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1. Benchmarking nitrous oxide adsorption and activation in metal–organic frameworks bearing coordinatively unsaturated metal centers

   https://doi.org/10.1039/D3TC04492K  

   Pitt, Tristan A.; Jia, Haojun; Azbell, Tyler J.; Zick, Mary E.; Nandy, Aditya; Kulik, Heather J.; Milner, Phillip J. (February 2024, Journal of Materials Chemistry C)

   Several MOFs are evaluated as adsorbents of anthropogenic N₂O emissions, the third most abundant greenhouse gas, through complimentary experimental and DFT analysis. N₂O activation in M₂(dobdc) MOFs is also studied. 

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2. Weak Interaction Physics at TwinSol

   https://doi.org/10.1051/epjconf/202125203001  

   Kolata’, J. J.; Brodeur, Maxime; Ahn, Tan; Bardayan, Dan; O’Malley, Patrick; Randhawa, J. S. (January 2021, EPJ Web of Conferences)

   Pakou, A.; Bonatsos, D.; Lalazissis, G.; Souliotis, G. (Ed.)

   A program to investigate the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) quark-mixing matrix by studying super-allowed mixed mirror β decays has been initiated at the TwinSol facility at Notre Dame. These mixed Fermi/Gamow-Teller (F-GT) decays, occurring between T=1/2 isospin doublets in mirror nuclei, provide a complimentary check on the data from super-allowed pure Fermi decays from 0 + to 0 + states. The first part of the program, involving the measurement of the lifetimes of the relevant nuclei to the required accuracy of one part in 10 3 or better, has nearly been completed. However, the additional complication introduced by F-GT mixing requires the use of an ion trap to measure the mixing ratio ρ with similar accuracy. The lifetime measurements, as well as progress in installing an ion trap at TwinSol , will be discussed. In addition, since the ion trap will require a dedicated beam line for its operation, an opportunity presented itself to greatly improve the performance of TwinSol for reaction studies with exotic nuclei. This took the form of an added dipole switching magnet coupled to a third solenoid to form the new TriSol facility currently under construction. The expected properties of TriSol , and its application to reaction studies of interest for nuclear astrophysics, will also be discussed. 

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3. Cobalt catalyzed multicomponent cyclizations of enynes and alkenes

   Herbort, James; RajanBabu, T. V. (April 2020, Book of Abstracts, 259th ACS National Meeting & Exposition, Philadelphia, PA)

   null (Ed.)

   Synthesis of complex organic molecules has relied heavily on the use of stoichiometric organometallic reagents. Strategies such as metal-catalyzed cycloisomerization bypass the need for these oftentimes harsh reagents and are valuable for constructing cyclic frameworks from simple unsaturated carbon sources. An important extension of this cyclization methodology is the incorporation of additional components accompanying the initial annulation. Through our studies we learned that cationic cobalt complexes can catalyze an intramolecular enyne cyclization, and subsequently form carbon-carbon bonds through intermolecular incorporation of feedstock alkenes into a presumed metallacycle intermediate. This strategy allows access to complex alicyclic and heterocyclic compounds from an earth abundant metal catalyst and readily available materials. Of note, is the complimentary reactivity and selectivity in this newly discovered cationic cobalt reaction manifold as compared to analogous rhodium and ruthenium catalysis. We discovered that product selectivity is dependent upon alkene identity, with activated alkenes and unactivated alkenes inserting into opposite sides of the cobaltacyclopentene intermediate. This remarkable selectivity provides access to two different motifs accompanying the cycle formed, either a linear diene or a styrene with a pendant functionalized acrylate. Over 25 different medicinally relevant pyrrolidines were accessed in this fashion and further elaborated on by post-synthetic modifications. In addition, the enantioselective variant of this reaction is also explored with selectivities up to 77% ee. 

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4. Flow Heterogeneity Controls Dissolution Dynamics in Topologically Complex Rocks

   https://doi.org/10.1029/2024GL114369  

   Kanavas, Z; Jimenez‐Martinez, J; Miele, F; Nimmo, J; Morales, V L (April 2025, Geophysical Research Letters)

   Abstract Rock dissolution is a common subsurface geochemical reaction affecting pore space properties, crucial for reservoir stimulation, carbon storage, and geothermal energy. Predictive models for dissolution remain limited due to incomplete understanding of the mechanisms involved. We examine the influence of flow, transport, and reaction regimes on mineral dissolution using 29 time‐resolved data from 3D rocks. We find that initial pore structure significantly influences the dissolution pattern, with reaction rates up to two orders of magnitude lower than batch conditions, given solute and fluid‐solid boundary constraints. Flow unevenness determines the location and rate of dissolution. We propose two models describing expected dissolution patterns and effective reaction rates based on dimensionless metrics for flow, transport, and reaction. Finally, we analyze feedback between evolving flow and pore structure to understand conditions that regulate/reinforce dissolution hotspots. Our findings underscore the major impact of flow arrangement on reaction‐front propagation and provide a foundation for controlling dissolution hotspots. 

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5. Reaction landscape of a mononuclear Mn ^III –hydroxo complex with hydrogen peroxide

   https://doi.org/10.1039/D3DT02672H  

   Grotemeyer, Elizabeth N; Parham, Joshua D; Jackson, Timothy A (October 2023, Dalton Transactions)

   The reaction of a mononuclear Mn^III–hydroxo complex with hydrogen peroxide under different reaction conditions yields bis(μ-oxo)dimanganese(iii,iv), Mn^III–hydroperoxo, and Mn^III–peroxo intermediates. 

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