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1. Temperature-dependent dielectric behavior of A 6 B 2O17 ( A  = Zr, Hf; B  = Nb, Ta) phases

   https://doi.org/10.1063/5.0219964  

   Spurling, R Jackson; Marakovits, Michael T; Hossain, Arafat; Almishal, Saeed_S I; Perini, Steven E; Lanagan, Michael T; Maria, Jon-Paul (August 2024, Applied Physics Letters)

   We report on temperature-dependent dielectric behavior of disordered ternary A6B2O17 (A = Zr, Hf; B = Nb, Ta)-form oxides in the GHz frequency range. The microwave dielectric properties including relative permittivity, dielectric loss, and temperature-dependent relative permittivity were characterized using cylindrical dielectric resonators using a resonant post measurement technique. Dielectric measurements through the resonant post method approach generally agree with dielectric measurements of A6B2O17 bulk ceramics measured through standard resonant post techniques. Coefficients describing the temperature-dependent relative permittivity for ternary A6B2O17 phases are strongly positive, suggesting contributions to polarizability arising from long-range mechanisms potentially associated with structural disorder. These observations support the working hypothesis that material functionality can be engineered by the chemical diversity and structural disorder possible in high configurational entropy A6B2O17 phases. 

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2. Modulus-based iterative methods for constrained ℓ _p – ℓ _q minimization

   https://doi.org/10.1088/1361-6420/ab9f86  

   Buccini, A; Pasha, M; Reichel, L (August 2020, Inverse Problems)
3. Rupture Directivity of the 2021 M _W 6.0 Yangbi, Yunnan Earthquake

   https://doi.org/10.1029/2022JB024321  

   Gong, Wenzheng; Ye, Lingling; Qiu, Yuxin; Lay, Thorne; Kanamori, Hiroo (September 2022, Journal of Geophysical Research: Solid Earth)

   Abstract The 2021M_W6.0 Yangbi, Yunnan strike‐slip earthquake occurred on an unmapped crustal fault near the Weixi‐Qiaoho‐Weishan Fault along the southeast margin of the Tibetan Plateau. Using near‐source broadband seismic data from ChinArray, we investigate the spatial and temporal rupture evolution of the mainshock using apparent moment‐rate functions (AMRFs) determined by the empirical Green's function (EGF) method. Assuming a 1D line source on the fault plane, the rupture propagated unilaterally southeastward (∼144°) over a rupture length of ∼8.0 km with an estimated rupture speed of 2.1 km/s to 2.4 km/s. A 2D coseismic slip distribution for an assumed maximum rupture propagation speed of 2.2 km/s indicates that the rupture propagated to the southeast ∼8.0 km along strike and ∼5.0 km downdip with a peak slip of ∼2.1 m before stopping near the largest foreshock, where three bifurcating subfaults intersect. Using the AMRFs, the radiated energy of the mainshock is estimated as ∼. The relatively low moment scaled radiated energyof 1.5 × 10⁻⁵and intense foreshock and aftershock activity might indicate reactivation of an immature fault. The earthquake sequence is mainly distributed along a northwest‐southeast trend, and aftershocks and foreshocks are distributed near the periphery of the mainshock large‐slip area, suggesting that the stress in the mainshock slip zone is significantly reduced to below the level for more than a few overlapping aftershock to occur. 

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4. Chondrus retortus (Gigartinales, Rhodophyta) in Hawai ‘ i: a taxonomic and biogeographic puzzle

   https://doi.org/10.1515/bot-2023-0019  

   Kittle, Ronald P; Veillet, Anne; Schmidt, William E; Fredericq, Suzanne; McDermid, Karla J (January 2024, Botanica Marina)

   Abstract Members of the genusChondrusare well-known from temperate and cold waters.Chondrus ocellatusHolmes was reported from Hawai‘i Island (19° N latitude) in 1999 as a new record based on vegetative and tetrasporangial characteristics. The first specimens were collected by Setchell in 1900 in Hilo, HI. The presence of aChondrusspecies in the subtropics has been a phycological enigma for over 100 years. We addressed the question of species identity and biogeographic affinities of the HawaiianChondruswith fresh cystocarpic material, DNA samples, and phylogenetic analyses. Analysis and comparison of five genes (nuclear: EF2; plastid:psbA,rbcL, and 23S/UPA; mitochondrial: COI) from HawaiianChondrusand holotype and topotype material of 10 of the 11 acceptedChondrusspecies indicate that Hawaiian specimens areC. retortusMatsumotoetShimada. However, unlike type material, the Hawaiian specimens are commonly pinnulate, vary significantly in secondary medullary filament density, and have mature cystocarps filling the entire medullary space. This study shows the value of using multi-gene loci and comparing multiple sequences of several species to confirm taxonomic conclusions. Our findings suggest thatC. retortusmay have immigrated via rafting on natural floating material or on ships’ hulls. Solving this old puzzle adds new insight into Hawaiian phytogeography. 

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5. Benchmarking the semi-stochastic CC( P ; Q ) approach for singlet–triplet gaps in biradicals

   https://doi.org/10.1063/5.0100165  

   Chakraborty, Arnab; Yuwono, Stephen H.; Deustua, J. Emiliano; Shen, Jun; Piecuch, Piotr (October 2022, The Journal of Chemical Physics)

   We recently proposed a semi-stochastic approach to converging high-level coupled-cluster (CC) energetics, such as those obtained in the CC calculations with singles, doubles, and triples (CCSDT), in which the deterministic CC(P;Q) framework is merged with the stochastic configuration interaction Quantum Monte Carlo propagations [J. E. Deustua, J. Shen, and P. Piecuch, Phys. Rev. Lett. 119, 223003 (2017)]. In this work, we investigate the ability of the semi-stochastic CC(P;Q) methodology to recover the CCSDT energies of the lowest singlet and triplet states and the corresponding singlet–triplet gaps of biradical systems using methylene, (HFH)−, cyclobutadiene, cyclopentadienyl cation, and trimethylenemethane as examples. 

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