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Single crystals of the quaternary R‐type ferrites BaLiRu5O11 [a = 11.628(6) Å, c = 13.7596(5) Å], and BaCu1+xRu5–xO11 [a = 11.6825(6) Å, c = 13.8051(7) Å], and their quinary solid solution BaLi1–xCux+δRu5–δO11 [a = 11.6453(2) Å, c = 13.7772(3) Å] were obtained by flux growth technique. X‐ray diffraction reveals the compounds to crystallize in space group P63/m with Z = 8. Measurements of the magnetic susceptibility of BaLiRu5O11 and BaCu1+xRu5–xO11, applying Curie–Weiss fits, confirm their paramagnetic behavior with temperature independent contributions of χ0,mol = 3.27 × 10–3 cm3·mol–1 and χ0,mol = 2.47 × 10–3 cm3·mol–1, respectively. Furthermore, the valence state of Ru in BaLiRu5O11 and BaCu1+xRu5–xO11 was determined to +3.8 by X‐ray absorption spectroscopy. Cu in BaCu1+xRu5–xO11 is dominating in a +2 state according to X‐ray photoelectron and X‐ray absorption spectroscopy, while a minor amount in +1 state may represent the excess copper substituting some Ru within a distorted Kagome net arrangement. [ABSTRACT FROM AUTHOR]

We present a combined experimental and theoretical Pb‐L3 X‐ray absorption near‐edge spectroscopy (XANES) to investigate the chemical state of Pb in transition metal perovskites PbTMO3 (TM = Ti, Ni). A pre‐edge feature originated from the excitation of a 2p core electron to the 6s orbital is only observed in PbNiO3, from which the valence of Pb is determined to be Pb4+ with two 6s holes. However, no such 2p–6s related excitation was observed in PbTiO3, indicating the formation of Pb2+ with fully occupied 6s2 state in this materials. Our results demonstrate that this pre‐edge peak from dipole allowed 2p–6s transition is a sensitive finger‐print of the Pb valence state in solid state materials. [ABSTRACT FROM AUTHOR]

Self-assembled vertical heterostructure with a high interface-to-volume ratio offers tremendous opportunities to realize intriguing properties and advanced modulation of functionalities. Here, a heterostructure composed of two visible-light photocatalysts, BiFeO3 (BFO) and ε-Fe2O3 ( ε-FO), is designed to investigate its photoelectrochemical performance. The structural characterization of the BFO-FO heterostructures confirms the phase separation with BFO nanopillars embedded in the ε-FO matrix. The investigation of band structure of the heterojunction suggests the assistance of photoexcited carrier separation, leading to an enhanced photoelectrochemical performance. The insights into the charge separation are further revealed by means of ultrafast dynamics and electrochemical impedance spectroscopies. This work shows a delicate design of the self-assembled vertical heteroepitaxy by taking advantage of the intimate contact between two phases that can lead to a tunable charge interaction, providing a new configuration for the optimization of photoelectrochemical cell. [ABSTRACT FROM AUTHOR]

Background and Aim The immune modulatory drug lenalidomide has shown promising anti-tumor activity in a clinical trial of patients with advanced hepatocellular carcinoma ( HCC). The present study explored whether lenalidomide can enhance the anti-tumor activity of sorafenib, the standard molecular targeted therapy for HCC. Methods The anti-tumor efficacy of single-agent or combination treatment was measured by change in tumor volume and animal survival using an orthotopic liver cancer model. Distribution of T-cell subpopulations in tumor-infiltrating lymphocytes ( TILs) and splenocytes derived from tumor-implanted mice was measured by flow cytometry. Depletion of relevant T-cell subpopulations or cytokines was done by co-administration of relevant antibodies with study drug treatment. Tumor cell apoptosis and tumor angiogenesis were measured by transferase deoxytidyl uridine end labeling assay and immunohistochemical study, respectively. Results Combination of sorafenib and lenalidomide produced significant synergistic anti-tumor efficacy in terms of tumor growth delay and animal survival. This synergistic effect was associated with a significant increase in interferon-γ expressing CD8+ lymphocytes in TILs and a significantly higher number of granzyme- or perforin-expressing CD8+ T cells, compared with vehicle- or single-agent treatment groups. Combination treatment significantly increased apoptotic tumor cells and vascular normalization in tumor tissue. The synergistic anti-tumor effect was abolished after CD8 depletion. Conclusions Lenalidomide can enhance the anti-tumor effects of sorafenib in HCC through its immune modulatory effects, and CD8+ TILs play an important role in the anti-tumor synergism. [ABSTRACT FROM AUTHOR]

Li-Ti Cation Mixing Enhanced Structural and Performance Stability of Li-Rich Layered Oxide The affiliation information for the National Synchrotron Radiation Research Center was presented incorrectly. The authors apologize for any inconvenience caused. [Extracted from the article]

Li‐rich layered metal oxides are one type of the most promising cathode materials in lithium‐ion batteries but suffer from severe voltage decay during cycling because of the continuous transition metal (TM) migration into the Li layers. A Li‐rich layered metal oxide Li1.2Ti0.26Ni0.18Co0.18Mn0.18O2 (LTR) is hereby designed, in which some of the Ti4+ cations are intrinsically present in the Li layers. The native Li–Ti cation mixing structure enhances the tolerance for structural distortion and inhibits the migration of the TM ions in the TMO2 slabs during (de)lithiation. Consequently, LTR exhibits a remarkable cycling stability of 97% capacity retention after 182 cycles, and the average discharge potential drops only 90 mV in 100 cycles. In‐depth studies by electron energy loss spectroscopy and aberration‐corrected scanning transmission electron microscopy demonstrate the Li–Ti mixing structure. The charge compensation mechanism is uncovered with X‐ray absorption spectroscopy and explained with the density function theory calculations. These results show the superiority of introducing transition metal ions into the Li layers in reinforcing the structural stability of the Li‐rich layered metal oxides. These findings shed light on a possible path to the development of Li‐rich materials with better potential retention and a longer lifespan. [ABSTRACT FROM AUTHOR]