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Marie Curie

Marie Curie

  The famous chemist and physicist, Marie Curie was the first person in the history to be awarded with       the two Nobel Prizes in diverse fields of science (chemistry and physics). She is notable for her theory of radioactivity, techniques for isolating radioactive isotopes, and the discovery of two new elements, polonium and radium. Her work has received great appreciation from many scientists all over the world.

Early Life

Marie Curie was born in Warsaw on November 7, 1867. She was the fifth and the youngest daughter of a secondary-school teacher. Her early years were very difficult with her mother and her sister passing away. She received her early education from some local school and her father taught her mathematics and physics, subjects that Marie was to pursue. She lived in Warsaw until she was twenty-four years old and later moved to Paris to receive higher education at the Sorbonne. There she obtained Licenciateships in Physics and the Mathematical Sciences.

In 1894, she met Pierre Curie, instructor in the School of Physics and Chemistry. Marie had begun her scientific career in Paris with an examination of the magnetic properties of various steels; it was their common interest in magnetism that brought Marie and Pierre together. The following year they got married.

Achievements

In 1896 when Henry Becquerel made his discovery of radio activity, the Curie’s became inspired to look into uranium rays as a possible field of research for a thesis. In 1898 their brilliant researches led to the discovery of polonium, named after the country of Marie’s birth, and radium. In 1903, the Royal Swedish Academy of Sciences honoured both Pierre Curie and Marie Curie with the Nobel Prize in Physics, for their joint researches on the radiation phenomena discovered by Becquerel.

Following the unfortunate death of her husband in 1906, she took his place as Professor of General Physics in the Faculty of Sciences. She was the first woman who had held this position. She was also employed as Director at the Curie Laboratory in the Radium Institute of the University of Paris, founded in 1914.

After her husband’s death she continued with her efforts of developing methods for obtaining pure radium from radioactive residues in sufficient quantities. By 1910, she successfully isolated the pure radium metal.

In 1911, Curie was awarded with yet another Nobel Prize, this time in Chemistry in recognition of her work in radioactivity.

All her life Marie promoted the use of radium and also set a great example of its use during World War I for healing the injuries of those who suffered. Her passion for science is reflected in all her efforts towards its advancement. She was also a member of the Conseil du Physique Solvay from 1911 until her death. Moreover since 1922 she had been a member of the Committee of Intellectual Co-operation of the League of Nations. In 1932 she also laid the foundation of Radium Institute (now the Maria Sk?odowska–Curie Institute of Oncology) in Warsaw. Her work is recorded in various papers in scientific journals

Death

The great scientist Marie Curie died on July 4, 1934 at the Sancellemoz Sanatorium in Passy, in Haute-Savoie from aplastic anemia.

Her name will always be written in golden letters for her tremendous contribution to the field of science.

Supercooled water can stay liquid far belowits normal freezing point

                                     

Very-sub-zero water

Supercooled water can stay liquid far below its normal freezing point

Cold water has hit a new low. Droplets can avoid freezing — at least for a short while — at

temperatures as low as –46° Celsius (–50.8° Fahrenheit), a new study shows.

“It’s a world record, and it’s hard to imagine it will ever fall,” H. Eugene Stanley told Science

News. This physicist at Boston University, in Massachusetts, did not take part in the new study.

Water's normal freezing point is 0° C (32° F). But under some conditions, even colder water can

remain liquid. It’s something scientists have long known. Such “supercooled” water stays liquid as

long as it doesn't touch anything, such as a dust particle or an ice cube tray. Once it does, it turns

to ice.

The previous record for supercooled water was -38° C (-36.4° F). However, scientists suspected

water could go colder still.

At really low temperatures, water’s behaviour turns quirky. Both its ability to absorb heat — and to

be squished — change at extreme lows.

“If you understand water there, you understand it everywhere,” Anders Nilsson told Science News.

He’s the new study’s leader. A physicist, he works at Stanford University and the SLAC National16/8/2014 Very-sub-zero water | Science News for Students

       Nilsson’s team used a small squirt gun to fire droplets of water into a vacuum chamber. The

droplets were as small as red blood cells. As each droplet sped through the chamber, some of its

molecules evaporated, or turned to gas. That process released heat. Each time this happened,

the droplet grew a bit colder.

Using a laser, the researchers fired X-ray pulses at the droplets. Those X-rays traveled right

through each droplet. By measuring changes in the X-ray pulses as they passed through a

droplet, the scientists could calculate the water’s temperature.

And a droplet’s temperature fell by as much as 10° C every millisecond, the tests showed. But the

drops could remain at the record low temp for only a millisecond. Then they turned to ice. The

scientists shared their findings June 19 in Nature.

The X-rays also destroyed each droplet as they took its temperature. “It’s like a hit-and-run,”

Nilsson explained to Science News.

Chemical engineer Pablo Debenedetti from Princeton University in New Jersey did not work on

the new study. He notes that the droplets remained liquid far longer than some researchers had

predicted. That’s why, he concludes, “It’s a major experimental accomplishment.”