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The radioactive nuclide 225Ac is one of the few promising candidates for cancer treatment by targeted-α\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\alpha$$\end{document}-therapy, but worldwide production of 225Ac faces significant limitations. In this work, the Isotope Separation On-Line method was used to produce actinium by irradiating targets made of uranium carbide and thorium carbide with 1.4-GeV protons. Actinium fluoride molecules were formed, ionized through electron impact, then extracted and mass-separated as a beam of molecular ions. The composition of the mass-selected ion beam was verified using time-of-flight mass spectrometry, α\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\alpha$$\end{document}- and γ\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\gamma$$\end{document}-ray decay spectrometry. Extracted quantities of 225Ac19F2+\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$^{225}\textrm{Ac}^{19}\textrm{F}_2^{+}$$\end{document} particles per μ\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\upmu$$\end{document}C of incident protons were 3.9(3)×107\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$3.9(3)\times 10^7$$\end{document} from a uranium carbide target and 4.3(4)×107\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$4.3(4)\times 10^7$$\end{document} for a thorium carbide target. Using a magnetic mass separator, the long-lived contamination 227 Ac is suppressed to <5.47×10-7\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$<5.47\times 10^{-7}$$\end{document} (95% confidence interval) with respect to 225Ac by activity. Measured rates scale to collections of 108 kBqμ\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\upmu$$\end{document}A-1\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$^{-1}$$\end{document}h-1\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$^{-1}$$\end{document} of directly produced 225Ac19F2+\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$^{225}\textrm{Ac}^{19}\textrm{F}_2^{+}$$\end{document}. [ABSTRACT FROM AUTHOR]

Bioremediation is becoming an accepted treatment option for the remediation of petroleum-contaminated sites. Instrumental in implementingbioremediation is the characterization of bacteria capable of degrading the contaminants of interest. A wide variety of techniques have been reported in the literature but they often involve volatile solvents or petroleum mixtures as substrates and thus are difficult to use.Standard heterotrophic plate counts are often required by environmental regulations to be included as part of contaminated site investigations and assessments. Standard heterotrophic plate count techniques were found in this study to be unable to detect changes in populationsizes in contaminated and uncontaminated soils. A more specific assay using benzoate, a metabolite of many BTEX compounds, was also used.This technique was capable of detecting differences in population size between contaminated and uncontaminated soils and benzoate is thusa better substrate to use when characterizing petroleum-contaminatedsoils. Furthermore, the data (population size vs. contaminant concentration) fit a hyperbolic model well. Such a model could be used to monitor population size with respect to contaminant concentration as well as population size outside the contaminant plume to further assess the progress of bioremediation at a contaminated site. [ABSTRACT FROM AUTHOR]

A fundamental lack of data on the potential impacts of carbon based nanomaterials on natural ecosystems currently exists. The gap between what we know about environmental impacts and new products that may contain nanomaterials continues to get wider especially related to knowledge about nanocomposites. In this paper we present ideas and concerns about the current state of knowledge on nanomaterials in the environment and present a number of points about what recent work has provided us about the novel materials. [ABSTRACT FROM AUTHOR]