamma flaw detection are one of the most common uses of radiation in industry to control the quality of materials. The X-ray method is non-destructive, so that the material being tested can then be used for its intended purpose. Both X-ray and gamma flaw detection are based on the penetrating ability of X-ray radiation and the characteristics of its absorption in materials.

Gamma radiation is used for chemical transformations, for example, in polymerization processes.

Perhaps one of the most important developing industries is nuclear medicine. Nuclear medicine is a branch of medicine associated with the use of achievements of nuclear physics, in particular radioisotopes, etc.

Today, nuclear medicine makes it possible to study almost all human organ systems and is used in neurology, cardiology, oncology, endocrinology, pulmonology and other areas of medicine.

Using nuclear medicine methods, the blood supply to organs, bile metabolism, kidney, bladder, and thyroid function are studied.

It is possible not only to obtain static images, but also to overlay images obtained at different points in time to study dynamics. This technique is used, for example, in assessing heart function.

In Russia, two types of diagnostics using radioisotopes are already actively used - scintigraphy and positron emission tomography. They allow you to create complete models of organ function.

Doctors believe that at low doses, radiation has a stimulating effect, training the human biological defense system.

Many resorts use radon baths, where the level of radiation is slightly higher than in natural conditions.

It has been noticed that those who take these baths have improved performance, calmed the nervous system, and healed injuries faster.

Research by foreign scientists suggests that the incidence and mortality from all types of cancer are lower in areas with a higher natural background radiation (most sunny countries include these).

Medicine. Radium and other naturally occurring radioisotopes are widely used in the diagnosis and radiation therapy of cancer. The use of artificial radioisotopes for this purpose has significantly increased the effectiveness of treatment. For example, radioactive iodine, introduced into the body in the form of a solution of sodium iodide, selectively accumulates in the thyroid gland and is therefore used in clinical practice to determine dysfunction of the thyroid gland and in the treatment of Graves' disease. Using sodium-labeled saline, the rate of blood circulation is measured and the patency of the blood vessels of the extremities is determined. Radioactive phosphorus is used to measure blood volume and treat erythremia.

Scientific research. Radioactive tracers, introduced in micro quantities into physical or chemical systems, make it possible to monitor all changes occurring in them. For example, by growing plants in an atmosphere of radioactive carbon dioxide, chemists were able to understand the subtle details of how plants form complex carbohydrates from carbon dioxide and water. As a result of the continuous bombardment of the earth's atmosphere by high-energy cosmic rays, the nitrogen-14 found in it, capturing neutrons and emitting protons, turns into radioactive carbon-14. Assuming that the intensity of bombardment and, therefore, the equilibrium amount of carbon-14 has remained unchanged in recent millennia, and taking into account the half-life of C-14 from its residual activity, it is possible to determine the age of the found remains of animals and plants (radiocarbon dating). This method made it possible to date with great certainty the discovered sites of prehistoric man that existed more than 25,000 years ago.

Wilson chamber(aka fog chamber) - one of the first instruments in history for recording traces (tracks) of charged particles.

Invented by Scottish physicist Charles Wilson between 1910 and 1912. The operating principle of the camera uses the phenomenon of condensation of supersaturated steam: when any condensation centers appear in the medium of supersaturated steam (in particular, ions accompanying the trace of a fast charged particle), small drops of liquid form on them. These droplets reach significant sizes and can be photographed. The source of the particles under study can be located either inside the chamber or outside it (in this case, the particles fly through a window that is transparent to them).

In 1927, Soviet physicists P. L. Kapitsa D. V. Skobeltsyn proposed placing a camera in a strong magnetic field that bends the tracks to study the quantitative characteristics of particles (for example, mass and speed).

A cloud chamber is a container with a glass lid and a piston at the bottom, filled with saturated vapor of water, alcohol or ether. The vapors are thoroughly cleaned of dust so that there are no condensation centers for water molecules before the particles fly by. When the piston is lowered, due to adiabatic expansion the vapor cools and becomes supersaturated. A charged particle passing through the chamber leaves a chain of ions along its path. The vapor condenses on the ions, making the particle's trail visible.

The cloud chamber played a huge role in studying the structure of matter. For several decades, it remained practically the only instrument for the visual study of nuclear radiation and cosmic ray research:

In 1930, L.V. MysovskysR. A. Eichelberger conducted experiments with rubidium in a cloud chamber and recorded the emission of β-particles. Later, the natural radioactivity of the isotope 87 Rb was discovered.

In 1934, L. V. Mysovsky with M. S. Eigenson conducted experiments in which, using a cloud chamber, the presence of neutrons in the composition of cosmic rays was proven.

In 1927, Wilson received the Nobel Prize in Physics for his invention. Subsequently, the cloud chamber gave way to bubble spark chambers as the main means of studying radiation.

Introduction………………………………………………………………………………3

Application of radioactive sources in various

spheres of human activity……………………………………………………….3

Chemical industry

Urban economy

Medical industry

Radiation sterilization of products and materials

Production of radioisotope pacemakers

Pre-sowing irradiation of seeds and tubers

Radioisotope diagnostics (introduction of a radioactive drug into the body)

Radioactive waste, problems of their disposal…………………..8

Lack of development of the method………………………………………………………...12

Pressure from external circumstances………………………………………………………..13

Decision making and technological complexity of the problem………………………...13

Uncertainty of the concept………………………………………………………...14

References……………………………………………………….16

Introduction

Currently, it is difficult to find a branch of science, technology, industry, agriculture and medicine where sources of radioactivity (radioactive isotopes) are not used. Artificial and natural radioactive isotopes are a powerful and subtle tool for creating sensitive methods of analysis and control in industry, a unique tool for medical diagnosis and treatment of malignant tumor diseases, and an effective means of influencing various substances, including organic ones. The most important results were obtained using isotopes as radiation sources. The creation of installations with powerful sources of radioactive radiation made it possible to use it to monitor and control technological processes; technical diagnostics; therapy of human diseases; obtaining new properties of substances; converting the decay energy of radioactive substances into heat and electricity, etc. Most often for these purposes, isotopes such as ⁶⁰CO, ⁹⁰Sr, ¹³⁷Cs and plutonium isotopes are used. To prevent sources from depressurizing, they are subject to strict requirements for mechanical, thermal and corrosion resistance. This provides a guarantee of maintaining tightness throughout the entire period of operation of the source.

The use of radioactive sources in various fields of human activity.

Chemical industry

Radiation-chemical modification of polyamide fabric to give it hydrophilic and antistatic properties.

Modification of textile materials to obtain wool-like properties.

Obtaining cotton fabrics with antimicrobial properties.

Radiation modification of crystal to produce crystal products of various colors.

Radiation vulcanization of rubber-fabric materials.

Radiation modification of polyethylene pipes to increase heat resistance and resistance to aggressive environments.

Hardening of paint and varnish coatings on various surfaces.

Wood industry

As a result of irradiation, soft wood acquires a significantly low ability to absorb water, high stability of geometric dimensions and higher hardness (production of mosaic parquet).

Urban economy

Radiation treatment and disinfection of wastewater.

Medical industry

Radiation sterilization of products and materials

The range of radiation-sterilizable products includes over a thousand items, including disposable syringes, blood service systems, medical instruments, suture and dressing materials, various prostheses used in cardiovascular surgery, traumatology and orthopedics. The main advantage of radiation sterilization is that it can be carried out continuously at high throughput. Suitable for sterilization of finished products packaged in transport containers or secondary packaging, and also applicable for sterilization of thermolabile products and materials.

Production of radioisotope pacemakers with power supplies based on ²³⁸Pu. Implanted into the human body, they are used to treat various heart rhythm disorders that are not amenable to medication. The use of a radioisotope power source increases their reliability, increases their service life to 20 years, and returns patients to normal life by reducing the number of repeated operations to implant a pacemaker.

Agriculture and food industry

Agriculture is an important area of ​​application of ionizing radiation. To date, in agricultural practice and agricultural scientific research, the following main areas of use of radioisotopes can be distinguished:

Irradiation of agricultural objects (primarily plants) with a low dose in order to stimulate their growth and development;

Application of ionizing radiation for radiation mutagenesis and plant selection;

Using the method of radiation sterilization to combat insect pests of agricultural plants.

Pre-sowing irradiation of seeds and tubers(wheat, barley, corn, potatoes, beets, carrots) leads to improved sowing qualities of seeds and tubers, acceleration of plant development processes (precocity), and increases plant resistance to adverse environmental factors.

In the field of breeding, mutagenesis research is being carried out. The goal is to select macromutations for the development of high-yielding varieties. Radiation mutants of interest have already been obtained for more than 50 crops.

The use of ionizing radiation to sterilize insect pests in elevators and granaries can reduce crop losses by up to 20%.

Known that ionizing γ-radiation prevents the germination of potatoes and onions, is used for disinfestation of dried fruits, food concentrates, slows down microbiological spoilage and extends the shelf life of fruits, vegetables, meat, and fish. The possibility of accelerating the aging process of wines and cognac, changing the rate of fruit ripening, and removing the unpleasant odor of medicinal waters has been identified. In the canning industry (fish, meat and dairy, vegetables and fruit), sterilization of canned food is widely used. It should be noted that a study of irradiated food products showed that γ-irradiated products are harmless.

We examined the use of radioisotopes specific to individual industries. In addition, radioisotopes are used throughout industry for the following purposes:

Measuring levels of liquid melts;

Measurement of densities of liquids and pulps;

Counting items on a container;

Measuring the thickness of materials;

Measuring ice thickness on aircraft and other vehicles;

Measurement of density and moisture content of soils;

Non-destructive γ-flaw detection of product materials.

Radioisotope therapeutic devices, as well as clinical radioisotope diagnostics, have found clinical use directly in medical practice.

γ-therapeutic devices for external γ-irradiation have been mastered. These devices have significantly expanded the possibilities of remote γ -therapy of tumors through the use of static and mobile irradiation options.

Various options and methods of radiation treatment are used for individual tumor locations. Persistent five-year cures for stages 1, 2 and 3 were obtained, respectively, in

90-95, 75-85 and 55-60% of patients. The positive role of radiation therapy in the treatment of cancer of the breast, lung, esophagus, oral cavity, larynx, bladder and other organs is also well known.

Radioisotope diagnostics (introduction of a radioactive drug into the body) has become an integral part of the diagnostic process at all stages of disease development or assessment of the functional state of a healthy organism. Radioisotope diagnostic studies can be reduced to the following main sections:

Determination of radioactivity of the whole body, its parts, individual organs in order to identify the pathological condition of the organ;

Determination of the speed of movement of a radioactive drug through individual areas of the cardiovascular system;

Study of the spatial distribution of a radioactive drug in the human body for visualization of organs, pathological formations, etc.

The most important aspects of diagnosis include pathological changes in the cardiovascular system, timely detection of malignant neoplasms, assessment of the state of the bone, hematopoietic and lymphatic systems of the body, which are difficult to access objects for research using traditional clinical and instrumental methods.

Nay labeled with ¹³y has been introduced into clinical practice for the diagnosis of thyroid diseases; NaCe labeled with ²⁴Na for studying local and general blood flow;

Na₃PO₄, labeled with ³³P to study the processes of its accumulation in pigmented skin formations and other tumor formations.

The diagnostic method in neurology and neurosurgery using the isotopes ⁴⁴Tc, ¹³³Xe and ¹⁶⁹Y has gained leading importance. It is necessary for a more precise diagnosis of brain diseases, as well as diseases of the cardiovascular system. In nephrology and urology, radioactive drugs containing ¹³¹Y, ¹⁹⁷Hg,

¹⁶⁹Yb, ⁵¹Cr and ¹¹³Yn. Thanks to the introduction of radioisotope examination methods, early morbidity of the kidneys and other organs has improved.

The scientific and applied applications of p/isotopes are very wide. Let's look at a few:

Of practical interest is the use of radioisotope power plants (RPUs) with electrical power from several units to hundreds of watts. The greatest practical application has been found in radioisotope thermoelectric generators, in which the conversion of radioactive decay energy into electrical energy is carried out using thermoelectric converters; such power plants are characterized by complete autonomy, the ability to operate in any climatic conditions, a long service life and operational reliability.

Radioisotope power supplies provide operation in systems of automatic weather stations; in navigation equipment systems in remote and uninhabited areas (electric power supply to lighthouses, directional signs, navigation lights).

Thanks to the positive experience of using them in low temperature conditions, it became possible to use them in Antarctica.

It is also known that isotope power plants with ²¹ºPo were used on vehicles moving on the surface of the Moon (lunar rovers).

The use of r/a isotopes in scientific research cannot be overestimated, since all practical methods follow from positive results in research.

In addition, it is worth mentioning such very narrow specializations as pest control in ancient objects of art, as well as the use of natural radioactive isotopes in radon baths and mud during spa treatment.

At the end of their service life, radioactive sources must be delivered in the prescribed manner to special plants for processing (conditioning) with subsequent disposal as radioactive waste.

Radioactive waste, problems of their disposal

The problem of radioactive waste is a special case of the general problem of environmental pollution by human waste. But at the same time, the pronounced specificity of radioactive waste requires the use of specific methods to ensure safety for humans and the biosphere.

The historical experience of handling industrial and household waste was formed in conditions when awareness of the danger of waste and programs for its neutralization was based on direct sensations. The capabilities of the latter ensured the adequacy of awareness of the connections between influences directly perceived by the senses and the upcoming consequences. The level of knowledge made it possible to present the logic of the mechanisms of the impact of waste on humans and the biosphere, which corresponded quite accurately to real processes. The practically developed traditional ideas about methods of waste disposal have historically been joined by qualitatively different approaches developed with the discovery of microorganisms, forming not only empirically, but also scientifically grounded methodological support for the safety of humans and their habitat. In medicine and social management systems, corresponding sub-sectors were formed, for example, sanitary and epidemiological affairs, municipal hygiene, etc.

With the rapid development of chemistry and chemical production, new, previously unknown elements and chemical compounds, including those that do not exist in nature, appeared in industrial and household waste in massive quantities. In scale, this phenomenon has become comparable to natural geochemical processes. Humanity has found itself faced with the need to reach another level of problem assessment, where, for example, accumulative and delayed effects, methods for identifying exposure dosages, the need to use new methods and special highly sensitive equipment for detecting danger, etc. must be taken into account.

A qualitatively different danger, although similar to the chemical one in some of its characteristics, was brought to humans by "radioactivity" , as a phenomenon that is not directly perceived by human senses, is not destroyed by methods known to mankind, and is still generally insufficiently studied: the discovery of new properties, impacts and consequences of this phenomenon cannot be ruled out. Therefore, when forming general and specific scientific and practical tasks “to eliminate the danger of radioactive waste” and, in particular, when solving these problems, constant difficulties arise, showing that the traditional formulation does not accurately reflect the real, objective nature of the “radwaste problem”. However, the ideology of such a statement is widespread in legal and non-legal documents of a national and interstate nature, which, as can be assumed, cover a wide range of modern scientific views, directions, research and practical activities; take into account the developments of all well-known domestic and foreign organizations dealing with the “radwaste problem”.

Decree of the Government of the Russian Federation dated October 23, 1995 No. 1030 approved the Federal Target Program “Management of Radioactive Waste and Spent Nuclear Materials, Their Recycling and Disposal for 1996-2005.”

Radioactive waste is considered in it “as substances (in any state of aggregation), materials, products, equipment, objects of biological origin that are not subject to further use, in which the content of radionuclides exceeds the levels established by regulations. The Program has a special section “State of the Problem”, containing a description of specific objects and public areas where “radioactive waste management” occurs, as well as general quantitative characteristics of the “radwaste problem” in Russia.

“The large amount of accumulated unconditioned radioactive waste, the insufficiency of technical means to ensure the safe handling of this waste and spent nuclear fuel, the lack of reliable storage facilities for their long-term storage and (or) disposal increase the risk of radiation accidents and create a real threat of radioactive contamination of the environment and over-irradiation population and personnel of organizations and enterprises whose activities are related to the use of atomic energy and radioactive materials.”

The main sources of high-level radioactive waste (RAW) are nuclear energy (spent nuclear fuel) and military programs (plutonium from nuclear warheads, spent fuel from transport reactors of nuclear submarines, liquid waste from radiochemical plants, etc.).

The question arises: should radioactive waste be considered simply as waste or as a potential source of energy? The answer to this question determines whether we want to store them (in an accessible form) or bury them (that is, make them inaccessible). The generally accepted answer now is that radioactive waste is indeed waste, with the possible exception of plutonium. Plutonium can theoretically serve as a source of energy, although the technology for generating energy from it is complex and quite dangerous. Many countries, including Russia and the United States, are now at a crossroads: to “launch” plutonium technology using plutonium released during disarmament, or bury this plutonium? Recently, the Russian government and Minatom announced that they want to reprocess weapons-grade plutonium together with the United States; this means the possibility of developing plutonium energy.

For 40 years, scientists have been comparing options for disposal of radioactive waste. The main idea is that they must be placed in such a place that they cannot enter the environment and harm humans. This ability to harm radioactive waste is retained for tens and hundreds of thousands of years. Irradiated nuclear fuel, which we extract from the reactor contains radioisotopes with half-lives from several hours to a million years (half-life is the time during which the amount of radioactive substance is halved, and in some cases new radioactive substances appear). But the overall radioactivity of waste decreases significantly over time. For radium, the half-life is 1620 years, and it is easy to calculate that after 10 thousand years about 1/50 of the original amount of radium will remain. The regulations of most countries provide for waste safety for a period of 10 thousand years. Of course, this does not mean that after this time, radioactive waste will no longer be dangerous: we are simply shifting further responsibility for radioactive waste to distant posterity. To do this, it is necessary that the places and form of burial of this waste be known to posterity. Note that the entire written history of mankind is less than 10 thousand years old. The challenges that arise during the disposal of radioactive waste are unprecedented in the history of technology: people have never set themselves such long-term goals.

An interesting aspect of the problem is that it is necessary not only to protect people from waste, but at the same time to protect waste from people. During the period allotted for their burial, many socio-economic formations will change. It cannot be ruled out that in a certain situation, radioactive waste may become a desirable target for terrorists, targets for attack in a military conflict and so on. It is clear that, thinking about millennia, we cannot rely on, say, government control and protection - it is impossible to foresee what changes may occur. It may be best to make the waste physically inaccessible to humans, although on the other hand this would make it difficult for our descendants to take further security measures.

It is clear that not a single technical solution, not a single artificial material can “work” for thousands of years. The obvious conclusion is that the natural environment itself must isolate waste. Options were considered: burying radioactive waste in deep oceanic depressions, in bottom sediments of the oceans, in polar caps; send them to space; put them in deep layers of the earth's crust. It is now generally accepted that the optimal way is to bury waste in deep geological formations.

It is clear that solid radioactive waste is less prone to penetration into the environment (migration) than liquid radioactive waste. Therefore, it is assumed that liquid radioactive waste will first be converted into solid form (vitrified, converted into ceramics, etc.). However, in Russia, injection of liquid highly active radioactive waste into deep underground horizons is still practiced (Krasnoyarsk, Tomsk, Dimitrovgrad).

Currently, the so-called "multi-barrier" or “deeply echeloned” burial concept. The waste is first contained by a matrix (glass, ceramics, fuel pellets), then a multi-purpose container (used for transport and disposal), then a sorbent fill around the containers, and finally by the geological environment.

So, we will try to bury radioactive waste in deep geological fractions. At the same time, we were given a condition: to show that our burial will work, as we plan, for 10 thousand years. Let's now see what problems we will encounter along this path.

The first problems arise at the stage of selecting sites for study.

In the USA, for example, not a single state wants it. So that a national burial site is located on its territory. This led to the fact that, through the efforts of politicians, many potentially suitable areas were crossed off the list, not on the basis of a scientific approach, but as a result of political games.

What does it look like in Russia? Currently, in Russia it is still possible to study areas without feeling significant pressure from local authorities (if you do not involve burial near cities!). I believe that as the real independence of the regions and subjects of the Federation increases, the situation will shift towards the situation of the United States. There is already a sense of Minatom’s inclination to shift its activities to military sites over which there is practically no control: for example, the Novaya Zemlya archipelago (Russian test site No. 1) is supposed to be used for the creation of a burial site, although in terms of geological parameters this is far from the best place, which will be discussed later .

But let’s assume that the first stage is over and the site has been selected. It is necessary to study it and give a forecast for the functioning of the burial for 10 thousand years. Here a new problem appears.

Lack of development of the method.

Geology is a descriptive science. Certain branches of geology deal with predictions (for example, engineering geology predicts the behavior of soils during construction, etc.), but never before has geology been tasked with predicting the behavior of geological systems for tens of thousands of years. From many years of research in different countries, doubts even arose whether a more or less reliable forecast for such periods is even possible.

Let us imagine, however, that we managed to develop a reasonable plan for studying the site. It is clear that it will take many years to implement this plan: for example, Mount Yaka in Nevada has been studied for more than 15 years, but a conclusion about the suitability or unsuitability of this mountain will not be made earlier than in 5 years. At the same time, the disposal program will come under increasing pressure.

Pressure from external circumstances.

During the Cold War, waste was ignored; they accumulated, were stored in temporary containers, were lost, etc. An example is the Hanford military facility (analogous to our “Beacon”), where there are several hundred giant tanks with liquid waste, and for many of them it is not known what is inside. One sample costs 1 million dollars! There, in Hanford, buried and “forgotten” barrels or boxes of waste are discovered about once a month.

In general, over the years of development of nuclear technology, a lot of waste has accumulated. Temporary storage facilities at many nuclear power plants are close to filling, and at military complexes they are often on the verge of failure due to old age or even beyond this point.

So, the burial problem requires urgent solutions. Awareness of this urgency is becoming increasingly acute, especially since 430 power reactors, hundreds of research reactors, hundreds of transport reactors of nuclear submarines, cruisers and icebreakers continue to continuously accumulate radioactive waste. But people with their backs to the wall don't necessarily come up with the best technical solutions and are more likely to make mistakes. Meanwhile, in decisions related to nuclear technology, errors can be very costly.

Let's finally assume that we spent 10-20 billion dollars and 15-20 years studying a potential site. It's time to make a decision. Obviously, there are no ideal places on Earth, and any place will have positive and negative properties from the point of view of burial. Obviously, you will have to decide whether the positive properties outweigh the negative ones, and whether these positive properties provide sufficient security.

Decision making and technological complexity of the problem

The disposal problem is technically extremely complex. Therefore, it is very important to have, firstly, high-quality science, and secondly, effective interaction (as they say in America - “interface”) between science and decision-making politicians.

The Russian concept of underground isolation of radioactive waste and spent nuclear fuel in permafrost rocks was developed at the Institute of Industrial Technology of the Russian Ministry of Atomic Energy (VNIPIP). It was approved by the State Environmental Expertise of the Ministry of Ecology and Natural Resources of the Russian Federation, the Ministry of Health of the Russian Federation and Gosatomnadzor of the Russian Federation. Scientific support for the concept is provided by the Department of Permafrost Science at Moscow State University. It should be noted that this concept is unique. As far as I know, no country in the world is considering the issue of burying radioactive waste in permafrost.

The main idea is this. We place heat-generating waste in the permafrost and separate it from the rocks with an impenetrable engineered barrier. Due to heat release, the permafrost around the burial begins to thaw, but after some time, when the heat release decreases (due to the decay of short-lived isotopes), the rocks will freeze again. Therefore, it is enough to ensure the impermeability of engineering barriers for the period when the permafrost thaws; After freezing, migration of radionuclides becomes impossible.

Uncertainty concept

There are at least two serious problems with this concept.

First, the concept assumes that frozen rocks are impenetrable to radionuclides. At first glance, this seems reasonable: all water is frozen, ice is usually motionless and does not dissolve radionuclides. But if you carefully study the literature, it turns out that many chemical elements migrate quite actively in frozen rocks. Even at temperatures of 10-12ºC, non-freezing, so-called film, water is present in the rocks. What is especially important is that the properties of the radioactive elements that make up radioactive waste, from the point of view of their possible migration in permafrost, have not been studied at all. Therefore, the assumption that frozen rocks are impermeable to radionuclides is without any basis.

Secondly, even if it turns out that permafrost is indeed a good insulator of radioactive waste, it is impossible to prove that the permafrost itself will last long enough: let us recall that the standards provide for disposal for a period of 10 thousand years. It is known that the state of permafrost is determined by climate, with the two most important parameters being air temperature and the amount of precipitation. As you know, air temperatures are rising due to global climate change. The highest rate of warming occurs at the middle and high latitudes of the northern hemisphere. It is clear that such warming should lead to thawing of ice and reduction of permafrost.

Calculations show that active thawing can begin within 80-100 years, and the rate of thawing can reach 50 meters per century. Thus, the frozen rocks of Novaya Zemlya can completely disappear in 600-700 years, and this is only 6-7% of the time required to isolate the waste. Without permafrost Carbonate rocks of Novaya Zemlya have very low insulating properties with respect to radionuclides.

The problem of storage and disposal of radioactive waste (RAW) is the most important and unresolved problem of nuclear energy.

No one in the world yet knows where and how to store high-level radioactive waste, although work in this direction is underway. So far we are talking about promising, and by no means industrial technologies for enclosing highly active radioactive waste in refractory glass or ceramic compounds. However, it is unclear how these materials will behave under the influence of radioactive waste contained in them for millions of years. Such a long shelf life is due to the huge half-life of a number of radioactive elements. It is clear that their release to the outside is inevitable, because the material of the container in which they will be enclosed does not “live” that much.

All technologies for processing and storing radioactive waste are conditional and questionable. And if nuclear scientists, as usual, dispute this fact, then it would be appropriate to ask them: “Where is the guarantee that all existing storage facilities and burial grounds are not already carriers of radioactive contamination, since all observations of them are hidden from the public?”

There are several burial grounds in our country, although they try to keep silent about their existence. The largest is located in the Krasnoyarsk region near the Yenisei, where waste from most Russian nuclear power plants and nuclear waste from a number of European countries are buried. When carrying out scientific research work on this storage facility, the results turned out to be positive, but recently observations have shown a violation of the ecosystem of the Yenisei River, that mutant fish have appeared, and the structure of the water in certain areas has changed, although the data of scientific examinations is carefully hidden.

In the world, the disposal of high-level radioactive waste has not yet been carried out; there is only experience in their temporary storage.

Bibliography

1. Vershinin N.V. Sanitary and technical requirements for sealed radiation sources.

In the book. "Proceedings of the Symposium". M., Atomizdat, 1976

2. Frumkin M. L. et al. Technological foundations of radiation processing of food products. M., Food industry, 1973

3. Breger A. Kh. Radioactive isotopes – sources of radiation in radiation-chemical technology. Isotopes in the USSR, 1975, No. 44, pp. 23-29.

4. Pertsovsky E. S., Sakharov E. V. Radioisotope devices in the food, light and pulp and paper industries. M., Atomizdat, 1972

5. Vorobyov E.I., Pobedinsky M.N. Essays on the development of domestic radiation medicine. M., Medicine, 1972

6. Selection of a site for the construction of a radioactive waste storage facility. E.I.M., TsNIIatominform, 1985, No. 20.

7. Current state of the problem of radioactive waste disposal in the USA. Nuclear technology abroad, 1988, No. 9.

8. Heinonen Dis, Disera F. Disposal of nuclear waste: processes occurring in underground storage facilities: IAEA Bulletin, Vienna, 1985, vol. 27, no. 2.

9. Geological studies of sites for the final disposal of radioactive waste: E.I.M.: TsNIIatominform, 1987, No. 38.

10. Bryzgalova R.V., Rogozin Yu.M., Sinitsyna G.S. et al. Assessment of some radiochemical and geochemical factors that determine the localization of radionuclides during the burial of radioactive waste in geological formations. Proceedings of the 6th CMEA Symposium, vol. 2, 1985.

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Course work

On the topic: "Radioactivity. The use of radioactive isotopes in technology"

Introduction

1. Types of radioactive radiation

2.Other types of radioactivity

3. Alpha decay

4.Beta decay

5. Gamma decay

6.The law of radioactive decay

7.Radioactive series

9.Use of radioactive isotopes

Introduction

Radioactivity is the transformation of atomic nuclei into other nuclei, accompanied by the emission of various particles and electromagnetic radiation. Hence the name of the phenomenon: in Latin radio - radiate, activus - effective. This word was coined by Marie Curie. When an unstable nucleus - a radionuclide - decays, one or more high-energy particles fly out of it at high speed. The flow of these particles is called radioactive radiation or simply radiation.

X-rays. The discovery of radioactivity was directly related to the discovery of Roentgen. Moreover, for some time they thought that these were the same type of radiation. Late 19th century In general, he was rich in the discovery of various kinds of previously unknown “radiations.” In the 1880s, the English physicist Joseph John Thomson began studying elementary negative charge carriers; in 1891, the Irish physicist George Johnston Stoney (1826-1911) called these particles electrons. Finally, in December, Wilhelm Conrad Roentgen announced the discovery of a new type of ray, which he called X-rays. Until now, in most countries they are called that, but in Germany and Russia the proposal of the German biologist Rudolf Albert von Kölliker (1817-1905) to call the rays X-rays has been accepted. These rays are created when electrons flying quickly in a vacuum (cathode rays) collide with an obstacle. It was known that when cathode rays hit glass, it emits visible light - green luminescence. X-ray discovered that at the same time some other invisible rays were emanating from the green spot on the glass. This happened by accident: in a dark room, a nearby screen covered with barium tetracyanoplatinate Ba glowed, added 05/03/2014

Information about radioactive radiation. Interaction of alpha, beta and gamma particles with matter. The structure of the atomic nucleus. The concept of radioactive decay. Features of the interaction of neutrons with matter. Quality factor for various types of radiation.

abstract, added 01/30/2010

Structure of matter, types of nuclear decay: alpha decay, beta decay. Laws of radioactivity, interaction of nuclear radiation with matter, biological effects of ionizing radiation. Radiation background, quantitative characteristics of radioactivity.

abstract, added 04/02/2012

Nuclear physical properties and radioactivity of heavy elements. Alpha and beta transformations. The essence of gamma radiation. Radioactive transformation. Spectra of scattered gamma radiation from media with different serial numbers. Physics of nuclear magnetic resonance.

presentation, added 10/15/2013

Nuclear ionizing radiation, its sources and biological effects on organs and tissues of a living organism. Characteristics of morphological changes at the systemic and cellular levels. Classification of the consequences of human exposure, radioprotective agents.

presentation, added 11/24/2014

Works by Ernest Rutherford. Planetary model of the atom. Discovery of alpha and beta radiation, the short-lived isotope of radon and the formation of new chemical elements during the decay of heavy chemical radioactive elements. Effect of radiation on tumors.

presentation, added 05/18/2011

X-rays are electromagnetic waves whose spectrum lies between ultraviolet and gamma radiation. History of discovery; laboratory sources: X-ray tubes, particle accelerators. Interaction with the substance, biological effects.

presentation, added 02/26/2012

Concept and classification of radioactive elements. Basic information about the atom. Characteristics of types of radioactive radiation, its penetrating ability. Half-lives of some radionuclides. Scheme of the process of neutron-induced nuclear fission.

presentation, added 02/10/2014

Gamma radiation is short-wave electromagnetic radiation. On the scale of electromagnetic waves, it borders on hard X-ray radiation, occupying the region of higher frequencies. Gamma radiation has an extremely short wavelength.

abstract, added 11/07/2003

Characteristics of corpuscular, photon, proton, x-ray types of radiation. Features of the interaction of alpha, beta, gamma particles with an ionizing substance. The essence of Compton scattering and the effect of electron-positron pair formation.