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The aim of this research was to examine the effect of copper cation-exchanged zeolites on the adsorption uptake of organic pollutants. Two beta zeolites with silica-to-alumina ratios of 25:1 and 150:1 were modified by copper cation exchange and their potential for the removal of phenol from aqueous solutions was investigated. It was found that copper loading could be increased by increasing the pH of the exchange to 7. The exchanged copper was found to be relatively resistant to leaching between 5 and 11. An increase in copper loading or silica content resulted in an increase in the adsorption capacity of the zeolite for phenol. Overall, it was found that the adsorption showed best fit to the generalized Langmuir-Freundlich isotherm model. The adsorption process was exothermic and yielded thermodynamic parameters that were contiguous with phenol adsorption. [ABSTRACT FROM AUTHOR]

The focus of the work described was the development of a solid catalytic adsorbent material capable of being regenerated, with the ability of adsorbing aniline from aqueous solution and the subsequent catalytic oxidation of the adsorbed aniline. Initially, an H-ZSM-5 zeolite was loaded with copper via an ion-exchange process to enhance its catalytic activity. Experimental results indicated an aniline adsorption level of ca. 37-42 mg/g for each of the unmodified H-ZSM-5, the 0.5 w/w% Cu-ZSM-5 or the 1.4 w/w% Cu-ZSM-5 zeolites. The Langmuir adsorption model was applicable to all aniline-on-zeolite adsorption processes, with the level of aniline adsorbed being largely unaffected by a change in temperature. The kinetics of the adsorption processes, indicated that the maximum uptake of aniline occurred within 50 min of contact. Assessment of the aqueous stability of the exchanged copper on the ZSM-5 zeolites indicated minimum copper leaching within the pH range 5-11, thus providing a stable working pH range for both the 0.5 w/w% and 1.4 w/w% Cu-ZSM-5 adsorbent materials. Catalytic oxidation studies on the adsorbed aniline indicated that the presence of copper in the zeolites significantly enhanced the degradation of aniline to predominantly carbon dioxide, water and nitrogen, with the production of significantly smaller levels of nitrogen oxide, benzene and nitrogen dioxide. [ABSTRACT FROM AUTHOR]

Submandibular duct relocation plus or minus excision of the sublingual glands are relatively simple procedures with low morbidity. Between 1981 and 2005, 71 submandibular duct relocation and 29 submandibular duct relocation plus excision of the sublingual glands procedures were conducted. Objectives: To compare both procedures including operative time, length of hospital stay, postoperative complications, drooling scores and parental satisfaction. Study design: Prospective study. Setting: Paediatric tertiary referral centre. Participants: Patients referred with excessive drooling after failure of conservative methods. Exclusion criteria: patients with recurrent aspiration pneumonias or dental caries. Two patients were lost to follow up and excluded from the study. Results: Operative time and length of hospital stay were increased in the submandibular duct relocation plus sublingual gland excision group. Drooling scores and parental satisfaction results were excellent, 93% of parents in the submandibular duct relocation group and 89% of parents in the duct relocation plus sublingual glands excision were satisfied and would recommend the procedure. There was no statistical difference ( P = 0.643) in drooling scores between the two procedures. Postoperative morbidity was higher with the addition of sublingual gland excision, with postoperative haemorrhage occurring in 13.7% and 36% of parents expressing concern over postoperative pain, compared with 3% postoperative haemorrhage rate with submandibular duct relocation and only 12% of parents expressing the same concerns. Conclusion: We conclude that both procedures are effective in drooling control, but the addition of sublingual gland excision increases morbidity and we are no longer excising these glands with submandibular duct relocation. [ABSTRACT FROM AUTHOR]

Juvenile angiofibroma is a rare, histologically benign tumor which occurs almost exclusively in adolescent boys. The morbidity and mortality associated with this tumor are related to its prominent vascularity and its propensity for aggressive local growth. From 1974 through 1988, 21 male patients with a diagnosis of juvenile angiofibroma were managed at the Toronto General Hospital or the Hospital for Sick Children, Toronto. Preoperative computed tomography was performed on 20 patients, selective angiography on 21 patients, and preoperative embolization on 15 patients. Primary surgery was performed on 67% of these patients, with radiation therapy used for advanced stage II and stage III disease or in response to patient preference. Pterygopalatine fossa involvement was demonstrated in 90% of the patients; as a result, the lateral rhinotomy approach was most commonly used in the surgical cases. A successful outcome was achieved in 86% of patients treated with surgery alone. Two patients underwent radiotherapy for salvage following postoperative recurrence. There were no treatment-related deaths and no major surgical complications. The value of computed tomography is discussed, the authors' treatment protocol is outlined, and the case series results are presented. [ABSTRACT FROM AUTHOR]