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Crystallographically texturing piezoelectric ceramics is a powerful method to bring the piezoelectric properties of polycrystalline ceramics closer to those of single crystals. Crystallographic orientation in piezoelectric ceramics is primarily achieved by tape casting and slip casting to align large, anisotropic template particles via shear stress in a randomly oriented piezoelectric matrix. For this research, the process of shear alignment in a model alumina tape casting system was explored to link common forming parameters, such as slurry viscosity, casting head aspect ratio, and casting rate to the magnitude and gradient of applied torque. Using Multiphysics modeling in COMSOL, it was determined that as slurry viscosity, casting head aspect ratio, and casting rate increased, so did the magnitude and gradient of torque during casting. As the magnitude and gradient of applied torque increased, the volume fraction of aligned particles and misalignment angle of the particles, as characterized by XRD rocking curves, increased by 14%, and decreased by 7° respectively. Dispersion characteristics of the piezoelectric system of interest, Pb(In1/2 Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT), and the acrylic binder system were characterized to develop a direct writing paste with appropriate rheology. Ceramic particle surface charge, characterized by zeta potential measurements, was adjusted via pH to maximize binding of the organic to the powder surface. Polymer conformation was also controlled with pH to produce an electrosterically stabilized dispersion. The rheology of the ceramic paste was characterized with oscillatory cone-and-plate rheometry and had an equilibrium storage modulus of 105 Pa, a yield stress of 520 Pa, and a recovery time of 7 seconds. Rheology was further tailored with the addition of 10 volume percent 20 -- 40 [mu]m wide barium titanate platelet particles, to serve as crystallographic templates for texturing, to produce a paste which filled space upon deposition but held the as-deposited shape and extruded at pressures manageable for the printing hardware. Additive manufacturing techniques offer access to crystallographic orientations and textured shapes that are not possible with tape and slip casting. To tailor the alignment of barium titanate particles during direct writing by altering the shear field, custom SLA nozzles with aspect ratios 2 -- 5 were designed and printed at Penn State. A series of samples were printed at rates from 5 mm/s to 20 mm/s with nozzles of aspect ratios 2 and 3. All printed ceramic samples were sintered to 98% density, measured by the Archimedes method, at 1050 °C for 10 h in flowing O2, which produced a fully textured microstructure. Increasing the aspect ratio from 2 to 3 and printing rate from 5 mm/s to 20 mm/s in turn increases the magnitude and gradient of torque generated during printing, as modeled with COMSOL. As torque is increased via printing rate the average angle of misalignment decreases by 10° and as torque is increased by increasing deposition nozzle aspect ratio from 2 to 3 the average angle of misalignment decreases by 6°. As misalignment angle in textured piezoelectric ceramics is decreased, the piezoelectric coefficient increases. In direct written PIN-PMN-PT decreasing the misalignment angle by ~5°, by increasing the printing nozzle aspect ratio from 2 to 3, increases the piezoelectric coefficient, as measured by strain-voltage loops, by 20%.

Here are tricks for creating cutting-edge interior design from tile original style setter at New York's trendsetting ABC Carpet & Home. The recent issue of Metropolitan Home magazine featured a New York apartment furnished with beautiful finds scavenged from flea markets. America has developed a yen for the vintage. Whether covering an entire wall with a salon-style arrangement of pictures creating the "attic" look; throwing together a grand canopied bed faked with gilded molding and draperies to evoke thc "exotic"; or choosing to go "spare" by displaying carefully selected objects, including old tools, glass boxes, or botanical prints, style setter Rebecca Purcell shows how anyone can create expressive rooms that make a statement. Full-color photographs in each chapter show how these fabulous styles were produced in different homes. Chapters include do-it-yourself projects for finishing touches, including tassels, aging fabrics and metals, valances and draperies, wall washing and stenciling, picture matting, and more.

Collection consists of the letters of Rebecca Timbres from 1936-1937 and Harry Timbres in 1936, she writing to family members, he primarily to his wife, but also to his daughters. Both their letters depict life in the Soviet Union in the mid-1930s and tell of their work; other letters, as from J. Barnard Walton explaining the creation of copies of Harry Timbres' letters; a 1974 biography of Harry Garland Timbres by Rebecca J. Timbres, included with the biography are copies of letters to Harry or Rebecca from such people as Rabindranath Tagore; poems by Harry G. Timbres. There are also 2 photographs of Harry Timbres.