Deformation of Alumina/Titanium Carbide Composite at Elevated Temperatures

The deformation behavior of an Al₂O₃/30 wt% TIC composite in uniaxial tension was evaluated under vacuum over the temperature range of 1300° to 1550°C. The Al₂0₃/TiC composite exhibited the maximum elongation of 66% at an initial strain rate of 1.19 X l0^-4 s^-1 at 1550°C. The stress exponent calculated from peak stresses of true stress-true strain curves at 1500^OC was 3.8, which was in good agreement with that obtained by changing the crosshead speed during the tension test. The apparent activation energy at 20 MPa was 853 kJ/mol. In addition the deformation of the Al₂O³/TiC composite in uniaxial tension at elevated temperature was accompanied by cavitation.     

Crystalline Phases and YAG Laser-Induced Crystallization in Sm2O3–Bi2O3–B2O3 Glasses

The glass formation region, crystalline phases, second harmonic (SH) generation, and Nd:yttrium aluminum garnet (YAG) laser-induced crystallization in the Sm₂O₃–Bi₂O₃–B₂O₃ system were clarified. The crystalline phases of Bi₄B₂O₉, Bi₃B₅O₁₂, BiBO₃, Sm _x Bi_{1− x} BO₃, and SmB₃O₆ were formed through the usual crystallization in an electric furnace. The crystallized glasses consisting of BiBO₃ and Sm _x Bi_{1− x} BO₃ showed SH generations. The formation of the nonlinear optical BiB₃O₆ phase was not confirmed. The formation (writing) region of crystal lines consisting of Sm _x Bi_{1− x} BO₃ by YAG laser irradiation was determined, in which Sm₂O₃ contents were∼10 mol%. The present study demonstrates that Sm₂O₃–Bi₂O₃–B₂O₃ glasses are promising materials for optical functional applications.     

Reaction and diffusion of reactive disperse dye in nylon 6

The diffusion of a reactive disperse dye with a vinylsulfonyl group accompanied by simultaneous reaction with the amino end groups in nylon 6 was examined by the method of cylindrical film roll at 70°C and pH 2.2–8.0. The experimental diffusion profiles of the active and fixed species of the dye in nylon 6 were confirmed to be described by the diffusion equation accompanied by the chemical reaction with substrate taking the limited amount of the end groups into account, where the active species of dye were assumed to react only with the free base of amino end groups. The completion of the reaction with the amino end groups was observed in the first layer from the surface at pH 6.0–8.0. The value of diffusion coefficient was constant (8.0 × 10^?10 cm²/s) at all the pH's. The product of the second-order rate constant, k₂, of reaction of the dye and the dissociation constant, K_a, of the amino end groups was constant (k₂K_a = 4.0 × 10^?9 s^?1) at pH 2.2–8.0. The k₂ values of the reaction with various substrates for vinylsulfonyl and monochlorotriazinyl-reactive dyes were compared and the practical dyeing conditions were discussed.     

Preparation of ultrafine polyurethane fiber web by laser‐electrospinning combined with air blowing

Thermoplastic polyurethane fiber webs were prepared using a laser‐heated electrospinning process combined with air blowing. The effect of spinning conditions such as air flow rate and air temperature on fiber diameter and molecular weight was investigated. Although the average fiber diameter decreased with increased air flow rate at each air temperature, the diameter increased when the air flow rate was >15 NL min^?1. In addition, the fiber was comparatively thicker with an increase in the air temperature. The variation in the fiber diameter tends to increase with the air flow rate, and a reduction in the molecular weight of the fiber by thermal degradation was suppressed. The thinnest and most uniform fiber with a diameter of 0.9 µm and a diameter coefficient variation of 15% was obtained at an air temperature of 25°C under an air flow rate of 15 NL min^?1. This fiber also had a minimum of decreased molecular weight. POLYM. ENG. SCI., 54:2605–2609, 2014. © 2013 Society of Plastics Engineers     

Terpendole E and its Derivative Inhibit STLC‐ and GSK‐1‐Resistant Eg5

Terpendole E is first natural product found to inhibit mitotic kinesin Eg5, but its inhibitory mechanism remains to be revealed. Here, we report the effects of terpendole E and 11ketopaspaline (a new natural terpendole E analogue) on the Eg5–microtubule interaction and in several Eg5 mutants. 11‐Ketopaspaline is a shunt product from terpendole E, and it shows potent inhibitory activity against the microtubule‐stimulated ATPase activity of Eg5. Unlike other Eg5 inhibitors, such as S‐trityl‐L ‐cysteine (STLC) and GSK‐1, both terpendole E and 11‐ketopaspaline only partially inhibited Eg5–microtubule interaction. Furthermore, terpendole E and 11‐ketopaspaline inhibited several Eg5 mutants that are resistant to STLC (Eg5^D130A, Eg5^L214A) or GSK‐1 (Eg5^I299F, Eg5^A356T), but with the same extent of inhibition against wild‐type Eg5. Because Eg5^D130A and Eg5^L214A show cross‐resistance to most known Eg5 inhibitors, which bind the L5 loop, these results suggest that terpendole E and its analogues have a different binding site and/or inhibitory mechanism to those for L5 loop‐binding type Eg5 inhibitors.     

Effect of chitosan-gluconic acid conjugate/poly(vinyl alcohol) cryogels as wound dressing on partial-thickness wounds in diabetic rats

We previously developed chitosan cryogels from chitosan-gluconic acid conjugate without using toxic additives for wound care. In this study, we improved physiological characteristics of the previous cryogels by incorporating poly(vinyl alcohol) that also form cryogels. Mechanical strength of the cryogels was more than two times higher than that of the previous cryogels. Furthermore, the incorporation of poly(vinyl alcohol) enhanced water retention and resistance to degradation of the gels by lysozyme. The cryogels retained the favorable biological properties of the previous cryogels that they accelerate infiltration of inflammatory cells into wound sites. Time period for repairing 50 % of initial area of partial-thickness skin wound treated with the cryogels (4.0 ± 1.1 days) was shorter than those with gauze (6.5 ± 0.3 days) or a commercial hydrogel dressing (5.7 ± 0.3 days). Finally, we confirmed that incorporation of basic fibroblast growth factor into the cryogels was effective to further accelerate wound healing (2.7 ± 1.0 days). These results demonstrate that the cryogels in this study are promising for wound care.     

Te concentration dependent photoemission and inverse-photoemission study of FeSe1?xTex

We have characterized the electronic structure of FeSe_1−xTe_x for various x values using soft x-ray photoemission spectroscopy (SXPES), high-resolution photoemission spectroscopy (HRPES) and inverse photoemission spectroscopy (IPES). The SXPES valence band spectral shape shows that the 2 eV feature in FeSe, which was ascribed to the lower Hubbard band in previous theoretical studies, becomes less prominent with increasing x. HRPES exhibits systematic x dependence of the structure near the Fermi level (E_F): its splitting near E_F and filling of the pseudogap in FeSe. IPES shows two features, near E_F and approximately 6 eV above E_F; the former may be related to the Fe 3d states hybridized with chalcogenide p states, while the latter may consist of plane-wave-like and Se d components. In the incident electron energy dependence of IPES, the density of states near E_F for FeSe and FeTe has the Fano lineshape characteristic of resonant behavior. These compounds exhibit different resonance profiles, which may reflect the differences in their electronic structures. By combining the PES and IPES data the on-site Coulomb energy was estimated at 3.5 eV for FeSe.     

Terrain classification and identification of tree stems using ground‐based LiDAR

To operate autonomously in forested terrain, unmanned ground vehicles must be able to identify the load‐bearing surface of the terrain (i.e., the ground) and obstacles in the environment. To travel long distances, they must be able to track their position even when the forest canopy obstructs GPS signals, e.g., by tracking progress relative to tree stems. This paper presents a novel, robust approach for modeling the ground plane and tree stems in forests from a single viewpoint using a lightweight LiDAR scanner. Ground plane identification is implemented using a two‐stage approach. The first stage, a local height‐based filter, discards most nonground points. The second stage, based on a support vector machine classifier, identifies which of the remaining points belong to the ground. Main tree stems are modeled as cylinders or cones to estimate the diameter 130 cm above the ground plane. To fit these models, candidate main stem data are selected by finding points approximately 130 cm above the ground. These points are clustered into separate point clouds for each stem. Cylinders and cones are fit to each point cloud, and heuristic filters identify which fits correspond to tree stems. Experimental results from five forested environments demonstrate the effectiveness of this approach. For ground plane estimation, the overall classification accuracy was 86.28% with a mean error for the ground height of approximately 4.7 cm. For stem estimation, up to 50% of the main stems were accurately modeled using cones, with a root mean square diameter error of 13.2 cm.© 2012 Wiley Periodicals, Inc.     

Abstract picture generation and zooming user interface for intuitive music browsing

Today many people store music media files in personal computers or portable audio players, thanks to recent evolution of multimedia technologies. The more music media files these devices store, the messier it is to search for tunes that users want to listen to. We propose MusCat, a music browser to interactively search for the tunes according to features, not according to metadata (e.g. title, artist name). The technique firstly calculates features of tunes, and then hierarchically clusters the tunes according to the features. It then automatically generates abstract pictures, so that users can recognize characteristics of tunes more instantly and intuitionally. It finally visualizes the tunes by using abstract pictures. MusCat enables intuitive music selection with the zooming user interface.     

Investigation of Precipitation Behavior in Age-Hardenable Cu-Ti Alloys by an Extraction-Based Approach

We investigated the precipitation processes in Cu-4 mol pct Ti alloy specimens aged at 723 K (450 °C), by means of X-ray diffraction and chemical analyses of the precipitates extracted from the parent alloy specimens. Aging-induced precipitate particles of a spinodally decomposed disorder, α′; those of a metastable order, β′-Cu₄Ti; and those of a stable order, β-Cu₄Ti, were continuously formed in the aged specimens. The extraction of the precipitate particles from the aged specimens by submergence in a nitric solution allowed for not only the structural analyses of the constituent precipitate phases but also the quantitative evaluation of their chemical compositions and volume fractions. Early during the aging process, the supersaturated Cu solid solution decomposes spinodally in a continuous manner, and an unstable disorder, α′, appears. Then, fine needle-shaped β′-Cu₄Ti particles, which have a Ti content of approximately 37.5 mol pct, form in the Cu matrix. During prolonged aging, coarse cellular components composed of the terminal Cu solid solution and stable β-Cu₄Ti particles which have a Ti content of 20.5 mol pct nucleate and grow, primarily in the grain boundaries, at the expense of the metastable β′-Cu₄Ti particles. The volume fraction of the β′-Cu₄Ti particles in the alloy reaches a maximum of approximately 1.7 pct after aging for 24 hours, while that of the β-Cu₄Ti particles increases steadily to more than 18 pct after 480 hours. The volume fraction of the fine β′-Cu₄Ti particles in the alloy specimens remained constant throughout the age-hardening, indicating that the hardening is primarily owing to the fine dispersion of the β′-Cu₄Ti particles and not because of the large volume fraction of coarse β-Cu₄Ti particles.