The Experts below are selected from a list of 327 Experts worldwide ranked by ideXlab platform
C. Pechyen - One of the best experts on this subject based on the ideXlab platform.
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Development and characterization of Poly (lactic acid)/fish water soluble protein composite sheets: A potential approach for biodegradable packaging
Energy Procedia, 2014Co-Authors: Rapeepan Saiwaew, Panuwat Suppakul, Waraporn Boonsupthip, C. PechyenAbstract:Fish water soluble protein was enhanced to thermoplastic prior compounding with Poly (lactic acid) (PLA) using twin screw extruder. A large quantity of water as solvent and oleic acid as plasticizer were incorporated using plasticization (FWSP-ole). Effect of the formulated FWSP-ole concentration, oleic acid and maleic anhydride on the morphology, thermal behavior, mechanical, and permeability of PLA/FWSP-ole composite sheets was studied using scanning electron microscope (SEM) differential scanning microscope (DSC), a universal testing machine and water vapor permeation analyzer, respectively. The results demonstrated that FWSP-ole content resulted in tensile strength increase from 5.33±0.95 MPa (5FWSP-ole) to 11.88±1.82 MPa (10FWSP-ole) but elongation at break was not different. Addition of oleic acid during extrusion process caused extremely increase of elongation at break at 462.96% but a lot of pinhole into composite matrix occurred. On the contrary, maleic anhydride caused reduction size and stretching phase of FWSP resulting in good interfacial adhesion resulting in reduction of Pinholes and water vapor permeability. The latest is food contact approved and focused on thermoforming molding application.
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11th eco energy and materials science and engineering 11th emses development and characterization of poly lactic acid fish water soluble protein composite sheets a potential approach for biodegradable packaging
2014Co-Authors: Rapeepan Saiwaew, Panuwat Suppakul, Waraporn Boonsupthip, C. PechyenAbstract:Fish water soluble protein was enhanced to thermoplastic prior compounding with Poly (lactic acid) (PLA) using twin screw extruder. A large quantity of water as solvent and oleic acid as plasticizer were incorporated using plasticization (FWSP-ole). Effect of the formulated FWSP-ole concentration, oleic acid and maleic anhydride on the morphology, thermal behavior, m echanical, and permeability of PLA/FWSP-ole composite sheets was studied using scanning electron microscope (SEM) differential scanning microscope (DSC), a universal testing machine and water vapor permeation analyzer, respectively. The results demonstrated that FWSP-ole content resulted in tensile strength increase from 5.33±0.95 MPa (5FWSP-ole) to 11.88±1.82 MPa (10FWSP-ole) but elongation at break was not different. Addition of oleic acid during extrusion process caused extremely increase of elongation at break at 462.96% but a lot of pinhole into composite matrix occurred. On the contrary, maleic anhydride caused reduction size and stretching phase of FWSP resulting in good interfacial adhesion resulting in reduction of Pinholes and water vapor permeability. The latest is food contact approved and focused on thermoforming molding application. © 2014 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of COE of Sustainalble Energy System, Rajamangala University of Technology Thanyaburi (RMUTT).
Felix N Buchi - One of the best experts on this subject based on the ideXlab platform.
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factors determining the gas crossover through Pinholes in polymer electrolyte fuel cell membranes
Electrochimica Acta, 2012Co-Authors: Stefan Kreitmeier, Matteo Michiardi, Alexander Wokaun, Felix N BuchiAbstract:Abstract Membrane degradation in polymer electrolyte fuel cells often results in pinhole formation, which does not force an immediate fuel cell shutdown, as the performance is still good and the gas crossover is moderate for low membrane defect densities. However, the gas crossover increases locally at defects, which may accelerate chemical polymer decomposition and enlarge the defect. Hence, a fundamental understanding of the gas crossover through small Pinholes is required to deduce strategies mitigating fast membrane degradation. Methods are developed to implement Pinholes (10 μm) artificially in polymer electrolyte membranes. The pinhole morphology and chemical environment are characterized by X-ray tomographic microscopy and FTIR spectro-microscopy. The gas crossover is measured in situ for different fuel cell operating conditions using a mass spectrometry based method. In saturated environment liquid water can seal Pinholes and eliminate the crossover. This sealing effect depends on the pinhole size and the pressure gradient between anode and cathode. Increasing temperature or humidity reduces the gas crossover. Hydrogen, permeating through defects, does not oxidize quantitatively at the cathode catalyst layer, but permeates through the gas diffusion layer (GDL) into the gas channel. Then, the permeability of the GDL, in particular its micro-porous layer, limits the gas crossover through Pinholes significantly.
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Factors determining the gas crossover through Pinholes in polymer electrolyte fuel cell membranes
Electrochimica Acta, 2012Co-Authors: Stefan Kreitmeier, Matteo Michiardi, Alexander Wokaun, Felix N BuchiAbstract:Membrane degradation in polymer electrolyte fuel cells often results in pinhole formation, which does not force an immediate fuel cell shutdown, as the performance is still good and the gas crossover is moderate for low membrane defect densities. However, the gas crossover increases locally at defects, which may accelerate chemical polymer decomposition and enlarge the defect. Hence, a fundamental understanding of the gas crossover through small Pinholes is required to deduce strategies mitigating fast membrane degradation. Methods are developed to implement Pinholes (10 μm) artificially in polymer electrolyte membranes. The pinhole morphology and chemical environment are characterized by X-ray tomographic microscopy and FTIR spectro-microscopy. The gas crossover is measured in situ for different fuel cell operating conditions using a mass spectrometry based method. In saturated environment liquid water can seal Pinholes and eliminate the crossover. This sealing effect depends on the pinhole size and the pressure gradient between anode and cathode. Increasing temperature or humidity reduces the gas crossover. Hydrogen, permeating through defects, does not oxidize quantitatively at the cathode catalyst layer, but permeates through the gas diffusion layer (GDL) into the gas channel. Then, the permeability of the GDL, in particular its micro-porous layer, limits the gas crossover through Pinholes significantly. © 2012 Elsevier Ltd.
Rapeepan Saiwaew - One of the best experts on this subject based on the ideXlab platform.
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Development and characterization of Poly (lactic acid)/fish water soluble protein composite sheets: A potential approach for biodegradable packaging
Energy Procedia, 2014Co-Authors: Rapeepan Saiwaew, Panuwat Suppakul, Waraporn Boonsupthip, C. PechyenAbstract:Fish water soluble protein was enhanced to thermoplastic prior compounding with Poly (lactic acid) (PLA) using twin screw extruder. A large quantity of water as solvent and oleic acid as plasticizer were incorporated using plasticization (FWSP-ole). Effect of the formulated FWSP-ole concentration, oleic acid and maleic anhydride on the morphology, thermal behavior, mechanical, and permeability of PLA/FWSP-ole composite sheets was studied using scanning electron microscope (SEM) differential scanning microscope (DSC), a universal testing machine and water vapor permeation analyzer, respectively. The results demonstrated that FWSP-ole content resulted in tensile strength increase from 5.33±0.95 MPa (5FWSP-ole) to 11.88±1.82 MPa (10FWSP-ole) but elongation at break was not different. Addition of oleic acid during extrusion process caused extremely increase of elongation at break at 462.96% but a lot of pinhole into composite matrix occurred. On the contrary, maleic anhydride caused reduction size and stretching phase of FWSP resulting in good interfacial adhesion resulting in reduction of Pinholes and water vapor permeability. The latest is food contact approved and focused on thermoforming molding application.
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11th eco energy and materials science and engineering 11th emses development and characterization of poly lactic acid fish water soluble protein composite sheets a potential approach for biodegradable packaging
2014Co-Authors: Rapeepan Saiwaew, Panuwat Suppakul, Waraporn Boonsupthip, C. PechyenAbstract:Fish water soluble protein was enhanced to thermoplastic prior compounding with Poly (lactic acid) (PLA) using twin screw extruder. A large quantity of water as solvent and oleic acid as plasticizer were incorporated using plasticization (FWSP-ole). Effect of the formulated FWSP-ole concentration, oleic acid and maleic anhydride on the morphology, thermal behavior, m echanical, and permeability of PLA/FWSP-ole composite sheets was studied using scanning electron microscope (SEM) differential scanning microscope (DSC), a universal testing machine and water vapor permeation analyzer, respectively. The results demonstrated that FWSP-ole content resulted in tensile strength increase from 5.33±0.95 MPa (5FWSP-ole) to 11.88±1.82 MPa (10FWSP-ole) but elongation at break was not different. Addition of oleic acid during extrusion process caused extremely increase of elongation at break at 462.96% but a lot of pinhole into composite matrix occurred. On the contrary, maleic anhydride caused reduction size and stretching phase of FWSP resulting in good interfacial adhesion resulting in reduction of Pinholes and water vapor permeability. The latest is food contact approved and focused on thermoforming molding application. © 2014 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of COE of Sustainalble Energy System, Rajamangala University of Technology Thanyaburi (RMUTT).
Stefan Kreitmeier - One of the best experts on this subject based on the ideXlab platform.
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factors determining the gas crossover through Pinholes in polymer electrolyte fuel cell membranes
Electrochimica Acta, 2012Co-Authors: Stefan Kreitmeier, Matteo Michiardi, Alexander Wokaun, Felix N BuchiAbstract:Abstract Membrane degradation in polymer electrolyte fuel cells often results in pinhole formation, which does not force an immediate fuel cell shutdown, as the performance is still good and the gas crossover is moderate for low membrane defect densities. However, the gas crossover increases locally at defects, which may accelerate chemical polymer decomposition and enlarge the defect. Hence, a fundamental understanding of the gas crossover through small Pinholes is required to deduce strategies mitigating fast membrane degradation. Methods are developed to implement Pinholes (10 μm) artificially in polymer electrolyte membranes. The pinhole morphology and chemical environment are characterized by X-ray tomographic microscopy and FTIR spectro-microscopy. The gas crossover is measured in situ for different fuel cell operating conditions using a mass spectrometry based method. In saturated environment liquid water can seal Pinholes and eliminate the crossover. This sealing effect depends on the pinhole size and the pressure gradient between anode and cathode. Increasing temperature or humidity reduces the gas crossover. Hydrogen, permeating through defects, does not oxidize quantitatively at the cathode catalyst layer, but permeates through the gas diffusion layer (GDL) into the gas channel. Then, the permeability of the GDL, in particular its micro-porous layer, limits the gas crossover through Pinholes significantly.
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Factors determining the gas crossover through Pinholes in polymer electrolyte fuel cell membranes
Electrochimica Acta, 2012Co-Authors: Stefan Kreitmeier, Matteo Michiardi, Alexander Wokaun, Felix N BuchiAbstract:Membrane degradation in polymer electrolyte fuel cells often results in pinhole formation, which does not force an immediate fuel cell shutdown, as the performance is still good and the gas crossover is moderate for low membrane defect densities. However, the gas crossover increases locally at defects, which may accelerate chemical polymer decomposition and enlarge the defect. Hence, a fundamental understanding of the gas crossover through small Pinholes is required to deduce strategies mitigating fast membrane degradation. Methods are developed to implement Pinholes (10 μm) artificially in polymer electrolyte membranes. The pinhole morphology and chemical environment are characterized by X-ray tomographic microscopy and FTIR spectro-microscopy. The gas crossover is measured in situ for different fuel cell operating conditions using a mass spectrometry based method. In saturated environment liquid water can seal Pinholes and eliminate the crossover. This sealing effect depends on the pinhole size and the pressure gradient between anode and cathode. Increasing temperature or humidity reduces the gas crossover. Hydrogen, permeating through defects, does not oxidize quantitatively at the cathode catalyst layer, but permeates through the gas diffusion layer (GDL) into the gas channel. Then, the permeability of the GDL, in particular its micro-porous layer, limits the gas crossover through Pinholes significantly. © 2012 Elsevier Ltd.
Paul D Acton - One of the best experts on this subject based on the ideXlab platform.
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optimal number of Pinholes in multi pinhole spect for mouse brain imaging a simulation study
Physics in Medicine and Biology, 2005Co-Authors: R Accorsi, Paul D ActonAbstract:This study simulates a multi-pinhole single-photon emission computed tomography (SPECT) system using the Monte Carlo method, and investigates different multi-pinhole designs for quantitative mouse brain imaging. Prior approaches investigating multi-pinhole SPECT were not often optimal, as the number and geometrical arrangement of Pinholes were usually chosen empirically. The present study seeks to optimize the number of Pinholes for a given pinhole arrangement, and also for the specific application of quantitative neuroreceptor binding in the mouse brain. An analytical Monte Carlo simulation based method was used to generate the projection data for various count levels. A three-dimensional ordered-subsets expectation-maximization algorithm was developed and used to reconstruct the images, incorporating a realistic pinhole model for resolution recovery and noise reduction. Although artefacts arising from overlapping projections could be a major problem in multi-pinhole reconstruction, the cold-rod phantom study showed minimal loss of spatial resolution in multi-pinhole systems, compared to a single-pinhole system with the same pinhole diameter. A quantitative study of neuroreceptor binding sites using a mouse brain phantom and low activity (37 MBq) showed that the multi-pinhole system outperformed the single-pinhole system by maintaining the mean and lowering the variance in the measured uptake ratio. Multi-pinhole collimation can be used to reduce the injected dose and thereby reduce the radiation exposure to the animal. Results also suggest that the nine-pinhole configuration shown in this paper is a good choice for mouse brain imaging.
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Optimal number of Pinholes in multi-pinhole SPECT for mouse brain imaging—a simulation study
Physics in Medicine and Biology, 2005Co-Authors: R Accorsi, Paul D ActonAbstract:This study simulates a multi-pinhole single-photon emission computed tomography (SPECT) system using the Monte Carlo method, and investigates different multi-pinhole designs for quantitative mouse brain imaging. Prior approaches investigating multi-pinhole SPECT were not often optimal, as the number and geometrical arrangement of Pinholes were usually chosen empirically. The present study seeks to optimize the number of Pinholes for a given pinhole arrangement, and also for the specific application of quantitative neuroreceptor binding in the mouse brain. An analytical Monte Carlo simulation based method was used to generate the projection data for various count levels. A three-dimensional ordered-subsets expectation-maximization algorithm was developed and used to reconstruct the images, incorporating a realistic pinhole model for resolution recovery and noise reduction. Although artefacts arising from overlapping projections could be a major problem in multi-pinhole reconstruction, the cold-rod phantom study showed minimal loss of spatial resolution in multi-pinhole systems, compared to a single-pinhole system with the same pinhole diameter. A quantitative study of neuroreceptor binding sites using a mouse brain phantom and low activity (37 MBq) showed that the multi-pinhole system outperformed the single-pinhole system by maintaining the mean and lowering the variance in the measured uptake ratio. Multi-pinhole collimation can be used to reduce the injected dose and thereby reduce the radiation exposure to the animal. Results also suggest that the nine-pinhole configuration shown in this paper is a good choice for mouse brain imaging.
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Pinhole PET (pPET): a multi-pinhole collimator insert for small animal SPECT imaging on PET cameras
IEEE Nuclear Science Symposium Conference Record 2005, 2005Co-Authors: Christopher Cardi, Mathew L. Thakur, Joel S. Karp, Paul D ActonAbstract:To effectively study small animal models of disease in vivo a wide range of PET and SPECT imaging agents need to be employed. In an effort to achieve high resolution and high sensitivity small animal SPECT imaging we propose the notion of using a multiple pinhole insert in a PET scanner (pPET). Adapting PET scanners to enable pinhole SPECT imaging is an attractive solution for many reasons. Most PET systems are full ring detectors which offer the potential for pinhole configurations that fully sample an object without the need for complex detector rotation. Dual modality studies can be performed without moving the subject providing perfect spatial alignment. Furthermore, enabling SPECT imaging in a PET scanner makes financial sense by reducing the initial investment and maintenance costs. In this study we prove the feasibility of using a pinhole insert to enable SPECT imaging in PET scanners. Simulations performed using the geometry of the Mosaic (Philips), a dedicated small animal PET scanner (Rdet=98.5 mm), show a variety of attractive pinhole configurations offering a blend of resolution (to under 1.0 mm), sensitivity (up to 0.5%), field of view (up to 40 mm) and good image quality. Measurements with the Mosaic demonstrate that by raising the high voltage, to account for the lower light output, 140 keV gammas can be efficiently detected and adequately positioned for both GSO (gadolinium oxyorthosilicate) and LYSO (lutetium yttrium orthosilicate) scintillators. Initial imaging studies with a 12/spl times/1 (holes /spl times/ rows) collimator with 1.0 mm Pinholes at a 30 mm radius demonstrate the feasibility and show promising resolution (1.5 mm FWHM), good image quality, and a relatively large field of view.
