We have studied the forces between a sphere and a plane surface of yttria‐partially‐stabilized tetragonal‐zirconia immersed in aqueous solutions of low‐molecular‐weight (Mw= 10 000) poly(acrylic acid) (PAA) using atomic force microscopy. The measurements are performed at high pH where the adsorbed, highly charged anionic polyelectrolyte extends far into the solution, resulting in a combination of polymeric (steric) and electrostatic interactions. Analysis of the experimental data using scaling theory shows that the polymeric contribution dominates and that the electrostatic contribution is small at relatively high ionic strength (0.01M NaCl). We find that the measured forces are highly dependent on time and interaction history of the absorbed PAA layer; consecutive compression‐decompression cycles result in an increase of the surface coverage and the range of the repulsive polymeric interaction. This buildup of PAA at the interface is strongly related to attractive bridging interactions manifested as strong adhesion during decompression at less than full surface coverage. The force results are compared to rheological observations of zirconia suspensions stabilized by the same dispersant; the poor colloidal stability and high viscosity at low surface coverage of PAA are related to the attractive bridging interactions.

Four different failure modes relevant to tubular supported membranes (thin dense films on a thick porous support) were analyzed. The failure modes were: 1) Structural collapse due to external pressure 2) burst of locally unsupported areas, 3) formation of surface cracks in the membrane due to TEC-mismatches, and finally 4) delamination between membrane and support due to expansion of the membrane on use. Design criteria to minimize risk of failure by the four different modes are discussed. The theoretical analysis of the two last failure modes is compared to failures observed on actual components.

The sections in this article are Emissions from Stationary Sources Drivers for Flue Gas Cleaning Technology The USA E urope A sia C hina J apan NO x Removal Technologies Nitrous Oxide (N 2 O) Selective Catalytic Reduction ( SCR ) SCR Technology SCR Catalysts Different Catalyst Types Choice of Carrier Optimization of Activity The Effect of Increasing V 2 O 5 Loading Activation Energy as a Function of Vanadium Content The Effect of Co‐Oxides SCR Reaction Mechanism for Vanadium Catalysts: the Eley–Rideal Route Global Kinetics The Importance of B rønsted Acidity The Influence of Reoxidation or NO 2 The Influence of Gas Composition on Reaction Rate The Influence of Water The Influence of O 2 Modeling Definition of Different Model Types Estimation of Interphase Mass Transfer Intraporous Mass Transfer Kinetic Expressions The Feasibility of Different Models Deactivation Chemical Poisoning Surface Fouling, Pore and Channel Clogging Sintering Catalyst Management and Regeneration SCR Catalyst Testing Laboratory‐ and Bench‐Scale Testing Pilot‐Scale Testing Slip‐Stream Reactors Full‐Scale Catalyst Testing Gas Sampling and Analysis Other Emissions Sulfur Removal The Wet Sulfuric Acid ( WSA ) Process and Combined WSA and De NO x ( SNOX ) Hydrogen Sulfide Carbon Monoxide Carbon Dioxide Hydrocarbons Dioxins Hg Oxidation and Capture Hg Oxidation Thermodynamics Hg Removal from Coal‐Fired Power Plants A Conventional Flue Gas Cleaning Processes B Sorbent Injection, Coal Additives, and Coal Blending Hg Oxidation Mechanism and Catalysis Alternative Processes Multipollutant Processes The DESONOX Process Other Combined Processes Catalytic Filters New Technologies Plasma‐Assisted Processes Photocatalytic Processes

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