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61.
Koki Murano Tomoyoshi Shimobaba Atsushi Sugiyama Naoki Takada Takashi Kakue Minoru Oikawa Tomoyoshi Ito 《Computer Physics Communications》2014
We report fast computation of computer-generated holograms (CGHs) using Xeon Phi coprocessors, which have massively x86-based processors on one chip, recently released by Intel. CGHs can generate arbitrary light wavefronts, and therefore, are promising technology for many applications: for example, three-dimensional displays, diffractive optical elements, and the generation of arbitrary beams. CGHs incur enormous computational cost. In this paper, we describe the implementations of several CGH generating algorithms on the Xeon Phi, and the comparisons in terms of the performance and the ease of programming between the Xeon Phi, a CPU and graphics processing unit (GPU). 相似文献
62.
Takashi Mitamura Hiroyuki Ogino Hidehiko Kobayashi Toshiyuki Mori Hiroshi Yamamura 《Journal of the American Ceramic Society》1993,76(8):2127-2128
Preparation of BaLa2 O4 , Ba3 ,Y4 O9 , Ba ,In2 O5 , and Ba3 Ga2 O6 powders and their sintering were investigated in Ar or air. These sintered bodies with perovskite-related structure were synthesized by reaction sintering, using mixed powders in the atomic ratios of Ba/La = 1, Ba/Y = 0.75, Ba/In = 1, and Ba/Ga = 1.5. The order-disorder transition temperatures of the BaLa2 O4 , Ba3 Y4 O9 , Ba2 In2 O5 , and Ba3 Ga2 O6 sintered bodies were 270°, 350°, 880°, and 123Oo C, respectively. It was found that the temperatures were influenced by the ionic radius of cations in B sites, and the transition temperatures decreased with increasing ionic radius. 相似文献
63.
Uniaxial drawing experiments of the polystyrene films plasticized by a sorption of compressed CO2 gas at pressures up to about 18 MPa were carried out with strain rates ε of 0.0290 and 0.0079 s?1. The drawing was performed successfully with draw ratio λ up to 4 at the temperatures of 308.15, 318.15, 328.15, and 338.15 K. The Hermans orientation function f of the drawn samples was determined from the dichroic ratio measured by an infrared spectrophotmeter. While f value increases with increasing ε or λ, it decreases with increasing CO2 pressure or temperature. © 1995 John Wiley & Sons, Inc. 相似文献
64.
Annadanam V. Sesha Sainath Takashi Inoue Yoshiharu Hatakeyama Masahiro Shishido Kenzo Okamoto Seigou Kawaguchi Takashi Kuriyama Kiyohito Koyama 《大分子材料与工程》2004,289(3):264-268
Summary: Polyacrylonitrile (PAN) particles with micro‐size ranges (0.15–2 μm) were prepared by emulsion and dispersion polymerizationa and in supercritical carbon dioxide media. The PAN particles were blended with Nylon 6 (PA6) at 220 °C by using a miniature mixer; it was found that melt‐mixing was possible for PAN‐rich compositions as high as 70 wt.‐%. Blends were characterized by scanning electron microscopy, IR, viscosity measurements, differential scanning calorimetry, and dynamic mechanical thermal analysis (DMTA). The size and shape of original PAN particles were retained in PAN/PA6 blends. The useful range to blend PAN particles size was less than 1 μm in terms of shape retention of the PAN particles in blends. Blends with 40 wt.‐% PAN content were found to be melt‐processable. The elastic modulus was higher for PAN/PA6 blends than pure PA6.
65.
Katsuhiko Ariga Takashi Nakanishi Yukiko Terasaka Jun-ichi Kikuchi 《Journal of Porous Materials》2006,13(3):427-430
As a soft and flexible porous structure, a pore array of a steroid cyclophane SC(OH), which consists of the rigid 1,6,20,25-tetraaza[6.1.6.1]paracyclophane
ring connected to four steroid moieties (cholic acid) through flexible L-lysine spacers, was prepared at the air-water interface.
As confirmed by surface pressure (π)-molecular area (A) isotherms, transition between open conformation and cavity conformation
of the SC(OH) molecule was reversibly induced upon repeated compression and expansion of its monolayer at pH 11 where amino
groups of the lysine residues are not fully deprotonated. Capture and release of an aqueous fluorescent guest (TNS) by SC(OH)
was observed upon dynamic cavity formation through surface fluorescence spectroscopy. At pH 12, dynamic cavity formation of
SC(OH) was sufficiently suppressed, and the capture and release of an aqueous TNS by the monolayer was not virtually observed.
Lessened electrostatic repulsion between the SC(OH) molecules due to conversion of ammonium to free amine may prevent the
cavity from reopening. The importance of dynamic nature of cavity formation on the guest binding was also proved by control
experiments using SC(H), which cannot form cavity conformation at any surface pressures at both pH 11 and 12. 相似文献
66.
Takeo Tokiai Takashi Uesugi Kunihito Koumoto 《Journal of the American Ceramic Society》1995,78(4):1089-1092
High thermoelectric figure of merit semiconducting ceramics of n -type iron disilicide with modified local compositions have been developed. Sintering and annealing of the composite powder composed of iron disilicide and precipitated cobalt (II) hydroxide resulted in the dissolution of excess Co and oxygen into the iron disilicide phase. Excess Co segregated to the grain boundary region, while interstitially incorporated oxygen was distributed homogeneously in the microstructure. The maximum figure of merit achieved was 5.2 × 10−4 /K at 673 K. 相似文献
67.
Effects of hydrostatic extrusion on the thermal properties of polycarbonate (PC) and of high-impact polystyrene (HIPS) were studied using differential scanning calorimeter (DSC) measurements. A glass transition temperature (Tg) and a peak temperature were determined from the DSC curves for both PC and HIPS extrudates. The Tg values of the PC extrudates, with a percentage reduction in area, R, from 40 to 50%, change appreciably from the value for the as–received PC. The results of the hydrostatic extrusion of the PC billets suggest that a two stage deformation process of molecular chains may be involved. Shear-banding is observed for HIPS extrudates with R = 30 to 60%; this fact indicates that a sub-glass transition (β-transition) occurs at temperatures below Tg. It is suggested that the molecular chains of the HIPS extrudate with R = 70% are oriented in the direction of hydrostatic extrusion. The deformation mechanism of molecular chains caused by the hydrostatic extrusion is discussed. 相似文献
68.
Takashi Hayakawa Hideo Orita Masao Shimizu Katsuomi Takehira Arnfinn G. Andersen Kiyoshi Nomura Yusuke Ujihira 《Catalysis Letters》1992,16(4):359-371
The catalytic activity of LaCoO3–-based mixed oxides for the oxidative coupling of methane has been tested by TPR and cyclic reaction. Characterization has been done by XRD, TGA and Mössbauer spectrometry. It is likely that the perovskite-crystal structure containing hypervalent metal ions has an important role and that unique structural oxygen species in the perovskite contribute to the partial oxidation of methane. 相似文献
69.
Ken Shimomai Noboru Higashida Toshiaki Ougizawa Takashi Inoue Bernd Rudolf Jörg Kressler 《Polymer》1996,37(26):5877-5882
The miscibility of poly(methyl methacrylate) (PMMA) and styrene-acrylonitrile random copolymers (SAN) blends was investigated on the basis of the Flory—Orwoll—Vrij equation of state theory. To obtain the equation of state parameters (P*, V*sp, T*: characteristic parameters), the pressure—volume—temperature (PVT) behaviour was measured for PMMA and a series of SANs with various acrylonitrile contents. The exchange energy parameter Xij was also calculated by fitting the theory to some phase diagrams of PMMA/SAN blends. The Flory—Huggins interaction parameter χ was separated into two contributions based on the equation of state theory for mixtures: the exchange energy term χinter and the free volume term χfree. Both the temperature and copolymer composition dependences of χinter and χfree were estimated by calculations using the equation of state parameters. There exists a region in which χinter is negative, leading to a miscibility window in PMMA/SAN blends. However, the immiscibility at high temperatures in the blends cannot be explained only by χinter; it is caused by the free volume contribution, χfree. The miscibility window behaviour in PMMA/SAN blends may be explained within the framework of the equation of state theory. 相似文献
70.
The change in morphology and interface quantities have been analyzed for an immiscible polymer blend during reactive processing. A model polymer/polymer combination, hydroxy-terminated poly(ε-caprolactone)/liquid rubber with α, ω-carboxy groups, was employed. The blend was subjected to light scattering measurements, ellipsometry, and gel permeation chromatography (GPC). Size reduction of the dispersed phase during processing was followed by a systematic decrease in the correlation distance ζ and an increase in the specific interfacial area Ssp, both by the Debye-Bueche plot of light scattering profiles. Also observed was the time variation of the volume fraction of interface Vλ estimated as a product of the Ssp and the interfacial thickness by ellipsometry. The changes in ζ, Ssp, and Vλ with processing were accelerated when a coupling agent,γ-aminopropyltriethoxysilane (APS), was added. The amount of block copolymer formed in-situ in the APS-loaded system was estimated by GPC with RI and UV detectors. For the size reduction kinetics in both APS-loaded and -unloaded systems, Rittinger's law was found to be applicable. 相似文献