[PDF] Top 20 Mat. Res. vol.2 número2

... Of the 44 papers presented at the Meeting, 17 were sub- mitted to MR for publication. In line with the editorial pol- icy of the magazine, all the articles were revised by at least 2 referees. Such careful ... See full document

... powder synthesis using the polymeric precursor method 3 . Figure 6 presents the FT-IR spectrum of the film heat- treated at different temperatures. At 325 °C, only vibrations related to the carboxyl group (COO - ) at ... See full document

... Unfortunately, one of the main problems observed for the present method was the lack of reproducibility, because some results are not obtained systematically. Basically, the morphology of the crystals could be different ... See full document

... EPR measurements have been performed in the tem- perature range of 20 K to 300 K. The results obtained for BTO and BTO:V samples, at 20 K, are shown in Fig. 3. At room temperature, the EPR spectra of the nominally pure ... See full document

... lites, It appears to be more or less observable depending upon the type of zeolite structure. It is a distinct band in the spectra of zeolites A, X, Y and Ω, but is less apparent in the spectra of zeolite P, ZK-5 among ... See full document

... The surface analysis using atomic force microscopy shows a 3D-like columnar growth for samples with ε = -0.75% and a planar growth for samples with ε = -0.5%, as shown in Figs. 6a and 6b, respectively. The planar surface ... See full document

... (99.5% pure) and from Aldrich Chemical Co. (99.999% pure). The repeated sublimation technique was employed due to the high vapor pressure of mercuric iodide (0.1 Torr at 120 °C). In this technique, the starting materials ... See full document

... Conducting polymers and their blends and composites have drawn the attention of several workers, both for their scientific importance in understanding the mechanisms re- sponsible for the elevated electrical conduction ... See full document

... (Table 2) and can be considered consistent with the value for stoichiometric ...0, 2, 3 and 7 appeared as aggregates of acicular primary particles under a scanning electron microscope, as can be seen in ... See full document

... The experimental setup used for the flash annealing treatments is shown in Fig. 2. An electrical current of constant intensity supplied by a current generator flows through the sample (a ribbon of length 0.08 - ... See full document

... Figures 1 and 2 present respectively the results of bulk density and specific surface area as a function of lead content for two pH ranges (variation about 0.5), while Figs. 3, 4, 5 and 6 show sorption-desorption ... See full document

... high cooling rates or melt undercooling inhibit the forma- tion of the pro-peritectic solid phase; the incompleteness of the peritectic reactions will cause the remaining liquid to progressively enrich in aluminium and ... See full document

... perature of 27 °C to 1.13 cm 3 /g for the temperature of 60 °C, presenting a maximum of 1.65 cm 3 /g for the gelation temperature of 40 °C. It can be seen by Table 4, a similar behavior of the specific surface area, ... See full document

... The oxidation of NiAl, NiAl-20at.%Fe and NiAl-30at.%Fe at 1000-1100 °C in air has been studied. Pure NiAl shows excellent oxidation resistance due to the formation of an Al 2 O 3 layer. NiAl-20Fe also shows good ... See full document

... To characterise strain distribution during the second path in tension, some of the tensile specimens were care- fully polished after prestraining. The specimens were elec- tropolished by immersion in a solution ... See full document

... showed that a great part of the Si atoms exist as silanol groups which originate resonance peaks at -110, -100 and -91 ppm. The presence of Al atoms may generate Si(3Si,Al) and Si(2Si, 2Al) environments which might be ... See full document

... impedance plots refer only to the conduction paths of zirconia because alumina conductivity is several orders of magnitude lower. Figure 4 shows the dependence of relaxation time on the zirconia concentration obtained ... See full document

... Granular magnetic solids (GMS) consisting of mag- netic nanosized particles embedded in an immiscible insu- lating or metallic matrix receive enormous attention nowadays due to new magnetic properties presented by these ... See full document

... As a consequence of the above evaluation, it was found that the powder mixture is the most suitable raw material for the production of sintered Ni-wicks. Mixture powder wicks presented a satisfactory capillary pumping ... See full document

... (see Table 1 - isomer shift (δ)). The octahedral distortion in the sample A2 is small (∆ (A1) < ∆ (A2)). There are two other components in the spectra, a doublet and a sextet in the interstitial site. The sextet of ... See full document