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This book provides a welcome and very useful overview of the technologies which have breathed new life into a very long-established experimental stress analysis technique.

A method established in the present study has proven to be effective in the synthesis of Mn(2)O(3) nanocrystals by the thermolysis of manganese(III) acetyl acetonate ([CH(3)COCH=C(O)CH(3)](3)-Mn) and Mn(3)O(4) nanocrystals by the thermolysis of manganese(II) acetyl acetonate ([CH(3)COCH=C(O)-CH(3)](2)Mn) on a mesoporous silica, SBA-15. In particular, Mn(2)O(3) nanocrystals are the first to be reported to be synthesized on SBA-15. The structure, texture, and electronic properties of nanocomposites were studied using various characterization techniques such as N2 physisorption, X-ray diffraction (XRD), laser Raman spectroscopy (LRS), temperature-programmed reduction (TPR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The results of powder XRD at low angles show that the framework of SBA-15 remains unaffected after generation of the manganese oxide (MnO(x)) nanoparticles, whereas the pore volume and the surface area of SBA-15 dramatically decreased as indicated by N2 adsorption-desorption. TEM images reveal that the pores of SBA-15 are progressively blocked with MnO(x) nanoparticles. The formation of the hausmannite Mn(3)O(4) and bixbyite Mn(2)O(3) structures was clearly confirmed by XRD. The surface structures of MnO(x) were also determined by LRS, XPS, and TPR. The crystalline phases of MnO(x) were identified by LRS with corresponding out-of-plane bending and symmetric stretching vibrations of bridging oxygen species (M-O-M) of both MnO(x) nanoparticles and bulk MnO(x). We also observed the terminal Mn=O bonds corresponding to vibrations at 940 and 974 cm-1 for Mn(3)O(4)/SBA-15 and Mn(2)O(3)/SBA-15, respectively. These results show that the MnO(x) species to be highly dispersed inside the channels of SBA-15. The nanostructure of the particles was further identified by the TPR profiles. Furthermore, the chemical states of the surface manganese (Mn) determined by XPS agreed well with the findings of LRS and XRD. These results suggest that the method developed in the present study resulted in the production of MnO(x) nanoparticles on mesoporous silica SBA-15 by controlling the crystalline phases precisely. The thus-prepared nanocomposites of MnO(x) showed significant catalytic activity toward CO oxidation below 523 K. In particular, the MnO(x) prepared from manganese acetyl acetonate showed a higher catalytic reactivity than that prepared from Mn(NO(3))2.

Supported Pd, Au, and Pd−Au alloy catalysts are characterized with in situ diffuse reflectance infrared Fourier transform spectroscopy of CO adsorption (DRIFTS), quantitative powder X-ray diffraction, and X-ray photoelectron spectroscopy. The spectroscopic results presented in the paper demonstrate the existence of electron density transfer between Pd and Au atoms in alloy surfaces. In particular, the modification of the Pd electronic structure by the addition of Au is confirmed probably for the first time by the DRIFT spectra. The relationship between surface composition and catalyst performance in the synthesis of hydrogen peroxide directly from hydrogen and oxygen was established. Preliminary results indicate that the activity and selectivity of Pd−Au alloy catalysts can be significantly enhanced through adjusting the surface structures by changing the Au content in alloys.

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Phosphorus (P) modified H-ZSM-5 catalysts were prepared by wet impregnation method by varying P loadings from 0 to 7.43 wt % using phosphoric acid (H3PO4) as the P source. The catalysts were tested for ethanol dehydration in the temperature range of 523−723 K. The P-modified catalysts were found to be highly active and selective toward ethylene at 673 K and atmospheric pressure. In addition, the P-modified catalysts were found to be extremely stable more than 200 h without any sign of deactivation. However, the selectivity was found to be strongly dependent on several factors such as P content, reaction temperature, and space velocity (WHSV). The P-modified ZSM-5 catalysts were also found to be highly active for the dehydration of aqueous ethanol solutions (10 wt %) showing very high ethylene selectivity (above 98%) at significantly lower temperature 623 K. The catalysts were thoroughly characterized using various methods, including N2 physisorption, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric differential thermal analysis (TG-DTA), 1H, 27Al, and 31P magic angle spinning nuclear magnetic resonance (MAS NMR), and amonia temperature programmed desorption (NH3-TPD). 27Al MAS NMR spectra suggest that P addition facilitate the breaking of Si−O−Al bond that lead to a partial dealumination. NH3-TPD results indicate that total acidity as well as density of high strength acid sites were decreased with P loading.

A new heterogeneous Fenton-like system, consisting of supported Au catalysts and hydrogen peroxide, was proved to be effective in removing low level organic compounds (ca. 100 ppm) such as phenol, ethanol, formaldehyde, and acetone in aqueous solution. Among all gold catalysts the Au/ hydroxyapatite (Au/HAp) exhibits the highest activity, and even better than the conventional iron ions exchanged zeolite (Fe/ ZSM-5) catalyst. In particular, unlike the limited operational pH range (pH: 2 approximately 5) for the other heterogeneous Fenton catalysts such as Fe/ZSM-5, Au/HAp shows higher stability even in strong acid solution (pH approximately 2), due to almost no leaching of active metal from supports into solution. It can be potentially applied in treating the industrial wastewaters with strong acidity and purifying drinking water. In addition, in the case of complete oxidation of phenol, a plausible route was suggested for deep understanding of this process.

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