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Abstract: The reduction of NO by CO+H2 in the presence of excess O2 has been studied on dispersed, low loading 0.5wt.% Pd-based catalysts. Two different methods of promotion were imposed separately and together, in order to investigate the feasibility of their synergy to enhance de-NO x efficiency of the catalytic system. Therefore, the Pd-catalysed NO+CO+H2 +O2 reaction was gradually studied over: (i) Pd/Al2O3–(TiO2) catalysts (support-mediated promotion by modifying the Al2O3 support with TiO2), (ii) K-dosed Pd(K)/Al2O3 catalysts (surface-induced promotion by modifying the Pd surface with the addition of K), and (iii) doubly-promoted Pd(K)/Al2O3–(TiO2) catalysts. Both (i) and (ii) methods of promotion were found to significantly promote the system, when acting individually. However, the de-NO x efficiency and N2-selectivity of the doubly-promoted Pd(K)/Al2O3–(TiO2) catalysts were found to be better than both of the other two cases, indicating a synergy during the simultaneous imposition of the two methods of promotion. The resulted benefits with the optimal doubly-promoted catalyst were very high, ∼85%, NO x conversion in a very wide temperature range (100–400°C), accompanied by very good N2-selectivities of ∼85%, i.e., 15–30 additional percentage units in comparison to the selectivity of the original un-promoted Pd/Al2O3 catalyst. [Copyright &y& Elsevier]

PURPOSE: Pseudomyxoma peritonei is a rare, chronic, relapsing, diagnostically challenging and poorly understood disease characterized by disseminated mucinous ascites and peritoneal implants. It is most commonly caused by an appendiceal primary cancer. We describe a case to emphasize the value of the cytologic evaluation of peritoneal fluid as a basic diagnostic test. MATERĠALS & METHODS: A 45-year-old male patient admitted to our hospital with abdominal and pelvic pain, bloating and digestive disorders. Two years earlier he had undergone surgery for an appendiceal tumor which histologically proved to be a low grade mucinous cystadenocarcinoma, so afterwards he received chemotherapy. A peritoneal washing was performed and the fluid was sent for cytologic evaluation. Smeras were prepared using the conventional and the liquid based methods abde were stain with Diff-Quick and Papanicolaou stains. RESULTS: The microscopic examination of the smears revealed the presence of extracellular mucin pools and relatively small rounded three-dimensioned clusters or irregular nuclear membranes, irregular chromatin distribution, variably sized nucleoli and occasionally mucinproducing features. Based on the above the diagnosis of pseudomyxoma peritonei was set. CONCLUSĠON: The cytomorphologic features and the patients‟ history are crucial factors for establishing a secure diagnosis of pseudomyxoma peritonei in peritoneal fluid which can lead to an accurate treatment. [ABSTRACT FROM AUTHOR]