Separation and quantification of 238U, 232Th and rare earths in monazite samples by ion chromatography coupled with on-line flow scintillation detector.
An alternative procedure has been described for efficient separation and quantitative determination of uranium (U), thorium (Th) and rare earth elements (REEs) in monazite mineral by high performance ion chromatographic system (IC). Different variables affecting the distribution coefficient, the retention and hence separation efficiency such as eluent flow rate and concentrations of HCI and ammonium sulfate (NH4)2SO4 containing the mobile phase were studied. The developed separation protocol of U, Th and REEs was optimized using an Ion Pac CS5 separation column followed by post-column derivatization reaction with Arsenaso III and UV-VIS spectrophotometric detection. Comparative evaluation of U, Th and REEs concentration in monazite mineral was demonstrated using two different on-line detection modes including flow through cell scintillation detector (FSD) and UV-VIS spectrophotometer. Response of the FSD was found to be linear over the full range of activities investigated (4-100 Bq). The lower limits of detection (LLD) for the investigated radionuclides were 3.0+0.1 Bq for 238U and 6.0 +/- 0.1 Bq for 232Th. The detection of 238U and 232Th by FSD shows good agreement with the corresponding determination by UV-VIS spectrophotometer. The content of ThO2 and U3O8 in monazite sample were found to be 4.7 +/- 0.1% and 0.42 +/- 0.04% using UV-VIS detector and 4.3 +/- 0.1% and 0.45 +/- 0.1% using FSD, respectively.
Fluorescent BINOL-based sensor for thorium recognition and a density functional theory investigation.
A novel 1,1'-bi-2-naphthol (BINOL) derivative fluorescence sensor L-1 for the recognition of thorium ion with a fluorescence quench response. This ligand showed high selectivity and sensitivity for thorium ion recognition. Coordination effects were investigated by DFT calculations, and the coordination modes and sites were confirmed. Moreover, the coordination abilities of the L-1 ligand with Th(4+) and UO2(2+) were evaluated.
Religious Ethics and Active Euthanasia in a Pluralistic Society
This article sets out a descriptive typology of religious perspectives on legalized euthanasia—political advocacy, individual conscience, silence, embedded opposition, and formal public opposition—and then examines the normative basis for these perspectives through the themes of sovereignty, stewardship, and the self. It also explores the public relevance of these religious perspectives for debates over legalized euthanasia, particularly in the realm of public policy. Ironically, the moral discourse of religious traditions on euthanasia may gain public relevance at the expense of its religious content. Nonetheless, religious traditions can provide a context of ultimacy and meaning to this debate, which is a condition for genuine pluralism. A table setting out the views of various denominations with regard to euthanasia is included.