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Abstract:The recyclable metal nanoparticle catalysts, rhodium in aluminum oxyhydroxide [Rh/ AlO(OH)] and iridium in aluminum oxyhydroxide [Ir/AlO(OH)], were simply prepared from readily available reagents. The catalysts showed high activities in the hydrogenation of various arenes and ketones under mild conditions. Selective hydrogenation was possible for bicyclic and tricyclic arenes in high yields. The catalysts were active at room temperature even with a hydrogen balloon. Also, the catalysts showed high turnover frequency (TOF) values under solventless conditions at 75 8C under 4 atm hydrogen pressure: ca. 1700 h À1 in the hydrogenation of benzene. Furthermore, Rh/AlO(OH) can be reused for at least 10 times without activity loss. The catalysts were characterized by the transmission electron microscopy (TEM), powder X-ray diffraction (XRD), inductively coupled plasma (ICP), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption and hydrogen chemisorption experiments. The sizes of rhodium and iridium particles were estimated to be 3-4 nm and 2-3 nm, respectively. Aluminum oxyhydroxide nanofibers of these catalysts have surface areas of 500-600 m 2 g À1 .

A new recyclable rhodium catalyst was synthesized by a simple procedure from readily available reagents, which showed high activities in the hydrogenation of various arenes under 1 atm H2 at room temperature.

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The purpose of this study is to select architectural design elements of super high-rise buildings to protect them from terrorism using explosives and to develop a vulnerability assessment model which can take into account the relative importance of each design element in anti-terrorism and the supplementary effects among them for achieving cost efficient architectural design.Four layers of defense and 27 architectural design elements were selected and the design elements were categorized into 7 supplementary groups based on their purpose and function. Then, design guidelines for each element were classified into 5 grades on the basis of its protection or risk level.Weights of each element were extracted through an AHP survey by anti-terrorism specialists. The results imply that the vulnerability of high-rise buildings to terrorism would be affected the most by the circumstances of the building and neighborhood, and the modification of heavily weighted design elements for separating unauthorized vehicles from a tower and blocking them outside of the site could be the most efficient design measures to counter terrorism.As a vulnerability assessment model, a bottom-up formula was suggested. To reflect the supplementary effects among design elements in the same group, an evaluation level integration methodology was included.