Publications

97. Dong, H., D. He, T. S. Duffy, and Y. Zhao, Elastic moduli and strength of nanocrystalline cubic BC_2 N from x-ray diffraction under nonhydrostatic compression, Physical Review B, 79, 014105, 2009.

96. Jiang, F., G. D. Gwanmesia, T. I. Dyuzheva, and T. S. Duffy, Elasticity of stishovite and acoustic mode softening under high pressure by Brillouin scattering, Physics of the Earth and Planetary Interiors, 172, 235-240, 2009.

95. Mao, Z, S. D. Jacobsen, F. Jiang, J. R. Smyth, C. M. Holl, and T. S. Duffy, Elasticity of hydrous wadsleyite to 12 GPa: Implications for Earth's transition zone, Geophysical Research Letters, 35, L21305, 2008.

94. Jiang, F., J. Majzlan, S. Speziale, D. He, and T. S. Duffy, Single-crystal elasticity of diaspore, AlOOH, to 12 GPa by Brillouin scattering, Physics of the Earth and Planetary Interiors, 170, 220-228, 2008.

93. Duffy, T. S., Some recent advances in understanding the mineralogy of the Earth's deep mantle, Philosophical Transactions of the Royal Society of London A, 366, 4273-4293, 2008.

92. Hirose, K., N. Takafuji, K. Fujino, S. R. Shieh, T. S. Duffy, Iron partitioning between perovskite and post-perovskite: A transmission electron microscope study, American Mineralogist, 93, 1678-1681, 2008.

91. Kubo, A, Y. Wang, C. E. Runge T. Uchida, B. Kiefer, N. Nishiyama, and T. S. Duffy, Melting curve of silicon to 15 GPa determined by two-dimensional angle-dispersive x-ray diffraction using a Kawai-type apparatus with X-ray transparent sintered diamond anvils, Journal of the Physics and Chemistry of Solids, 69, 2255-2260, 2008.

90. Jacobsen, S. D., F. Jiang, Z. Mao, T. S. Duffy, J. R. Smyth, C. M. Holl, D. J. Frost, Effects of hydration on the elastic properties of olivine, Geophysical Research Letters, L14303, 2008.

89. Kubo, A., B. Kiefer, S.-H. Shim, G. Shen, V. B. Prakapenka, and T. S. Duffy, Rietveld structure refinements of MgGeO3 post-perovskite phase to 1 Mbar, American Mineralogist, 93, 965-976, 2008

88. Speziale, S., F. Jiang, Z. Mao, P. J. M. Monteiro, H.-R. Wenk, T. S. Duffy, and F. Schilling, Single-crystal elastic constants of natural ettringite, Cement and Concrete Research, 38, 885-889, 2008

87. Raitses, Y., C. H. Skinner, F. Jiang, and T. S. Duffy, Raman spectroscopy of carbon dust samples from NSTX, Journal of Nuclear Materials, 375, 365-369, 2008.

86. Miyagi, L., N. Nishiyama, Y. Wang, A. Kubo, D. V. West, R. J. Cava, T. S. Duffy, and H.-R. Wenk, Deformation and texture development in CaIrO3 post-perovskite phase to 6 GPa and 1300 K, Earth and Planetary Science Letters, 268, 515-525, 2008.

85. Z. Mao, S. D. Jacobsen, F. Jiang, J. R. Smyth, C. M. Holl, D. J. Frost, and T. S. Duffy, Single-crystal elasticity of wadsleyites, beta-Mg2SiO4, containing 0.37-1.66 wt.% H2O, EPSL, 266, 2008 (Erratum: 268, 540-549, 2008).

84. Duffy, T. S. Mineralogy at the extremes, Nature, 451, 2008.

83. Duffy, T. S., Strength of materials under static loading in the diamond anvil cell, in Shock Compression of Condensed Matter - 2007, edited by M. D. Furnish, M. L. Elert, T. P. Russell, and C. T. White, AIP, New York, 639-644, 2007.

82. Shim, S.-H., A. Kubo, and T. S. Duffy, Raman spectroscopy of perovskite and post-perovskite phases of MgGeO3 to 123 GPa, Earth and Planetary Science Letters, 260, 166-178, 2007.

81. Merkel, S., A. K. McNamara, A. Kubo, S. Speziale, L. Miyagi, Y. Meng, T. S. Duffy, and H.-R. Wenk, Deformation of (Mg,Fe)SiO3 post-perovskite and modeling of D" anisotropy, Science, 316, 1729-1732, 2007. [Supplementary Information] DOI: 10.1126/science.1140609

80. Mao, Z., F. Jiang, and T. S. Duffy, Single-crystal elasticity of zoisite, Ca2Al3Si3O12(OH) , by Brillouin scattering, American Mineralogist, 92, 570-576, 2007. DOI: 10.2138/am.2007.2329

79. Wan, J. T. K., T. S. Duffy, S. Scandolo, and R. Car, First-principles study of density, viscosity, and diffusion coefficients of liquid MgSiO3 at conditions of the Earth's deep mantle, Journal of Geophysical Research, 112, B03208, 2007. DOI: 10.1029/2005JB004135

78. Runge, C. E., A. Kubo, B. Kiefer, Y. Meng, V. Prakapenka, G. Shen, R. J. Cava, and T. S. Duffy, Equation of state of MgGeO3 perovskite to 65 GPa: Comparison with the post-perovskite phase, Physics and Chemistry of Minerals, 33, 699-709, 2006. DOI: 10.1007/s00269-006-0116-8

77. Majzlan, J., S. Speziale, T. S. Duffy, and P. C. Burns, Single-crystal elastic properties of Alunite, KAl3(SO4)2(OH)6, Physics and Chemistry of Minerals, 33, 567-573, 2006. DOI: 10.1007/s00269-006-0104-z

76. Jiang, F., S. Speziale, and T. S. Duffy, Single-crystal elasticity of brucite, Mg(OH)2, to 15 GPa by Brillouin scattering, American Mineralogist, 91, 1893-1900, 2006. DOI: 10.2138/am.2006.2215

75. Kubo, A., B. Kiefer, G. Shen, V. Prakapenka, R. J. Cava, and T. S. Duffy, Stability and equation of state of the post-perovskite phase in MgGeO­3 to 2 Mbar, Geophysical Research Letters, 33, L12S12, 2006. DOI: 10.1029/2006GL025686

74. He, D. W., and T. S. Duffy, X-ray diffraction study of the static strength of tungsten to 69 GPa, Physical Review B, 73, 134106, 2006. DOI: 10.1103/PhysRevB.73.134106

73. Speziale, S., S. R. Shieh, and T. S. Duffy, High-pressure elasticity of calcium oxide: A comparison between Brillouin scattering and radial x-ray diffraction, Journal of Geophysical Research, 111, B02203, 2006. DOI: 10.1029/2005JB003823

72. Shieh, S. R., T. S. Duffy, A. Kubo, G. Shen, V. B. Prakapenka, N. Sata, K. Hirose, and Y. Ohishi, Equation of state of the post-perovskite phase synthesized from a natural (Mg,Fe)SiO3 orthopyroxene, Proceedings of the National Academy of Sciences, 103, 3039-3043, 2006. DOI: 10.1073/pnas.0506811103

71. Merkel, S., A. Kubo, L. Miyagi, S. Speziale, H.-k. Mao, T. S. Duffy, and H.-R. Wenk, Plastic deformation of MgGeO­3 post-perovskite at lower mantle pressures, Science, 311, 644-646, 2006.[Supplementary Information] DOI: 10.1126/science.1121808

70. Shieh, S. R., A. Kubo, T. S. Duffy, V. B. Prakapenka, and G. Shen, High-pressure phases in SnO2 to 117 GPa, Physical Review B, 73, 014105, 2006. DOI: 10.1103/PhysRevB.73.014105

69. Speziale, S., F. Jiang, and T. S. Duffy, Compositional dependence of the elastic wave velocities of mantle minerals: Implications for seismic properties of mantle rocks, in Structure, Composition, and Evolution of Earth's Mantle, edited by R. van der Hilst, J. D. Bass, J. Matas, and J. Trampert, AGU, Washington, DC, 303-323, 2005.

68. Duffy, T. S., Synchrotron facilities and the study of deep planetary interiors, Reports of Progress in Physics, 68, 1811-1859, 2005. DOI: 10.1088/0034-4885/68/8/R03

67. Yin, H., K. D. Hobart, R. L. Peterson, S. R. Shieh, T. S. Duffy, J. C. Sturm, Tunable uniaxial vs biaxial in-plain strain in integrated silicon and silicon-germanium thin films using compliant substrates, Applied Physics Letters, 87, 061922, 2005. DOI: 10.1063/1.2006215

66. Kiefer, B., S. R. Shieh, T. S. Duffy, and T. Sekine, Strength, elasticity, and equation of state of nanocrystalline cubic silicon nitride (c-Si3N4) to 68 GPa, Physical Review B, 72, 014102, 2005. DOI: 10.1103/PhysRevB.72.014102

65. Shieh, S. R., T. S. Duffy, and G. Shen, X-ray diffraction study of phase stability in SiO2 at deep lower mantle conditions, Earth and Planetary Science Letters, 235, 273-282, 2005. DOI: 10.1016/j.espl.2005.04.004

64. Kiefer, B. and T. S. Duffy, Finite element simulations of the laser-heated diamond anvil cell, Journal of Applied Physics, 97, 114902, 2005. DOI: 10.1063/1.1906292

63. Speziale, S., T. S. Duffy, and R. J. Angel, Single-crystal elasticity of fayalite to 12 GPa, Journal of Geophysical Research, 109, B10201, 2004. DOI: 10.1029/2004JB003162

62. He, D. W., S. R. Shieh and T. S. Duffy, Equation of state and strength of boron suboxide from radial x-ray diffraction in a diamond cell under nonhydrostatic compression, Physical Review B, 70, 184121, 2004. DOI: 10.1103/PhysRevB.70.184121

61. Jiang, F., S. Speziale, and T. S. Duffy, Single-crystal elasticity of grossular- and almandine-rich garnets to 11 GPa by Brillouin scattering, Journal of Geophysical Research, 109, B10201, 2004. DOI: 10.1029/2004JB003081

60. Shieh, S. R., T. S. Duffy, and G. Shen, Elasticity and strength of calcium silicate perovskite at lower mantle pressures, Physics of the Earth and Planetary Interiors, 143-144, 93-106, 2004. DOI: 10.1016/j.pepi.2003.10.006

59. Shim, S.-H., T. S. Duffy, R. Jeanloz and G. Shen, Stability and crystal structure of MgSiO3 perovskite to the core-mantle boundary, Geophysical Research Letters, L10603, 2004. DOI: 10.1029/2004GL019639

58. Yin, H. Z., K. D. Hobart, F. J. Kub, S. R. Shieh, T. S. Duffy, J. C. Sturm, High-Ge-content SiGe islands formed on compliant oxide by SiGe oxidation, Applied Physics Letters, 84, 3624-3626, 2004. DOI: 10.1063/1.1738514

57. Shim, S.-H., T. S. Duffy, R. Jeanloz, C.-S. Yoo, and V. Iota, Raman spectroscopy and x-ray diffraction of phase transitions in Cr2O3 to 61 GPa, Physical Review B, 69, 144107, 2004. DOI: 10.1103/PhysRevB.69.144107

56. Jiang, F., S. Speziale, S. R. Shieh, and T. S. Duffy, Single-crystal elasticity of andradite garnet to 11 GPa, Journal of Physics Condensed Matter, 16, S1041-S1052, 2004. DOI: 10.1103/PhysRevB.69.144107

55. Yin, H. Z., R. Huang, K. D. Hobart, J. Liang, Z. Suo, S. R. Shieh, T. S. Duffy, F. J. Kub, and J. C. Sturm, Buckling suppresion of SiGe islands on compliant substrates, Journal of Applied Physics, 94, 6875-6882, 2003. DOI: 10.1063/1.1621069

54. Speziale, S., F. Jiang, C. L. Caylor, S. Kriminski, C.-S. Zha, R. E. Thorne, and T. S. Duffy, Sound velocity and elasticity of tetragonal lysozyme crystals by Brillouin spectroscopy, Biophysical Journal, 85, 3202-3213, 2003.

53. Kavner, A., and T. S. Duffy, Elasticity and rheology of platinum under high pressure and non-hydrostatic stress, Physical Review B, 68, 144101, 2003. DOI: 10.1103/PhysRevB.68.144101

52. Yin, H., K. D. Hobart, F. J. Kub, S. R. Shieh, T. S. Duffy, and J. C. Sturm, Strain partition of Si/SiGe and SiO2/SiGe on compliant substrates, Applied Physics Letters, 82, 3853-3855, 2003. DOI: 10.1063/1.1578168

51. Shim, S.-H., R. Jeanloz, and T. S. Duffy, Tetragonal structure of CaSiO3 perovskite above 20 GPa, Geophysical Research Letters, 2166, 2002. DOI: 10.1029/2002GL016148

50. Shieh, S. R., T. S. Duffy, and B. Li, Strength and Elasticity of SiO2 across the stishovite - CaCl-type structural phase boundary, Physical Review Letters, 89, 25507, 2002. DOI: 10.1103/PhysRevLett.89.255507

49. Shieh, S. R., and T. S. Duffy, Raman spectroscopy of Co(OH)2 to 30 GPa:Implications for amorphization and structural frustration, Physical Review B, 66, 134301, 2002. DOI: 10.1103/PhysRevB.66.134301

48. Shim, S.-H., T. S. Duffy, and K. Takemura, Equation of state of gold and its application to phase boundaries near 660-km depth in Earth's mantle, Earth and Planetary Science Letters, 203, 729-739, 2002. DOI: 10.1016/S0012-821X(02)00917-2 

47. Speziale, S., and T. S. Duffy, Single-crystal elastic constants of fluorite (CaF2) to 9.3 GPa, Physics and Chemistry of Minerals, 29, 465-472, 2002. DOI: 10.1007/s00269-002-0250-x

46. Yin, H., R. Huang, K. D. Hobart, Z. Suo, T. S. Kuan, C. K. Inoki, S. R. Shieh, T. S. Duffy, F. J. Kub, and J. C. Sturm, Strain relaxation of SiGe islands on compliant oxide, Journal of Applied Physics, 92, 9716-9722, 2002. DOI: 10.1063/1.1479757

45. Bo, X.-Z., N. Yao, S. R. Shieh, T. S. Duffy, S. Wagner, and J. C. Sturm, Large-grain polycrystalline silicon films with low intragranular defect density by low-temperature solid-phase crystallization without underlying oxide, Journal of Applied Physics, 91, 2910-2915, 2002. DOI: 10.1063/1.1448395

44. Shim, S.-H. and T. S. Duffy, Raman spectroscopy of Fe2O3 to 62 GPa, American Mineralogist, 87, 318-326, 2002.

43. Shim, S.-H., G. Shen, and T. S. Duffy,Stability and structure of MgSiO3 perovskite to 2300-km depth in the mantle, Science, 293, 2437-2440, 2001.

42. Shim, S.-H., T. S. Duffy, and G. Shen,The post-spinel transformation in Mg2SiO4 and its relation to the 660-km seismic discontinuity, Nature, 411, 571-574, 2001. [Supplementary Information]

41. Kavner, A., and T. S. Duffy, Elasticity and strength of a natural ringwoodite at pressures of the Earth's transition zone, Geophysical Research Letters, 28, 2691-2694, 2001.

40.  Kavner, A., and T. S. Duffy, Pressure-volume-temperature paths in the laser-heated diamond anvil cell, Journal of Applied Physics, 89, 1907-1914, 2001.

39. Kavner, A., T. S. Duffy, and G. Shen, Phase stability and density of FeS at high pressures and temperatures: Implications for the interior structure of Mars, Earth and Planetary Science Letters, 185, 25-33, 2001.

38. Speziale, S., C. S. Zha, T. S. Duffy, R. J. Hemley, and H. K. Mao, Quasi-hydrostatic compression of magnesium oxide to 52 GPa: Implications for the pressure-volume-temperature equation of state, Journal of Geophysical Research, 106, 515-528, 2001.

37. Shim, S.-H., T. S. Duffy, and G. Shen, The stability and pressure-volume-temperature equation of state for CaSiO3 perovskite in the Earth's lower mantle, Journal of Geophysical Research, 105, 25,955-25,968, 2000.

36. Shim, S.-H., T. S. Duffy, and G. Shen, The structure and equation of state of CaSiO3 perovskite at lower mantle pressures and 300 K,Physics of the Earth and Planetary Interiors, 120, 327-338, 2000.

35. Shim, S.-H. and T. S. Duffy, Constraints on the pressure-volume-temperature equation of state of silicate perovskite, American Mineralogist, 85, 354-363, 2000.

34. Duffy, T. S., G. Shen, D. L. Heinz, J. Shu, Y. Ma, R. J. Hemley and H. K. Mao, Lattice strains in gold and rhenium to 37 GPa, Physical Review B, 60, 15063-15073, 1999.

33. Duffy, T. S., G. Shen, J. Shu, R. J. Hemley, and H. K. Mao, Elasticity, strength, and equation of state of gold and molybdenum under non-hydrostatic compression to 25 GPa, Journal of Applied Physics, 86, 6737-6745, 1999.

32. Duffy, T. S. and Y. Wang, Pressure-volume-temperature equations of state, in Ultrahigh Pressure Mineralogy, edited by R. J. Hemley, Reviews in Mineralogy, vol. 37, 425-458, 1998.

31. Zha, C. S., T. S. Duffy, R. T. Downs, H. K. Mao, and R. J. Hemley, Brillouin scattering and X-ray diffraction of San Carlos olivine: Direct pressure determination to 32 GPa, Earth and Planetary Science Letters, 159, 25-34, 1998.

30. Shen, G., H. K. Mao, R. J. Hemley, T. S. Duffy, and M. L. Rivers, Melting and crystal structure of iron at high pressure and temperature, Geophysical Research Letters, 25, 373-376, 1998.

29. Mao, H. K., G. Shen, R. J. Hemley, and T. S. Duffy, X-ray diffraction with a double hot-plate laser-heated diamond cell, in High-Pressure Temperature Research: Properties of Earth and Planetary Materials, edited by M. H. Manghnani and T. Yagi, AGU, Washington, DC, 27-34, 1998.

28. Rivers, M. L, T. S. Duffy, Y. Wang, P. J. Eng, S. R. Sutton, and G. Shen, A new high-pressure research facility at the Advanced Photon Source, in High-Pressure Temperature Research: Properties of Earth and Planetary Materials, edited by M. H. Manghnani and T. Yagi, AGU, Washington, DC, 79-88, 1998.

27. Zha, C. S., T. S. Duffy, H. K. Mao, and R. J. Hemley, Elasticity of the a- and b-polymorphs of Mg2SiO4 at high pressure, in High-Pressure Temperature Research: Properties of Earth and Planetary Materials, edited by M. H. Manghnani and T. Yagi, AGU, Washington, DC, 9-16, 1998.

26. Duffy, T. S. and T. J. Ahrens, Dynamic compression of an Fe-Cr-Ni alloy to 80 GPa, Journal of Applied Physics, 82, 4259-4269, 1997.

25. Zha, C. S., T. S. Duffy, H. K. Mao, R. T. Downs, R. J. Hemley, and D. J. Weidner, Single-crystal elasticity of
 b -Mg2SiO4 to the pressure of the 410-km seismic discontinuity in the Earth's mantle, Earth and Planetary Science Letters, 147, E9-E15, 1997.

24. Zha, C. S., Duffy, T. S., R. T. Downs, H. K. Mao, and R. J. Hemley, Sound velocity and elasticity of single-crystal forsterite to 16 GPa, Journal of Geophysical Research, 101, 17,535-17,546, 1996.

23. Downs, R. T., C. S. Zha, T. S. Duffy, and L. W. Finger, Equation of state of forsterite to 17.2 GPa and the effects of pressure media, American Mineralogist, 81, 51-55, 1996.

22. Duffy, T. S., C. S. Zha, R. T. Downs, H. K. Mao, and R. J. Hemley, Elasticity of forsterite to 16 GPa and the composition of the upper mantle, Nature, 378, 170-173, 1995.

21. Duffy, T. S., J. Shu, H. K. Mao, and R. J. Hemley, Single-crystal x-ray diffraction of brucite to 14 GPa, Physics and Chemistry of Minerals, 22, 277-281, 1995.

20. Hemley, R. J., H. K. Mao, T. S. Duffy, J. H. Eggert, A. F. Goncharev, M. Hanfland, M. Li, M. Somayazulu, W. L. Vos, and C. S. Zha, Dense hydrogen in the outer solar system: Implications from recent high-pressure experiments, in Volatiles in the Earth and Solar System, edited by K. A. Farley, American Institute of Physics, New York, NY, 250-260, 1995.

19. Duffy, T. S., R. J. Hemley, and H. K. Mao, Structure and bonding in hydrous minerals at high pressure: Raman spectroscopy of alkaline earth hydroxides, in Volatiles in the Earth and Solar System, edited by K. A. Farley, American Institute of Physics, New York, NY, 211-220, 1995.

18. Duffy, T. S. and R. J. Hemley, Some like it hot: The temperature structure of the earth, Reviews of Geophysics, 33, supplement, part 1, 5-10, 1995.

17. Duffy, T. S., C. Meade, Y. Fei, H. K. Mao, and R. J. Hemley, A high-pressure phase transition in brucite Mg(OH)2, American Mineralogist, 80, 222-230, 1995.

16. Duffy, T. S., R. J. Hemley, and H. K. Mao, Equation of state and shear strength of magnesium oxide to 227 GPa, Physical Review Letters, 74, 1371-1374, 1995.

15. Sekine, T., T. S. Duffy, A. M. Rubin, W. W. Anderson, and T. J. Ahrens, Shock compression and isentropic release of granite, Geophysical Journal International, 20, 247-261, 1995.

14. Duffy, T. S. and T. J. Ahrens, Compressional sound velocity, equation of state, and constitutive response of shock-compressed magnesium oxide, Journal of Geophysical Research, 100, 529-542, 1995.

13. Zha, C. S., R. J. Hemley, H. K. Mao, T. S. Duffy, and C. Meade, Acoustic velocities and refractive index of SiO2 glass to 57.5 GPa by Brillouin scattering, Physical Review B, 50, 13,105-13,112, 1994.

12. Duffy, T. S. and T. J. Ahrens, Dynamic response of molybdenum shock compressed at 1400 °C, Journal of Applied Physics, 76, 835-842, 1994.

11. Duffy, T. S., W. L. Vos, C. S. Zha, R. J. Hemley, and H. K. Mao, Sound velocities in dense hydrogen and the interior of Jupiter, Science, 263, 1590-1593, 1994.

10. Duffy, T. S. and T. J. Ahrens, The temperature sensitivity of elastic wave velocity at high pressure: New results for molybdenum, Geophysical Research Letters, 21, 473-476, 1994.

9. Zha, C. S., T. S. Duffy, H. K. Mao, and R. J. Hemley, Elasticity of hydrogen to 24 GPa from single-crystal Brillouin scattering and synchrotron x-ray diffraction, Physical Review B, 48, 9246-9255, 1993.

8. Duffy, T. S. and T. J. Ahrens, Thermal expansion of mantle and core materials at very high pressure and temperature, Geophysical Research Letters, 20, 1103-1106, 1993.

7. Duffy, T. S. and T. J. Ahrens, Lateral variation in lower mantle seismic velocities, in High-Pressure Research in Mineral Physics: Applications to Earth and Planetary Sciences, edited by Y. Syono and M. H. Manghnani, Terra Scientific, Tokyo, 197-206, 1992.

6. Duffy, T. S. and T. J. Ahrens, Hugoniot sound velocities in metals with applications to the Earth's inner core, in High-Pressure Research in Mineral Physics: Applications to Earth and Planetary Sciences, edited by Y. Syono and M. H. Manghnani, Terra Scientific, Tokyo, 353-362, 1992.

5. Duffy, T. S. and T. J. Ahrens, Sound velocities at high temperature and pressure and their geophysical implications, Journal of Geophysical Research, 97, 4503-4520, 1992.

4. Tyburczy, J. A., T. S. Duffy, T. J. Ahrens, and M. A. Lange, Shock wave equation of state of serpentine to 150 GPa: Implications for the occurrence of water in the Earth's lower mantle, Journal of Geophysical Research, 96, 18,011-18,028, 1991.

3. Duffy, T. S., T. J. Ahrens, and M. A. Lange, The shock wave equation of state of brucite Mg(OH)2 Journal of Geophysical Research, 96, 14,319-14,330, 1991.

2. Duffy, T. S. and D. L. Anderson, Seismic velocities in mantle minerals and the mineralogy of the upper mantle, Journal of Geophysical Research, 94, 1895-1912, 1989.

1. Duffy, T. S. and M. T. Vaughan, Elasticity of enstatite and its relationship to crystal structure, Journal of Geophysical Research, 93, 383-391, 1988.


 

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