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The electrical and thermoelectric properties of an organic elastomer composite composed of carbon nanotubes (CNTs) and a nonconductive polymer were systemically investigated as a function of CNT content. As the CNT content of the poly(dimethylsiloxane) (PDMS) matrix increased, the electrical conductivity increased remarkably (by about 250 times) without a large increase in the thermal conductivity, which could lead to significant improvement in the ZT value. Moreover, the Seebeck coefficient was also enhanced by increasing the CNT content. Consequently, the ZT value was effectively increased by a small increase in the quantity of CNTs in the nonconductive polymer matrix.

The Charpy impact test is used to identify the transition between ductility and brittleness. The percentages of ductile and brittle fractures in steel can be evaluated based on each fracture area, which is presently determined by an analyzer with the naked eye. This method may lead to subjective judgement, and difficulty accurately quantifying the percentage. To resolve this problem, a new analysis method based on image processing is proposed in this study. A program that can automatically calculate the percentage of the ductile and brittle fractures has been developed. The analysis is performed after converting an RGB fracture image into a binary image using image processing techniques. The final binary image consists of 0 and 1 pixels. The parts with the pixel values of 1 correspond to the brittle fracture areas, and the pixel values of 0 represent the ductile fracture areas. As a result, by counting the number of 0 pixels in the entire area, it is possible to automatically calculate the percentage of ductile fracture. Using the proposed automatic fracture analysis program, it is possible to selectively distinguish only the brittle fracture from the entire fracture area, and to accurately and quantitatively calculate the percentages of ductile and brittle fractures.

This paper presents the application of polypyrrole(PPy) as a medium material for the release and the detection of a neurotransmitter, i.e. epinephrine, using its electrically stimulated ion exchange property. Neuron signals are transmitted in a synapse, which is composed of releasing and detecting parts of neurotransmitters. PPy was electrochemically polymerized with NaDBS as dopants on Au electrode and then was incorporated with epinephrine by cation exchange process. The incorporated epinephrine was released by applying a controlled voltage and the released amount of epinephrine was determined using an ultraviolet(UV) spectrometry. Experimental results of the releasing part show that the released amount of epinephrine dependeds not only on the thickness and the size of PPy film but also on the releasing time. Spontaneously diffused epinephrine amount was measured to be only 18% of the voltage driven release amount. The absorbance change of epinephrine due to the applied potential during releasing process is negligible compared with that of the released epinephrine. Overoxidized PPy(OxPPy) for the detecting part shows a good cation permselectivity for the detection of epinephrine and the current is also higher than that at the Au electrode in the same concentration of the epinephrine. The current level is different with dopants with which the OxPPy film is polymerized and the sensitivity of the OxPPy electrode depends on the thickness of PPy film.