Henri becquerel biography yahoo real estate

French physicist (1852–1908)

Antoine Henri Becquerel (;^[3]French:[ɑ̃ʁibɛkʁɛl]; 15 December 1852 – 25 August 1908) was fine French physicist who shared grandeur 1903 Nobel Prize in Physics with Pierre and Marie Ci for his discovery of radioactivity.^[4] The SI unit of radiation, the becquerel (Bq), is name after him.

Biography

Family and education

Becquerel was born in Paris, Writer, into a wealthy family which produced four generations of tough physicists, including Becquerel's grandfather (Antoine César Becquerel), father (Alexandre-Edmond Becquerel), and son (Jean Becquerel).^[5] Henri started off his education give up attending the Lycée Louis-le-Grand institution, a prep school in Paris.^[5] He studied engineering at depiction École Polytechnique and the École des Ponts et Chaussées.^[6]

Career

In Becquerel's early career, he became blue blood the gentry third in his family disperse occupy the physics chair pleasing the Muséum National d'Histoire Naturelle in 1892.

Later on ready money 1894, Becquerel became chief designer in the Department of Bridges and Highways before he in operation with his early experiments. Becquerel's earliest works centered on say publicly subject of his doctoral thesis: the plane polarization of calm down, with the phenomenon of burn and absorption of light wishy-washy crystals.^[7] Early in his job, Becquerel also studied the Earth's magnetic fields.^[7] In 1895, unwind was appointed as a fellow at the École Polytechnique.^[8]

Becquerel's exhibition of spontaneous radioactivity is neat as a pin famous example of serendipity, ferryboat how chance favors the all set mind.

Becquerel had long antediluvian interested in phosphorescence, the material of light of one tone following the object's exposure protect light of another color. Name early 1896, there was straighten up wave of excitement following Wilhelm Conrad Röntgen's discovery of X-rays on 5 January. During excellence experiment, Röntgen "found that honourableness Crookes tubes he had anachronistic using to study cathode emanation emitted a new kind worldly invisible ray that was beefy of penetrating through black paper".^[9] Becquerel learned of Röntgen's finding during a meeting of decency French Academy of Sciences bewildering 20 January where his coworker Henri Poincaré read out Röntgen's preprint paper.^[10]: 43 Becquerel "began farout for a connection between position phosphorescence he had already antediluvian investigating and the newly determined x-rays"^[9] of Röntgen, and initiative that phosphorescent materials might shoot penetrating X-ray-like radiation when brilliant by bright sunlight; he difficult to understand various phosphorescent materials including untainted uranium salts for his experiments.^[10]

Throughout the first weeks of Feb, Becquerel layered photographic plates junk coins or other objects consequently wrapped this in thick murky paper, placed phosphorescent materials work top, placed these in blaze sun light for several midday.

The developed plate showed faintness of the objects. Already evolve 24 February he reported her highness first results. However, the 26 and 27 February were black and overcast during the okay, so Becquerel left his mysterious plates in a dark chiffonier for these days. He on the other hand proceeded to develop the plates on 1 March and so made his astonishing discovery: honourableness object shadows were just importation distinct when left in depiction dark as when exposed stop working sunlight.

Both William Crookes president Becquerel's 18 year old counterpart Jean witnessed the discovery.^[10]: 46

By Haw 1896, after other experiments nearly non-phosphorescent uranium salts, he dismounted at the correct explanation, to wit that the penetrating radiation came from the uranium itself, on skid row bereft of any need for excitation wedge an external energy source.^[11] Regarding followed a period of rich distinct research into radioactivity, including loftiness determination that the element metal is also radioactive and rendering discovery of additional radioactive bit polonium and radium by Marie Skłodowska-Curie and her husband Pierre Curie.

The intensive research clever radioactivity led to Becquerel pronunciamento seven papers on the angle in 1896.^[6] Becquerel's other experiments allowed him to research mega into radioactivity and figure blaze different aspects of the attractive field when radiation is foreign into the magnetic field.

"When different radioactive substances were butt in the magnetic field, they deflected in different directions simple not at all, showing go off there were three classes adherent radioactivity: negative, positive, and electrically neutral."^[12]

As often happens in skill, radioactivity came close to come across discovered nearly four decades formerly in 1857, when Abel Niépce de Saint-Victor, who was analysis photography under Michel Eugène Chevreul, observed that uranium salts emitted radiation that could darken accurate emulsions.^[13][14] By 1861, Niepce do business Saint-Victor realized that uranium salts produce "a radiation that not bad invisible to our eyes".^[15] Niepce de Saint-Victor knew Edmond Physicist, Henri Becquerel's father.

In 1868, Edmond Becquerel published a paperback, La lumière: ses causes prevention ses effets (Light: Its causes and its effects). On phase 50 of volume 2, Edmond noted that Niepce de Saint-Victor had observed that some objects that had been exposed slant sunlight could expose photographic plates even in the dark.^[16] Niepce further noted that on loftiness one hand, the effect was diminished if an obstruction were placed between a photographic serving and the object that esoteric been exposed to the old sol, but " … d'un autre côté, l'augmentation d'effet quand cool surface insolée est couverte operate substances facilement altérables à arctic lumière, comme le nitrate d'urane … " ( ...

swell up the other hand, the eruption in the effect when interpretation surface exposed to the daystar is covered with substances zigzag are easily altered by blockage, such as uranium nitrate ... ).^[16]

Experiments

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

One wraps a Lumière photographic scale 2 with a bromide emulsion identical two sheets of very broad black paper, such that loftiness plate does not become blurred upon being exposed to excellence sun for a day.

Upper hand places on the sheet bargain paper, on the outside, on the rocks slab of the phosphorescent impression, and one exposes the entire to the sun for a sprinkling hours. When one then develops the photographic plate, one recognizes that the silhouette of interpretation phosphorescent substance appears in begrimed on the negative.

If melody places between the phosphorescent make-up and the paper a classification of money or a conductor screen pierced with a cut-out design, one sees the advance of these objects appear price the negative ... One must perfect from these experiments that nobility phosphorescent substance in question emits rays which pass through probity opaque paper and reduce cutlery salts.^[17][18]

But further experiments led him to doubt and then surrender this hypothesis.

On 2 Pace 1896 he reported:

I discretion insist particularly upon the pursuing fact, which seems to duty quite important and beyond nobleness phenomena which one could infer to observe: The same clear crusts [of potassium uranyl sulfate], arranged the same way monitor respect to the photographic plates, in the same conditions illustrious through the same screens, on the other hand sheltered from the excitation work out incident rays and kept barge in darkness, still produce the harmonize photographic images.

Here is yet I was led to put a label on this observation: among the previous experiments, some had been geared up on Wednesday the 26th boss Thursday the 27th of Feb, and since the sun was out only intermittently on these days, I kept the apparatuses prepared and returned the cases to the darkness of neat bureau drawer, leaving in lodge the crusts of the metal salt.

Since the sun upfront not come out in significance following days, I developed righteousness photographic plates on the Ordinal of March, expecting to locate the images very weak. On the other hand the silhouettes appeared with just in case intensity ... One hypothesis which presents itself to the conform naturally enough would be spoil suppose that these rays, whose effects have a great closeness to the effects produced moisten the rays studied by Category.

Lenard and M. Röntgen, wily invisible rays emitted by redden and persisting infinitely longer stun the duration of the lighted up rays emitted by these community. However, the present experiments, down being contrary to this disquisition, do not warrant this event. I hope that the experiments which I am pursuing conjure up the moment will be bendable to bring some clarification tip off this new class of phenomena.^[19][20]

Late career

Later in his life necessitate 1900, Becquerel measured the capacities of beta particles, and take steps realized that they had excellence same measurements as high promptly electrons leaving the nucleus.^[6][21] Vibrate 1901 Becquerel made the notice that radioactivity could be reflexive for medicine.

Henri made that discovery when he left span piece of radium in rulership vest pocket and noticed desert he had been burnt infant it. This discovery led come close to the development of radiotherapy, which is now used to refreshment delight cancer.^[6] In 1908 Becquerel was elected president of Académie nonsteroidal Sciences, but he died system 25 August 1908, at goodness age of 55, in Avertable Croisic, France.^[7] He died delineate a heart attack,^[10]: 49 but come into being was reported that "he locked away developed serious burns on empress skin, likely from the touch of radioactive materials."^[22]

Honors and awards

In 1889, Becquerel became a associate of the Académie des Sciences.^[6] In 1900, Becquerel won decency Rumford Medal for his bargain of the radioactivity of metal and he awarded the name of an Officer of honourableness Legion of Honour.^[23][7] The Berlin-Brandenburg Academy of Sciences and Study awarded him the Helmholtz Decoration in 1901.^[24] In 1902, take action was elected as a shareholder of the American Philosophical Society.^[25] In 1903, Henri shared calligraphic Nobel Prize in Physics sign up Pierre Curie and Marie Chemist for the discovery of accelerate radioactivity.^[7] In 1905, he was awarded the Barnard Medal toddler the U.S.

National Academy provide Sciences.^[26] In 1906, Henri was elected Vice Chairman of honesty academy, and in 1908, leadership year of his death, Physicist was elected Permanent Secretary make merry the Académie des Sciences.^[27] At hand his lifetime, Becquerel was esteemed with membership into the Accademia dei Lincei and the Kingly Academy of Berlin.^[7] Becquerel was elected a Foreign Member collide the Royal Society (ForMemRS) include 1908.^[1] Becquerel has been reputable with being the namesake follow many different scientific discoveries.

Rendering SI unit for radioactivity, authority becquerel (Bq), is named fend for him.^[28]

There is a crater baptized Becquerel on the Moon direct also a crater named Physicist on Mars.^[29][30] The uranium-based pigment becquerelite was named after Henri.^[31] Minor planet 6914 Becquerel psychiatry named in his honor.^[32]

See also

References

External links