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Frank Hawthorne
Frank Christopher Hawthorne (born 8 January 1946 in Bristol, England) is a Canadian mineralogist, crystallographer and spectroscopist. He works at the University of Manitoba, Winnipeg, Manitoba, Canada, and is currently Distinguished Professor Emeritus. By combining Graph Theory, Bond-Valence TheoryThe Chemical Bond in Inorganic Chemistry. The Bond Valence Model, 2nd ed. Oxford University Press. and the moments approach to the electronic energy density of solidsBurdett JK, Lee S, Sha WC (1984) The method of moments and the energy levels of molecules and solids. Croat Chem Acta 57: 1193–1216, he has developed Bond TopologyHawthorne, F.C. (2012) A bond-topological approach to theoretical mineralogy: crystal structure, chemical composition and chemical reactions. Physics and Chemistry of Minerals, 39, 841–874.Hawthorne, F.C. (2015) Toward theoretical mineralogy: a bond-topological approach. American Mineralogist 100, 696-713. as a rigorous approach to understanding the atomic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bristol
Bristol () is a city, ceremonial county and unitary authority in England. Situated on the River Avon, it is bordered by the ceremonial counties of Gloucestershire to the north and Somerset to the south. Bristol is the most populous city in South West England. The wider Bristol Built-up Area is the eleventh most populous urban area in the United Kingdom. Iron Age hillforts and Roman villas were built near the confluence of the rivers Frome and Avon. Around the beginning of the 11th century, the settlement was known as (Old English: 'the place at the bridge'). Bristol received a royal charter in 1155 and was historically divided between Gloucestershire and Somerset until 1373 when it became a county corporate. From the 13th to the 18th century, Bristol was among the top three English cities, after London, in tax receipts. A major port, Bristol was a starting place for early voyages of exploration to the New World. On a ship out of Bristol in 1497, John Cabot, a Venetia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maidenhead
Maidenhead is a market town in the Royal Borough of Windsor and Maidenhead in the county of Berkshire, England, on the southwestern bank of the River Thames. It had an estimated population of 70,374 and forms part of the border with southern Buckinghamshire. The town is situated west of Charing Cross, London and east-northeast of the county town of Reading, Berkshire, Reading. The town differs from the Maidenhead (UK Parliament constituency), Parliamentary constituency of Maidenhead, which includes a number of outer suburbs and villages (including parts of Wokingham and Reading) such as Twyford, Berkshire, Twyford, Charvil, Remenham, Ruscombe and Wargrave. History The antiquary John Leland (antiquary), John Leland claimed that the area around Maidenhead's present town centre was a small Roman settlement called Alaunodunum. He stated that it had all but disappeared by the end of the Roman occupation. Although his source is unknown, there is documented and physical evidence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petr Černý
Petr Černý FRSC (8 January 1934 – 7 April 2018) was a mineralogy professor at the University of Manitoba. Černý's studies focus on pegmatite. He is best known for his geological mapping of Bernic Lake, Manitoba in the 1970s. The site has since hosted several tantalum-lithium-caesium mines, for example the Tanco Mine. Honours *1991, made a fellow of the Royal Society of Canada *1991, bestowed an honorary doctorate by the University of Manitoba *1993, awarded the Logan Medal by the Geological Association of Canada The Geological Association of Canada (GAC) is a learned society that promotes and develops the Geology, geological sciences in Canada. The organization holds conferences, meetings and exhibitions for the discussion of geological problems and the ... *the mineral cernyite was named in his honour *elected an honorary member of the Learned Society of Czech Republic *received a medal from the Asociacion Geologica Argentina References University of Manitoba Alumni N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DuPont (1802–2017)
DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in the development of Delaware and first arose as a major supplier of gunpowder. DuPont developed many polymers such as Vespel, neoprene, nylon, Corian, Teflon, Mylar, Kapton, Kevlar, Zemdrain, M5 fiber, Nomex, Tyvek, Sorona, Corfam and Lycra in the 20th century, and its scientists developed many chemicals, most notably Freon (chlorofluorocarbons), for the refrigerant industry. It also developed synthetic pigments and paints including ChromaFlair. In 2015, DuPont and the Dow Chemical Company agreed to a reorganization plan in which the two companies would merge and split into three. As a merged entity, DuPont simultaneously acquired Dow and renamed itself to DowDuPont on August 31, 2017, and after 18 months spin off the merged entity's ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mössbauer Spectroscopy
Mössbauer spectroscopy is a spectroscopic technique based on the Mössbauer effect. This effect, discovered by Rudolf Mössbauer (sometimes written "Moessbauer", German: "Mößbauer") in 1958, consists of the nearly recoil-free emission and absorption of nuclear gamma rays in solids. The consequent nuclear spectroscopy method is exquisitely sensitive to small changes in the chemical environment of certain nuclei. Typically, three types of nuclear interactions may be observed: the isomer shift due to differences in nearby electron densities (also called the chemical shift in older literature), quadrupole splitting due to atomic-scale electric field gradients; and magnetic Zeeman splitting due to non-nuclear magnetic fields. Due to the high energy and extremely narrow line widths of nuclear gamma rays, Mössbauer spectroscopy is a highly sensitive technique in terms of energy (and hence frequency) resolution, capable of detecting changes of just a few parts in 1011. It is a me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Spectroscopy
Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functional groups in solid, liquid, or gaseous forms. It can be used to characterize new materials or identify and verify known and unknown samples. The method or technique of infrared spectroscopy is conducted with an instrument called an infrared spectrometer (or spectrophotometer) which produces an infrared spectrum. An IR spectrum can be visualized in a graph of infrared light absorbance (or transmittance) on the vertical axis vs. frequency, wavenumber or wavelength on the horizontal axis. Typical units of wavenumber used in IR spectra are reciprocal centimeters, with the symbol cm−1. Units of IR wavelength are commonly given in micrometers (formerly called "microns"), symbol μm, which are related to the wavenumber in a reciprocal way. A com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutron Diffraction
Neutron diffraction or elastic neutron scattering is the application of neutron scattering to the determination of the atomic and/or magnetic structure of a material. A sample to be examined is placed in a beam of thermal or cold neutrons to obtain a diffraction pattern that provides information of the structure of the material. The technique is similar to X-ray diffraction but due to their different scattering properties, neutrons and X-rays provide complementary information: X-Rays are suited for superficial analysis, strong x-rays from synchrotron radiation are suited for shallow depths or thin specimens, while neutrons having high penetration depth are suited for bulk samples.Measurement of residual stress in materials using neutrons |
X-ray Diffraction
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their crystallographic disorder, and various other information. Since many materials can form crystals—such as salts, metals, minerals, semiconductors, as well as various inorganic, organic, and biological molecules—X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences among various mat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ontario
Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Canada, it is Canada's most populous province, with 38.3 percent of the country's population, and is the second-largest province by total area (after Quebec). Ontario is Canada's fourth-largest jurisdiction in total area when the territories of the Northwest Territories and Nunavut are included. It is home to the nation's capital city, Ottawa, and the nation's most populous city, Toronto, which is Ontario's provincial capital. Ontario is bordered by the province of Manitoba to the west, Hudson Bay and James Bay to the north, and Quebec to the east and northeast, and to the south by the U.S. states of (from west to east) Minnesota, Michigan, Ohio, Pennsylvania, and New York. Almost all of Ontario's border with the United States f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hamilton, Ontario
Hamilton is a port city in the Canadian province of Ontario. Hamilton has a population of 569,353, and its census metropolitan area, which includes Burlington and Grimsby, has a population of 785,184. The city is approximately southwest of Toronto in the Greater Toronto and Hamilton Area (GTHA). Conceived by George Hamilton when he purchased the Durand farm shortly after the War of 1812, the town of Hamilton became the centre of a densely populated and industrialized region at the west end of Lake Ontario known as the Golden Horseshoe. On January 1, 2001, the current boundaries of Hamilton were created through the amalgamation of the original city with other municipalities of the Regional Municipality of Hamilton–Wentworth. Residents of the city are known as Hamiltonians. Traditionally, the local economy has been led by the steel and heavy manufacturing industries. During the 2010s, a shift toward the service sector occurred, such as health and sciences. Hamilton is ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mediterranean
The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the east by the Levant. The Sea has played a central role in the history of Western civilization. Geological evidence indicates that around 5.9 million years ago, the Mediterranean was cut off from the Atlantic and was partly or completely desiccated over a period of some 600,000 years during the Messinian salinity crisis before being refilled by the Zanclean flood about 5.3 million years ago. The Mediterranean Sea covers an area of about , representing 0.7% of the global ocean surface, but its connection to the Atlantic via the Strait of Gibraltar—the narrow strait that connects the Atlantic Ocean to the Mediterranean Sea and separates the Iberian Peninsula in Europe from Morocco in Africa—is only wide. The Mediterranean Sea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elba
Elba ( it, isola d'Elba, ; la, Ilva) is a Mediterranean island in Tuscany, Italy, from the coastal town of Piombino on the Italian mainland, and the largest island of the Tuscan Archipelago. It is also part of the Arcipelago Toscano National Park, and the third largest island in Italy, after Sicily and Sardinia. It is located in the Tyrrhenian Sea about east of the French island of Corsica. The island is part of the province of Livorno and is divided into seven municipalities, with a total population of about 30,000 inhabitants which increases considerably during the summer. The municipalities are Portoferraio (which is also the island's principal town), Campo nell'Elba, Capoliveri, Marciana, Marciana Marina, Porto Azzurro, and Rio. Elba was the site of Napoleon's first exile, from 1814 to 1815. Geography Elba is the largest remaining stretch of land from the ancient tract that once connected the Italian peninsula to Corsica. The northern coast faces the Ligurian Sea, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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