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To obtain uniform power distribution on the ATR prism for biomedical spectroscopy system, the power intensity mapping on the prism is precisely measured by using a newly developed probing technique. It is found that the distribution of QCL based system is less uniform than that of the FT-IR based system due to the high coherency of the laser beam. To homogenize the distribution, a lens is introduced to diffuse the light and the incident beam is inclined to increase the number of reflections in the prism. As a result, we confirmed that the measurement error of in-vivo experiments is suppressed.

Multi-directional measurement using multi-directional light sources and multi-directional photodetectors drastically increases the amount of observation data without increasing the number of optical probes. In this study, we developed a novel multi-directional functional near-infrared spectroscopy (fNIRS) system for human neuroimaging studies. We tested our system by measuring the cortical hemodynamic changes of a single subject during a motor task and compared them with the same subject's functional magnetic resonance imaging (fMRI) data. We detected the direction-dependent fNIRS signals that originate from the cortical hemodynamic changes that are consistent with the fMRI data.

A chemoselective synthesis of poly(o-hydroxy-amide) as a polybenzoxazolc precursor has been developed. The polycondensation was carried out by addition of isophthaloyl dichloride to a solution of 3,3'-dihydroxybenzidine and lithium chloride in N-methylpyrrolidinone and gave the selective N-acylated polymer, poly(o-hydroxy-amide) with an inherent viscosity of 0.7 dL g -1 . The structure of the polymer was characterized by IR, 1 H, and 1 3 C NMR spectroscopies. The model reaction was studied in detail to demonstrate the feasibility of the chemoselective polyamidation using benzoyl chloride and o-aminophenol.

We have carried out electronic structure and transport calculations for magnetic tunnel junctions (MTJ) composed of MgO and a half-metallic full Heusler alloy Co(2)MnSi on the basis of the density functional theory and the Landauer formula. We find that the density of states of Co atoms at the Co(2)MnSi/MgO(001) interface shifts toward the higher energy side due to the reduced symmetry, leading to a reduction of the spin polarization at the interface. Furthermore, we show that the majority-spin transmittance as a function of the in-plane wavevector [Formula: see text] has a broad peak centred at [Formula: see text] due to the tunnelling from the Δ(1) channel of Co(2)MnSi, while the transmittance from the Δ(5) channel is three orders of magnitude smaller than that of the Δ(1) channel. These results indicate that coherent tunnelling through the Δ(1) band is dominant also in an MTJ with Co(2)MnSi and an MgO barrier, like in Fe/MgO/Fe(001) MTJ and related systems.

Poly (3-phenyl-2,5-thiophene) with inherent viscosities up to 0.50 dl-g −1 was obtained under mild conditions. The effects of various factors, such as amount of catalyst and ligand, reaction medium, and reaction temperature, were studied. 13 C NMR spectroscopy showed that the polymer obtained had the expected structure without mislinkage through the β-position and the random structure on regiospecificity. The polymer was readily soluble in common organic solvents and can be processed into uniform films from their solution. The thermogravimetry of the polymer showed 10% weight loss at 550 and 570°C in air and in nitrogen, respectively

We present first-principles based calculations of electronic structures and tunneling conductance of ${\text{Co}}_{2}YZ/\text{MgO}(\ensuremath{\sim}2\text{ }\text{nm})/{\text{Co}}_{2}YZ(001)$ $(YZ=\text{MnSi},\text{CrAl})$ magnetic tunnel junctions (MTJs). It is found that $YZ$(MnSi and CrAl)-terminated interfaces are thermodynamically stable as compared with Co-terminated interfaces in ${\text{Co}}_{2}YZ/\text{MgO}(001)$ junctions. In the CrAl-termination, no interface states appear in both sides of the junctions, preserving the half metallicity of ${\text{Co}}_{2}\text{CrAl}$, while reduction of the spin polarization is significant in the MnSi termination. ${\text{Co}}_{2}\text{CrAl}$, however, has no ${\ensuremath{\Delta}}_{1}$ band at the Fermi level, thus the majority-spin conductance of ${\text{Co}}_{2}\text{CrAl}/\text{MgO}/{\text{Co}}_{2}\text{CrAl}(001)$ MTJs in the parallel magnetization is much smaller than that of ${\text{Co}}_{2}\text{MnSi}/\text{MgO}/{\text{Co}}_{2}\text{MnSi}(001)$ MTJs. We propose that MTJs having an ultrathin ${\text{Co}}_{2}\text{CrAl}$ layer between ${\text{Co}}_{2}\text{MnSi}$ electrode and MgO barrier, i.e., ${\text{Co}}_{2}\text{MnSi}/{\text{Co}}_{2}\text{CrAl}/\text{MgO}(001)$ junctions, can derive both the half-metallic character at the interface and the large tunneling conductance through the ${\ensuremath{\Delta}}_{1}$ channel in the parallel magnetization.