Effect of annealing on photovoltaic properties and microstructure of conventional and inverted organic solar cells using active bilayer based on liquid‐crystal semiconducting polymer and fullerene

Conventional and inverted organic solar cells of poly[9,9‐dioctyl‐fluorene‐co‐bithiophene] (F8T2) as liquid‐crystal semiconducting polymer and fullerene as electron acceptor were fabricated and characterized. An effect of thermal treatment of the films on annealing condition near glass transition was investigated for tuning optimization and improving the photovoltaic and optical properties. Annealing treatment below the glass transition improved the photovoltaic performance and carrier diffusion in crystal growth of active layer. The X‐ray diffraction patterns indicate a crystalline structure with molecular order of F8T2 in crystal index, 100 as a layer distance between sheets of F8T2 chains. The photovoltaic properties were based on molecular interactions with molecular ordering in active layer at crystal state. As the photovoltaic mechanisms, the F8T2 thin film as p‐type semiconducting polymer worked for electron‐donor layer to support light‐induced generation, carrier diffusion and charge transfer near interface in active layer. Copyright © 2014 John Wiley & Sons, Ltd.     

Investigation and consideration on landslide zoning of multiple slope failures and debris flows of 2014 disaster in Hiroshima,Japan

This study was intended to examine the mechanism of multiple slope failures and debris flows that occurred in the outskirts of Hiroshima on 20th August 2014. A field survey of the mountain stream where large-scale damage was incurred was carried out and the characteristics of debris flows which made serious damages were investigated. There were five findings of this study. (1) The initiation of debris flows was not limited to thin and planar shallow failures, but also showed V or U shapes, where the eroded sediments seemed to be pushed out by artesian water, and the eroded depth exceeded several meters at many locations. (2) There were areas with high permeability, such as faults, fracture zones, and joints in Mt. Abusan. It is inferred that the constantly present groundwater in these areas became artesian water because of a large amount of rainfall in upstream locations. This quickly destabilized the slopes on a large scale. (3) There were at least three estimated debris flows at the mountain stream above Midorigaoka prefectural apartments in Yagi 3-Chome, where the worst damage occurred. The mountain stream near Abu-no-Sato housing complex also had multiple debris flows. Here, the secondary debris flow changed its flow path because of the presence of sediments from an earlier debris flow. (4) The actual volumes of flowed mass were much larger than that predicted at 11 of the 18 mountain streams in Midori-i and Yagi districts. The volume of the mass of five of these mountain streams was more than twice the estimated volume. It is necessary to modify the method of calculating the volume of unstable sediments in the mountain stream. (5) It was found that the devastating damage of buildings and human lives took place in the areas well beyond the special restricted zones. The present method to designate the special restricted zone must be revised considering such problems as the underestimation of the volume of unstable sediments, the assumptions of a single debris flow and on the direction of debris flow, and the effect of the difference on rock and soil types.     

Rh/γ-Al2O3 Catalytic Layer Integrated with Sol–Gel Synthesized Microporous Silica Membrane for Compact Membrane Reactor Applications

An efficient and compact catalytic membrane reactor for reforming of CH₄ was developed by integrating a hydrogen perm-selective silica membrane with an Rh/-Al₂O₃ catalyst layer. The catalytic layer was sandwiched between the outer surface of the -Al₂O₃ support tube and the silica membrane with an aim of improving the heat and mass transfer rates through the system and to simplify the reactor geometry. The system showed improved efficiency for reforming of CH₄ at comparatively lower operating temperatures and steam to C molar ratios than the conventional fixed-bed steam reforming systems. Under optimized conditions, a nearly 25-30% improvement from the equilibrium conversion level was achieved as a result of abstraction of hydrogen from the product stream by the silica membrane integrated with the catalyst layer. The performance of the system was evaluated as a function of various process parameters. Because of the compactness and efficiency, the present system emerges as a promising alternative to the conventional membrane reactors, which possess separate catalytic and membrane units.     

Corrosion characteristics of reduced activation ferritic steel, JLF-1 (8.92Cr–2W) in molten salts Flibe and Flinak

Static corrosion tests were performed in molten salts, LiF–BeF₂ (Flibe) and LiF–NaF–KF (Flinak), at 500 °C and 600 °C for 1000 h. The purpose is to investigate the corrosion characteristics of reduced activation ferritic steels, JLF-1 (8.92Cr–2W) in the fluids. The concentration of hydrogen fluoride (HF) in the fluids was measured by slurry pH titration method before and after the exposure. The HF concentration determined the fluoridation potential. The corrosion was mainly caused by dissolution of Fe and Cr into the fluids due to fluoridation and/or electrochemical corrosion. Carbon on the surface might be dissolved into the fluids due to the corrosion, and this resulted to the decrease of carbide on the surface. The corrosion depth of the JLF-1 specimen, which was obtained from the weight losses, was 0.637 μm in Flibe at 600 °C and 6.73 μm in Flinak at 600 °C.     

LiErO2 formation on Er2O3 in static and natural convection lithium

Er₂O₃ is candidate material for insulating coating to prevent the magnetohydrodynamic (MHD) pressure drop in the self-cooled liquid Li blanket system. Although Er₂O₃ is stable material, detailed chemical behavior in liquid Li is not clear. Corrosion behavior of bulk Er₂O₃ in Li is investigated in static and flowing condition in the present study. After these tests, good compatibility of Er₂O₃ was confirmed and slight formation of LiErO₂ was detected by XRD analysis. This chemical behavior did not change in a static and flowing tests, however some of the corrosion product of LiErO₂ was removed easily by the Li flow. Intensity of LiErO₂ peaks in XRD spectrum suggests that the temperature gradient may affect the reaction rate in the natural convection loop. Since corrosion rate of Er₂O₃ is very small, slight change in state will be important information to evaluate lifetime of coating.     

Superoxide dismutase-based third-generation biosensor for superoxide anion

A third-generation biosensor for superoxide anion (O2-) was developed by immobilizing superoxide dismutase (SOD) on a self-assembled monolayer of cysteine on gold electrode; i.e., a SOD/cysteine-modified gold electrode (SOD/Cys/Au) was fabricated. A rapid and direct electron transfer of SOD was realized at the gold electrode by using the cysteine molecule as an electron-transfer promoter. The promoted direct electron transfer of SOD and biomolecular recognition by the exploitation of specific and significant enzyme-substrate reactivity of SOD toward O2- combined with the low operating potential enabled a sensitive measurement of O2-. At SOD/Cys/Au, O2- could be specifically oxidized and reduced to O2 and hydrogen peroxide, respectively, through the inherent catalytic reaction of SOD. This allowed us to measure O2- by polarizing the electrode both anodically and cathodically. We could successfully measure O2- by suitably polarizing the electrode, typically at 300 and -200 mV versus Ag/AgCl without the virtual interference from physiological levels of H2O2, ascorbic acid, uric acid, and metabolites of neurotransmitters. The response mechanism of SOD/Cys/Au to O2- and its sensor characteristics are also presented and discussed.     

N—甲硅烷基—1—氮杂烯丙基负离子与α,β—不饱和酮的反应

三甲基甲硅烷基异恶唑的负离子与Ｐ－取代苄腈（２ａ）－（２ｅ），反应制得的Ｎ－甲硅在－１－氮杂烯丙基负离子（３ａ）－（３ｅ），央无水四氢呋喃存在下与过量查耳酮反应，生成相应的吡啶衍生物（５ａ）－（５ｅ），回收率达４０－７０％。