Calorimeters for precision power dissipation measurements on controlled-temperature superconducting radiofrequency samples Rev. Sci. Instrum. 83, 124905 (2012) Implicit ligand theory: Rigorous binding free energies and thermodynamic expectations from molecular docking JCP: BioChem. Phys. 6, 09B608 (2012) Implicit ligand theory: Rigorous binding free energies and thermodynamic expectations from molecular docking J. Chem. Phys. 137, 104106 (2012) Differential membrane-based nanocalorimeter for high-resolution measurements of low-temperature specific heat Rev. Sci. Instrum. 83, 055107 (2012) Self consistently calibrated photopyroelectric calorimeter for the high resolution simultaneous absolute measurement of the specific heat and of the thermal conductivity AIP Advances 2, 012135 (2012) Additional information on Rev. Sci. Instrum. We present a scanning AC nanocalorimetry method that enables calorimetry measurements at heating and cooling rates that vary from isothermal to 2 × 10 3 K/s, thus bridging the gap between traditional scanning calorimetry of bulk materials and nanocalorimetry. The method relies on a micromachined nanocalorimetry sensor with a serpentine heating element that is sensitive enough to make measurements on thin-film samples and composition libraries. The ability to perform calorimetry over such a broad range of scanning rates makes it an ideal tool to characterize the kinetics of phase transformations or to explore the behavior of materials far from equilibrium. We demonstrate the technique by performing measurements on thin-film samples of Sn, In, and Bi with thicknesses ranging from 100 to 300 nm. The experimental heat capacities and melting temperatures agree well with literature values. The measured heat capacities are insensitive to the applied AC frequency, scan rate, and heat loss to the environment over a broad range of experimental parameters.

We demonstrate a route to synthesize ultra high-temperature ceramic coatings of ZrB 2 at temperatures below 1,300 K using Zr/B reactive multilayers. Highly textured crystalline ZrB 2 is formed at modest temperatures, because of the absence of any oxide at the interface between Zr and B, and the very short diffusion distance that is inherent to the multilayer geometry. The kinetics of the ZrB 2 formation reaction is analyzed using high-temperature scanning nano-calorimetry, and the microstructural evolution of the multilayer is revealed using transmission electron microscopy. We show that the Zr/B reaction proceeds in two stages: (1) inter-diffusion between the nano-crystalline Zr and the amorphous B layers, forming an amorphous Zr/B alloy; and (2) crystallization of the amorphous alloy to form ZrB 2 . Scanning nano-calorimetry measurements performed at heating rates ranging from 3,100 to 10,000 K/s allow determination of the kinetic parameters of the multilayer reaction, yielding activation energies of 0.47 eV and 2.4 eV for Zr/B inter-diffusion and ZrB 2 crystallization, respectively.

Micromachined nanocalorimetry sensors have shown excellent performance for high-temperature and high-scanning rate calorimetry measurements. Here, we combine scanning AC nanocalorimetry with in-situ x-ray diffraction (XRD) to facilitate interpretation of the calorimetry measurements. Time-resolved XRD during in-situ operation of nanocalorimetry sensors using intense, high-energy synchrotron radiation allows unprecedented characterization of thermal and structural material properties. We demonstrate this experiment with detailed characterization of the melting and solidification of elemental Bi, In, and Sn thin-film samples, using heating and cooling rates up to 300 K/s. Our experiments show that the solidification process is distinctly different for each of the three samples. The experiments are performed using a combinatorial device that contains an array of individually addressable nanocalorimetry sensors. Combined with XRD, this device creates a new platform for high-throughput mapping of the composition dependence of solid-state reactions and phase transformations. V C 2013 AIP Publishing LLC.

The reaction of Zr/B multilayers with a 50 nm modulation period has been studied using scanning AC nanocalorimetry at a heating rate of approximately 10 3 K/s. We describe a data reduction algorithm to determine the rate of heat released from the multilayer. Two different exothermic peaks are identified in the nanocalorimetry signal: a shallow peak at low temperature (200 -650°C) and a sharp peak at elevated temperature (650 -800°C). TEM observation shows that the first peak corresponds to heterogeneous inter-diffusion and amorphization of Zr and B, while the second peak is due to the crystallization of the amorphous Zr/B alloy to form ZrB 2 .

We combine the characterization techniques of scanning AC nanocalorimetry and x-ray diffraction to study phase transformations in complex materials system. Micromachined nanocalorimeters have excellent performance for high-temperature and high-scanning-rate calorimetry measurements. Timeresolved X-ray diffraction measurements during in-situ operation of these devices using synchrotron radiation provide unprecedented characterization of thermal and structural material properties. We apply this technique to a Fe 0.84 Ni 0.16 thin-film sample that exhibits a martensitic transformation with over 350 K hysteresis, using an average heating rate of 85 K/s and cooling rate of 275 K/s. The apparatus includes an array of nanocalorimeters in an architecture designed for combinatorial studies. Scanning calorimetry (SC) and x-ray scattering are powerful methods of materials characterization, the former quantifying thermal properties and the latter providing structural information. In a typical scanning calorimetry measurement, a phase transformation or solid-state reaction is efficiently explored through a temperature sweep, providing characterization of transformation or reaction temperature, latent heat, and the heat capacities of reactants and products.