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1. Solid‐State Investigation, Storage, and Separation of Pyrophoric PH ₃ and P ₂ H ₄ with α‐Mg Formate

   https://doi.org/10.1002/anie.202217534  

   Widera, Anna; Thöny, Debora; Aebli, Marcel; Oppenheim, Julius Jacob; Andrews, Justin L.; Eiler, Frederik; Wörle, Michael; Schönberg, Hartmut; Weferling, Norbert; Dincǎ, Mircea; et al (February 2023, Angewandte Chemie International Edition)

   Abstract Phosphane, PH₃—a highly pyrophoric and toxic gas—is frequently contaminated with H₂and P₂H₄, which makes its handling even more dangerous. The inexpensive metal–organic framework (MOF) magnesium formate, α‐[Mg(O₂CH)₂], can adsorb up to 10 wt % of PH₃. The PH₃‐loaded MOF, PH₃@α‐[Mg(O₂CH)₂], is a non‐pyrophoric, recoverable material that even allows brief handling in air, thereby minimizing the hazards associated with the handling and transport of phosphane. α‐[Mg(O₂CH)₂] further plays a critical role in purifying PH₃from H₂and P₂H₄: at 25 °C, H₂passes through the MOF channels without adsorption, whereas PH₃adsorbs readily and only slowly desorbs under a flow of inert gas (complete desorption time≈6 h). Diphosphane, P₂H₄, is strongly adsorbed and trapped within the MOF for at least 4 months. P₂H₄@α‐[Mg(O₂CH)₂] itself is not pyrophoric and is air‐ and light‐stable at room temperature. 

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2. Temperature dependence of irradiation-induced amorphization in a high-entropy titanate pyrochlore

   https://doi.org/10.1557/s43579-024-00648-y  

   Weber, William_J; Kinsler-Fedon, Candice; Keppens, Veerle; Zhang, Yanwen; Mir, Anamul_H (October 2024, MRS Communications)

   Abstract The temperature dependence of amorphization in a high-entropy pyrochlore, (Yb_0.2Tm_0.2Lu_0.2Ho_0.2Er_0.2)₂Ti₂O₇, under irradiation with 600 keV Xe ions has been studied using in situ transmission electron microscopy (TEM). The critical amorphization dose increases with temperature, and the critical temperature for amorphization is 800 K. At room temperature, the critical amorphization dose is larger than that previously determined for this pyrochlore under bulk-like 4 MeV Au ion irradiation but is similar to the critical doses determined in two other high-entropy titanate pyrochlores under 800 keV Kr ion irradiation using in situ TEM, which is consistent with reported behavior in simple rare-earth titanate pyrochlores. Graphical abstract 

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3. Resolving the contrasting leaf hydraulic adaptation of C₃ and C₄ grasses

   https://doi.org/10.1111/nph.20341  

   Baird, Alec_S; Taylor, Samuel_H; Pasquet‐Kok, Jessica; Vuong, Christine; Zhang, Yu; Watcharamongkol, Teera; Cochard, Hervé; Scoffoni, Christine; Edwards, Erika_J; Osborne, Colin_P; et al (January 2025, New Phytologist)

   Summary Grasses are exceptionally productive, yet their hydraulic adaptation is paradoxical. Among C₃grasses, a high photosynthetic rate (A_area) may depend on higher vein density (D_v) and hydraulic conductance (K_leaf). However, the higherD_vof C₄grasses suggests a hydraulic surplus, given their reduced need for highK_leafresulting from lower stomatal conductance (g_s).Combining hydraulic and photosynthetic physiological data for diverse common garden C₃and C₄species with data for 332 species from the published literature, and mechanistic modeling, we validated a framework for linkages of photosynthesis with hydraulic transport, anatomy, and adaptation to aridity.C₃and C₄grasses had similarK_leafin our common garden, but C₄grasses had higherK_leafthan C₃species in our meta‐analysis. Variation inK_leafdepended on outside‐xylem pathways. C₄grasses have highK_leaf : g_s, which modeling shows is essential to achieve their photosynthetic advantage.Across C₃grasses, higherA_areawas associated with higherK_leaf, and adaptation to aridity, whereas for C₄species, adaptation to aridity was associated with higherK_leaf : g_s. These associations are consistent with adaptation for stress avoidance.Hydraulic traits are a critical element of evolutionary and ecological success in C₃and C₄grasses and are crucial avenues for crop design and ecological forecasting. 

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4. Medium‐Entropy Engineering of Magnetism in Layered Antiferromagnet Cu _x Ni _{2(1‐ x )} Cr _x P ₂ S ₆

   https://doi.org/10.1002/adfm.202418722  

   Upreti, Dinesh; Basnet, Rabindra; Sharma, M_M; Chhetri, Santosh_Karki; Acharya, Gokul; Nabi, Md_Rafique_Un; Sakon, Josh; Benamara, Mourad; Mortazavi, Mansour; Hu, Jin (December 2024, Advanced Functional Materials)

   Abstract Antiferromagnetic van der Waals‐typeM₂P₂X₆compounds provide a versatile material platform for studying 2D magnetism and relevant phenomena. Establishing ferromagnetism in 2D materials is technologically valuable. Though magnetism is generally tunable via a chemical way, it is challenging to induce ferromagnetism with isovalent chalcogen and bimetallic substitutions inM₂P₂X₆. Here, we report co‐substitution of Cu¹⁺and Cr³⁺for Ni²⁺in Ni₂P₂S₆, creating Cu_xNi_2(1‐x)Cr_xP₂S₆medium‐entropy alloys spanning a full substitution range (x= 0 to 1). Such substitution strategy leads to a unique evolution in crystal structure and magnetic phases that are distinct from traditional isovalent bimetallic doping, with Cu and Cr co‐substitution enhancing ferromagnetic correlations and generating a weak ferromagnetic phase in intermediate compositions. This aliovalent substitution strategy offers a universal approach for tuning layered magnetism in antiferromagnetic systems, which along with the potential for light‐matter interaction and high‐temperature ferroelectricity, can enable multifunctional device applications. 

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5. A New Constraint on the Relative Disorder of Magnetic Fields between Neutral Interstellar Medium Phases

   https://doi.org/10.3847/1538-4357/ad5ade  

   Lei, Minjie; Clark, S_E (August 2024, The Astrophysical Journal)

   Abstract Utilizing Planck polarized dust emission maps at 353 GHz and large-area maps of the neutral hydrogen (Hi) cold neutral medium (CNM) fraction (f_CNM), we investigate the relationship between dust polarization fraction (p₃₅₃) andf_CNMin the diffuse high latitude ( $\left(b\right)>30°$) sky. We find that the correlation betweenp₃₅₃andf_CNMis qualitatively distinct from thep₃₅₃–Hicolumn density (N_Hi) relationship. At low column densities (N_Hi< 4 × 10²⁰cm⁻²) wherep₃₅₃andN_Hiare uncorrelated, there is a strong positivep₃₅₃–f_CNMcorrelation. We fit thep₃₅₃–f_CNMcorrelation with data-driven models to constrain the degree of magnetic field disorder between phases along the line of sight. We argue that an increased magnetic field disorder in the warm neutral medium (WNM) relative to the CNM best explains the positivep₃₅₃–f_CNMcorrelation in diffuse regions. Modeling the CNM-associated dust column as being maximally polarized, with a polarization fractionp_CNM∼ 0.2, we find that the best-fit mean polarization fraction in the WNM-associated dust column is 0.22p_CNM. The model further suggests that a significantf_CNM-correlated fraction of the non-CNM column (an additional 18.4% of the Himass on average) is also more magnetically ordered, and we speculate that the additional column is associated with the unstable medium. Our results constitute a new large-area constraint on the average relative disorder of magnetic fields between the neutral phases of the interstellar medium, and are consistent with the physical picture of a more magnetically aligned CNM column forming out of a disordered WNM. 

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