background: the possible role of cochlear function in tinnitus generation is still a matter of debate. to assess the role of outer hair cell dysfunction in tinnitus and its possible relationship with ultra-high frequency (uhf) hearing sensitivity, transient evoked otoacoustic emissions (teoae) and uhf hearing thresholds were investigated in normal hearing individuals with and without tinnitus. ...

A short history of interconnects in high and intermediate temperature solide oxide fuel cells form those based on ceramics to those made of metals.

Serials Li2O–Al2O3–SiO2 matrix glasses and glass-ceramics with different content of P2O5 were prepared by conventional melt cooling method and crystallization process. The effects of P2O5 content on microstructure and properties such as viscosity, melting temperature and coefficient of thermal expansion (CTE) of Li2O–Al2O3–SiO2–P2O5 glasses and glass-ceramics were investigated by DSC, XRD, CTE ...

Many energy conversion and storage devices exploit structured ceramics with large interfacial surface areas. Vertically aligned carbon nanotube (VACNT) arrays have emerged as possible scaffolds to support large surface area ceramic layers. However, obtaining conformal and uniform coatings of ceramics on structures with high aspect ratio morphologies is non-trivial, even with atomic layer deposi...

Structural steels with very high strength levels are often referred to as ultrahigh-strength steels (UHSS). The usage of UHSS has been extensively studied in aerospace industries and offshore platforms. In this study, medium carbon low alloy steel (AMS6305) was thermomechanicaly treated to obtain an ultra-high strength bainitic steel for aircraft engine compressor disk. A novel themomechanical ...

Transparent ceramics are important for scientific and industrial applications because of the superior optical and mechanical properties. It has been suggested that optical transparency and mechanical strength are substantially enhanced if transparent ceramics with nano-crystals are available. However, synthesis of the highly transparent nano-crystalline ceramics has been difficult using convent...

High temperature superconducting (SC) nanocomposites based on SC ceramics and various polymeric binders were prepared. Regardless of the size of the ceramics’ grains, the increase of their amount leads to an increase of resistance to rupture and modulus and a decrease in limiting deformation, whereas an increase in the average ceramic grain size worsens resistance properties. The SC, thermo-che...

Laminated Si/SiC ceramics were synthesized from porous preforms of biogenous carbon impregnated with Si slurry at a temperature of 1500 °C for 2 h. Due to the capillarity infiltration with Si, both intrinsic micro- and macrostructure in the carbon preform were retained within the final ceramics. The SEM micrographs indicate that the final material exhibits a distinguished laminar structure with...

Polycrystalline samples of Lead free (K0.5Na0.5)1−x(Li)x(Sb)x(Nb)1−xO3 ceramics with nominal compositions (x = 0.040 to 0.060) have been prepared by high temperature solid state reaction technique. X-ray diffraction (XRD) pattern shows that the crystal structure transforms from orthorhombic to tetragonal as Li and Sb content increases. Normal sintering process yield compounds with density ~98.2...

Based on precursor powders with a size of 200-300 nm prepared by the low-temperature solid-state reaction method, phase-pure YMnO₃ ceramics are fabricated using spark plasma sintering (SPS). X-ray diffraction (XRD) and scanning electron microscopy (SEM) reveal that the high-purity YMnO₃ ceramics can be prepared by SPS at 1000 °C for 5 minutes with annealing at 800 °C for 2 h. The relative densi...