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Multiwalled carbon nanotubes (CNTs) were functionalized with HNO 3 , HNO 3 /H 2 SO 4 , and HNO 3 /Na 2 CO 3 . The preparation of metal supported on mesoporous carbon nanotube catalyst is described. The catalysts were synthesized by impregnation of carbon nanotubes with different metallic precursors (H 2 PtCl 6 ‚6H 2 O, RuCl 3 ‚ H 2 O, and CuCl 2 ‚2H 2 O) followed by reduction. The structures of the CNT modified with HNO 3 , HNO 3 /H 2 -SO 4 , and HNO 3 /Na 2 CO 3 and CNT-supported metal catalysts have been characterized by means of Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and nitrogen adsorption/desorption isotherms (BET), and their activity was tested in continuous catalytic wet air oxidation of aniline. For the catalysts prepared with metal precursors, activities were found in the order of Pt/N-CNT > Cu/N-CNT > Ru/N-CNT. The structure of carbon nanotubes supported metal catalyst is responsible for the activity, and the absence of micropores enhances the potential capabilities of carbon nanotubes as support material.

The development of suitable intervention strategies to control Salmonella populations at the farm level requires reliable data on the occurrence and prevalence of the pathogen. Previous studies on Salmonella prevalence have focused on acquiring data from specific farm types and/or selected regions. The purpose of this study was to evaluate the distribution of this pathogen across a variety of farm types and regions in order to generate comparative data from a diverse group of environmental samples. Farm samples (n = 2,496) were collected quarterly from 18 different farms across five states (Tennessee, North Carolina, Alabama, California, and Washington) over a 24-month period. The participating farms included beef and dairy cattle operations, swine production and farrowing facilities, and poultry farms (both broiler chicken and turkey). The samples were analyzed for the presence of Salmonella by means of the U.S. Food and Drug Administration's Bacteriological Analytical Manual methods optimized for farm samples. Salmonella isolates were characterized by automated riboprinting. Salmonella serovars were recovered from 4.7% of all samples. The majority of positive findings were isolated from swine farms (57.3%). The occurrence of Salmonella was lower on dairy farms (17.9%), poultry farms (16.2%), and beef cattle farms (8.5%). The most commonly isolated serovar was Salmonella Anatum (48.4%), which was isolated notably more frequently than the next most common Salmonella serovars, Arizonae (12.1%) and Javiana (8.8%). The results of this study suggest that significant reservoirs of Salmonella populations still exist on swine production facilities and to a lesser extent in other animal production facilities. Data showed that the surrounding farm environment could be an important source of contamination.

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