Fe, C 0.75 (wt%) steel, quenched, martensitic and quench cracks
The steel has been rapidly quenched. This leads to a rapid volume change due to thermal expansion. In this case the steel has been unable to plastically deform to accommodate this change. This leads to the nucleation of cracks in the metal. This is exacerbated by the fact that the quenching of steel promotes the formation of the brittle phase martensite.
Author(s): Dr R F Cochrane, Department of Materials, Universi

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Al 88, Si 12 (wt%), eutectic alloy
This alloy is of the eutectic composition. From the melt a eutectic is formed between aluminium solid solution and virtually pure silicon. Slow solidification produces a very coarse microstructure. The eutectic comprises large plates of silicon in the aluminium matrix. This microstructure displays poor ductility due to the brittleness of large silicon plates. The microstructure is normally refined through either rapid solidification, which lets the silicon phase assume a fibrous form, or by a pr
Author(s): Prof T W Clyne, Department of Materials Science an

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Al 88, Si 12 (wt%), eutectic alloy
This sample is a casting alloy of eutectic composition. From the melt a eutectic is formed between aluminium solid solution and virtually pure silicon. Slow solidification produces a very coarse microstructure. The eutectic comprises large plates of silicon in the aluminium matrix. This microstructure displays poor ductility due to the brittleness of large silicon plates. The microstructure is normally refined through either rapid solidification, which lets the silicon phase assume a fibrous for
Author(s): Prof T W Clyne, Department of Materials Science an

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IN718 nickel-based superalloy held for 3 hours at 850°C
IN718 is a nickel-based superalloy composed of approximately 53 wt% Ni, 19 wt% Fe, 18 wt% Cr, 5 wt% Nb, and small amounts of Ti, Mo, Co, and Al. The alloy has a number of distinct phases present in its microstructure. These are namely the matrix, γ, and the precipitates, γ', γ'', and δ. The primary strengthening phase is γ'' [1], the composition of which is Ni3Nb. It has a body-centred tetragonal structure, and forms semi-coherently as disc-shaped platelets within the γ matrix, having thre
Author(s): R Guest, Rolls-Royce University Technology Centre,

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IN718 nickel-based superalloy held for 1 minute at 850°C
IN718 is a nickel-based superalloy composed of approximately 53 wt% Ni, 19 wt% Fe, 18 wt% Cr, 5 wt% Nb, and small amounts of Ti, Mo, Co, and Al. The alloy has a number of distinct phases present in its microstructure. These are namely the matrix, γ, and the precipitates, γ', γ'', and δ. The primary strengthening phase is γ'' [1], the composition of which is Ni3Nb. It has a body-centred tetragonal structure, and forms semi-coherently as disc-shaped platelets within the γ matrix, having thre
Author(s): R Guest, Rolls-Royce University Technology Centre,

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IN718 nickel-based superalloy held for 24 hours at 850°C
IN718 is a nickel-based superalloy composed of approximately 53 wt% Ni, 19 wt% Fe, 18 wt% Cr, 5 wt% Nb, and small amounts of Ti, Mo, Co, and Al. The alloy has a number of distinct phases present in its microstructure. These are namely the matrix, γ, and the precipitates, γ', γ'', and δ. The primary strengthening phase is γ'' [1], the composition of which is Ni3Nb. It has a body-centred tetragonal structure, and forms semi-coherently as disc-shaped platelets within the γ matrix, having thre
Author(s): R Guest, Rolls-Royce University Technology Centre,

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IN718 nickel-based superalloy held for 48 hours at 850°C
IN718 is a nickel-based superalloy composed of approximately 53 wt% Ni, 19 wt% Fe, 18 wt% Cr, 5 wt% Nb, and small amounts of Ti, Mo, Co, and Al. The alloy has a number of distinct phases present in its microstructure. These are namely the matrix, γ, and the precipitates, γ', γ'', and δ. The primary strengthening phase is γ'' [1], the composition of which is Ni3Nb. It has a body-centred tetragonal structure, and forms semi-coherently as disc-shaped platelets within the γ matrix, having thre
Author(s): R Guest, Rolls-Royce University Technology Centre,

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Peace Corps 50th Anniversary 2 A.M. Celebrations, Steps of Michigan Union
A 2 a.m. October 14, 2010 celebration of the remarks by John Kennedy 50 years ago, that led to the formation of the Peace Corps.
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Peace Corps 50th anniversary 11 A.M. Celebrations, Steps of Michigan Union
The 11 a.m., October 14, 2010, celebration of the remarks by John Kennedy that led to the formation of the Peace Corps 50 years earlier.
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Fe, C 2, Mn 0.7 (wt%) steel, quenched, producing martensite
This steel was quenched from the austenite phase field too rapidly for carbon to diffuse out and form cementite. This resulted in the formation of the brittle martensite phase.
Author(s): Dr R F Cochrane, Department of Materials, Universi

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Mohatma Gandhi Biography
Mahatma Gandhi, the pre-eminent political and spiritual leader of India and the Indian independence movement, is the subject of this video. This fast paced work is a biography of his later life and how he worked to advocate non-violence as a way for change. The video shows the power of civil disobedience. A religious radical kills Gandhi. (04:12)
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Breaking Up is Hard to Do
The collapse of the Soviet State in 1991 was followed by Chechen President Dzhokhar Dudayev's declaration of the Chechen Republic's independence from Moscow. Concerned over the loss of its territorial integrity, Russian troops invaded the breakaway republic and a civil war ensued. In l996, Chechen rebels regained control of the capital, Grozny, from Russian forces, almost destroying the city in the process. Fighting in Chechnya continues to this day, although on a relatively smaller scale. The W
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Lyle Lane discusses mutual exchange program between United States and Cuba
Eduardo Diaz asks Lyle Lane, Chief, US Interest Section, if the United States government is trying to work out a way in which Cuban Americans can visit their families in Cuba. He feels it is an area that will be mutually beneficial to both countries, and hope to encourage the formation of a more regular ...
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The Phenology Handbook
A guide to phenological monitoring for students, teachers, families, and nature enthusiasts. Phenology is the observation and measurement of events in time. The passing of the seasons is one of the most familiar phenomena on Earth. Consider, for example, the onset of spring in temperate climates. As winter ends, our surroundings burst with new life — forest canopies fill with vibrant greens, flocks of birds migrate in formation to northern breeding grounds, and brilliant wildflowers and their
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The Association of Tetrameric Acetylcholinesterase with ColQ Tail: A Block Normal Mode Analysis
Acetylcholinesterase (AChE) rapidly hydrolyzes acetylcholine in the neuromuscular junctions and other cholinergic synapses to terminate the neuronal signal. In physiological conditions, AChE exists as tetramers associated with the proline-rich attachment domain (PRAD) of either collagen-like Q subunit ...
Author(s): dzhang

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Writing conventions
Examples of common errors in sentence formation, usage, and mechanics.
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The Age of Revolutions (1776-1989?) - European Civilization from the Renaissance to the Present
An introduction to European history from around 1500 to the present. The central question that the course addresses is how and why Europe-- a small, relatively poor, and politically fragmented place-- became the motor of globalization and a world civilization in its won right. Put differently how did �western� become an adjective that, for better and often for worse, stands in place of �modern.� Our approach will be broadly cultural, i.e. it approaches politics, economics, social life,
Author(s): Thomas Laqueur

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The Enlightenment: Daring to Know and its Difficulties - European Civilization from the Renaissance
An introduction to European history from around 1500 to the present. The central question that the course addresses is how and why Europe-- a small, relatively poor, and politically fragmented place-- became the motor of globalization and a world civilization in its won right. Put differently how did �western� become an adjective that, for better and often for worse, stands in place of �modern.� Our approach will be broadly cultural, i.e. it approaches politics, economics, social life,
Author(s): Thomas Laqueur

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Water: The Flow of Women's Work
helps students compare the division of labor around water-related work in their own homes to families in rural Lesotho to gain an understanding of the multiple factors influencing gender role formation.
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The Mysterious Life of Caves
This is a companion website to a NOVA television series investigating strange life-forms found in toxic caverns. The program reviews the traditional theory of cave formation; introduces new theories of microbial sulfuric acid production; examines the role of oil-feeding microbes in dissolving limestone; presents the discovery of microbes in caves that live solely on chemical nutrients; and reviews other extreme environments. The site offers an interview with a microbiologist, an essay by a caver
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