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   https://doi.org/10.1021/acs.inorgchem.9b02719  

   Boreen, Michael A.; Lussier, Daniel J.; Skeel, Brighton A.; Lohrey, Trevor D.; Watt, Fabian A.; Shuh, David K.; Long, Jeffrey R.; Hohloch, Stephan; Arnold, John (November 2019, Inorganic Chemistry)
2. Conversion of Trivalent Uranium Anilido to Tetravalent Uranium Imido Species via Oxidative Deprotonation

   https://doi.org/10.1021/acs.inorgchem.0c01704  

   Perales, Diana; Ford, Shannon A.; Salpage, Sahan R.; Collins, Tyler S.; Zeller, Matthias; Hanson, Kenneth; Bart, Suzanne C. (September 2020, Inorganic Chemistry)

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3. Uranium–Thorium Dating of Speleothems

   https://doi.org/10.2138/gselements.17.2.87  

   Wendt, Kathleen A.; Li, Xianglei; Edwards, R. Lawrence (April 2021, Elements)

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   Speleothems are important timekeepers of Earth’s climate history. A key advantage of speleothems is that they can be dated using U–Th techniques. Mass spectrometric methods for measuring U and Th isotopes has led to vast improvements in measurement precision and a dramatic reduction in sample size. As a result, the timing of past climate, environment, and Earth system changes can be investigated at exceptional temporal precision. In this review, we summarize the principles and history of U–Th dating of speleothems. Finally, we highlight three studies that use U–Th dated speleothems to investigate past changes to the Asian monsoon, constrain the timing of sociopolitical change in ancient civilizations, and develop a speleothem-based calibration of the 14C timescale. 

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4. UID: The uranium isotope database

   https://doi.org/10.1016/j.chemgeo.2022.121221  

   Li, Haoyu; Tissot, François L.H. (February 2023, Chemical Geology)
5. Uranium Isotope Fractionation in Non‐sulfidic Anoxic Settings and the Global Uranium Isotope Mass Balance

   https://doi.org/10.1029/2020GB006649  

   Cole, Devon B.; Planavsky, Noah J.; Longley, Martha; Böning, Philipp; Wilkes, Daniel; Wang, Xiangli; Swanner, Elizabeth D.; Wittkop, Chad; Loydell, David K.; Busigny, Vincent; et al (August 2020, Global Biogeochemical Cycles)

   Abstract Uranium isotopes (²³⁸U/²³⁵U) have been used widely over the last decade as a global proxy for marine redox conditions. The largest isotopic fractionations in the system occur during U reduction, removal, and burial. Applying this basic framework, global U isotope mass balance models have been used to predict the extent of ocean floor anoxia during key intervals throughout Earth's history. However, there are currently minimal constraints on the isotopic fractionation that occurs during reduction and burial in anoxic and iron‐rich (ferruginous) aquatic systems, despite the consensus that ferruginous conditions are thought to have been widespread through the majority of our planet's history. Here we provide the first exploration of δ²³⁸U values in natural ferruginous settings. We measured δ²³⁸U in sediments from two modern ferruginous lakes (Brownie Lake and Lake Pavin), the water column of Brownie Lake, and sedimentary rocks from the Silurian‐Devonian boundary that were deposited under ferruginous conditions. Additionally, we provide new δ²³⁸U data from core top sediments from anoxic but nonsulfidic settings in the Peru Margin oxygen minimum zone. We find that δ²³⁸U values from sediments deposited in all of these localities are highly variable but on average are indistinguishable from adjacent oxic sediments. This forces a reevaluation of the global U isotope mass balance and how U isotope values are used to reconstruct the evolution of the marine redox landscape. 

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