Degradation of azo-dye Orange II by a photoassisted Fenton reaction using a novel composite of iron oxide and silicate nanoparticles as a catalyst

A novel nanocomposite of iron oxide and silicate, prepared through a reaction between a solution of iron salt and a dispersion of Laponite clay, was used as a catalyst for the photoassisted Fenton degradation of azo-dye Orange II. This catalyst is much cheaper than the Nafion-based catalysts, and our results illustrate that it can significantly accelerate the degradation of Orange II under the irradiation of UV light (lambda = 254 nm). An advantage of the catalyst is its long-term stability that was confirmed through using the catalyst for multiple runs in the degradation of Orange II. The effects of the H2O2 molar concentration, solution pH, wavelength and power of the LTV light, catalyst loading, and initial Orange II concentration on the degradation of Orange 11 were studied in detail. In addition, it was also found that discoloration of Orange 11 undergoes a faster kinetics than mineralization of Orange II and 75% total organic carbons of 0.1 mM Orange II can be eliminated after 90 min in the presence of 1.0 g of Fe-nanocomposite/L, 4.8 mM H2O2, and 1 x 8W UVC.

Cardiovascular risk estimation by professionally active cardiovascular nurses: Results from the Basel 2005 Nurses Cohort

Background Nurses play a key role in the prevention of cardiovascular disease (CVD) and one would, therefore, expect them to have a heightened awareness of the need for systematic screening and their own CVD risk profile. The aim of this study was to examine personal awareness of CVD risk among a cohort of cardiovascular nurses attending a European conference. Methods Of the 340 delegates attending the 5th annual Spring Meeting on Cardiovascular Nursing (Basel, Switzerland, 2005), 287 (83%) completed a self-report questionnaire to assess their own risk factors for CVD. Delegates were also asked to give an estimation of their absolute total risk of experiencing a fatal CVD event in the next 10 years. Level of agreement between self-reported CVD risk estimation and their actual risk according to the SCORE risk assessment system was compared by calculating weighted Kappa (κw). Results Overall, 109 responders (38%) self-reported having either pre-existing CVD (only 2%), one or more markedly raised CVD risk factors, a high total risk of fatal CVD (≥ 5% in 10 years) or a strong family history of CVD. About half of this cohort (53%) did not know their own total cholesterol level. Less than half (45%) reported having a 10-year risk of fatal CVD of < 1%, while 13% reported having a risk ≥ 5%. Based on the SCORE risk function, the estimated 10-year risk of a fatal CVD event was < 1% for 96% of responders: only 2% had a ≥ 5% risk of such an event. Overall, less than half (46%) of this cohort's self-reported CVD risk corresponded with that calculated using the SCORE risk function (κw = 0.27). Conclusion Most cardiovascular nurses attending a European conference in 2005 poorly understood their own CVD risk profile, and the agreement between their self-reported 10-year risk of a fatal CVD and their CVD risk using SCORE was only fair. Given the specialist nature of this conference, our findings clearly demonstrate a need to improve overall nursing awareness of the role and importance of systematic CVD risk assessment.

Zr-Laponite pillared clay-based nickel catalysts for methane reforming with carbon dioxide

Zr-Laponite pillared clays were prepared and used as supports of nickel catalysts for the methane reforming reaction with carbon dioxide to synthesis gas. The structural and textural characteristics of supports and catalysts were systematically examined by N-2 adsorption/desorption and X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron spectroscopy (TEM) techniques. The catalytic performance and carbon deposition were investigated. It is found that Zr-Laponite pillared clays are promising catalyst supports for carbon dioxide reforming of methane. The pore structure and surface properties of such supports greatly affect the catalytic behaviors of catalysts derived. Carbon deposition on catalysts was also affected by the property and structure of supports. The sintering of nickel metal and zirconia was another factor responsible for catalyst deactivation. This new-type nickel supported catalyst Ni/Zr-Laponite(8), with well-developed porosity, gave a higher initial conversion and a relatively long-term stability, and is therefore a promising catalyst for potential application to carbon dioxide reforming of methane to synthesis gas. (C) 2002 Elsevier Science B.V All rights reserved.