Fabrication of In2O3/In2S3 heterostructures for enhanced photoelectrochemical performance

Constructing core/shell heterojunction has always been an effective strategy for photoelectrochemical (PEC) water splitting owing to special morphology characterization and band structure. Herein, we synthesized a series of In₂O₃/In₂S₃ core/shell structure photoanodes via a simple two-step hydrothermal method to improve the PEC performance of In₂O₃. Various methods were employed to investigate the influence of sulfurization time on the morphologies, microstructures, photoelectrochemical properties and band structures of the as-prepared photoanodes. The results indicated that the In₂O₃/In₂S₃-5 possessed stronger visible light absorption, faster charge transfer rate and higher electron carrier density, which resulted in an excellent PEC performance. Under visible light irradiation, the photocurrent density of the In₂O₃/In₂S₃-5 photoanode reached 0.53 mA cm⁻² at 1.23 V vs RHE in 1 M NaOH solution, which was about twice as high as that of the pristine In₂O₃. Furthermore, the onset potential of the In₂O₃/In₂S₃-5 photoanode had an obvious negative shift (~200 mV) when compared to the pure In₂O₃ nanorod photoanode.     

A new atomistic model for the threading screw dislocation core in wurtzite GaN

We report a new atomistic model for the threading screw dislocation core in wurtzite gallium nitride. By combining elasticity theory and atomistic simulations, we have revealed the new core configuration, with a double 6-atoms ring structure, to be more energetically favourable than the previously known one with a single 6-atoms ring structure, introduced about ten years ago. The new core configuration is fully coordinated and has both Ga-Ga and N-N homo-nuclear bonds in its centre. As the double 6-atoms ring core is free from dangling bonds, it was found to introduce less dispersed energy levels in the bandgap than the single 6-atoms ring core.     

Hydrodynamics of lube oil–water flow through 180° return bends

In the present work, the hydrodynamics of high viscous oil–water flow through return bends have been studied. Two bend geometries (U and rectangular) and three flow directions through the bend (up, down and horizontal flow) are considered. It is noted that the direction of flow of two-phase mixture through the bend has a significant influence on the downstream phase distribution while the bend geometry has a negligible influence on the same. The pressure drop is higher across the rectangular bend as expected and the loss coefficients are independent of flow patterns in all the cases.     

Fe-based amorphous soft magnetic composites with SiO2 insulation coatings: A study on coatings thickness,microstructure and magnetic properties

Core-shell structured FeSiBCCr@SiO₂ amorphous soft magnetic composites (ASMCs) with tunable insulating layer thicknesses have been designed and fabricated by the powder metallurgy method. The growth process of the coatings obtained via the sol-gel method has been systematically studied based on the analysis of the growth mechanism and the insulating layer thicknesses calculated by a modified method. In the powder-coating process using small quantities of tetraethyl orthosilicate (TEOS) (0.025–0.1 mL/g), a relatively uniform insulating layer is formed on the surface of the powders. Increasing the TEOS concentration further (0.25–1 mL/g) greatly enhances the reaction kinetics of the hydrolysis and condensation reactions. Consequently, the SiO₂ shells of the amorphous powder rapidly grow in thickness and also generate aggregates. The evolution of the thickness of the coatings under different growth conditions also corresponds to the variation of the magnetic performance of the ASMCs. The ASMCs with an appropriate SiO₂ insulating layer exhibit stability at high frequencies and significantly lower the contribution of eddy current to the total loss. Conversely, a thick insulation layer results in a high fraction of the non-magnetic phase and consequently enhances the hysteresis loss. Thus, an enhanced magnetic performance of the FeSiBCCr ASMCs can be achieved by adjusting the TEOS concentration (0.025–0.1 mL/g) or the thickness of the SiO₂ insulating layer.     

Conceptual design of long-cycle boron-free small modular pressurized water reactor with control rod operation

This paper presents a new conceptual design of soluble-boron-free small modular pressurized water reactor (SMPWR) core with the following singular features: long operation cycle, axially heterogeneous adjuster control rods, and ring-type burnable absorbers (R-BAs) coated on the outside of cladding materials. The core loads 37 Westinghouse-type 17 × 17 fuel assemblies (FAs) of active fuel height 200 cm and produces 180 MW of nominal thermal power during a cycle length of 1555 effective full power days (EFPDs). Three types of burnable absorbers (BAs) are used to address the excess reactivity and obtain a long cycle: 2 w/o and 8 w/o enriched Gd₂O₃ integral-type BA (IBA), natural gadolinium R-BA, and 80 w/o enriched ¹⁰B Al₂O₃/B₄C wet annular burnable absorber (WABA). Two types of 200 cm long axially heterogeneous adjuster control rods are used to control the reactivity and the offset in axial power distribution. The first rod type adopts HfB₂ with 80 w/o enriched ¹⁰B for the bottom 140 cm and stainless steel for the top 60 cm. The second rod type uses HfB₂ (natural boron) for the bottom 100 cm and HfB₂ (80 w/o enriched ¹⁰B) for the top 100 cm. A detailed safety parameter analysis is conducted to verify the imposed design limits, namely, axial shape index of less than ±0.4, 3D power peaking factor of smaller than 5.09, required shutdown margin of greater than 3000 pcm, and negative isothermal temperature coefficient during the entire reactor operation. It is successfully demonstrated that the proposed novel SMPWR design satisfies all the design limits and the target cycle length of 1500 EFPDs.     

Hydroconversion of Waste Cooking Oil into Bio‐Jet Fuel over a Hierarchical NiMo/USY@Al‐SBA‐15 Zeolite

The direct conversion of waste cooking oil (WCO) into bio‐jet fuel was investigated over a core‐shell hierarchical USY@Al‐SBA‐15 zeolite‐supported NiMo catalyst. The core‐shell structure showed better acid and pore size distributions. The synergetic effect of the core‐shell micropore and mesopore structure significantly contributed to enhancing the selectivity for the jet fuel (C_9–15 hydrocarbons) from 9.3 % over NiMo/USY up to 35.7 % over NiMo/USY@Al‐SBA‐15, with high isomerization (iso‐/n‐paraffins ratio = 2.7) and moderate aromatic fraction (18.7 %). The decarboxylation reaction was selectively enhanced. Optimal selectivity for jet fuel (39.7 %) was obtained at 380 °C and a high H₂/oil ratio would decrease the yield of jet fuel. This catalyst showed excellent stability for the hydroconversion of WCO to hydrocarbons.     

What has debt got to do with it? The Valuation of Homeownership in the Era of Financialization

Based on comparative focus group data from Norway, Denmark and England, this article asks why people take on substantial mortgages to become homeowners. It argues that financialization of the housing market has resulted in a widespread investment philosophy at the household level and changed the way people think and talk about “the home”. High levels of mortgage borrowing have become commonplace and are justified by social valuations of owner-occupation based on beliefs around freedom through homeownership. Like previous research, the study shows that homeownership offers social identity, stability and belonging. But, this is wrapped up in an investor’s language, such that the distinction between homes as socially valued living environments and homes as investment objects has become blurred. This makes it difficult – perhaps impossible – for households to assess the risks involved in home purchases.     

Synthesis of CoAl2O4/Al2O3 nanoparticles for ceramic blue pigments

The demand for pigments for industrial ceramic ink-jet printing is increasing steadily. The main challenge is the availability of ceramic pigments comprised of small-sized particles in order to avoid clogging of the printer head nozzle. This work presents a novel way to prepare ceramic blue pigment as a shell/core structure of CoAl₂O₄/Al₂O₃ nanoparticles through a simple and low-cost process. In this process, the colour tone of nano-pigment can be tuned by the selection of the cobalt precursor/Al₂O₃ ratio and calcining temperature.     

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