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Characterization of anisotropic conductivity of thin carbon fiber/poly ether ether ketone (PEEK) composite was investigated by noncontact and nondestructive microwave probe pumping (MPP) technique. The microwave was pumped by a coaxial probe, and the pumped field intensity distribution was measured by a near-field scanning microwave microprobe (NSMM) and a thermography camera. From the measurement and simulation results, it was observed that intensity of the electromagnetic field was higher along the high conductive directions due to the larger eddy current along these directions. Additionally, electrical defect detection by pumping probe technique was investigated. It was observed that the field intensity drastically decreased around the electrical defect. We showed that through an anisotropic field distribution around the pumping probe, an electrical defect of a carbon fiber/PEEK composite can be detected by combination of MPP and NSMM techniques. [ABSTRACT FROM AUTHOR]

We study the opto-electrical properties of Natronomonas pharaonis sensory rhodopsin II (NpSRII) by using a near-field microwave microprobe (NFMM) under external light illumination. To investigate the possibility of application of NFMM to biological macromolecules, we used time dependent properties of NPSRII before/after light activation which has three distinct states - ground-state, M-state, and O-state. The diagnostic ability of NFMM is demonstrated by measuring the microwave reflection coefficient ( S11) spectrum of NpSRII under steady-state illumination in the wavelength range of 350-650 nm. Moreover, we present microwave reflection coefficient S11 spectra in the same wavelength range for two fast-photocycling rhodopsins: green light-absorbing proteorhodopsin (GPR) and Gloeobacter rhodopsin (GR). In addition the frequency sweep shift can be detected completely even for tiny amounts of sample (∼10-3 OD of rhodopsin). Based on these results NFMM shows both very high sensitivity for detecting conformational changes and produces a good time-resolved spectrum. (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Abstract: The crystallization process of bismuth substituted yttrium iron garnet (Bi x Y3−x Fe5O12; x =0, 1, 2) powder prepared by the metal-organic decomposition method has been studied with various sintering temperatures. The pure garnet phase was observed for the x =1 powder at 900°C sintering temperature, whereas the x =0, 2 powder showed secondary phases. The x =0 powder showed a similar crystallization process to that of the solid state reaction method. For the x =1, 2 powders, it is proposed that the lowering of the crystallization temperature is due to the lowered stability of the intermediate phase. The infrared spectroscopy and magnetic properties were also investigated. The pure garnet phase showed three absorption bands located at 563, 598, 655cm−1 that shifted to 555, 588, 639cm−1 along with an increase of bismuth concentration. The maximum values of saturation and remanence magnetization and the minimum value of coercivity were observed for the x =1 powder sintered at 900°C, which were 20.8emu/g, 2.67emu/g, and 31.9Oe, respectively. [Copyright &y& Elsevier]