Mineral matter effects on air-oxidation of cokes from a coking coal

Indigenous mineral matter in coal affects the chemical reactivity of resulting cokes through both catalytic graphitization and catalytic gasification. The significance of both catalytic effects on air-oxidation was examined using cokes from a medium-volatile bituminous coking coal with 9 wt% mineral matter. Catalytic graphitization by mineral matter enhanced the reactivity of the resulting coke in spite of the formation of highly crystalline carbons. This effect, however, was less than that of catalytic gasification by mineral matter. The coke from the acid-treated predemineralized coal exhibited no catalytic effects but was the most reactive. The implications of these results are discussed in detail.     

A flexible OLED display with an OTFT backplane made by scalable manufacturing process

Abstract— A full‐color top‐emission AMOLED display driven by an organic TFT backplane manufactured using a scalable, lift‐off‐free, and shadow‐mask‐free process has been developed. It was shown that cost‐efficient copper can be used for S/D electrodes. The display has shown no significant degradation over a storage life of more than 10 months and operation over 25 hours during which the display is bent over 10,000 times.     

Extensional viscosity of silica dispersions

The rheological behavior in extensional flow was investigated for silica dispersions in polymer solutions using the tubeless syphon technique. The flow field of tubeless syphon is unsteady in the Lagrangian sense; hence the data are taken under transient stress conditions. Due to the insensitive nature of the extensional rate to flow rate, the extensional viscosities at different flow rates lie very close to a single curve, once they are plotted against strain. Two important points are noted with regard to the behavior of the dispersions. First, the extensional viscosity decreases with increasing particle concentration. Second, the viscosity growth curves of the dispersions can be superimposed by a vertical shift, but the curve shape differs from that of the medium. This implies a change in the relaxation time.     

Morphology of Oxide Particles Made by the Emulsion Combustion Method

Various oxide powders were prepared by the emulsion combustion method (ECM) using metal precursors, kerosene, and a surfactant. The product particles were characterized by transmission electron microscopy (TEM), nitrogen adsorption, and X-ray diffraction. Hollow γ-Al₂O₃ particles were produced from aluminum nitrate or chloride precursors dispersed in air, whereas dispersion of the precursor emulsion in oxygen resulted in solid α-Al₂O₃ particles. Hollow spheres were obtained also for TiO₂, ZrO₂, and Y₂O₃ by ECM of TiCl₄, zirconium oxynitrate, and yttrium nitrate in aqueous solution. A simple method was developed to predict the thickness and diameter of hollow particles using the nitrogen adsorption data and initial droplet concentration of the ECM spray. The TEM diameter and shell thickness of hollow particles were consistent with those predicted. In contrast, solid particles were formed by ECM for ZnO, Fe₂O₃, CeO₂, and MgO from aqueous solutions of their corresponding nitrates.     

Laser‐addressed full‐color photo‐quality rewritable sheets based on thermochromic systems with leuco dyes

We have developed a laser‐addressed full‐color photographic quality rewritable sheet. The sheet was composed of a vertically stacked Cyan/Magenta/Yellow‐thermochromic system with a mixture of leuco dyes, developers and photothermal conversion agents in a polymer matrix. The sheet was simply manufactured by roll‐to‐roll (R2R) processes. Writing and erasing were performed by scan of near‐infrared laser light. It achieved full‐color photographic quality images with a wide color gamut with 70% coverage of the Specifications for Web Offset Publications (SWOP) standards and a high resolution of 426 ppi. Clear rewritability has also been confirmed. Non‐contact laser writing has other advantages in that it can create an image under a protection film, and it has form factor flexibility. We have developed a reliability model for high‐temperature storage and a light fastness test. This model showed a good agreement with experimental data, and the lifetime of an image was estimated to be over 8 years under ambient conditions. This technology will create applications for on‐demand rewritable image design while saving power and reducing the use of paper, which will eventually contribute to a sustainable society.     

Spontaneous Polarization Screening Effect and Trap-State Density at Grain Boundaries of Semiconducting Barium Titanate Ceramics

The grain-boundary trap-state density and the polarization screening effect were studied for a series of semiconducting PTCR barium titanate ceramic samples with different manganese (Mn) additives and different thermal treatments. The grain-boundary resistance and capacitance data were measured by the ac complex impedance method. The grain-boundary data obtained were analyzed using a simple double-depletion-layer model and an absolute-zero-temperature approach for the Fermi distribution function for the boundary trap states. The energy density distributions of the boundary trap states were found to be V-shaped for the energy range studied, from 0.35 to 1.35 eV, as measured from the conduction band downward. The "neutral" Fermi level at the grain boundary is taken as 1.35 eV and the bulk Fermi level is taken as 0.15 eV from the conduction band. For the samples without the Mn additive, the PTCR effect is controlled by the trap densities located near 0.35 eV. The trap centers are believed to be barium and oxygen vacancies, or chemisorped oxygens. For the samples with Mn additives, the trap densities increase dramatically near 1.35 eV and play a dominant role in the PTCR effect. These trap centers are believed to be Mn⁴⁺ ions at the titanium sites. The charge-compensation effect of spontaneous polarizations on the trap charges was found to be linearly proportional to the total amount of trap charges at that temperature.     

Photoactive and Adsorptive Niobium-Doped Anatase (TiO2) Nanoparticles: Influence of Hydrothermal Conditions on their Morphology, Structure, and Properties

Anatase-type TiO₂ nanoparticles with adsorptivity and improved photocatalytic activity for the decomposition of methylene blue (MB) in its aqueous solution, which contained up to 10 mol% niobium by forming solid solutions with niobium oxide, were directly synthesized from precursor solutions of TiOSO₄ and NbCl₅ under three hydrothermal conditions in the absence and presence of urea and aqueous ammonia at 180°C for 5 h. The influence of the hydrothermal conditions on the crystallite growth, morphology, specific surface area, adsorptivity, and photocatalytic activity of niobium-doped TiO₂ was investigated. The crystallite growth of anatase was enhanced by the presence of the niobium component. The 10 mol% niobium-doped TiO₂ that was prepared under the hydrothermal condition in the presence of urea had fine crystallites (11 nm) and high specific surface areas (135 m²/g), which showed the most enhanced photocatalytic activity and the highest adsorptivity. The hydrothermal treatment under weak basic conditions and formation of solid solutions with niobium oxide brought about a considerable increase in the adsorption of MB for the anatase-type TiO₂.     

Hypolipidemic Effects of Phospholipids (PL) Containing n-3 Polyunsaturated Fatty Acids (PUFA) Are Not Dependent on Esterification of n-3 PUFA to PL

Phospholipids (PL) containing n‐3 polyunsaturated fatty acids (PUFA) have beneficial effects of maintaining and promoting health compared with triacylglycerols (TAG) containing n‐3 PUFA or general PL. This study evaluated the effects of dietary PL containing n‐3 PUFA and elucidated the effects of the glycerophosphate structure and n‐3 PUFA on fatty acid (FA) metabolism in rats. Rats were fed a basal diet containing soybean oil alone, TAG containing n‐3 PUFA (1.8 %), soybean PL (2.7 %), PL containing n‐3 PUFA (2.7 %), or TAG containing n‐3 PUFA (1.8 %) + soybean PL (2.7 %). The present n‐3 PUFA‐supplemented diets had similar FA compositions, and the PL diets had similar PL compositions. TAG containing n‐3 PUFA reduced serum TAG contents, but did not affect serum cholesterol contents compared with soybean oil alone. PL diets containing n‐3 PUFA and the combination of TAG containing n‐3 PUFA and soybean PL resulted in decreased serum and liver TAG contents compared with the diet containing soybean oil alone, reflecting enhanced liver FA β‐oxidation. The results of this study show that TAG containing n‐3 PUFA with added soybean PL affects serum and liver TAG and cholesterol contents to a similar degree as PL containing n‐3 PUFA. TAG containing n‐3 PUFA and soybean PL are widely used as functional food ingredients and pharmaceutical constituents and are inexpensive compared with PL containing n‐3 PUFA. Therefore, the combination of TAG containing n‐3 PUFA and soybean PL has potential as a useful and inexpensive component of functional foods.     

Backlight imaging tomography for slug flows in straight and helical tubes

Backlight imaging tomography is used to experimentally investigate interfacial structures of gas–liquid two-phase flow in circular tubes. The tomography method is based on the attenuation of visible light that causes the inside of the liquid phases to be colored with dye. Increasing the number of light projections provides accurate phase distributions to be reconstructed by a linear backward projection scheme. After the reconstruction performance is examined with numerical simulations for several test cases, the method is applied to slug flows that have complicated 3D interfaces from turbulence. Interfacial structures are compared between straight and helical tubes to determine the effect of centrifugal acceleration. The result demonstrates that centrifugal acceleration provides a liquid-clinging layer on the inner wall against gravity while a high-speed collision of liquid with the top wall happens in a straight tube.     

Antiestrogenic Activity of Extracts of Diesel Exhaust Particulate Matter in MCF-7 Human Breast Carcinoma Cells

Diesel exhaust particulate matter (DEP) was collected from three commercial diesel engine vehicles and DEP extracts (DEPEs) were prepared from each. The estrogenic and antiestrogenic activities of the DEPE samples were examined using an estrogen response element (ERE)-driven luciferase reporter gene assay in MCF-7 human breast cancer cells. While DEPE samples did not exhibit significant estrogen agonist activity alone, they suppressed 17 g -estradiol (E 2 )-induced luciferase activity without decreasing cell viability. Several polycyclic aromatic hydrocarbons (PAHs) acting as aryl hydrocarbon receptor (AhR) agonists were detected in the DEPEs and their concentrations were higher in DEPE samples with higher antiestrogenic activity. DEPE samples elevated cytochrome P450 (CYP) 1A1 activity. f -Naphthoflavone, an AhR antagonist, and SKF-525A, a nonselective CYP inhibitor, reversed and enhanced the antiestrogenic activity of DEPE samples, respectively. These results demonstrate that DEPE has antiestrogenic activity and this effect is primarily due to the PAH constituents acting as AhR agonists.