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In order to investigate the effect of cerium oxide addition, Cu-ZnO-CeO2 catalysts were prepared using co-precipitation method for water gas shift (WGS) reaction. A series of Cu-ZnO-CeO2 catalyst with fixed Cu Content (50 wt%, calculated as CuO) and a given ceria content (e.g., 0, 5, 10, 20, 30, 40 wt%, calculated as CeO2) were tested for catalytic activity at a GHSV of 95,541 h -1 , and a temperature range of 200 to 400 ℃. Cu-ZnO-CeO2 catalysts were characterized by using BET, SEM, XRD, H2-TPR, and XPS analysis. Varying composition of Cu-ZnO-CeO2 catlysts led the difference characteristics such as Cu dispersion, and binding energy. The optimum 10 wt% doping of cerium facilitated catalyst reduction at lower temperature and improved the catalyst performance greatly in terms of CO conversion. Cerium oxide added catalyst showed enhanced activities at higher temperature when it compared with the catalyst without cerium oxide. Consequently, ceria addition of optimal composition leads to enhanced catalytic activity which is attributed to enhanced Cu dispersion, lower binding energy, and hindered Cu metal agglomeration.

Purpose : Although eosinophilia is a common laboratory finding in many neonatal intensive care units (ICUs), its causative mechanisms remain obscure. We aimed to determine the causes of eosinophilia in the neonatal ICU environment. Methods : Serial eosinophil counts were determined weekly for 288 hospitalized, appropriately grown neonates. Infants were divided into four groups according to gestational age, and the incidence and etiologic factors of eosinophilia were retrospectively studied. Results : Absolute eosinophilia (>700/mm3) was documented in 18% (52/288) of neonates. Twenty-two infants (42.3%) exhibited mild eosinophilia (700-999 cells/mm3), 27 (51.9%) exhibited moderate eosinophilia (1,000–2,999 cells/mm3), and 3 (5.8%) exhibited severe eosinophilia (>3,000 cells/mm3). Of the 288 infants studied, 54 suffered sepsis. Thirty of these 54 infants (55.6%) showed eosinophilia, and 22 out of the remaining 234 infants (9%) without sepsis showed eosinophilia, indicating that eosinophilia was more prevalent in the sepsis group (P<0.05). All 5 infants suffering from bronchopulmonary dysplasia showed eosinophilia, and 47 out of the remaining 283 infants (16.7%) without bronchopulmonary dysplasia showed eosinophilia. Thus, eosinophilia was more prevalent in the bronchopulmonary dysplasia group (P<0.05). Furthermore, increased prevalence of eosinophilia was associated with respiratory distress syndrome, ventilator use, blood transfusion, and total parenteral nutrition (P<0.05). Conclusion : Our results suggest that eosinophilia is influenced by sepsis and bronchopulmonary dysplasia, although it can also occur idiopathically at birth. Moreover, the potential role of eosinophils in conditions such as wound healing and fibrosis in sepsis or chronic lung disease may be a cause of eosinophilia