Sample records for crowfoot
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NASA Astrophysics Data System (ADS)
Montalvo, Jessica
2009-10-01
Born in 1910 in Cairo, Egypt, Dorothy Crowfoot Hodgkin would later be known as the third woman in history to win the Nobel Prize in Chemistry for her research on the structure of vitamin B-12. Her X-ray crystallography work also included discovering the molecular structure of penicillin and insulin. Dr. Hodgkin's work has aided in determining the structures of molecules for others to expand the technology necessary for today's medicine.
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NASA Technical Reports Server (NTRS)
Lee, S. C. S.
1979-01-01
Three weaves were evaluated; a balanced plain weave, a balanced 8-harness satin weave, and a semiunidirectional crowfoot satin weave. The current state-of-the-art resin system selected was Fiberite's 934 Epoxy; the advanced resin systems evaluated were Phenolic, Phenolic/Novolac, Benzyl and Bismaleimide. The panels were fabricated for testing on NASA/Ames Research Center's Composites Modification Program. Room temperature mechanical tests only were performed by Hitco; the results are presented.
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Solar cell and I.C. aspects of ingot-to-slice mechanical processing
NASA Astrophysics Data System (ADS)
Dyer, L. D.
1985-08-01
Intensive efforts have been put into the growth of silicon crystals to suit today's solar cell and integrated circuit requirements. Each step of processing the crystal must also receive concentrated attention to preserve the grown-in perfection and to provide a suitable device-ready wafer at reasonable cost. A comparison is made between solar cell and I.C. requirements on the mechanical processing of silicon from ingot to wafer. Specific defects are described that can ruin the slice or can possibly lead to device degradation. These include grinding cracks, saw exit chips, crow's-foot fractures, edge cracks, and handling scratches.
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Solar cell and I.C. aspects of ingot-to-slice mechanical processing
NASA Technical Reports Server (NTRS)
Dyer, L. D.
1985-01-01
Intensive efforts have been put into the growth of silicon crystals to suit today's solar cell and integrated circuit requirements. Each step of processing the crystal must also receive concentrated attention to preserve the grown-in perfection and to provide a suitable device-ready wafer at reasonable cost. A comparison is made between solar cell and I.C. requirements on the mechanical processing of silicon from ingot to wafer. Specific defects are described that can ruin the slice or can possibly lead to device degradation. These include grinding cracks, saw exit chips, crow's-foot fractures, edge cracks, and handling scratches.
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Nye, Mary Jo
2014-08-01
Patterns of collaboration and co-authorship in chemical science from the 1920s to the 1960s are examined with an eye to frequency of co-authorship and differences in allocation of credit during a period of increasing team research and specialization within chemical research groups. Three research leaders in the cross-disciplinary and cutting edge field of X-ray crystallography and molecular structure are the focus of this historical study within a framework of sociological literature on different collaborative patterns followed by eminent scientists. The examples of Michael Polanyi in Berlin and Manchester, Linus Pauling in Pasadena, and Dorothy Crowfoot Hodgkin in Oxford demonstrate the need to de-centre historical narrative from the heroic 'he' or 'she' to the collaborative 'they.' These cases demonstrate, too, the roles of disciplinary apprenticeships, local conditions, and individual personalities for historical explanation that transcends universal generalizations about scientific practice, material culture, and sociological trends.
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House of Commons committee releases report on Canada's drug strategy.
Jürgens, Ralf
2002-12-01
On 17 May 2001, the House of Commons created a Special Committee on Non-Medical Use of Drugs based on a motion introduced by Randy White, Canadian Alliance MP (Langley-Abbottsford) and gave it a very broad mandate to study "the factors underlying or relating to the non-medical use of drugs in Canada" and to propose recommendations aimed at reducing "the dimensions of the problem involved in such use." In December 2002, the Committee released its report, entitled Policy for the New Millennium: Working Together to Redefine Canada's Drug Strategy. The report contains many good recommendations, but fails to deal adequately with the fundamental harms caused by Canada's drug laws and federal government inaction. Far better is the supplementary report written by NDP MP Libby Davies (Vancouver East), which contains an excellent, informed critique of the report. The supplementary report from the official opposition, written by MPs Randy White and Kevin Sorenson (Crowfoot, Alberta) also makes for interesting, if troubling, reading--it is based nearly exclusively on fiction rather than facts and science.
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2017-01-01
The development of structure-guided drug discovery is a story of knowledge exchange where new ideas originate from all parts of the research ecosystem. Dorothy Crowfoot Hodgkin obtained insulin from Boots Pure Drug Company in the 1930s and insulin crystallization was optimized in the company Novo in the 1950s, allowing the structure to be determined at Oxford University. The structure of renin was developed in academia, on this occasion in London, in response to a need to develop antihypertensives in pharma. The idea of a dimeric aspartic protease came from an international academic team and was discovered in HIV; it eventually led to new HIV antivirals being developed in industry. Structure-guided fragment-based discovery was developed in large pharma and biotechs, but has been exploited in academia for the development of new inhibitors targeting protein–protein interactions and also antimicrobials to combat mycobacterial infections such as tuberculosis. These observations provide a strong argument against the so-called ‘linear model’, where ideas flow only in one direction from academic institutions to industry. Structure-guided drug discovery is a story of applications of protein crystallography and knowledge exhange between academia and industry that has led to new drug approvals for cancer and other common medical conditions by the Food and Drug Administration in the USA, as well as hope for the treatment of rare genetic diseases and infectious diseases that are a particular challenge in the developing world. PMID:28875019
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Providing a Turn for the Better
NASA Technical Reports Server (NTRS)
2004-01-01
Engineers are tasked with designing new systems every day to meet changing or unexpected technical requirements. After the tragic explosion of the Space Shuttle Challenger on January 28, 1986, NASA engineers embarked on a complete overhaul of many of their long-standing quality systems and procedures. When the official cause of the accident was determined to be an O-ring failure in the right Solid Rocket Booster, NASA's Shuttle Program initiated a thorough redesign of the rocket boosters' clevis ends, which are the O-ring's mating surfaces. One of the unique systems that NASA engineers developed as a result of this effort included a heating assembly that is coupled to the outside of the rocket boosters. When the assembly is affixed to the external surface of the boosters, the very nature of its design allows for the warming of the O-rings prior to launch. After the engineers completed the assembly's design, however, they found that it was nearly impossible to tighten the spanner nuts required for attaching the system, given the minimum amount of clearance they had in the limited and confined space. Under these circumstances, the standard wrenches typically used for tightening these types of nuts did not work, and there were no other existing devices to solve the problem. NASA engineers embraced the challenge, developing a torque wrench tool adapter that allowed for a full rotation of spanner nuts in confined spaces. The tool, which is similar to an open-ended crowfoot wrench and a fixed-face spanner wrench, contains two dowel pins that center and lock the wrench onto the nut.
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NASA Astrophysics Data System (ADS)
Byers, Nina; Williams, Gary
2006-08-01
Foreword Freeman J. Dyson; Introduction Nina Byers; 1. Hertha Aryton 1854-1923 Joan Mason; 2. Margaret Maltby 1860-1944 Peggy Kidwell; 3. Agnes Pockels 1862-1935 Gary A. Williams; 4. Marie Curie 1867-1934 A. Pais; 5. Henrietta Leavitt 1868-1921 Jean L. Turner; 6. Harriet Brooks 1876-1933 C. W. Wong; 7. Lise Meitner 1878-1968 Ruth Lewin Sime; 8. Emmy Noether 1882-1935 Nina Byers; 9. Inge Lehmann 1888-1993 Bruce A. Bolt; 10. Marietta Blau 1894-1970 Leopold Halpern and Maurice M. Shapiro; 11. Hertha Sponer 1895-1968 Helmut Rechenberg; 12. Irene Joliot-Curie 1897-1956 Hélène Langevin-Joliot and Pierre Radvanyi; 13. Katherine Burr Blodgett 1898-1979 Gary A. Williams; 14. Cecilia Payne Gaposchkin 1900-1979 Vera C. Rubin; 15. Mary Cartwright 1900-1998 Freeman J. Dyson; 16. Bertha Jeffreys 1903-1999 Ruth M. Williams; 17. Kathleen Yardley Lonsdale1903-1971 Judith Milledge; 18. Maria Goeppert Mayer 1906-1972 Steven A. Moszkowski; 19. Helen Megaw 1907-2002 A. Michael Glazer and Christine Kelsey; 20. Yvette Cauchois 1908-1999 Christiane Bonnelle; 21. Marguerite Perey 1909-1975 Jean-Pierre Adloff and George B. Kauffman; 22. Dorothy Crowfoot Hodgkin 1910-1994 Jenny P. Glusker; 23. Gertrude Scharff Goldhaber 1911-1998 Alfred Scharff Goldhaber; 24. Chien Shiung Wu 1912-1997 Noemie Bencze-Koller; 25. Margaret E. Burbidge 1919 Virginia Trimble; 26. Phyllis Freier 1921-1992 Cecil J. Waddington; 27. Rosalyn S. Yalow 1921 M. S. Dresselhaus and F. A. Stahl; 28. Esther Conwell 1922 Lewis Rothberg; 29. Cecile Dewitt-Morette 1922 Bryce DeWitt; 30. Yvonne Choquet-Bruhat 1923 James W. York Jr.; 31. Vera Rubin 1928 Robert J. Rubin; 32. Mildred S. Dresselhaus 1930 G. Dresselhaus and F. A. Stahl; 33. Myriam Sarachik 1933 Jonathan R. Friedman; 34. Juliet Lee-Franzini 1933 Paolo Franzini; 35. Helen T. Edwards 1936 John Peoples; 36. Mary K. Gaillard 1939 Andreszej Buras; 37. Renata Kallosh 1943 Andrei Linde and Michael Gutperle; 38. Jocelyn Bell Burnell 1943 Ferdinand V. Coroniti and Gary A. Williams; 39. Gail G. Hanson 1947 David G. Cassel; 40. San Lan Wu David B. Cline.
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NASA Astrophysics Data System (ADS)
Byers, Nina; Williams, Gary
2010-12-01
Foreword Freeman J. Dyson; Introduction Nina Byers; 1. Hertha Aryton 1854-1923 Joan Mason; 2. Margaret Maltby 1860-1944 Peggy Kidwell; 3. Agnes Pockels 1862-1935 Gary A. Williams; 4. Marie Curie 1867-1934 A. Pais; 5. Henrietta Leavitt 1868-1921 Jean L. Turner; 6. Harriet Brooks 1876-1933 C. W. Wong; 7. Lise Meitner 1878-1968 Ruth Lewin Sime; 8. Emmy Noether 1882-1935 Nina Byers; 9. Inge Lehmann 1888-1993 Bruce A. Bolt; 10. Marietta Blau 1894-1970 Leopold Halpern and Maurice M. Shapiro; 11. Hertha Sponer 1895-1968 Helmut Rechenberg; 12. Irene Joliot-Curie 1897-1956 Hélène Langevin-Joliot and Pierre Radvanyi; 13. Katherine Burr Blodgett 1898-1979 Gary A. Williams; 14. Cecilia Payne Gaposchkin 1900-1979 Vera C. Rubin; 15. Mary Cartwright 1900-1998 Freeman J. Dyson; 16. Bertha Jeffreys 1903-1999 Ruth M. Williams; 17. Kathleen Yardley Lonsdale1903-1971 Judith Milledge; 18. Maria Goeppert Mayer 1906-1972 Steven A. Moszkowski; 19. Helen Megaw 1907-2002 A. Michael Glazer and Christine Kelsey; 20. Yvette Cauchois 1908-1999 Christiane Bonnelle; 21. Marguerite Perey 1909-1975 Jean-Pierre Adloff and George B. Kauffman; 22. Dorothy Crowfoot Hodgkin 1910-1994 Jenny P. Glusker; 23. Gertrude Scharff Goldhaber 1911-1998 Alfred Scharff Goldhaber; 24. Chien Shiung Wu 1912-1997 Noemie Bencze-Koller; 25. Margaret E. Burbidge 1919 Virginia Trimble; 26. Phyllis Freier 1921-1992 Cecil J. Waddington; 27. Rosalyn S. Yalow 1921 M. S. Dresselhaus and F. A. Stahl; 28. Esther Conwell 1922 Lewis Rothberg; 29. Cecile Dewitt-Morette 1922 Bryce DeWitt; 30. Yvonne Choquet-Bruhat 1923 James W. York Jr.; 31. Vera Rubin 1928 Robert J. Rubin; 32. Mildred S. Dresselhaus 1930 G. Dresselhaus and F. A. Stahl; 33. Myriam Sarachik 1933 Jonathan R. Friedman; 34. Juliet Lee-Franzini 1933 Paolo Franzini; 35. Helen T. Edwards 1936 John Peoples; 36. Mary K. Gaillard 1939 Andreszej Buras; 37. Renata Kallosh 1943 Andrei Linde and Michael Gutperle; 38. Jocelyn Bell Burnell 1943 Ferdinand V. Coroniti and Gary A. Williams; 39. Gail G. Hanson 1947 David G. Cassel; 40. San Lan Wu David B. Cline.
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Chemical Achievers: The Human Face of the Chemical Sciences (by Mary Ellen Bowden)
NASA Astrophysics Data System (ADS)
Kauffman, George B.
1999-02-01
Chemical Heritage Foundation: Philadelphia, PA, 1997. viii + 180 pp. 21.6 x 27.8 cm. ISBN 0-941901-15-1. Paper. 20.00 (10.00 for high school teachers who provide documentation). At a 1991 summer workshop sponsored by the Chemical Heritage Foundation and taught by Derek A. Davenport and William B. Jensen, high school and college teachers of introductory chemistry requested a source of pictorial material about famous chemical scientists suitable as a classroom aid. CHF responded by publishing this attractive, inexpensive paperback volume, which reflects the considerable research effort needed to locate appropriate images and to write the biographical essays. Printed on heavy, glossy paper and spiral bound to facilitate conversion to overhead transparencies, it contains 157 images from pictorial collections at CHF and many other institutions on two types of achievers: the historical "greats" most often referred to in introductory courses, and scientists who made contributions in areas of the chemical sciences that are of special relevance to modern life and the career choices students will make. The pictures are intended to provide the "human face" of the book's subtitle- "to point to the human beings who had the insights and made the major advances that [teachers] ask students to master." Thus, for example, Boyle's law becomes less cold and abstract if the student can connect it with the two portraits of the Irish scientist even if his face is topped with a wig. Marie Curie can be seen in the role of wife and mother as well as genius scientist in the photographs of her with her two daughters, one of whom also became a Nobel laureate. And students are reminded of the ubiquity of the contribution of the chemical scientists to all aspects of our everyday life by the stories and pictures of Wallace Hume Carothers' path to nylon, Percy Lavon Julian's work on hormones, and Charles F. Chandler and Rachel Carson's efforts to preserve the environment. In addition to portraits (formal and informal, familiar and unfamiliar), caricatures, apparatus, patent drawings, models, manuscripts, memoranda, laboratories, and plants and buildings are featured. The book presents many images of chemists in the work settings where they actually made their discoveries. The quaint pictures of Chandler with his wash bottle, William H. Walker with his slide rule, Carl Djerassi peering at a flask without goggle protection, and Edward Goodrich Acheson with his omnipresent cigar evoke a bygone era that will induce nostalgia in instructors and curiosity or disbelief in students. Many of the 80 featured chemists are minority scientists; 10 are women (Dorothy Crowfoot Hodgkin, Marie Curie, Iréne Joliot-Curie, Mme. Lavoisier, Rosalind Franklin, Stephanie L. Kwolek, Ellen Swallow Richards, Alice Hamilton, Rachel Carson, and Julia Brainerd Hall, whose role in her brother Charles Martin Hall's development of the electrolytic production of metal is underappreciated), and three are African-Americans (Percy Lavon Julian, Walter Lincoln Hawkins, and Henry Aaron Hill). The book's 11 sections, each prefaced with a short, helpful summary, and the number of scientists profiled in each are Forerunners, 4; Theory and Production of Gases, 4; Electrochemistry and Electrochemical Industries, 12; The Path to the Periodic Table, 9; Atomic and Nuclear Structure, 9; Chemical Synthesis, Structure, and Bonding, 9; Pharmaceuticals and the Path to Biomolecules, 10; Petroleum and Petrochemicals, 4; Plastics and Other Polymers, 6; Chemical Engineering (most of whose practitioners were unfamiliar to me), 6; and Human and Natural Environmental Concerns, 7. An extensive bibliography (five double-column pages), arranged according to these sections, includes books, articles, dissertations, collections, and oral histories. Items as recent as 1997 and even a 1998 book in press are cited. An index (three triple-column pages) facilitates location of material. Chemical Achievers is to some extent similar to Henry Monmouth Smith's long-out-of-print Torchbearers of Chemistry (Academic Press, 1949), but the quality of the illustrations and paper are much better and the text is much more detailed. The book is virtually error-free; the only one that I spotted was the misspelling of O. Bertrand Ramsay's name as Ramsey.