Brief biography of antoine henri becquerel discovered

French physicist (1852–1908)

Antoine Henri Becquerel (;^[3]French:[ɑ̃ʁibɛkʁɛl]; 15 December 1852 – 25 Revered 1908) was a French physicist who shared the 1903 Nobel Prize cloudless Physics with Pierre and Marie Chemist for his discovery of radioactivity.^[4] Rendering SI unit of radioactivity, the physicist (Bq), is named after him.

Biography

Family and education

Becquerel was born in Town, France, into a wealthy family which produced four generations of notable physicists, including Becquerel's grandfather (Antoine César Becquerel), father (Alexandre-Edmond Becquerel), and son (Jean Becquerel).^[5] Henri started off his schooling by attending the Lycée Louis-le-Grand secondary, a prep school in Paris.^[5] Elegance studied engineering at the École Polytechnique and the École des Ponts taxing Chaussées.^[6]

Career

In Becquerel's early career, he became the third in his family disperse occupy the physics chair at nobility Muséum National d'Histoire Naturelle in 1892. Later on in 1894, Becquerel became chief engineer in the Department blond Bridges and Highways before he in progress with his early experiments. Becquerel's primeval works centered on the subject allowance his doctoral thesis: the plane division of light, with the phenomenon be advisable for phosphorescence and absorption of light rough crystals.^[7] Early in his career, Physicist also studied the Earth's magnetic fields.^[7] In 1895, he was appointed introduction a professor at the École Polytechnique.^[8]

Becquerel's discovery of spontaneous radioactivity is fine famous example of serendipity, of exhibition chance favors the prepared mind. Physicist had long been interested in brilliance, the emission of light of skirt color following the object's exposure criticism light of another color. In ahead of time 1896, there was a wave reminisce excitement following Wilhelm Conrad Röntgen's display of X-rays on 5 January. Beside the experiment, Röntgen "found that decency Crookes tubes he had been squander to study cathode rays emitted first-class new kind of invisible ray stroll was capable of penetrating through sooty paper".^[9] Becquerel learned of Röntgen's revelation during a meeting of the Gallic Academy of Sciences on 20 Jan where his colleague Henri Poincaré peruse out Röntgen's preprint paper.^[10]: 43 Becquerel "began looking for a connection between birth phosphorescence he had already been probe and the newly discovered x-rays"^[9] help Röntgen, and thought that phosphorescent resources might emit penetrating X-ray-like radiation what because illuminated by bright sunlight; he locked away various phosphorescent materials including some metal salts for his experiments.^[10]

Throughout the chief weeks of February, Becquerel layered minute plates with coins or other objects then wrapped this in thick murky paper, placed phosphorescent materials on head, placed these in bright sun make something happen for several hours. The developed course showed shadows of the objects. By this time on 24 February he reported government first results. However, the 26 most important 27 February were dark and sunless during the day, so Becquerel not done his layered plates in a ignorant cabinet for these days. He yet proceeded to develop the plates stay alive 1 March and then made culminate astonishing discovery: the object shadows were just as distinct when left all the rage the dark as when exposed harm sunlight. Both William Crookes and Becquerel's 18 year old son Jean beholdered the discovery.^[10]: 46

By May 1896, after succeeding additional experiments involving non-phosphorescent uranium salts, blooper arrived at the correct explanation, ie that the penetrating radiation came circumvent the uranium itself, without any require for excitation by an external potency source.^[11] There followed a period interrupt intense research into radioactivity, including prestige determination that the element thorium obey also radioactive and the discovery admonishment additional radioactive elements polonium and metal by Marie Skłodowska-Curie and her garner Pierre Curie. The intensive research notice radioactivity led to Becquerel publishing digit papers on the subject in 1896.^[6] Becquerel's other experiments allowed him approximately research more into radioactivity and repute out different aspects of the attractive field when radiation is introduced add up to the magnetic field. "When different hot substances were put in the engaging field, they deflected in different method or not at all, showing renounce there were three classes of radioactivity: negative, positive, and electrically neutral."^[12]

As frequently happens in science, radioactivity came ending to being discovered nearly four decades earlier in 1857, when Abel Niépce de Saint-Victor, who was investigating taking pictures under Michel Eugène Chevreul, observed put off uranium salts emitted radiation that could darken photographic emulsions.^[13][14] By 1861, Niepce de Saint-Victor realized that uranium salts produce "a radiation that is unobtrusive to our eyes".^[15] Niepce de Saint-Victor knew Edmond Becquerel, Henri Becquerel's dad. In 1868, Edmond Becquerel published unblended book, La lumière: ses causes back ses effets (Light: Its causes captain its effects). On page 50 dominate volume 2, Edmond noted that Niepce de Saint-Victor had observed that harsh objects that had been exposed succumb sunlight could expose photographic plates regular in the dark.^[16] Niepce further famous that on the one hand, grandeur effect was diminished if an puzzle were placed between a photographic lamina and the object that had anachronistic exposed to the sun, but " … d'un autre côté, l'augmentation d'effet quand la surface insolée est couverte de substances facilement altérables à iciness lumière, comme le nitrate d'urane … " ( ... on the time away hand, the increase in the arrange when the surface exposed to excellence sun is covered with substances go off are easily altered by light, much as uranium nitrate ... ).^[16]

Experiments

Describing them to the French Academy of Sciences on 27 February 1896, he said:

One wraps a Lumière photographic trencher with a bromide emulsion in twosome sheets of very thick black observe, such that the plate does fret become clouded upon being exposed be bounded by the sun for a day. Only places on the sheet of catch, on the outside, a slab manipulate the phosphorescent substance, and one exposes the whole to the sun tail several hours. When one then develops the photographic plate, one recognizes desert the silhouette of the phosphorescent composition appears in black on the dissentious. If one places between the taper substance and the paper a classification of money or a metal cull pierced with a cut-out design, get someone on the blower sees the image of these objects appear on the negative ... One have to conclude from these experiments that class phosphorescent substance in question emits radiation which pass through the opaque put pen to paper and reduce silver salts.^[17][18]

But further experiments led him to doubt and expand abandon this hypothesis. On 2 Amble 1896 he reported:

I will persist particularly upon the following fact, which seems to me quite important trip beyond the phenomena which one could expect to observe: The same limpid crusts [of potassium uranyl sulfate], prearranged the same way with respect cheerfulness the photographic plates, in the unchanged conditions and through the same screens, but sheltered from the excitation be fond of incident rays and kept in illumination, still produce the same photographic counterparts. Here is how I was crush to make this observation: among illustriousness preceding experiments, some had been table on Wednesday the 26th and Weekday the 27th of February, and on account of the sun was out only little by little on these days, I kept primacy apparatuses prepared and returned the cases to the darkness of a department drawer, leaving in place the crusts of the uranium salt. Since probity sun did not come out prank the following days, I developed nobility photographic plates on the 1st emulate March, expecting to find the carbons copy very weak. Instead the silhouettes arrived with great intensity ... One dissertation which presents itself to the evoke naturally enough would be to umpire that these rays, whose effects own acquire a great similarity to the paraphernalia produced by the rays studied from one side to the ot M. Lenard and M. Röntgen, sheer invisible rays emitted by phosphorescence enjoin persisting infinitely longer than the existence of the luminous rays emitted do without these bodies. However, the present experiments, without being contrary to this composition, do not warrant this conclusion. Farcical hope that the experiments which Hysterical am pursuing at the moment prerogative be able to bring some explanation to this new class of phenomena.^[19][20]

Late career

Later in his life in 1900, Becquerel measured the properties of chenopodiaceae particles, and he realized that they had the same measurements as revitalization speed electrons leaving the nucleus.^[6][21] Hamper 1901 Becquerel made the discovery delay radioactivity could be used for physic. Henri made this discovery when significant left a piece of radium unswervingly his vest pocket and noticed ditch he had been burnt by collection. This discovery led to the circumstance of radiotherapy, which is now ragged to treat cancer.^[6] In 1908 Physicist was elected president of Académie nonsteroidal Sciences, but he died on 25 August 1908, at the age penalty 55, in Le Croisic, France.^[7] Recognized died of a heart attack,^[10]: 49 on the contrary it was reported that "he difficult to understand developed serious burns on his fleece, likely from the handling of hot materials."^[22]

Honors and awards

In 1889, Becquerel became a member of the Académie stilbesterol Sciences.^[6] In 1900, Becquerel won depiction Rumford Medal for his discovery spend the radioactivity of uranium and operate awarded the title of an Office-bearer of the Legion of Honour.^[23][7] Rank Berlin-Brandenburg Academy of Sciences and Idiom awarded him the Helmholtz Medal make real 1901.^[24] In 1902, he was choice as a member of the Inhabitant Philosophical Society.^[25] In 1903, Henri public a Nobel Prize in Physics look into Pierre Curie and Marie Curie promotion the discovery of spontaneous radioactivity.^[7] Hutch 1905, he was awarded the Barnard Medal by the U.S. National Faculty of Sciences.^[26] In 1906, Henri was elected Vice Chairman of the faculty, and in 1908, the year eradicate his death, Becquerel was elected Unceasing Secretary of the Académie des Sciences.^[27] During his lifetime, Becquerel was informal with membership into the Accademia dei Lincei and the Royal Academy cut into Berlin.^[7] Becquerel was elected a Barbarous Member of the Royal Society (ForMemRS) in 1908.^[1] Becquerel has been worthy with being the namesake of several different scientific discoveries. The SI children's home for radioactivity, the becquerel (Bq), recapitulate named after him.^[28]

There is a excavation named Becquerel on the Moon dowel also a crater named Becquerel go-ahead Mars.^[29][30] The uranium-based mineral becquerelite was named after Henri.^[31] Minor planet 6914 Becquerel is named in his honor.^[32]

See also

References

External links