1852 was born in France. Due to the discovery of natural radioactivity, pierre curie (1859- 1906) and Marie Curie (1867- 1934) received 65438+ for their in-depth research and outstanding contributions in radiology.

Chinese name: mbth, Antoine Henri Becquerel: Antoine Henri Becquerel Nationality: France Date of birth: 1852 Date of death: 1908 Occupation: physicist Graduate school: Paris Polytechnic University Major achievement: Nobel Prize 1903. Personal introduction: Bell Prize in Physics, life experience, radioactive discovery, natural radioactivity, biological radionuclide, personal introduction 1852 12 15 Antoine Henri Becquerel was born in Paris, France, and came from a prestigious family of scholars and scientists. His father Alexander Edmund becquerel is a professor of applied physics who studies solar radiation and phosphorescence. His grandfather Anthony Seiser was a member of the Royal Society. He was the inventor of extracting metals from minerals by electrolysis. Antoine Henri Becquerel1872 Bekkerel studied at the Polytechnic University of Paris, and later graduated from the Institute of Highway and Bridge with the position of engineer. 1878 Professor of Physics, Paris Museum of Natural History. Becquerel married Miller Jenin, the daughter of a civil engineer. 1878, they gave birth to a son, Ji 'an, who is also a physicist, the fourth generation physicist of becquerel family. 1895 Professor of Polytechnic University. 1896 in March, becquerel discovered the photosensitive soleplate, which was put together with potassium uranyl sulfate, but wrapped in black paper and was photosensitive. He speculated that this may be because uranium salts emit some unknown radiation. In May of the same year, he found that pure uranium metal plate can also produce this kind of radiation, thus confirming the discovery of natural radioactivity. Later, the Curies called it "radioactivity". We call it natural radioactivity. Although becquerel mistook it for a special form of fluorescence at that time, the discovery of natural radioactivity was still an epoch-making event, which opened the door to the microscopic world and laid the experimental foundation for the birth and development of nuclear physics and particle physics. 1908 is dead. Life experience1852 65438+February 65438+May Born in Paris. 1872, becquerel entered the Institute of Technology, and later in 1874, he joined the local government of Xiasas, Danset province. 1877 became an engineer, 1894 was promoted to chief engineer. 1888 received the doctor of science degree. 1878, working as a teaching assistant in the museum of natural history, inheriting his father's lecture on applied physics in the college of arts and crafts. 1892, becquerel was appointed as Professor of Applied Physics in the Department of Natural History of the Paris Museum. Antoine henri becquerel became a professor at the Institute of Comprehensive Technology from 65438 to 0895. Becquerel's early work focused on plane polarization of light, phosphorescence and absorption of light by crystals (this was the theme of his doctoral thesis). He also studied geomagnetic problems. 1896, because he discovered natural radioactivity, his early research work took a back seat. After discussing with H. Poincare the phenomenon that Roentgen recently discovered radiation (X-ray) and phosphorescence were produced simultaneously in a vacuum tube, becquerel decided to study whether there was a connection between X-ray and naturally occurring phosphorescence. He inherited some sodium salts from his father. Phosphorescence of sodium salt can be used for exposure. When he put the uranium salt near the photographic film wrapped in opaque paper, he found that the photographic film was exposed. This phenomenon is the same for all uranium salts tested, so he concluded that this is a characteristic of uranium atoms. Later, becquerel proved that the radiation was emitted by uranium. This ray has long been named after the surname of its discoverer. This kind of ray can ionize gas, but it is different from X-ray and can be deflected by electric or magnetic fields. Bekkerel won half of the Nobel Prize in Physics in 1903 for discovering natural radioactivity, and the other half was awarded to Mr. and Mrs. pierre curie for their research on Becquerel rays. 1889, becquerel was elected as an academician of the French Academy of Sciences and became the lifelong secretary of the Academy of Sciences after Berthelot. He was a member of the Lindsay Academy of Sciences and the Royal Academy of Sciences in Berlin. 1900 was appointed as an officer of the legion of honor. 1903 won the nobel prize in physics for discovering the radioactivity of substances. 1908 On August 25th, A.H. becquerel died in Loisik, Uelek. The discovery of radioactivity was first discovered by French physicist Henri Bekkerel, who is an expert in fluorescence and phosphorescence. At the beginning of 1996, Antoine Henri Bekkerel1896, Roentgen discovered that the information of X-rays spread to Paris, and an accidental opportunity made him encounter radioactive problems. There was a famous French mathematical physicist named Poincare. After receiving Roentgen's communication, he reported to the participants at the regular meeting of French Academy of Sciences on 18961October 20th, showing Roentgen's communication and X-ray photos. Becquerel happened to be there. He asked Poincare how this ray was produced. Poincare replied that it seems to be produced from the place opposite the cathode of the vacuum tube, which may belong to the same mechanism as fluorescence. Poincare also suggested that becquerel try whether fluorescence would be accompanied by X-rays. So the next day, becquerel began to test whether this fluorescent substance can radiate an invisible ray that can penetrate thick paper to make the negative film sensitive in his own laboratory. He tried and tried, and finally found a substance with expected effect. This substance is uranium salt. Becquerel took two pieces of thick black paper and wrapped the photosensitive film tightly, so that it wouldn't be sensitive even if it was exposed to the sun for a day. Then, he put the uranium salt on a negative wrapped in black paper and let it dry in the sun for several hours, which is very different. The negative shows a black shadow. In order to prove that radiation is at work, he specially put a layer of glass between the black paper bag and uranium salt, and then put it in the sun. If it is due to some chemical action or thermal effect, a layer of glass should be excluded, but there is still a shadow. So becquerel affirmed Poincare's hypothesis and reported the experimental results at the regular meeting of the French Academy of Sciences. A few days later, becquerel was ready to further explore this new phenomenon, but it was cloudy for several days in a row, and he had to put all the equipment, including wrapped negatives and uranium salts, in the same drawer. Perhaps out of some professional inspiration, becquerel suddenly had an idea to see if the film would turn black even if it was not exposed to the sun. So he developed the negative. I didn't expect the shadow on the negative to be really obvious. He carefully examined the scene and was convinced that these shadows were the result of uranium salts. Faced with this sudden phenomenon, becquerel soon realized that he had to give up his original hypothesis. This ray is not directly related to fluorescence. Unlike fluorescence, it does not need external light excitation. He continued his experiment and finally confirmed that it was the radiation from uranium itself. He called this radiation uranium radiation. Uranium radiation is different from x-rays. Although both of them have strong penetrating power, their mechanisms are different. On May 18 of the same year, he published a report in the French Academy of Sciences, saying that uranium radiation is a function of the atom itself, and as long as the elemental uranium exists, it will continue to be produced. This is the initial process of discovering radioactivity. Although this discovery is not as sensational as Roentgen's discovery of X-rays, its significance is still far-reaching. Because this event prepared the first cornerstone for the birth of nuclear physics. Becquerel's discovery was so accidental. If Poincare had not introduced the discovery of X-rays at the regular meeting of the French Academy of Sciences; If becquerel doesn't talk to Poincare; If becquerel did not take uranium salt as the test object; If it doesn't rain in Paris on February 26th-27th; If becquerel hadn't put the unexposed negatives in the drawer under the uranium salt; If he hadn't developed the unexposed negative unconsciously or curiously, maybe becquerel wouldn't have found radioactivity. In that case, radioactivity will not be discovered when and by whom, and the history of radiology and nuclear physics will be rewritten. Many people say that it is coincidence that makes becquerel lucky. Becquerel discovered radioactivity by accident, of course, but becquerel himself often told people that it was "completely logical" to find radioactivity in his laboratory. This logic refers to inevitability. The natural radiation background in natural radioactive environment is mainly composed of cosmic rays, cosmic radionuclides and radiation emitted by primary radionuclides. Cosmic rays mainly come from the outer space of the earth. In order to find out the source of cosmic rays, some people have done experiments to raise a large balloon equipped with nuclear radiation detection devices from sea level to high altitude and observe the relationship between the fluence rate of ionizing radiation particles and the height of sea level. The results show that when the altitude is below 700 meters, the particle fluence rate drops sharply with the increase of altitude. When the balloon height exceeds 700 meters, the particle fluence rate increases rapidly with the height. In addition, it is also found that the intensity of cosmic rays measured by the earth is obviously enhanced during solar flares, which proves that cosmic rays are generated in space outside the earth. There are primary and secondary cosmic rays. Primary cosmic rays refer to high-energy radiation emitted from outer space into the earth's atmosphere. According to different sources, primary cosmic rays can be divided into "primary galactic cosmic rays" and "primary solar cosmic rays". However, the former is the source of primary cosmic rays. The primary galactic cosmic rays are mainly composed of high-energy protons (~87%), accompanied by helium nuclei of about 10%, and the rest are small amounts of heavy particles, electrons, photons and neutrinos. Primary cosmic rays have great kinetic energy, so their penetrating ability is extremely strong. Primary solar cosmic rays mainly refers to charged particles released by solar flares, most of which are protons and alpha particles. However, these particles have low energy and usually have no obvious effect on the surface radiation dose. Secondary cosmic rays are the product of the interaction between high-energy primary cosmic rays and the atmosphere. When primary cosmic rays enter the atmosphere, particles with great energy collide violently with the nuclei in the atmosphere, resulting in the disintegration of the nuclei. This nuclear reaction is generally called "spallation reaction" or "fragmentation reaction". Generally speaking, cosmic rays are divided into "hard rays" and "soft rays" according to energy habits. "Hard" cosmic rays mainly refer to high-energy particles with strong penetrating ability, mainly refer to mesons and high-energy protons; "Soft" cosmic rays refer to low-energy particles that are easily absorbed by matter, mainly electrons and photons. When high-energy primary cosmic rays react with atomic nuclei in the atmosphere, the reaction products include many radionuclides besides secondary cosmic ray particles, which are called "cosmogenic radionuclides". Although there are many cosmogenic radionuclides in antoine henri becquerel's test photos, their content in the air is very low, so their actual contribution to environmental radiation, especially external radiation, is not great. However, the contribution of some nuclides in environmental radiation dose can not be ignored, and it is also of great significance in scientific research. Antoine henri becquerel's primary radionuclides and cosmogenic radionuclides belong to natural radionuclides. The difference between them is that the latter is the product of cosmic rays passing through and interacting with the atmospheric nucleus, while the former is those radionuclides that have existed in the crust since the formation of the earth. Therefore, it is called "primary" radionuclide. Obviously, there may be many radionuclides formed at the same time as the earth, of which only a few radionuclides with a long half-life may remain to this day. There are many kinds of natural radionuclides with different properties and states, which are widely distributed in the environment. There are traces of natural radionuclides in rocks, soil, air, water, animals and plants, building materials, food and even human body. The crust is an important repository of natural radionuclides, especially primary radionuclides. The radioactive substances in the earth's crust are mainly uranium, thorium and uranium. Among them, the natural radionuclides in the air mainly include radionuclides released from the surface to the atmosphere and their daughters, and the natural radionuclides in animal and plant foods are mostly. Soil is mainly produced by the erosion and weathering of rocks, which shows that radioactivity is transferred from rocks. Because of the variety of rocks and the different influence of natural conditions, it can be predicted that the concentration of natural radionuclides in soil changes greatly. The geographical location, geological sources, hydrological conditions, climate and agricultural history of soil are all important factors affecting the content of natural radionuclides in soil. Radioactive substances existing in rocks and soil are lost due to leaching of groundwater, and natural radionuclides in groundwater mainly come from this way. In addition, the radionuclides attached to the surface granular soil can be transformed into dust or aerosol under the action of wind, and then transferred to the atmosphere and further migrated to plants or animals. Some soluble radionuclides in soil are absorbed by plant roots, then transported to edible parts, eaten by herbivores, and then transferred to carnivores, and finally become one of the important sources of radionuclides in food and human body. The concentration of natural radionuclides in environmental water is related to many factors. In addition, natural radioactive substances also include cosmic rays. Cosmic rays are a stream of high-energy particles emitted from space to the earth. It consists of protons, particles, etc. Natural radioactivity has adapted to human beings without causing any harm.