The is a comprehensive review on the needs and potential storage technologies for electrical grid that is expected to integrate significant levels of renewables. This review offers details of the technologies, in terms of needs, status, challenges and future R&d directions.

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Electrochemical Energy Storage for Green Grid

There have been a number of review papers on layered silicate and carbon nanotube reinforced polymer nanocomposites, in which the fillers have high aspect ratios. Particulate–polymer nanocomposites containing fillers with small aspect ratios are also an important class of polymer composites. However, they have been apparently overlooked. Thus, in this paper, detailed discussions on the effects of particle size, particle/matrix interface adhesion and particle loading on the stiffness, strength and toughness of such particulate–polymer composites are reviewed. To develop high performance particulate composites, it is necessary to have some basic understanding of the stiffening, strengthening and toughening mechanisms of these composites. A critical evaluation of published experimental results in comparison with theoretical models is given.

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Effects of particle size, particle/matrix interface adhesion and particle loading on mechanical properties of particulate–polymer composites

https://zirconia.typepad.com/files/zirconia-as-a-ceramic-biomaterial---piconi---biomaterials-1999.pdf

Zirconia as a ceramic biomaterial

In this review the phenomenon of proton conductivity in materials and the elements of proton conduction mechanismsproton transfer, structural reorganization and diffusional motion of extended moietiesare discussed with special emphasis on proton chemistry. This is characterized by a strong proton localization within the valence electron density of electronegative species (e.g., oxygen, nitrogen) and self-localization effects due to solvent interactions which allows for significant proton diffusivities only when assisted by the dynamics of the proton environment in Grotthuss and vehicle type mechanisms. In systems with high proton density, proton/proton interactions lead to proton ordering below first-order phase transition rather than to coherent proton transfers along extended hydrogen-bond chains as is frequently suggested in textbooks of physical chemistry. There is no indication for significant proton tunneling in fast proton conduction phenomena for which almost barrierless proton transfer is suggest...

Proton Conductivity: Materials and Applications

http://fcbt.mse.gatech.edu/PDF/Bersra2007.pdf

A review on fundamentals and applications of electrophoretic deposition (EPD)

Linear calibration curves were developed for determining the content of free ZrO2 in partially stabilized zirconia ceramics by X-ray diffraction techniques. Two methods were studied. The matrix method, in which free ZrO2 was considered to be distributed in a matrix (the cubic phase), gave approximately equal mass absorption coefficients for the monoclinic and cubic phases. The polymorph technique, in which the cubic phase was considered to be a polymorph of ZrO2 and in which integrated intensities were used, gave the better results.

Phase Analysis in Zirconia Systems

The mechanisms of electrophoretic deposition (EPD) are discussed and their shortcomings identified. The kinetics of the processes involved are analyzed for constant-current and constant-voltage conditions. A method of determining the Hamaker constant of suspended particles is developed by modeling the relationship between the particle inter-action energy and the suspension stability. A three-probe dc technique is used to map the voltage profile around the depositing electrode, and the results are used to explain discrepancies between the calculated and experimentally observed voltage drops during deposition. A mechanism of deposition is proposed based on DLVO theory and particle double-layer distortion/thinning on application of a dc field to the suspension. Kinetic equations are developed for constant-current and constant-voltage EPD using mass balance conditions; these are verified by experiments. After the phenomenon is introduced and discussed, a critique of the application of EPD to the synthesis of ceramic shapes and coatings is given.

Electrophoretic Deposition (EPD): Mechanisms, Kinetics, and Application to Ceramics

The role of elastic, thermoelastic, and interfacial properties in the toughening of a brittle matrix by metallic second-phase particles was studied. Two composites were studied: glass+partly oxidized Ni particles (thermal expansion coefficient of the glasses lower than, equal to, and higher than that of Ni) and glass+partly oxidized Al particles (thermal expansion and elastic moduli equal). Weak interfacial bonding between the nickel and its oxide and developed stress concentrations are the major toughness limitations found in the glass/Ni composites. When the thermal expansion coefficient and elastic modulus of the second phase are sufficiently greater than that of the glass matrix, a propagating crack will bypass the particles. When the thermal and elastic stresses are minimized and satisfactory bonding is achieved (glass/Al composites), a 60x toughness increase was realized.

Toughening of Glasses by Metallic Particles

Partially stabilized zirconia (PSZ) ceramics in the system CaO-ZrO2 were characterized. The microstructure, as revealed by optical microscopy, consisted of grains of pure ZrO2 distributed in a matrix of fully stabilized material. Electron microscopy showed that the matrix grains have a complex substructure of 1000-A domains of cubic and monoclinic ZrO2. The grains appeared to fit Ubbelohde’s concept of a hybrid single crystal. Evidence obtained indicated that the substructure provides an effective stress-relieving mechanism during thermal shock. It is proposed that initiation of phase inversion in pure ZrO2 domains, even at subtransition temperatures (by thermal stresses), creates an extremely large microcrack density. On the basis of Hasselman’s thermal-shock criterion, only quasi-static crack propagation occurs during thermal shock of PSZ; evidence is presented to support this concept.

Structure and Thermomechanical Properties of Partially Stabilized Zirconia in the CaO-ZrO2 System

Explanations of the deposition process during electrophoretic deposition (EPD) are presented and their boundary conditions discussed. It is suggested increasing resistance during EPD is due to the deposit and not dilution of current carrying species in the suspension. Dialysis membrane experiments demonstrate ions carry significant current. Side-effects of two suspension-conditioning agents are described, i.e., TMAH and PEI. The former can induce “aging” in suspension as its surface adsorption varies with time and reduces suspension pH. PEI appears to adsorb on all ceramic and metal powders, so may be a universal EPD agent for stoichiometric deposition of ceramic/ceramic and ceramic/metal powder-mixtures. Novel structures produced by EPD are presented.

Patrick S. Nicholson

Papers

Phase Analysis in Zirconia Systems

Electrophoretic Deposition (EPD): Mechanisms, Kinetics, and Application to Ceramics

Toughening of Glasses by Metallic Particles

Structure and Thermomechanical Properties of Partially Stabilized Zirconia in the CaO-ZrO2 System

Electrophoretic deposition—mechanisms, myths and materials