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Malinen J.,VTT Technical Research Center of Finland | Saari H.,VTT Technical Research Center of Finland | Kemeny G.,8505 University Green | Shi Z.,Duquesne University | Anderson C.,Duquesne University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

This paper reports instrument characterization measurements, which were recently arranged to provide comparative information on different hyperspectral chemical imaging systems. Three different instruments were studied covering both tunable filter and push-broom techniques: The first instrument MatrixNIR™ is based on a LCTF tunable filter and InGaAs camera and covers wavelengths from 1000 to 1700 nm. The second one SisuCHEMA™ is based on push-broom technology and MCT camera operating from 1000 to 2500 nm. The third system is an instrument prototype from VTT Technical Research Centre of Finland exploiting high speed Fabry-Perot interferometer and MCT camera, currently calibrated from 1260 to 2500 nm. The characterization procedure was designed to study instrumental noise, signal-to-noise ratio, linearity and spectral as well as spatial resolution. Finally, a pharmaceutical tablet sample was measured with each instrument to demonstrate speed of measurement in a typical application. In spite of differences in wavelength ranges and camera technologies used, the results provide interesting information on relative instrumental advantages and disadvantages, which may be useful for selecting appropriate instrumentation for defined applications. Further, an additional aim of this study is to compare the high speed Fabry-Perot imaging technology under development against the established chemical imaging techniques available on the market today. © 2010 Copyright SPIE - The International Society for Optical Engineering. Source

Elhajjar R.F.,University of Wisconsin - Milwaukee | Shams S.S.,University of Wisconsin - Milwaukee | Kemeny G.J.,8505 University Green | Stuessy G.,8505 University Green
Composites Part A: Applied Science and Manufacturing | Year: 2016

In this study, a hybrid approach coupling hyperspectral near infrared imaging with a progressive finite element method is proposed for characterization of the elastic and failure response of composites with non-uniform variations of the wrinkles profile through the thickness and across the structure dimensions. In this approach, hyperspectral near infrared spectroscopy is used to create a 3D profile of the surface resin pockets with the capability of measuring resin thickness from approximately 125 to 2500 μm. These resin pockets are directly correlated to underlying ply level wrinkling as confirmed by optical microscopy. The 3D mapped resin plane obtained from the hyperspectral imaging is used to morph a ply-by-ply finite element model of a carbon-fiber/epoxy resin laminated plate using a progressive damage failure methodology. The results show the capability of the hybrid method to predict the structural response in laminated composites containing spatially distributed and non-uniform ply-level wrinkling. © 2015 Elsevier Ltd. All rights reserved. Source

Osorio J.G.,Rutgers University | Stuessy G.,8505 University Green | Kemeny G.J.,8505 University Green | Muzzio F.J.,Rutgers University
Chemical Engineering and Processing: Process Intensification | Year: 2016

This paper compares the micro-mixing dynamics of three active pharmaceutical ingredients (APIs) varying in particle size, bulk density and cohesion. Chlorpheniramine maleate, acetaminophen and caffeine, in a common blend of excipients, were used in this study. Micro-mixing was studied in a 1-L bin-blender using in-line near infrared chemical imaging (NIR-CI) to monitor the aggregate size distribution of the APIs and excipients. A science-based calibration chemometric method was used to calculate the concentration maps of ingredients in the blends. Chlorpheniramine maleate, smallest in particle size with lowest bulk density, resulted in the highest relative standard deviation (RSD) for all concentrations. The RSDs obtained for acetaminophen and caffeine were similar and dependent on their concentrations. Chlorpheniramine remained in large aggregates throughout the blending process. Overall, other ingredients (e.g. Avicel) required longer blending times to become well dispersed in the presence of chlorpheniramine maleate, as evidenced by the aggregate size measurements. This in-line NIR-CI technique was able to approximate the number of API aggregates and their size during a common blending process. Although further development of this technique is necessary, metrics measured using this technique could potentially be used as a critical quality attributes during pharmaceutical processing. © 2016 Elsevier B.V. Source

Osorio J.G.,Rutgers University | Stuessy G.,8505 University Green | Kemeny G.J.,8505 University Green | Muzzio F.J.,Rutgers University
Chemical Engineering Science | Year: 2014

The present study introduces a new in situ near-infrared chemical imaging technique (imMixTM) designed to characterize micro-mixing in pharmaceutical powder blends. The technique uses in-line, non-contact monitoring of the blending process, eliminating the bias introduced by commonly used powder sampling techniques. A Science-Based Calibration (SBC) chemometric method, which uses pure component spectral data to create a calibration model, was used to create concentration maps of the blends studied here. The advantage of SBC over the alternative Partial Least Squares (PLS) or Principal Component Analysis (PCA) calibration methods is that it does not require a large number of samples to create a calibration. The imMix system proved to be useful in monitoring the spatial distribution and aggregate sizes of acetaminophen, used as the model drug, and of excipients in the blends. Using a 1-l bin-blender, measurements were able to detect changes in the constituents and other experimental parameters as a function of blending time. Such measurements can be used to determine the mixing time and shear requirements of blends during product and process development. © 2013 Elsevier Ltd. Source

Shelley P.H.,Boeing Company | Werner G.J.,Boeing Company | Vahey P.G.,Boeing Company | Kemeny G.J.,8505 University Green | And 3 more authors.
International SAMPE Technical Conference | Year: 2014

Excess resin on the surface of composite structural materials can affect performance of the underlying structure. One example is a resin filled pocket in a surface wrinkle in cured composite. Even if the wrinkle is visible, it is not currently possible to determine its depth non-destructively. In other cases, excess resin on the composite surface might result from a wrinkle in the bagging material, so there is no underlying composite feature. NDI methods based on ultrasound can detect resin pockets in excess of 0.040 inches (40 mils) deep but cannot accurately measure their depth. Until now there has been no reliable method for detecting resin pockets in the 5 to 40 mil range. Near Infrared (NIR) imaging can accurately measure surface resin on composite materials from 2 to 75 mils thick, detecting virtually all resin pockets, resin filled surface wrinkles and other surface resin features. NIR imaging can measure resin feature location, width, length and the structually important width/depth ratio. Copyright 2014 by Boeing Research and Technology and Middleton Research. Source

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