X-ray radiation. Characteristic X-ray radiation: description, action, features

X-RAY RADIATION
invisible radiation capable of penetrating, albeit to varying degrees, all substances. It is electromagnetic radiation with a wavelength of about 10-8 cm. Like visible light, X-rays cause blackening of photographic film. This property is of great importance for medicine, industry and scientific research. Passing through the object under study and then falling on the film, X-ray radiation depicts its internal structure on it. Since the penetrating power of X-ray radiation is different for different materials, parts of the object that are less transparent to it give brighter areas in the photograph than those through which the radiation penetrates well. Thus, bone tissues are less transparent to x-rays than the tissues that make up the skin and internal organs. Therefore, on the radiograph, the bones will be indicated as lighter areas and the fracture site, which is more transparent for radiation, can be quite easily detected. X-ray imaging is also used in dentistry to detect caries and abscesses in the roots of teeth, as well as in industry to detect cracks in castings, plastics and rubbers. X-rays are used in chemistry to analyze compounds and in physics to study the structure of crystals. An X-ray beam passing through a chemical compound causes a characteristic secondary radiation, the spectroscopic analysis of which allows the chemist to determine the composition of the compound. When falling on a crystalline substance, an X-ray beam is scattered by the atoms of the crystal, giving a clear, regular pattern of spots and stripes on a photographic plate, which makes it possible to establish the internal structure of the crystal. The use of X-rays in cancer treatment is based on the fact that it kills cancer cells. However, it can also have an undesirable effect on normal cells. Therefore, extreme caution must be exercised in this use of X-rays. X-ray radiation was discovered by the German physicist W. Roentgen (1845-1923). His name is immortalized in some other physical terms associated with this radiation: the international unit of the dose of ionizing radiation is called the roentgen; a picture taken with an x-ray machine is called a radiograph; The field of radiological medicine that uses x-rays to diagnose and treat diseases is called radiology. Roentgen discovered radiation in 1895 while a professor of physics at the University of Würzburg. While conducting experiments with cathode rays (electron flows in discharge tubes), he noticed that a screen located near the vacuum tube, covered with crystalline barium cyanoplatinite, glows brightly, although the tube itself is covered with black cardboard. Roentgen further established that the penetrating power of the unknown rays he discovered, which he called X-rays, depended on the composition of the absorbing material. He also imaged the bones of his own hand by placing it between a cathode ray discharge tube and a screen coated with barium cyanoplatinite. Roentgen's discovery was followed by experiments by other researchers who discovered many new properties and possibilities for using this radiation. A great contribution was made by M. Laue, W. Friedrich and P. Knipping, who demonstrated in 1912 the diffraction of X-rays when it passes through a crystal; W. Coolidge, who in 1913 invented a high-vacuum X-ray tube with a heated cathode; G. Moseley, who established in 1913 the relationship between the wavelength of radiation and the atomic number of an element; G. and L. Braggi, who received the Nobel Prize in 1915 for developing the fundamentals of X-ray diffraction analysis.
OBTAINING X-RAY RADIATION
X-ray radiation occurs when electrons moving at high speeds interact with matter. When electrons collide with atoms of any substance, they quickly lose their kinetic energy. In this case, most of it is converted into heat, and a small fraction, usually less than 1%, is converted into X-ray energy. This energy is released in the form of quanta - particles called photons that have energy but have zero rest mass. X-ray photons differ in their energy, which is inversely proportional to their wavelength. With the conventional method of obtaining x-rays, a wide range of wavelengths is obtained, which is called the x-ray spectrum. The spectrum contains pronounced components, as shown in Fig. 1. A wide "continuum" is called a continuous spectrum or white radiation. The sharp peaks superimposed on it are called characteristic x-ray emission lines. Although the entire spectrum is the result of collisions of electrons with matter, the mechanisms for the appearance of its wide part and lines are different. A substance consists of a large number of atoms, each of which has a nucleus surrounded by electron shells, and each electron in the shell of an atom of a given element occupies a certain discrete energy level. Usually these shells, or energy levels, are denoted by the symbols K, L, M, etc., starting from the shell closest to the nucleus. When an incident electron of sufficiently high energy collides with one of the electrons bound to the atom, it knocks that electron out of its shell. The empty space is occupied by another electron from the shell, which corresponds to a higher energy. This latter gives off excess energy by emitting an X-ray photon. Since the shell electrons have discrete energy values, the resulting X-ray photons also have a discrete spectrum. This corresponds to sharp peaks for certain wavelengths, the specific values of which depend on the target element. The characteristic lines form K-, L- and M-series, depending on which shell (K, L or M) the electron was removed from. The relationship between the wavelength of X-rays and the atomic number is called Moseley's law (Fig. 2).

If an electron collides with a relatively heavy nucleus, then it slows down, and its kinetic energy is released in the form of an X-ray photon of approximately the same energy. If he flies past the nucleus, he will lose only part of his energy, and the rest will be transferred to other atoms that fall in his way. Each act of energy loss leads to the emission of a photon with some energy. A continuous x-ray spectrum appears, the upper limit of which corresponds to the energy of the fastest electron. This is the mechanism for the formation of a continuous spectrum, and the maximum energy (or minimum wavelength) that fixes the boundary of the continuous spectrum is proportional to the accelerating voltage, which determines the speed of the incident electrons. The spectral lines characterize the material of the bombarded target, while the continuous spectrum is determined by the energy of the electron beam and practically does not depend on the target material. X-rays can be obtained not only by electron bombardment, but also by irradiating the target with X-rays from another source. In this case, however, most of the energy of the incident beam goes into the characteristic X-ray spectrum, and a very small fraction of it falls into the continuous spectrum. Obviously, the incident X-ray beam must contain photons whose energy is sufficient to excite the characteristic lines of the bombarded element. The high percentage of energy per characteristic spectrum makes this method of X-ray excitation convenient for scientific research.
X-ray tubes. In order to obtain X-ray radiation due to the interaction of electrons with matter, it is necessary to have a source of electrons, means of accelerating them to high speeds, and a target capable of withstanding electron bombardment and producing X-ray radiation of the required intensity. The device that has all this is called an x-ray tube. Early explorers used "deep vacuum" tubes such as today's discharge tubes. The vacuum in them was not very high. Discharge tubes contain a small amount of gas, and when a large potential difference is applied to the electrodes of the tube, the gas atoms turn into positive and negative ions. The positive ones move towards the negative electrode (cathode) and, falling on it, knock electrons out of it, and they, in turn, move towards the positive electrode (anode) and, bombarding it, create a stream of X-ray photons. In the modern X-ray tube developed by Coolidge (Fig. 3), the source of electrons is a tungsten cathode heated to a high temperature. The electrons are accelerated to high speeds by the high potential difference between the anode (or anticathode) and the cathode. Since the electrons must reach the anode without colliding with atoms, a very high vacuum is required, for which the tube must be well evacuated. This also reduces the probability of ionization of the remaining gas atoms and the associated side currents.

The electrons are focused on the anode by a specially shaped electrode surrounding the cathode. This electrode is called the focusing electrode and together with the cathode forms the "electronic searchlight" of the tube. The anode subjected to electron bombardment must be made of a refractory material, since most of the kinetic energy of the bombarding electrons is converted into heat. In addition, it is desirable that the anode be made of a material with a high atomic number, since the x-ray yield increases with increasing atomic number. Tungsten, whose atomic number is 74, is most often chosen as the anode material. The design of X-ray tubes can be different depending on the application conditions and requirements.
X-RAY DETECTION
All methods for detecting X-rays are based on their interaction with matter. Detectors can be of two types: those that give an image, and those that do not. The former include X-ray fluorography and fluoroscopy devices, in which the X-ray beam passes through the object under study, and the transmitted radiation enters the luminescent screen or film. The image appears due to the fact that different parts of the object under study absorb radiation in different ways - depending on the thickness of the substance and its composition. In detectors with a luminescent screen, the X-ray energy is converted into a directly observable image, while in radiography it is recorded on a sensitive emulsion and can only be observed after the film has been developed. The second type of detectors includes a wide variety of devices in which the X-ray energy is converted into electrical signals that characterize the relative intensity of the radiation. These include ionization chambers, a Geiger counter, a proportional counter, a scintillation counter, and some special detectors based on cadmium sulfide and selenide. Currently, scintillation counters can be considered the most efficient detectors, which work well in a wide energy range.
see also PARTICLE DETECTORS . The detector is selected taking into account the conditions of the problem. For example, if it is necessary to accurately measure the intensity of diffracted X-ray radiation, then counters are used that allow measurements to be made with an accuracy of fractions of a percent. If it is necessary to register a lot of diffracted beams, then it is advisable to use X-ray film, although in this case it is impossible to determine the intensity with the same accuracy.
X-RAY AND GAMMA DEFECTOSCOPY
One of the most common applications of X-rays in industry is material quality control and flaw detection. The x-ray method is non-destructive, so that the material being tested, if found to meet the required requirements, can then be used for its intended purpose. Both x-ray and gamma flaw detection are based on the penetrating power of x-rays and the characteristics of its absorption in materials. Penetrating power is determined by the energy of X-ray photons, which depends on the accelerating voltage in the X-ray tube. Therefore, thick samples and samples from heavy metals, such as gold and uranium, require an X-ray source with a higher voltage for their study, and for thin samples, a source with a lower voltage is sufficient. For gamma-ray flaw detection of very large castings and large rolled products, betatrons and linear accelerators are used, accelerating particles to energies of 25 MeV and more. The absorption of X-rays in a material depends on the thickness of the absorber d and the absorption coefficient m and is determined by the formula I = I0e-md, where I is the intensity of the radiation transmitted through the absorber, I0 is the intensity of the incident radiation, and e = 2.718 is the base of natural logarithms. For a given material, at a given wavelength (or energy) of X-rays, the absorption coefficient is a constant. But the radiation of an X-ray source is not monochromatic, but contains a wide spectrum of wavelengths, as a result of which the absorption at the same thickness of the absorber depends on the wavelength (frequency) of the radiation. X-ray radiation is widely used in all industries associated with the processing of metals by pressure. It is also used to test artillery barrels, foodstuffs, plastics, to test complex devices and systems in electronic engineering. (Neutronography, which uses neutron beams instead of X-rays, is used for similar purposes.) X-rays are also used for other purposes, such as examining paintings to determine their authenticity or detecting additional layers of paint on top of the main layer.
X-RAY DIFFRACTION
X-ray diffraction provides important information about solids—their atomic structure and crystal form—as well as about liquids, amorphous bodies, and large molecules. The diffraction method is also used for accurate (with an error of less than 10-5) determination of interatomic distances, detection of stresses and defects, and for determining the orientation of single crystals. The diffraction pattern can identify unknown materials, as well as detect the presence of impurities in the sample and determine them. The importance of the X-ray diffraction method for the progress of modern physics can hardly be overestimated, since the modern understanding of the properties of matter is ultimately based on data on the arrangement of atoms in various chemical compounds, on the nature of the bonds between them, and on structural defects. The main tool for obtaining this information is the X-ray diffraction method. X-ray diffraction crystallography is essential for determining the structures of complex large molecules, such as those of deoxyribonucleic acid (DNA), the genetic material of living organisms. Immediately after the discovery of X-ray radiation, scientific and medical interest was concentrated both on the ability of this radiation to penetrate through bodies, and on its nature. Experiments on the diffraction of X-rays on slits and diffraction gratings showed that it belongs to electromagnetic radiation and has a wavelength of the order of 10-8-10-9 cm. Even earlier, scientists, in particular W. Barlow, guessed that the regular and symmetrical shape of natural crystals is due to the ordered arrangement of atoms that form the crystal. In some cases, Barlow was able to correctly predict the structure of a crystal. The value of the predicted interatomic distances was 10-8 cm. The fact that the interatomic distances turned out to be of the order of the X-ray wavelength made it possible in principle to observe their diffraction. The result was the idea for one of the most important experiments in the history of physics. M. Laue organized an experimental test of this idea, which was carried out by his colleagues W. Friedrich and P. Knipping. In 1912, the three of them published their work on the results of X-ray diffraction. Principles of X-ray diffraction. To understand the phenomenon of X-ray diffraction, one must consider in order: firstly, the spectrum of X-rays, secondly, the nature of the crystal structure and, thirdly, the phenomenon of diffraction itself. As mentioned above, the characteristic X-ray radiation consists of a series of spectral lines of a high degree of monochromaticity, determined by the anode material. With the help of filters, you can select the most intense of them. Therefore, by choosing the anode material in an appropriate way, it is possible to obtain a source of almost monochromatic radiation with a very precisely defined wavelength value. The wavelengths of the characteristic radiation typically range from 2.285 for chromium to 0.558 for silver (the values for the various elements are known to six significant figures). The characteristic spectrum is superimposed on a continuous "white" spectrum of much lower intensity, due to the deceleration of the incident electrons in the anode. Thus, two types of radiation can be obtained from each anode: characteristic and bremsstrahlung, each of which plays an important role in its own way. Atoms in the crystal structure are located at regular intervals, forming a sequence of identical cells - a spatial lattice. Some lattices (for example, for most ordinary metals) are quite simple, while others (for example, for protein molecules) are quite complex. The crystal structure is characterized by the following: if one shifts from some given point of one cell to the corresponding point of the neighboring cell, then exactly the same atomic environment will be found. And if some atom is located at one or another point of one cell, then the same atom will be located at the equivalent point of any neighboring cell. This principle is strictly valid for a perfect, ideally ordered crystal. However, many crystals (for example, metallic solid solutions) are disordered to some extent; crystallographically equivalent places can be occupied by different atoms. In these cases, it is not the position of each atom that is determined, but only the position of an atom "statistically averaged" over a large number of particles (or cells). The phenomenon of diffraction is discussed in the article OPTICS and the reader may refer to this article before moving on. It shows that if waves (for example, sound, light, X-rays) pass through a small slit or hole, then the latter can be considered as a secondary source of waves, and the image of the slit or hole consists of alternating light and dark stripes. Further, if there is a periodic structure of holes or slots, then as a result of the amplifying and attenuating interference of rays coming from different holes, a clear diffraction pattern arises. X-ray diffraction is a collective scattering phenomenon in which the role of holes and scattering centers is played by periodically arranged atoms of the crystal structure. Mutual amplification of their images at certain angles gives a diffraction pattern similar to that which would result from the diffraction of light on a three-dimensional diffraction grating. Scattering occurs due to the interaction of the incident X-ray radiation with electrons in the crystal. Due to the fact that the wavelength of X-ray radiation is of the same order as the dimensions of the atom, the wavelength of the scattered X-ray radiation is the same as that of the incident. This process is the result of forced oscillations of electrons under the action of incident X-rays. Consider now an atom with a cloud of bound electrons (surrounding the nucleus) on which X-rays are incident. Electrons in all directions simultaneously scatter the incident and emit their own X-ray radiation of the same wavelength, although of different intensity. The intensity of the scattered radiation is related to the atomic number of the element, since the atomic number is equal to the number of orbital electrons that can participate in scattering. (This dependence of the intensity on the atomic number of the scattering element and on the direction in which the intensity is measured is characterized by the atomic scattering factor, which plays an extremely important role in the analysis of the structure of crystals.) Let us choose in the crystal structure a linear chain of atoms located at the same distance from each other, and consider their diffraction pattern. It has already been noted that the X-ray spectrum consists of a continuous part ("continuum") and a set of more intense lines characteristic of the element that is the anode material. Let's say we filtered out the continuous spectrum and got an almost monochromatic X-ray beam directed at our linear chain of atoms. The amplification condition (amplifying interference) is satisfied if the difference between the paths of waves scattered by neighboring atoms is a multiple of the wavelength. If the beam is incident at an angle a0 to a line of atoms separated by intervals a (period), then for the diffraction angle a the path difference corresponding to the gain will be written as a(cos a - cosa0) = hl, where l is the wavelength and h is integer (Fig. 4 and 5).

To extend this approach to a three-dimensional crystal, it is only necessary to choose rows of atoms in two other directions in the crystal and solve the three equations thus obtained jointly for three crystal axes with periods a, b and c. The other two equations are

These are the three fundamental Laue equations for X-ray diffraction, with the numbers h, k and c being the Miller indices for the diffraction plane.
see also CRYSTALS AND CRYSTALLOGRAPHY. Considering any of the Laue equations, for example the first one, one can notice that since a, a0, l are constants, and h = 0, 1, 2, ..., its solution can be represented as a set of cones with a common axis a (Fig. . 5). The same is true for directions b and c. In the general case of three-dimensional scattering (diffraction), the three Laue equations must have a common solution, i.e. three diffraction cones located on each of the axes must intersect; the common line of intersection is shown in fig. 6. The joint solution of the equations leads to the Bragg-Wulf law:

l = 2(d/n)sinq, where d is the distance between the planes with indices h, k and c (period), n = 1, 2, ... are integers (diffraction order), and q is the angle formed by incident beam (as well as diffracting) with the plane of the crystal in which diffraction occurs. Analyzing the equation of the Bragg - Wolfe law for a single crystal located in the path of a monochromatic X-ray beam, we can conclude that diffraction is not easy to observe, because l and q are fixed, and sinq DIFFRACTION ANALYSIS METHODS
Laue method. The Laue method uses a continuous "white" spectrum of X-rays, which is directed to a stationary single crystal. For a specific value of the period d, the wavelength corresponding to the Bragg-Wulf condition is automatically selected from the entire spectrum. The Laue patterns obtained in this way make it possible to judge the directions of the diffracted beams and, consequently, the orientations of the crystal planes, which also makes it possible to draw important conclusions about the symmetry, orientation of the crystal, and the presence of defects in it. In this case, however, information about the spatial period d is lost. On fig. 7 shows an example of a Lauegram. The X-ray film was located on the side of the crystal opposite to that on which the X-ray beam was incident from the source.

Debye-Scherrer method (for polycrystalline samples). Unlike the previous method, monochromatic radiation (l = const) is used here, and the angle q is varied. This is achieved by using a polycrystalline sample consisting of numerous small crystallites of random orientation, among which there are those that satisfy the Bragg-Wulf condition. The diffracted beams form cones, the axis of which is directed along the X-ray beam. For imaging, a narrow strip of X-ray film in a cylindrical cassette is usually used, and X-rays are propagated along the diameter through holes in the film. The debyegram obtained in this way (Fig. 8) contains exact information about the period d, i.e. about the structure of the crystal, but does not give the information that the Lauegram contains. Therefore, both methods complement each other. Let us consider some applications of the Debye-Scherrer method.

Identification of chemical elements and compounds. From the angle q determined from the Debyegram, one can calculate the interplanar distance d characteristic of a given element or compound. At present, many tables of d values have been compiled, which make it possible to identify not only one or another chemical element or compound, but also various phase states of the same substance, which does not always give a chemical analysis. It is also possible to determine the content of the second component in substitutional alloys with high accuracy from the dependence of the period d on the concentration.
Stress analysis. Based on the measured difference in interplanar distances for different directions in crystals, knowing the elastic modulus of the material, it is possible to calculate with high accuracy small stresses in it.
Studies of preferential orientation in crystals. If small crystallites in a polycrystalline sample are not completely randomly oriented, then the rings on the Debyegram will have different intensities. In the presence of a pronounced preferred orientation, the intensity maxima are concentrated in individual spots in the image, which becomes similar to the image for a single crystal. For example, during deep cold rolling, a metal sheet acquires a texture - a pronounced orientation of crystallites. According to the debaygram, one can judge the nature of the cold working of the material.
Study of grain sizes. If the grain size of the polycrystal is more than 10-3 cm, then the lines on the Debyegram will consist of separate spots, since in this case the number of crystallites is not enough to cover the entire range of values of the angles q. If the crystallite size is less than 10-5 cm, then the diffraction lines become wider. Their width is inversely proportional to the size of the crystallites. Broadening occurs for the same reason that a decrease in the number of slits reduces the resolution of a diffraction grating. X-ray radiation makes it possible to determine grain sizes in the range of 10-7-10-6 cm.
Methods for single crystals. In order for diffraction by a crystal to provide information not only about the spatial period, but also about the orientation of each set of diffracting planes, methods of a rotating single crystal are used. A monochromatic X-ray beam is incident on the crystal. The crystal rotates around the main axis, for which the Laue equations are satisfied. In this case, the angle q, which is included in the Bragg-Wulf formula, changes. The diffraction maxima are located at the intersection of the Laue diffraction cones with the cylindrical surface of the film (Fig. 9). The result is a diffraction pattern of the type shown in Fig. 10. However, complications are possible due to the overlap of different diffraction orders at one point. The method can be significantly improved if, simultaneously with the rotation of the crystal, the film is also moved in a certain way.

Studies of liquids and gases. It is known that liquids, gases and amorphous bodies do not have the correct crystal structure. But here, too, there is a chemical bond between the atoms in the molecules, due to which the distance between them remains almost constant, although the molecules themselves are randomly oriented in space. Such materials also give a diffraction pattern with a relatively small number of smeared maxima. The processing of such a picture by modern methods makes it possible to obtain information about the structure of even such non-crystalline materials.
SPECTROCHEMICAL X-RAY ANALYSIS
A few years after the discovery of X-rays, Ch. Barkla (1877-1944) discovered that when a high-energy X-ray flux acts on a substance, secondary fluorescent X-ray radiation is generated, which is characteristic of the element under study. Shortly thereafter, G. Moseley, in a series of his experiments, measured the wavelengths of the primary characteristic X-ray radiation obtained by electron bombardment of various elements, and deduced the relationship between the wavelength and the atomic number. These experiments, and Bragg's invention of the X-ray spectrometer, laid the foundation for spectrochemical X-ray analysis. The possibilities of X-rays for chemical analysis were immediately recognized. Spectrographs were created with registration on a photographic plate, in which the sample under study served as the anode of an X-ray tube. Unfortunately, this technique turned out to be very laborious, and therefore was used only when the usual methods of chemical analysis were inapplicable. An outstanding example of innovative research in the field of analytical X-ray spectroscopy was the discovery in 1923 by G. Hevesy and D. Coster of a new element, hafnium. The development of high-power X-ray tubes for radiography and sensitive detectors for radiochemical measurements during World War II largely contributed to the rapid growth of X-ray spectrography in the following years. This method has become widespread due to the speed, convenience, non-destructive nature of the analysis and the possibility of full or partial automation. It is applicable in the problems of quantitative and qualitative analysis of all elements with an atomic number greater than 11 (sodium). And although X-ray spectrochemical analysis is usually used to determine the critical components in a sample (from 0.1-100%), in some cases it is suitable for concentrations of 0.005% and even lower.
X-ray spectrometer. A modern X-ray spectrometer consists of three main systems (Fig. 11): excitation systems, i.e. x-ray tube with an anode made of tungsten or other refractory material and a power supply; analysis systems, i.e. an analyzer crystal with two multi-slit collimators, as well as a spectrogoniometer for fine adjustment; and registration systems with a Geiger or proportional or scintillation counter, as well as a rectifier, amplifier, counters and a chart recorder or other recording device.

X-ray fluorescent analysis. The analyzed sample is located in the path of the exciting x-rays. The region of the sample to be examined is usually isolated by a mask with a hole of the desired diameter, and the radiation passes through a collimator that forms a parallel beam. Behind the analyzer crystal, a slit collimator emits diffracted radiation for the detector. Usually, the maximum angle q is limited to 80–85°, so that only X-rays whose wavelength l is related to the interplanar distance d by the inequality l can diffract on the analyzer crystal. X-ray microanalysis. The flat analyzer crystal spectrometer described above can be adapted for microanalysis. This is achieved by constricting either the primary x-ray beam or the secondary beam emitted by the sample. However, a decrease in the effective size of the sample or the radiation aperture leads to a decrease in the intensity of the recorded diffracted radiation. An improvement to this method can be achieved by using a curved crystal spectrometer, which makes it possible to register a cone of divergent radiation, and not only radiation parallel to the axis of the collimator. With such a spectrometer, particles smaller than 25 µm can be identified. An even greater reduction in the size of the analyzed sample is achieved in the X-ray electron probe microanalyzer invented by R. Kasten. Here, a highly focused electron beam excites the characteristic X-ray emission of the sample, which is then analyzed by a bent-crystal spectrometer. Using such a device, it is possible to detect amounts of a substance of the order of 10–14 g in a sample with a diameter of 1 μm. Installations with electron beam scanning of the sample have also been developed, with the help of which it is possible to obtain a two-dimensional pattern of the distribution over the sample of the element whose characteristic radiation is tuned to the spectrometer.
MEDICAL X-RAY DIAGNOSIS
The development of x-ray technology has significantly reduced the exposure time and improved the quality of images, allowing even soft tissues to be studied.
Fluorography. This diagnostic method consists in photographing a shadow image from a translucent screen. The patient is placed between an x-ray source and a flat screen of phosphor (usually cesium iodide), which glows when exposed to x-rays. Biological tissues of varying degrees of density create shadows of X-ray radiation with varying degrees of intensity. A radiologist examines a shadow image on a fluorescent screen and makes a diagnosis. In the past, a radiologist relied on vision to analyze an image. Now there are various systems that amplify the image, display it on a television screen or record data in the computer's memory.
Radiography. The recording of an x-ray image directly on photographic film is called radiography. In this case, the organ under study is located between the X-ray source and the film, which captures information about the state of the organ at a given time. Repeated radiography makes it possible to judge its further evolution. Radiography allows you to very accurately examine the integrity of bone tissue, which consists mainly of calcium and is opaque to x-rays, as well as muscle tissue ruptures. With its help, better than a stethoscope or listening, the condition of the lungs is analyzed in case of inflammation, tuberculosis, or the presence of fluid. With the help of radiography, the size and shape of the heart, as well as the dynamics of its changes in patients suffering from heart disease, are determined.
contrast agents. Parts of the body and cavities of individual organs that are transparent to X-ray radiation become visible if they are filled with a contrast agent that is harmless to the body, but allows one to visualize the shape of internal organs and check their functioning. The patient either takes contrast agents orally (such as barium salts in the study of the gastrointestinal tract), or they are administered intravenously (such as iodine-containing solutions in the study of the kidneys and urinary tract). AT last years However, these methods are being replaced by diagnostic methods based on the use of radioactive atoms and ultrasound.
CT scan. In the 1970s, a new method of X-ray diagnostics was developed, based on a complete photograph of the body or its parts. Images of thin layers ("slices") are processed by a computer, and the final image is displayed on the monitor screen. This method is called computed x-ray tomography. It is widely used in modern medicine for diagnosing infiltrates, tumors and other brain disorders, as well as for diagnosing diseases of soft tissues inside the body. This technique does not require the introduction of foreign contrast agents and is therefore faster and more effective than traditional techniques.
BIOLOGICAL ACTION OF X-RAY RADIATION
The harmful biological effect of X-ray radiation was discovered shortly after its discovery by Roentgen. It turned out that the new radiation can cause something like a severe sunburn (erythema), accompanied, however, by deeper and more permanent damage to the skin. Appearing ulcers often turned into cancer. In many cases, fingers or hands had to be amputated. There were also deaths. It has been found that skin lesions can be avoided by reducing exposure time and dose, using shielding (eg lead) and remote controls. But gradually other, more long-term effects of X-ray exposure were revealed, which were then confirmed and studied in experimental animals. The effects due to the action of X-rays, as well as other ionizing radiations (such as gamma radiation emitted by radioactive materials) include: 1) temporary changes in the composition of the blood after a relatively small excess exposure; 2) irreversible changes in the composition of the blood (hemolytic anemia) after prolonged excessive exposure; 3) an increase in the incidence of cancer (including leukemia); 4) faster aging and early death; 5) the occurrence of cataracts. In addition, biological experiments on mice, rabbits and flies (Drosophila) have shown that even small doses of systematic irradiation of large populations, due to an increase in the rate of mutation, lead to harmful genetic effects. Most geneticists recognize the applicability of these data to the human body. As for the biological effect of X-ray radiation on the human body, it is determined by the level of the radiation dose, as well as by which particular organ of the body was exposed to radiation. For example, blood diseases are caused by irradiation of the hematopoietic organs, mainly the bone marrow, and genetic consequences - by irradiation of the genital organs, which can also lead to sterility. The accumulation of knowledge about the effects of X-ray radiation on the human body has led to the development of national and international standards for permissible radiation doses, published in various reference publications. In addition to X-rays, which are purposefully used by humans, there is also the so-called scattered, side radiation that occurs for various reasons, for example, due to scattering due to the imperfection of the lead protective screen, which does not completely absorb this radiation. In addition, many electrical devices that are not designed to produce X-rays nevertheless generate X-rays as a by-product. Such devices include electron microscopes, high-voltage rectifier lamps (kenotrons), as well as kinescopes of outdated color televisions. The production of modern color kinescopes in many countries is now under government control.
HAZARDOUS FACTORS OF X-RAY RADIATION
The types and degree of danger of X-ray exposure for people depend on the contingent of people exposed to radiation.
Professionals working with x-ray equipment. This category includes radiologists, dentists, as well as scientific and technical workers and personnel maintaining and using x-ray equipment. Effective measures are being taken to reduce the levels of radiation they have to deal with.
Patients. There are no strict criteria here, and the safe level of radiation that patients receive during treatment is determined by the attending physicians. Physicians are advised not to unnecessarily expose patients to x-rays. Particular caution should be exercised when examining pregnant women and children. In this case, special measures are taken.
Control methods. There are three aspects to this:
1) availability of adequate equipment, 2) enforcement of safety regulations, 3) proper use of equipment. In an x-ray examination, only the desired area should be exposed to radiation, be it dental examinations or lung examinations. Note that immediately after turning off the X-ray apparatus, both primary and secondary radiation disappear; there is also no residual radiation, which is not always known even to those who are directly connected with it in their work.
see also
ATOM STRUCTURE;

X-ray radiation plays a huge role in modern medicine; the history of the discovery of X-rays dates back to the 19th century.

X-rays are electromagnetic waves that are produced with the participation of electrons. With strong acceleration of charged particles, artificial x-rays are created. It passes through special equipment:

particle accelerators.

Discovery history

These rays were invented in 1895 by the German scientist Roentgen: while working with a cathode ray tube, he discovered the fluorescence effect of barium platinum cyanide. Then there was a description of such rays and their amazing ability to penetrate the tissues of the body. The rays began to be called x-rays (x-rays). Later in Russia they began to be called X-ray.

X-rays are able to penetrate even through walls. So Roentgen realized that he had made the greatest discovery in the field of medicine. It was from that time that separate sections in science began to form, such as radiology and radiology.

The rays are able to penetrate soft tissues, but are delayed, their length is determined by the obstacle of a hard surface. The soft tissues in the human body are the skin, and the hard tissues are the bones. In 1901, the scientist was awarded the Nobel Prize.

However, even before the discovery of Wilhelm Conrad Roentgen, other scientists were also interested in a similar topic. In 1853, the French physicist Antoine-Philiber Mason studied a high-voltage discharge between electrodes in a glass tube. The gas contained in it at low pressure began to emit a reddish glow. Pumping out excess gas from the tube led to the decay of the glow into a complex sequence of individual luminous layers, the hue of which depended on the amount of gas.

In 1878, William Crookes (English physicist) suggested that fluorescence occurs due to the impact of rays on the glass surface of the tube. But all these studies were not published anywhere, so Roentgen did not know about such discoveries. After the publication of his discoveries in 1895 in a scientific journal, where the scientist wrote that all bodies are transparent to these rays, albeit to a very different degree, other scientists became interested in similar experiments. They confirmed the invention of Roentgen, and further development and improvement of x-rays began.

Wilhelm Roentgen himself published two more scientific papers on the subject of x-rays in 1896 and 1897, after which he took up other activities. Thus, several scientists invented, but it was Roentgen who published scientific papers on this subject.

Imaging Principles

The features of this radiation are determined by the very nature of their appearance. Radiation occurs due to an electromagnetic wave. Its main properties include:

Reflection. If the wave hits the surface perpendicularly, it will not be reflected. In some situations, a diamond has the property of reflection.
The ability to penetrate tissue. In addition, the rays can pass through opaque surfaces of materials such as wood, paper, and the like.
absorbency. Absorption depends on the density of the material: the denser it is, the more X-rays absorb it.
Some substances fluoresce, that is, they glow. As soon as the radiation stops, the glow also disappears. If it continues after the cessation of the action of the rays, then this effect is called phosphorescence.
X-rays can illuminate photographic film, just like visible light.
If the beam passed through the air, then ionization occurs in the atmosphere. This state is called electrically conductive, and it is determined using a dosimeter, which sets the rate of radiation dosage.

Radiation - harm and benefit

When the discovery was made, the physicist Roentgen could not even imagine how dangerous his invention was. In the old days, all devices that produced radiation were far from perfect, and as a result, large doses of emitted rays were obtained. People did not understand the dangers of such radiation. Although some scientists even then put forward versions about the dangers of x-rays.

X-rays, penetrating into tissues, have a biological effect on them. The unit of measurement of radiation dose is roentgen per hour. The main influence is on the ionizing atoms that are inside the tissues. These rays act directly on the DNA structure of a living cell. The consequences of uncontrolled radiation include:

cell mutation;
the appearance of tumors;
radiation burns;
radiation sickness.

Contraindications for X-ray examinations:

The patients are in critical condition.
Pregnancy period due to negative effects on the fetus.
Patients with bleeding or open pneumothorax.

How x-rays work and where it is used

In medicine. X-ray diagnostics is used to translucent living tissues in order to identify certain disorders within the body. X-ray therapy is performed to eliminate tumor formations.
In science. The structure of substances and the nature of X-rays are revealed. These issues are dealt with by such sciences as chemistry, biochemistry, crystallography.
In industry. To detect violations in metal products.
For the safety of the population. X-ray beams are installed at airports and other public places to scan luggage.

Medical use of X-ray radiation. X-rays are widely used in medicine and dentistry for the following purposes:

For diagnosing diseases.
For monitoring metabolic processes.
For the treatment of many diseases.

The use of X-rays for medical purposes

In addition to detecting bone fractures, x-rays are widely used for medical purposes. The specialized application of x-rays is to achieve the following goals:

To destroy cancer cells.
To reduce the size of the tumor.
To reduce pain.

For example, radioactive iodine, used in endocrinological diseases, is actively used in thyroid cancer, thereby helping many people get rid of this terrible disease. Currently, to diagnose complex diseases, X-rays are connected to computers, as a result, the latest research methods appear, such as computed axial tomography.

Such a scan provides doctors with color images that show the internal organs of a person. To detect the work of internal organs, a small dose of radiation is sufficient. X-rays are also widely used in physiotherapy.

Basic properties of X-rays

penetrating ability. All bodies are transparent to the x-ray, and the degree of transparency depends on the thickness of the body. It is due to this property that the beam began to be used in medicine to detect the functioning of organs, the presence of fractures and foreign bodies in the body.
They are able to cause the glow of some objects. For example, if barium and platinum are applied to cardboard, then, after passing through the beam scanning, it will glow greenish-yellow. If you place your hand between the X-ray tube and the screen, then the light will penetrate more into the bone than into the tissue, so the bone tissue will shine brightest on the screen, and the muscle tissue will be less bright.
Action on film. X-rays can, like light, darken film, which makes it possible to photograph the shadow side that is obtained when objects are examined by x-rays.
X-rays can ionize gases. This makes it possible not only to find rays, but also to reveal their intensity by measuring the ionization current in the gas.
They have a biochemical effect on the body of living beings. Thanks to this property, X-rays have found their wide application in medicine: they can treat both skin diseases and diseases of internal organs. In this case, the desired dosage of radiation and the duration of the rays are selected. Prolonged and excessive use of such treatment is very harmful and detrimental to the body.

The consequence of the use of X-rays was the saving of many human lives. X-ray helps not only to diagnose the disease in a timely manner, treatment methods using radiation therapy relieve patients of various pathologies, from hyperfunction of the thyroid gland to malignant tumors of bone tissues.

The discovery and merit in the study of the basic properties of X-rays rightfully belongs to the German scientist Wilhelm Conrad Roentgen. The amazing properties of X-rays discovered by him immediately received a huge response in the scientific world. Although then, back in 1895, the scientist could hardly imagine what benefit, and sometimes harm, X-rays can bring.

Let's find out in this article how this type of radiation affects human health.

What is x-ray radiation

The first question that interested the researcher was what is X-ray radiation? A number of experiments made it possible to verify that this is electromagnetic radiation with a wavelength of 10 -8 cm, which occupies an intermediate position between ultraviolet and gamma radiation.

Application of X-rays

All these aspects of the destructive effects of the mysterious X-rays do not at all exclude surprisingly extensive aspects of their application. Where is X-rays used?

Study of the structure of molecules and crystals.
X-ray flaw detection (in industry, detection of defects in products).
Methods of medical research and therapy.

The most important applications of X-rays have become possible due to the very short wavelengths of the entire range of these waves and their unique properties.

Since we are interested in the impact of X-ray radiation on people who encounter it only during a medical examination or treatment, then we will only consider this area of application of X-rays.

The use of x-rays in medicine

Despite the special significance of his discovery, Roentgen did not take out a patent for its use, making it an invaluable gift for all mankind. Already in the First World War, X-ray units began to be used, which made it possible to quickly and accurately diagnose the wounded. Now we can distinguish two main areas of application of x-rays in medicine:

X-ray diagnostics;
x-ray therapy.

X-ray diagnostics

X-ray diagnostics is used in various options:

Let's take a look at the difference between these methods.

All of these diagnostic methods are based on the ability of x-rays to illuminate film and on their different permeability to tissues and the bone skeleton.

X-ray therapy

The ability of X-rays to have a biological effect on tissues is used in medicine for the treatment of tumors. The ionizing effect of this radiation is most actively manifested in the effect on rapidly dividing cells, which are the cells of malignant tumors.

However, you should also be aware of the side effects that inevitably accompany radiotherapy. The fact is that cells of the hematopoietic, endocrine, and immune systems are also rapidly dividing. A negative impact on them gives rise to signs of radiation sickness.

The effect of X-ray radiation on humans

Shortly after the remarkable discovery of X-rays, it was discovered that X-rays had an effect on humans.

These data were obtained in experiments on experimental animals, however, geneticists suggest that similar effects may apply to the human body.

The study of the effects of X-ray exposure has led to the development of international standards for acceptable radiation doses.

Doses of x-ray radiation in x-ray diagnostics

After visiting the X-ray room, many patients are worried - how will the received dose of radiation affect their health?

The dose of general irradiation of the body depends on the nature of the procedure. For convenience, we will compare the received dose with natural exposure, which accompanies a person throughout his life.

X-ray: chest - the received dose of radiation is equivalent to 10 days of background exposure; upper stomach and small intestine - 3 years.
Computed tomography of the abdominal cavity and pelvis, as well as the whole body - 3 years.
Mammography - 3 months.
Radiography of the extremities is practically harmless.
With regard to dental x-rays, the radiation dose is minimal, since the patient is exposed to a narrow beam of x-rays with a short radiation duration.

These radiation doses meet acceptable standards, but if the patient feels anxious before the X-ray, he has the right to ask for a special protective apron.

Exposure of X-rays to pregnant women

Each person has to undergo X-ray examination repeatedly. But there is a rule - this diagnostic method cannot be prescribed to pregnant women. The developing embryo is extremely vulnerable. X-rays can cause chromosome abnormalities and, as a result, the birth of children with malformations. The most vulnerable in this regard is the gestational age of up to 16 weeks. Moreover, the most dangerous for the future baby is an x-ray of the spine, pelvic and abdominal regions.

Knowing about the detrimental effect of x-rays on pregnancy, doctors avoid using it in every possible way during this crucial period in a woman's life.

However, there are side sources of X-rays:

electron microscopes;
color TV kinescopes, etc.

Expectant mothers should be aware of the danger posed by them.

For nursing mothers, radiodiagnosis is not dangerous.

What to do after an x-ray

To avoid even the minimal effects of X-ray exposure, some simple steps can be taken:

after an x-ray, drink a glass of milk - it removes small doses of radiation;
very handy taking a glass of dry wine or grape juice;
some time after the procedure, it is useful to increase the proportion of foods with a high content of iodine (seafood).

But, no medical procedures or special measures are required to remove radiation after an x-ray!

Despite the undoubtedly serious consequences of exposure to X-rays, one should not overestimate their danger during medical examinations - they are carried out only in certain areas of the body and very quickly. The benefits of them many times exceed the risk of this procedure for the human body.

X-RAY RADIATION

x-ray radiation occupies the region of the electromagnetic spectrum between gamma and ultraviolet radiation and is electromagnetic radiation with a wavelength of 10 -14 to 10 -7 m. X-ray radiation with a wavelength of 5 x 10 -12 to 2.5 x 10 -10 is used in medicine m, that is, 0.05 - 2.5 angstrom, and actually for X-ray diagnostics - 0.1 angstrom. Radiation is a stream of quanta (photons) propagating in a straight line at the speed of light (300,000 km/s). These quanta have no electric charge. The mass of a quantum is an insignificant part of the atomic mass unit.

Quantum energy measured in Joules (J), but in practice they often use an off-system unit "electron volt" (eV) . One electron volt is the energy that one electron acquires when it passes through a potential difference of 1 volt in an electric field. 1 eV \u003d 1.6 10 ~ 19 J. Derivatives are a kiloelectron volt (keV), equal to a thousand eV, and a megaelectron volt (MeV), equal to a million eV.

X-rays are obtained using X-ray tubes, linear accelerators and betatrons. In an X-ray tube, the potential difference between the cathode and the target anode (tens of kilovolts) accelerates the electrons bombarding the anode. X-ray radiation arises when fast electrons decelerate in the electric field of atoms of the anode substance (bremsstrahlung) or when rearranging the inner shells of atoms (characteristic radiation) . Characteristic X-rays has a discrete character and occurs when the electrons of the atoms of the anode substance pass from one energy level to another under the influence of external electrons or radiation quanta. Bremsstrahlung X-ray has a continuous spectrum depending on the anode voltage on the x-ray tube. When decelerating in the anode material, electrons spend most of their energy on heating the anode (99%) and only a small fraction (1%) is converted into X-ray energy. In X-ray diagnostics, bremsstrahlung is most often used.

The basic properties of X-rays are characteristic of all electromagnetic radiation, but there are some features. X-rays have the following properties:

- invisibility - sensitive cells of the human retina do not react to x-rays, since their wavelength is thousands of times smaller than that of visible light;

- rectilinear propagation - rays are refracted, polarized (propagated in a certain plane) and diffracted, like visible light. The refractive index differs very little from unity;

- penetrating power - penetrate without significant absorption through significant layers of a substance that is opaque to visible light. The shorter the wavelength, the greater the penetrating power of X-rays;

- absorbency - have the ability to be absorbed by the tissues of the body, this is the basis of all x-ray diagnostics. The ability to absorb depends on the specific gravity of the tissues (the more, the greater the absorption); on the thickness of the object; on the hardness of the radiation;

- photographic action - decompose silver halide compounds, including those found in photographic emulsions, which makes it possible to obtain x-rays;

- luminescent effect - cause the luminescence of a number of chemical compounds (phosphors), this is the basis of the X-ray transmission technique. The intensity of the glow depends on the structure of the fluorescent substance, its amount and distance from the source of x-rays. Phosphors are used not only to obtain an image of the objects under study on a fluoroscopic screen, but also in radiography, where they make it possible to increase the radiation exposure to a radiographic film in a cassette due to the use of intensifying screens, the surface layer of which is made of fluorescent substances;

- ionization action - have the ability to cause the decay of neutral atoms into positively and negatively charged particles, dosimetry is based on this. The effect of ionization of any medium is the formation of positive and negative ions in it, as well as free electrons from neutral atoms and molecules of a substance. The ionization of air in the X-ray room during the operation of the X-ray tube leads to an increase in the electrical conductivity of the air, an increase in static electric charges on the objects of the cabinet. In order to eliminate such an undesirable influence of them in X-ray rooms, forced supply and exhaust ventilation is provided;

- biological action - have an impact on biological objects, in most cases this impact is harmful;

- inverse square law - for a point source of X-ray radiation, the intensity decreases in proportion to the square of the distance to the source.

The German scientist Wilhelm Conrad Roentgen can rightly be considered the founder of radiography and the discoverer of the key features of X-rays.

Then back in 1895, he did not even suspect the breadth of application and popularity of X-radiation discovered by him, although even then they raised a wide resonance in the world of science.

It is unlikely that the inventor could have guessed what benefit or harm the fruit of his activity would bring. But today we will try to find out what effect this kind of radiation has on the human body.

X-radiation is endowed with a huge penetrating power, but it depends on the wavelength and density of the material that is irradiated;
under the influence of radiation, some objects begin to glow;
the x-ray affects living beings;
thanks to X-rays, some biochemical reactions begin to occur;
An x-ray beam can take electrons from some atoms and thereby ionize them.

Even the inventor himself was primarily concerned with the question of what exactly the rays discovered by him were.

After a whole series of experimental studies, the scientist found out that X-rays are intermediate waves between ultraviolet and gamma radiation, the length of which is 10 -8 cm.

The properties of the X-ray beam, which are listed above, have destructive properties, but this does not prevent them from being used for useful purposes.

So where in the modern world can X-rays be used?

They can be used to study the properties of many molecules and crystalline formations.
For flaw detection, that is, to check industrial parts and devices for defects.
In the medical industry and therapeutic research.

Due to the short lengths of the entire range of these waves and their unique properties, the most important application of the radiation discovered by Wilhelm Roentgen became possible.

Since the topic of our article is limited to the impact of X-rays on the human body, which encounters them only when going to the hospital, then we will consider only this branch of application.

The scientist who invented X-rays made them an invaluable gift for the entire population of the Earth, because he did not patent his offspring for further use.

Since World War I, portable x-ray machines have saved hundreds of wounded lives. Today, X-rays have two main applications:

Diagnosis with it.

X-ray diagnostics is used in various options:

X-ray or transillumination;
x-ray or photograph;
fluorographic study;
tomography using x-rays.

Now we need to understand how these methods differ from each other:

The first method assumes that the subject is located between a special screen with a fluorescent property and an X-ray tube. The doctor, based on individual characteristics, selects the required strength of the rays and receives an image of the bones and internal organs on the screen.
In the second method, the patient is placed on a special x-ray film in a cassette. In this case, the equipment is placed above the person. This technique allows you to get an image in the negative, but with finer details than with fluoroscopy.
Mass examinations of the population for lung disease allows for fluorography. At the time of the procedure, the image is transferred from a large monitor to a special film.
Tomography allows you to get images of internal organs in several sections. A whole series of images are taken, which are hereinafter referred to as a tomogram.
If you connect the help of a computer to the previous method, then specialized programs will create a complete image made using an x-ray scanner.

All these methods of diagnosing health problems are based on the unique property of X-rays to light up photographic film. At the same time, the penetrating ability of inert and other tissues of our body is different, which is displayed in the picture.

After another property of X-rays to influence tissues from a biological point of view was discovered, this feature began to be actively used in tumor therapy.

Cells, especially malignant ones, divide very quickly, and the ionizing property of radiation has a positive effect on therapeutic therapy and slows down tumor growth.

But the other side of the coin is the negative effect of x-rays on the cells of the hematopoietic, endocrine and immune systems, which also divide rapidly. As a result of the negative influence of the X-ray, radiation sickness manifests itself.

The effect of x-rays on the human body

Literally immediately after such a loud discovery in the scientific world, it became known that X-rays can affect the human body:

In the course of research on the properties of X-rays, it turned out that they are capable of causing burns on the skin. Very similar to thermal. However, the depth of the lesion was much greater than domestic injuries, and they healed worse. Many scientists dealing with these insidious radiations have lost their fingers.
By trial and error, it was found that if you reduce the time and vine of endowment, then burns can be avoided. Later, lead screens and the remote method of irradiating patients began to be used.
The long-term perspective of the harmfulness of rays shows that changes in the composition of the blood after irradiation leads to leukemia and early aging.
The degree of severity of the impact of X-rays on the human body directly depends on the irradiated organ. So, with X-rays of the small pelvis, infertility can occur, and with the diagnosis of hematopoietic organs - blood diseases.
Even the most insignificant exposures, but over a long period of time, can lead to changes at the genetic level.

Of course, all studies were conducted on animals, but scientists have proven that pathological changes will also apply to humans.

IMPORTANT! Based on the obtained data, X-ray exposure standards were developed, which are uniform throughout the world.

Doses of x-rays for diagnosis

Probably, everyone who leaves the doctor's office after an x-ray is wondering how this procedure will affect their future health?

Radiation exposure in nature also exists and we encounter it daily. To make it easier to understand how x-rays affect our body, we compare this procedure with the natural radiation received:

on a chest x-ray, a person receives a dose of radiation equivalent to 10 days of background exposure, and the stomach or intestines - 3 years;
tomogram on the computer of the abdominal cavity or the whole body - the equivalent of 3 years of radiation;
examination on chest x-ray - 3 months;
limbs are irradiated, practically without harming health;
dental x-ray due to the precise direction of the beam beam and the minimum exposure time is also not dangerous.

IMPORTANT! Despite the fact that the given data, no matter how frightening they may sound, meet international requirements. However, the patient has every right to ask for additional means of protection in case of strong fear for his well-being.

All of us are faced with x-ray examination, and more than once. However, one category of people outside of the prescribed procedures are pregnant women.

The fact is that X-rays extremely affect the health of the unborn child. These waves can cause intrauterine malformations as a result of the effect on the chromosomes.

IMPORTANT! The most dangerous period for x-rays is pregnancy before 16 weeks. During this period, the most vulnerable are the pelvic, abdominal and vertebral regions of the baby.

Knowing about this negative property of x-rays, doctors all over the world are trying to avoid prescribing it for pregnant women.

But there are other sources of radiation that a pregnant woman may encounter:

microscopes powered by electricity;
color TV monitors.

Those who are preparing to become a mother must be aware of the danger that awaits them. During lactation, X-rays do not pose a threat to the body of the nursing and the baby.

What about after the x-ray?

Even the most minor effects of X-ray exposure can be minimized by following a few simple recommendations:

drink milk immediately after the procedure. As you know, it is able to remove radiation;
dry white wine or grape juice has the same properties;
it is desirable at first to eat more foods containing iodine.

IMPORTANT! You should not resort to any medical procedures or use medical methods after visiting the x-ray room.

No matter how negative the properties of the once discovered X-rays, the benefits of their use far outweigh the harm. In medical institutions, the transillumination procedure is carried out quickly and with minimal doses.