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Contributors
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- By Mitchell Aboulafia, Frederick Adams, Marilyn McCord Adams, Robert M. Adams, Laird Addis, James W. Allard, David Allison, William P. Alston, Karl Ameriks, C. Anthony Anderson, David Leech Anderson, Lanier Anderson, Roger Ariew, David Armstrong, Denis G. Arnold, E. J. Ashworth, Margaret Atherton, Robin Attfield, Bruce Aune, Edward Wilson Averill, Jody Azzouni, Kent Bach, Andrew Bailey, Lynne Rudder Baker, Thomas R. Baldwin, Jon Barwise, George Bealer, William Bechtel, Lawrence C. Becker, Mark A. Bedau, Ernst Behler, José A. Benardete, Ermanno Bencivenga, Jan Berg, Michael Bergmann, Robert L. Bernasconi, Sven Bernecker, Bernard Berofsky, Rod Bertolet, Charles J. Beyer, Christian Beyer, Joseph Bien, Joseph Bien, Peg Birmingham, Ivan Boh, James Bohman, Daniel Bonevac, Laurence BonJour, William J. Bouwsma, Raymond D. Bradley, Myles Brand, Richard B. Brandt, Michael E. Bratman, Stephen E. Braude, Daniel Breazeale, Angela Breitenbach, Jason Bridges, David O. Brink, Gordon G. Brittan, Justin Broackes, Dan W. Brock, Aaron Bronfman, Jeffrey E. Brower, Bartosz Brozek, Anthony Brueckner, Jeffrey Bub, Lara Buchak, Otavio Bueno, Ann E. Bumpus, Robert W. Burch, John Burgess, Arthur W. Burks, Panayot Butchvarov, Robert E. Butts, Marina Bykova, Patrick Byrne, David Carr, Noël Carroll, Edward S. Casey, Victor Caston, Victor Caston, Albert Casullo, Robert L. Causey, Alan K. L. Chan, Ruth Chang, Deen K. Chatterjee, Andrew Chignell, Roderick M. Chisholm, Kelly J. Clark, E. J. Coffman, Robin Collins, Brian P. Copenhaver, John Corcoran, John Cottingham, Roger Crisp, Frederick J. Crosson, Antonio S. Cua, Phillip D. Cummins, Martin Curd, Adam Cureton, Andrew Cutrofello, Stephen Darwall, Paul Sheldon Davies, Wayne A. Davis, Timothy Joseph Day, Claudio de Almeida, Mario De Caro, Mario De Caro, John Deigh, C. F. Delaney, Daniel C. Dennett, Michael R. DePaul, Michael Detlefsen, Daniel Trent Devereux, Philip E. Devine, John M. Dillon, Martin C. Dillon, Robert DiSalle, Mary Domski, Alan Donagan, Paul Draper, Fred Dretske, Mircea Dumitru, Wilhelm Dupré, Gerald Dworkin, John Earman, Ellery Eells, Catherine Z. Elgin, Berent Enç, Ronald P. Endicott, Edward Erwin, John Etchemendy, C. Stephen Evans, Susan L. Feagin, Solomon Feferman, Richard Feldman, Arthur Fine, Maurice A. Finocchiaro, William FitzPatrick, Richard E. Flathman, Gvozden Flego, Richard Foley, Graeme Forbes, Rainer Forst, Malcolm R. Forster, Daniel Fouke, Patrick Francken, Samuel Freeman, Elizabeth Fricker, Miranda Fricker, Michael Friedman, Michael Fuerstein, Richard A. Fumerton, Alan Gabbey, Pieranna Garavaso, Daniel Garber, Jorge L. A. Garcia, Robert K. Garcia, Don Garrett, Philip Gasper, Gerald Gaus, Berys Gaut, Bernard Gert, Roger F. Gibson, Cody Gilmore, Carl Ginet, Alan H. Goldman, Alvin I. Goldman, Alfonso Gömez-Lobo, Lenn E. Goodman, Robert M. Gordon, Stefan Gosepath, Jorge J. E. Gracia, Daniel W. Graham, George A. Graham, Peter J. Graham, Richard E. Grandy, I. Grattan-Guinness, John Greco, Philip T. Grier, Nicholas Griffin, Nicholas Griffin, David A. Griffiths, Paul J. Griffiths, Stephen R. Grimm, Charles L. Griswold, Charles B. Guignon, Pete A. Y. Gunter, Dimitri Gutas, Gary Gutting, Paul Guyer, Kwame Gyekye, Oscar A. Haac, Raul Hakli, Raul Hakli, Michael Hallett, Edward C. Halper, Jean Hampton, R. James Hankinson, K. R. Hanley, Russell Hardin, Robert M. Harnish, William Harper, David Harrah, Kevin Hart, Ali Hasan, William Hasker, John Haugeland, Roger Hausheer, William Heald, Peter Heath, Richard Heck, John F. Heil, Vincent F. Hendricks, Stephen Hetherington, Francis Heylighen, Kathleen Marie Higgins, Risto Hilpinen, Harold T. Hodes, Joshua Hoffman, Alan Holland, Robert L. Holmes, Richard Holton, Brad W. Hooker, Terence E. Horgan, Tamara Horowitz, Paul Horwich, Vittorio Hösle, Paul Hoβfeld, Daniel Howard-Snyder, Frances Howard-Snyder, Anne Hudson, Deal W. Hudson, Carl A. Huffman, David L. Hull, Patricia Huntington, Thomas Hurka, Paul Hurley, Rosalind Hursthouse, Guillermo Hurtado, Ronald E. Hustwit, Sarah Hutton, Jonathan Jenkins Ichikawa, Harry A. Ide, David Ingram, Philip J. Ivanhoe, Alfred L. Ivry, Frank Jackson, Dale Jacquette, Joseph Jedwab, Richard Jeffrey, David Alan Johnson, Edward Johnson, Mark D. Jordan, Richard Joyce, Hwa Yol Jung, Robert Hillary Kane, Tomis Kapitan, Jacquelyn Ann K. Kegley, James A. Keller, Ralph Kennedy, Sergei Khoruzhii, Jaegwon Kim, Yersu Kim, Nathan L. King, Patricia Kitcher, Peter D. Klein, E. D. Klemke, Virginia Klenk, George L. Kline, Christian Klotz, Simo Knuuttila, Joseph J. Kockelmans, Konstantin Kolenda, Sebastian Tomasz Kołodziejczyk, Isaac Kramnick, Richard Kraut, Fred Kroon, Manfred Kuehn, Steven T. Kuhn, Henry E. Kyburg, John Lachs, Jennifer Lackey, Stephen E. Lahey, Andrea Lavazza, Thomas H. Leahey, Joo Heung Lee, Keith Lehrer, Dorothy Leland, Noah M. Lemos, Ernest LePore, Sarah-Jane Leslie, Isaac Levi, Andrew Levine, Alan E. Lewis, Daniel E. Little, Shu-hsien Liu, Shu-hsien Liu, Alan K. L. Chan, Brian Loar, Lawrence B. Lombard, John Longeway, Dominic McIver Lopes, Michael J. Loux, E. J. Lowe, Steven Luper, Eugene C. Luschei, William G. Lycan, David Lyons, David Macarthur, Danielle Macbeth, Scott MacDonald, Jacob L. Mackey, Louis H. Mackey, Penelope Mackie, Edward H. Madden, Penelope Maddy, G. B. Madison, Bernd Magnus, Pekka Mäkelä, Rudolf A. Makkreel, David Manley, William E. Mann (W.E.M.), Vladimir Marchenkov, Peter Markie, Jean-Pierre Marquis, Ausonio Marras, Mike W. Martin, A. P. Martinich, William L. McBride, David McCabe, Storrs McCall, Hugh J. McCann, Robert N. McCauley, John J. McDermott, Sarah McGrath, Ralph McInerny, Daniel J. McKaughan, Thomas McKay, Michael McKinsey, Brian P. McLaughlin, Ernan McMullin, Anthonie Meijers, Jack W. Meiland, William Jason Melanson, Alfred R. Mele, Joseph R. Mendola, Christopher Menzel, Michael J. Meyer, Christian B. Miller, David W. Miller, Peter Millican, Robert N. Minor, Phillip Mitsis, James A. Montmarquet, Michael S. Moore, Tim Moore, Benjamin Morison, Donald R. Morrison, Stephen J. Morse, Paul K. Moser, Alexander P. D. Mourelatos, Ian Mueller, James Bernard Murphy, Mark C. Murphy, Steven Nadler, Jan Narveson, Alan Nelson, Jerome Neu, Samuel Newlands, Kai Nielsen, Ilkka Niiniluoto, Carlos G. Noreña, Calvin G. Normore, David Fate Norton, Nikolaj Nottelmann, Donald Nute, David S. Oderberg, Steve Odin, Michael O’Rourke, Willard G. Oxtoby, Heinz Paetzold, George S. Pappas, Anthony J. Parel, Lydia Patton, R. P. Peerenboom, Francis Jeffry Pelletier, Adriaan T. Peperzak, Derk Pereboom, Jaroslav Peregrin, Glen Pettigrove, Philip Pettit, Edmund L. Pincoffs, Andrew Pinsent, Robert B. Pippin, Alvin Plantinga, Louis P. Pojman, Richard H. Popkin, John F. Post, Carl J. Posy, William J. Prior, Richard Purtill, Michael Quante, Philip L. Quinn, Philip L. Quinn, Elizabeth S. Radcliffe, Diana Raffman, Gerard Raulet, Stephen L. Read, Andrews Reath, Andrew Reisner, Nicholas Rescher, Henry S. Richardson, Robert C. Richardson, Thomas Ricketts, Wayne D. Riggs, Mark Roberts, Robert C. Roberts, Luke Robinson, Alexander Rosenberg, Gary Rosenkranz, Bernice Glatzer Rosenthal, Adina L. Roskies, William L. Rowe, T. M. Rudavsky, Michael Ruse, Bruce Russell, Lilly-Marlene Russow, Dan Ryder, R. M. Sainsbury, Joseph Salerno, Nathan Salmon, Wesley C. Salmon, Constantine Sandis, David H. Sanford, Marco Santambrogio, David Sapire, Ruth A. Saunders, Geoffrey Sayre-McCord, Charles Sayward, James P. Scanlan, Richard Schacht, Tamar Schapiro, Frederick F. Schmitt, Jerome B. Schneewind, Calvin O. Schrag, Alan D. Schrift, George F. Schumm, Jean-Loup Seban, David N. Sedley, Kenneth Seeskin, Krister Segerberg, Charlene Haddock Seigfried, Dennis M. Senchuk, James F. Sennett, William Lad Sessions, Stewart Shapiro, Tommie Shelby, Donald W. Sherburne, Christopher Shields, Roger A. Shiner, Sydney Shoemaker, Robert K. Shope, Kwong-loi Shun, Wilfried Sieg, A. John Simmons, Robert L. Simon, Marcus G. Singer, Georgette Sinkler, Walter Sinnott-Armstrong, Matti T. Sintonen, Lawrence Sklar, Brian Skyrms, Robert C. Sleigh, Michael Anthony Slote, Hans Sluga, Barry Smith, Michael Smith, Robin Smith, Robert Sokolowski, Robert C. Solomon, Marta Soniewicka, Philip Soper, Ernest Sosa, Nicholas Southwood, Paul Vincent Spade, T. L. S. Sprigge, Eric O. Springsted, George J. Stack, Rebecca Stangl, Jason Stanley, Florian Steinberger, Sören Stenlund, Christopher Stephens, James P. Sterba, Josef Stern, Matthias Steup, M. A. Stewart, Leopold Stubenberg, Edith Dudley Sulla, Frederick Suppe, Jere Paul Surber, David George Sussman, Sigrún Svavarsdóttir, Zeno G. Swijtink, Richard Swinburne, Charles C. Taliaferro, Robert B. Talisse, John Tasioulas, Paul Teller, Larry S. Temkin, Mark Textor, H. S. Thayer, Peter Thielke, Alan Thomas, Amie L. Thomasson, Katherine Thomson-Jones, Joshua C. Thurow, Vzalerie Tiberius, Terrence N. Tice, Paul Tidman, Mark C. Timmons, William Tolhurst, James E. Tomberlin, Rosemarie Tong, Lawrence Torcello, Kelly Trogdon, J. D. Trout, Robert E. Tully, Raimo Tuomela, John Turri, Martin M. Tweedale, Thomas Uebel, Jennifer Uleman, James Van Cleve, Harry van der Linden, Peter van Inwagen, Bryan W. Van Norden, René van Woudenberg, Donald Phillip Verene, Samantha Vice, Thomas Vinci, Donald Wayne Viney, Barbara Von Eckardt, Peter B. M. Vranas, Steven J. Wagner, William J. Wainwright, Paul E. Walker, Robert E. Wall, Craig Walton, Douglas Walton, Eric Watkins, Richard A. Watson, Michael V. Wedin, Rudolph H. Weingartner, Paul Weirich, Paul J. Weithman, Carl Wellman, Howard Wettstein, Samuel C. Wheeler, Stephen A. White, Jennifer Whiting, Edward R. Wierenga, Michael Williams, Fred Wilson, W. Kent Wilson, Kenneth P. Winkler, John F. Wippel, Jan Woleński, Allan B. Wolter, Nicholas P. Wolterstorff, Rega Wood, W. Jay Wood, Paul Woodruff, Alison Wylie, Gideon Yaffe, Takashi Yagisawa, Yutaka Yamamoto, Keith E. Yandell, Xiaomei Yang, Dean Zimmerman, Günter Zoller, Catherine Zuckert, Michael Zuckert, Jack A. Zupko (J.A.Z.)
- Edited by Robert Audi, University of Notre Dame, Indiana
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- The Cambridge Dictionary of Philosophy
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- 05 August 2015
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- 27 April 2015, pp ix-xxx
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Contributors
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- By Lenard A. Adler, Pinky Agarwal, Rehan Ahmed, Jagga Rao Alluri, Fawaz Al-Mufti, Samuel Alperin, Michael Amoashiy, Michael Andary, David J. Anschel, Padmaja Aradhya, Vandana Aspen, Esther Baldinger, Jee Bang, George D. Baquis, John J. Barry, Jason J. S. Barton, Julius Bazan, Amanda R. Bedford, Marlene Behrmann, Lourdes Bello-Espinosa, Ajay Berdia, Alan R. Berger, Mark Beyer, Don C. Bienfang, Kevin M. Biglan, Thomas M. Boes, Paul W. Brazis, Jonathan L. Brisman, Jeffrey A. Brown, Scott E. Brown, Ryan R. Byrne, Rina Caprarella, Casey A. Chamberlain, Wan-Tsu W. Chang, Grace M. Charles, Jasvinder Chawla, David Clark, Todd J. Cohen, Joe Colombo, Howard Crystal, Vladimir Dadashev, Sarita B. Dave, Jean Robert Desrouleaux, Richard L. Doty, Robert Duarte, Jeffrey S. Durmer, Christyn M. Edmundson, Eric R. Eggenberger, Steven Ender, Noam Epstein, Alberto J. Espay, Alan B. Ettinger, Niloofar (Nelly) Faghani, Amtul Farheen, Edward Firouztale, Rod Foroozan, Anne L. Foundas, David Elliot Friedman, Deborah I. Friedman, Steven J. Frucht, Oded Gerber, Tal Gilboa, Martin Gizzi, Teneille G. Gofton, Louis J. Goodrich, Malcolm H. Gottesman, Varda Gross-Tsur, Deepak Grover, David A. Gudis, John J. Halperin, Maxim D. Hammer, Andrew R. Harrison, L. Anne Hayman, Galen V. Henderson, Steven Herskovitz, Caitlin Hoffman, Laryssa A. Huryn, Andres M. Kanner, Gary P. Kaplan, Bashar Katirji, Kenneth R. Kaufman, Annie Killoran, Nina Kirz, Gad E. Klein, Danielle G. Koby, Christopher P. Kogut, W. Curt LaFrance, Patrick J.M. Lavin, Susan W. Law, James L. Levenson, Richard B. Lipton, Glenn Lopate, Daniel J. Luciano, Reema Maindiratta, Robert M. Mallery, Georgios Manousakis, Alan Mazurek, Luis J. Mejico, Dragana Micic, Ali Mokhtarzadeh, Walter J. Molofsky, Heather E. Moss, Mark L. Moster, Manpreet Multani, Siddhartha Nadkarni, George C. Newman, Rolla Nuoman, Paul A. Nyquist, Gaia Donata Oggioni, Odi Oguh, Denis Ostrovskiy, Kristina Y. Pao, Juwen Park, Anastas F. Pass, Victoria S. Pelak, Jeffrey Peterson, John Pile-Spellman, Misha L. Pless, Gregory M. Pontone, Aparna M. Prabhu, Michael T. Pulley, Philip Ragone, Prajwal Rajappa, Venkat Ramani, Sindhu Ramchandren, Ritesh A. Ramdhani, Ramses Ribot, Heidi D. Riney, Diana Rojas-Soto, Michael Ronthal, Daniel M. Rosenbaum, David B. Rosenfield, Durga Roy, Michael J. Ruckenstein, Max C. Rudansky, Eva Sahay, Friedhelm Sandbrink, Jade S. Schiffman, Angela Scicutella, Maroun T. Semaan, Robert C. Sergott, Aashit K. Shah, David M. Shaw, Amit M. Shelat, Claire A. Sheldon, Anant M. Shenoy, Yelizaveta Sher, Jessica A. Shields, Tanya Simuni, Rajpaul Singh, Eric E. Smouha, David Solomon, Mehri Songhorian, Steven A. Sparr, Egilius L. H. Spierings, Eve G. Spratt, Beth Stein, S.H. Subramony, Rosa Ana Tang, Cara Tannenbaum, Hakan Tekeli, Amanda J. Thompson, Michael J. Thorpy, Matthew J. Thurtell, Pedro J. Torrico, Ira M. Turner, Scott Uretsky, Ruth H. Walker, Deborah M. Weisbrot, Michael A. Williams, Jacques Winter, Randall J. Wright, Jay Elliot Yasen, Shicong Ye, G. Bryan Young, Huiying Yu, Ryan J. Zehnder
- Edited by Alan B. Ettinger, Albert Einstein College of Medicine, New York, Deborah M. Weisbrot, State University of New York, Stony Brook
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- Neurologic Differential Diagnosis
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- 05 June 2014
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- 17 April 2014, pp xi-xx
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Key bird species of Marojejy Strict Nature Reserve, Madagascar
- M. I. Evans, J. W. Duckworth, A. F. A. Hawkins, R. J. Safford, B. C. Sheldon, R. J. Wilkinson
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- Journal:
- Bird Conservation International / Volume 2 / Issue 3 / September 1992
- Published online by Cambridge University Press:
- 11 May 2010, pp. 201-220
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From mid-August to late October 1988, Marojejy Strict Nature Reserve, in the northern part of Madagascar's rainforest, was surveyed for birds. The reserve extends from 75 to 2,133 m altitude and the 60,150 ha comprise an almost intact series of altitudinal forest zones. Observations were made in all forest zones and at all altitudes of the reserve and the total of 104 species found included almost all Madagascan rainforest birds, making Marojejy one of the most important sites for bird conservation in Madagascar. The status of the eight threatened, 10 near-threatened and two restricted-range species observed is detailed here, together with notes on their ecology and behaviour. Finds of major conservation interest included the first documented sighting of Madagascar Serpent-eagle Eutriorchis astur since 1930, a healthy population of Henst's Goshawk Accipiter henstü, all four rainforest ground-rollers Brachypteracüdae and a new population of Yellow-bellied Sunbird-asity Neodrepanis hypoxantha. Furthermore, the patchy distribution of Helmetbird Euryceros prevostü urges reconsideration of its current assessment as not at risk. Four threatened species (Rufous-headed Ground-roller Atelornis crossleyi, Yellow-bellied Sun-bird-asity, Grey-crowned Greenbul Phyllastrephus cinereiceps and Madagascar Yellowbrow Crossleyia xanthophrys) were found only in the upper montane forests; this apparent altitudinal preference for three of these species had not been suggested before this survey. The major threat to the birds of Marojejy is the ceaseless piecemeal clearance of the reserve's forest, which is proceeding inwards from the boundary.
De la mi-aout a la fin octobre 1988, une etude sur les oiseaux a été menee dans la Reserve Naturelle Integrate de Marojejy, situee dans le nord de la foret equatoriale de Madagascar. La reserve s'etend sur une altitude allant de 75 a 2,133 metres et sa superficie de 60,150 ha abrite une serie de forets d'altitude restees pratiquement intactes. Des observations ont 6te faites dans toutes les zones foresrieres et a toutes les altitudes de cette reserve et les 104 especes d'oiseaux trouvees incluaient presque toutes les especes d'oiseaux de la foret tropicale de Madagascar, la reserve de Marojejy representant ainsi l'un des sites de conservation des oiseaux les plus importants de Madagascar. La situation des huit especes menacees, dix especes presque menacees et deux especes a distribution geographique limitee, observees au cours de l'etude, est decrite ici en detail, avec des notes sur leur ecologie et leur comportement.
Parmi les decouvertes particulierement interessantes pour la conservation, nous pouvons citer la premiere observation documented de l'aigle-autour Eutriorchis astur depuis 1930, une population bien developpee de Accipiter henstü, l'ensemble des quatre types forestieres de Brachypteracüdae et une nouvelle population de Neodrepanis hypoxan-tha. De plus, la repartition geographique inegale de YEuryceros prevostü exige une reconsideration urgente de son evaluation actuelle en tant qu'espece sans risque. Quatre especes menacees (Atelornis crossleyi, Neodrepanis hypoxantha, Phyllastrephus cinereiceps et Crossleyia xanthophrys) n'ont été trouvees que dans les forets de haute altitude: l'apparente preference de ces trois especes pour les hautes altitudes n'avait pas été suggeree avant cette etude. La principale menace pour les oiseaux de Marojejy est le defrichage incessant de la foret de la reserve, cette destruction s'etendant progressive-ment de l'exterieur vers l'interieur de la foret.
Fission-track dating of British Ordovician and Silurian stratotypes
- R. J. Ross, Jr, C. W. Naeser, G. A. Izett, J. D. Obradovich, M. G. Bassett, C. P. Hughes, L. R. M. Cocks, W. T. Dean, J. K. Ingham, C. J. Jenkins, R. B. Rickards, P. R. Sheldon, P. Toghill, H. B. Whittington, J. Zalasiewicz
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- Journal:
- Geological Magazine / Volume 119 / Issue 2 / March 1982
- Published online by Cambridge University Press:
- 01 May 2009, pp. 135-153
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Fission-track dating of zircons and apatites from tuffs and bentonites has produced the first isotopic ages for the type sections of the Ordovician and Silurian Systems. In the Ordovician the following ages have been determined: lower Arenig 493 Ma, lower Llanvirn 487 Ma, lower Llandeilo 477 Ma, upper Caradoc 463 Ma and upper Ashgill 434 Ma. In the Silurian, the following: lower Llandovery 437 Ma, lower Wenlock 422 Ma, upper Wenlock 414 Ma and Ludlow 407 Ma. The Ordovician-Silurian boundary is interpreted as occurring at about 436 Ma. Three North American Rocklandian bentonites yielded zircons whose ages average 453 Ma. This is about 10 Ma younger than supposedly correlative units in the British type sections.
Optimization of chemical vapor infiltration with simultaneous powder formationa)
- A. Ditkowski, D. Gottlieb, B. W. Sheldon
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- Journal:
- Journal of Materials Research / Volume 15 / Issue 12 / December 2000
- Published online by Cambridge University Press:
- 31 January 2011, pp. 2695-2705
- Print publication:
- December 2000
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A key difficulty in isothermal, isobaric chemical vapor infiltration is the long processing times that are typically required. With this in mind, it was important to minimize infiltration times. This optimization problem was addressed here, using a relatively simple model for dilute gases. The results provided useful asymptotic expressions for the minimum time and corresponding conditions. These approximations were quantitatively accurate for most cases of interest, where relatively uniform infiltration was required. They also provided useful quantitative insight in cases where less uniformity was required. The effects of homogeneous nucleation were also investigated. This does not effect the governing equations for infiltration of a porous body; however, powder formation can restrict the range of permissible infiltration conditions. This was analyzed for the case of carbon infiltration from methane.
Grain Impingement and Intrinsic Stresses in CVD Diamond
- S. Nijhawan, J. Rankin, B. L Walden, B. W. Sheldon
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- Journal:
- MRS Online Proceedings Library Archive / Volume 505 / 1997
- Published online by Cambridge University Press:
- 10 February 2011, 415
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- 1997
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Intrinsic stresses in polycrystalline CVD diamond films have been related to restructuring at grain boundaries. It is speculated that reducing the interfacial energy induces an elastic tensile strain. There appears to be a correlation between the evolution of macroscopic stresses in the entire sample and localized, non-homogeneous stresses in the microstructure based on Raman Spectroscopy and x-ray diffraction pole figures. A multistep processing sequence developed previously can help reduce these stresses substantially, by using an intermediate annealing step when the diamond grains are partially coalesced. Our results suggest that small changes in the film microstructure due to annealing can reduce both homogeneous and non-homogeneous stresses.
The Control Of Intrinsic Stresses In Cvd Diamond Films With Multistep Processing
- S. Nijhawan, S. M. Jankovsky, B. W. Sheldon
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- Journal:
- MRS Online Proceedings Library Archive / Volume 416 / 1995
- Published online by Cambridge University Press:
- 10 February 2011, 163
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- 1995
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The role of intrinsic stresses in diamond films is examined. The films were deposited on (100) Si substrates by microwave plasma-enhanced chemical vapor deposition. The total internal stresses (thermal and intrinsic) were measured at room temperature with the bending plate method. The thermal stresses are compressive and arise due to the mismatch in thermal expansion coefficient of film and substrate. The intinsic stresses were tensile and evolved during the deposition process. These stresses increased with increasing deposition time. A 12 hour intermediate annealing treatment was found to reduce the tensile stresses considerably. The annealing treatment is most effective when the diamond crystallites are undergoing impingement and coalescence. This is consistent with the theory that the maximum tensile stresses are associated with grain boundary energetics.
Light-Scattering Measurements of CVD Silicon Carbide
- B. W. Sheldon, T. M. Besmann
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- Journal:
- MRS Online Proceedings Library Archive / Volume 168 / 1989
- Published online by Cambridge University Press:
- 21 February 2011, 99
- Print publication:
- 1989
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Surface morphologies created by the chemical vapor deposition (CVD) of silicon carbide were examined with light scattering. Silicon carbide was deposited from methyltrichlorosilane under various conditions to create different surfaces. A helium neon laser was used, and the scattered light was measured over a range of scattering angles. These measurements are compared with scanning electron microscopy (SEM) observations and profilometer measurements of the same surfaces. In theory the scattered light contains all of the information needed to provide a statistical description of a given surface; however, a complete vector theory for the scattering phenomena is too complex to provide any simple basis for experimental analysis. The application and limits of existing descriptions of scattering from a rough surface are discussed.
Characterization Of Ceramic Matrix Composites Fabricated By Chemical Vapor Infiltration
- D. P. Stinton, D. M. Hembree, JR., K. L. More, B. W. Sheldon, T. M. Besmann
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- Journal:
- MRS Online Proceedings Library Archive / Volume 168 / 1989
- Published online by Cambridge University Press:
- 21 February 2011, 273
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- 1989
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A process for the preparation of fiber-reinforced SiC composites by chemical vapor deposition has been developed at Oak Ridge National Laboratory. Composites are prepared by infiltrating fibrous preforms with reactant gases that decompose at elevated temperatures to deposit silicon carbide between and around the fibers. Because the infiltration process utilizes both temperature and pressure gradients, SiC is deposited under conditions that vary considerably from the hot face to the cool face of the composite. Matrix characterization of composite samples by transmission electron microscopy and Raman spectroscopy are described.