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Summary: Accurate evaluation of metal bioavailability to hyperaccumulators is necessary for prediction of metal uptake and estimation of phytoextraction potential. Sedum plumbizincicola X.H. Guo et S.B. Zhou ex L.H. Wu (Crassulaceae), a hyperaccumulator of cadmium (Cd) and zinc (Zn), was grown in a pot experiment in 108 agricultural soils representing a wide range of typical Chinese soil types. The contribution of soil properties to Zn uptake was assessed quantitatively. Soil total Zn, soluble Zn, CaCl2‐extractable Zn and (DGT)‐extractable Zn concentrations (Zntotal, Znsoln, ZnCaCl2 and ZnDGT, respectively) were compared to predict shoot Zn concentration (Znshoot) using a piecewise equation. This showed a logarithmic increase with increasing Zntotal from 100–1000 mg kg−1 but plateaued outside this range. The optimum soil pH for Zn removal was ~ 5.5 and further acidification was unnecessary because Znshoot increased significantly with a decrease in pH from 7.5 to 5.5 and rarely changed at pH < 5.5. Sedum plumbizincicola grown in loamy or clay loam soils had larger Znshoot than in sandy or clay soils. The ZnCaCl2 was superior to other methods in estimating Zn bioavailability across all the data. At pH < 5.5, ZnCaCl2 showed much stronger correlation with Znshoot than Zntotal, Znsoln or ZnDGT. Piecewise equations (single linear regression equations at different intervals of soil properties) versus Zntotal and ZnCaCl2 at different pH ranges considerably increased the accuracy of prediction of Znshoot compared with the global equations derived from all data. Estimation of the potential of S. plumbizincicola for Zn phytoextraction in the field indicated that it is feasible to decontaminate acid‐polluted soils with Zntotal ≤ 500 mg kg−1 with S. plumbizincicola. Highlights: Zn bioavailability to hyperaccumulators needs to be estimated over a wide range of soil types.Piecewise equations considerably improved the prediction of shoot Zn concentration.CaCl2 extraction was more suitable than DGT for the estimation of Zn bioavailability.Decontamination with S. plumbizincicola is feasible for acid soils with Zntotal ≤ 500 mg kg−1. [ABSTRACT FROM AUTHOR]

Two pot experiments were conducted to investigate the time course effects of the (S, S)-N, N'-ethylenediamine disuccinic acid (EDDS) addition to contaminated soil on the uptake of Cu and Zn by the Cu accumulator Elsholtzia splendens and on plant Cu and Zn concentrations at different growth stages. EDDS increased the amounts of Cu and Zn soluble in the soil, taken up by plants, concentrated in the xylem sap, and translocated from roots to stems and leaves. The increase in soil-soluble metals, especially Cu, resulted in a corresponding increase in metal concentrations in the xylem sap and leaves. The addition of EDDS to the soil increased plant Cu and Zn concentrations, especially in the leaves, and changed the proportions of Cu and Zn taken up by different plant parts. The proportions of Cu and Zn taken up by the roots were higher than by the leaves of control plants, but EDDS-treated plants showed the opposite trend. EDDS exerted greater effects at the end of the vegetative growth stage than at the start of the flowering or reproductive stages. [ABSTRACT FROM AUTHOR]

Investigates short-term changes in soil hydrogen-ion concentration and trace metal concentrations in oligotrophic forest peat. Tree growth responses to applications of alkaline biosolids; Surface soil metal enrichment; Accumulation of trace metals in the litter layer.

The control of magnetic order and phase-transition dynamics by various means is a key towards low-power spintronics. Here, we report a control on magnetic order and phase-transition dynamics by tuning film thickness in epitaxial FeRh films. Reduction of film thicknesses from 200 nm to 5 nm results in an anti-ferromagnetic to ferromagnetic phase change, accompanied by a 0.55% lattice expansion for c -axis. The phase-transition dynamics is highly dependent on the film thickness, and involves the release and recovery of lattice strain that results in a lower transition temperature and larger thermal hysteresis in thinner films. The findings help to understand the origin of thermal hysteresis and phase-transition dynamics in ultra-thin FeRh films. Possible approaches to narrow down thermal hysteresis are proposed. • A control on the magnetic order and phase-transition dynamics by tuning FeRh film thickness was reported. • The decrease of film thicknesses results in an AFM to FM phase change, accompanied by a 0.55% lattice expansion. • Phase transition dynamics are highly dependent on the film thickness. • Phase transition involves in the release and recovery of strain, leading to lower transition temperature in thinner films. • Possible approaches to narrow down the thermal hysteresis are proposed. [ABSTRACT FROM AUTHOR]

Abstract: ZnO homojunction light emitting device (LED) with n-ZnO:Ga/p-ZnO:N structure was fabricated on sapphire substrate by metal organic chemical vapor deposition. The reproducible p-type ZnO:N layer with hole concentration of 1.29×1017 cm−3 was formed with NH3 as N doping source followed by thermal annealing in N2O plasma protective ambient. The device exhibited desirable rectifying behavior. Distinct electroluminescence emission centered at 3.2eV and 2.4eV were detected from this device under forward bias at room temperature. The intensive ultraviolet emission was comparable to the visible emission in the electroluminescence spectrum, which represent remarkable progress in the performance of ZnO homojunction LED. [Copyright &y& Elsevier]