Surface and interfacial engineering

The payoff to society from greater attention to the surface and interfacial engineering of concrete is potentially immense high-tech concretes that will prolong the life of public works and reduce their maintenance costs as well as dramatic new applications for this old reliable material. 

Surface and interfacial engineering. NSF should expand its support in this area, with emphasis on acquisition by chemical engineers of state-of-the-art instramentation for surface and interface studies. The need for such dedicated instrumentation can be met at a funding level of about 5 milhon per year. 

The National Science Formdation should expand its support to surface and interfacial engineering, focusing on surface chemistry, catalysis, electrochemistry, colloid and interfacial... 

The committee estimates that, in a given year, somewhere between 10 and 25 of the active groups in surface and interfacial engineering will need to acquire a major instrument for adaptation and use. A funding level of 5 million per year for major dedicated instrumentation can meet most of these needs. 

Many of the crucial problems for researchers in this area are the same as the ones encountered in other areas of surface and interfacial science. The research of chemical engineers on high-performance ceramic materials, field-induced bioseparations, and fouling also addresses phenomena such as agglomeration and clustering in dispersions and rheology of dispersions. For EPIDs,... 

A greater emphasis on surface and interfacial phenomena is needed for all chemical engineers interested in materials engineering. 

Particles can either be produced by bottom-up processes (e.g. precipitation) or top-down approaches (e.g. wet milling). In these processes particle-particle interactions become relevant when the particle size is below 1 pm. Engineering macroscopic product properties is then only possible through tailored surface and interfacial properties, no matter whether a bottom-up process like precipitation [11] or a top-down process such as milling in stirred media mills [12] is studied. Aggregation is an important aspect in both processes which are studied in the following. 

Industrial interest in nanomaterials derives from the novel properties they exhibit. These are defined for this entry as materials having engineered discrete particulate domains with diameters in the range of 1 nm to a few hundred nanometers. These domains may appear in many forms, such as dispersions of nanoparticles in a liquid, on surfaces, or embedded in a continuous matrix. The unique properties of nanomaterials are a consequence of the small size and extremely large interfacial areas. In this regime, dramatic variations in the chemical and physical properties of a material may be effected. Representative examples of size-critical properties, enabling new industrial applications, reviewed in this entry include surface and interfacial, catalytic, optical, and mechanical. 

The resulting models may be used in various applications, including chemical reaction equilibria, which is important to chemical reactor design, and phase equilibria, which arises in distillation, solvent extraction, and crystallization. But in addition to such traditional applications, thermodynamic models may also be used to help solve many other engineering problems, such as those involving surface and interfacial phenomena, supercritical extraction, hazardous waste removal, polymer and composite material development, and biological processing. 

Thomas Russell is Silvio O. Conte Distinguished Professor, Polymer Science and Engineering Department Director, Energy Frontier Research Center (EFRC), Polymer-Based Materials for Harvesting Solar Energy. His research interests are polymer-based nanoscopic structures, polymer-based nanoparticle assemblies, electrohydrodynamic instabilities in thin polymer films, surface and interfacial properties of polymers, polymer morphology kinetics of phase transitions, and supercritical fluid/polymer interactions. 

ToF-ERD is a powerful technique for profiling multilayered, multielemental samples, and thin films as may be found in the microelectronic industry, to provide information about the film stoichiometry, homogeneity, surface, and interfacial properties, necessary to engineer the film to the desired functional properties. 

John M. Vohs is the Carl V.S. Patterson Professor and chair of the Department of Chemical and Biomolecular Engineering at the University of Pennsylvania. He joined the faculty there after receiving a B.S. degree from the University of Illinois and a Ph.D. from the University of Delaware. Dr. Vohs research interest is in the field of surface and interfacial science, particularly the relationships between the local atomic structure of surfaces and their chemical reactivity. His work on structure-activity relationships for metal-oxide catalysts, especially those used for selective oxidation reactions and automotive emissions control systems, is widely known. In recent years, he has collaborated in the development of solid-oxide fuel cells that run on readily available hydrocarbon fuels, such as natural gas and diesel. Dr. Vohs has received numerous honors, including an NSF Presidential Young Investigator Award and two Union Carbide Research Innovation Awards, vohs seas.upenn.edu)... 

Kazuhiko Itagaki is with the USA Cold Regions Research and Engineering Laboratory, Hanover, NH, which he joined in 1964. He received his Ph.D. in Physics in 1960 from Hokkaido University, Sapporo, Japan. His interests are in surface and interfacial properties of single crystals and polycrystalline aggregates of ice and snow. 

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