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*    Paper on CaCO3 aragonite by Ying Li et al. accepted by Am Min; See Am Min

*    New paper by Xuebing Wang on of KLB-1 peridotite to 10 GPa in GRL makes a record in highest pressure of velocity measurement on mantle “rocks”! see GRL website

*    New paper on hexagonal NbN by Yongtao Zou et al. now accepted by Scientific Reports

*    Dr. Liebermann gave two invited lectures at University of Hawaii, highlighting research conducted by our graduate students Xuebing Wang, Ting Chen, and Xintong Qi.

*    Graduate students Xuebing Wang, Ting Chen, and Xintong Qi presented posters at DOE/SSAP 2015 Annual Symposium. 

*    Earth Planet. Sci. Lett. paper by T. Chen et al. (2015). Anomalous behavior of SiO2 coesite can be potentially the cause of X-discontinuity! see EPSL website

*    Dr. Linlin Chang from University of CAS joins ultrasonic group as a visiting scholar.

*    Postdoc Yongtao Zou takes an Associate Professor in Jilin University! Congrats!  

*    2014 Fall AGU,  Graduate students Xuebing Wang and Ting Chen presented posters.

*    Dr. Yaron Greeberg from Israel (Physics Dept., NRCN, Israel) joins the ultrasonic group as a visiting scholar.  

*    New minerals named “Liebermannite”in honor of our Bob, Congratulations!

*    2013 Fall AGU Three presentations led by Xuebing Wang, Ting Chen and Yongtao Zou, respectively, Great job!

*    Shear Anomalies in MgAl2O4 Spinel at High Pressure :Direct measurement of P and S wave velocities of MgAl2O4 Spinel at 14 GPa 900 K revealed anomalous behavior in shear properties. See publication by Dr. Yongtao Zou in Journal of Physical Chemistry (C ).

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*      Congratulations to Bob Liebermann for AGU Edward A. Flinn III Award!

    Link to AGU Website for the Announcement

 

*    Origin of Thermal and Compositional Heterogeneities in the Lower Mantle The relative changes between shear and compressional velocities (RSP=∂lnVS/∂lnVP), bulk sound and shear velocities(RCS = ∂lnVC/∂ln VS), and density versus shear wave velocity (RrS=∂ lnr/∂lnVS) in response to thermal and chemical variations were investigated for pyrolitic lower mantle. Negative values of RrS and RCS are indicative of chemical anomalies in the lower mantle, but a combination of thermal and chemical heterogeneities may be required to produce velocity and density anomalies at the magnitudes observed in seismic data. (link to Li, B. Progress in Natural Science 19,1603-1611)

       

*    Equation of State of Bulk Metallic Glass: Compressional (VP) and shear wave (VS) velocities of Zr46Cu37.6Ag8.4Al8 bulk metallic glass (BMG) have been measured up to 6.3 GPa at room temperature using ultrasonic interferometry in conjunction with synchrotron x-radiography. The densities at high pressures are uniquely determined using the measured velocities. This work is supported by DOE/NNSA. Details: Liu, Wei, Q. Zeng, Q. Jiang, Liping Wang, and Baosheng Li (2011) Density and elasticity of Zr46Cu37.6Ag8.4Al8 bulk metallic glass at high pressure, Scripta Materialia 65, 497-500. 

 

*    Thermal Equation of State of CaIrO3 Post-Perovskite

The pressure–volume–temperature (P–V–T) relation of CaIrO3 post-perovskite (ppv) was measured up to 8.6 GPa and 1273 K. Unit-cell dimensions were derived from the LeBail full profile refinement technique, and the results were fitted using the third-order Birth-Murnaghan equation of state. The derived bulk modulus KT0 at ambient pressure and temperature is 168.3 ± 7.1 GPa with a pressure derivative KT ‘ = 5.4 (7). High temperature data are fitted using the high-temperature Birch-Murnaghan equation of state, the thermal pressure approach, and the Mie-Gru¨neisen-Debye formalism. This work is supported by NSF/Geophysics-Geochemistry.  Liu, W., Whitaker, M., Q. Liu, N. Nishiyama, Y. Wang, A. Kubo, T. Duffy, B. Li, (2011) Thermal Equation of State of CaIrO3 Post-Perovskite, Phys. Chem. Min, DOI: 10.1007/s00269-010-0414-z)


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