Aging and thermal stability of Mg/SiC and Mg/Y2O3 reflection multilayers in the 25-35 nm region

Reflection measurements in the 25-35 nm region were made for Mg/SiC and Mg/Y2O3 multilayers kept in a low-humidity atmosphere for 4 or 5 years. Aged Mg/SiC multilayers keep their reflectances, and the reflectance value at 31.2 nm is 0.44 at 10 degrees of the normal angle of incidence. Aged Mg/Y2O3 multilayers change reflectance as top layer materials, and the best value at 30.1 nm is 0.40 at 10 degrees. Reflection measurements are also made for Mg-based multilayers that are annealed from room temperature to 400 degrees C at 50 degrees C intervals. Both multilayers keep their reflectance at annealing temperatures of 200 degrees C. These results suggest that both Mg-based multilayers can be applied to practical optics.     

Chemical Removal of CeO2 Segregated on the Surface of CeO2–ZrO2 Binary Oxides for Improvement of OSC

A chemical treatment to remove residual CeO₂ phase on CeO₂–ZrO₂ (CZ) solid solution was carried out. A CZ was treated by H₂O₂ for the reduction of Ce⁴⁺ to Ce³⁺ and then HNO₃ for the dissolution of Ce³⁺ compounds (H–CZ). H₂-TPR, TEM-EDX and XPS analyses revealed the removal of CeO₂ phase and the homogeneous distribution of Ce species. About 20% improvement in oxygen storage capacity (OSC) of H–CZ was confirmed at 773 K by the weight measurements under H₂/N₂ and air atmospheres, indicating that the HNO₃/H₂O₂ treatment was effective to avoid the deterioration of the OSC by segregated CeO₂ on the CZ binary oxides.     

Flow characteristics of a small moving bed downcomer with an orifice under negative pressure gradient

Behaviour of gas-solid mixtures in a small moving bed downcomer operating under negative pressure gradient has been investigated experimentally, because flow characteristics in a downcomer are important factors in powder handling processes, such as a multi-stage spouted bed or a circulating fluidized bed. In this study, a small downcomer in which the moving bed height could be controlled was employed with the intention of using a downcomer as a connecting tube in a multi-stage spouted bed. Based on experimental observation, the moving bed flow changed from smooth flow (Region(I)) to slip-stick flow (Region(II)) and then changed from slip-stick flow to intermittent flow (Regime(III)), as the gas pressure gradient in the downcomer was increased. In this study, the critical point for steady-state (Region(I)) operation was also examined experimentally and theoretically, by using eight kinds of solid particles (Geldart B, D and A powders) and six different orifice sizes which were used to restrict solids flow at the base of the downcomer. As a result, a correlation of solids flow rate in the stable moving bed downcomer under negative pressure gradient was derived and the critical point between stable and unstable flow was explained by the proposed model.     

Physicochemical characteristics of rapidly dried onion powder and its anti-atherogenic effect on rats fed high-fat diet

Rapidly dried onion (Allium cepa L. cv. Momiji No. 3) powder (OP) prepared from the outer layers (from second to fourth scale leaves from the surface) of onion bulbs was analysed for its quercetin and polyuronide contents, the effects of enzymatic treatment and the anti-atherogenic effect on rats fed a high-fat diet. Quercetin 4′-glucoside (50%), free quercetin (30%) and quercetin 3,4′-diglucoside (20%) were identified as quercetin derivatives, and boiling-water extraction was effective in extracting these compounds. OP contained 12.9% of polyuronides, the basic skeleton of pectin. Enzymatic degradation (cellulase and pectinase, 50 °C for 12 h, pH 6.0) of OP was effective in obtaining a slurry of smaller particle sizes. The free quercetin increased and the glucosides decreased with enzyme treatment. In Wistar rats fed an OP-added high-fat diet, the total cholesterol, HDL-cholesterol and triglyceride concentrations were not significantly different from the rats fed a high-fat diet without OP. However, the atherogenic index (AI) of Wistar rats fed an OP-added high-fat diet was lower (AI = 3.3) than rats fed the diet without OP (AI = 4.1). The incremental elastic modulus (IEM) of the aorta from rats fed the OP-added diet was also significantly lower than that of the rats fed the diet without OP. The AI and IEM values of the rats fed the OP-added diet were quite similar to the values of rats fed the diet without OP but were allowed spontaneous exercise. These results suggest that OP intake is effective for decreasing the risk of arteriosclerosis.     

Suppressed Lattice Disorder for Large Emission Enhancement and Structural Robustness in Hybrid Lead Iodide Perovskite Discovered by High-Pressure Isotope Effect

The soft nature of organic–inorganic halide perovskites renders their lattice particularly tunable to external stimuli such as pressure, undoubtedly offering an effective way to modify their structure for extraordinary optoelectronic properties. Here, using the methylammonium lead iodide as a representative exploratory platform, it is observed that the pressure-driven lattice disorder can be significantly suppressed via hydrogen isotope effect, which is crucial for better optical and mechanical properties previously unattainable. By a comprehensive in situ neutron/synchrotron-based analysis and optical characterizations, a remarkable photoluminescence (PL) enhancement by threefold is convinced in deuterated CD₃ND₃PbI₃, which also shows much greater structural robustness with retainable PL after high peak-pressure compression–decompression cycle. With the first-principles calculations, an atomic level understanding of the strong correlation among the organic sublattice and lead iodide octahedral framework and structural photonics is proposed, where the less dynamic CD₃ND₃⁺ cations are vital to maintain the long-range crystalline order through steric and Coulombic interactions. These results also show that CD₃ND₃PbI₃-based solar cell has comparable photovoltaic performance as CH₃NH₃PbI₃-based device but exhibits considerably slower degradation behavior, thus representing a paradigm by suggesting isotope-functionalized perovskite materials for better materials-by-design and more stable photovoltaic application.     

Effect of Oxygen on the Self-formation of Carbonaceous Tribo-layer with Carbon Nitride Coatings under a Nitrogen Atmosphere

The ball-on-disk friction and wear tests of CN _X coatings (CN _X /CN _X ) were conducted under a nitrogen atmosphere with controlled relative humidity (RH) (3.4–40.0%RH) and oxygen concentration (100–21 × 10⁴ ppm) in this study. We found that the specific wear rate of CN _X coating on ball (W _b), which could give stable and low friction coefficient (<0.05), was below 3.0 × 10^?8 mm³/Nm. Average friction coefficients (µ _a) and W _b of CN _X /CN _X increased (µ _a: 0.02–0.33, W _b: 1.6 × 10^?8–2.4 × 10^?7 mm³/Nm) with increasing oxygen concentration (230–211,000 ppm) as well as RH (4.7–21.1%RH) under a nitrogen atmosphere. However, the W _b remained low value below 2.3 × 10^?8 mm³/Nm regardless of oxygen concentration (100–207,000 ppm) of a nitrogen atmosphere (3.4–3.9%RH) when CN _X -coated balls were slid against a hydrogenated CN _X (CN _X :H) coatings (CN _X /CN _X :H). Besides, the CN _X /CN _X :H achieved low and stable friction coefficient below 0.05 under a nitrogen atmosphere (10,000 ppmO₂) regardless of increasing RH up to 20%RH. Raman analysis indicated that the structure of carbon on the top surface of CN _X coating was changed from as-deposited CN _X coating in the case of low friction coefficient (<0.05). Furthermore, TOF-SIMS analysis provided the evidence that the carbon derived from CN _X -coated disk was considered to diffuse into the ball surface, and it mixed with the carbon derived from CN _X -coated ball on the wear scar, which formed the chemically bonded carbon tribo-layer. Low friction coefficient (<0.05) with CN _X coatings under a nitrogen atmosphere was achieved due to self-formation of the carbon tribo-layer.     

An analysis of the spillover effects based on patents and inter-industrial transactions for an emerging blockchain technology

Scientometrics - A simple and robust approach to predict the spillover effects of emerging technologies enables proper formulation of investment strategies. In this study, we propose the method in...     

Poly(N‐isopropylacrylamide) gel‐based macroporous monolith for continuous‐flow recovery of palladium(II) ions

Macroporous monoliths, composed of thermoresponsive, tertiary‐aminated, and crosslinking monomers, were prepared for continuous‐flow separation of palladium(II) ions. N ‐Isopropylacrylamide was required to form the porous structure in the monoliths, indicating that the mechanism of porous structure formation involved polymerization‐induced phase separation of the poly(N ‐isopropylacrylamide) gel. Tertiary‐aminated monoliths showed adsorption selectivity for palladium(II) ions in hydrochloric media, compared with copper(II) ions. The maximum capacities of the monoliths with tertiary amine contents of 10, 20, 30, and 70 mol % for palladium(II) ions were 0.6, 1.1, 1.3, and 2.3 mmol/g, respectively. Darcy's permeabilities of water through the macroporous monolith were 10^?14 to 10^?13 m², and those were comparable to that through a commercially available membrane filter with a pore size of several micrometers. In the continuous‐flow process, the macroporous monolith with tertiary amine selectively adsorbed palladium(II) ions in the coexistence of copper(II) ions with 10 times higher concentration than the palladium(II) ions. The palladium(II) ions were eluted from the macroporous monolith, and the concentration of palladium(II) ions in the eluate was up to 45 times of that in the feed solution. The average enrichment factor and total recovery percentage of palladium(II) ions were 8.7 times and 95%, respectively. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44385.     

Structure and Thermophysical Properties of Molten BaGe Using Electrostatic Levitation Technique

BaGe alloys with two compositions near their eutectic point form open framework structures called the clathrate structure. These BaGe compounds with the clathrate structure can be made by rapid solidification from their liquid state. However, the formation mechanism of the clathrate structure has not been clarified due to lack of information on their liquid-state structure and properties. Since BaGe alloy melts have very high reactivity, it is difficult to measure the thermophysical properties of them by ordinary methods using a container. Therefore, a containerless technique must be used to measure the thermophysical properties of BaGe melts. Using the electrostatic levitation (ESL) technique as a containerless technique, the thermophysical properties (density, surface tension, and viscosity) of BaGe melts around the eutectic composition were measured in order to clarify the formation mechanism of the clathrate structure, and also the structure of them was observed by using the high-energy X-ray diffraction method combined with ESL. From experimental results, it was observed that the short-range order based on the clathrate structure exists even in the liquid state at the clathrate-forming compositions.     

Theoretical study of the adsorption of Cs,Cs+, I,I−, and CsI on C60 fullerene

Theoretical investigation for the adsorption of the cesium atom (Cs), the cesium iodide molecule (CsI), the iodine atom (I), the cesium cation (Cs⁺), and the iodide anion (I^?) onto the surface of a single fullerene molecule (C₆₀) are reported. A hybrid exchange–correlation functional using the Coulomb-attenuating method (CAM-B3LYP) is employed. The adsorption energies, i.e., the opposite of enthalpy change through adsorption, are calculated to be 143, 12, 9, 46, and 49 kJ mol^?1 for Cs, CsI, I, Cs⁺, and I^?, respectively. The equilibrium constant for Cs is calculated to be 7×10³ atm^?1 at the temperature of 1000 K and is seven orders of magnitude higher than that for CsI, indicating that the C₆₀ molecule adsorb the Cs atom highly selectively against the CsI molecule.