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1. Controlling Anisotropy of Quantum-Confined CsPbBr 3 Nanocrystals by Combined Use of Equilibrium and Kinetic Anisotropy

   https://doi.org/10.1021/acs.chemmater.9b01515  

   Dong, Yitong ; Qiao, Tian ; Kim, Doyun ; Rossi, Daniel ; Ahn, Sang Jung ; Son, Dong Hee ( August 2019 , Chemistry of Materials)
2. Crustal Anisotropy from the Birefringence of P-to-S Converted Waves: Bias Associated with P-Wave Anisotropy

   https://doi.org/10.4401/ag-8882  

   Park, Jeffrey ; Chen, Xiaoran ; Levin, Vadim ( January 2023 , Annals of Geophysics)

   Many researchers have used the birefringence of P‑to‑S converted waves from the Moho discontinuity to constrain the anisotropy of Earth’s crust. However, this practice ignores the substantial influence that anisotropy has on the initial amplitude of the converted wave, which adds to the splitting acquired during its propagation from Moho to the seismometer. We find that large variations in Ps birefringence estimates with back-azimuth occur theoretically in the presence of P‑wave anisotropy, which normally accompanies S‑wave anisotropy. The variations are largest for crustal anisotropy with a tilted axis of symmetry, a geometry that is often neglected in birefringence interpretations, but is commonly found in Earth’s crust. We simulated globally-distributed P‑coda datasets for 36 distinct 4‑layer crustal models with combinations of elliptical shear anisotropy or compressional anisotropy, and also incorporated the higher-order anisotropic Backus parameter C. We tested both horizontal and tilted symmetry-axis geometries and tested the birefringence tradeoff associated with Ps converted phases at the top and bottom of a thin high‑ or low‑velocity basal layer. We computed composite receiver functions (RFs) with harmonic regression over back azimuth, using multipletaper correlation with moveout corrections for the epicentral distances of 471 events, to simulate a realistic data set. We estimate Ps birefringence from the radial and transverse RFs, a strategy that is similar to previous studies. We find that Ps splitting can be a useful indicator of bulk crustal anisotropy only under restricted circumstance, either in media with no compressional anisotropy, or if the symmetry axis is horizontal throughout. In other, more-realistic cases, the inferred fast polarization of Ps birefringence estimated from synthetic RFs tends either to drift with back-azimuth, form weak penalty-function minima, or return splitting times that depend on the thickness of an anisotropic layer, rather than the birefringence accumulated within it.  

    

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3. Modification of crustal seismic anisotropy by geological structures (“structural geometric anisotropy”)

   https://doi.org/10.1130/GES01655.1  

   Okaya, David ; Vel, Senthil S. ; Song, Won Joon ; Johnson, Scott E. ( December 2018 , Geosphere)
4. Grain-size-dependent remanence anisotropy and its implications for paleodirections and paleointensities – Proposing a new approach to anisotropy corrections

   https://doi.org/10.1016/j.epsl.2019.01.051  

   Biedermann, Andrea R. ; Bilardello, Dario ; Jackson, Mike ; Tauxe, Lisa ; Feinberg, Joshua M. ( April 2019 , Earth and Planetary Science Letters)
5. Anisotropy of Full and Partial Anhysteretic Remanence Across Different Rock Types: 1—Are Partial Anhysteretic Remanence Anisotropy Tensors Additive?

   https://doi.org/10.1029/2018TC005284  

   Biedermann, Andrea R. ; Jackson, Mike ; Stillinger, Michele D. ; Bilardello, Dario ; Feinberg, Joshua M. ( February 2020 , Tectonics)

   Several types or grain sizes of ferromagnetic minerals can contribute to a rock's remanence and anisotropy of remanence. Each subpopulation may have a different fabric. Measuring anisotropy of partial anhysteretic remanent magnetization (ApARM) allows one to determine the anisotropy contribution of subpopulations with different coercivity distributions. Separating these contributions to remanence anisotropy can provide information about early versus late stages of deformation in fabric studies and is the basis for improved anisotropy corrections in paleomagnetic studies. Unfortunately, collecting multiple ApARM tensors on each specimen is time‐consuming and not often done. Measuring a smaller number of carefully chosen ApARM tensors and obtaining the remaining tensors of interest by tensor calculation would be more efficient. This can only be done, however, when ApARM tensors are additive. Here we investigate the additivity of ApARM tensors in a range of lithologies, by measuring a total of seven ApARM and anisotropy of anhysteretic remanent magnetization (AARM) tensors for each specimen, and comparing the tensors calculated from a combination of ApARM tensors to the corresponding measured AARM. Differences in principal directions between measured and calculated tensors are often smaller than the confidence angles of the measurements. Mean anhysteretic remanences are additive to within ±5%. The anisotropy degree varies by ±30% (k′) or ±0.15 (P), and the shape parameterUby ±0.4. These error limits will help to determine whether or not it is necessary to measure each ApARM tensor in future fabric or paleomagnetic studies, or if these tensors can be calculated from a smaller set of measurements.

    

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