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This paper reviews the use of ceramic foams as structured catalyst supports. They are open-cell ceramic structures that may be fabricated in a variety of shapes from a wide range of materials, and they exhibit very high porosities with good interconnectivity. These characteristics result in a lower pressure drop than that observed with packed beds and high convection in the tortuous megapores, which, in turn, enhances mass and heat transfer. They are easily coated with high-surface-area catalytic components, using well-established techniques. Research in the past decade has produced a large amount of fundamental information that elucidates the desirable properties of ceramic foams. In addition, many applications involving important reactions have appeared in the open and patent literature, especially for catalytic processes that suffer certain limitations, such as those encountered in relieving high pressure drop with low-contact-time reactions at high space velocities or with narrow reactors in heat-transfer-limited systems and in controlling axial and radial temperature profiles in highly exothermic and endothermic reactions. These important contributions are discussed, and the advantages and shortcomings of using ceramic foams as structured catalyst supports to benefit commercial operations are considered.

Drawing on the responses provided by a survey of state court judges (N = 400), empirical evidence is presented with respect to judges’ opinions about the Daubert criteria, their utility as decision-making guidelines, the level to which judges understand their scientific meaning, and how they might apply them when evaluating the admissibility of expert evidence. Proportionate stratified random sampling was used to obtain a representative sample of state court judges. Part I of the survey was a structured telephone interview (response rate of 71%) and in Part II, respondents had an option of completing the survey by telephone or receiving a questionnaire in the mail (response rate of 81%). Survey results demonstrate that judges overwhelmingly support the “gatekeeping” role as defined by Daubert, irrespective of the admissibility standard followed in their state. However, many of the judges surveyed lacked the scientific literacy seemingly necessitated by Daubert. Judges had the most difficulty operationalizing falsifiability and error rate, with only 5% of the respondents demonstrating a clear understanding of falsifiability and only 4% demonstrating a clear understanding of error rate. Although there was little consensus about the relative importance of the guidelines, judges attributed more weight to general acceptance as an admissibility criterion. Although most judges agreed that a distinction could be made between “scientific” and “technical or otherwise specialized” knowledge, the ability to apply the Daubert guidelines appeared to have little bearing on whether specific types of expert evidence were designated as “science” or “nonscience.” Moreover, judges’ “bench philosophy of science” seemed to reflect the rhetoric, rather than the substance, of Daubert. Implications of these results for the evolving relationship between science and law and the ongoing debates about Frye, Daubert, Joiner, and Kumho are discussed.

It has been known for some time that particles of nickel oxide of less than about 100 nm in size show superparamagnetism that increases as the particle size decreases. The origin of the particle magnetic moment responsible for this behavior has never been fully explained. This research indicated that the size of the particle rather than the presence of nonstoichiometry or impurities of reduced nickel determines the moment. The critical experiment was the measurement of magnetization versus magnetic field for a sample of nickel oxide prepared under conditions that preclude metallic nickel. Almost identical results were found for the original sample, which was black in color and thus nonstoichiometric, and after mild reduction in hydrogen at 400 K, which produced stoichiometry and changed the color to green. The magnetic susceptibility was inversely proportional to the particle size for a given method of preparation. This is consistent with a simple model of incomplete edges on the bounding planes of the crystallite and provides a possible basis for a practical method for measuring particle size in nickel oxide-containing samples.

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