Alternative Sample Loading Preparation for Thermal Ionization Mass Spectrometry

This contribution describes a new sample loading method for Thermal Ionization Mass Spectrometry (TIMS), which is used in nuclear safeguards and non-proliferation efforts worldwide and is known as the “gold standard” in isotopic ratio measurements of plutonium. TIMS analysis is used to determine grades of nuclear material and the extent of enrichment at production sites. The current sample loading method for TIMS analysis is known as “bead-loading”. While it provides the lowest detection limit of any known method for plutonium analysis, bead-loading is a difficult, time consuming, and expensive method that results in up to 20% sample loss. The major encumbrance of the method is the need to manually place a small polymer bead (~40 μm diameter) containing the plutonium sample onto a narrow and fragile ionization filament. We have developed an alternative sample loading method that eliminates the difficult and time-consuming steps by pre-coating the ionization filaments with a thin polymer film. Sample loading times have been reduced from hours to minutes. The films remain stably anchored to the filament, thus preventing sample loss. Ongoing TIMS measurements are testing our hypothesis that the method will increase overall measurement efficiency/sensitivity by isolating the sample in close proximity to the filament

Community-based alternatives for justice-involved individuals with severe mental illness: Diversion, problem-solving courts, and reentry

a b s t r a c t a r t i c l e i n f o Available online 9 October 2012 Purpose: Adults with severe mental illness are overrepresented in the criminal justice system, and traditional criminal justice processing has not led to meaningful improvement in recidivism and other relevant outcomes. Fortunately, there has been considerable growth in community-based alternatives to standard prosecution for justice-involved adults with severe mental illness. The purpose of this article is to examine three such community-based alternatives -diversion, problem-solving courts, and reentry into the community -and offer best practice recommendations for developing, implementing, and refining these programs. Methods: The literature relating to the impetus and rationale for community-based alternatives, an organizing framework for conceptualizing the range of community-based alternatives, and the empirical evidence for community-based alternatives was reviewed. Results: Existing research on diversion, problem-solving courts, and reentry is generally inconsistent and lacking in uniformity. Although some community-based interventions have a great deal of empirical support, other interventions have received very little research attention. Conclusions: Research suggests that some community-based alternatives are an effective strategy for adults with severe mental illness, but more empirical research is needed before most community-based interventions can be described as empirically supported

Alternative Sample Loading Preparation for Thermal Ionization Mass Spectrometry

This contribution describes a new sample loading method for Thermal Ionization Mass Spectrometry (TIMS), which is used in nuclear safeguards and non-proliferation efforts worldwide and is known as the “gold standard†in isotopic ratio measurements of plutonium. TIMS analysis is used to determine grades of nuclear material and the extent of enrichment at production sites. The current sample loading method for TIMS analysis is known as “bead-loadingâ€. While it provides the lowest detection limit of any known method for plutonium analysis, bead-loading is a difficult, time consuming, and expensive method that results in up to 20% sample loss. The major encumbrance of the method is the need to manually place a small polymer bead (~40 μm diameter) containing the plutonium sample onto a narrow and fragile ionization filament. We have developed an alternative sample loading method that eliminates the difficult and time-consuming steps by pre-coating the ionization filaments with a thin polymer film. Sample loading times have been reduced from hours to minutes. The films remain stably anchored to the filament, thus preventing sample loss. Ongoing TIMS measurements are testing our hypothesis that the method will increase overall measurement efficiency/sensitivity by isolating the sample in close proximity to the filament