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State College, LA, United States

Yao T.,Rensselaer Polytechnic Institute | Lu F.,Rensselaer Polytechnic Institute | Sun H.,Rensselaer Polytechnic Institute | Wang J.,Louisianan State University | And 2 more authors.
Journal of the American Ceramic Society | Year: 2014

Iodoapatite powder prepared by high-energy ball milling is densified by Spark Plasma Sintering to ∼96% theoretical density. X-ray Diffraction and First-principle Calculation indicates the sintered phase is iodine-deficient apatite with chemical composition of Pb9.85(VO4) 6I1.7 and iodine confinement over 8 wt%. Thermogravimetric analysis shows the bulk iodoapatite displays exceptionally stability without iodine release until 670°C. The greatly improved iodine confinement can be attributed to the dense matrix upon rapid consolidation from highly activated powders by mechanical attrition. © 2014 The American Ceramic Society.

Historically justified goals of the power theories development, general expectations and mathematical tools used for it are discussed in the paper. General features of the power theory of single-phase circuits with sinusoidal voltages and currents, the only commonly accepted power theory, were used as a reference for the presented discussion. Also discussed in this paper are the major issues of power theories development such as these: Should the power theory be formulated in the frequency or in time-domain? Should it be based on quantities averaged over a period or on instantaneous values? It was shown that in spite of the name "power" theory, the load currents rather than powers convey information on power properties of electrical circuits.

Czarnecki L.S.,Louisianan State University | Bhattarai P.,Louisianan State University
Przeglad Elektrotechniczny | Year: 2015

Energy flow related phenomena in three-phase unbalanced, linear, time-invariant (LTI) loads, supplied with asymmetrical, but sinusoidal voltage, in three-wire systems, are investigated in the paper. It is demonstrated that the load current can be decomposed into Currents’ Physical Components (CPC), associated with distinctive physical phenomena in the load. It is also shown how the CPC can be expressed in terms of the supply voltage and equivalent parameters of the load. An equivalent circuit of LTI loads at asymmetrical, but sinusoidal supply voltage is presented as well. This decomposition provides solid fundamentals for defining powers of such loads. © 2015 (publisher). All rights reserved.

Most of residential and industrial distribution systems as well as traction and distribution systems in commercial buildings are three-phase systems with a neutral conductor, denoted in this paper as 3pN systems. When loads are unbalanced then such systems cannot be now described as a whole in power terms because of a controversy regarding definition of the apparent, even if voltages and currents are sinusoidal. Consequently, it is not clear now how the apparent power and the power factor are affected by the load imbalance. The paper suggests definition of the apparent power for such systems and the power equation. It is based on the supply current decomposition into the Currents' Physical Components (CPC). The paper introduces two new powers that specify the effect of the load imbalance upon the apparent power of three-phase systems with a neutral conductor at sinusoidal voltages and currents.

Liao Z.,CAS Institute of Physics | Liao Z.,Louisianan State University | Gao P.,CAS Institute of Physics | Meng Y.,CAS Institute of Physics | And 4 more authors.
Applied Physics Letters | Year: 2011

We have investigated the electroforming (EF) and resistive switching (RS) of Al/Pr0.7Ca0.3MnO3 (PCMO)/Pt devices by using high-resolution transmission electron microscopy and x-ray photoelectron spectroscopy combined with transport measurement. The device prefers EF with positive bias with respect to Pt electrode and their endurance is enhanced with the chemically reactive Al electrode. The presence of an Al2O 3-δ layer in Al/PCMO junction indicates that the oxidization and reduction near the Al/PCMO interface play a key role in the RS. © 2011 American Institute of Physics.

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