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In this study, sonochemically prepared (S) Pd catalysts supported on anatase (Ana) and rutile (Rut) were compared to incipient wetness impregnated (I) Pd catalysts for the direct synthesis of hydrogen peroxide. Pd/Ana-S and Pd/Rut-S achieved higher H2 conversion than Pd/Ana-I and Pd/Rut-I due to the improvement of metal dispersion by the sonochemical method. Especially, Pd dispersion on Pd/Rut-S was estimated to be six times higher than other catalysts, resulting in the highest H2O2 production rate. Through multiple characterizations (TEM, N2 adsorption-desorption, H2-TPR and CO-chemisorption), we discovered that many parts of the rutile crystals were cracked during the sonochemical treatment, obtaining rectangle shape rutile crystals and two times higher specific surface area. As a result, the sonochemical method played dual-functionalities as follows: physically cracking rutile crystals and inducing small Pd nucleation by cavitation. In addition, electron-deficient Pd species, beneficial for H2O2 selectivity, were dominantly observed on rutile by XPS analysis. This outcome was explained by unstable Ti3+ species on anatase favoring the electron-rich metal. Conclusively, it is demonstrated that the sonochemical method and rutile TiO2 have a substantial synergistic effect on both H2 conversion and H2O2 selectivity for the direct synthesis of hydrogen peroxide.

To find a non-invasive method of diagnosing hepatic fibrosis and cirrhosis, we evaluated the relationship of the hepatic cirrhosis grade between histopathology and mean grey level (MGL) in B-mode ultrasonography in CCl4-induced liver cirrhosis.Three groups of rats were treated with olive oil, CCl4, and CCl4 + silymarin. Rats were sacrificed at weeks 4, 8 and 12, after B-mode ultrasonography examination, and then analyzed histopathologically for fatty change and fibrosis.On the grade of fibrosis, the CCl4 group showed higher value at 8 and 12 weeks than the silymarin group. However, the fatty change was enhanced in the silymarin group, compared with the CCl4 group. The B-mode histogram values were the highest in the silymarin group, but the collagen rate was highest in the CCl4-treated group, at week 12. These results suggest that the B-mode histogram can be more affected by infiltration of lipid than by intact accumulation of collagen fibers.In the histogram of 8 and 12 weeks, there were significant differences between the CCl4-treated group and silymarin group in mean grey levels of B-mode ultrasonography. The histogram of B-mode mean grey level has a close correlation with fatty change and is useful for the diagnosis of liver fibrosis by histopathological analysis.

A 10-month old male Shi-tzu was presented with a week history of scurfy skin and whitish masses located in the ventral portion of tongue. Grossly, two whitish prominences with diameters of 3 to 4 mm were found on the underside of the tongue. Microscopically, in ulcerative epidermis, deposition of dense, amorphous granular basophilic calcium salts was separated by thin fibrous connective tissue containing mild inflammation. Many fascicles were characterized by replacement of degenerating myofibers with calcification. The precise cause of calcification could not be determined; however, it is interesting that two different lesions shown in calcinosis circumscripta and slight nutritional myopathy were also observed simultaneously only in the tongue.