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The structural and superconducting properties of alkali-Bi-based compounds, KBi2 and RbBi2, were investigated over a wide pressure range for the first time.

Laying-down gold nanorods (GNRs) of a monolayer immobilized on a solid substrate was realized with a hybrid method, a combination of three elemental technologies: surface modification, electrophoresis, and solvent evaporation. The self-assembly of CTAB-protected GNRs in the solution was induced by 0.05 mM of EDTA. The assembled GNRs were deposited in a laying-down form on the solid surface during the hybrid method. The final coverage was over 71% on the substrate with an area larger than 0.6 cm2. The spacing between the sides of the GNRs was fixed to be 4.6 ± 0.9 nm by the thermal annealing-promoted crystalline packing of the bilayer of CTAB salt-bridged with EDTA. The obtained laying-down GNRs of a monolayer on the gold substrate show a small shift of the transverse LSPR around 550-570 nm (with a width of around 100 nm) and a large red shift of the longitudinal LSPR to be 900-1050 nm (with a width of 500 nm), because of the strong electromagnetic coupling between the GNRs and gold substrate. Therefore it can be used in a wide range of wavelengths for surface enhanced Raman spectroscopy (SERS) applications. The film has a high enhancement factor with 105 for R6G.

A superconducting KBi2 sample was successfully prepared using a liquid ammonia (NH3) technique. The temperature dependence of the magnetic susceptibility (M/H) showed a superconducting transition temperature (Tc) as high as 3.6 K. In addition, the shielding fraction at 2.0 K was evaluated to be 87%, i.e., a bulk superconductor was realized using the above method. The Tc value was the same as that reported for the KBi2 sample prepared using a high-temperature annealing method. An X-ray diffraction pattern measured based on the synchrotron X-ray radiation was analyzed using the Rietveld method, with a lattice constant, a, of 9.5010(1) A under the space group of Fd[3 with combining macron]m (face-centered cubic, no. 227). The lattice constant and space group found for the KBi2 sample using a liquid NH3 technique were the same as those reported for KBi2 through a high-temperature annealing method. Thus, the superconducting behavior and crystal structure of the KBi2 sample obtained in this study are almost the same as those for the KBi2 sample reported previously. Strictly speaking, the magnetic behavior of the superconductivity was different from that of a KBi2 sample reported previously, i.e., the KBi2 sample prepared using a liquid NH3 technique was a type-II like superconductor, contrary to that prepared using a high-temperature annealing method, the reason for which is fully discussed. These results indicate that the liquid NH3 technique is effective and simple for the preparation of a superconducting KBi2. In addition, the topological nature of the superconductivity for KBi2 was not confirmed.

Herein, we report the preparation and characterization of BaBi

The crystal structures of Sb

We investigated the pressure dependence of electric transport in a superconducting sample, Ba

Electronic devices relying on the combination of different conjugated organic materials are considerably appealing for their potential use in many applications such as photovoltaics, light emission, and digital/analog circuitry. In this study, the electrical response of field-effect transistors achieved through the evaporation of picene and PDIF-CN

A new superconducting sample, BaTi2Bi2O, was synthesized and characterized over a wide pressure range. The superconducting transition temperature, Tc, of BaTi2Bi2O was 4.33 K at ambient pressure. The crystal structure was tetragonal (space group of P4/mmm (No. 123)), according to the X-ray diffraction (XRD) pattern at ambient pressure. The XRD pattern was analyzed using the Le Bail method. The magnetic-field dependence of the magnetization at different temperatures was precisely investigated to elucidate the characteristics of the superconductivity. The pressure-dependent XRD patterns showed absence of structural phase transitions up to 19.8 GPa. The superconducting properties of BaTi2Bi2O were investigated under pressure. Tc monotonously increased with the pressure (p) up to 4.0 GPa and saturated above 4.0 GPa. The variations in the Tc-p plot were thoroughly analyzed. The Cooper pair symmetry (or superconducting pairing mechanism) was analyzed based on the magnetic field dependence of the superconductivity at ambient and high pressures, which indicated a sign of p-wave pairing for the superconductivity of BaTi2Bi2O, i.e., topologically nontrivial sign was suggested for BaTi2Bi2O.

A superconducting KBi

This study investigates the effect of high dissolved oxygen concentrations (DO) on sterlet Acipenser ruthenus maturation. Two groups, each comprising 246 individuals of 8-month-old juvenile sterlets, were reared for 37 months under high DO (group H, mean DO of 11.2 mg/L) or normal DO (group C, mean DO of 7.3 mg/L). Significant differences in body weight were observed between group H (638.7 ± 191.9 g) and group C (572.2 ± 151.9 g) in 12 months (P 0.05) in 24 months. Significant differences in follicle diameter in mature females were also observed. Group H included 68 mature females, with an average follicle diameter of 2318.0 ± 175.3 µm, whereas group C included 56 mature females, with a smaller average follicle diameter of 2152.3 ± 287.0 µm (P

A reflective shuttling detention combustor (RSDC) is a two-dimensional combustor with two reflection walls. Unlike a rotating detonation combustor (RDC), an RSDC can visualize the entire area of the combustor via an optical technique. In addition, the RSDC can reproduce the counter-rotating detonation mode in RDC. In present study, CH* luminescence and schlieren image were observed to investigate the dynamics of the RSDC. The reflective wall distance was set to 45 mm (Type L) and 25 mm (Type S). As the results, the wave speed of 1226 ± 64 m / s in the single wave mode in Type S was 76% of that in Type L. It was found that the detonation propagation speed decreased with a reduction in the reflection wall distance. Superimposing the luminescence images on the schlieren images revealed that the mixture was mainly burned by deflagration behind shock wave. In addition, the experimental mixture fill height was in good agreement with model in which the mixture filling process was temporarily stopped by detonation and refilled at a constant speed. Using the maximum fill height obtained by the model, it was found that the detonation mode was in the region of 3 ± 0.6 of the dimensionless quantity (the reflection wall distance divided by the wave number and maximum value of the mixture fill height).

Titania (TiO 2 ) films in which silica (SiO 2 ) nanoparticles are embedded (SiO 2 /TiO 2 films) are prepared by a combination of a novel aerosolization technique and plasma-enhanced chemical vapor deposition (PECVD). Using titanium tetraisopropoxide (TTIP) in a microwave plasma field, anatase films are prepared on silicon and quartz-glass substrates. By utilizing Coulomb explosion of charged droplets in the plasma field, an aerosol with well-dispersed SiO 2 nanoparticles is obtained from the breakup of sprayed droplets of a nanoparticle suspension. Simultaneous feeding of the TTIP vapor as a gaseous raw material and the SiO 2 nanoparticle aerosol as a solid raw material enables preparation of the SiO 2 /TiO 2 films with many protrusions. The number and size of the protrusions increase with increasing concentration of the nanoparticle suspension and increasing size of the nanoparticles, respectively. The size of the nanoparticles is related to the surface roughness of the SiO 2 /TiO 2 films. Quantitative evaluation of the protrusions suggests that the mechanism of the protrusion evolution on SiO 2 nanoparticles varies with the size of the nanoparticles. Embedding SiO 2 nanoparticles into the TiO 2 films enhances the photocatalytic activities compared to that of a TiO 2 -only film probably because the protrusions increase the surface area of the films.

The self-assembled monolayer (SAM)-modified metallic nanoparticles (MNPs) often exhibit improved chemoselectivity in various catalytic reactions by controlling the reactants&rsquo, orientations adsorbed in the SAM, however, there have been a few examples showing that the reaction rate, i.e., catalytic activity, is enhanced by the SAM-modification of MNP catalysts. The critical parameters that affect the catalytic activity, such as the supports, nanoparticle size, and molecular structures of the SAM components, remain uninvestigated in these sporadic literature precedents. Here, we report the mechanistic investigation on the effects of those parameters on the catalytic activity of alkanethiolate SAM-functionalized gold nanoparticles (AuNPs) toward silane alcoholysis reactions. The evaluation of the catalytic reaction over two-dimensionally arrayed dodecanethiolate SAM-functionalized AuNPs with different supports revealed the electronic interactions between AuNPs and the supports contributing to the rate enhancement. Additionally, an unprecedented size effect appeared&mdash, the AuNP with a 20 nm radius showed higher catalytic activity than those at 10 and 40 nm. Infrared reflection&ndash, absorption spectroscopy revealed that the conformational change of alkyl chains of the SAM affects the entrapment of reactants and products inside the SAM, and therefore brings about the acceleration effect. These findings provide a guideline for further applying the SAM-functionalization technique to stereoselective organic transformations with designer MNP catalysts.

An unprecedented substrate-selective catalytic enhancement effect of an alkanethiol-self-assembled monolayer (SAM) on Au nanoparticles (AuNPs) is reported. In the supported 2D-array of AuNPs, the alkanethiol-SAM acts as a protein-like soft reaction space in which the substrate molecules are encapsulated through non-covalent intermolecular hydrophobic interactions, and thus catalytic reactions are accelerated at AuNP surfaces.

Innovative nanophotonic applications require a technique for generating not a nanometer-scale point but a large-area (mm2−m2) near-field light source. We succeeded in developing a large-area near-field light source that is densely constructed of uniform-size gold nanoparticles (AuNPs) two-dimensionally arrayed with regular interparticle gaps, which has tunable localized surface plasmon resonance bands (600–1100 nm). The near-field excitation properties based on the optical tunability of the AuNP two-dimensional arrays demonstrate that our chemical coating of large-area near-field light sources is widely applicable such as for high-sensitivity optical sensors and high-efficiency solar cells.