Phase transition issues in the field of foods and drugs have significantly influenced these industries and consequently attracted the attention of scientists and engineers. The study of thermodynamic parameters such as the glass transition temperature (Tg), melting temperature (Tm), crystallization temperature (Tc), enthalpy (H), and heat capacity (Cp) may provide important information that can be used in the development of new products and improvement of those already in the market. The techniques most commonly employed for characterizing phase transitions are thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), thermomechanical analysis (TMA), and differential scanning calorimetry (DSC). Among these techniques, DSC is preferred because it allows the detection of transitions in a wide range of temperatures (−90 to 550 °C) and ease in the quantitative and qualitative analysis of the transitions. However, the standard DSC still presents some limitations that may reduce the accuracy and precision of measurements. The modulated differential scanning calorimetry (MDSC) has overcome some of these issues by employing sinusoidally modulated heating rates, which are used to determine the heat capacity. Another variant of the MDSC is the supercooling MDSC (SMDSC). SMDSC allows the detection of more complex thermal events such as solid–solid (Ts-s) transitions, liquid–liquid (Tl-l) transitions, and vitrification and devitrification temperatures (Tv and Tdv, respectively), which are typically found at the supercooling temperatures (Tco). The main advantage of MDSC relies on the accurate detection of complex transitions and the possibility of distinguishing reversible events (dependent on the heat capacity) from non-reversible events (dependent on kinetics).

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An efficient route to chemically functionalize reduced graphene oxide (rGO) with ruthenium organometallic compounds and the subsequent anchorage of Pt nanoparticles is reported. Two organometallic complexes, [(η6‐C6H5OCH2CH2OH) RuCl2]2 (Ru‐dim) and [(η6‐C6H4(CHMe2)Me)RuCl2]2 (Ru‐cym), as well as commercial RuCl3 ⋅ XH2O (Ru‐com) have been synthetized an used as functionalizing agents. By implementing a conventional polyol synthesis method, the Pt/rGORu‐dim, Pt/rGORu‐cym, Pt/rGORu‐com and Pt/rGO nanocatalysts have been synthetized. Characterization by XRD indicates that the presence of Ru leads to the formation of Pt−Ru alloyed phases due to overlapping of Pt fcc and Ru hcp reflections. When characterized for the methanol oxidation reaction (MOR) in acid media, Pt/rGORu‐dim reached a mass current density of 491.49 mA mgPt−1, higher than those generated by the other nanocatalysts. The results show that the functionalization of rGO with Ru‐dim remarkably increases the catalytic activity of Pt for the MOR, suggesting Pt−Ru metal−metal interactions that promotes the anodic reaction.

A novel growth technique, called atomic partial layer deposition (APLD), has been proposed to expand the applications of, and the research in, atomic layer deposition (ALD). This technique allows the possibility for the fabrication of well-controlled alloys on a single atomic layer scale. To demonstrate the capabilities of this technique, samples of HfO2 and TiO2 were prepared as conventional ALD nanolaminates through the repeated exposure of the separated metal-precursor and reactant. Subsequently, HfO2-TiO2 APLD growth mode samples were obtained by varying the precursor doses and exposure times to obtain a fractional coverage in the monolayer of Hf and Ti. The thickness and structure of the samples were studied by X-ray reflectivity. The surface topography was studied using atomic force microscopy along with Kelvin probe force microscopy for surface potential mapping. Clear differences on the surface, compared with the conventional HfO2/TiO2 ALD nanolaminates, were observed, which confirmed the HfO2-TiO2 APLD growth. The films were analyzed using X-ray photoelectron spectroscopy (XPS) depth profile scans and angle resolved XPS, where well-defined HfO2 and TiO2 contributions were found for both the conventional and APLD mode samples, and an additional contribution, assigned to a ternary phase Hf-Ti-O, in the APLD grown films was observed. This result confirms that Hf and Ti form an alloy in a monolayer by APLD mode growth.