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The pyrolysis of Ba(CF3COO)2·nH2O at temperatures up to 1000 °C, under flowing pure Ar, O2 and O2 saturated with water vapour, was extensively analysed. The existence of a:CF2 diradical is inferred and the formation of HF is observed directly for the first time during a trifluoroacetic acid salt decomposition. High resolution thermogravimetry, differential scanning calorimetry, X-ray diffractometry and scanning electron microscopy indicated that the exothermic two-stage decomposition of the anhydrate salt occurs between 282 and 325 °C, forming BaF2 via an unstable CF3COOBaF intermediate. Fourier transform infrared spectroscopy revealed the influence of water on the reactions of the liberated gaseous products, identifying CF3COOH, HF, CHF3 and CO2 as the principal volatile species, with C2F4, C2F6, CO and SiF4 also detected. The decomposition temperature is significantly lower than previously reported, which has implications for sol–gel processing.

A complete reaction path for the pyrolysis of trifluoroacetate-derived YBa2Cu3O7-! precursor solution is reported based on the authors’ investigations of the separate trifluoroacetate salt decompositions using thermal analysis and infrared spectroscopy of evolved gases. Optimal conditions for the pyrolysis of inkjet printed films are proposed, and the influence of pyrolysis on the YBa2Cu3O7-! crystal growth on a fully buffered Ni-5%W substrate is revealed. Optimisation of the annealing step revealed a strong dependence of the superconducting properties on the heat treatment temperature and duration. The critical temperature ( Tc ) and critical current density ( Jc ) of fully chemical solution deposited coated conductor samples were examined by means of inductive and Hall probe measurements.

The pyrolysis of Y(CF3COO)3·nH2O at temperatures up to 1,000 °C, under flowing pure Ar, O2 and O2 saturated with water vapour, was extensively analysed. The formation of HF is observed directly and the existence of a :CF2 diradical is inferred during a trifluoroacetic acid salt decomposition. High resolution thermogravimetry, differential scanning calorimetry, X-ray diffractometry and scanning electron microscopy indicated that the exothermic one-stage decomposition of the anhydrate salt occurs at 267 °C, forming YF3. Fourier transform infrared spectroscopy identified (CF3CO)2O, CF3COF, COF2, CO2 and CO as the principal volatile species; and revealed the influence of water on the reactions liberating gaseous CF3COOH, CHF3, HF, and SiF4 (from reactions with glass or quartz components). NO2 and N2O evolution suggested that traces of CH3NO2 were present in the starting material. Thermogravimetry and X-ray diffractometry indicated that the slow hydrolysis of the fluoride occurs between 630 and 655 °C, forming a mixture of Y2O3, YOF, Y7O6F9, and YF3. The decomposition and hydrolysis temperatures are significantly lower than previously reported, which has implications for sol–gel processing.

Functionalized arylcopper reagents have been produced in good yields at 25 degrees C from activated copper and the corresponding functionalized aryl iodides without the need of traditional organolithium or Grignard precursors. These organocopper compounds will undergo carboxylation with CO(2) to form the corresponding copper benzoates. In turn, these salts can be acidified to produce the functionalized aryl acids or treated with appropriate alkyl halides in the presence of a dipolar aprotic solvent to generate the corresponding aryl esters. This methodology permits the formation of functionalized organic acids and esters that could not be generated by the carboxylation of organomagnesium compounds.

Molecular methods tend to belong to the standard armamentarium of modern pathology. In some instances, these methods are able to identify nosological entities with better accuracy than conventional technique. These methods give useful complementary information to choose appropriate therapeutic strategy. C-erbB-2 overexpression in pancreatic cancer vary widely between 17 to 82%. C-erbB-2 gene is perspective target of anticancer therapies. 57 histologically confirmed tumors (51 pancreatic adenocarcinoma, 5 pancreatic neuroendocrine tumors and 1 carcinoma of Vater's ampullae) were analyzed for the presence of c-erbB-2 expression by immunohistochemistry. Correlation with time from initial symptoms until diagnosis, tumor size and TNM stage at diagnosis, tumor grade, type of operation and overall survival were investigated. C-erbB-2 overexpression was detected in 19.6% samples of pancreatic adenocarcinoma and in one case of Vater's ampullae carcinoma. C-erbB-2 overexpression was found in two of four insulinomas. Univariate statistical correlation stage between c-erbB-2 overexpression and time from initial symptoms until diagnosis, tumor size and TNM at diagnosis, tumor grade, type of operation and overall survival did not reach statistical significans in any parameter studied. C-erbB-2 oncogene was not found to be prognostic factor in pancreatic cancer. Its value to predict therapeutical response remains to be determined in prospective clinical trials.

Recent results on powder-in-tube in situ Cu-sheathed MgB2 wires have shown that copper powder additions to the core can accelerate the formation of MgB2, increasing its volume fraction and greatly decreasing the amount of Mg–Cu intermetallic phases present in the core after heat treatment. The amount of added copper and heat treatment conditions strongly affect the critical current of the wire and require optimization. To identify the optimum parameters, eight wires with starting core compositions of Mg+2B+xCu with x = 0, 0.01, 0.03, 0.05, 0.07, 0.09, 0.12 and 0.15 were prepared with two heating ramp rates and their properties were investigated by SEM, XRD and Jc and n-value measurements. The highest Jc was found to be for x = 0.09, whereas x = 0.03 resulted in the highest n-value. The results are relatively independent of the heating ramp rate used for heat treatment.