A novel surfactant of N–dodecanoyl–N–(2-hydroxyethyl)–β–alanine (coded as C12–EtOH–βAla) was synthesized by modifying the methyl group of N–dodecanoyl–N–methyl–β–alanine (coded as C12–Me–βAla). Amino-acid-type surfactants (C12–EtOH–βAla and C12–Me–βAla) are more healthy and environmentally friendly compared to sodium dodecyl sulfate (SDS). To investigate the microstructures of these new surfactants, we employed a method of time-of-flight small-angle neutron scattering (TOF SANS) at a pulsed neutron source, Tokai Japan (J–PARC). The advances in TOF SANS enable simultaneous multiscale observations without changing the detector positions, which is usually necessary for SANS at the reactor or small-angle X-ray scattering. We performed in situ and real-time observations of microstructures of collapsing shampoo foam covering over a wide range of length scales from 100 to 0.1 nm. After starting an air pump, we obtained time-resolved SANS from smaller wave number, small-angle scattering attributed to (1) a single bimolecular layer with a disk shape, (2) micelles in a bimolecular layer, and (3) incoherent scattering due to the hydrogen atoms of surfactants. The micelle in the foam film was the same size as the micelle found in the solution before foaming. The film thickness (~27 nm) was stable for a long time (<3600 s), and we simultaneously found a Newton black film of 6 nm thickness at a long time limit (~1000 s). The incoherent scattering obtained with different contrasts using protonated and deuterated water was crucial to determining the water content in the foam film, which was about 10~5 wt%.
The purpose of this study was to clarify the development of principal motor movements controlling ball-kicking performance by comparing skilled soccer players with unskilled counterparts. Fifty-three skilled and sixty unskilled male college students, aged 18 to 22, were asked to perform ball-kicking as far as possible within a 30-degree fan-shaped area. The ball-kicking consisting of various movement elements was video-taped by two Hi-8 video cameras. A new version of Cause and Effect Diagram was developed to clarify a structure of ball-kicking movement qualitatively. Delphi method was applied to determine content validity of the ball-kicking movements. The ball-kicking movements in the motor process were measured by 28 movement items. Multiple regression analysis with stepwise procedure was utilized to determine criterion-related validity with various principal motor movements as the independent variables and maximum performance in ball-kicking as the dependent variable. The multiple correlation coefficient was 0.88 for the skilled player group, and 0.71 for the unskilled player group. The number of principal motor movements extracted was 9 for the skilled player group, and 6 for the unskilled. The most contributing principal movement to ball-kicking performance was inside inclination of the supporting leg in the forward-swing phase (27%) for the skilled player group, and inclination of legs in the approaching phase (46%) for the unskilled. The results indicate that the principal motor movements controlling ball-kicking performance develop corresponding to improvement in ball-kicking skill.
Neutron diffraction measurements under high magnetic fields have been performed for the multiferroic compound HoMn$_{2}$O$_{5}$. At zero field, high-temperature incommensurate magnetic (HT-ICM) -- commensurate magnetic (CM) -- low-temperature incommensurate magnetic (LT-ICM) orders occur with decreasing temperature, where ferroelectric polarization arises only in the CM phase. Upon applying a magnetic field, the LT-ICM phase completely disappears and the CM phase is induced at the lowest temperature. This field-induced CM state is completely associated with the field-induced electric polarization in this material [Higashiyama {\it et al}., Phys. Rev. B {\bf 72}, 064421 (2005).], strongly indicating that the commensurate spin state is essential to the ferroelectricity in the multiferroic $R$Mn$_{2}$O$_{5}$ system.
PrBaInO x (PBI) and materials with related structures of perovskite were added to the anode of Solid Oxide Fuel Cells (SOFCs). The electrochemical performance of SOFCs improved by addition of PBI particles to the Ni/GDC anode in dry methane fuel. The effect of added PBI and materials with related structures of perovskite on the electrode characteristics was then investigated to determine the appropriate SOFC anode additive. Electrochemical measurements of Ni/GDC anodes with added PBI, PrInO 3 , BaCeO 3 and Gd-doped BaCeO 3 (BCG) suggest that BCG is the most effective anode additive for dry methane fuel. With wet H 2 (1% H 2 O) fuel, the addition of BCG improved the electrochemical performance only of the Ni-free GDC anode, possibly due to the difference in hydrogen dissociative adsorption performance with and without Ni.
Precisely controlling BaO activity and improving the compositional homogeneity of BZY20 suppress effectively formation of second phases of BaY2NiO5 and Y2O3.
Here we show the first observation of an unusual intermolecular magnetic interaction in the liquid-crystalline (LC) state of an all-organic radical compound at 73 °C on water; the magnetic interaction actually allows the LC droplet on water to be attracted by a weak permanent magnet, whereas the crystalline phase did not respond to the magnet.
We carried out time-resolved small-angle neutron scattering (SANS) and ultrasmall-angle neutron scattering (USANS) studies of dynamically polarized high-density polyethylene (HDPE) doped with 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) persistent free radicals. We observed a remarkable enhancement of the scattering intensity shortly after a switching of microwave frequency from positive (negative) to negative (positive) dynamic nuclear polarization (DNP). The enhancement was found to be due to spatially heterogeneous proton-spin polarization generated as a result of heterogeneously distributed TEMPO in the HDPE sample. The spatial fluctuation of the polarization ranged up to the length-scale of ≥100 nm. This result strongly suggests that the TEMPO free radicals are localized more in nonfibrils but less in fibrils of HDPE. In this way, we propose that the time-resolved DNP-SANS and DNP-USANS be general techniques to determine mesoscale spatial distribution of electron spins in dielectric materials.
The partial scattering function (PSF) analysis through contrast variation small-angle neutron scattering experiments is applied to characterize structures of anion-exchange membranes (AEMs), prepared by graft copolymerization of 2-methyl-N-vinylimidazolium (Im) and styrene (St) monomers with Im/St ratios of 62/38 and 26/74 (denoted as AEM_IS64 and AEM_IS37, respectively), on a poly(ethylene-co-tetrafluoroethylene) base polymer (BP). The PSF self-terms can be expressed by the combination of mass fractal, Teubner–Strey, Guinier exponential, and hard-sphere structural models to give exact structural information such as shape and size of individual domains of hydrophobic BP, hydrophilic graft-polymer (GP), and water (W). For AEM_IS64, the hydrophilic ion channels (GP/W domains) show bicontinuous and spherical structures with mean separation distances of 33–34 nm and a radius of 4.0 nm, respectively. This result suggests a new structural feature of the coexistence of bicontinuous and isolated GP/W spheres. Furthermore, in a low q-region, a slightly larger fractal dimension for GP (∼1.7) than those of BP and W (∼1.1) strongly supports the previously proposed "conducting and nonconducting two-phase structure" because only GP distributes in both phases. In AEM_IS37, GP/W and BP domains show an ion channel network structure with random particles having an average radius of gyration of 10.0 nm, and hard-sphere model fitting in the high-q region confirms previously proposed "waterpuddle" structure with 3.8 nm diameter. PSF analysis in this work visualized the entire hierarchical structure of individual components in graft-type AEMs, providing mechanistic insights into the effects of functional GPs on phase-separation and ion channel structures.
