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Discusses thick film resistors as an alternative to thin-film platinum temperature sensors. Resistance and resistivity; Transmission electron microscopy characterization; Microscopic composition and crystallography; Role of morphology on temperature coefficient resistance.

Examines the effect of lattice stress relaxation on the microstructures of epitaxial thin films by domain structure studies of epitaxial SrRuO thin films grown on vicinal SrTiO substrates. Experimental procedures; Results and discussion; Conclusion.

The assessment of soil slope stability is an important task in geotechnical designs. This study uses finite element upper bound (UB) and lower bound (LB) limit analysis (LA) methods to investigate inhomogeneous soil slope stability on the basis of the conventional Mohr–Coulomb parameters. The obtained stability numbers are presented in inhomogeneous soil slope stability charts. In order to minimize manual reading errors when using the chart solutions, an artificial neural network (ANN) is employed to develop a stability assessment tool for the slopes investigated in this paper. The slope stability analysis using the ANN-based tool is convenient, and the predictions it provides are highly accurate. [ABSTRACT FROM AUTHOR]

Investigates the clustering of water on protonated molecular ions by vibrational predissociation spectroscopy. Resemblance of the hydroxide stretch spectra in the protonated ion-water clusters; Supersonic expansion of the ions to establish complexation with water.

Propane dispersion after the continuous leaking in the residential building is numerically simulated with FLUENT by computational fluid dynamic method. The variation characteristics of the concentration contribution and explosive range of propane are analyzed. The propane diffusion scope and explosive area increase with time. The highest concentration appears in the kitchen while the lowest concentration appears in the bedroom. Propane explosive area appears only in the kitchen and in the sunroom. Obvious stratification of the propane over the vertical height is due to gravity. The concentration, diffusion scope, and explosive area decrease with the number of windows open. The explosive range appears in the kitchen and the sunroom, but does not appear in the bedroom, the living room, or the bathroom. The research results can provide scientific support and references for risk evaluation, accident prevention and emergency rescue of propane hazards in the building. © 2015 American Institute of Chemical Engineers Environ Prog, 34: 973-981, 2015 [ABSTRACT FROM AUTHOR]

Barium titanate thin films deposited on MgO (0 0 1) by RF magnetron sputtering are composed of two new superstructures Ba4Ti5O10and Ba4Ti4O11formed as epitaxial nanodomain structures. Due to the nanometre scale size of domains and the complexity of the structure in the film, the single-crystal X-ray diffraction technique does not have the capability for the crystallographic structure determination of the two new superstructures. We used nanobeam electron diffraction to reconstruct the three-dimensional diffraction space and hence the symmetry of the new superstructures. Both Ba4Ti5O10and Ba4Ti4O11are monoclinic structures with a space group ofCm(b-unique axis). Ba4Ti5O10has a lattice parametera = 16.49 Å,b = 3.94 Å,c = 8.94 Å andβ = 103°, while Ba4Ti4O11hasa = 17.88 Å,b = 3.94 Å,c = 7.21 Å andβ = 98°. Atomic structural models for the two new superstructures were established by reconstructing the high-resolution transmission electron microscopy (HRTEM) images taken from the three major axes and refined by matching the simulated HRTEM images and calculated electron diffraction patterns with the experimental results. The two superstructures are epitaxially grown on MgO with theirb-axis parallel to the growth direction. [ABSTRACT FROM AUTHOR]

We report on the evolution of twin-coupled nanofinger structures in epitaxial Mn-doped Ba(Zr,Ti)O3 films on a (001) MgO substrate. XRD studies showed that the films are highly c-axis oriented epitaxial films. TEM and high-resolution TEM studies showed that Mn:BZT films present a pseudo-cubic perovskite structure composed of an epitaxial layer near the interface followed by the formation of twin-coupled nanofingers. The epitaxial grains and the twin-couple domains coexist by sharing their {111} or {110} plane as a common plane. The transition from the epilayer to nanofingers is accomplished by alternatively introducing {111} and {110} plane twin boundaries. This particular process results in gradual reduction of the lateral size of the epitaxial grains and eventually drives the epitaxial structure into twin-coupled nanofingers. The possible atomic structure models for the {110} plane twin boundary are discussed. [ABSTRACT FROM AUTHOR]

We report the twin-coupled multi-oriented domain structures in the epitaxial BZT20 (20%Zr) films grown on the (001) MgO substrate using pulsed-laser deposition. Transmission electron microscopy shows that the film consists of an epitaxial layer of pseudo-cubic perovskite structure and a nanopillar layer of multi-oriented twin domain structures near the surface. Four types of the twin domains were formed in the nanopillar layers by coherently joining their {111} with the epilayer and aligning their 〈110〉 directions parallel to the 〈110〉 axes of the epilayer. A non-uniform polarization switching behavior was observed due to the formation of such complex structure in the BZT20 films. [ABSTRACT FROM AUTHOR]

A model automotive exhaust catalyst, consisting of 2.25 wt% Pd supported on initially high-surface-area (88 m2/g) cerium–zirconium mixed oxide (Ce0.5Zr0.5O2), was studied by X-ray diffraction (XRD), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM), following high-temperature (1150°C) redox aging. Spherical Pd particles with size varying from 30 to 80 nm in diameter were found to be embedded both within single grains and at interfaces between multiple grains of the mixed oxide. X-ray energy-dispersive spectroscopy (EDS) and microbeam electron diffraction show that these particles are pure Pd, with face-centeredcubic structure. These results, together with elemental distribution maps obtained by EDS imaging, provide detailed visualization of an encapsulation phenomenon previously reported on the basis of XRD and TGA measurements alone. [ABSTRACT FROM AUTHOR]

Cluster isomers of H[sup +](CH[sub 3]OH)[sub 4]H[sub 2]O have been identified by vibrational predissociation spectroscopy in combination with mass-selected detection of photofragments. Ab initio calculations indicate that the cluster ion can exist in either CH[sub 3]OH[sub 2][sup +](CH[sub 3]OH)[sub 3]H[sub 2]O or H[sub 3]O[sup +](CH[sub 3]OH)[sub 4] isomeric forms. They can dissociate via a methanol loss or water loss channel, depending on the structure of the isomers. While water loss is the dominant channel of the dissociation, the methanol loss channel is readily accessible by the H[sub 3]O[sup +]-centered cluster isomer. We demonstrate in this study that mass-selected detection of photofragments produced by vibrational excitation is an effective way of identifying cluster isomers in the gas phase. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Behaviors of an excess proton in solute-containing water clusters were investigated using infrared spectroscopy and ab initio calculations. This investigation characterized the structures of protonated methanol-water clusters, H[sup +](CH[sub 3]OH)(H[sub 2]O)[sub n] with n=2-6, according to their nonhydrogen-bonded and hydrogen-bonded OH stretches in the frequency range of 2700-3900 cm-1. Ab initio calculations indicated that the excess proton in these clusters can be either localized at a site closer to methanol, forming a methyloxonium ion core (CH[sub 3]OH[sub 2][sup +]), or at a site closer to water, forming a hydronium ion core (H[sub 3]O[sup +]). Infrared spectroscopic measurements verified the calculations and provided compelling evidence for the coexistence of two distinct structural isomers, CH[sub 3]OH[sub 2][sup +](H[sub 2]O)[sub 3] and H[sub 3]O[sup +](CH[sub 3]OH)(H[sub 2]O)[sub 2], in a supersonic expansion. The spectral signatures of them (either CH[sub 3]OH[sub 2][sup +] or H[sub 3]O[sup +] centered) are the free-OH stretching absorption band at 3706 cm-1 of a single-acceptor-single-donor H[sub 2]O, and the band at 3673 cm-1 of a single-acceptor CH[sub 3]OH. At n=4-6, the clusters adopt structures similar to their pure water analogs with five-membered rings starting to form at n=5. The position of the excess proton in them varies sensitively with the number of solvent water molecules as well as the geometry of the clusters. To further elucidate the behaviors of the excess proton in these clusters, we analyze in detail the potential energy surface along the proton transfer coordinate for two specific isomers of n=2 and 4: MW2II and MW4I. It is found that the proton can be nearly equally shared by methanol and the water dimer subunit in the form of CH[sub 3]OH-H[sup +]-(H[sub 2]O)[sub 2], as substantiated by hydrogen bond cooperativity and zero-point vibrational effects. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A single source location method based on a independent doublet array is proposed. It is considered that the source is located at the far‐field of each doublet and the near‐field of the array. The presented method realises direction of arrival estimation by an ESPRIT‐like technique, and the range of the source by array geometry successively. It provides a simple and search‐free estimation method for single near‐field source location. Simulation results are presented that verify the effectiveness of the method. [ABSTRACT FROM AUTHOR]