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Four new 3d–4f heterobinuclear complexes [Zn(L)Sm(Py)(NO3)3] (1), [Zn(L)Eu(OAc)(NO3)2] (2), [Zn(L)Tb(Py)(NO3)3] (3) and [Zn(L)Dy(OAc)(NO3)2] (4); Py = pyridine; H2L = 6,6′-dimethoxy-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol) have been successfully prepared by the one-pot reaction of H2L with zinc(II) acetate, lanthanide(III) nitrate and a simple auxiliary ligand Py. Although the heterobinuclear complexes 1–4 are prepared in the same reaction condition, the auxiliary ligand Py doesn’t coordinate to the Zn(II) center of the complexes 2 and 4. Instead, the bridging µ-acetato ligand is present in the complexes 2 and 4. The coordination of the auxiliary ligand Py in the complexes 1 and 3 leads to the smaller distortion of square pyramidal coordination site of Zn(II), the higher coplanarity between the planes of ZnO(phenoxo)2 and LnO(phenoxo)2, and the longer Zn⋯Ln distance compared with the complexes 2 and 4. Moreover, the ligand (L)2− can selectively sensitize Sm(III) ion from among Sm(III), Eu(III), Tb(III) and Dy(III) ions, although these complexes would often exhibit f–f luminescence.

The submicron-sized Fe₃O₄ particles were synthesized by solvothermal method. Then polydopamine (PDA) was used to modify the surface of Fe₃O₄ particles. And then the core-shell Fe₃O₄@PDA@BSA (single layer and multilayer) microspheres were prepared by the layer by layer self-assembly method (SAM). In addition, Ag nanospheres were grafted onto the surface of Fe₃O₄@PDA particles to obtain Fe₃O₄@PDA-Ag core-shell nanoparticles using silver mirror reaction. The morphology and component of the obtained core-shell particles were characterized by transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The biocompatibility of the microspheres was researched

Two simple and sensitive kinetic-fluorometric methods have been developed for the determination of lanthanum(III): fluorescence quenching generated by the oxidation of safranine T or phenosafranine with potassium bromate in an acetate buffer solution. The rate of the oxidation reaction is significantly accelerated after adding lanthanum(III). A good linearity between the relative fluorescence intensity and lanthanum(III) is observed in the range of both 0.04 - 2.0 and 4.0 - 16 μg/mL. The detection limits have been 3.6 × 10-3 and 0.334 μg/mL respectively. The accuracy and reliability of the methods are further validated by recovery studies via a standard-addition method, with percentage recoveries ranging from 98 to 102%. Comparing the results of two measured reaction systems, we find that the safranine T reaction system provides high sensitivity and a wider linear range. In consequence, we have chosen the safranine T system to detect sample water, and explored the reaction mechanism.

Travelling Ionospheric Disturbances (TIDs) at Cusp latitude observed by EISCAT-Svalbard radar (ESR) were presented in this paper. Several representative cases were reported in detail, including a case of TIDs appearing at a broad altitude range (up to the topside of ionospheric F-region). Height profiles of wave number k were obtained in F-region using Maximum Entropy spectral Estimation (MESE) method when TIDs were monitored by various radar beams simultaneously. Simulation results indicated that TIDs observed at cusp latitude could be reasonable reproduced by carefully selecting AGW inputs.