ganic lanthanide complex films were prepared in situ via a sol-gel approach. The resulting hybrid films were transparent and crack-free. The films provided strong red or green emission when the lanthanide ion concentration reached 0.1 % (molar ratio to precursor TAT). Quenching and leaching effects were not observed in this system. Phase separation and lanthanide ion aggregation were controlled to nanometer dimensions. Further investigations on the morphology, luminescence behavior, and light emission devices of these hybrid organic±inorganic composite materials are in progress.

The acrylamide gelification process is a fast, inexpensive, reproducible, and easily scaled up chemical method for obtaining nanopowders of BaZrO3 that can be used for sintering crucibles and many electronic applications. This method enables the production of 100 g of high‐purity powders in one run, using simple laboratory equipment and low‐cost raw materials. The gelification process, synthesis temperature, and gas conditions required for obtaining high‐quality powders were the subjects of the present study. Fine powders were sintered to full density at 1450°C, making the fabrication of BaZrO3 crucibles possible for many laboratories.

Thanks to a novel technique (thermobaric analyser or TBA) for measuring the in situ pressure in quartz tubes, we have investigated the precursor quality for the synthesis of the superconductor Hg-1223 which is an essential parameter to control. We have made this study on the samples and we can conclude that this superconductor phase requires a ceramic precursor sintered in a low mixture gas flux. An excessively oxygenated precursor leads to overdoped superconducting phases, presence of other members with lower n, and some unreacted precursor. The precursor oxygenation degree also modifies the kinetics of formation of and the partial melting of the superconductor material may be affected.

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31.5 eV. Peaks were referenced to carbon at 285.0 eV to account for sample charging. Percentages for each carbon environment quoted within the text are derived from peak areas in the narrow scans.

In this paper we present a review of high-gas-pressure single crystal growth studies of YBa2Cu4O8 and Y2Ba4Cu7O15-x performed in oxygen pressure up to 3000 bar and Hg1-xMxBa2Can-1CunO2n+2+ (M = Pb, Re; n = 1-7) compounds in argon pressure up 11 000 bar at temperature up to 1200 °C. Chain compounds A1-xCuO2 (A = Sr, Ca, Ba) have been synthesized at high oxygen pressure up to 2000 bar. High-pressure phase diagram studies of the investigated systems are also discussed. Structure analyses of Y2Ba4CunO2n+x (n = 6-8), Hg1-xMxBa2Can-1CunO2n+2+ (M = Pb, Re; n = 1-8), Sr0.73CuO2 and (Sr,Ca)4Cu6O10 single crystals have been performed. The effects of substitutions and trends in bondlengths are discussed. The vortex state properties of HgBa2Ca2Cu3O8+ and YBa2Cu4O8 single crystals are compared. For Hg-based compounds, the influence of oxygen content, chemical substitutions and radiation defects on vortex pinning were determined. The quasi-one-dimensional cuprates Ca0.83CuO2 and Sr0.73CuO2 show an antiferromagnetically ordered state of long-range 3D character at T < 10 K. The spin dynamics of Sr0.73CuO2, measured by inelastic neutron scattering, indicate that this ordered state coexists with a dimerized singlet ground state.