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1913 In Science
The year 1913 in science and technology involved some significant events, listed below. Astronomy * February 9 – Meteor procession of February 9, 1913 visible along a great circle arc 6,040 miles (9,720 km) across the Americas. Astronomer Clarence Chant concludes that the source was a small, short-lived natural satellite of the Earth. * Berlin Observatory moves to Babelsberg. Biology * William Temple Hornaday publishes Our Vanishing Wild Life: Its Extermination and Preservation'. Chemistry * February – Daniel J. O'Conor and Herbert A. Faber file for a United States patent on the composite plastic laminate Formica. * Elmer McCollum and Marguerite Davis at the University of Wisconsin–Madison, and Lafayette Mendel and Thomas Burr Osborne at Yale University independently discover Vitamin A. * Protactinium is first identified by Oswald Helmuth Göhring and Kasimir Fajans. * Henry Moseley shows that nuclear charge is the real basis for numbering the elements and discove ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science
Science is a systematic endeavor that builds and organizes knowledge in the form of testable explanations and predictions about the universe. Science may be as old as the human species, and some of the earliest archeological evidence for scientific reasoning is tens of thousands of years old. The earliest written records in the history of science come from Ancient Egypt and Mesopotamia in around 3000 to 1200 BCE. Their contributions to mathematics, astronomy, and medicine entered and shaped Greek natural philosophy of classical antiquity, whereby formal attempts were made to provide explanations of events in the physical world based on natural causes. After the fall of the Western Roman Empire, knowledge of Greek conceptions of the world deteriorated in Western Europe during the early centuries (400 to 1000 CE) of the Middle Ages, but was preserved in the Muslim world during the Islamic Golden Age and later by the efforts of Byzantine Greek scholars who brought Greek ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elmer McCollum
Elmer Verner McCollum (March 3, 1879 – November 15, 1967) was an American biochemist known for his work on the influence of diet on health.Kruse, 1961. McCollum is also remembered for starting the first rat colony in the United States to be used for nutrition research. His reputation has suffered from posthumous controversy. ''Time'' magazine called him Dr.Vitamin. His rule was, "Eat what you want after you have eaten what you should." Living at a time when vitamins were unknown, he asked and tried to answer the questions, "How many dietary essentials are there, and what are they?" He and Marguerite Davis discovered the first vitamin, namedA, in 1913. McCollum also helped to discover vitaminB and vitaminD and worked out the effect of trace elements in the diet. As a worker in Wisconsin and later at Johns Hopkins, McCollum acted partly at the request of the dairy industry. When he said that milk was "the greatest of all protective foods", milk consumption in the United States d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atomic Number
The atomic number or nuclear charge number (symbol ''Z'') of a chemical element is the charge number of an atomic nucleus. For ordinary nuclei, this is equal to the proton number (''n''p) or the number of protons found in the nucleus of every atom of that element. The atomic number can be used to uniquely identify ordinary chemical elements. In an ordinary uncharged atom, the atomic number is also equal to the number of electrons. For an ordinary atom, the sum of the atomic number ''Z'' and the neutron number ''N'' gives the atom's atomic mass number ''A''. Since protons and neutrons have approximately the same mass (and the mass of the electrons is negligible for many purposes) and the mass defect of the nucleon binding is always small compared to the nucleon mass, the atomic mass of any atom, when expressed in unified atomic mass units (making a quantity called the "relative isotopic mass"), is within 1% of the whole number ''A''. Atoms with the same atomic number but dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wavelength
In physics, the wavelength is the spatial period of a periodic wave—the distance over which the wave's shape repeats. It is the distance between consecutive corresponding points of the same phase on the wave, such as two adjacent crests, troughs, or zero crossings, and is a characteristic of both traveling waves and standing waves, as well as other spatial wave patterns. The inverse of the wavelength is called the spatial frequency. Wavelength is commonly designated by the Greek letter ''lambda'' (λ). The term ''wavelength'' is also sometimes applied to modulated waves, and to the sinusoidal envelopes of modulated waves or waves formed by interference of several sinusoids. Assuming a sinusoidal wave moving at a fixed wave speed, wavelength is inversely proportional to frequency of the wave: waves with higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths. Wavelength depends on the medium (for example, vacuum, air, or water) that a wav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Moseley
Henry Gwyn Jeffreys Moseley (; 23 November 1887 – 10 August 1915) was an English physicist, whose contribution to the science of physics was the justification from physical laws of the previous empirical and chemical concept of the atomic number. This stemmed from his development of Moseley's law in X-ray spectra. Moseley's law advanced atomic physics, nuclear physics and quantum physics by providing the first experimental evidence in favour of Niels Bohr's theory, aside from the hydrogen atom spectrum which the Bohr theory was designed to reproduce. That theory refined Ernest Rutherford's and Antonius van den Broek's model, which proposed that the atom contains in its nucleus a number of positive nuclear charges that is equal to its (atomic) number in the periodic table. This remains the accepted model today. When World War I broke out in Western Europe, Moseley left his research work at the University of Oxford behind to volunteer for the Royal Engineers of the British Ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kasimir Fajans
Kazimierz Fajans (Kasimir Fajans in many American publications; 27 May 1887 – 18 May 1975) was a Polish American physical chemist of Polish-Jewish origin, a pioneer in the science of radioactivity and the discoverer of chemical element protactinium. Education and career He was born May 27, 1887, in Warsaw, Congress Poland, to a family of Jewish background. After he had completed secondary school in Warsaw (1904), he started studying chemistry in Germany, at first at the University in Leipzig, and then in Heidelberg and Zürich. In 1909 he was awarded a PhD degree for his research into the stereoselective synthesis of chiral compounds. In 1910 Fajans took a job at the laboratory of Ernest Rutherford in Manchester, where the nucleus was discovered. He then returned to Germany, where he took the position of an assistant and later became the assistant professor at the Technical University of Karlsruhe. He researched into radioactivity. In 1917 he took over the Faculty of Physical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oswald Helmuth Göhring
Oswald Helmuth Göhring, also known as Otto Göhring, (1889 - 1915) was a German chemist who, with his teacher Kasimir Fajans, co-discovered the chemical element protactinium in 1913. Discovery of protactinium Protactinium was first identified in 1913 by Kasimir Fajans and Oswald Helmuth Göhring at the University of Karlsruhe. The new element was called brevium due to the short half-life of the isotope specific studied, Protactinium-234 (234 Pa). Fajans and Göhring also worked to identify as many isotopes of the new element as possible, and also to publicize their discovery—a process that was hampered by the onset of World War I. In 1914, Göhring was conscripted into the army. Presumably he perished during the war; he is listed as the author of no further scientific articles or publications after 1915. A stable isotope of this element was discovered in 1918, and thus the name was changed to protoactinium, and then in 1949 to its present name, protactinium. Publications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protactinium
Protactinium (formerly protoactinium) is a chemical element with the symbol Pa and atomic number 91. It is a dense, silvery-gray actinide metal which readily reacts with oxygen, water vapor and inorganic acids. It forms various chemical compounds in which protactinium is usually present in the oxidation state +5, but it can also assume +4 and even +3 or +2 states. Concentrations of protactinium in the Earth's crust are typically a few parts per trillion, but may reach up to a few parts per million in some uraninite ore deposits. Because of its scarcity, high radioactivity and high toxicity, there are currently no uses for protactinium outside scientific research, and for this purpose, protactinium is mostly extracted from spent nuclear fuel. The element was first identified in 1913 by Kazimierz Fajans and Oswald Helmuth Göhring and named ''brevium'' because of the short half-life of the specific isotope studied, i.e. protactinium-234. A more stable isotope of protactinium, 231Pa, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Biological Chemistry
The ''Journal of Biological Chemistry'' (''JBC'') is a weekly peer-reviewed scientific journal that was established in 1905., jbc.org Since 1925, it is published by the American Society for Biochemistry and Molecular Biology. It covers research in areas of biochemistry and molecular biology. The editor is Alex Toker. As of January 2021, the journal is fully open access. In press articles are available free on its website immediately after acceptance. Editors The following individuals have served as editors of the journal: * 1906–1909: John Jacob Abel and Christian Archibald Herter * 1909–1910: Christian Archibald Herter * 1910–1914: Alfred Newton Richards * 1914–1925: Donald D. Van Slyke * 1925–1936: Stanley R. Benedict. After Benedict died, John T. Edsall served as temporary editor until the next editor was appointed. * 1937–1958: Rudolph J. Anderson * 1958–1967: John T. Edsall * 1968–1971: William Howard Stein * 1971–2011: Herbert Tabor * 2011–2015: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitamin A
Vitamin A is a fat-soluble vitamin and an essential nutrient for humans. It is a group of organic compounds that includes retinol, retinal (also known as retinaldehyde), retinoic acid, and several provitamin A carotenoids (most notably beta-carotene ²-carotene. Vitamin A has multiple functions: it is essential for embryo development and growth, for maintenance of the immune system, and for vision, where it combines with the protein opsin to form rhodopsin the light-absorbing molecule necessary for both low-light (scotopic vision) and color vision. Vitamin A occurs as two principal forms in foods: A) retinol, found in animal-sourced foods, either as retinol or bound to a fatty acid to become a retinyl ester, and B) the carotenoids alpha-carotene, β-carotene, gamma-carotene, and the xanthophyll beta-cryptoxanthin (all of which contain β-ionone rings) that function as provitamin A in herbivore and omnivore animals which possess the enzymes that cleave and convert provi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yale University
Yale University is a private research university in New Haven, Connecticut. Established in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and among the most prestigious in the world. It is a member of the Ivy League. Chartered by the Connecticut Colony, the Collegiate School was established in 1701 by clergy to educate Congregational ministers before moving to New Haven in 1716. Originally restricted to theology and sacred languages, the curriculum began to incorporate humanities and sciences by the time of the American Revolution. In the 19th century, the college expanded into graduate and professional instruction, awarding the first PhD in the United States in 1861 and organizing as a university in 1887. Yale's faculty and student populations grew after 1890 with rapid expansion of the physical campus and scientific research. Yale is organized into fourteen constituent schools: the original undergraduate col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Burr Osborne (chemist)
Thomas Burr Osborne (August 5, 1859 – January 29, 1929) was a biochemist who, with Lafayette Mendel, independently discovered Vitamin A, though Elmer McCollum and Marguerite Davis were ultimately given credit, as they had submitted their paper first by three weeks. He is known for his work isolating and characterizing seed proteins, and for determining protein nutritional requirements. His career was spent at the Connecticut Agricultural Experiment Station. Biography Thomas Burr Osborne was born in New Haven, Connecticut on August 5, 1859. He was the son of lawyer Arthur Dimon Osborne and the grandson of US Representative Thomas Burr Osborne. He earned an undergraduate degree from Yale College in 1881, and a PhD in chemistry there in 1885. He married Elizabeth Annah Johnson on June 23, 1886, and they had one son. Osborne died at his home in New Haven on January 29, 1929. Career His life exhibited "a single purpose, the understanding of the relationships of proteins to eac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
