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Methyl- and phenylhydrazines react with 2-(diphenylacetyl)-1,3-indandione ( 1 ) to yield respectively the 1-(methylhydrazone) and the 1-(phenylhydrazone) of 2-(diphenylacetyl)-1,3-indandione ( 2a and 2b ). In comparison, acetic and benzoic acid hydrazides react with 1 to give respectively the α-(acetylhydrazone) and the α-(benzoylhydrazone) of 2-(diphenylacetyl)-1,3-indandione ( 3a and 3b ). Cyclization of 2a and 2b gives 2,3-disubstituted indeno[1,2-c]pyrazol-4(2H)-ones ( 7a and 7b ). Cyclization of 3a and 3b , followed by methylation, gives 1-methyl- and 2-methyl-3-(diphenylmethyl)indeno[1,2-c]pyrazol-4(1 and 2H)-ones ( 9a and 9b ). 2-Isovaleryl-1,3-indandione reacts with phenylhydrazine to give directly 3-isobutyl-1-phenylindeno[1,2-c]-pyrazol-4(1H)-one ( 10 ). 相似文献
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W. Y. Lu M. F. Horstemeyer J. S. Korellis R. B. Grishabar D. Mosher 《Theoretical and Applied Fracture Mechanics》1998,30(2):139-152
Experiments were designed to determine the failure characteristics of AISI 304L stainless steel under different stress triaxialities and temperatures up to 70% of melt. The data show that as temperature increases the displacement to failure of notched tensile specimens increases. The complex interaction of deformation mechanisms, such as twinning and dynamic recrystallization, appears to negate the damage accumulation at higher temperatures. Microstructural analyses and finite element simulations indicate that voids nucleate, grow, and coalesce more rapidly as temperature and triaxiality increase. Finite element simulations were performed to analyze temperature dependence on the Cocks–Ashby void growth model. The finite element simulations qualitatively show a double-knee that was observed in the notched experimental specimens after loading. The combined experimental–numerical study indicates that failure can be defined at several points in the notch tests when: (1) macrovoids starts to form, (2) the load drop-off occurs, and (3) total perforation of the specimen occurs. These three points occur simultaneously in ambient conditions but occur at different displacements at higher temperatures. 相似文献
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Low energy, variable angle, electron-impact energy-loss spectra of nitromethane have been obtained. A previously unreported singlet → triplet excitation with maximum intensity at 3.8 eV energy loss is observed and its relevance to the gas phase photochemistry of nitromethane is discussed. An additional weak transition with maximum intensity at 4.45 eV energy loss is tentatively assigned to a symmetry-forbidden transition. 相似文献
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Harry S. Mosher 《Tetrahedron》1974,30(13):1733-1745
Methods for the synthesis, determination of enantiomeric purity and absolute configuration of primary 1-deuterio alcohols (RCHDOH) are outlined and tabulated. Studies on the rearrangements, solvolyses and SN2 reactions of chiral neopentyl-1-d derivatives are reviewed. Finally, the optical rotatory properties of the (CH3)3CCHDX compounds, with their unique symmetry properties, are summarized and discussed. 相似文献