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The thermal behavior of ammonium molybdates, i.e. (NH 4 ) 6 Mo 7 O 24 •4H 2 O (1) and (NH 4 ) 2 MoO 4 (2), was studied in inert (N 2 ) and oxidizing (air) atmospheres by TG/DTA-MS, XRD, FTIR and SEM. The thermal decomposition sequence of 2 had similarities to 1; however, there were significant differences as well. When both of them were annealed, NH 3 and H 2 O were released parallel, and in air the asevolved NH 3 was burnt partially into NO and N 2 O. In both atmospheres, while 1 decomposed in four steps, the thermal decomposition of 2 involved 5 steps. In the case of 1, the intermediate products were Most decomposition steps were endothermic, except for the last step around 400 °C, where crystallization from the residual amorphous phase had an exothermic heat effect. In addition, the combustion of NH 3 also changed the DTA curve into exothermic in some cases. The morphology of the final products was characterized by 1-5 m sheet-like particles, except for annealing 2 in N 2 , when 0.5-1 m thick and 5-10 m long needle-shaped particles were detected.

In the literature data, several papers reported the synthesis by various chemical or physical methods of the SrCu 2 O 2 (SCO) having possible applications in thermoelectric or completely electronic devices such as solar cells, liquid crystal displays and touch screen. A great challenge is represented by the formation of the pure SrCu 2 O 2 (SCO), due to the high labiality of the Cu valence, depending on temperature. In the present paper, the thermal behavior of Sr-Cu-O gels obtained by sol-gel (SG) or microwave (MW)-assisted SG methods was studied in order to establish the appropriate thermal conditions for pure nanostructured SrCu 2 O 2 preparation. As reagents, copper and strontium acetylacetonate in alcoholic media were used. The starting solutions were homogenized either by stirring for 2 h at room temperature or were exposed to MW for 5 min at 300 W and a frequency of 2.45 GHz. Both solutions were left to gel at room temperature. The obtained gels were investigated by scanning electron microscopy, Fourier-transform infrared spectroscopy, as well as by thermal analysis combined with evolved gas analysis (TG/DTA-MS) measurements in air, inert and reducing atmospheres. For both type of samples, a stepwise thermal decomposition of the gels was noticed in a large temperature range. In the case of samples obtained by microwave-assisted SG method, a higher number of thermal effects were registered assigned to a higher number of molecular species formed in the sample. The residues obtained by non-isothermal treatment up to 900 °C, of both type of samples, were investigated by X-ray diffraction. The results demonstrate the influence of the MW on the SG synthesis and on the thermal properties of the resulted gels. Based on the obtained results, the required thermal treatment of the gels in order to obtain convenient precursors powders for obtaining pure SrCu 2 O 2 could be proposed.

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In the production of silver-enabled textiles, the amount of silver in the produced textile is always important. The goal of the present study is to develop a simple device that can directly detect silver instead of using destructive tests and calculations. The instrument developed by our group is simple, easy to use, and portable. It gives a voltage response corresponding to the silver content. To show its capabilities, a correlation is presented between the measured voltage and the relative amount of metal (i.e., silver) on silver-enabled textiles after several washing and electrolysis steps. The results of scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) measurements are also presented as a reference for the silver determinations.