Development of a high‐resolution RGBW flexible display using a white organic light‐emitting diode with microcavity structure and that of a side‐roll touch panel

In this study, white organic electroluminescent devices with microcavity structures were developed. A flexible high‐resolution active‐matrix organic light‐emitting diode display with low power consumption using red, green, blue, and white sub‐pixels formed by a color‐filter method was fabricated. In addition, a side‐roll touch display was developed in combination with a capacitive flexible touch screen.     

Formation, Characterization, and Hot Isostatic Pressing of Cr2O3-Doped ZrO2 (0,3 mol% Y2O3) Prepared by Hydrazine Method

In the ZrO₂-Cr₂O₃ system, metastable t -ZrO₂ solid solutions containing up to 11 mol% Cr₂O₃ crystallize at low temperatures from amorphous materials prepared by the hydrazine method. The lattice parameter c decreases linearly from 0.5149 to 0.5077 nm with increased Cr₂O₃ content, whereas the lattice parameter a is a constant value ( a = 0.5077 nm) regardless of the starting composition. At higher temperatures, transformation (decomposition) of the solid solutions proceeds in the following way: t (ss)→ t (ss) + m + Cr₂O₃→ m + Cr₂O₃. Above 11 mol% Cr₂O₃ addition, c-ZrO₂ phases are formed in the presence of Cr₂O₃. The t -ZrO₂ solid solution powders have been characterized for particle size, shape, and surface area. They consist of very fine particles (15–30 nm) showing thin platelike morphology. Dense ZrO₂(3Y)-Cr₂O₃ composite ceramics (∼99.7% of theoretical) with an average grain size of 0.3 μm have been fabricated by hot isostatic pressing for 2 h at 1400°C and 196 MPa. Their fracture toughness increases with increased Cr₂O₃ content. The highest K _Ic value of 9.5 MPa·;m^1/2 is achieved in the composite ceramics containing 10 mol% Cr₂O₃.     

Radiation-induced polymerization of ethylene in pilot plant. III. Heavy-phase recycling process

Radiation-induced polymerization of ethylene using aqueous tert-butyl alcohol as medium was carried out in a large-scale pilot plant with a 50-liter central source-type reactor at a pressure of 105 to 395 kg/cm², temperature of 30° to 80°C, mean dose rate of 4.5 × 10⁴ to 1.9 × 10⁵ rads/hr, ethylene feed rate of 5.5 to 23.5 kg/hr, and medium feed rate of 21 to 102 l./hr. The space–time yield and molecular weight of the polymer were in the range of 4.7 to 16.8 g/l.-hr and 1.3 × 10⁴ to 8.9 × 10⁴, respectively. The space–time yield and molecular weight increased with mean residence time at 30°C, whereas at 80°C they became almost independent of the time. The space–time yield increased with pressure and dose rate, slightly decreased with temperature, and was maximum at ethylene molar fraction of 0.5. The polymer molecular weight increased with pressure and ethylene molar fraction, and decreased with dose rate and temperature. The total amount of deposited polymer on the reactor wall, source case wall, and scraping blades was usually less than 1 kg, which was negligibly small for the analysis of polymerization. Continuous discharge of the polymer slurry and production of fine-powder polyethylene were successfully carried out. In the central source-type reactor, a dose rate of 1.9 × 10⁵ rads/hr was obtained with a ⁶⁰Co source of ca. 12 kCi.     

Application of the Solvothermal Process in the Synthesis of High-performance Ag/γ-Al_2O_3 Catalysts

1 INTRODUCTION Since Cu-ZSM-5 was reported as an effective catalyst for the selective catalytic reduction (SCR) of NO by hydrocarbons in the presence of excess oxygen, the SCR of NOx has received much attention as a kind of potential technology for cleaning NOx in various oxygen-rich exhausts of diesel engine, lean burning gasoline engine and gas engine. Although a number of catalysts have been tested, to date, it still seems to be difficult to find a catalyst that is completely suit…     

Highly anisotropic thermal conductivity of mesogenic epoxy resin film through orientation control

To develop insulating materials with a high thermally conductive anisotropy, planarly aligned mesogenic epoxy (ME) resin film was fabricated by uniaxial coating on a hydrophobic polyethylene terephthalate substrate. Grazing incidence small-angle X-ray scattering (GISAXS) and transmission SAXS measurements exhibited that the films spontaneously formed uniaxially aligned monodomain-like smectic structures by curing on the hydrophobic substrate. Then, an in- and out-of-plane thermal conductivity of 10 and 0.048 W m⁻¹ K⁻¹ and outstanding thermal conductivity anisotropy of 208 have been confirmed, respectively. The ME resin films with high thermal conductivity can be applied as insulating materials for multiple-layer electrical and electronic devices.     

Thermal stability of lamellar structure of PST crystal and lamellar boundary design for creep resistant TiAl alloy

The stability of lamellar structure is crucial for the creep resistance of TiAl alloys, but degradation of the lamellar structure is unavoidable at high temperatures. The degradation of the lamellar structure in PST crystals of Ti-48mol.%Al was studied during high temperature exposure (annealing and creep testing) to examine how to make a stable lamellar structure with high creep deformation resistance. Since the six orientation variants of γ lamellae are nucleated independently of the adjoining lamellae, pseudo twin and 120° rotational fault boundaries are most frequently observed at the initial stage of lamellar formation. The preferential removal of high energy (pseudo twin and 120° rotational fault) boundaries during the evolution of lamellar structure results in the highly probable appearance of a true twin boundary at a later stage of lamellar evolution. The coarsening of lamellar spacing and the spheroidization of the lamellae are the major degradation events occurring during creep deformation, and the migration of the lamellar boundaries brings both of them about. The lamellar structures of TiAl alloy contain four types of lamellar boundaries. The stability of the four types of boundaries decreases in the following order: γ/α₂ > true twin > pseudo twin > or=120° rotational fault boundaries. The γ/α₂ boundary has the highest stability (lowest mobility), and the high density of γ/α₂ boundaries is proposed to make a stable lamellar structure with good creep resistance. A material having the high density of γ/α₂ boundaries was produced through the heat treatment of a PST crystal in the α+γ two-phase regime. The excellent creep properties of the material were proven through creep tests of hard oriented PST crystals made of the material. This article is based on a presentation made in the 2002 Korea-US symposium on the “Phase Transformations of Nano-Materials,” organized as a special program of the 2002 Annual Meeting of the Korean Institute of Metals and Materials, held at Yonsei University, Seoul, Korea on October 25–26, 2002.     

Effects of blasting parameters on removability of residual grit

This article shows the quantitative evaluation of the residual grit on a blasted substrate, and the removability of the residual grit is examined. Carbon steel plates were blasted by white alumina grit with mean diameters of 338 to 1106 μm. The velocity and the number of grit particles were measured during blasting. The residual grit was removed from a substrate surface by the dissolution of the blasted substrate surface. A mixed acid solution was used as the dissolution solution. The residual grit weight was 7 to 17 g/m². The amount of the residual grit and the penetration depth of the embedded grit increased with increasing grit size. The penetration depth was 5 to 9% of the mean diameter of the grit. The residual grit weight and the penetration depth increased with the increase of the momentum of the grit particle. This article was originally published inBuilding on 100 Years of Success, Proceedings of the 2006 International Thermal Spray Conference (Seattle, WA), May 15–18, 2006, B.R. Marple, M.M. Hyland, Y.-Ch. Lau, R.S. Lima, and J. Voyer, Ed., ASM International, Materials Park, OH, 2006.     

Repeatedly foldable AMOLED display

In this study, a 5.9‐inch foldable active‐matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10^?6 g/m²?day or less, which improves OLED reliability. With these techniques, we have developed a book‐type display, which is repeatedly foldable like a book, and a tri‐fold display including a display area, which is foldable in three.     

The effects of amino-acid mutations on specific interactions between urokinase-type plasminogen activator and its receptor: Ab initio molecular orbital calculations

During cancer invasion, the binding of urokinase-type plasminogen activator (uPA) to its receptor (uPAR) on the surface of a cancer cell is considered a trigger for invasion. Here, we present a stable structure of the solvated complex formed between uPA and uPAR (uPA-uPAR) and investigate the specific interactions between uPA and uPAR by ab initio fragment molecular orbital (FMO) calculations. The result indicates that the electrostatic interactions between the charged amino acid residues existing in both uPA and uPAR make a large contribution to the binding between uPA and uPAR. In particular, Lys23, Lys46, Lys98 and Lys61 of uPA are found to have strong attractive interactions with uPAR. To elucidate the effect of these residues on the interactions between uPA and uPAR, we substituted each of them with the uncharged amino acid Leu and investigated the interactions between the mutated uPA and wild-type uPAR. The interaction energies indicate that Lys46 and Lys98, which bind uPA to the rim of the central ligand-binding cavity of uPAR, make greater contributions to the binding between uPA and uPAR than Lys23, which is positioned at the bottom of the ligand-binding cavity of uPAR. The effect of hydrating water molecules located between uPA and uPAR is also investigated to be significant for the specific interactions between uPA and uPAR. These results are expected to be informative for developing new peptide antagonists that block the binding of uPA to uPAR.     

Damage to seagrass and seaweed beds in Matsushima Bay,Japan, caused by the huge tsunami of the Great East Japan Earthquake on 11 March 2011

Damage to seagrass and seaweed beds caused by the huge tsunami of the Great East Japan Earthquake on 11 March 2011 was investigated in Matsushima Bay, Miyagi Prefecture, Japan, by comparing satellite images taken before the tsunami in November 2009 and after the tsunami in May 2011. The results showed that the tsunami destroyed 220 ha of seagrass and seaweed beds, from 320 ha in 2009 to 100 ha just after the tsunami. Zostera marina beds on the sandy and muddy bottom were rather severely damaged compared with brown seaweed beds of Sargassum horneri on the rocky substrate. Substrates of the beds and directions of the tsunami seem to be responsible for the magnitude of the damage to the beds. Maps of the spatial distributions of the beds before and after the tsunami can provide information for the restoration of seagrass and seaweed beds as natural infrastructures of coastal fisheries resources.