Sunday, December 30, 2012

John Bahcall

John Norris Bahcall was born on December 30, 1934 in Shreveport, Louisiana. His mother, Mildred, was a pianist and both she and his father, Malcolm Bahcall, worked in a family business. He did not take any science classes in high school because he was excused to play tennis in the afternoons and he went to the Louisiana State University in Baton Rouge, Louisiana on a tennis scholarship, where he studied philosophy with the goal of becoming a rabbi. After a year he transferred to the University of California Berkeley, still studying philosophy. At Berkeley he took his first physics class as a graduation requirement. He graduated with a A.B. physics, from UCB in 1956. He earned his M.S. in physics from the University of Chicago and his Ph.D. in physics from Harvard University in 1961. He became a research fellow in physics at the University of Indiana in 1961 and worked at the California Institute of Technology from 1962 to 1970. He was appointed professor of physics at the Institute for Advanced Study in Princeton, New Jersey in 1971, where he remained the rest of his career.

Bahcall's field was astrophysics. He worked on many problems in astrophysics, but he is most remembered for his work on stellar neutrinos. Stars produce energy by a series of different nuclear reactions converting hydrogen to helium. One of the products of these reactions are electron-neutrinos. Neutrinos are neutral subatomic particles and come in three "flavors", electron-neutrinos, muon-neutrinos and tau-neutrinos. Because they do not have a charge, they do not interact with other substances and generally pass directly through. It has been estimated that every centimeter of the earth, exposed to direct sunlight, has 65 billion neutrinos pass through it per second. To detect the neutrinos as they pass through the earth Bahcall, working with Raymond Davis Jr., did the theoretical calculations for a detector that was built in the Homestake Gold Mine in Lead, South Dakota, using a 380 cubic meter tank filled with dry cleaning fluid (tetrachloroethylene). The chlorine atoms in  the dry cleaning fluid are transformed into argon when they are hit by an electron-neutrino. The argon is collected and the amount of electron-neutrinos hitting the tank can be counted. The initial results of the experiment, announced in 1968, found only one third of the amount of neutrinos predicted by theory. For thirty years Bahcall worked on the problem and it was eventually determined that some of the neutrinos change from electron-neutrinos into muon- and tau-neutrinos and were not detected by the chlorine in Bahcall and Davis' experiment.

Bahcall won many honors during his career, including the Comstock prize in physics from the National Academy of Science and the Gold Medal from the Royal Academy of Science. He is also responsible, with Lyman Spitzer Jr., for designing the Hubble Space Telescope put into orbit in 1990. In 1992 he received NASA's Public Service Medal for this work. Bahcall also worked on understanding how our galaxy is put together and the current model of our galaxy, with a super-massive black hole at its center, is called the Bahcall-Wolfe model.

Bahcall died on August 17, 2005.


References:

Striker, Jeremiah P. and Bahcall, Neta A.; "John Norris Bahcall: 1934-2005"; Bulletin of the American Astronomical Society (2007)39:1053-4

Tremaine, Scott D.; "John Norris Bahcall: 1934-2005"; National Academy Press; 2011

John N. Bahcall Wikipedia Entry

Sunday, December 23, 2012

Niels Jerne

Niels Kaj Jerne was born on December 23, 1911 in London, England. His family had lived on the Danish island Fano since the seventeenth century. His father, Hans Jerne and mother, Else Lindberg, moved to London, England in 1910, the year before his birth. During the World War I the family lived in Rotterdam, Netherlands, where he spent his youth and earned his bachelors degree in 1928. After spending two years studying physics in Lieden, he moved to Copenhagen where he studied medicine, earning a medical degree in 1947 and a doctorate in 1951.

From 1943 to 1956 Jerne worked at the Danish National Serum Institute. During this time he proposed the theory of antibody selection, that the immune system produced a multitude of antibodies and through interactions with antigen (a molecule recognized by antibodies) antibodies were selected and the immune system produced more of them. This theory was later refined by David Talmadge and Frank Macfarlane Burnet, who separately proposed the genetic mechanism by which antibody producing cells each pick the DNA that will code for the cell's antibodies. Antibody producing cells are part of the body's humoral immune response. Antibodies are protein molecules that recognize and bind a particular antigen. Because they have multiple binding sites antibodies, when bound to antigen, can form large clumps. In a addition to their binding sites, antibodies have a site recognized by phagocytic cells. When large clumps of antibody/antigen complex form these recognition sites serve to signal phagocytic cells to devour it.

Starting in 1956 Jerne worked for the World Health Organization in Geneva. In 1962 he moved to the University of Pittsburg in Pittsburgh, Pennsylvania. From 1966 to 1969 he was director of the Paul-Erlich Institute and from 1969 to his retirement in 1980 he ran his own institute as director of the Basel Institute of Immunology. While there Jerne was the first to speculate about the role of the major histocompatability complex. This is a protein complex produced by cells that presents antigens on the cells surface. This is recognized by T-lymphocytes. When the antigen is recognized it means that it is foreign to the body and stimulates an immune response from the T-cell. T-cells then activate and secrete chemicals to stimulate the immune response.

Jerne's other major contribution to immunology was the idea that the immune system functions as a network, each part influencing the others. This is how the immune system is viewed today, where immune cells secrete an array of cytokines, hormones that influence the functions of the other cells of the body and the immune system. This paradigm has allowed immunologists to better understand immune cell dysfunction and the effects of the viral infection of immune cells in HIV infection. For his contributions to our understanding of immunology Jerne was awarded the 1984 Nobel Prize in Medicine, with Georges Kohler and Cesar Milstein.

Jerned died on October 7, 1994.


References:

Hoffmann, Geoffrey, W.; "Niels Jerne, Immunologist: 1911-1994"; Vaccine Research (1994)3

Nobel autobiography

Neils Gerne Wikipedia entry


Monday, December 17, 2012

Johann Ritter

Johann Wilhelm Ritter was born on December 16, 1776 in Samitz, Purssia, which is now part of Poland. At age 14 he was apprenticed to an apothecary in Liegnitz. In his studies he acquired and interest in chemistry. After inheriting money he was able to attend the University of Jena where he studied medicine starting in 1796. He remained at the university in a teaching position after his graduation. In 1802 the Duke o f Saxe-Gotha became his patron.

Ritter's early research involved using the method of Luigi Galvani, using frog legs as an indicator of electrical current. Using a method involving two frog legs Ritter measured the activity series of metals. Ritter's explanation for the effect was closest to what we know today to be a chemical reaction where electrons are transferred from one chemical to another. These are called redox reactions because two processes are taking place, oxidation (where electrons are removed from a chemical) and reduction (where electrons are added to a chemical). For this Ritter is referred to as the father of electrochemistry. Ritter was also the first to separate the oxygen and hydrogen produced by the electrolysis of water. When an electrical current is run through water, water decomposes in to oxygen and hydrogen gases.

Ritter is most famous for his discovery of ultraviolet radiation. After William Herschel announced the discovery of infra-red radiation in 1801 Ritter believed that there was also radiation on the other end of the visible spectrum. Using silver nitrate he tested different colors of light and found that violet light caused more decomposition than red light. He also found that the greatest decomposition occurred using a wavelength of light that could not be seen. This is what today we call ultraviolet light. It is the region of the electromagnetic spectrum between visible light and x-ray radiation, with a wavelength between 4000 and 10 angstroms.

In addition to his scientific activities Ritter was also active in the German romantic movement. Because of his belief in the occult and reluctance to publish his results he was disregarded by most of his contemporaries. Beset by financial difficulties he died at the age of 33 on January 23, 1810.


References:

Berg, Hermann; "Johann Wilhelm Ritter: the Founder of Scientific Electrochemistry"; Review of Polarography (2008)54:99-103

Davidson, Michael W., "Johann Wilhelm Ritter (1776-1810)"; retrieved from micro.magnet.fsu.edu

Johann Wilhelm Ritter Wikipedia Entry

Monday, December 10, 2012

Henry Kendall

Henry Way Kendall was born on December 9, 1926 in Boston, Massachusetts. His father was an industrialist and he had two siblings, a younger brother and sister. He grew up in Sharon, Massachusetts and attended Deerfield Academy in Deerfield, Massachusetts, graduating in 1945. As a child he had an intense curiosity for things mechanical, chemical and electrical. He attended the United States Merchant Marine Academy, and served on a troop transport ship in the north Atlantic during the winter of 1945-46. With the end of the World War II he enrolled in Amherst College, graduating with a bachelors in mathematics in 1950. After graduation he went to the Massachusetts Institute of technology where he earned his Ph.D. in physics. He did post-doctoral work at M.I.T. and Stanford university then returned to M.I.T. as a faculty member.

Kendall's research involved using particle accelerators to probe the make up of the atom. In the 1960s and 70s Kendall worked with Jerome Friedman and Richard Taylor scattering electrons off of protons, neutrons, duterons and other heavier nuclei. These experiments confirmed the existence of quarks, small, sub-nuclear particles that protons and neutrons are made of. Quarks take their name from a line in Finnegan's Wake by James Joyce, and come in two kinds, up quarks and down quarks. Protons are made up of two up quarks and one down quark and neutrons are made up of two down quarks and one up quark. For their work confirming the existence of quarks Kendall, Friedman, and Taylor were awarded the 1990 Nobel Prize in physics.

In a addition to his work in physics, Kendall was also an avid outdoorsman, mountain climber and scuba diver. In the 1960s Kendall served as an adviser to the United States Department of Defense. In 1969 he co-founded the Union of Concerned Scientists and served for many years as its chairman. The Union of Concerned Scientists is a non-profit group that advocates sensible environmental and sustainable agricultural policies. He was elected to the National Academy of Sciences in 1977 and was inducted into the American Alpine Club's Hall of Mountaineering Excellence in 2012.

He died on February 15, 1999 as the result of a scuba diving accident while exploring an underwater cave in Wakulla Springs State Park in Florida.


References:

Bjorken, James D., Friedman, Jerome I., Taylor, Gottfried, Kurt and Taylor, Richard B.; "Henry Way Kendal: 1926-1999"; National Academy Press; 2009

Kendall, Henry W., Nobel Autobiography

Kendall, Henry W. and Aasserud, Finn; "Oral History Transcript - Dr. Henry Kendall"; accessed at aip.org.

 Henry Way Kendall Wikipedia Entry

Sunday, December 2, 2012

George Minot

George Richards Minot was born on December 2, 1885 in Boston Massachusetts. Minot came from a Boston medical family (his great-grandfather, James Jackson, was co-founder of Massachusetts General Hospital) and after private schooling and graduating from Harvard College in 1908 he entered Harvard Medical School, graduating in 1912. In medical school he became interested in hematology and the diseases of the blood, although his first publication was on butterflies in 1902. As an intern he studied the effect of a patient's diet on their blood cells. In 1914 he took a job as an assistant at Johns Hopkins University in Baltimore, Maryland. In 1915 he returned to Boston as an assistant at Massachusetts General Hospital.

In 1922 he became physician-in-chief of Collis P. Huntington Memorial Hospital and in 1928 he became a professor of medicine at Harvard University. Minot published papers on many subjects, including vitamin B deficiency, blood coagulation, arthritis, leukemia, industrial blood poisoning, among others.

In 1914 he became interested in the work of George Whipple. Whipple was studying the effect of diet on anemic dogs and discovered that feeding dogs liver reversed the anemia. Minot, working with William Murphy of Johns Hopkins University, discovered that a diet of liver helped patients with pernicious anemia, a form of anemia characterized by improper red blood cell development. Later, working with William Cohn, he showed which fractions of the liver helped patients with pernicious anemia. Today it is known that pernicious anemia is caused by a deficit of vitamin B-12 or cobalamine. Vitamin B-12 is the only one of the B vitamins that contains an atom of the metallic element cobalt and it is involved in the DNA synthesis of developing red blood cells. For their discovery Whipple, Murphy and Minot were awarded the 1934 Nobel Prize in Medicine.

Minot died on February 15, 1950.

References:

Castle, W.B.; "George Richards Minot: 1885-1950"; National Academy Press; 1974

George Minot Wikipedia Entry

George Minot Nobel Biography

Sunday, November 25, 2012

Lewis Morris Rutherford

Lewis Morris Rutherford was born on November 25, 1816 in Morrisania, New York. He was named for his great-grandfather, Lewis Morris, one of the signers of the American Declaration of Independence. He began attending Williams College as a sophomore, at age 15. While an undergrad he studied natural sciences, including chemistry and finding pieces of a telescope in a storage closet, he manufactured the missing pieces and put it back together. After graduating in 1834 he studied law and passed the bar in 1837. He practiced law until 1849, when he built an observatory on the lawn of his house, which was called the finest private observatory in the country.

Rutherford used his 11 and 1/4 inch telescope to take pictures of the moon, the planets and stars. Then using a diffraction grating of his own manufacture he began taking spectra of planets and stars. In 1863 he published a paper which was the first attempt to classify stars according to their spectra, dividing stars into three categories. Today, most stars are classified using the system developed by Annie Jump Cannon that classifies stars by their color. In order of decreasing surface temperature, O are blue stars, B white/blue stars, A white stars, F yellow/white stars, G yellow stars, K orange stars, and M red stars.

Rutherford served as an trustee of Columbia University from from 1858 to 1884. He was an active participant in the International Meridian Conference which established the prime meridian as the line of longitude that runs through Greenwich, England. In 1867 he served as president of the American Photographical Society. He was an associate of the Royal Astronomical Society and a member of the National Academy of Sciences since its founding in 1863.

In his later years he was in delicate health and he died from the complications of a cold he contracted while traveling to his winter residence in Florida on May 30, 1892.

References:

Anon; "A Sketch of Lewis Morris Rutherford", Popular Science (1893) Vol. 42

Gould, B.A.; "Memoir of Lewis Morris Rutherford: 1816-1892"; National Academy Press; 1895

Lewis Morris Rutherford Wikipedia Entry

Sunday, November 18, 2012

Patrick Blackett, Baron Blackett


Patick Maynard Stuart Blackett was born on November 18, 1897 in Kensington, London. His father Arthur Blackett was a stockbroker and he had two sisters, one older and one younger than him. Starting at the age of nine he attended Allen House preparatory school. During his youth he used a wooden shed in the family garden to make crystal radios and model airplanes. In 1910, just before he turned 13, Blackett began attending Osborne Naval College on the Isle of Wight where he began his training as a naval officer. In 1912 he began studying at Britannia Royal Naval College in Dartmouth. in 1914, with the outbreak of World War I, Blackett served on the HMS Carnarvon which took part in the Battle of the Falkland Islands and he served aboard the HMS Barham which took part in the Battle of Jutland. In 1918, with the conclusion of the war he resigned from the Royal Navy as a lieutenant and went to study mathematics and physics at Magdalene College, Cambridge, where he worked under Ernest Rutherford in the Cavendish Laboratory.

Blackett graduated from Magdalene College with a B.A. in 1921 and continued working for Rutherford for another ten years. In 1923 he became a fellow at Kings College and in 1924 he used a cloud chamber to record the transmutation of nitrogen into oxygen. A cloud chamber is a closed chamber saturated with water or alcohol vapor. When ionizing particles (alpha particles for example) are introduced they create ions. The vapor in the chamber condenses on these ions and the condensed liquid shows the path of the particle through the chamber. While in the Cavendish Laboratory Blackett used a cloud chamber to do experiements involving cosmic rays. From 1924 to 1925 he worked in the laboratories of James Franck in Gottingen, Germany studying atomic spectra. In 1932, working with Italian physicist Giuseppe Occhialini, he developed a cloud chamber with a geiger counter to trigger the camera.

In 1933 he became professor at Birkback College, at the University of London. Also in 1933 he confirmed Carl David Anderson's discovery of the positron. A positron is a positively charged electron, an anti-matter particle. Blackett also worked on annihilation, the collision of matter and anti-matter that produces gamma radiation. In 1937 he became the Longworthy professor at Victoria University in Manchester. While there he worked on a theory of the earth magnetism, hoping to use it to unify the forces of gravity and magnetism. Although he was unsuccessful his work led to the development of paleomagnetism, which was used to prove the existence of continental drift.

In 1935 he was invited to serve on the Tizard Committee, which recommended the installation of radar for air defense. During World War II he served on various defense committees and contributed to the invention of the Mark XIV bomb sight. In 1940 he was awarded the Royal Medal by the Royal Society. In 1948 he was awarded the Nobel Prize for his work on particle physics using cloud chambers. He was appointed chairman of the physics department of Imperial College at London in 1953 and he retired in 1963. Blackett served as an adviser to the post war Labor government and in 1964, at his advice, set up the Ministry of Science and Technology. Blackett was outspoken politically and frequently came under criticism for his socialist and anti-nuclear weapon views.

He died on July 13, 1974.


References:

Brown, Matt; "Patrick Blackett: From Cosmic Rays to International Development"; November 18, 2007; London Blog at blogs.nature.com

Nye, Mary Jo; Blackett: Physics, War and Politics in the 20th Century; Harvard University Press; 2004

Patrick Blackett Nobel Biography

Patrick Blackett Wikipedia Entry

Sunday, November 11, 2012

Vesto Slipher

Vesto Melvin Slipher was born on November 11, 1875 at a farm in Mulberry, Indiana. His younger brother Earl was also an astronomer. He graduated from high school in Frankfort, Indiana and taught briefly at a country school before going to the University of Indiana in Bloomington, Indiana starting in 1897. He earned his bachelors degree in astronomy and mechanics in 1901. He earned his masters in 1903 and his doctorate in 1909 with a dissertation on the spectrum of Mars. One of his professors, Wilbur Cogshall, recommended him to Percival Lowell and Lowell brought Slipher on as an assistant in 1901. Slipher remained at the observatory for fifty three years afterward. He became assistant director in 1915 and became acting director in 1916 with Lowell's death. He became director in 1926 and served there until his retirement in 1954.

Slipher's first project, at the direction of Lowell, writing from his Boston office, was mounting and using the new spectrograph on Lowell's 24-inch refracting telescope. Slipher used it to record the spectra of Mars, Jupiter, and Saturn. Using the spectra that Slipher produced the confirmed the visually known periods of the planets. Using spectra taken of Mars, he attempted to prove there was water in the Martian atmosphere and he attempted to find the rotational period of Venus. He then turned the telescope to the gas giants and determined that the rotational period of Uranus was 10.75 hrs (it was later determined to be 25 hrs.).

Slipher is remembered chiefly for the work that he did determining the velocity of what at the time where called spiral nebula. Today we know these spiral shaped clouds are galaxies, just like our Milky Way. Slipher determined that these spiral nebula were moving much faster (three times) the velocity of any object observed at that time. Edwin Hubble later used this data to show the universe was expanding and the farther an object was away from Earth, the faster it would be moving away. Slipher is also responsible for hiring Clyde Tombaugh and was responsible for overseeing the work involved in the discovery of Pluto.

Awards won by Slipher include the Bruce Medal (1935), the Lalande Prize (1919), a Gold Medal from the Royal Society (1932), the Henry Draper Prize from the National Academy of Sciences (1932) and a gold medal from the Paris Academy of Sciences (1919). Slipher also has a crater on the moon named after him. In addition to his scientific work Slipher was also active in the community of Flagstaff, Arizona, where he was one of the founders of  its first high school.

Slipher died on November 8, 1969, in Flagstaff, Arizona.


References:

Hoyt, Willliam Graves, "Vesto Melvin Slipher: 1875-1969"; National Academy Press, 1980

Trimble, Virginia; Williams, Thomas; Bracher, Katherine; Jarrell, Richard; Marche, Jordan; and Ragep, F. Jamil; "Vesto Slipher" in Biographical Encyclopedia of Astronomers; Springer; 2006

Vesto Sipher Wikipedia Entry

Sunday, October 14, 2012

Sir Edward Sabine

Edward Sabine was born on October 14, 1788 in Dublin, Ireland. He was the fifth son and ninth child of Joseph Sabine and Sarah Sabine nee Hunt. Sabine's mother died one month after his birth. He obtained a military education first at Marlowe and then at Royal Military Academy at Woolrich. He was commissioned as an artillery officer in 1803, becoming a captain ten years later, and he rose to the rank of general in 1870. Sabine was stationed at Gibraltar during the Peninsular War and saw his first action during the War of 1812. On his voyage to Canada the ship he was on was captured by an American privateer. The ship was eventually recaptured by a British frigate and he made his way to Quebec. Sabine served in the Niagara campaign and took part in the siege and assault on Fort Eire, serving with distinction.

He returned to England in 1816 and began doing research in astronomy, terrestrial magnetism, and ornithology. He became a member of the Royal Society in 1818. Also in 1818 Sabine served as astronomer during the Ross expedition looking for the Northwest Passage. During the expedition Sabine took magnetic readings of the Earth and studied birds, identifying a new species (Larus sabini). The following year Sabine took part in another Northwest Passage expedition, this time under William Perry. The expedition was the first to make it north of the arctic circle, returning in 1820. In 1921 Sabine received the Copley Medal for his various researches during this expedition.

For the next couple years Sabine toured the world taking measurements with his pendulum. The period of a pendulum depends on its length and the force of gravity on the bob at the end of the string or arm. Because Earth is not a perfect sphere (it is an oblate sphere which bulges at the equator) the distance to the center of the Earth is not uniform at different latitudes. This causes the gravity at the earth surface to vary at different latitudes with the acceleration of gravity rising as you move toward the poles. The period of Sabine's pendulum, swung at different latitudes, differed due to the differences in gravity caused by the differences in the distance to the center of the Earth. With this experiment Sabine demonstrated that the earth is not perfectly spherical. For this work Sabine was honored with the Lalande Medal of the Institute of France in 1826

When the British Board of Longitude was abolished in 1828, Sabine, with Michael Farady and Thomas Young, was appointed as a scientific adviser to the Admiralty. In this position Sabine advocated for the creation of magnetic measuring stations throughout the British Empire. Because changes in the Earth's magnetic field, which at the time were believed to be the result of weather patterns, affected compass readings these magnetic observatories were built. The observations from these observatories were collated by Sabine in London and he discovered that changes in the Earth's magnetic field were due to sunspot activity and the influence of the moon.

Sabine won a gold medal from the Royal Society in 1849 and served as its president from 1861 to 1871. Sabine was knighted in 1864 and has a crater on the moon named after him. The California grey pine (Pinus sabineana) is also named after him.

He died on June 26, 1883 and was buried in his family vault in Tewin, Hertfordshire.


References:

Anon.; "Sir Edward Sabine"; The Observatory (1883)6:232-233

Vetch, Robert Hamilton; "Sabine, sir Edward"; Dictionary of National Biography, 1885-1900, Volume 50;

Edward Sabine Wikipedia Entry

Sunday, October 7, 2012

Rudolf Leuckart

Karl Georg Friedrich Rudolf Leuckart was born on October 7, 1822 in Helmstedt, Lower Saxony, which would later become part of Germany. His father owned a printing plant and his uncle, Friedrich Sigismund Leuckart, was a professor of zoology. His uncle awakened the interest in zoology in his young nephew, who collected insects. Leuckart was interested in pursuing a career in zoology, but a the time there were no university programs devoted to it, so he was forced to study medicine, which he did at the University of Gottingen starting in 1842. At Gottingen Leuckart met zoologist Rudolf Wagner and became his assistant in 1845. Leuckart's dissertation, the same year, won a university prize. Leuckard became a zoology lecturer and in 1848 he went on his first expedition to the North Sea to study marine microorganisms.

In 1850 Leuckart became professor of zoology at the University of Giessen. The years at Giessen were productive for Leuckart and he did a lot of the work studying parasites. He proved that cattle were the carrier of beef tape worm (Taenia saginata) and that pigs were the carriers of pork tapeworm (Taenia solium). Most vertebrate species have a tapeworm species that has evolved to live in its intestines. His studies of Trichina, the cause of trichinosis was used by Rudolf Virchow's campaign for meat inspection laws in Germany. With Virchow and Friedrich Albert von Zenker, he was the first to document the life cycle of Trichnella spiralis. For his work on parasites Leuckart is known as the father of parasitology. He also studied insects, documenting the anatomy and life cycle of the honey bee and the life cycle of Hippoboscoidea, (called Pupipara at the time) a super-family of obligate blood parasites that includes tsetse flies and bat flies.

In 1861 he was named a privy councilor by the King of Saxony and was awarded an honorary PhD by University of Giessen. In 1869 he moved to the University of Leipzig. At first the facilities were inadequate, but in 1880 a zoological institute was built according to his specifications. It quickly became a center for zoological learning and attracted students from around the world. While at Giessen he created a series of zoological posters showing  species of invertebrates that have been used world wide as teaching aids. Leuckart's magnum opus, a two volume work on human parasites and the diseases they cause remained unfinished at the time of his death but was still widely used by students of parisitology.

 Leuckart died in Leipzig on February 6, 1898.


References:

Kellog, Vernon L.;"Rudolf Leuckart"; Psyche (1898)8:214-215

"Leuckart, Karl Friedrich Rudolph"; in The Complete Dictionary of Scientific Biography; Charles Scribner's Sons; 2008

Rudolph Leuckart Wikipedia Entry

Sunday, September 30, 2012

Jean Perrin

Jean Baptiste Perrin was born on September 30, 1870 in Lille, France. He attended Ecole Normale Superieure in Lille and worked there as a physics assistant from 1894 to 1897. He earned his doctorate in 1897 for a thesis on cathode and x-rays. After graduation he was appointed to a readership in physical chemistry at the Sorbonne, University of Paris. He became a professor there in 1910. He served as an officer in the French Army's Engineering Corp. during the World War I and he was removed from his professorship when the Germans occupied Paris in 1940.

Perrin's early work on cathode rays proved that they were made of  negatively charged particles. His work covered a number of topics in physics including the effects of x-rays on the conductivity of gasses, fluorescence, and the radioactive disintegration of radium. He suggested that stars obtained their energy from the thermonuclear reactions of hydrogen. He wrote numerous books and papers including Les Atomes where he describes his studies on Brownian motion, which confirmed the atomic theory, that all matter is made of atoms.

In 1905 Albert Einstein had published a paper on Brownian motion describing how it was the result of atomic theory. Brownian motion is the random motion of particles suspended in a liquid, discovered in 1827 by Robert Brown, an English botanist who watched pollen particles suspended in water. Suspended in a liquid, the particles are constantly bombarded by moving molecules of the liquid. This causes the visible particles to move in random directions. Einstein's paper was theory and it was Perrin who experimentally demonstrated that matter is made of molecules. Perrin was able to use Brownian motion to determine a value for Avagadro's constant that closely agreed with the value obtained using Dalton's law of molecular motion. Avagadro's constant is the number of molecules in a mole of a substance. For his work, proving the atomic theory Perrin was awarded the 1926 Nobel Prize for Physics.

Perrin was the recipient of numerous other awards, including the Joule Prize from the Royal Society in 1896 and the La Caze Prize from the Paris Academy of Sciences in 1914. He was made a commander in the French Legion of Honor in 1926 and a commander in the Legion of Leopold (Belgium). He was awarded numerous honorary doctorates.

In 1940 he fled German occupied France to the United States where he died on April 17, 1942. After World War II, in 1948, his remains were returned to France aboard the light cruiser Jeanne d'Arc and he was buried in the Pantheon in Paris, France.


References:

Allison, Andy; "Jean Perrin and Atomic Theory: Calculating Avagadro's Constant"; Physics @ Suite 101; October 3, 2008

Jean Perrin Nobel Biography

Jean Perrin Wikipedia Entry

Sunday, September 23, 2012

Alexandre Yersin

Alexander Yersin was born on September 22, 1863 in the village of Lavaux, on the shores of lake Geneva in Switzerland. He was the youngest of four children of a Swiss father and a French mother. His father, who as a high school teacher, died three weeks before he was born. He began his medical education in Lausanne, Switzerland, continued in Marburg, Germany and finished his PhD in medicine in Paris France, writing his thesis on tuberculosis in 1888.  In 1886 he became a French citizen. Also in 1886 he began working in the laboratories of Luis Pasteur at what would be the Pasteur Institute. With Pierre Roux he isolated the toxin from diphtheria and he participated in the development of rabies anti-serum.

Yersin quickly tired of working for Pasteur, who was notorious for taking credit for the work of those beneath him, so he signed on as a ship's doctor with Messangeries Maritimes, a shipping company. His duties were light and his first voyage took him to Saigon, Vietnam. Yersin spent many years in Vietnam, some on expeditions into unexplored parts and is a honored hero for the free medical consultations he gave. Streets bearing his name remained named after him following the communist revolution.

In 1894 he was sent by the Pasteur Institute and the French government to Hong Kong to investigate an outbreak of plague. When he arrived he found that Shibasaburo Kitasato, who had recently discovered the role of Clostridium tetani in lockjaw, was already working on isolating the bacterial cause of the plague. Yersin saw that Kitasato was culturing bacteria from the blood and organs of patients, but not the characteristic bubos of bubonic plague. Yersin was able to bribe two British sailors and gain access to the morgue. Using a sterile pipette he punctured the infected lymph node of a recently dead patient. He found faintly gram negative staining bacilli (rod-shaped bacteria) in the material he withdrew from the lymph node. He injected mice with the lymph node material and they quickly died. Autopsies showed the same slightly gram negatively staining bacilli.

Kitasato was quick to publish his results and claim credit for the discovery of the bacteria responsible for plague. Kitasato's cultures turned out not to be pure for the causative organism and Yersin was allowed to name the new bacteria. Pasturella pestis was his choice, honoring Pasteur, but since 1944 it has been Yersinia pestis. Yersina and Kitasato are considered co-discoverers of the organism.

In addition to his medical work, Yersin also tried his hand at agriculture, importing the Brazilian rubber tree and the quinine tree from the Andes to Vietnam. He was the director of the medical school at Ha Noi, Vietnam in its first two years (1902-1904).

He died on March 1, 1943.


References:

Burns, William; "Alexandre Yersin and His Adventures in Vietnam"; Mill Hill Essays 2003; National Institute for Medical Research; 2003

Maki, Rebecca; "The Discovery of Yersinia pestis"; at antimicrobe.org

Alexandre Yersin Wikipedia Entry


Monday, September 17, 2012

Albrecht Kossel

Ludwig Karl Martin Leonhard Albrecht Kossel was born on September 16, 1853 in Rostock, Mecklenburg. His father was a merchant, bank director and Prussian Council. Kossel attended gymnasium in Rostock and then in 1872 he went to the newly founded University of Strasbourg. As a youth he had shown an interest in chemistry and botany and he continued those studies at the university. He finished his studies at the University of Rostock, passing the state medical examination in 1877 and earning his medical doctor degree in 1878. After graduation he worked in the laboratory of Felix Hoppe-Seyler, who had been one of his biochemistry professors at Strasbourg.

Hoppe-Seyler in addition to being a biochemist was an inorganic chemist and was interested in what chemical elements made up living tissues. In his lab Kossel studied "nucleins" the newly isolated contents of cell's nuclei. Nucleins had been discovered by Friedrich Miescher in 1869. He had determined that they were chemically different from protein, being more acidic. In 1883 Kossel became the director of the Chemistry Division of the Physiological Institute at the University of Berlin. In the period from 1885 and 1901 Kossel isolated from nuclein the five nucleic acid bases that make up DNA and RNA: adenine, guanine, cytosine, thymine and Uracil. These five bases are the letters of the genetic code that code for proteins. In DNA, the instructions for construction proteins are written in four nucleotides: adenine, guanine, cytosine and thymine. In messenger RNAs, the translations of the DNA code that are sent to ribosomes, where proteins are made, thymine is replaced with uracil.

In 1895 Kossel became a professor of physiology and director of the Physiological Institute at the University of Marburg. In Marburg Kossel began to investigate the structure of proteins. In 1896 Kossel isolated histidine, an amino acid with a imidazol functional group. Kossel also was the first to isolate theophyllin a therapeutic drug found in cocoa and tea. In 1901 Kossel became the director of the Physiological Institute at Heidelberg University. In  1910 Kossel was awarded the Nobel Prize "in recognition of the contributions to our knowledge of cell chemistry made through his work on proteins, including the nucleic substances". In 1924 Kossel became professor emeritus at Heidelberg, but continued teaching. His research also continued as he continued working on determining the structure of proteins.

Kossel died on July 5, 1927.


References:

Jones, Mary Ellen; "A Biographical Sketch of Albrecht Kossel"; Yale Journal of Biology and Medicine(1953)26:80-97

Albrecht Kossel Nobel Biography

Albracht Kossel Wikipedia Entry

Sunday, September 9, 2012

Elliot Coues

Elliot Coues was born on Septermber 9, 1842 in Portsmouth, New Hampshire. His father Samuel Elliot Coues was a merchant and worked in the United States Patent Office, which caused him to be away from his family in New Hampshire starting when Coues was eleven. As a child Coues was fascinated by animals and was only interested in books that contained them.. When he moved to be with his father in Washington D.C, Coues went to the Smithsonian and there he met the naturalist Spencer Baird, the first curator of the Smithsonian, who would be his mentor. He published his first technical paper at the age of 19. He attended Gonzaga College High School in Washington D.C. and then Columbia College (which later would be renamed George Washington University) also in Washington D.C. Coues remained at Columbia College for ten years, earning a PhD and an MD.  Coues enlisted in the U.S. Army in 1862 as a medical cadet. In 1863 he was promoted to acting assistant surgeon and in 1864 to assistant surgeon. .

Coues' military career took him all over the United States, with postings in Arizona, North Carolina, California and North Dakota. Coues was an prolific writer and wrote many works on ornithology and natural history. In the Army he got the chance to join expeditions that explored parts of America, serving as both naturalist and surgeon on the United States Northern Boundary Commission form 1873-1876 and from 1876 to 1880 he served as secretary and naturalist to the United States Geological and Geographical Survey of the Territories. While in the army he authored 300 works and papers. He resigned from the army in 1881 to devote himself more fully to literary and scientific pursuits. After resigning from the Army he returned to Washington D.C. In 1877 he was appointed professor of Anatomy at the National Medical College and that same year he was elected to the National Academy of Sciences. He was one of the founders of the American Ornithologists Union and served as its president.

Coues' book A Key to North American Birds first edition was published in 1972. The book was at the time  a unique work of ornithology, one which for years other guides to animal species would follow. Other important works by Coues included A Checklist of North American Birds (two editions) and Field Ornithology. Coues identified for the first time many unknown bird species and introduced the trinomial nomenclature used to distinguish subspecies of animals. All living species are known by their scientific name composed of Latin genus and species names. Coues introduced using a third Latin name for subspecies. Coues was also important in mammology, publishing North American Fur Bearing Animals in 1877.

Coues died on December 25, 1899 at Johns Hopkins University Hospital in Baltimore, Maryland, during an operation to cure an afflicted throat.


References:

Allen, A.J.; "Biographical Memoir of Elliot Coues: 1842-1889"; in Biographical Memoirs Vol 6; National Academy Press; 1909

Anonymous; "A Great Ornithologist"; The Outlook(1900)64:89-90

Elliot, D.G.; "In Memoriam: Elliot Coues"; The Auk(1901)18:1-11

Elliot Coues Wikipedia Entry


Sunday, September 2, 2012

Wilhelm Ostwald

Friedrich Wilhelm Ostwald was born on September 2, 1853 in Riga, Latvia.  His father, Gottfried, was a master cooper and he was the middle of three brothers. His family was German in origin, but he attended a local kronsschule with Latvian and Russian children and he attended the local real gymnasium school. He matriculated to the University of Tartu in 1872 and after briefly enjoying fraternity life the influence of his father convinced him to take his academics seriously. He started working in the laboratory of Karl Schmidt. From Schmidt's assistant Johan Lemburg he learned the essentials of inorganic analysis and he earned his bachelor's degree in 1875 and his doctorate in 1978 working in Schmidt's lab.

In 1887 he served as an unpaid lecturer at the University of Tartu. Four years later he became a professor of chemistry at Riga Polytechnic University and six years after that be became professor of physical chemistry at Lepzig University. Ostwald remained at Lepzig until his retirement in 1906, except for one year as the first exchange professor at Harvard University in 1904-5. Ostward's lab became a center for instruction in physical chemistry and among his students were many Nobel Prize winners including Arrhenius, Van 't Hoff and Nernst. Albert Einstein applied to work in Ostwald's lab.

Ostwald began his research in 1875 studying the law of mass action of water with the problem of chemical affinity and with special emphasis on electrochemistry. This led to the discovery of the law of dilution, which is named after him and governs the disassociation of a weak acid or base. Ostwald became one of the founders of modern physical chemistry and wrote several textbooks on the subject. Ostwald founded Zeitschrift fur physikalsche Chemie in 1887 and remained its editor until 1922 editing over 100 volumes. He is the inventor of the Ostwald process for producing nitric acid, which he patented in 1902. His development of the mole concept (a mole of a chemical being equal to its atomic mass in grams) was ironically part of his resistance to atomic theory, against which he was one of the last holdouts.

Ostwald won the 1909 Nobel Prize "in recognition for his investigations into the fundamental principals governing chemical equilibria and rates of reaction". Besides chemistry Ostwald had many insterests including philosophy and painting, for which he produced his own pigments. Later in his career he wrote several books dealing with color theory.

Ostwald died on April 4, 1932.


References:

Kim, Mi Gyung; "Wilhelm Ostwald (1853-1932)"; 2006; at hyle.org

May, Leopold; "Wilhelm Ostwald"; 2003; at faculty.cua.edu

Wilhelm Ostwald Nobel Biography

Wilhelm Ostwald Wikipedia Entry

Sunday, August 26, 2012

James Franck

James Franck was born on August 26, 1882 in Hamburg, Germany. His father was a banker and his mother came from a family of rabbis. Franck attended Wilhelm Gymnasium in Hamburg and was not a brilliant scholar, only barely passing his high school final examinations. After high school he went to the University of Heidelberg, where he was to study law and economics, so that he could take a place at his father's firm. Franck was interested in science and took classes on chemistry and geology. At Heidelberg he met Max Born and the two became lifelong friends. With the help of Born he was able to persuade his father to let him study science and in 1902 he moved to Berlin where he studied physics under Emil Warburg and Paul Drude at the University of Berlin. He finished his PhD under Warburg in 1906, completing a thesis on the movement of ions in gaseous discharges.

After briefly working in Frankfurt-am-Main Frank returned to Berlin to work as an assistant for Heinrich Ruben, where he studied the structure of the electron shells of atoms and molecules, using atomic collisions. In 1911 Franck became a lecturer at the University of Berlin and when World War I broke out he enlisted and served as a private. In the war he was wounded, awarded the Iron Cross, first class, and then was promoted to lieutenant, despite his Jewish heritage. After his promotion he was assigned to a chemical warfare unit led by Fritz Haber, where he became Haber's assistant. After the war, at Haber's suggestion, Franck took a job at the Kaiser Wilhelm Institute of Physical Chemistry and in 1918 he became the head of the physics department.

Franck worked with Gustav Hertz and they studied the nature of electron collisions with atoms. From this work they were able to demonstrate the quantized nature of energy from electron transitions in atoms. In 1900 Max Planck had hypothesized that the energy emitted by excited atoms (atoms with electrons above their ground or lowest energy states) come in discrete amounts. When excited electrons fall back to their ground states they emit energy in the form of electromagnetic radiation. Because there are distinct electronic orbitals around the nucleus when electrons transition between these their emissions only come at certain wavelengths that depend on which orbitals the electrons transition between. Franck and Hertz's experiments were the first experimental demonstration of the quantized nature of electronic transitions. For these experiments Franck and Hertz were awarded the 1925 Nobel Prize in Physics.

In 1920 Franck moved to Gottingen where he was a professor of experimental physics at the Physical Institute. Franck's laboratory in Gottingen became a center for study of atomic and molecular physics and many important physicists studied there. In 1933, when the Nazis came to power in Germany, Franck moved to Baltimore, Maryland, where he was the Speyer Professor of Physics at Johns Hopkins University. He then spent a year in Copenhagen, Denmark, where he was a guest professor. In 1935 he returned to Johns Hopkins as a physics professor. He stayed at Johns Hopkins until 1938, when he moved to the University of Chicago, becoming a professor of physical chemistry. During World War II Franck was the director of the Chemistry Division of the Metallurgical Laboratory, which was part of the Manhattan Project. In 1945 he served as the chairman of the committee that produced the Franck Report, a document signed by several prominent physicists urging the United States Government not to use the atomic bomb on Japan and predicting the arms race. He became a professor emeritus at the University of Chicago in 1947, but continued doing research with the Photosynthesis Research Group until 1956.

Other honors won by Franck include the Planck Medal from the German Physical Society in 1951, the Rumford Medal in 1955 from the American Academy of Arts and Sciences for his work on photosynthesis and election as a foreign member of the Royal Society of London in 1964.

Franck died suddenly while on a brief trip to Gottingen on May 21,1963, at the age of 81.


References:

Rice, Stuart A. and Jortner, Joshua; "James Franck 1882-1964"; National Academy Press; 2010

James Franck Nobel Biography

James Franck Wikipedia Entry


Sunday, August 19, 2012

John Flamsteed

John Flamsteed was born on August 19, 1646 in Denby, in Darbyshire, England. His father Steven Flamsteed was the wealthy owner of a mating business. His mother, Mary, died soon after he was born. Flamsteed was educated at the Darby Free School but due to his rheumatic disease Flamsteed's father decided not to send him to a university. Instead Flamsteed, who was fluent in Latin, studied on his own learning astronomy from books. Another reason his father did not send him to the university was so that Flamsteed could keep his house and labor in his malt business. Because of this Flamsteed bore a lifelong resentment toward his father.  In 1661 He observed his first partial solar eclipse. Eventually Flamsteed was able to enroll at Jesus College, Cambridge, but he was only in residence for two months in 1674 and he received his MA by royal warrant also in 1674. He began corresponding with Henry Oldenburg and John Collins. These two arranged for Flamsteed to meet Jonas Moore, whom he met on a visit to the Royal Society in London in 1670.

In 1675 Flamsteed visited London and with the help of Moore was able to get an audience with king Charles II. Flamsteed had won the favor of the king by building a barometer for him the previous year. Charles II appointed Flamsteed his Royal Astronomer. Greenwich Observatory was built for his observations and he began observing there in 1676. Flamsteed was a careful observer and his project was to observe and catalog the locations of the stars. Over the forty years of his project he cataloged the positions of 3000 stars. Flamsteed was a meticulous worker and did not want to publish any results until they all were checked. Isaac Newton became impatient for the results of the catalog and obtained a pirated copy of the work, which he and Edmund Hally published. Flamsteed was so angry at this that he obtained 300 of the 400 copies that were printed and burned them. Because of this Flamsteed came to view Newton and Halley as his enemies. The finished catalog was not published until 1725.

Other accomplishments credited to Flamesteed include accurate predictions of the solar eclipses of 1666 and 1668 and the invention of the conical projection which is used in cartography. Even before his visit to London and appointment to become the first astronomer royal, Flamsteed had been ordained and he served as a parish priest in Burstow, Surrey. Honors won by Flamsteed include election to the Royal Society in 1677 and a crater on the moon and an asteroid named after him.

Flamsteed died on December 31, 1719 and he was replaced as astronomer royal by his enemy Edmund Hally.


References:

O'Conner, J.J. and Robertson, E.F.; "John Flamsteed"; found at www-history.mcs.st-and.ac.uk

Moulton, Charles Wells; Library of Literary Criticism of English and American Authors, Vol. 2, 1639-1729; Henry Malkan, Publisher; 1910

John Flamsteed Wikipedia Entry




Sunday, July 29, 2012

William Beebe

Charles William Beebe was born on July 29, 1877 in Brooklyn, New York. His father, Charles Beebe, was a paper dealer and was frequently away from home. When Beebe was 2 the family moved to East Orange, New Jersey, away from New York City, which his mother, Henrietta Younglove Beebe, found stifling. The family often took the train into New York City to visit the American Museum of Natural History where they attended lectures. Young Beebe often explored the wilderness around his family home and was an avid collector of animals and insects that he found there. Beebe attended East Orange High School and in 1896 he entered Columbia University in New York City. At Columbia he studied under Henry Osborn. Beebe did not complete his degree at Columbia, finishing all the classes neccessary for a degree except mathematics, and instead he took a job as the assistant curator of ornithology at the new New York Zoological Park, what is now the Bronx Zoo.

As assistant curator Beebe's job was to breed and rear the birds in the zoo's collection. Beebe wanted to give his avian charges the most space possible and so he proposed a "flying cage" the size of a football field, which was built, but only at half the size of his proposal. In 1901 he was part of expedition to Nova Scotia to collect marine animals for the zoo and the following year he was promoted to be a full curator. In 1903 Beebe took an expedition to the Florida keys. Suffering from a throat infection and it was thought that the expedition to the tropics would be beneficial. The expedition fueled Beebe's interest in the wildlife found in the tropics and was the first of many that he would make during his life.

Over the next several years Beebe made many expeditions to collect birds traveling to Mexico, British Guiana, Trinidad, Venezuela, and in 1909 he traveled to the far east on a 17 month expedition, visiting 21 countries and gathering material for a monograph on pheasants. Although the manuscript was completed by 1914, Beebe was fastidious in his desire to have excellent illustrations of the birds. Because of this and the outbreak of World War I the first volume (of four) was not published for 4 more years. In 1915 Beebe traveled to Brazil to obtain more birds for the zoo. The expedition was an important turning point for Beebe as his focus began to change from simply ornithology to studying jungle ecosystems.

After briefly serving as an aviation instructor for the American war effort, in 1918 Beebe began a series of expeditions including the Galapagos islands, the Sargasso Sea, and Haiti. Over the years Beebe's focus widened from just ornithology to study other areas of biology and oceanography. One of Beebe's most important contributions to the study of birds was the theory that the ancestors of modern birds had passed through a stage he referred to as the "tetraptrex" stage where the ancestral birds had four wings on both their fore and hind limbs. This theory was later verified by fossil evidence.

Beebe is probably most famous for his part in the development of the bathysphere. At the time deep sea diving was only possible in heavy and not very movable diving suits. Working with engineer Otis Barton, Beebe developed the bathysphere, an unpowered, spherical shell that was lowered from a ship by means of a cable and ocean life could be viewed through the quartz windows embedded in the side of the sphere. Using the bathysphere they had developed, Beebe and Otis set a world record on a half mile dive in 1934 of off Nonsuch Island in Bermuda. Beebe retired in 1952 at the age of 75.

Beebe died on June 4, 1962 in Simla, India and was buried in Trinidad.


References:

Crandall, Lee S.; "In Memoriam: William Charles Beebe"; The Auk (1964)81:36-42

Gould, Carol Grant; The Remarkable Life of William Beebe: Explorer and Naturalist; Island Press; 2004

Hines, Catherine L.; "William Charles Beebe"; 2000

William Beebe Wikipedia Entry

Monday, April 9, 2012

Melvin Calvin


Melvin Calvin was born on April 8, 1911 in St. Paul, Minnesota. His parents were Jewish immigrants, his father from Tsarist Lithuania and his mother from Tsarist Georgia. They ran a grocery store in Detroit, Michigan at which Calvin helped out when on break from school. His interest in chemistry was sparked by thinking about how the products that were sold in his parent's store worked. He attended Central High School in Detroit and then studied chemistry at the Michigan College of Mining and Technology where he earned the school's first chemistry bachelors in 1931. He earned his Ph. D. in chemistry in 1935 from the University of Minnesota, completing a thesis on the electron affinity of halogens. Halogens (including fluorine, chlorine, bromine and iodine) are period 17 on the periodic table of elements and have high electron affinities because they have seven electrons in their outer orbitals.

After finishing his Ph.D. he did a  postdoc at the University of Manchester in the lab of Michael Polanyi where he studied phthalocyanines, cyclic organic compounds that form complexes with other atoms and are used as dyes. After two years in Manchester he was offered a lecturer position at the University of California at Berkeley, in 1937, where he was the first non-Berkeley graduate to join the chemistry department in more than a quarter century. Working with Gilbert Lewis he studied the chemistry of the porphyrin the organic nitrogen ring compound found in the heme portion of the hemoglobin molecule. Poryphyrin rings complex with metallic atoms, iron in the case of hemoglobin. Calvin remained at U.C. Berkeley for the rest of his career, where he served as the founding director of the Laboratory of Chemical Biodynamics and as an associate director of the Berkeley Radiation Laboratory.

He was promoted to professor of chemistry in 1947. Calvin is most famous for using radioactive carbon to study the chemical reaction of the carbon fixation, the dark reaction of photosynthesis. In plants the enzyme ribulose-1,5-biphosphate oxygense (RuBisCO) adds carbon dioxide to the five carbon sugar ribulose-1,5-biphosphate, which breaks down into two three carbon phosphogycerate molecules. Carbon fixation is what distinguishes autotrophic plants the other heterotrophic kingdoms of organisms. The cyclic pathway by which carbon dioxide is incorporated by plants is called the Calvin cycle.

For his research on carbon assimilation by plants he was awarded the Nobel Prize in chemistry in 1961. His other honors include election to the National Academy of Science and a postage stamp honoring him in 2008. He served as president of both the American Chemical Society and the American Society of Plant Physiology. He also served as the president of the Pacific Division of the American Society for the Advancement of Science. He served as an adviser to the National Aeronautics and Space Administration regarding the transmission and encounter of pathogens and organic compounds on the Moon and the planets of our solar system. He also served as a presidential scientific adviser. He retired from Berkeley in 1980 but remained doing research until 1996.

He died of a heart attack on January 8, 1997.


References:

Seaborg, Glenn T. and Benson, Andrew A.; "Melvin Calvin: April 8, 1911-January 8, 1997"; Biographical Memoirs Vol 75; National Academy Press; 1998

Melvin Calvin Nobel Biography

Melvin Calvin Wikipedia Entry

Sunday, March 18, 2012

Sir Norman Haworth

Walter Norman Haworth was born on March 19, 1883 in Chorley, Lancashire, England the second son and fourth child of Thomas and Hannah Haworth. His father was the manager of a linoleum plant. After attending the local school until the age 14 Haworth joined his father and learned about linoleum design and manufacture. His interest in chemistry began when he studied the dyes used to color linoleum. He continued his education studying under a tutor in the neighboring town of Preston, which allowed him to pass the entrance examination for the University of Manchester. Against his family's wishes he began at the University of Manchester, studying chemistry under W.H. Perkin. He graduated with first class honors in 1906. On the basis of his work under Perkin he was awarded a 1851 Exhibition Scholarship which allowed him to study in the laboratory of Otto Wallach in Gottingen, Germany earning his doctorate in one year of study. He returned to Manchester where in the minimum time possible he was awarded his D. Sc. for his work on terpenes. Terpenes are produced by plants and their building block are units of isoprene.

In 1911 Haworth took an appointment as a demonstrator at the Imperial College of Science and Technology in London and in 1912 he was appointed a lecturer at the University of St. Andrews in Scotland. At St. Andrews he became interested in the chemistry of carbohydrates while working with Thomas Purdie and James Irvine. Haworth organized the laboratories at St. Andrews for the production of chemicals and drugs during the First World War. In 1920 he was called to take the chair of chemistry at the University of Durham. The following year he succeeded Philips Bedson as director. In 1925 Haworth was appointed professor and director of chemistry at the University of Birmingham where he remained until 1948. Then he became the dean of science and he served as an acting vice-principal from 1947 to 1948.

Haworth's research centered around carbohydrates and he determined the structures of many, including maltose, cellobiose, lactose, gentiobiose, melibiose, gentianose, and raffinose. He was also responsible for discovering the glucoside ring structure of normal sugars. Normal sugars that are five or six carbons long form a ring structure where the terminal hydroxyl nucleophillically attacks the aldehyde carbon forming an glycosidic bond. He developed Haworth projections which are two dimensional representations of three dimensional sugar structures. Haworth was also the first person to chemically synthesize vitamin C, the first vitamin artificially synthesized.

For his work understanding the structures of carbohydrates and the synthesis of vitamin C Haworth shared the 1935 Nobel Prize in Chemistry with Paul Karrer. In 1947 Haworth was knighted. In 1977 the Royal Mail issued a postage stamp honoring Haworth for his Nobel Prize and the synthesis of Vitamin C.

He died suddenly on his 67th birthday, March 19, 1950.


References:

Anon, "Walter Norman Haworth: 1883-1950" in Advances in Carbohydrates(1951)6:1

Norman Haworth Nobel Biography

Norman Haworth Wikipedia Entry

Sunday, March 11, 2012

Urbain Jean Joseph LeVerrier


Urbain Jean Joseph LeVerrier was born in St. Lo in Normandy, France on March 11, 1811. As a boy he showed an aptitude for mathematics when he attended school in Caen, but he was turned down from the prestigious Ecole Polytechnique in Paris. In order to help his son, his father sold the family home so that LeVerrier could attend the College de St. Louis in Paris. A year later, when LeVaerrier reapplied to the Ecole Polytechnique his application was accepted, winning the mathematics prize. LeVerrier graduated in the top of his year and briefly took a job working for the chemist Joseph Gay-Lussac.

In 1837 he returned to the Ecole Polytechnique as an astronomy assistant. His first major piece of work was looking in to the stability of the solar system. In 1840 Dominique Arago, the director of the Paris Observatory, suggested he look into the motion of Mercury, which he did. LeVerrier predicted the start of the transit of Mercury of May 1845 to within 16 seconds. Next Arago had LeVerrier look in to the motion of Uranus, which was not moving as predicted. LeVerrier calculated that the perturbations of Uranus' orbit were due to the presence of another planet, further from the sun than Uranus. Unknown to Arago and LeVerrier, in England, John Crouch Adams had previously reached the same conclusion. Adams had sent his work to George Airy, the royal astronomer and James Challis, the director of the Cambridge Observatory. Neither man acted on Adams' findings until after LeVerrier had published his work in June of 1846. After LeVerrier published, Airy attempted to observe the planet, but it was not seen until September of 1846 when what would be named Neptune was observed by Johan Galle and Heinrich d'Arrest in Berlin.

In 1849 he was elected to the French Legislative Assembly. In 1852 he was appointed a senator and member of the Superior Council of Public Instruction on which he served until 1870. When Arago died in 1854, LeVerrier became director of the Paris Observatory. He was removed as director in 1870 but was reinstated in 1873. He was awarded a gold medal by the Royal Society of London in 1868 and 1876. He has craters named after him on the Moon and on Mars and he is one of the 72 names inscribed on the Eiffel Tower.

He died in Paris on September 23, 1877.


References:

Anon.;"Urbain-Jean-Joseph LeVerrier" in Proceedings of the American Academy of Arts and Sciences(1978)13:454-455

Dunkin, E. "M LeVerrier" in The Observatory (1877)1:199-206

Leverington, David; Babylon to Voyager: A history of Planetary Astronomy; Cambridge University Press; 2003

Urbain LeVerrier Wikipedia Entry


Sunday, March 4, 2012

George Gamow

Georgiy Antonovich Gamov was born on March 4, 1904 by cesarean section on a table in his father's library in Odessa then part of the Russian Empire (now in Ukraine). Both of his parents were teachers; his father taught Russian language and literature at a boys school and his mother taught geography and history at a girls school. His maternal grandfather was the archbishop of Odessa and his paternal grandfather was a commander in the Russian Army. At age six he saw Halley's comet from the rooftop of his family's building and from astronomy he became interested in physics. The Russian Revolution struck while he was a student at the school where his father taught which was frequently closed due to street fighting. He graduated in 1920 and went on to Odessa State University, but was unable to study physics there due to the privations caused by the revolution. In 1923 he went to the University of Leningrad (now St. Petersburg State University). There he studied under Alexander Friedman, however Friedman died in 1925.

While studying conventional physics at the university Gamow met with other students to read the papers coming from western Europe that were defining the new science of quantum mechanics. Gamow was interested in the new theories and sometimes neglected his studies in classical physics. In 1928, after being admonished for unsatisfactory academic progress, he was given a fellowship which allowed him to go to Germany. Gamow traveled to Gottingen, where he studied under Max Born at the Institute for Theoretical Physics. While there he authored a paper explaining why radioactive nuclei emit low energy alpha particles, but when bombarded by alpha particles of higher energy they are not incorporated by the nuclei. Alpha particles are a product of radioactive decay composed of two protons and two neutrons, a helium nuclei. After four months in Gottingen Gamow's money ran out and he headed home. On the way back to Russia he stopped in Copenhagen, Denmark where he ended up staying for eight months. While there he had the chance to present a paper to the Royal Society of London, quite an honor for a 25 year old scientist.

After Gamow returned to the Soviet Union he decided to leave due to the increased political repression. In 1932, after three aborted attempts to defect, which were not noticed by the authorities, he was granted passports so that he and his wife, Rho, could go to a conference in Brussels. After the conference Gamow tried to find work in Europe. He did get a few temporary positions but it was not until 1934 that he could find a permanent position at George Washington University in Washington D.C. In 1940 Gamow was naturalized as a U.S. Citizen. He remained at George Washington University until 1956. Despite his knowledge of atomic physics during the Second World War he did not work on the Manhattan Project, but stayed at Washington University and did some consulting for the United States Navy. In 1954 he became a visiting professor at the University of California at Berkeley and in 1956 he took a position at the University of Colorado at Boulder, where he remained for the rest of his career.

Gamow studied beta emission, the emission of an electron by a radionuclei and nucleosynthesis, the creation nuclei larger than a single proton (hydrogen) inside stars. Stars are powered by atomic reactions such as hydrogen forming helium and releasing energy. Helium, with its two protons and two neutrons, then is used to form even numbered atomic elements (beryllium, carbon, and oxygen). Gamow worked to popularize the big bang theory, the theory that the universe and all the matter in it was created in a big bang. Gamow's most important work in astrophysics was on understanding the generation of red giants, stars that have exhausted the supply of hydrogen at their core. When the reaction producing helium stops the core collapses due to gravity. The conversion of hydrogen into helium continues in the region surrounding the stellar core, which expands creating a red giant star. After the 1953 discovery of the structure of DNA Gamow attempted, unsuccessfully, to solve the problem of how the genetic code translates into proteins. Gamow was also an award winning writer of both scientific and popular books. The physics tower at the University of Colorado, in Boulder is named after him.

Gamow died on August 19, 1968.


References:

Interview with George Gamow by Charles Weiner on April 25, 1968. Neils Bohr Library and Archives, American Institute of Physics; online at aip.org

Hufbauer, Karl; "George Gamow: 1904-1968" in Biographical Memoirs; National Academy Press; 2009

George Gamow Wikipedia Entry

Sunday, February 26, 2012

Joseph LeConte

Joseph LeConte was born on February 26, 1823 on the plantation "Woodmanston" in Liberty County, Georgia. He was the fifth child and youngest son in the family. His mother died of pneumonia when he was three. His father, who had trained as a doctor, but did not earn a degree, ran the family plantation and set up a chemical laboratory in his house and a botany garden for the education of his sons. As a boy LeConte frequently ranged the backwoods of Liberty County with his older brothers and took an interest in nature. He attended a country school set up by several of the plantation families and among his teachers was Alexander Hamilton Stephens, who was later a U.S. Senator and vice-president of the Confederacy, and with whom he maintained a lifelong friendship.

He attended Franklin College which later founded the University of Georgia in Athens, Georgia. He graduated in 1841. After graduation he began studying medicine under Charles West in Macon, Georgia and then he attended the New York College of Physicians and Surgeons, graduating with a medical degree in 1845. He practiced medicine for three years in Macon, Georgia and then studied history at Harvard University, in Boston, Massachusetts, studying under Louis Agassiz. After graduation in 1851, he accompanied an expedition lead by Agassiz to the Florida Reef. After the expedition he became a professor of natural science at Oglethorpe College in Midway, Georgia. From 1852 to 1856 he was a professor of natural sciences and geology at Franklin College and from 1857 to 1869 he was a professor of chemistry and geology at South Carolina College (later the University of South Carolina) in Columbia, South Carolina. During the American Civil War he continued teaching, but also ran a niter works used to produce explosives. In 1869 he moved to California, taking a job as the first professor of natural history and geology at the newly founded University of California, at Berkeley. He remained there until his death.

LeConte was primarily a geologist but he also wrote papers on monocular and binocular vision. He was also an early proponent of Charles Darwin's theory of natural selection. LeConte was one of the early supporters of the theory of contraction formation of mountain ranges. The theory was that when the earth was formed it was a molten ball  and as it cooled ridges on the surface developed. These ridges are the mountain ranges we see today. This theory of mountain range formation has been replaced by plate tectonic theory. LeConte was also an ardent conservationist. He was friends with John Muir, and with Muir was a co-founder of the Sierra Club. In 1874 he was nominated to the National Academy of Science. He served as president of the American Association for the Advancement of Science in 1892 and president of the Geological Society of America in 1896.

He died on July 6, 1901 of a heart attack, while in Yosemite Valley. He was to be leaving on a Sierra Club trip the next day.


References:

LeConte, Joseph; "The Autobiography of Joseph LeConte", edited by William Dallam Ames; D. Appleton and Company; 1903

Hilgard, Eugene W.; "Biographical Memoir of Joseph LeConte: 1823-1901"; in Biographical Memoirs; National Academy Press; 1907

Joseph LeConte Wikipedia Entry

Sunday, February 19, 2012

Svante August Arrhenius

Svante August Arrhenius was born on February 19, 1859 in Vik, a village near Uppsala, Sweden. His father, Svante Gustaf Arrhenius, was a land surveyor who worked for the University of Uppsala. The family moved to Uppsala in 1860. A gifted child, Arrhenius learned to read from lessons given by his older brother Janne. He learned to do arithmetic by watching his father keeping the accounts that he was responsible for. At age 8 he entered the local cathedral school, starting in 5th grade. He excelled at mathematics and physics, graduating as the youngest and most able student in 1876. In the autumn of 1876 Arrhenius entered the University of Uppsala, where he studied mathematics, physics and chemistry. He finished his bachelors in January 1878, finishing in a year and a half, a record at the time.

After a trip to Paris, he began his graduate studies in physics at the University of Uppsala, but due to the poor instruction he moved to Stockholm, studying under Erik Edland at the Physical Institute of the Swedish Academy of Sciences. Arrhenius began working for Edland studying electrical spark discharges, but moved on to studying the dissolution of electrolytes in water. Electrolytes are chemicals that when added to water make a solution that conducts electricity. Arrhenius discovered that electrolytes, when dissolved in water, break up into negatively and positively charged particles called ions. His thesis was not well received by his professors and was given the lowest possible passing grade.  Only after his defense was it raised to a third class rating.

 Arrhenius sent his thesis to two of the leading physical chemists of the time, Jacobus van't Hoff and Wilhelm Ostwald. Ostwald was so impressed that after some correspondence he traveled to Uppsala to offer Arrhenius a docent position in Riga, which at that time was part of the Russian Empire. Arrhenius decided to stay in Sweden and he was given an unpaid docent position at the University of Uppsala, the first such position in the emerging science of physical chemistry. In 1885, with the recommendation of Edland he received a traveling fellowship from the Swedish Academy of Science that allowed him to travel through Europe and work with prominent physical chemists. In 1886 he traveled to Riga to work with Ostwald and to Wurzburg to work with Friedrich Kohlrausch. In 1887 he traveled to Graz to work with Ludwig Boltzmann and in 1888 he traveled to Amsterdam to work with van't Hoff. During these trips he studied the effects of ions in solution, including the increase in the boiling point and lower the freezing point of ionic solutions versus pure solvents and the effects of ions in digestion and in the interaction of toxins and anti-toxins.

It was not until 1891, after he refused the offer of a professorship in Giessen, Germany, that he was made lecturer at Stockholm University College and in 1895 he was appointed professor of physics. In 1886 after studying the causes of ice ages he published a paper linking atmospheric carbon dioxide levels and rising temperatures. He calculated that if the level of carbon dioxide in the atmosphere doubled the temperature would rise by 5o-6oC. Scientists today say that it is really only a 2o-3oC rise in temperature. This rise in temperature is caused by the infrared absorption of carbon dioxide. The sun's rays warm the earth and it cools by releasing infrared radiation. This radiation is absorbed by carbon dioxide in the atmosphere and reflected back to earth, preventing it from escaping back into space. This is called the greenhouse effect, where carbon dioxide in the atmosphere keeps the earth warm by preventing heat from escaping. The cumulative effect of carbon dioxide and other greenhouse gasses give rise to global warming.

Around 1900 Arrhenius became involved with the Nobel Prize. In 1897, with the death of Alfred Nobel, the Swedish scientific establishment was left with the task of organizing the bequest from his will, prizes awarded to outstanding achievements in chemistry, medicine, physics, economics, literature, and peace that benefit mankind. Arrhenius was largely responsible for setting up the rules that govern the prizes. In 1903 he won the Nobel Prize for Chemistry for his work on the "electrolyte theory of dissociation". This was partly work he had done on his doctoral dissertation that only earned third class honors. Other honors he won include election as a foreign member to the Royal Society of England in 1911, the Society's Davy Medal and the Faraday Medal given by the Chemical Society, as well as many honorary doctorates.

Arrenius spent his later years writing  scientific textbooks and science books for a lay audience and he died on October 2, 1927 in Stockholm. He was buried in Uppsala.


References:

Arrhenius, Gustav; Caldwell, Karen; and Wold, Svante; "A tribute to the memory of Svante Arrhenius (1859-1927)"; The Royal Swedish Academy of Engineers (2008)

Sample, Ian; "The Father of Climate Change"; The Guardian; June 30, 2005

Svante Arrhenius Wikipedia Entry

Svante Arrhenius Nobel Biography


Sunday, February 12, 2012

Marcel Gilles Jozef Minnaert

Marcel Gilles Jozef Minnaert was born on February 12, 1893 in Burges, Belgium. His father and mother were school teachers, liberal and supportive of Flemish causes. Minnaert, in his youth was influenced by his uncle, Gerard Minnaert, who was important in the Flemish movement. He grew up in a part of Belgium where Dutch was the common language but all the schools taught in French. After his father's death in 1902 his mother moved the family to Gent, Belgium. Minnaert went to secondary school in Gent and then to the University of Gent, where he studied natural sciences, particularly biology. While a student he was part of a movement to change the language of the university from French to Dutch. He earned his doctorate in biology in 1914.

In 1915-16 he spent a year in Leiden in order to study mathematics and physics. During the German occupation of Belgium he taught physics at the University of Gent, but was forced to flee in 1918, when the Germans left, because he was seen as a collaborator. He relocated to the University of Utrehct, in the Netherlands, where he worked for W.H. Julius who stimulated his interest in solar physics. He finished his second doctorate, this time in astronomy in 1925 the same year that Julius died. Minnaert replaced Julius as the director of the solar spectrograph research project at Utrecht. This was a fascinating time in stellar physics when atomic physics could finally explain what was really happening. Stars, like our sun, are fusing nucleons together, creating new atoms, making the matter that we are made of.

In 1928 he led a successful solar eclipse expedition. In 1940 he published the Utrecht Atlas of the Solar Spectrum and in 1941 he developed the Minnaert function, which is used in the observation of celestial bodies. In 1942, Minnaert, who never hid his liberal political views was taken prisoner by the Germans. He taught physics to his fellow prisoners while he was imprisoned. He was released in 1944. After the war, he returned to the University of Utrecht's observatory and remained director until his retirement in 1963. In addition to his astronomical writings Minnaert also published a physics book that was popular in the Netherlands and was translated, and also a book of poetry dealing with astronomical subjects. Honors won by Minneart include the Bruce medal, presented by the Astronomical Society of the Pacific in 1951 and a gold medal from the Royal Society of London, in 1947. Minneart also has a crater on the moon and an asteroid named after him.

Mineart died on October 26, 1970.


References:

De Jager, C.; "In Memoriam: Marcel Gilles Jozef Minnaert (12 Februarty 1893-26 October 1970)"; Astrophysics and Space Science(1971)10:83-85

Unsold, Albrecht;"In Memorian: Marcel Gilles Jozef Minnaert";Solar Physics(1971)17:3-5

Anon; "Biographies: Marcel Gilles Jozef Minnaert"; online at www.dwc.knaw.nl

Marcel Minnaert Wikipedia Entry