A second oxidation state of the Mo3CuS4 cuboidal cluster has been prepared for the first time by reacting Cu+ or solid CuCl with the trinuclear MorV3 incomplete cuboidal cluster [Mo3S4(Hz0)9I4+ in aqueous acidic solutions and is here characterized as [ M O~C U S~( H~O )~O ]~+ . The previously prepared 4 f cube, which crystallizes from 4 M Hpts (pts-= p-toluenesulfonate) as the edge-linked double cube [{M03CuS4(H20)9}~](pts)8~20H~0, behaves as a single cube on elution from a cation-exchange resin with HCl or Hpts, and is assigned the corresponding [ M O~C U S~( H~O )~O ]~+ (or related) formula as the dominant species in solutions here studied. Furthermore EPR spectra for [Mo3CuS4(H20)1ol4+ in 2 M HCl or 2 M Hpts are similar and provide evidence for an unpaired electron interacting with a single Cu nucleus. An absorption peak in the near-IR at 975 nm for Hpts solutions only may be assigned to the presence of some double cube. At wavelengths in the UV-vis range, 2 M Hpts solutions obey Beer's law, and the expression for complexing with C1-gives K = 3.5 x lo3 M-' consistent with the presence of a single cube. At 25 "C kinetic studies on the addition of Cu+ to [Mo3S4(H20)9I4+ indicate a [Cu+]-dependent process rate constant of 980 M-' s-l at I = 2.00 M (LiC104). Kinetic studies are also reported for the 2: 1 hexaaquairon(II1) and [Co(dipic)2]-(dipic = pyridine-2,6-dicarboxylate) oxidations of [ M O~C U S~-(H20)1ol4+, which occur in two stages with intermediate formation of [Mo3CuS4(H2O)l5+. The second of the rate constants is reproduced in separate studies on [Mo~CuS4(HzO)lol5+. Studies on the [Ru(NH3)5(Hz0)l2+ reduction of [Mo3CuS4(H20)1ol5+ are also reported. As a result of this work an electron-transfer mechanism is proposed for reactions leading to the Cu2+ displacement of M2+ from [Mo3MS4(H20)1ol4+ cubes; e.g., M = Fe and Ni.

The martensitic 10CrMoVNb 91 (P91) steel has been developed for applications under high ultra supercritical pressure for steam power plants. The creep rupture strength of welded joints of this steel is limited by the fine grained region of its heat affected zone (HAZ). The microstructural changes occurring in this region during long term creep tests at 600uC and 70 MPa were examined using optical microscopy and scanning and transmission electron microscopy for comparison with the microstructure of this region after post-weld heat treatment. The factors which result in the reduction of creep rupture strength of the fine grained region of HAZ are discussed. It was found that the most effective factors reducing the creep rupture strength of the fine grained region of the HAZ of a welded joint in P91 steel, in comparison with the coarse grained region of the HAZ and the base metal of the welded joint, are the finer prior austenite grain size of the fine grained region, which accelerates the rate of growth of martensite lath subgrains and enhances creep cavitation, and also the lower peak temperature during welding, which results in a softer martensite matrix.Keywords: P91 weld joint, Long term creep at 600uC, Creep rupture strength, Microstructural instability, Fine grained region of HAZ, Prior austenite grain size Creep testCreep tests were performed on the base metal, the welded joint, and specimens simulating the fine grained HAZ region. Tests were carried out at 600uC, in air and at various constant applied loads by using single and

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Elderly patients with late onset depression had higher severity of depression as well as they were more cognitively affected regarding memory, verbal fluency, language, and visuospatial abilities. Vascular risk factors especially hypertension and diabetes mellitus were higher elderly patients with late onset depression and affects the severity of depression and degree of cognitive impairment.