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The article discusses urban flooding in China. It mentions reasons for the flooding which include loss of natural water bodies, urban land use and imperviousness and fragmentation of natural water systems. It offers suggestions to overcome the problem including protection of natural water bodies, strengthening of efforts made by Chinese government to improve urban ecological environment; and optimization of urban drainage network.

The sorption of dissolved inorganic phosphorus by modified gravel sand (iron-doped and calcined gravel sand) was studied through kinetic, equilibrium, and thermodynamic experiments. The maximum phosphorus sorption capacity of iron-doped and calcined gravel sand was 1.01 and 2.93 mg g−1, respectively. When the solution pH gradually approached a highly alkaline condition, the phosphorus removal efficiency of iron-doped gravel sand decreased sharply and that of calcined gravel sand increased. With an increase in initial phosphorus concentration, the sorption capacity of calcined gravel sand increased significantly (0.8–3.1 mg g−1), and that of iron-doped gravel sand was relatively constant (1.2 mg g−1). Data from the isotherm experiments were well described by Langmuir isotherm model. Kinetic studies illustrated that the rate of sorption followed both the pseudo-first-order and pseudo-second-order models, and that the pseudo-second-order model could better describe the sorption kinetics. The calculated thermodynamic parameters suggested that the sorption was a feasible or spontaneous (ΔG < 0), entropy-driven (ΔS > 0), and endothermic (ΔH > 0) reaction. [ABSTRACT FROM PUBLISHER]

Abstract: We present a frequency multiplication in Metglas/Pb(Zr,Ti)O3 (PZT) magnetoelectric (ME) composites which can be tuned by geomagnetic field. Such effect was observed under small dc magnetic biases, and can be operated over a broad frequency range. Moreover, the geomagnetic field can serve as the “ON–OFF” switch for control of the frequency multiplication in ME composites. Thus, a guidance device could be developed to lock onto the direction with largest component of Earth’s field. [Copyright &y& Elsevier]

This paper investigates magnetoelectric (ME) sensors for vehicle detection. We propose a novel triple-axis ME magnetic sensor system consisting of tri-layers of Metglas/ Pb(Zr, Ti)O3/Metglas laminates together with its fabrication and installation methods. This non-intrusive ME sensor system with a larger sensing range is viable for detection and recognition of vehicle induced magnetic signatures in an outdoor (open) environment. We also show a finite element simulation method capable predicting the magnetic anomaly projection in the geomagnetic field. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present a quasi-static charge amplifier method to detect the extremely low frequency response of Metglas/Pb(Mg1/3Nb2/3)O3–PbTiO3 magnetoelectric (ME) laminated composites. Using this technique, ME effect can be detected at f<10−2 Hz, and ME charge coefficients show good stability over wide frequency range from 10mHz to 1kHz. Thus, it allows us to develop a quasi-static magnetic sensor based on ME composites which can work at frequencies as low as 10mHz, with equivalent magnetic noise floors of about 3nT/√Hz. [Copyright &y& Elsevier]

Key Message: By integrating QTL mapping, transcriptomics and metabolomics, 138 hub genes were identified in rapeseed root response to aluminum stress and mainly involved in metabolism of lipids, carbohydrates and secondary metabolites. Aluminum (Al) toxicity has become one of the important abiotic stress factors in areas with acid soil, which hinders the absorption of water and nutrients by roots, and consequently retards the growth of crops. A deeper understanding of the stress-response mechanism of Brassica napus may allow us to identify the tolerance gene(s) and use this information in breeding-resistant crop varieties. In this study, a population of 138 recombinant inbred lines (RILs) was subjected to aluminum stress, and QTL (quantitative trait locus) mapping was used to preliminarily locate quantitative trait loci related to aluminum stress. Root tissues from seedlings of an aluminum-resistant (R) line and an aluminum-sensitive (S) line from the RIL population were harvested for transcriptome sequencing and metabolome determination. By combining the data on quantitative trait genes (QTGs), differentially expressed genes (DEGs), and differentially accumulated metabolites (DAMs), key candidate genes related to aluminum tolerance in rapeseed were determined. The results showed that there were 3186 QTGs in the RIL population, 14,232 DEGs and 457 DAMs in the comparison between R and S lines. Lastly, 138 hub genes were selected to have a strong positive or negative correlation with 30 important metabolites (|R|≥ 0.95). These genes were mainly involved in the metabolism of lipids, carbohydrates and secondary metabolites in response to Al toxicity stress. In summary, this study provides an effective method for screening key genes by combining QTLs, transcriptome sequencing and metabolomic analysis, but also lists key genes for exploring the molecular mechanism of Al tolerance in rapeseed seedling roots. [ABSTRACT FROM AUTHOR]

A nonlinear magnetoelectric (ME) response has been investigated in a Metglas/piezofiber laminate by applying a bipolar AC magnetic field (Hac) without a DC magnetic bias. The ME voltage (VME) was measured for various amplitudes of Hac of up to 9 Oe over the frequency (f) range 0.1 < f < 40 kHz. Compared to the linear ME behavior, an anomalous response to f and Hac was observed, which is believed to be associated with the Eddy-current loss in the Metglas layers. A frequency multiplication effect was also observed for VME, which was understood by Fourier analysis of the nonlinearity in the magnetostriction. [ABSTRACT FROM AUTHOR]

A magnetoelectric (ME) bending-mode structure based on Metglas/Pb(Zr,Ti)O3 fiber laminates has been studied. This bending mode had a fundamental resonance (FBR) of about 210 Hz, which was much lower than that of the longitudinal mode. Near the FBR, the ME voltage coefficient was about 400 V/cm?Oe. Magnetic sensors based on this bending mode had an equivalent magnetic noise floor of ⩽0.3 pT/√Hz at f = 210 Hz. [ABSTRACT FROM PUBLISHER]

A differential structure which has the ability to reject external vibrational noise for Metglas/Pb(Zr,Ti)O3 (PZT) fiber-based magnetoelectric (ME) heterostructures has been studied. This type of ME structure functions better than conventional sensors as a magnetic sensor when used in an environment in which vibrational isolation is impractical. Sensors fabricated with this differential mode structure can attenuate external vibrational noise by about 10 to 20 dB at different frequencies, while simultaneously having a doubled ME voltage coefficient. Interestingly, in addition to offering a means of mitigating vibrational noise, this ME structure offers the potential to be a hybrid sensor, separating magnetic and acoustical signals. [ABSTRACT FROM PUBLISHER]

Abstract: The magnetic equivalent noise for a 4×4 Metglas/Pb(Zr,Ti)O3 magnetoelectric (ME) sensor array unit has been optimized. Such optimization holds good for practical sensor application in open (unshielded) environments. The self-noise estimation for the array unit was about 15–16.8pT/√Hz at f=1Hz, as estimated by the coherence between each unit and their beam. To verify the efficiency of this optimization technique, self-noise tests were also performed in a magnetic shielding chamber and shown to be close to that of units in an open environment. After employing a noise optimization method, the 4×4 array can achieve a 27dB common mode noise rejection and an equivalent magnetic noise floor of 8.2pT/√Hz at f=1Hz. [Copyright &y& Elsevier]

Abstract: The dielectric and piezoelectric properties of 〈001〉-oriented Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT) fibers and fiber-Kapton core composites were improved by controlling their poling process. An improved poling procedure was identified for the Metglas/PMN–PT sensors, by which sensors exhibited a 1.4× enhancement in the ME coefficient, a 1.6× times reduction in the equivalent magnetic noise floor and a 1.6× times increase in magnetic field sensitivity. [Copyright &y& Elsevier]