Karl Manne Georg Siegbahn (Born 3 December 1886):
Swedish Physicist who was awarded the 1924 Nobel Prize in Physics for his seminal contributions to the development of X-ray spectroscopy. His studies built on the earlier work of Henry Moseley which had established the relationship between the wavelengths of X-rays emitted by some elements and their place in the periodic table. Siegbahn’s improved experimental apparatus enabled him to resolve new features and measure their wavelengths with unprecedented accuracy. He developed the socalled Siegbahn Notation (the well-known K, L, M series) for identifying the different characteristic X-ray spectral lines of particular elements, which are also now widely used in EDX analysis. He was appointed as the first Director of the Nobel Institute of Physics, which was established by the Swedish Royal Academy of Science. The Institute is now known as the Manne Siegbahn Institute (see Manne Siegbahn – Biographical (nobelprize.org), Siegbahn, Manne, 1886-1978 (aip.org), Manne Siegbahn – Wikipedia, Manne Siegbahn Biography – Childhood, Life Achievements & Timeline (thefamouspeople.com) and December 3 – Today in Science History – Scientists born on December 3rd, died, and events)).
Jean Servais Stas (Died 13 December 1891; born 21 August 1813):
Belgian chemist most noted for his accurate measurements of atomic weights. He initially accepted William Prouf’s hypothesis that the atomic weights of all elements were exact multiple of that of hydrogen, but his work ultimately led to this theory being rejected. His work established the foundations for the later development of the periodic table. He was widely recognised as the most skilful analytical chemist of the 19 th century (see Jean Servais Stas – Oxford Reference, Jean Servais Stas | Journal of Chemical Education (acs.org), JEAN-SERVAIS STAS Atomic mass of the elements, phlorizin, and toxicology (redalyc.org) and December 13 – Today in Science History – Scientists born on December 13th, died, and events).
Mariana Weissmann (Born 17 December 1933):
Argentine physicist whose work has explored the effects of disorder and non-periodicity in the properties of materials, including amorphous solids, surfaces, clusters, semiconductors, high T c superconductors, magnetic multilayers and fullerenes. In 2003, she became the first Argentine scientist to receive the L’Oréal-UNESCO Award for Women in Science (see Microsoft Word – seconda copertina.doc (ictp.it), About Mariana Weissmann: Argentinian physicist, specialized in computational physics (born: 1933) | Biography, Facts, Career, Life (peoplepill.com) and Mariana Weissmann – Wikipedia).
