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Austen Angell
Charles Austen Angell (14 December 1933 – 12 March 2021) was a renowned Australian and American physical chemist known for his prolific and highly cited research on the chemistry and physics of glasses and glass-forming liquids. He was internationally recognized as a luminary in the fields of glasses, liquids, water and ionic liquids. His best known contribution is probably the development of the fragility concept and the "strong–fragile" classification of viscous liquids in general. The plot of logarithm of viscosity of liquids of all types to be placed on the same diagram by using the reduced temperature scale with the glass transition temperature Tg as scaling parameter, is widely known as the "Angell plot". He was a pioneer of discovering the extraordinary behavior of supercooled water and launched the modern era of exploring the anomalies of water, which transformed the understanding of the most common substance on Earth in modern physics and chemistry. He was one of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Regents' Professor
Professors in the United States commonly occupy any of several positions of teaching and research within a college or university. In the U.S., the word "professor" informally refers collectively to the academic ranks of assistant professor, associate professor, or professor. This usage differs from the predominant usage of the word professor internationally, where the unqualified word professor only refers to "full professors." The majority of university lecturers and instructors in the United States, , do not occupy these tenure-track ranks, but are part-time adjuncts, or more commonly referred as college teachers. Research and education are among the main tasks of tenured and tenure-track professors, with the amount of time spent on research or teaching depending strongly on the type of institution. Publication of articles in conferences, journals, and books is essential to occupational advancement. As of August 2007, teaching in tertiary educational institutions is one of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian Chemists
Australian(s) may refer to: Australia * Australia, a country * Australians, citizens of the Commonwealth of Australia ** European Australians ** Anglo-Celtic Australians, Australians descended principally from British colonists ** Aboriginal Australians, indigenous peoples of Australia as identified and defined within Australian law * Australia (continent) ** Indigenous Australians * Australian English, the dialect of the English language spoken in Australia * Australian Aboriginal languages * ''The Australian'', a newspaper * Australiana, things of Australian origins Other uses * Australian (horse), a racehorse * Australian, British Columbia, an unincorporated community in Canada See also * The Australian (other) * Australia (other) * * * Austrian (other) Austrian may refer to: * Austrians, someone from Austria or of Austrian descent ** Someone who is considered an Austrian citizen, see Austrian nationality law * Austrian German dialect * Someth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2021 Deaths
This is a list of deaths of notable people, organised by year. New deaths articles are added to their respective month (e.g., Deaths in ) and then linked here. 2022 2021 2020 2019 2018 2017 2016 2015 2014 2013 2012 2011 2010 2009 2008 2007 2006 2005 2004 2003 2002 2001 2000 1999 1998 1997 1996 1995 1994 1993 1992 1991 1990 1989 1988 1987 See also * Lists of deaths by day The following pages, corresponding to the Gregorian calendar, list the historical events, births, deaths, and holidays and observances of the specified day of the year: Footnotes See also * Leap year * List of calendars * List of non-standard ... * Deaths by year {{DEFAULTSORT:deaths by year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science Magazine
''Science'', also widely referred to as ''Science Magazine'', is the peer-reviewed academic journal of the American Association for the Advancement of Science (AAAS) and one of the world's top academic journals. It was first published in 1880, is currently circulated weekly and has a subscriber base of around 130,000. Because institutional subscriptions and online access serve a larger audience, its estimated readership is over 400,000 people. ''Science'' is based in Washington, D.C., United States, with a second office in Cambridge, UK. Contents The major focus of the journal is publishing important original scientific research and research reviews, but ''Science'' also publishes science-related news, opinions on science policy and other matters of interest to scientists and others who are concerned with the wide implications of science and technology. Unlike most scientific journals, which focus on a specific field, ''Science'' and its rival ''Nature (journal), Nature'' c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass Transition
The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials (or in amorphous regions within semicrystalline materials) from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. ISO 11357-2: Plastics – Differential scanning calorimetry – Part 2: Determination of glass transition temperature (1999). An amorphous solid that exhibits a glass transition is called a glass. The reverse transition, achieved by supercooling a viscous liquid into the glass state, is called vitrification. The glass-transition temperature ''T''g of a material characterizes the range of temperatures over which this glass transition occurs (as an experimental definition, typically marked as 100 s of relaxation time). It is always lower than the melting temperature, ''T''m, of the crystalline state of the material, if one exists. Hard plastics like polystyrene and poly(methyl methacrylate) are u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscous Liquid
In condensed matter physics and physical chemistry, the terms viscous liquid, supercooled liquid, and glassforming liquid are often used interchangeably to designate liquids that are at the same time highly viscous (see Viscosity of amorphous materials), can be or are supercooled, and able to form a glass. Working points in glass processing The mechanical properties of glass-forming liquids depend primarily on the viscosity. Therefore, the following working points are defined in terms of viscosity. The temperature is indicated for industrial soda lime glass: Fragile-strong classification In a widespread classification, due to chemist Austen Angell, a glass-forming liquid is called strong if its viscosity approximately obeys an Arrhenius law (log η is linear in 1/''T'' ). In the opposite case of clearly non-Arrhenius behaviour the liquid is called fragile. This classification has no direct relation with the common usage of the word "fragility" to mean brittlene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fragility (glass Physics)
In glass physics, fragility characterizes how rapidly the dynamics of a material slows down as it is cooled toward the glass transition: materials with a higher fragility have a relatively narrow glass transition temperature range, while those with low fragility have a relatively broad glass transition temperature range. Physically, fragility may be related to the presence of dynamical heterogeneity in glasses, as well as to the breakdown of the usual Stokes–Einstein relationship between viscosity and diffusion. Definition Formally, fragility reflects the degree to which the temperature dependence of the viscosity (or relaxation time) deviates from Arrhenius behavior. This classification was originally proposed by Austen Angell. The most common definition of fragility is the "kinetic fragility index" ''m'', which characterizes the slope of the viscosity (or relaxation time) of a material with temperature as it approaches the glass transition temperature from above: :=\ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass-forming Liquid
In condensed matter physics and physical chemistry, the terms viscous liquid, supercooled liquid, and glassforming liquid are often used interchangeably to designate liquids that are at the same time highly viscous (see Viscosity of amorphous materials), can be or are supercooled, and able to form a glass. Working points in glass processing The mechanical properties of glass-forming liquids depend primarily on the viscosity. Therefore, the following working points are defined in terms of viscosity. The temperature is indicated for industrial soda lime glass: Fragile-strong classification In a widespread classification, due to chemist Austen Angell, a glass-forming liquid is called strong if its viscosity approximately obeys an Arrhenius law (log η is linear in 1/''T'' ). In the opposite case of clearly non-Arrhenius behaviour the liquid is called fragile. This classification has no direct relation with the common usage of the word "fragility" to mean brittlenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glass
Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling (quenching) of the molten form; some glasses such as volcanic glass are naturally occurring. The most familiar, and historically the oldest, types of manufactured glass are "silicate glasses" based on the chemical compound silica (silicon dioxide, or quartz), the primary constituent of sand. Soda–lime glass, containing around 70% silica, accounts for around 90% of manufactured glass. The term ''glass'', in popular usage, is often used to refer only to this type of material, although silica-free glasses often have desirable properties for applications in modern communications technology. Some objects, such as drinking glasses and eyeglasses, are so commonly made of silicate-based glass that they are simply called by the name of the material. Despite bei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fragility (glass Physics)
In glass physics, fragility characterizes how rapidly the dynamics of a material slows down as it is cooled toward the glass transition: materials with a higher fragility have a relatively narrow glass transition temperature range, while those with low fragility have a relatively broad glass transition temperature range. Physically, fragility may be related to the presence of dynamical heterogeneity in glasses, as well as to the breakdown of the usual Stokes–Einstein relationship between viscosity and diffusion. Definition Formally, fragility reflects the degree to which the temperature dependence of the viscosity (or relaxation time) deviates from Arrhenius behavior. This classification was originally proposed by Austen Angell. The most common definition of fragility is the "kinetic fragility index" ''m'', which characterizes the slope of the viscosity (or relaxation time) of a material with temperature as it approaches the glass transition temperature from above: :=\ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canberra
Canberra ( ) is the capital city of Australia. Founded following the federation of the colonies of Australia as the seat of government for the new nation, it is Australia's largest inland city and the eighth-largest city overall. The city is located at the northern end of the Australian Capital Territory at the northern tip of the Australian Alps, the country's highest mountain range. As of June 2021, Canberra's estimated population was 453,558. The area chosen for the capital had been inhabited by Indigenous Australians for up to 21,000 years, with the principal group being the Ngunnawal people. European settlement commenced in the first half of the 19th century, as evidenced by surviving landmarks such as St John's Anglican Church and Blundells Cottage. On 1 January 1901, federation of the colonies of Australia was achieved. Following a long dispute over whether Sydney or Melbourne should be the national capital, a compromise was reached: the new capital would be buil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
