Despite the chemical and structural simplicity of MgB(2), at 39 K this compound has the highest known superconducting transition temperature (T(c)) of any binary compound. Electron doping by substituting Al for Mg leads to decreasing T(c), and the observed concentration dependent rate of decrease has been proposed to arise from the nonideal character of MgB(2)-AlB(2) solid solutions, which derives from the existence of an ordered Mg(0.5)Al(0.5)B(2) compound. Heterogeneous nanoscale structure patterns in solid solutions have emerged as an important concept for complex materials, ranging from actinide alloys and oxides to high-temperature cuprate superconductors and manganite-based materials exhibiting colossal magnetoresistivity. In this work we investigate the formation of structural heterogeneities in Mg(1-x)Al(x)B(2), which take the form of nanoscale Al-Al and Al-Mg domains of different geometries and sizes, using molecular statics and Monte Carlo simulations, and in particular we study the corresponding signatures in diffraction experiments. In order to undertake this task, we first derive appropriate Mg-Al-B semiempirical potentials within the modified embedded atom method formalism. These potentials are also applied to explore the equilibrium Mg(1-x)Al(x)B(2) phase diagram for 0 < x < 0.5. Additionally, density functional theory calculations were utilized to study the influence of heterogeneities on the electronic structure and charge distribution in Mg(1-x)Al(x)B(2).
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http://dx.doi.org/10.1021/jp902505r | DOI Listing |
Adv Sci (Weinh)
January 2025
Key (Guangdong-Hong Kong Joint) Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province, College of Chemical and Chemical Engineering, Shantou University, Shantou, 515041, P. R. China.
RuO-based materials are considered an important kind of electrocatalysts on oxygen evolution reaction and water electrolysis, but the reported discrepancies of activities exist among RuO electrocatalysts prepared via different processes. Herein, a highly efficient RuO catalysts via a facile hydrolysis-annealing approach is reported for water electrolysis. The RuO catalyst dealt with at 200 °C (RuO-200) performs the highest activities on both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in acid with overpotentials of 200 mV for OER and 66 mV for HER to reach a current density of 100 mA cm as well as stable operation for100 h.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Shaanxi Key Laboratory of Fiber Reinforced Light-Weight Composites, State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an, 710072, China.
Multicomponent Ti-containing ultra-high temperature ceramics (UHTCs) have emerged as more promising ablation-resistant materials than typical UHTCs for applications above 2000 °C. However, the underlying mechanism of Ti improving the ablation performance is still obscure. Here, (Hf,Zr,Ti)B coatings are fabricated by supersonic atmospheric plasma spraying, and the effects of Ti content on the ablation performance under an oxyacetylene flame are investigated.
View Article and Find Full Text PDFLangmuir
January 2025
Department of Chemistry, University of North Bengal, Raja Rammohanpur, Siliguri 734013, West Bengal, India.
Self-assembly of amino acids and short-peptide derivatives attracted significant curiosity worldwide due to their unique self-assembly process and wide variety of applications. Amino acid is considered one of the important synthons in supramolecular chemistry. Self-assembly processes and applications of unfunctionalized native amino acids have been less reported in the literature.
View Article and Find Full Text PDFJ Pharm Anal
December 2024
State Key Laboratory of Targeting Oncology, National Center for International Research of Bio-targeting Theranostics, Guangxi Key Laboratory of Bio-targeting Theranostics, Collaborative Innovation Center for Targeting Tumor Diagnosis and Therapy, Guangxi Medical University, Nanning, China.
Cartilage is solid connective tissue that recovers slowly from injury, and pain and dysfunction from cartilage damage affect many people. The treatment of cartilage injury is clinically challenging and there is no optimal solution, which is a hot research topic at present. With the rapid development of 3D printing technology in recent years, 3D bioprinting can better mimic the complex microstructure of cartilage tissue and thus enabling the anatomy and functional regeneration of damaged cartilage.
View Article and Find Full Text PDFJ Immunother Precis Oncol
February 2025
Department of Hematology and Medical Oncology, Emory University School of Medicine, Atlanta, GA, USA.
Introduction: Advanced penile squamous cell carcinoma (pSCC) is a rare and aggressive malignancy with a poor prognosis and an unmet need for biomarkers. We performed a retrospective evaluation of real-world efficacy, safety outcomes, and baseline inflammatory biomarkers in patients with advanced pSCC treated with immune checkpoint inhibitors (ICIs).
Methods: We performed a retrospective review of patients with advanced pSCC who received ICIs from 2012 to 2023 at the Winship Cancer Institute of Emory University in Atlanta, GA.
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