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The experimentally observed reductive CO coupling in organouranium systems observed by Cloke and co-workers makes of interest the exploration of the structures and thermochemistry of simple Cp 2 U 2 (CO) n (n = 5, 4, 3, 2) derivatives. In this connection, the low-energy Cp 2 U 2 (CO) n (n = 2, 3, 4) structures contain two to four bridging η 2-µ-CO groups supplemented, in some cases, by one or two terminal CO groups. No examples of CO coupling to form C 2 O 2 ligands are found in any of these Cp 2 U 2 (CO) n structures in contrast to the previously studied Cp 2 Th 2 (CO) 4 system in which CO coupling to form C 2 O 2 ligands is observed. The retention of uranium valence electrons in low-energy Cp 2 U 2 (CO) n (n = 3, 4) structures, even after partial donation of uranium electrons to reduce Cp to Cpand CO to CO 2-, leads to a rich and complicated variety of U-U bonding modes as well as spin states from singlet to quintet. Of particular interest are uranium-uranium multiple bonds containing multiple single electron half-bond components in triplet and quintet spin state Cp 2 U 2 (CO) n structures. The formal uraniumuranium multiple bonds in such Cp 2 U 2 (CO) n structures exhibit some of the features of the quintuple bond of diuranium, U 2 , in which a typical σ + 2π triple bond similar to the C≡C triple bond of acetylene is supplemented by no less than four separate one-electron halfbonds. Thus the U≡U bonds in the lowest energy Cp 2 U 2 (CO) n (n = 2, 3) structures can be interpreted as formal triple bonds of various types with unusually short bond distances of ~2.5 Å and Wiberg bond indices of ~3.

Almost all proposed configurations and practical achievements based on superconductor/ferromagnet (S/F) heterostrucutres focus on s-wave superconductors. However, several attempts targeted also high temperature superconductors, most of them using manganite ferromagnets LaXMnO3 (X: Ca or Sr) and Y1Ba2Cu3O7−x (YBCO). Here we propose a new ferromagnetic material that can be used with YBCO for the fabrication of S/F hybrid structures. We show that a ferromagnetic order can be induced in a thin layer (∼130 nm thickness) of CaRuO3 grown by pulsed laser deposition on epitaxial YBCO film. Detailed magnetic and structural investigations show that the observations of the weak ferromagnetism are consistent with the magnetic order induced by in-plane tensile strain of about 1.7% and the easy-magnetization axis forms an angle of ∼180º with the layer plane. The value of the Curie temperature T Curie estimated using the Curie–Weiss law was 340 K. An unusual temperature dependence of the magnetic moment around the superconducting transition was observed in both field-cooled and zero-field-cooled configurations which is attributed to the paramagnetic Meissner effect.

The pro-apoptotic effect of new 2-thioxo-4-thiazolidinone derivative Les-3331 on MCF-7 and MDA-MB-231 cell lines ..

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