Correlating metal poisoning with zeolite deactivation in an individual catalyst particle by chemical and phase-sensitive X-ray microscopy.

Fluid catalytic cracking (FCC) is the main conversion process used in oil refineries. An X-ray microscopy method is used to show that metal poisoning and related structural changes in the zeolite active material lead to a non-uniform core–shell deactivation of FCC catalyst particles. The study links the detrimental effect of V and Ni poisoning with zeolite destruction and dealumination in a spatial manner within a single FCC catalyst particle.

Indirect hemagglutination assay in patients with melioidosis in northern Australia.

Melioidosis is caused by the saprophytic organism Burkholderia pseudomallei. The use of the indirect hemagglutination assay (IHA) has found widespread use in areas endemic for this disease. Using this assay, we explored the serologic profile of 275 patients with culture-confirmed melioidosis in the Northern Territory of Australia.

Further evaluation of a rapid diagnostic test for melioidosis in an area of endemicity.

Immunochromatographic test (ICT) kits for the rapid detection of immunoglobulin G (IgG) and IgM antibodies to Burkholderia pseudomallei were compared to the indirect hemagglutination (IHA) assay. In 138 culture-confirmed melioidosis cases, sensitivities were 80, 77, and 88% for IHA, ICT IgG, and ICT IgM, respectively. In a prospective study of 160 consecutive sera samples sent for melioidosis serology, respective specificities were 91, 90, and 69, positive predictive values were 41, 32, and 18, and negative predictive values were 99, 98, and 100%.