From Big Medical Encyclopedia

NUCLEAR WEAPON (ustar. atomic weapons) — the weapons of mass destruction of explosive action based on use of intranuclear energy. An energy source are or a nuclear fission test of heavy-nuclei (e.g., uranium-233 or uranium-235, plutonium-239), or thermonuclear synthetic reaction of easy kernels (see. Nuclear reactions).

Development I. began the lake at the beginning of the 40th 20 century at the same time in several countries after scientific data

on a possibility of the chain reaction of uranium fission which is followed by allocation of a huge number of energy were obtained. Under the leadership of the ital. physicist Fermi (E. Fermi) in 1942 was designed and started up in the USA the first nuclear reactor. The group of the American scientists led by R. Oppenheimer in 1945 created and tested the first atomic bomb.

In the USSR scientific developments in this area I. V. Kurchatov directed. The first testing of an atomic bomb is carried out in 1949, and thermonuclear — in 1953.

Nuclear weapon includes nuclear ammunition (the military units of rockets, aviation bombs, artillery shells, mines, land mines equipped with nuclear charges), their delivery systems to the purpose (rockets, torpedoes, airplanes), and also various control facilities providing hit of ammunition in the purpose. Depending on type of a charge it is accepted to distinguish nuclear, thermonuclear, neutron weapon. Power of nuclear ammunition is estimated by a trotyl equivalent, to-ry can make from several tens tons to several tens millions tons trotyl.

Nuclear explosions can be air, land, underground, surface, underwater and high-rise. They differ on an arrangement of the center of explosion of rather land or water surface and have the specific features. At explosion in the atmosphere at the height less than 30 thousand meters for a shockwave it is spent apprx. 50% of energy, and for light radiation — 35% of energy. With increase in height of explosion (at the smaller density of the atmosphere) the share of energy falling on a shockwave decreases, and light radiation increases. At land explosion light radiation decreases, and at underground — can even be absent. At the same time energy of explosion is the share of a penetrating radiation, radioactive infection and an electromagnetic impulse.

Air nuclear explosion is characterized by emergence of the shining area of spherical shape — a so-called fiery sphere. As a result of expansion of gases in a fiery sphere the shockwave is formed, edges extends extensively with a supersonic speed. During the passing of a shockwave across the area with a difficult relief perhaps both strengthening, and weakening of its action. Light radiation is emitted in the period of a luminescence of a fiery sphere and extends with velocity of light to long distances. It sufficiently is late any opaque objects. Primary penetrating radiation (neutrons and gamma-rays) has the striking effect during about 1 sec. from the moment of explosion; it is poorly absorbed by plugging materials. However its intensity quickly enough decreases with increase in distance from the center of explosion. Residual radoactive radiation — the products of nuclear explosion (PNE)

representing mix of more than 200 isotopes of 36 elements with half-life from fractions of a second to millions of years are carried on the planet on thousands of kilometers (global losses). At explosions of nuclear ammunition of low power primary penetrating radiation has the most expressed striking effect. With increase in power of a nuclear charge the share of gamma neutron emission in the striking action of factors of explosion decreases due to more intensive operation of a shockwave and light radiation.

At land nuclear explosion the fiery sphere concerns the Earth's surface. In this case thousands of tons of the evaporated soil are involved in the area of a fiery sphere. In epicenter of explosion there is a funnel surrounded with the melted-off soil. From the formed fungoid cloud about a half of PYaV is besieged on the Earth's surface in the direction of wind therefore the so-called radioactive trace appears, to-ry can reach not however

ky hundreds and thousands of square kilometers. Other radioactive materials, the being hl. obr. in highly disperse state, are carried away in an upper atmosphere and drop out on the earth as well as at air explosion. At underground nuclear explosion soil or is not thrown out (camouflage explosion), or partially is thrown out outside with formation of a funnel. The marked-out energy is absorbed by soil near the center of explosion therefore seismic waves are created. At underwater nuclear explosion the huge gas bubble and a water column (sultan) topped with a radioactive cloud is formed. Explosion comes to the end with formation of a basic wave and a series of gravitational waves. One of the most important effects of high-rise nuclear explosion is education under the influence of x-ray, gamma radiation and neutron emission of extensive areas of the increased ionization of an upper atmosphere.

Thus, I. the lake represents qualitatively new weapon

much surpassing in the striking action known earlier.

At the final stage of World War II of the USA applied I. the lake, having dropped nuclear bombs on the Japanese cities of Hiroshima and Nagasaki. Strong destructions were result of it (in Hiroshima from 75 thousand buildings it was destroyed or about 60 thousand, and in Nagasaki from 52 thousand — more than 19 thousand), the fires, especially in districts with wooden structures, a huge number of the human victims (see the table are considerably damaged). At the same time the closer people were to epicenter of explosion, the more often there were defeats and the they were heavier. So, in a radius up to 1 km vast majority of people sustained the damage, various on character, which ended preferential with death, and to the radius from 2,5 to 5 km of defeat in the basic were not heavy. In structure of sanitary losses the damages caused as isolated, and the combined influence of the striking factors of explosion were noted.

The table QUANTITY of PORAZHENNYH V to HIROSHIMA AND NAGASAKI (by materials of the book «Action of an Atomic Bomb in Japan», M., 1960)

the Striking action of an air shockwave is determined by hl. obr. the maximal excessive pressure in the front of a wave and a high-speed pressure. The excessive pressure of 0,14 — 0,28 kg/cm2 usually causes lungs, and 2,4 kg/cm2 — serious injuries. Damages from immediate effect of a shockwave carry to primary. They are characterized by signs of an accident and contusional syndrome, the closed brain injury, bodies of a breast and stomach. Secondary damages arise owing to a collapse of structures, influence of the flying stones, glass (secondary shells), etc. The nature of such injuries depends on the shock speed, weight, density, a form and the angle of contact of a secondary shell with a body of the person. Allocate also tertiary damages, to-rye are result of throwing action of a shockwave. Secondary and tertiary damages can be the most various, just as damages during the falling from height, transport accidents and other accidents.

Light radiation of nuclear explosion — electromagnetic radiation in an ultraviolet, visible and infrared spectrum — proceeds in two phases. In the first phase proceeding thousand — the 100-th fractions of a second, it is emitted apprx. 1% of energy, generally in an ultra-violet part of a range. Due to the short duration of action and absorption of a considerable part of waves air this phase practically does not matter in the all-striking effect of light radiation. The second phase is characterized by the radiation of hl. obr. in visible and infrared parts of a range and generally defines the striking effect. The dose of light radiation necessary for developing of burns of a certain depth depends on the power of explosion. So, e.g., burns of the II degree at explosion

of the 1 kiloton nuclear charge arise already at a dose of the light radiation of 4 kcal! cm2, and the 1 megaton — at a dose of the light radiation of 6,3 kcal! cm2. It is connected with the fact that at explosions of nuclear charges of low power light energy is emitted and influences the person the tenth fractions of a second, at explosion of bigger power time of radiation and influence of light energy increases up to several seconds. Immediate effect of light radiation on the person

is resulted by so-called primary burns. They make 80 — 90% of total number of thermal injuries in the center of defeat. Burns of skin at struck in Hiroshima and Nagasaki were localized generally on the body parts which are not protected by clothes, is preferential on a face and extremities. The people who were at distance to 2,4 km from epicenter of explosion had them deep, and at farther distance — superficial. Burns had accurate contours and were located only on the side of a body turned towards explosion. The configuration of a burn often corresponded to outlines of the objects shielding radiation.

Light radiation can cause temporary dazzle and organic lesion of eyes. It is the most probable at night when the pupil is expanded. Temporary dazzle usually lasts several minutes (up to 30 min.) then sight is completely recovered. Organic lesions — an acute keratoconjunctivitis and, especially, chorioretinal burns can lead to permanent dysfunctions of an organ of sight (see Burns).

Gamma neutron emission, influencing an organism, causes radiation (beam) damages. Neutrons in comparison with gamma radiation possess more expressed biol. activity and the damaging action at the molecular, cellular and organ levels. In process of removal from the center of explosion intensity of a neutron flux decreases quicker, than intensity of gamma radiation. So, the layer of air of 150 — 200 m reduces intensity of gamma radiation approximately twice, and intensity of a neutron flux — by 3 — 3V2 times.

In the conditions of use I. lakes radiation injuries can arise at the general rather uniform and uneven irradiation. Radiation is referred to uniform when the penetrating radiation influences all organism, and difference of doses on separate body parts insignificant. It is possible in case of finding of the person at the time of nuclear explosion on the open area or on a trace of a radioactive cloud. At such radiation with increase in an absorbed dose of radiation consistently there are signs of dysfunction of radio sensitive bodies and systems (marrow, intestines, c. N of page) also a certain wedge, forms of a radial illness — marrowy, transitional, intestinal, toxemic, cerebral develop. Uneven radiation arises in cases of local protection of separate body parts elements of fortification constructions, the equipment, etc.

At the same time various bodies are damaged unevenly that affects clinic of a radial illness. So, e.g., at general irradiation with preferential impact of radiation on area of the head can develop nevrol. disturbances, and with preferential impact on area of a stomach — segmented radiation colitis, enteritis. Besides, at the radial illness resulting from radiation with dominance of a neutron component priming reaction is stronger expressed, the eclipse period is less long; in the period of a heat of a disease, in addition to the general a wedge, signs, disorders of function of intestines are noted. Estimating biol. action of neutrons in general, it is also necessary to consider their adverse influence on the genetic device somatic and sex cells in this connection danger of the remote radiological effects at the irradiated people and their descendants (increases see. Radial illness).

On a trace of a radioactive cloud the main part of an absorbed dose is the share of the external prolonged gamma irradiation. However at the same time development of the combined radiation defeat when PYaV at the same time influence directly open body parts is possible and arrive in an organism. Such defeats are characterized by clinic of an acute radial illness, beta burns of skin, and also an internal injury, to the Crimea radioactive materials have raised tracks-nost (see Incorporation of radioactive materials).

At impact on an organism of all striking factors there are combined defeats. In Hiroshima and Nagasaki among the victims who survived for the 20th day after use I. the lake, such struck made respectively 25,6 and 23,7%. The combined defeats are characterized by earlier approach of a radial illness and its heavy current owing to the complicating influence of mechanical injuries and burns. Besides, erectile is extended and the torpid phase of shock goes deep, reparative processes are perverted, often there are heavy purulent complications (see. The combined defeats).

In addition to defeat of people, it is necessary to consider also the mediated influence I. the lake — destruction of structures, destruction of stocks of food, disturbance of water handling, sewerages, power food, etc. therefore the problem of placement, food of people, holding anti-epidemic actions, rendering significantly increases in so unfavorable conditions of medical aid to a huge number of struck.

The provided data demonstrate that sanitary losses in war using I. lakes will significantly differ from those in wars of the past. This difference generally consists in the following: in the previous wars mechanical injuries, and in war using I prevailed. lakes along with them considerable specific weight will occupy the radiation, thermal and combined defeats which are followed by a high lethality. Use I. the lake will be characterized by emergence of the centers of mass sanitary losses; at the same time in connection with mass character of defeats and single-step receipt of a large number of victims the number of persons in need in medical aid considerably will exceed real opportunities of medical service of army and especially medical service GO (see. Health service of Civil protection). In war using I. lakes will be erased sides between army and front districts of field army and the deep back of the country, and a dignity. losses among civilians will exceed considerably losses in troops.

Activity of medical service in so difficult situation shall be based on the uniform organizational, tactical and methodical principles of military medicine formulated still by N. I. Pirogov and in the subsequent developed by the Soviet scientists (see Medicine military, System of medical and evacuation providing, Stage treatment, etc.). At mass arrival of wounded and patients it is necessary to allocate first of all persons with defeats, incompatible with life. The qualified help shall be given in conditions when the number of wounded and patients many times over surpasses real opportunities of health service, when it allows to save life the victim. The sorting (see Sorting medical) which is carried out from such positions will promote the most rational use of medical forces and means for the solution of the main task — to give help in each case to most of wounded and patients.

Ecological effects of use of nuclear weapon in recent years draw the increasing attention of scientists, especially the specialists studying the long-term results of massive use of modern types I. lake. In detail and scientifically reasonably problem of ecological effects of use I. by the lake it was considered in the report of the International committee of experts in the field of medicine and public health care of «An effect of nuclear war for health of the population and health services» at the XXXVI session of the World assembly of health care which took place in May, 1983. This report was developed by the specified committee of experts including authoritative representatives of medical science and health care of 13 states (in t. h Great Britain, the USSR, the USA, France and Japan), in pursuance of the resolution of WHA 34.38 adopted by the XXXIV session of the World assembly of health care on May 22, 1981 the Soviet Union in this committee was represented by prominent scientists — specialists in the field of radiation biology, hygiene and medical protection academicians of the USSR Academy of Medical Sciences N. P. Bochkov and L. A. Ilyin.

The major factors arising at massirobathing use I. lakes, to-rye can cause catastrophic ecological effects, according to modern views, are: the destroyer

of Nov influence of the striking factors I. the lake on the biosphere of Earth involving total destruction of fauna and a vegetable cover in the territory which underwent such influence; jump of composition of the atmosphere of Earth as a result of decrease in a share of oxygen and its pollution by products of nuclear explosion, and also the nitric oxides released into the atmosphere from a zone of the fires raging on the earth, carbon and a huge number of the dark fine particles having high light-absorbing properties.

As the numerous researches executed by scientists of many countries, the intensive caloradiance making apprx. 35% of the energy released as a result of thermonuclear explosion testify will have the strong igniting effect and will lead to ignition practically of all combustible materials which are in districts of drawing nuclear attacks. The flame will capture the huge areas of the woods, peat bogs and settlements. Under the influence of a shockwave of nuclear explosion lines of giving (pipelines) of oil and natural gas can be damaged, and the combustible material which came to light still more will strengthen seats of fire. The so-called fiery hurricane will result, temperature to-rogo can reach 1000 °; it will proceed a long time, covering all new sites of the land surface and turning them into the lifeless ashes.

Especially the top coats of the soil which are important most for ecological system in general as they have ability to hold moisture will suffer and are the habitat of the organisms providing the processes happening in the soil biol. decomposition and metabolism. As a result of such adverse ecological shifts soil erosion under the influence of wind and an atmospheric precipitation, and also evaporation of moisture from the bared grounds will amplify. All this finally will lead to transformation of once prospering and fertile regions into the lifeless desert.

The smoke from the huge fires which mixed up with solid particles of products of land nuclear explosions will shroud a big or smaller surface (that I depend on scales of use. lake) the globe a dense cloud, a cut will absorb a considerable part of sunbeams. This blackout at simultaneous cooling of the land surface (so-called thermonuclear winter) can proceed a long time, exerting destructive influence on ecological system of the territories far remote from zones of direct use I. lake. At the same time it is also necessary to consider long teratogenic impact on ecological system of the specified territories of global radioactive fallout.

Extremely adverse ecological effects of use I. lakes will be result of also sharp reduction of content of ozone in a blanket of the terrestrial atmosphere as a result of its pollution by the nitric oxides emitted at explosion of nuclear ammunition of big power that will cause destruction of this blanket providing natural biol. protection of cells of animal and vegetable organisms against harmful effects At Physical spearing of the Sun. Disappearance of a vegetable cover in extensive territories in combination with pollution of the atmosphere can lead to serious climate changes, in particular to essential decrease in annual average temperature to both its sharp daily allowance and seasonal fluctuations.

Thus, catastrophic ecological effects of use I. lakes are caused: total destruction of the habitat of an animal and flora on the Earth's surface in the extensive zones which underwent immediate effect I. lake; long pollution of the atmosphere the thermonuclear smog which is extremely negatively influencing ecological system of all globe and causing climate changes; long teratogenic influence of the global radioactive fallout which are dropping out of the atmosphere on the Earth's surface, on the ecological system which partially remained in the zones which did not undergo total destruction by the striking factors I. lake. According to the conclusion recorded in the report of the International committee of experts, submitted to the XXXVI session of the World assembly of health care damage caused to an ecosystem by use I. lake, signs constant and, perhaps, irreversible character.

In a crust, time the most important task for mankind is preservation of peace, prevention of nuclear war. Fight for preservation and strengthening of the universal peace, restraint of a race of arms was and remains the rod direction of foreign policy activity of the CPSU and Soviet state. The USSR took and takes persistent steps in this direction. The most specific large-scale proposals of the CPSU found reflection in the Political report of the Secretary general of the Central Committee of the CPSU M. S. Gorbachev to the XXVII congress of the CPSU, in Krom basic Bases of comprehensive system of the international security were put forward.

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