Joliot, Pierre

Marie and Irene Curie, and their husbands, Pierre Curie and Frederic Joliot. Marie Curie (1867-1934) was born Maria Sklodowska in Warsaw, Poland, then a part of the Russian empire. In 1891 she emigrated to Paris to study at the Sorbonne, where she met and married a French physicist, Pierre Curie (1859-1906). The Curies were associates of Henri Becquerel, the man who discovered that uranium salts are radioactive. They showed that thorium, like uranium, is radioactive and that the amount of radiation emitted is directly proportional to the amount of uranium or thorium in the sample. 

The creation, by neutron bombardment of uranium, of the so-called transuraniums is based on the discovery of artificial radioactivity by M. and Mme. Joliot-Curie. Irene Curie was bom in Paris in September, 1897, the elder daughter of M. and Mme. Pierre Curie of honored memory. Both in Poland and in France she had many relatives who were devoting their lives to science, and from her earliest childhood she lived in a scientific atmosphere, among distinguished chemists and physicists. When Irene was less than a year old, her mother discovered the radioactive element polonium, which was destined to play an important part in the later researches of both mother and daughter. A few months later M. and Mme. Curie discovered another element of even greater importance, which they named radium. 

If the photosystem II reaction center transfers only one electron at a time, how does it assemble the four oxidizing equivalents needed for oxidation of H20 to 02 One possibility is that several different photosystem II reaction centers cooperate, but this seems not to happen. Instead, each reaction center progresses independently through a series of oxidation states, advancing to the next state each time it absorbs a photon. In this event 02 evolution would occur only when a reaction center has accumulated four oxidizing equivalents. Support for this conclusion comes from measurements made by Pierre Joliot of the amount of 02 evolved on each flash when chloroplasts are excited with a series of short flashes after a period of darkness. No 02 is released on the first or second flashes (fig. 15.21), but on the third flash, there is a burst of 02. After this, the amount of 02 released on each flash oscillates, going through a maximum every fourth flash. 

Pierre Joliot, Institute de Biologie Physico-Chimique, Fondation Edmond de Rothschild, Paris, France... 

Sometimes the nucleus can be changed by bombarding it with another type of particle. This is referred to as induced radioactivity. In 1934, Irene Curie, the daughter of Pierre and Marie Curie, and her husband, Frederic Joliot, announced the first synthesis of an artificial radioactive isotope. They bombarded a thin piece of aluminum foil with ot-particles produced by the decay of polonium and found that the aluminum target became radioactive. Chemical analysis showed that the product of this reaction was an isotope of phosphorus. 

About 30 years after the discovery of the electron, Irene Joliot-Curie (the daughter of the famous scientists Marie and Pierre Curie) discovered that when alpha particles hit a sample of beryllium, a beam that could go through almost anything was produced. 

Joliot-Curie, Irene (1897-1956) French Nuclear physicist Irene Curie was born in Paris on September 12, 1897, the daughter of the Nobel laureate physicists Pierre and Marie Curie. Growing up in the Curie family, Irene had no doubt that she would follow in her famous parents footsteps. First home-schooled, she finished high school at College Sevigne, an independent school in the center of Paris, and then received a baccalaureat from the same academy in 1914 and a doctorate of science from the Sorbonne in 1925 for her thesis on the alpha rays of polonium. She served in World War I as a nurse radiographer. After the war, she joined her mother as an assistant at the Institute of Radium. 

Marie Sklodowska Curie (1867-1934) is the only person to have been honored with Nobel Prizes in both physics and chemistry. In 1903, Pierre (1859-1906) and Marie Curie and Henri Becquerel (1852-1908) shared the prize in physics for the discovery of namral radioactivity. Marie Curie also received the 1911 Nobel Prize in chemistry for her discovery of radium and polonium and the compounds of radium. She named polonium for her native Poland. Marie s daughter, Irene JoUot-Curie (1897-1956), and Irene s husband, Frederick Joliot (1900-1958), received the 1935 Nobel Prize in chemistry for the first synthesis of a new radioactive element. 

Marie (Marya Sklodowska) Curie (1867-1934). Polish-born chemist and physicist. In 1903 she and her French husband, Pierre Curie, were awarded the Nobel Prize in Physics for their work on radioactivity. In 1911, she again received the Nobel prize, this time in chemistry, for her work on the radioactive elements radium and polonium. She is one of only three people to have received two Nobel prizes in science. Despite her great contribution to science, her nomination to the French Academy of Sciences in 1911 was rejected by one vote because she was a woman Her daughter Irene, and son-in-law Frederic Joliot-Curie, shared the Nobel Prize in Chemistry in 1935. 

Biquard, Pierre. 1962. Frederic Joliot-Curie. Paul S. Eriksson. 

In 1934, Irene Curie JoUot, daughter of Marie and Pierre Curie, and her husband, FredericJoliot, bombarded aluminum (Al) with alpha particles and observed neutrons and a positron. The Joliots discovered that when the flow of alpha particles striking the Al was stopped, the neutron emissions stopped, but the positron emissions continned. They reasoned that the alpha particles reacted with aluminum nuclei to produce phosphorus-30 nuclei, which then decayed to produce positrons. 

Joliot-Curie, Irene (1897-1956) French physicist, daughter of Marie and Pierre Curie, who was educated by her mother and her scientist associates. In 1921 she began work at the Radium Institute, becoming director in 1946. In 1926 she married Fr d ric Jollot (1900-58). They shared the 1935 Nobel... 

Irene Joliot-Curie (daughter of Pierre and Marie Curie) and her husband Frederic Joliot-Curie observed that when aluminum-27 is bombarded with alpha particles, neutrons and positrons (positive electrons) are emitted as part of the products. When the source of alpha particles is removed, neutrons cease to be produced, but positrons continue to be emitted. This observation suggested that the neutrons and positrons come from two separate reactions. It also indicated that a product of the first reaction is radioactive. After further investigation, they discovered that, when aluminum-27 is bombarded with alpha particles, phosphorus-30 and neutrons are produced. Phosphorus-30 is radioactive, has a half-life of 2.5 minutes, and decays to silicon-30 with the emission of a positron. The equations for these reactions are... 

In 1898, the Curies discovered a second new element that they called radium due to its extreme radioactivity. They wrote, The radioactivity of radium must be enormous. . . 900 times that of uranium. In fact, pure radium is so radioactive that it spontaneously glows. In 1903, Marie was awarded her Ph.D. and within a few months shared the Nobel Prize in physics with her husband Pierre and Henri Becquerel for the discovery of radioactivity. In 1911, Marie was awarded a second Nobel Prize, this time in chemistry, for her discovery of the two new elements radium and polonium. She was the first person to win two Nobel Prizes. As a further tribute to this amazing family, the Curies daughter, Irene, shared a Nobel Prize in physics in 1935 with her husband, Frederick Joliot, for her work in radioactivity. 

Pierre and Marie Curie shared the 1903 Nobel Prize in physics for their work explaining radioactivity that occurs naturally. Their daughter, Irene Joliot-Curie (1897-1956), and Irene s husband, Jean-Frederic Joliot-Curie (1900-1958), shared the 1935 Nobel Prize in chemistry for their discovery of radioactivity that can be induced artificially. 

The world press was initially captivated by the beautiful young Polish woman who shared the 1903 Nobel Prize in physics with Henri Becherel and Pierre Curie and she distributed the prize money to acquaintances and students. She and Pierre did not realize the effect that the radioactivity had on their health and in 1906 a weakened Pierre walked in front of a horse carriage and was killed. The Curies had two daughters before Pierre died and one daughter, Irene Joliot-Curie, was also awarded a Nobel Prize in chemistry in 1935 for discovering that aluminum became radioactive when bombarded with alpha particles. Note that the decay of radium can provide energetic... 

In 1934, when bombarding aluminum with a particles, Irene Joliot-Curie (daughter of Marie and Pierre Curie) and her husband, Frederic Joliot, observed the emission of two types of particles neutrons and positrons. The Joliots observed that when bombardment by a particles was stopped, the emission of neutrons also stopped the emission of positrons continued, however. Their conclusion was that the nuclear bombardment produces 15 P, which undergoes radioactive decay by the emission of positrons. 

---