Application: Stand-off detection
Product: IRis-F1
M. Bredács, J. Geier, C. Barretta, R. Horvath, M. Geiser, K. Ander, G. Oreski and S. Gergely
Polymer Testing; 2023
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The high variety of tailor fitted molecular structures of polyethylene (PE) is very beneficial to fulfill requirements of various applications, however it poses a difficulty in the mechanical recycling of post-consumer PE products. To improve the quality of PE recyclates and increase the amounts of recyclates that can be used in new products, separation of PE waste by density and melt flow rate (MFR) during mechanical sorting is essential. Therefore, 25 virgin PE grades were used to manufacture compression molded plates that were then characterized by means of Attenuated Total Reflection - Fourier transformed IR (ATR-FTIR) and near IR (NIR) spectroscopy, NIR hyperspectral imaging and dual-comb spectroscopy. The results were used to build partial least squares regression (PLS) models to predict MFR and density. ATR-FTIR and laboratory NIR spectroscopy provided sufficient information to predict the density value of PE, whereas the MFR assessments was not possible. The PLS model from the industrial NIR data also only allowed the density-based classification of virgin PE grades. The PLS models built from transmission and reflectance dual comb spectroscopy infrared (DCS-IR) of selected samples clearly showed that density and MFR prediction can be carried out with high accuracy. As DCS-IR could be implemented on plastic sorting systems using a conveyor belt, the addition of this sensor in mechanical sorting line would lead to a significantly higher quality of recycled PE with narrow well-defined density and MFR ranges. Such an improvement would immensely support the targeted recycling rates and amount by the European Union and would make a significant step towards circular plastics.
Application: Stand-off detection
Product: IRis-F1
John Macarthur, Jakob Hayden, Matthew S. Warden, Christopher Carson, David M. Stothard, Vasili G. Savitski
IEEE Transactions on Instrumentation and Measurement; 2022
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Standoff scanning dual-comb spectroscopy of explosive materials is demonstrated with quantum cascade lasers at ∼8 μm . The proof-of-concept of the spectrometer, capable of the detection and identification of explosive materials at a distance of 3 m, has a detection limit of cyclotrimethylenetrinitramine (RDX) and pentaerythritol tetranitrate (PETN) on various surfaces of 5– 8 μg /cm^2 in a scanning regime and 2– 3 μg /cm^2 with stationary beam in reflection–absorption and backscattering modes.
Application: Stand-off detection
Product: IRis-F1
Hensley, Joel M.; Brown, Justin M.; Allen, Mark G.; Geiser, Markus; Allmendinger, Pitt; Mangold, Markus; Hugi, Andreas; Juoy, Pierre; Faist, Jérôme
Ultrafast Bandgap Photonics III; 2018
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Using dual optical frequency comb (OFC) spectroscopy in the longwave infrared (LWIR), we demonstrate standoff detection of trace amounts of target compounds on diffusely scattering surfaces. The OFC is based on quantum cascade lasers (QCL) that emit ~1 Watt of optical power under cw operation at room temperature over coherent comb bandwidths approaching 100 cm-1. We overlap two nearly identical 1250 cm-1 QCL OFC sources so that the two interfering optical combs create via heterodyne a single comb in the radio frequency (rf) that represents the entire optical spectrum in a single acquisition. In a laboratory scale demonstration we show detection of two spectrally distinct fluorinated silicone oils, poly(methyl-3,3,3-trifluoropropylsiloxane) and Krytox™, that act as LWIR simulants for security relevant compounds whose room temperature vapor pressure is too low to be detected in the gas phase. These target compounds are applied at mass loadings of 0.3 to 90 μg/cm2 to sanded aluminum surfaces. Only the diffusely scattered light is collected by a primary collection optic and focused onto a high speed (0.5 GHz bandwidth) thermoelectrically cooled mercury cadmium telluride (MCT) detector. At standoff distances of both 0.3 and 1 meter, we demonstrate 3 μg/cm2 and 1 μg/cm2 detection limits against poly(methyl-3,3,3-trifluoropropylsiloxane) and Krytox™, respectively.