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1. 2.2.2-Cryptand complexes of neptunium( iii ) and plutonium( iii )

   https://doi.org/10.1039/D1CC05904A  

   Goodwin, Conrad A.; Ciccone, Sierra R.; Bekoe, Samuel; Majumdar, Sourav; Scott, Brian L.; Ziller, Joseph W.; Gaunt, Andrew J.; Furche, Filipp; Evans, William J. (January 2022, Chemical Communications)

   New coordination environments are reported for Np( iii ) and Pu( iii ) based on pilot studies of U( iii ) in 2.2.2-cryptand (crypt). The U( iii )-in-crypt complex, [U(crypt)I 2 ][I], obtained from the reaction between UI 3 and crypt, is treated with Me 3 SiOTf (OTf = O 3 SCF 3 ) in benzene to form the [U(crypt)(OTf) 2 ][OTf] complex. Similarly, the isomorphous Np( iii ) and Pu( iii ) complexes were obtained similarly starting from [AnI 3 (THF) 4 ]. All three complexes (1-An; An = U, Np, Pu) contain an encapsulated actinide in a THF-soluble complex. Absorption spectroscopy and DFT calculations are consistent with 5f 3 U( iii ), 5f 4 Np( iii ), and 5f 5 Pu( iii ) electron configurations. 

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2. Modeling performance of rhamnolipid-coated engineered magnetite nanoparticles for U( vi ) sorption and separation

   https://doi.org/10.1039/d0en00416b  

   Sharma, Neha; Ghosh, Anushree; Fortner, John D.; Giammar, Daniel E. (July 2020, Environmental Science: Nano)

   Based on tunable properties, engineered nanoparticles (NPs) hold significant promise for water treatment technologies. Motivated by concerns regarding toxicity and non-biodegradability of some nanoparticles, we explored engineered magnetite (Fe 3 O 4 ) nanoparticles with a biocompatible coating. These were prepared with a coating of rhamnolipid, a biosurfactant primarily obtained from Pseudomonas aeruginosa . By optimizing synthesis and phase transfer conditions, particles were observed to be monodispersed and stable in water under environmentally relevant pH and ionic strength values. These materials were evaluated for U( vi ) removal from water at varying dissolved inorganic carbon and pH conditions. The rhamnolipid-coated iron oxide nanoparticles (IONPs) showed high sorption capacities at pH 6 and pH 8 in both carbonate-free systems and systems in equilibrium with atmospheric CO 2 . Equilibrium sorption behavior was interpreted using surface complexation modeling (SCM). Two models (diffuse double layer and non-electrostatic) were evaluated for their ability to account for U( vi ) binding to the carboxyl groups of the rhamnolipid coating as a function of the pH, total U( vi ) loading, and dissolved inorganic carbon concentration. The diffuse double layer model provided the best simulation of the adsorption data and was sensitive to U( vi ) loadings as it accounted for the change in the surface charge associated with U( vi ) adsorption. 

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3. DIMA: a depthwise CNN in-memory accelerator

   https://doi.org/10.1145/3240765.3240799  

   Angizi, Shaahin; He, Zhezhi; Fan, Deliang (November 2018, International Conference on Computer-Aided Design)

   In this work, we first propose a deep depthwise Convolutional Neural Network (CNN) structure, called Add-Net, which uses binarized depthwise separable convolution to replace conventional spatial-convolution. In Add-Net, the computationally expensive convolution operations (i.e. Multiplication and Accumulation) are converted into hardware-friendly Addition operations. We meticulously investigate and analyze the Add-Net's performance (i.e. accuracy, parameter size and computational cost) in object recognition application compared to traditional baseline CNN using the most popular large scale ImageNet dataset. Accordingly, we propose a Depthwise CNN In-Memory Accelerator (DIMA) based on SOT-MRAM computational sub-arrays to efficiently accelerate Add-Net within non-volatile MRAM. Our device-to-architecture co-simulation results show that, with almost the same inference accuracy to the baseline CNN on different data-sets, DIMA can obtain ~1.4× better energy-efficiency and 15.7× speedup compared to ASICs, and, ~1.6× better energy-efficiency and 5.6× speedup over the best processing-in-DRAM accelerators. 

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4. Synthesis and Characterization of Isostructural Th(IV) and U(IV) Pyridine Dipyrrolide Complexes

   https://doi.org/10.1021/acs.inorgchem.3c04391  

   Valerio, Leyla R; Hakey, Brett M; Leary, Dylan C; Stockdale, Erin; Brennessel, William W; Milsmann, Carsten; Matson, Ellen M (February 2024, Inorganic Chemistry)

   A series of pyridine dipyrrolide actinide(IV) complexes, (MesPDPPh)AnCl2(THF) and An(MesPDPPh)2 (An = U, Th, where (MesPDPPh) is the doubly deprotonated form of 2,6-bis(5-(2,4,6-trimethylphenyl)-3-phenyl-1H-pyrrol-2-yl)pyridine), have been prepared. Characterization of all four complexes has been performed through a combination of solid- and solution-state methods, including elemental analysis, single crystal X-ray diffraction, and electronic absorption and nuclear magnetic resonance spectroscopies. Collectively, these data confirm the formation of the mono- and bis-ligated species. Time-dependent density functional theory has been performed on all four An(IV) complexes, providing insight into the nature of electronic transitions that are observed in the electronic absorption spectra of these compounds. Room temperature, solution-state luminescence of the actinide complexes is presented. Both Th(IV) derivatives exhibit strong photoluminescence; in contrast, theU(IV) species are nonemissive. 

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5. Leveraging a reduced polyoxomolybdate-alkoxide cluster for the formation of a stable U( v ) sandwich complex

   https://doi.org/10.1039/D4SC02644F  

   Shiels, Dominic; Brennessel, William W; Crawley, Matthew R; Matson, Ellen M (July 2024, Chemical Science)

   Actinide doping enhances redox chemistry of polyoxomolybdate-alkoxide clusters; the first isolable U(v) polyoxometalate cluster is reported. 

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