Friday, December 4, 2015

Marie Curie

Posted by Unknown On 10:17 PM
 Marie Skłodowska Curie  
            Maria Skłodowska was born in Warsaw, in the Russian partition of Poland, on 7 November 1867, as the fifth and youngest child of well-known teachers Bronisława, née Boguska, and Władysław Skłodowski. Maria's older siblings were Zofia (born 1862), Józef (1863), Bronisława (1865) and Helena (1866)On both the paternal and maternal sides, the family had lost their property and fortunes through patriotic involvements in Polish national uprisings aimed at restoring Poland's independence (the most recent had been the January Uprising of 1863–65). This condemned the subsequent generation, including Maria, her elder sisters and her brother, to a difficult struggle to get 

Ahead in life
      Maria's paternal grandfather, Józef Skłodowski, had been a respected teacher in Lublin, where he taught the young Bolesław Prus, who would become a leading figure in Polish literature. Her father, Władysław Skłodowski, taught mathematics and physics, subjects that Maria was to pursue, and was also director of two Warsaw gymnasia for boys. After Russian authorities eliminated laboratory instruction from the Polish schools, he brought much of the laboratory equipment home, and instructed his children in its use.

     The father was eventually fired by his Russian supervisors for pro-Polish sentiments, and forced to take lower-paying posts; the family also lost money on a bad investment, and eventually chose to supplement their income by lodging boys in the house. Maria's mother Bronisława operated a prestigious Warsaw boarding school for girls; she resigned from the position after Maria was born. She died of tuberculosis in May 1878, when Maria was ten years old. Less than three years earlier, Maria's oldest sibling, Zofia, had died of typhus contracted from a boarder. Maria's father was an atheist; her mother a devout Catholic. The deaths of Maria's mother and sister caused her to give up Catholicism and become agnostic.

        When she was ten years old, Maria began attending the boarding school of J. Sikorska; next she attended a gymnasium for girls, from which she graduated on 12 June 1883 with a gold medal. After a collapse, possibly due to depression, she spent the following year in the countryside with relatives of her father, and the next year with her father in Warsaw, where she did some tutoring.Unable to enroll in a regular institution of higher education because she was a woman, she and her sister Bronisława became involved with the clandestine Flying University, a Polish patriotic institution of higher learning that admitted women studentsMaria made an agreement with her sister, Bronisława, that she would give her financial assistance during Bronisława's medical studies in Paris, in exchange for similar assistance two years later. In connection with this, Maria took a position as governess: first as a home tutor in Warsaw; then for two years as a governess in Szczuki with a landed family, the Żorawskis, who were relatives of her father.While working for the latter family, she fell in love with their son, Kazimierz Żorawski, a future eminent mathematician. His parents rejected the idea of his marrying the penniless relative, and Kazimierz was unable to oppose them.Maria's loss of the relationship with Żorawski was tragic for both. He soon earned a doctorate and pursued an academic career as a mathematician, becoming a professor and rector of Kraków University. Still, as an old man and a mathematics professor at the Warsaw Polytechnic, he would sit contemplatively before the statue of Maria Skłodowska which had been erected in 1935 before the Radium Institute that she had founded in 1932.

      At the beginning of 1890, Bronisława who a few months earlier had married Kazimierz Dłuski, a Polish physician and social and political activist — invited Maria to join them in Paris. Maria declined because she could not afford the university tuition; it would take her a year and a half longer to gather the necessary funds. She was helped by her father, who was able to secure a more lucrative position again. All that time she continued to educate herself, reading books, exchanging letters, and being tutored herself. In early 1889 she returned home to her father in Warsaw. She continued working as a governess, and remained there till late 1891.She tutored, studied at the Flying University, and began her practical scientific training (1890–91) in a chemical laboratory at the Museum of Industry and Agriculture at Krakowskie Przedmieście 66, near Warsaw's Old Town. The laboratory was run by her cousin Józef Boguski, who had been an assistant in Saint Petersburg to the Russian chemist Dmitri Mendeleev.

New life in Paris
     In late 1891, she left Poland for France. In Paris, Maria (or Marie, as she would be known in France) briefly found shelter with her sister and brother-in-law before renting a garret closer to the university, in the Latin Quarter, and proceeding with her studies of physics, chemistry, and mathematics at the University of Paris, where she enrolled in late 1891. She subsisted on her meager resources, suffering from cold winters and occasionally fainting from hunger.

    Marie studied during the day and tutored evenings, barely earning her keep. In 1893, she was awarded a degree in physics and began work in an industrial laboratory of Professor Gabriel Lippmann.Meanwhile, she continued studying at the University of Paris, and with the aid of a fellowship she was able to earn a second degree in 1894.

      Marie had begun her scientific career in Paris with an investigation of the magnetic properties of various steels, commissioned by The Society for the Encouragement of National Industry (Société d'encouragement pour l'industrie nationale. That same year Pierre Curie entered her life; it was their mutual interest in natural sciences that drew them together.Pierre was an instructor at the School of Physics and Chemistry, the École supérieure de physique et de chimie industrielles de la ville de Paris (ESPCI). They were introduced by the Polish physicist, Professor Józef Kowalski-Wierusz, who had learned that Marie was looking for a larger laboratory space, something that Kowalski-Wierusz thought Pierre had access to. Though Pierre did not have a large laboratory, he was able to find some space for Marie where she was able to begin work.

     Their mutual passion for science brought them increasingly closer, and they began to develop feelings for one another. Eventually Pierre proposed marriage, but at first Marie did not accept as she was still planning to go back to her native country. Pierre, however, declared that he was ready to move with her to Poland, even if it meant being reduced to teaching French. Meanwhile, for the 1894 summer break, Marie returned to Warsaw, where she visited her family. She was still laboring under the illusion that she would be able to work in her chosen field in Poland, but she was denied a place at Kraków University because she was a woman. A letter from Pierre convinced her to return to Paris to pursue a PhD. At Marie's insistence, Pierre had written up his research on magnetism and received his own doctorate in March 1895; he was also promoted to professor at the School. A contemporary quip would call Marie, "Pierre's biggest discovery." On 26 July 1895 they were married in Sceaux (Seine); neither wanted a religious service. Marie's dark blue outfit, worn instead of a bridal gown, would serve her for many years as a laboratory outfit. They shared two pastimes: long bicycle trips, and journeys abroad, which brought them even closer. In Pierre, Marie had found a new love, a partner, and a scientific collaborator on whom she could depend.

New elements
    In 1895, Wilhelm Roentgen discovered the existence of X-rays, though the mechanism behind their production was not yet understood. In 1896, Henri Becquerel discovered that uranium salts emitted rays that resembled X-rays in their penetrating power. He demonstrated that this radiation, unlike phosphorescence, did not depend on an external source of energy but seemed to arise spontaneously from uranium itself Influenced by these two important discoveries, Marie decided to look into uranium rays as a possible field of research for a thesis.

She used an innovative technique to investigate samples. Fifteen years earlier, her husband and his brother had developed a version of the electrometer, a sensitive device for measuring electric charge. Using Pierre's electrometer, she discovered that uranium rays caused the air around a sample to conduct electricity. Using this technique, her first result was the finding that the activity of the uranium compounds depended only on the quantity of uranium present. She hypothesized that the radiation was not the outcome of some interaction of molecules but must come from the atom itself. This hypothesis was an important step in disproving the ancient assumption that atoms were indivisible.

     In 1897, her daughter Irène was born. To support her family, Curie began teaching at the École Normale Supérieure.The Curies did not have a dedicated laboratory; most of their research was carried out in a converted shed next to the School of Physics and Chemistry. The shed, formerly a medical school dissecting room, was poorly ventilated and not even waterproof. They were unaware of the deleterious effects of radiation exposure attendant on their continued unprotected work with radioactive substances. The School did not sponsor her research, but she would receive subsidies from metallurgical and mining companies and from various organizations and governments.

Curie's systematic studies included two uranium minerals, pitchblende and torbernite (also known as chalcolite). Her electrometer showed that pitchblende was four times as active as uranium itself, and chalcolite twice as active. She concluded that, if her earlier results relating the quantity of uranium to its activity were correct, then these two minerals must contain small quantities of another substance that was far more active than uranium. She began a systematic search for additional substances that emit radiation, and by 1898 she discovered that the element thorium was also radioactive.

    Pierre was increasingly intrigued by her work. By mid-1898 he was so invested in it that he decided to drop his work on crystals and to join her.

   The idea  was her own; no one helped her formulate it, and although she took it to her husband for his opinion she clearly established her ownership of it. She later recorded the fact twice in her biography of her husband to ensure there was no chance whatever of any ambiguity. It  likely that already at this early stage of her career  realized that... many scientists would find it difficult to believe that a woman could be capable of the original work in which she was involved.

      She was acutely aware of the importance of promptly publishing her discoveries and thus establishing her priority. Had not Becquerel, two years earlier, presented his discovery to the Académie des Sciences the day after he made it, credit for the discovery of radioactivity, and even a Nobel Prize, would instead have gone to Silvanus Thompson. Curie chose the same rapid means of publication. Her paper, giving a brief and simple account of her work, was presented for her to the Académie on 12 April 1898 by her former professor, Gabriel Lippmann. Even so, just as Thompson had been beaten by Becquerel, so Curie was beaten in the race to tell of her discovery that thorium gives off rays in the same way as uranium; two months earlier, Gerhard Carl Schmidt had published his own finding in Berlin.

       At that time, no one else in the world of physics had noticed what Curie recorded in a sentence of her paper, describing how much greater were the activities of pitchblende and chalcolite than uranium itself: "The fact is very remarkable, and leads to the belief that these minerals may contain an element which is much more active than uranium." She later would recall how she felt "a passionate desire to verify this hypothesis as rapidly as possible." On 14 April 1898, the Curies optimistically weighed out a 100-gram sample of pitchblende and ground it with a pestle and mortar. They did not realize at the time that what they were searching for was present in such minute quantities that they would eventually have to process tons of the ore.

     In July 1898, Curie and her husband published a joint paper announcing the existence of an element which they named "polonium", in honour of her native Poland, which would for another twenty years remain partitioned among three empires. On 26 December 1898, the Curies announced the existence of a second element, which they named "radium", from the Latin word for "ray". In the course of their research, they also coined the word "radioactivity".

    To prove their discoveries beyond any doubt, the Curies sought to isolate polonium and radium in pure form. Pitchblende is a complex mineral; the chemical separation of its constituents was an arduous task. The discovery of polonium had been relatively easy; chemically it resembles the element bismuth, and polonium was the only bismuth-like substance in the ore. Radium, however, was more elusive; it is closely related chemically to barium, and pitchblende contains both elements. By 1898 the Curies had obtained traces of radium, but appreciable quantities, uncontaminated with barium, were still beyond reach. The Curies undertook the arduous task of separating out radium salt by differential crystallization. From a ton of pitchblende, one-tenth of a gram of radium chloride was separated in 1902. In 1910, Marie Curie isolated pure radium metal. She never succeeded in isolating polonium, which has a half-life of only 138 days.

     Between 1898 and 1902, the Curies published, jointly or separately, a total of 32 scientific papers, including one that announced that, when exposed to radium, diseased, tumor-forming cells were destroyed faster than healthy cells.

         In 1900, Curie became the first woman faculty member at the École Normale Supérieure, and her husband joined the faculty of the University of Paris. In 1902 she visited Poland on the occasion of her father's death.20In June 1903, supervised by Gabriel Lippmann, Curie was awarded her doctorate from the University of Paris. That month the couple were invited to the Royal Institution in London to give a speech on radioactivity; being a woman, she was prevented from speaking, and Pierre alone was allowed to. Meanwhile, a new industry began developing, based on radium. The Curies did not patent their discovery and benefited little from this increasingly profitable business.

Nobel Prizes
     In December 1903, the Royal Swedish Academy of Sciences awarded Pierre Curie, Marie Curie, and Henri Becquerel the Nobel Prize in Physics, "in recognition of the extraordinary services they have rendered by their joint researches on the radiation phenomena discovered by Professor Henri Becquerel." At first, the Committee intended to honour only Pierre and Becquerel, but one of the committee members and an advocate of woman scientists, Swedish mathematician Magnus Goesta Mittag-Leffler, alerted Pierre to the situation, and after his complaint, Marie's name was added to the nomination. Marie was the first woman to be awarded a Nobel Prize.

          Curie and her husband declined to go to Stockholm to receive the prize in person; they were too busy with their work, and Pierre, who disliked public ceremonies, was feeling increasingly ill. As Nobel laureates were required to deliver a lecture, the Curies finally undertook the trip in 1905. The award money allowed the Curies to hire their first laboratory assistant. Following the award of the Nobel Prize, and galvanized by an offer from the University of Geneva, which offered Pierre a position, the University of Paris gave Pierre a professorship and the chair of physics, although the Curies still did not have a proper laboratory. Upon Pierre's complaint, the University of Paris relented and agreed to furnish a new laboratory, but it would not be ready until 1906.

     In December 1904, Curie gave birth to their second daughter, Ève. She later hired Polish governesses to teach her daughters her native language, and sent or took them on visits to Poland.

    On 19 April 1906, Pierre was killed in a road accident. Walking across the Rue Dauphine in heavy rain, he was struck by a horse-drawn vehicle and fell under its wheels, causing his skull to fracture.Curie was devastated by her husband's death. On 13 May 1906 the physics department of the University of Paris decided to retain the chair that had been created for Pierre and to offer it to Marie.She accepted it hoping to create a world-class laboratory as a tribute to Pierre. She was the first woman to become a professor at the University of Paris.

      Curie's quest to create a new laboratory did not end with the University of Paris, however. In her later years, she headed the Radium Institute (Institut du radium, now Curie Institute, Institut Curie), a radioactivity laboratory created for her by the Pasteur Institute and the University of Paris. The initiative for creating the Radium Institute had come in 1909 from Pierre Paul Émile Roux, director of the Pasteur Institute, who had been disappointed that the University of Paris was not giving Curie a proper laboratory and had suggested that she move to the Pasteur Institute. Only then, with the threat of Curie leaving, did the University of Paris relent, and eventually the Curie Pavilion became a joint initiative of the University of Paris and the Pasteur Institute.In 1910 Curie succeeded in isolating radium; she also defined an international standard for radioactive emissions that was eventually named for her and Pierre: the curie.Nevertheless, in 1911 the French Academy of Sciences did not elect her to be a member by one or two votes.Elected instead was Édouard Branly, an inventor who had helped Guglielmo Marconi develop the wireless telegraph. A doctoral student of Curie, Marguerite Perey, became the first woman elected to membership in the Academy – over half a century later, in 1962. Despite Curie's fame as a scientist working for France, the public's attitude tended toward xenophobia—the same that had led to the Dreyfus affair–which also fuelled false speculation that Curie was Jewish. During the French Academy of Sciences elections, she was vilified by the right wing press who criticised her for being a foreigner and an atheist. Her daughter later remarked on the public hypocrisy as the French press often portrayed Curie as an unworthy foreigner when she was nominated for a French honour, but would portray her as a French hero when she received a foreign one such as her Nobel Prizes.

      In 1911 it was revealed that in 1910–11 Curie had conducted an affair of about a year's duration with physicist Paul Langevin, a former student of Pierre'sa married man who was estranged from his wife.This resulted in a press scandal that was exploited by her academic opponents. Curie (then in her mid-40s) was five years older than Langevin and was misrepresented in the tabloids as a foreign Jewish home-wrecker. When the scandal broke, she was away at a conference in Belgium; on her return, she found an angry mob in front of her house and had to seek refuge, with her daughters, in the home of a friend.[International recognition for her work had been growing to new heights, and the Royal Swedish Academy of Sciences, overcoming opposition prompted by the Langevin scandal, honored her a second time, with the 1911 Nobel Prize in Chemistry. This award was "in recognition of her services to the advancement of chemistry by the discovery of the elements radium and polonium, by the isolation of radium and the study of the nature and compounds of this remarkable element."She was the first person to win or share two Nobel Prizes, and remains alone with Linus Pauling as Nobel laureates in two fields each. A delegation of celebrated Polish men of learning, headed by novelist Henryk Sienkiewicz, encouraged her to return to Poland and continue her research in her native country. Curie's second Nobel Prize enabled her to persuade the French government into supporting the Radium Institute, built in 1914, where research was conducted in chemistry, physics, and medicine. A month after accepting her 1911 Nobel Prize, she was hospitalised with depression and a kidney ailment. For most of 1912 she avoided public life but did spend time in England with her friend and fellow physicist, Hertha Ayrton. She returned to her laboratory only in December, after a break of about 14 months.

    In 1912 the Warsaw Scientific Society offered her the directorship of a new laboratory in Warsaw but she declined, focusing on the developing Radium Institute to be completed in August 1914, and on a new street named Rue Pierre-Curie. She visited Poland in 1913 and was welcomed in Warsaw but the visit was mostly ignored by the Russian authorities. The Institute's development was interrupted by the coming war, as most researchers were drafted into the French Army, and it fully resumed its activities in 1919.

World War I
   During World War I, Curie saw a need for field radiological centres near the front lines to assist battlefield surgeons. After a quick study of radiology, anatomy, and automotive mechanics she procured X-ray equipment, vehicles, auxiliary generators, and developed mobile radiography units, which came to be popularly known as petites Curies ("Little Curies"). She became the director of the Red Cross Radiology Service and set up France's first military radiology centre, operational by late 1914. Assisted at first by a military doctor and by her 17-year-old daughter Irène, Curie directed the installation of 20 mobile radiological vehicles and another 200 radiological units at field hospitals in the first year of the war. Later, she began training other women as aides.

     In 1915 Curie produced hollow needles containing 'radium emanation', a colorless, radioactive gas given off by radium, later identified as radon, to be used for sterilizing infected tissue. She provided the radium from her own one-gram supply. It is estimated that over a million wounded soldiers were treated with her X-ray units. Busy with this work, she carried out very little scientific research during that period. In spite of all her humanitarian contributions to the French war effort, Curie never received any formal recognition of it from the French government.

     Also, promptly after the war started, she attempted to donate her gold Nobel Prize medals to the war effort but the French National Bank refused to accept them. She did buy war bonds, using her Nobel Prize money. She was also an active member in committees of Polonia in France dedicated to the Polish cause. After the war, she summarized her war time experiences in a book Radiology in War (1919).

Postwar years
      In 1920, for the 25th anniversary of the discovery of radium, the French government established a stipend for her; its previous recipient was Louis Pasteur (1822–95).[45] In 1921, Marie was welcomed triumphantly when she toured the United States to raise funds for research on radium. Mrs. William Brown Meloney, after interviewing Marie, created a Marie Curie Radium Fund and raised money to buy radium, publicising her trip. In 1921, US President Warren G. Harding received her at the White House to present her with the 1 gram of radium collected in the United States.Before the meeting, recognising her growing fame abroad, and embarrassed by the fact that she had no French official distinctions to wear in public, the French government offered her a Legion of Honour award, but she refused. In 1922 she became a fellow of the French Academy of Medicine. She also travelled to other countries, appearing publicly and giving lectures in Belgium, Brazil, Spain, and Czechoslovakia.

    Led by Curie, the Institute produced four more Nobel Prize winners, including her daughter Irène Joliot-Curie and her son-in-law, Frédéric Joliot-Curie. Eventually, it became one of four major radioactivity research laboratories, the others being the Cavendish Laboratory, with Ernest Rutherford; the Institute for Radium Research, Vienna, with Stefan Meyer; and the Kaiser Wilhelm Institute for Chemistry, with Otto Hahn and Lise Meitner.

    In August 1922, Marie Curie became a member of the newly created International Commission for Intellectual Cooperation of the League of Nations. In 1923, she wrote a biography of Pierre, entitled Pierre Curie. In 1925, she visited Poland, to participate in the ceremony that laid foundations for the Radium Institute in Warsaw. Her second American tour, in 1929, succeeded in equipping the Warsaw Radium Institute with radium; it was opened in 1932 and her sister Bronisława became its director.These distractions from her scientific labours and the attendant publicity caused her much discomfort but provided resources needed for her work. In 1930, she was elected a member of the International Atomic Weights Committee where she served until her death.

Death
       Curie visited Poland for the last time in early 1934. A few months later, on 4 July 1934, she died at the Sancellemoz Sanatorium in Passy, in Haute-Savoie, from aplastic anemia believed to have been contracted from her long-term exposure to radiation. The damaging effects of ionising radiation were not known at the time of her work, which had been carried out without the safety measures later developed. She had carried test tubes containing radioactive isotopes in her pocket, and she stored them in her desk drawer, remarking on the faint light that the substances gave off in the dark. Curie was also exposed to X-rays from unshielded equipment while serving as a radiologist in field hospitals during the war. Although her many decades of exposure to radiation caused chronic illnesses (including near blindness due to cataracts) and ultimately her death, she never really acknowledged the health risks of radiation exposure.

   She was interred at the cemetery in Sceaux, alongside her husband Pierre. Sixty years later, in 1995, in honour of their achievements, the remains of both were transferred to the Panthéon, Paris. She became the first woman to be honoured with interment in the Panthéon on her own merits. In 2015, two other women were also interred on their own merits.

    Because of their levels of radioactive contamination, her papers from the 1890s are considered too dangerous to handle. Even her cookbook is highly radioactive. Her papers are kept in lead-lined boxes, and those who wish to consult them must wear protective clothing.
In her last year, she worked on a book, Radioactivity, which was published posthumously in 1935.


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