Monday, April 25, 2011

Niels Bohr

Name : Niels Henrik David Bohr
Nationality : Danish
Birth of Date: 07/10/1885
Death : 18/11/1962
1922 Nobel Prize For Physics : For his services in the investigation of the structure atoms and of the radiation emanating from them.

Early years :  Bohr was born in Copenhagen , Denmark . He received a doctorate from Copenhagen University in 1911.
  His father, Christian Bohr, was professor of physiology at the University of Copenhagen (it is his name which is given to the Bohr shift or Bohr effect), while his mother, Ellen Adler Bohr, came from a wealthy Jewish family prominent in Danish banking and parliamentary circles. His brother was Harald Bohr, a mathematician and Olympic footballer who played on the Danish national team. Niels Bohr was a passionate footballer as well, and the two brothers played a number of matches for the Copenhagen-based Akademisk Boldklub, with Niels in goal. There is, however, no truth in the oft-repeated claim that Niels Bohr emulated his brother Harald by playing for the Danish national team.

In 1903 Bohr enrolled as an undergraduate at Copenhagen University, initially studying philosophy and mathematics. In 1905, prompted by a gold medal competition sponsored by the Royal Danish Academy of Sciences and Letters, he conducted a series of experiments to examine the properties of surface tension, using his father's laboratory in the university, familiar to him from assisting there since childhood. His essay won the prize, and it was this success that decided Bohr to abandon philosophy and adopt physics.[3] As a student under Christian Christiansen he received his doctorate in 1911. As a post-doctoral student, Bohr first conducted experiments under J. J. Thomson at Trinity College, Cambridge. In 1912 he joined Ernest Rutherford at Manchester University and he adapted Rutherford's nuclear structure to Max Planck's quantum theory and so obtained a theory of atomic structure which, with later improvements, mainly as a result of Heisenberg's concepts, remains valid to this day. On the basis of Rutherford's theories, Bohr published his model of atomic structure in 1913, introducing the theory of electrons traveling in orbits around the atom's nucleus, the chemical properties of the element being largely determined by the number of electrons in the outer orbits. Bohr introduced the idea that an electron could drop from a higher-energy orbit to a lower one, emitting a photon (light quantum) of discrete energy. This became a basis for quantum theory. After four productive years with Ernest Rutherford in Manchester, Bohr returned to Denmark becoming in 1918 director of the newly created Institute of Theoretical Physics.

Bohr and his wife Margrethe Nørlund Bohr had six sons. Their oldest died in a tragic boating accident and another died from childhood meningitis. The others went on to lead successful lives, including Aage Bohr, who became a very successful physicist and, like his father, won a Nobel Prize in physics, in 1975.

Monday, April 11, 2011

Scientist Ranking

  1. Issac Newton
  2. Albert Einstein 
  3. Neils Bohr
  4. Charles Darwin
  5. Louis Pasteur
  6. Sigmund Freud
  7. Galileo Galilei
  8. Antoine Laurent Lavoisier
  9. Johannes Kepler
  10. Nicolaus Copernicus 
  11. Michael Faraday
  12. James Clark Maxwell
  13. Claude Bernard
  14. Franz Boas
  15. Werner Heisenberg
  16. Linus Pauling
  17. Rudolf Virchow
  18. Erwin Schrodinger
  19. Earnest Rutherford
  20. Paul Dirac
  21. Andreas Vesalius
  22. Tycho Brahe
  23. Comte de Buffon
  24. Ludwig Boltzman
  25. Max Planck
  26. Marie Curie
  27. William Herschel
  28. Charles Lyell
  29. Pierre Simon de Laplace
  30. Edwin Hubble
  31. Joseph J. Thomson
  32. Max Born
  33. Francis Crick
  34. Enrico Fermi
  35. Leonard Euler
  36. Justus Liebig
  37. Arthur Eddington
  38. William Harvey
  39. Marcello Malpighi
  40. Christiaan Huygens
  41. Carl Gauss
  42. Albrecht von Haller
  43. August Kekule
  44. Robert Koch
  45. Murray Gell-Mann
  46.  Emil Fischer
  47. Demitri Mendeleev
  48. Sheldon Glashow
  49. James Watson
  50. John Bardeen
  51. John von Neumann
  52. Richard Feynman
  53. Alfred Wegener
  54.  Stephen Hawking
  55. Anton van Leeuwenhoek
  56. Max von Laue
  57. Gustav Kichoff
  58. Hans Bethe
  59. Euclid
  60. Gregor Mendel
  61. Heike Kamerlingh Onnes
  62. Thomas Hunt Morgan
  63. Harmann von Helmholtz
  64. Paul Ehrlich 
  65. Ernst Mayr
  66. Charles Shernington
  67. Theodosius Dobzhansky
  68.  Max Delbruck
  69. Jean Baptiste Lamarck
  70. William Bayliss
  71. Noam Chomsky
  72. Frederick Sanger
  73. Lucretius
  74. John Dalton
  75. Louis Victor de Broglie
  76. Carl Linnaeus
  77. Jean Piaget
  78. George Gaylord Simpson
  79. Claude Levi-Strauss
  80. Lynn Margulis
  81. Karl Landsteiner
  82. Konrad Lorenz
  83. Edward O. Wilson
  84. Frederick Gowland Hopkins
  85. Gertrude Belle Elion
  86. Hans Selye
  87. J. Robert Oppenheimer
  88. Edward Teller
  89. Willard Libby
  90. Ernst Haeckel
  91. Jonas Salk
  92.  Emil Kraepelin
  93. Trofim Lysenko
  94. Francis Galton
  95. Alfred  Binet
  96. Alfred Kinsey
  97. Alexander Fleming
  98. B.F.Skinner
  99. Wilhelm Wundt
  100. Archimedes