A second generation prototype enabling surface plasmon resonance spectroscopic measurements in the infrared (IR) range is described. The new design (v2) uses the optical train (optics and detector) within conventional FT-IR spectrometers by confining dimensions of the accessory to space available within the sample compartment of the spectrometer. The v2 accessory builds upon knowledge gained from a previous version that was based on a modified commercial variable angle spectroscopic accessory and addresses observed limitations of the original design-improved temporal stability and measurement acquisition speed, crucial to biomolecular binding studies, as well as optical flexibility, a requirement for investigations of novel plasmon-supporting materials.
View Article and Find Full Text PDFJ Vasc Interv Radiol
October 2008
Purpose: To describe clinical outcomes of endovascular interventions in the setting of thrombosis or dysfunction of anterior chest wall ("necklace") arteriovenous (AV) hemodialysis grafts.
Materials And Methods: Eight percutaneous interventions (balloon angioplasty, pharmacologic thrombolysis, and mechanical thrombectomy) were performed in five patients with anterior chest wall AV grafts. Primary, assisted, and secondary patencies, as well as technical success and complication rates, were determined.
Turbidimetric method (TM), ion chromatography (IC) and inductively coupled plasma atomic emission spectrometry (ICP-AES) with and without acid digestion have been compared and validated for the determination of sulfate in mining wastewater. Analytical methods were chosen to compare the performance of a portable field turbidimetric instrument and to validate the underlying assumption utilized in conversion of total sulfur to sulfate during ICP-AES analysis. Accuracy and precision of analytical techniques were compared to one another using control and field samples collected from a mine site using the Bonferroni multiple comparison test.
View Article and Find Full Text PDFEvaluation of metal leaching using a single leach test such as the Toxicity Characteristic Leaching Procedure (TCLP) is often questionable. The pH, redox potential (E(h)), particle size and contact time are critical variables in controlling metal stability, not accounted for in the TCLP. This paper compares the leaching behavior of metals in mineral processing waste via short-term extraction tests such as TCLP, Field Leach Test (FLT) used by USGS and deionized water extraction tests.
View Article and Find Full Text PDFSci Total Environ
November 2005
Determining the effectiveness of in situ immobilization for P-amended, Pb-contaminated soils has typically relied on non-spectroscopic methods. However in recent years, these methods have come under scrutiny due to technical and unforeseen error issues. In this study, we analyzed 18 soil samples via X-ray diffraction (XRD), selective sequential extraction (SSE), and a physiologically based extraction test (PBET).
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