CO2 Decomposition by Oxide Ceramics Intercalated in Layered Compound

Iron oxide polymers intercalated and/or loaded within täniolite have been studied as a CO₂ decomposition medium. Fe²⁺ was exchanged for Li⁺ in täniolite, oxidized by air-bubbling at 60°–70°C. The basic d -spacing (13.75 Å in the Li⁺ form) was expanded to give 14.86 Å in the Fe²⁺ form. Oxidation by air in the form of suspension gave a 15.3-Å phase, which was ascribed to formation of magnetite within the interlayer. The interlayer distance of the intercalated phase remained the same upon heating at 300°C. The magnetite–intercalated täniolite was heated to activate in a H₂ and/or H₂O steam. CO₂ decomposition reactivity at 300°C has been evidenced by evolution of CO gas. The high reactivity for CO₂ decomposition is ascribed to the highly dispersed iron oxide ceramics within the interlayer of täniolite Li[(Mg₂Li)(Si₄O₁₀)]F₂ n H₂O.     

Evaluation of material properties and internal damage within CFRP and CFRP/Al sandwich panels due to impact loading

In the present paper, damage development within Carbon fiber reinforced plastic (CFRP) laminates and CFRP/Aluminum (Al) honeycomb core sandwich panels by impact loading was evaluated, and change in material properties due to the damage development was investigated. Falling weight impact tests, 3-point bending tests and cross-sectional observation were carried out. As results, it is found that falling rate of bending elastic modulus due to internal damage in the laminate only is lower than that in the upper face-sheet of the sandwich panel, and that difference in the falling rate between them becomes maximum at the impact energy of 5.1 J. As a result of investigating the relationship between reduction in bending elastic modulus and internal damage development, the reduction is caused by delamination within CFRP laminates mainly. Since total length of cracks in CFRP/Al honeycomb core sandwich panels is smaller than that in the laminates only, the sandwich panels have high impact tolerance because of absorption of impact energy by damaging Al honeycomb core.     

Social acceptance toward a childcare support robot system: web-based cultural differences investigation and a field study in Japan

This paper investigates people’s social acceptance of a childcare support robot system and compares it with existing childcare technologies (anesthesia during labor and baby food, i.e. processed food and formula milk) through web-based questionnaires between Japan and USA and a field study in Japan. We investigated social acceptance through four scales: intention to use, safety and trustworthiness, negative attitudes, and decreasing workload. For this paper, our participants included 400 people (200 from each country) in Japan and USA located through a web-based survey who answered questionnaires about the four scales to investigate their social acceptance of childcare support technologies. Our web-based survey results indicate that our system’s concept was evaluated lower than current childcare support technologies in both Japan and USA. We also conducted a field trial with 30 additional people in Japan and through their actual experiences investigated their evaluations of the prototype of our childcare support robot system.     

Functional Equivalence Verification Tools in High-Level Synthesis Flows

Editor's note:High-level synthesis facilitates the use of formal verification methodologies that check the equivalence of the generated RTL model against the original source specification. The article provides an overview of sequential equivalence checking techniques, its challenges, and successes in real-world designs.—Andres Takach, Mentor Graphics     

Experimental and numerical investigation of catalytic PM combustion in a fluidized bed type PM removal device for low-temperature continuous regeneration

A fluidized bed filter can perform highly efficient PM collection and low-temperature continuous regeneration. However, to further reduce continuous regeneration temperature, a rough surface bed particle was selected herein. It is expected that the rough surface increases and stabilizes doped catalyst on bed particle even in fluidized bed. This bed particle can stably support 9.48 g-catalyst/kg-bed particle of doped catalyst versus 1.58 g-catalyst/kg-bed particle in previous research. This increase in catalyst amount increases the probability of good PM-catalyst contact, and collection efficiency can easily maintain its initial value due to catalytic PM combustion. PM combustion also depends on fluidization. Thus, combustion kinetics in a fluidized bed was investigated via a newly developed thermogravimetric analyzer that considered PM-gas relative velocity, and a constructed kinetic model was applied to numerical simulation. PM combustion obeyed an Arrhenius relationship, and the effect of PM-gas relative velocity was included in the kinetic model as a mass transfer term. A continuous regeneration experiment was conducted under optimal conditions, and the continuous regeneration temperature is 330 °C. As water vapor occurs in combustor exhaust, we added 10 vol% water vapor and found that the continuous regeneration is further reduced to 300 °C.     

Effects of MoOx modification on photocatalytic activity of hydroxyapatite and Ti-doped hydroxyapatite

Titanium-doped hydroxyapatite (Ti-HAp, (Ca_10-2x, Ti_x, □_x) (PO₄)₆(OH)₂, □: defect in Ca site) and hydroxyapatite (HAp, Ca₁₀(PO₄)₆(OH)₂) powders were modified with an ethanol solution of molybdenyl acetylacetonate (MoO₂(C₅H₈O₂)₂) using chemisorption calcination cycle (CCC) technique, which provides metal oxide clusters. Their photocatalytic activity under UV illumination was evaluated by the decomposition of gaseous 2-propanol. The photocatalytic activity of the Mo-modified Ti-HAp samples increased concomitantly with increasing Mo concentration up to 0.72% against P. The highest photocatalytic activity of Mo-modified Ti-HAp was about 13 times higher than that of Ti-HAp. The signal appearance of Mo(V) in electron spin resonance spectra and the decrease of photoluminescence intensity suggest electron transfer from the Ti-hybridized band to the MoO_x cluster, which suppresses recombination of the photoinduced electron and hole pairs. The photocatalytic activity of Mo-modified HAp samples was attributed to HOMO–LUMO excitation of MoO_x cluster.     

Highly efficient white OLEDs with single solution‐processed emitting layer fabricated by one‐step coating using self‐layered technique

We propose a self‐layered technique to form an emitting layer with a pseudo‐multilayered structure by one‐step coating and demonstrate the feasibility of its concept. We also fabricated a highly efficient white organic light‐emitting diode with the proposed technique. A maximum power efficiency of 70 lm/W was obtained by improving the effective radiation efficiency, carrier balance efficiency, and light‐extraction efficiency.     

Noble metal catalysts highly-dispersed on Sm-doped ceria for the application to internal reforming solid oxide fuel cells operated at medium temperature

The synthesis of MTBE was studied in the gas phase at elevated temperatures (up to 175°C) and low pressures (150 kPa) where the MTBE formation rate is limited by thermodynamic equilibrium, using various solid acid catalysts (Amberlyst-15 resin, silica-alumina, HY and H-ZSM-5 zeolites). All the zeolites studied were found to exhibit better selectivities to MTBE than the commercially used Amberlyst-15 resin catalyst. The formation of byproducts increased with increasing temperature and appeared to have a strong enhancing effect on catalyst deactivation. H-ZSM-5 seems to be more suitable for high temperature formation of MTBE because of its excellent selectivity towards MTBE and low deactivation behavior.     

Adiabatic two-phase flow in narrow channels between two flat plates

Adiabatic cocurrent flow of air and water through a narrow passage between two flat plates 240 mm long and 99mm wide with gap-widths of 0.778 mm and 1.465 mm was investigated for six different orientations: Vertically upward and downward, 45^° inclined upward and downward, and horizontal flows between horizontal plates and between vertical plates. Except for horizontal flow between vertical plates, the effects of gap width and flow channel orientation on flow pattern, void fraction and friction pressure drop were found to be small in narrow channels. The void fraction and two-phase friction multiplier data could also be reasonably correlated in terms of the Martinelli parameter. For horizontal flow between vertical plates, both the void fraction and friction multiplier data showed strong mass velocity effects. Several friction pressure drop correlations were tested for applicability to the narrow channels including a separated flow model proposed in this work.