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A new scanning tunneling microscope reactor used for high-pressure and high-temperature catalysis studies Review of Scientific Instruments 79, 084101 (2008) To enable atomic-scale observations of model catalysts under conditions approaching those used by the chemical industry, we have developed a second generation, high-pressure, high-temperature scanning tunneling microscope (STM): the ReactorSTM. It consists of a compact STM scanner, of which the tip extends into a 0.5 ml reactor flow-cell, that is housed in a ultra-high vacuum (UHV) system. The STM can be operated from UHV to 6 bars and from room temperature up to 600 K. A gas mixing and analysis system optimized for fast response times allows us to directly correlate the surface structure observed by STM with reactivity measurements from a mass spectrometer. The in situ STM experiments can be combined with ex situ UHV sample preparation and analysis techniques, including ion bombardment, thin film deposition, low-energy electron diffraction and x-ray photoelectron spectroscopy.

In four lexical decision experiments we studied the effect of morphological complexity on word recognition. Some potentially relevant linguistic aspects of derived nouns were varied: the location of the affix (prefix vs. suffix); the genuineness of the affix (real vs. pseudo); the orthographic legality of pseudo-stems; semantic compositionality; the nature of the stem (free vs. bound); the origin of the complex word (Latinate vs. Germanic); the currency of the stem (current vs. moribund). Furthermore, in the first two experiments, we systematically varied the proportion of complex and simple words to see whether strategies influence morphological effects on recognition times. Consistent with Taft's notion of affix stripping, pseudoprefixed words show longer mean decision times and higher error rates than truly prefixed words. Further, the prefixed and nonprefixed (but not pseudoprefixed) words are processed equally rapidly, indicating that a decompositional process is efficient. No differences were found, however, for suffixed, pseudosuffixed, and nonsuffixed words. There was no effect of the proportion of simple and complex words. There are some indications that the etymological origin of words may affect recognition times, but no other linguistic aspects of derivations do so. The results of the four experiments are interpreted as supporting a left-to-right process for word recognition in which morphemes are extracted automatically. During this process information encoded by morphological structure becomes available for other processes.

An Atomic Force Microscope (AFM) has been integrated in a miniature high-pressure flow reactor for in-situ observations of heterogeneous catalytic reactions under conditions similar to those of industrial processes. The AFM can image model catalysts such as those consisting of metal nanoparticles on flat oxide supports in a gas atmosphere up to 6 bar and at a temperature up to 600 K, while the catalytic activity can be measured using mass spectrometry. The high-pressure reactor is placed inside an Ultrahigh Vacuum (UHV) system to supplement it with standard UHV sample preparation and characterization techniques. To demonstrate that this instrument successfully bridges both the pressure gap and the materials gap, images have been recorded of supported palladium nanoparticles catalyzing the oxidation of carbon monoxide under high-pressure, high-temperature conditions.