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The effects of the rare earth element La on the microstructure and mechanical properties of cast Al-5.4Cu-0.7Mg-0.6Ag alloys have been investigated through metallographic observation, scanning electron microscopy analysis, transmission electron microscopy, X-ray diffraction, and tensile testing. The present form and action mechanism of La have been analyzed. The findings indicate that the inclusion of trace amounts of La markedly diminishes the grain size in the Al-Cu-Mg-Ag alloy. Furthermore, as the La content increases, the alloy's strength is significantly improved. When the La concentration reaches 0.4 wt.%, the mechanical properties of the alloy, both at room temperature and at 350 °C, surpass those of the alloy lacking rare earth elements. When the added rare earth La content exceeds 0.2 wt.%, the emergence of the Al6Cu6La phase causes the alloy structure to exhibit a skeletal morphology, altering the morphology and distribution of excess second phases along grain boundaries, thereby impacting the alloy's overall performance. Incorporating La leads to a reduction in the size of the strengthening precipitate phase Ω while also enhancing its precipitation density, but an excess of La leads to the emergence of Al6Cu6La, depleting the available Cu and suppressing the precipitation of the Ω phase, ultimately affecting the mechanical properties of the alloy. [ABSTRACT FROM AUTHOR]

A series of lanthanide metal‐organic frameworks (MOFs) have been assembled with a series of functionalized [1,1′:4′,1′′‐terphenyl]‐4,4′′‐dicarboxylic acid ligands. The relationship between the ligand properties and the corresponding MOF properties has been studied. The structures of the MOFs depend on the solvent‐ligand and ligand‐ligand interactions, as well as the size of the non‐coordinating functional groups of the ligands. The differences in thermal stability among the ligands are inherited and amplified by corresponding lanthanide MOFs. The ligands bearing methyl, ether, and aldehyde functional groups are capable of sensitizing the emission from the lanthanide centers, whereas the ligand with α,β‐unsaturated ketone functional groups are non‐emissive due to the mismatch of the ligand and metal energy levels. [ABSTRACT FROM AUTHOR]

Trimethylamine-N-oxide (TMAO) is a biomarker of the cardiovascular disease that is one of the leading causes of worldwide death. Facile detection of TMAO can significantly improve the survival rate of this disease by allowing early prevention. However, the UV-vis silent nature of TMAO makes it intricated to be detected by conventional sensing materials or analytical instruments. Here we show a bilanthanide metal-organic framework functionalized by borono group for the recognition of TMAO. Superior sensitivity, selectivity and anti-interference ability were achieved by the inverse emission intensity changes of the two lanthanide centers. The limit of detection is 15.6 μM, covering the clinical urinary concentration range of TMAO. A smartphone application was developed based on the change in R-G-B chromaticity. The sensing mechanism via a well-matched outer-sphere interaction governing the sensing function was studied in detail, providing fundamentals in molecular level for the design of advanced sensing materials for UV-Vis silent molecules. Detection of trimethylamine N-oxide (TMAO) can allow for early intervention of cardiovascular disease, but is challenging to achieve using conventional materials and instruments owing to it being spectroscopically silent in the UV-visible region. Here, a series of bilanthanide metalorganic frameworks functionalised with a borono group are shown to detect TMAO with high sensitivity and selectivity by exploiting the inverse emission intensity changes of the two lanthanide centres. [ABSTRACT FROM AUTHOR]

Entacapone (ENT) is a powerful catechol‐O‐methyl transferase inhibitor that is used for the diagnosis and treatment of Parkinson's syndrome, but the amount used must be well controlled to avoid overtreatment and side effect. Fast and selective detection of ENT needs well‐matched energy levels and well‐designed sensor‐ENT interaction which is highly challenging. In this work, a water stable europium‐based metal‐organic framework (Eu‐TDA) was synthesized to detect ENT by luminescence with excellent reusability and selectivity in the presence of main coexisting and interference species of plasma with a limit of detection of 5.01 μM. The experimental results showed that the luminescence of Eu‐TDA can be effectively quenched by ENT via well‐designed photoinduced electron transfer mechanism and internal filtration effect mechanism in the system. [ABSTRACT FROM AUTHOR]