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To understand the influence of doping Sr atoms on the structural, magnetic, and electronic properties of the infinite-layer NdSrNiO2, we carried out the screened hybrid density functional study on the Nd9-nSrnNi9O18 (n = 0–2) unit cells. Geometries, substitution energies, magnetic moments, spin densities, atom- and lm-projected partial density of states (PDOS), spin-polarized band structures, and the average Bader charges were studied. It showed that the total magnetic moments of the Nd9Ni9O18 and Nd8SrNi9O18 unit cells are 37.4 and 24.9 emu g−1, respectively. They are decreased to 12.6 and 4.2 emu g−1 for the Nd7Sr2Ni9O18-Dia and Nd7Sr2Ni9O18-Par unit cells. The spin density distributions demonstrated that magnetic disordering of the Ni atoms results in the magnetism decrease. The spin-polarized band structures indicated that the symmetry of the spin-up and spin-down energy bands around the Fermi levels also influence the total magnetic moments. Atom- and lm-projected PDOS as well as the band structures revealed that Ni (d x 2 − y 2 ) is the main orbital intersecting the Fermi level. As a whole, electrons of Sr atoms tend to locate locally and hybridize weakly with the O atoms. They primarily help to build the infinite-layer structures, and influence the electronic structure near the Fermi level indirectly. [ABSTRACT FROM AUTHOR]

A new type of imitation rattan was developed via a two-step method that used modified wheat straw as the raw materials and low-density polyethylene to make up wood plastic composite. Post-modification, a graft condensation reaction was carried out between silane as a coupling agent and wheat straw powder, which improved the thermal stability of the composite. A high level of contact and interaction at the fibre-matrix interface was observed. The optimum formula for the first step was 80% wheat straw powder, 4% silane coupling agent, and 16% calcium carbonate, with a modification temperature of 120 °C sustained for 10 min. For the second step, the mechanical properties had been greatly improved with the addition of modified wheat straw fibre and maleic anhydride grafted polypropylene (MA-g-PP). The use of 10% modified straw fibre and 5% MA-g-PP exhibited the highest tensile strength (8.75 MPa) and highest melt index (2.86 g/10 min). In particular, the MA-g-PP had an extremely advantage to the elastic modulus of wheat straw imitation rattan. The elastic modulus reached the maximum value of 2761.70 MPa at the amount of MA-g-PP added reached 5%. Our present study indicated the innovation of a new type of imitation rattan, which provides a new choice for utilizing wheat straw as industrial raw material, and other agricultural by-products containing liginocellulose could be used in a similar way. [ABSTRACT FROM AUTHOR]

Measurements of sub-3 nm particles are technically challenging and characterized with significant uncertainties. This study selected two types of widely used commercial instruments: an Airmodus® Particle Size Magnifier (PSM) and a TSI® diethylene glycol-based Scanning Mobility Particle Sizer (DEG–SMPS), and examined factors that govern their abilities on measurements of sub-3 nm particles. Monodisperse standard particles used in the experiments include positively and negatively charged tungsten oxide particles and nickel–chromium (Ni/Cr) oxide particles, positive and negative ions produced in a soft X-ray neutralizer, and positively charged organic particles including tetraheptylammonium bromide (THABr), tetrabutylammonium bromide (TBABr), and polyethylene glycol (PEG) particles. Our results show that both PSM and DEG–SMPS are subject to the influence of particle composition. Negatively charged tungsten oxide particles were detected at higher efficiencies than positively charged ones, whereas opposite results were observed for Ni/Cr particles and background ions produced in the soft X-ray neutralizer. In addition, the concentration accuracy of PSM and DEG–SMPS are explored after calibration using Ni/Cr particles. The inverted total concentrations by DEG–SMPS are usually underestimated because of the overestimation of penetration efficiency through different modules, whereas the inverted total concentrations by PSM can be either overestimated or underestimated, when the properties of analyte particles are significantly different from the calibration particles. A better understanding on the effects of particle chemical composition and charging state, and their diffusion losses in the instruments will help to diminish the uncertainties in the measurements. Copyright © 2022 American Association for Aerosol Research. [ABSTRACT FROM AUTHOR]