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X-ray diffraction, magnetic susceptibility, magnetization, heat capacity and electrical resistivity results are reported for single crystals of two structural variants of EuNi2-δSb2that crystallize in the CaBe2Ge2and ThCr2Si2-type structures. While the former occurs with a stoichiometric ratio, the latter exhibits a Ni site vacancy (δ = 0.36). Both systems exhibit similar magnetic behavior at elevated temperatures, where there is an isotropic Curie-Weiss temperature dependence that indicates an antiferromagnetic exchange interaction between divalent europium ions, although it is stronger for the CaBe2Ge2-variant. At low temperatures, the differing structural environments that surround the Eu ions result in distinct ordering behavior. The CaBe2Ge2-variant orders antiferromagnetically nearTN1= 6.9 K and then undergoes a first order phase transition atTM= 4.6 K. The ThCr2Si2-variant exhibits simpler behavior, with antiferromagnetic ordering atTN2= 5.6 K. For both compounds, an applied magnetic field suppresses the ordering temperatures and induce metamagnetic phase transitions, while applied pressure causes the ordering temperatures to increase. From these results, EuNi2-δSb2emerges as a useful system in which to study the impact of structural variation on magnetism in a Eu-based metal. © 2020 IOP Publishing Ltd.The propagation of sidewall steps during the growth of nanowires is calculated in the frame of the Burton-Cabrera-Frank model. The stable shape of the nanowire comprises a cylinder section on top of a cone section their characteristics are obtained as a function of the radius of the catalyst-nanowire area, the desorption-limited diffusion length of adatoms on the terraces, and the sticking of adatoms at step edges. The comparison with experimental data allows us to evaluate these last two parameters for InP and ZnTe nanowires; it reveals a different behavior for the two materials, related to a difference by an order of magnitude of the desorption-limited diffusion length. © 2020 IOP Publishing Ltd.In this study, we developed a procedure for assembling hepatic microstructures into tube shapes using magnetic self-assembly for in vitro 3D micro-tissue fabrication. To this end, biocompatible hydrogels, which have a toroidal shape, were made using the micro-patterned electrodeposition method. Ferrite particles were used to coat the fabricated toroidal hydrogel microcapsules using a poly-L-lysine (PLL) membrane. The microcapsules were then magnetized with a 3T magnetic field, and assembled using a magnetic self-assembly process. During electrodeposition, hepatic cells were trapped inside the microcapsules, and they were cultured to construct tissue-like structures. The magnetized toroidal microstructures then automatically assembled to form tube structures. Shaking was used to enhance the assembly process, and the shaking speed was experimentally optimized to achieve the high-speed assembly of longer tube structures. The flow velocity inside the dish during shaking was measured by particle image velocimetry (PIV). Hepatic functions were evaluated to check for side-effects of the magnetized ferrite particles on the microstructures. Collectively, our findings indicated that the developed method can achieve the high-speed assembly of a large number of microstructures to form tissue-like hepatic structures. © 2020 IOP Publishing Ltd.Fe3O4 nanoparticles (NPs) with different shapes have been prepared by a 'solventless' synthesis approach to probe shape anisotropy effects on the magnetic and inductive heating properties. Various shapes including spheres, octahedrons, cubes, rods, wires, and multipods are obtained through alterations in reaction conditions such as the precursor to surfactant content and heating rate. Magnetic and Mössbauer measurements reveal better stoichiometry in anisotropic-shaped Fe3O4 NPs than that in the spherical and multipod NPs. As a result, the magnetization value of the anisotropic-shaped NPs approaches the value for bulk material (~ 86 emu/g). More surprisingly, the Verwey transition, which is a characteristic phase transition of bulk magnetite structure, is observed near 120 K in the anisotropic-shaped NPs, which further corroborates the fact that these NPs possess better stoichiometry compared to the spherical and multipod-shaped NPs. Other than the improved magnetic properties, these anisotropic-shaped NPs are more effective for hyperthermia applications. For example, compared to the conventional spherical NPs, the nanowires show much higher SAR value up to 846 W/g, making them a potential candidate for practical hyperthermia treatment. © 2020 IOP Publishing Ltd.Although there are numerous virtues for lithium sulfur batteries, the notorious shuttle effect and insulated nature are impeding their practical application. To address these issues, here we report the design and synthesis of polypyrrole coated sulfur and cobalt co-doped carbon nanocages (PSCC). It demonstrates that both the performance and stability of the PSCC assisted Li-S batteries are improved. The hollow structure of PSCC bypassed the structural collapse effectively caused by volume expansion of sulfur during the reaction and physically suppressed shuttle effect of the intermediate product polysulfide lithium (LiPSs). What's more, LiPSs was also trapped to inhibit the shuttle effect due to the strong adsorption of LiPSs via PSCC. In addition, PSCC can also provide an outstanding electronic conductivity, which will facilitate the next-step reaction of the absorbed LiPSs and enhance electrochemical reaction kinetics. Thus, the excellent rate performance was obtained with high specific discharge capacities of 1300 mAh/g at 0.1 C and 1000 mAh/g at 0.5 C. Such packaged high-performance positions our design for the ideal electrochemical energy storage devices. © 2020 IOP Publishing Ltd.Detailed powder neutron diffraction studies as a function of temperature is performed on NdFe0.5Mn0.5O3in the temperature range 400 - 1.5 K. Diffused magnetic scattering is observed due to three dimensional short-range ordering (SRO), between Fe3+/Mn3+spins, over the whole temperature range 400 - 1.5 K. The presence of SRO is independent of long-range ordering (LRO) in this compound which has never been observed in any Fe3+/Mn3+based compounds. Further, in this compound two-fold spin reorientation is discussed in the temperature range 300 - 1.5 K. Development of long-range ordering at 300 K is due to the mixture ofΓ4andΓ1magnetic structure, not like other orthoferrites which haveΓ4structure at 300 K. This occurs due to the presence of large single-ion anisotropy of Mn3+ions. Volume fraction ofΓ4decreases with temperature leading to pureΓ1magnetic structure in the temperature range 150 - 90 K. Another spin reorientation of Fe3+/Mn3+ spins occurs fromΓ1toΓ2in the temperature range 70 - 25 K. © 2020 IOP Publishing Ltd.Absorption of visible light and separation of photogenerated charges are two primary pathways to improve the photocurrent performance of semiconductor photoelectrodes. Here, we present a unique design of tricomponent photocatalyst comprising of TiO2 multileg nanotubes (MLNTs), reduced graphene oxide (rGO) and CdS nanoparticles. The tricomponent photocatalyst shows a significant red-shift in the optical absorption (~ 2.2 eV) compared to that of bare TiO2 MLNTs (~ 3.2 eV).The availability of the both inner and outer surfaces areas of MLNTs, visible light absorption of CdS, and charge separating behavior of reduced graphene oxide layers contribute coherently to yield a photocurrent density of ~11 mA/cm2 @ 0 V vs. Ag/Cl (100 mW/cm2, AM 1.5 G). Such a high PEC performance from TiO2/rGO/CdS photoelectrode system has been analyzed using diffused reflectance (DRS) and electrochemical impedance (EIS) spectroscopy techniques. The efficient generation of charge carriers under light irradiation and easy separation because of favourable band alignment are attributed to the high photoelectrochemical current density in these tricomponent photocatalyst system. © 2020 IOP Publishing Ltd.In this study, amorphous cobalt hydroxide/polyaniline nanofibers (Co(OH)2/PANINF) composites were successfully prepared. The formation of amorphous Co(OH)2with irregular surface structure was confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and selected area electron diffraction (SAED). The non-enzymatic electrochemical sensor for the selective and sensitive determination of dopamine (DA) has been constructed by using Co(OH)2/PANINF composites modified glassy carbon electrode (Co(OH)2/PANINF/GCE), which exhibited excellent electrocatalytic activity toward DA, in a large part owing to the advantages of large surface area of amorphous Co(OH)2and the synergetic effect between Co(OH)2and PANINF. The electrochemical kinetics reveal that the DA oxidation involves two electrons and two protons in a quasi-reversible electrode reaction. Differential pulse voltammetry (DPV) studies show remarkable sensing performance for the determination of DA, with a low detection limit of 0.03μM, and a wide linear range from 0.1 to 200 μM. From a broader perspective, the present study demonstrates that Co(OH)2/PANINF composites would be promising supporting materials for novel sensing platforms. NG25 nmr © 2020 IOP Publishing Ltd.We study theoretically proximity-induced superconductivity and its inverse effect in dice lattice flat band model by considering Josephson junction with an s-wave pairing in the superconducting leads. Using self-consistent tight-binding Bogoliubov-de Gennes method, we show that there is a critical value for chemical potential of the superconductors depending on paring interaction strength over which for undoped normal region the proximity effect is enhanced. Whereas if the superconductor chemical potential is less than the critical one the proximity effect decreases regardless of normal region doping and in the meanwhile, the pairing amplitude of superconducting region increases significantly. Furthermore, we unveil that the supercurrent passing through the junction is large (vanishingly small) when the superconductor chemical potential is smaller (larger) than the critical value which increases as a function of normal region chemical potential. © 2020 IOP Publishing Ltd.This paper introduces the concept of continuous chaotic printing, i.e., the use of chaotic flows for deterministic and continuous extrusion of fibers with internal multilayered micro- or nanostructures. Two free-flowing materials are coextruded through a printhead containing a miniaturized Kenics static mixer (KSM) composed of multiple helicoidal elements. This produces a fiber with a well-defined internal multilayer microarchitecture at high-throughput (>1.0 m min-1). The number of mixing elements and the printhead diameter determine the number and thickness of the internal lamellae, which are generated according to successive bifurcations that yield a vast amount of inter-material surface area (~102cm2cm-3) at high resolution (~10 µm). This creates a new opportunity to produce structures with extremely high surface area to volume (SAV). Comparison of experimental and computational results demonstrates that continuous chaotic 3D printing is a robust process with predictable output. In an exciting new development, we demonstrate a method for scaling down these microstructures by 3 orders of magnitude, to the nanoscale level (~150 nm), by feeding the output of a continuous chaotic 3D printhead into an electrospinner.