The Experts below are selected from a list of 107535 Experts worldwide ranked by ideXlab platform
Johannis Simitzis - One of the best experts on this subject based on the ideXlab platform.
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Surface properties of PAN-based carbon Fibers tuned by anodic oxidation in different alkaline electrolyte systems
Applied Surface Science, 1999Co-Authors: Alexander Bismarck, M. E. Kumru, Jurgen Springer, Johannis SimitzisAbstract:High modulus carbon Fibers were anodic oxidized in various alkaline electrolyte systems. The success of the modification was proved by contact angle measurements. The Fiber surface tension was calculated from the measured contact angles using the harmonic mean method. With the exception of one electrolyte system, all in alkaline electrolytes modified carbon Fibers showed an Increased Fiber surface tension. The Increased Fiber surface tension is due to the Increased number of oxygen containing surface groups detected by energy dispersive X-ray microanalysis (EDX). Anodic oxidation causes a roughening of the Fiber surfaces observed by scanning electron microscopy (SEM). Cyclo-voltammetric investigations give an possible mechanism of the anodic oxidation in alkaline electrolytes. (C) 1999 Elsevier Science B.V. All rights reserved
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Surface properties of PAN-based carbon Fibers tuned by anodic oxidation in different alkaline electrolyte systems
Applied Surface Science, 1999Co-Authors: Alexander Bismarck, M. E. Kumru, Jurgen Springer, Johannis SimitzisAbstract:High modulus carbon Fibers were anodic oxidized in various alkaline electrolyte systems. The success of the modification was proved by contact angle measurements. The Fiber surface tension was calculated from the measured contact angles using the harmonic mean method. With the exception of one electrolyte system, all in alkaline electrolytes modified carbon Fibers showed an Increased Fiber surface tension. The Increased Fiber surface tension is due to the Increased number of oxygen containing surface groups detected by energy dispersive X-ray microanalysis (EDX). Anodic oxidation causes a roughening of the Fiber surfaces observed by scanning electron microscopy (SEM). Cyclo-voltammetric investigations give an possible mechanism of the anodic oxidation in alkaline electrolytes.
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Surface properties of PAN-based carbon Fibers tuned by anodic oxidation in different alkaline electrolyte systems
Applied Surface Science, 1999Co-Authors: Alexander Bismarck, M. E. Kumru, Jurgen Springer, Johannis SimitzisAbstract:High modulus carbon Fibers were anodic oxidized in various alkaline electrolyte systems. The success of the modification was proved by contact angle measurements. The Fiber surface tension was calculated from the measured contact angles using the harmonic mean method. With the exception of one electrolyte system, all in alkaline electrolytes modified carbon Fibers showed an Increased Fiber surface tension. The Increased Fiber surface tension is due to the Increased number of oxygen containing surface groups detected by energy dispersive X-ray microanalysis (EDX). Anodic oxidation causes a roughening of the Fiber surfaces observed by scanning electron microscopy (SEM). Cyclo-voltammetric investigations give an possible mechanism of the anodic oxidation in alkaline electrolytes.
Lawrence T Drzal - One of the best experts on this subject based on the ideXlab platform.
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toughening of carbon Fiber reinforced epoxy polymer composites utilizing Fiber surface treatment and sizing
Composites Part A-applied Science and Manufacturing, 2016Co-Authors: Markus A Downey, Lawrence T DrzalAbstract:Abstract Toughening of Fiber-reinforced epoxy composites while maintaining other mechanical properties represents a significant challenge. This paper presents an approach of enhancing the toughness of a DGEBA/mPDA-based carbon Fiber-reinforced epoxy composite, without significantly reducing the static-mechanical properties such as flexural properties and glass transition temperature. The impact of combining an UV-ozone Fiber surface treatment with an aromatic and aliphatic epoxy Fiber sizing on composite toughness is investigated. Carbon Fiber-epoxy adhesion was Increased as measured by the single Fiber interfacial shear test. The Mode I composite fracture toughness was enhanced by 23% for the UV-ozone Fiber surface treatment alone. With the addition of an aromatic and aliphatic Fiber sizing, the composite fracture toughness was further Increased to 50% and 84% respectively over the as-received, unsized Fiber. The Increased Fiber/matrix adhesion also improved the transverse flexural strength.
Alexander Bismarck - One of the best experts on this subject based on the ideXlab platform.
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Surface properties of PAN-based carbon Fibers tuned by anodic oxidation in different alkaline electrolyte systems
Applied Surface Science, 1999Co-Authors: Alexander Bismarck, M. E. Kumru, Jurgen Springer, Johannis SimitzisAbstract:High modulus carbon Fibers were anodic oxidized in various alkaline electrolyte systems. The success of the modification was proved by contact angle measurements. The Fiber surface tension was calculated from the measured contact angles using the harmonic mean method. With the exception of one electrolyte system, all in alkaline electrolytes modified carbon Fibers showed an Increased Fiber surface tension. The Increased Fiber surface tension is due to the Increased number of oxygen containing surface groups detected by energy dispersive X-ray microanalysis (EDX). Anodic oxidation causes a roughening of the Fiber surfaces observed by scanning electron microscopy (SEM). Cyclo-voltammetric investigations give an possible mechanism of the anodic oxidation in alkaline electrolytes. (C) 1999 Elsevier Science B.V. All rights reserved
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Surface properties of PAN-based carbon Fibers tuned by anodic oxidation in different alkaline electrolyte systems
Applied Surface Science, 1999Co-Authors: Alexander Bismarck, M. E. Kumru, Jurgen Springer, Johannis SimitzisAbstract:High modulus carbon Fibers were anodic oxidized in various alkaline electrolyte systems. The success of the modification was proved by contact angle measurements. The Fiber surface tension was calculated from the measured contact angles using the harmonic mean method. With the exception of one electrolyte system, all in alkaline electrolytes modified carbon Fibers showed an Increased Fiber surface tension. The Increased Fiber surface tension is due to the Increased number of oxygen containing surface groups detected by energy dispersive X-ray microanalysis (EDX). Anodic oxidation causes a roughening of the Fiber surfaces observed by scanning electron microscopy (SEM). Cyclo-voltammetric investigations give an possible mechanism of the anodic oxidation in alkaline electrolytes.
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Surface properties of PAN-based carbon Fibers tuned by anodic oxidation in different alkaline electrolyte systems
Applied Surface Science, 1999Co-Authors: Alexander Bismarck, M. E. Kumru, Jurgen Springer, Johannis SimitzisAbstract:High modulus carbon Fibers were anodic oxidized in various alkaline electrolyte systems. The success of the modification was proved by contact angle measurements. The Fiber surface tension was calculated from the measured contact angles using the harmonic mean method. With the exception of one electrolyte system, all in alkaline electrolytes modified carbon Fibers showed an Increased Fiber surface tension. The Increased Fiber surface tension is due to the Increased number of oxygen containing surface groups detected by energy dispersive X-ray microanalysis (EDX). Anodic oxidation causes a roughening of the Fiber surfaces observed by scanning electron microscopy (SEM). Cyclo-voltammetric investigations give an possible mechanism of the anodic oxidation in alkaline electrolytes.
Irena Hausmanowa-petrusewicz - One of the best experts on this subject based on the ideXlab platform.
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Atypical motor unit potentials in Emery-Dreifuss muscular dystrophy (EDMD).
Clinical Neurophysiology, 2005Co-Authors: K Rowińska-marcińska, Ewa Zalewska, Elzbieta Szmidt-salkowska, Anna Fidziańska, M. Dorobek, A. Karwańska, Irena Hausmanowa-petrusewiczAbstract:Abstract Objective The aim of the study was to analyse electromyographic changes in Emery–Dreifuss muscular dystrophy (EDMD) that are atypical for myopathy. Our special interest was focused on high amplitude polyphasic motor unit potentials (MUPs), also termed irregular MUPs. Methods We studied 21 EDMD patients with the diagnosis based on clinical data, DNA analysis and immunohistochemical muscle studies. Rectus femoris muscle biopsies were investigated in all affected patients. Electrophysiological investigations involved quantitative concentric needle electromyography (CNEMG) of biceps brachii (BB) and rectus femoris (RF) muscles. Simulation studies were performed to approximate the number, diameter and distribution of muscle Fibers, which contribute to irregular MUPs. Results The EMG data in EDMD were compatible with myopathy. Irregular MUPs showed longer duration, larger area, size index and higher amplitude then simple ones ( P 55μm) diameters than normal (50±5μm). Muscle biopsy specimens revealed the variable muscle Fiber size due to atrophy, hypertrophy, and muscle Fiber splitting. Conclusions Irregular MUPs recorded in EDMD are due to hypertrophied and atrophied Fibers as well as Increased Fiber density. They reflect reorganization of the motor unit in a slow progression myopathic process (muscle Fiber hypertrophy and splitting). Significance Irregular MUPs in EDMD most probably reflect Increased variability of the muscle Fiber size.
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Modeling studies on irregular motor unit potentials.
Clinical Neurophysiology, 2004Co-Authors: Ewa Zalewska, Irena Hausmanowa-petrusewicz, Erik StålbergAbstract:Abstract Objective : The aim of these modeling studies on the generation of motor unit potentials (MUPs) was to establish the influence of MU parameters and recording conditions on the shape irregularity of MUPs. The focus was on the dependence of the irregularity of MUPs on Fiber density, Fiber diameters and the recording distance from the end-plate zone. Methods : The study was performed using the ‘EMG Simulator’ software for modeling of MUP and our own software for calculations. Results : The results indicate that the irregularity of a MUP increases with Increased recording distance from the end-plate zone and decreases with Increased Fiber diameter and/or with Increased Fiber density. The quantitative relationship between these factors has been derived. Conclusions : The relationships determine the structural conditions in which irregular potential may be generated and therefore may be helpful in the interpretation of atypical MUPs.
Ewa Zalewska - One of the best experts on this subject based on the ideXlab platform.
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Atypical motor unit potentials in Emery-Dreifuss muscular dystrophy (EDMD).
Clinical Neurophysiology, 2005Co-Authors: K Rowińska-marcińska, Ewa Zalewska, Elzbieta Szmidt-salkowska, Anna Fidziańska, M. Dorobek, A. Karwańska, Irena Hausmanowa-petrusewiczAbstract:Abstract Objective The aim of the study was to analyse electromyographic changes in Emery–Dreifuss muscular dystrophy (EDMD) that are atypical for myopathy. Our special interest was focused on high amplitude polyphasic motor unit potentials (MUPs), also termed irregular MUPs. Methods We studied 21 EDMD patients with the diagnosis based on clinical data, DNA analysis and immunohistochemical muscle studies. Rectus femoris muscle biopsies were investigated in all affected patients. Electrophysiological investigations involved quantitative concentric needle electromyography (CNEMG) of biceps brachii (BB) and rectus femoris (RF) muscles. Simulation studies were performed to approximate the number, diameter and distribution of muscle Fibers, which contribute to irregular MUPs. Results The EMG data in EDMD were compatible with myopathy. Irregular MUPs showed longer duration, larger area, size index and higher amplitude then simple ones ( P 55μm) diameters than normal (50±5μm). Muscle biopsy specimens revealed the variable muscle Fiber size due to atrophy, hypertrophy, and muscle Fiber splitting. Conclusions Irregular MUPs recorded in EDMD are due to hypertrophied and atrophied Fibers as well as Increased Fiber density. They reflect reorganization of the motor unit in a slow progression myopathic process (muscle Fiber hypertrophy and splitting). Significance Irregular MUPs in EDMD most probably reflect Increased variability of the muscle Fiber size.
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Modeling studies on irregular motor unit potentials.
Clinical Neurophysiology, 2004Co-Authors: Ewa Zalewska, Irena Hausmanowa-petrusewicz, Erik StålbergAbstract:Abstract Objective : The aim of these modeling studies on the generation of motor unit potentials (MUPs) was to establish the influence of MU parameters and recording conditions on the shape irregularity of MUPs. The focus was on the dependence of the irregularity of MUPs on Fiber density, Fiber diameters and the recording distance from the end-plate zone. Methods : The study was performed using the ‘EMG Simulator’ software for modeling of MUP and our own software for calculations. Results : The results indicate that the irregularity of a MUP increases with Increased recording distance from the end-plate zone and decreases with Increased Fiber diameter and/or with Increased Fiber density. The quantitative relationship between these factors has been derived. Conclusions : The relationships determine the structural conditions in which irregular potential may be generated and therefore may be helpful in the interpretation of atypical MUPs.
