In methane combustion, water tolerance of Pd-based catalysts is quite critical for stable performance, because produced in situ and a water-containing feed used under real conditions. Herein, water-tolerant mesoporous silica-alumina (H-MSA) was prepared by solvent deficient precipitation (SDP) using triethoxy(octyl)silane (TEOOS) aluminum isopropoxide (AIP). The H-MSA more tolerant to than ?-al...

The dispersion and coordination of aluminium species on the surface of silica-alumina based materials are essential for controlling their catalytic activity and selectivity. Al and Al are two common coordinations of Al species in the silica network and alumina phase, respectively. Al is rare in nature and was found hitherto only in the alumina phase or interfaces containing alumina, a behavior ...

BACKGROUND AND PURPOSE Excessive wear of acetabular liners in hip replacements may lead to osteolysis and cup loosening. Different head materials are currently used. We measured differences in wear between alumina and cobalt-chrome heads with the same polyethylene liner. PATIENTS AND METHODS 39 patients (43 hips) with osteoarthritis were included in a study with 10-year follow-up. Wear was me...

The principles of infrared emission spectroscopy are briefly reviewed with emphasis on the aspects of its application to the study of chemisorbed species. The ma in problems of sample preparation, selection of measurement conditions and the most suitable methods of data treatment are discussed. IR emittance spectra of two typical support materials for supported metal catalysts, aJumina and sili...

We previously reported the five-to-six-year results of the use of third-generation alumina-on-alumina bearings in a consecutive series of 100 primary cementless total hip arthroplasties. This report presents the longer-term outcomes of these same bearings, at a minimum of ten years postoperatively. Eighty-six of eighty-eight hips available for the study retained the original bearings at the tim...

This second paper in a series describes the relationship between grain growth kinetics and grain boundary complexions in silicadoped alumina. Dense high-purity silica-doped alumina samples were annealed for various times in the temperature range of 13001 and 19001C and their grain growth behavior was quantified. Four different grain boundary complexions were observed in silica-doped alumina, al...

In this paper, the influence of the atomic layer deposited alumina (Al2O3) thin films on the dynamics of a high-Q mechanical silicon oscillator was experimentally studied. The resonance frequency and Q value of uncoated oscillators used in this work were about f0 = 27 kHz and Q = 100 000 at p < 10−2 mbar and T = 300 K. Deposited alumina film thicknesses varied from 5 to 662 nm. It is demonstrat...

The concentration of alumina in the electrolyte is of great significance during the production of aluminum. The amount of the alumina concentration may lead to unbalanced material distribution and low production efficiency and affect the stability of the aluminum reduction cell and current efficiency. The existing methods cannot meet the needs for online measurement because industrial aluminum ...

Porous aluminum oxide membranes with a complete and even covering of alumina nanowires were formed in a one-step anodization process in dilute phosphoric acid electrolyte. The anodizing conditions can be adjusted to start forming alumina wires that originate on the surface of the porous alumina layer at the triple junction points (the edges of the hexagonal inter-pore structure where three pore...