Manufacturing and Compressive Deformation Behavior of High-Strength Aluminum Coating Material Fabricated by Kinetic Spray Process

The compressive deformation behavior in the thickness direction of a kinetic-sprayed pure-aluminum layer whose thickness is ~15 mm was investigated. The yield strength of coating material was 200 MPa, and a unique strain softening phenomenon occurred even at room temperature. Due to the initial severely deformed structure of the kinetic-sprayed coating material based on the results of microstructure analysis, the production of high-strength metal bulk materials using kinetic spray processes was deemed possible.     

Identification and characterisation of coumarins from the roots of Angelica dahurica and their inhibitory effects against cholinesterase

The current research was the first to investigate coumarins and their cholinesterase inhibitory activities from Angelica dahurica roots. The ethanol extract of this species (100 μg/ml) possessed inhibitory effects against human acetylcholinesterase (hAChE) and butylcholinesterase (BChE) with IC₅₀ values of 26.40 and 14.71 μg/ml, respectively. To evaluate the compounds responsible for these activities, the ethanol extract was chromatographed, which yielded ten coumarins, including isoimperatorin (1), imperatorin (2), senbyakangelicol (3), oxypeucedanin (4), byakangelicol (5), t-OMe-oxypeucedanin hydrate (6), t-OMe-byakangelicin (7), angelol H (8), byakangelicin (9), and oxypeucedanin hydrate (10). Among them, coumarin 5, 7, and 9 showed potent inhibition with IC₅₀s of 46.3, 39.0, and 55.4 μM (hAChE) as well as 45.2, 25.6, and 42.4 μM (BChE), respectively. Moreover, their inhibition modes against two cholinesterases exhibited noncompetitive. The individual coumarin contents were remarkable differences, especially, oxypeucedanin (4) was the most predominant compound (8710.9 μg/g), representing approximately 55.0% of the total content.     

Efficiency improvement opportunities for personal computer monitors: implications for market transformation programs

Displays account for a significant portion of electricity consumed in personal computer (PC) use, and global PC monitor shipments are expected to continue to increase. We assess the market trends in the energy efficiency of PC monitors that are likely to occur without any additional policy intervention and estimate that PC monitor efficiency will likely improve by over 40 % by 2015 with saving potential of 4.5 TWh per year in 2015, compared to today's technology. We discuss various energy-efficiency improvement options and evaluate the cost-effectiveness of three of them, at least one of which improves efficiency by at least 20 % cost effectively beyond the ongoing market trends. We assess the potential for further improving efficiency taking into account the recent development of universal serial bus-powered liquid crystal display monitors and find that the current technology available and deployed in them has the potential to deeply and cost effectively reduce energy consumption by as much as 50 %. We provide insights for policies and programs that can be used to accelerate the adoption of efficient technologies to further capture global energy saving potential from PC monitors which we estimate to be 9.2 TWh per year in 2015.     

Submicrometer particle removal indoors by a novel electrostatic precipitator with high clean air delivery rate,low ozone emissions,and carbon fiber ionizer

A novel positive‐polarity electrostatic precipitator (ESP) was developed using an ionization stage (0.4 × 0.4 × 0.14 m³) with 16 carbon fiber ionizers in each channel and a collection stage (0.4 × 0.4 × 0.21 m³) with parallel metallic plates. The single‐pass collection efficiency and clean air delivery rate (CADR) were measured by standard tests using KCl particles in 0.25–0.35 μm. Performance was determined using the Deutsch equation and established diffusion and field charging theories and also compared with the commercialized HEPA filter‐type air cleaner. Experimental results showed that the single‐pass collection efficiency of the ESP ranged from 50 to 95% and decreased with the flow rate (10–20 m³/min), but increased with the voltage applied to the ionizers (6 to 8 kV) and collection plates (?5 to ?7 kV). The ESP with 18 m³/min achieved a CADR of 12.1 m³/min with a voltage of 8 kV applied to the ionization stage and with a voltage of ?6 kV applied to the collection stage. The concentration of ozone in the test chamber (30.4 m³), a maximum value of 5.4 ppb over 12 h of continuous operation, was much lower than the current indoor regulation (50 ppb).     

Site-specific synthesis of ZnO nanocrystalline networks via a hydrothermal method

ZnO nanocrystalline networks (NCNWs) consisting of percolating nanocrystals with irregular shape and size were synthesized using Al seed layers in a hydrothermal process. Various thicknesses of Al films were used to assess the effects of film thickness on the formation of ZnO NCNWs; the coverage and size of the ZnO nanocrystals increased with an increasing Al film thickness. In addition, by exploiting the seed layer-dependent crystal growth behaviors, two distinctly different ZnO nanostructures, nanorods on ZnO seed and NCNWs on Al seed, could be selectively achieved on the same substrate under the same growth conditions. Spectrally- and spatially-resolved investigations of these two ZnO nanostructures were performed using cathodoluminescence, which provided a significant opportunity to study the effect of the nanostructures on the luminescent characteristics. The ZnO NCNWs have an extremely high surface to volume ratio and sufficient inter-space, which enabled the conversion of the surface property from hydrophilic to superhydrophobic.     

Weighted aggregation and fuzzy-concept-guided signal resemblance and expansion for video format conversion

In this paper, we propose an efficient deinterlacing method for HDTV that preserves image structures, edges, and details. In the human visual system, the eyes are more sensitive to high-frequency information such as edge details than low-frequency information such as image background. Therefore, averaging low-pass filter results is not effective for image enhancement. The proposed method is a weighted filtering approach that generates a half-pixel 9-by-9 edge-based line average window. We also propose pixel-resemblance- and pixel-expansion-based fuzzy weights, which are assigned using a triangular membership function. Compared to conventional format conversion methods, the proposed method outperforms all benchmarks in terms of both objective and subjective qualities.     

SiO2 ceramic nanoporous substrate-reinforced sulfonated poly(arylene ether sulfone) composite membranes for proton exchange membrane fuel cells

Porous substrate-reinforced composite membranes have been extensively investigated due to their promising application to proton exchange membrane fuel cells (PEMFC). In this study, we develop a new ceramic-based reinforcing porous substrate, which consists of hygroscopic silica (SiO₂) nanoparticles interconnected by 3-glycidoxypropyltrimethoxysilane (GPTMS)-based silicate binders and a poly(paraphenylene terephthalamide) (PPTA) nonwoven support. This unusual ceramic substrate is featured with the strong mechanical strength, well-developed nanoporous structure (i.e., nanosized interstitial voids formed between the close-packed SiO₂ nanoparticles), high hydrophilicity, and more notably, good water retention capability. The nanostructured pores of the ceramic substrate are subsequently impregnated with sulfonated poly(arylene ether sulfone) (SPAES, degree of sulfonation = 49.3%). In comparison to a pristine SPAES membrane, the ceramic substrate-reinforced SPAES composite membrane offers the significantly improved dimensional change and also effectively mitigates the steep decline of proton conductivity at low humidity conditions, which is further discussed by considering the state of water in the reinforced composite membrane.     

Application of A2O moving-bed biofilm reactors for textile dyeing wastewater treatment

A three-stage pilot-scale moving-bed biofilm reactor (MBBRs, anaerobic-anaerobic-aerobic in series) was investigated to treat textile dyeing wastewater. Each reactor was filled with 20% (v/v) of polyurethane-activated carbon (PU-AC) carrier for biological treatment. To determine the optimum operating conditions of MBBRs, the effect of PUAC carrier, its packing percentage (v/v%) and pH control on COD removal were analyzed by batch experiments. The MBBRs were inoculated with activated sludge obtained from a local dyeing wastewater treatment plant. The MBBR process removed 86% of COD and 50% of color (influent COD=608 mg/L and color=553 PtCo unit) using relatively low MLSS concentration (average 3,000 mg/L in biomass attached to PU-AC carrier) and hydraulic retention time (HRT=44 hr). The MBBR process showed a promising potential for dyeing wastewater treatment.     

The influence of nanoscale defects on the fracture of multi-walled carbon nanotubes under tensile loading

We report the mechanical behavior of a unique type of multi-walled carbon nanotube (MWCNT) and an acid-treated version of this MWCNT type that have nanoscale defects on their surfaces from the acid treatment. These defects, from scanning electron microscope (SEM) and transmission electron microscope (TEM) imaging have a ‘channel-like’ appearance, as if a ring of material was cut away from the MWCNT around the circumference. The mechanical properties of individual MWCNTs have been experimentally shown to strongly depend on their structure and structural disorder can drastically reduce the mechanical properties. Tensile-loading experiments using a nanomanipulator tool operated inside a SEM revealed that the tensile strengths of 10 pristine MWCNTs ranged from ～ 2 to ～ 48 GPa (mean 20 GPa). For 10 acid-treated MWCNTs with channel-like defects, tensile strengths ranged from ～ 1 to ～ 18 GPa (mean 6 GPa, thus roughly 70% lower than those of the pristine MWCNTs). Microstructural observations revealed that the fracture of the acid-treated MWCNTs occurred at a channel-like defect region in 8 of the 10 samples. This indicates that the channel-like defects associated with the acid etching are typically going to be the weakest points in the acid-treated MWCNT structure and that stress concentration is present at the defect region.     

Circularly Polarized Luminescence Induced by Chiral Super Nanospaces

A simple methodology is developed to realize chiroptical function induced through superstructural chirality of a matrix of helical nanofilaments formed by achiral molecules. In this work, circularly polarized luminescence is demonstrated in nanosegregated mesophase comprising only achiral molecules. An achiral molecular mixture of a bent‐core host and a rod‐like guest blended with a fluorescent dye is prepared. Circularly polarized luminescence confirms that the chiral superstructure consisting only of achiral molecules may serve as a chiral super nanospace for inducing chiral emissions from the fluorescent dye that exhibits rod‐like molecular ordering. In other words, the formation of a chiral superstructure by the segregated rod‐like molecules embedded in helical nanofilaments (bent‐core molecules) is confirmed. The results provide a novel strategy for constructing dissymmetric circularly polarized luminescence materials based on achiral molecules, which is potentially applicable in future information and display technologies.