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Intensive vegetable production has been characterized by high nitrogen (N) fertilizer input in southwest China. Optimizing the N fertilizer rate is the basis for the optimal management of regional N fertilizer. A two-year field experiment with five N fertilizer rates was conducted during 2019–2021 in southwest China, and the aim of this study was to identify the effects of different N application rates on yield, dry matter biomass (DMB), N uptake, N use efficiency (NUE) and soil mineral N (Nmin) residues for Chinese cabbage (Brassica chinensis L.) and further determine the critical plant N concentration and root-zone soil Nmin residues required to reach the maximum DMB of Chinese cabbage. Five N treatments were established: control without N input (CK); optimal N fertilizer rate decreased by 30% (70% OPT, 175 kg N ha−1), optimized N fertilizer rate (OPT, 250 kg N ha−1), optimal N fertilizer rate increased by 30% (130% OPT, 325 kg N ha−1) and farmers' N fertilizer practice (FP, 450 kg N ha−1). The N source in all treatments was conventional urea (N ≥ 46.2%). The results showed that the total yield of Chinese cabbage followed a "linear-plateau" trend with an increasing N fertilizer rate. There was no significant difference in yield between the OPT, 130% OPT and FP treatments. The aboveground plant DMB and N uptake showed a 'slow-fast-slow' pattern with the growth period. There was no significant difference in aboveground plant DMB and N uptake between the OPT, 130% OPT and FP treatments. Moreover, the OPT treatment significantly increased the aboveground plant DMB and N accumulation by 29.6% and 40.5%, respectively, compared with the 70% OPT treatment. The OPT treatment significantly increased the NUE by 23.8%, 31.2% and 43.1% compared with that in the 70% OPT, 130% OPT and FP treatments, respectively. The linear-plateau model provided the best fit for the relationship among aboveground DMB of Chinese cabbage, plant N concentration and root-zone soil Nmin content. The critical root-zone soil Nmin and plant N concentrations were 94.1, 63.4 and 68.3 kg ha−1 and 34.4, 33.5 and 32.9 g kg−1 during the rosette, heading and harvest periods, respectively. In summary, compared to the FP treatment, the optimized N fertilizer rate (250 kg N ha−1) could significantly reduce the N application rate, maintain yield, increase aboveground plant DMB and N uptake, and improve NUE. Moreover, the study has great significance for guiding the green utilization of vegetable N fertilizer in southwest China. [ABSTRACT FROM AUTHOR]

Satellite communication is expected to play a vital role in realizing Internet of Remote Things (IoRT) applications. This article considers an intelligent reflecting surface (IRS)-assisted downlink low Earth orbit (LEO) satellite communication network, where IRS provides additional reflective links to enhance the intended signal power. We aim to maximize the sum-rate of all the terrestrial users by jointly optimizing the satellite's precoding matrix and IRS's phase shifts. However, it is difficult to directly acquire the instantaneous channel state information (CSI) and optimal phase shifts of IRS due to the high mobility of LEO and the passive nature of reflective elements. Moreover, most conventional solution algorithms suffer from high computational complexity and are not applicable to these dynamic scenarios. A robust beamforming design based on graph attention networks (RBF-GAT) is proposed to establish a direct mapping from the received pilots and dynamic network topology to the satellite and IRS's beamforming, which is trained offline using the unsupervised learning approach. The simulation results corroborate that the proposed RBF-GAT approach can achieve more than 95% of the performance provided by the upper bound with low complexity. [ABSTRACT FROM AUTHOR]

Wearable devices have become an important development direction for future consumer electronics, and films with conductivity, stretchability, and transparency are crucial for achieving wearability. In this article, silver nanowires (AgNWs) with a certain aspect ratio and Al2O3-polyethylene terephthalate films with specific size pit structures were prepared. Uniform coating of the AgNW layer and polydimethylsiloxane transfer were successfully realized. The surface resistance of the final obtained film was 14 Ω/sq with a light transmittance of 50.57%. During repeated deformations, the film conductivity was not significantly reduced, and excellent electrical conductivity was maintained. A relatively complicated flexible AgNW circuit was prepared by adding a patterned mask in the scrape-coating step. This is a low-cost method and can be used to form large films. The final product has excellent conductivity and some transparency and can provide new research directions for flexible electronic devices. [ABSTRACT FROM AUTHOR]

Double-band circular polarization conversion based on novel e -shape resonators is proposed and studied both numerically and experimentally. Both the simulated results and experimental results are in good agreement. At two resonant frequencies, i.e., 11.65 GHz and 13.02 GHz, the incident y-direction linearly polarized wave can be transformed into right- and left-handed circularly polarized waves, respectively. The proposed structure can transmit a nearly pure circularly polarized wave, with a polarization extinction ratio of greater than 30 dB. Moreover, the metasurface is compact with simple geometry, which is not only extremely thin in the propagating direction but also very small in the transverse direction. The retrieval results reveal that the effective refractive index of the e -shape structure is nearly negative in the vicinity of resonant frequencies. The surface current distributions are investigated to illustrate the polarization transformation mechanism. We also analyze the influence of several main geometric parameters for regulating the polarization properties. The proposed e -shape structure is promising for use in the design of polarization control devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dislocation networks generate in a way similar to the spider's orb-weaving process. • Boundaries formed by the weaving process act as preferred cracks propagation pathways. • The dislocations-weaving process can increase the ductility of tungsten. Dislocation is the primary carrier for accommodating plastic deformation in metals. It is generally envisaged that metals with low initial dislocation density have high strain-to-failure and good formability, and vice versa. However, contrary to most metals, body-centered-cubic pure tungsten becomes brittle after reducing its dislocation density by recrystallization, while its formability increases after heavy deformation. To elucidate the mechanism of this counterintuitive mechanical behavior, by combining ex-situ indentation tests and dislocation reconstruction techniques, we find that tungsten's deformation and failure processes are accompanied by the formation of a specific dislocation pattern. Dislocation networks are governed by a mechanism similar to the weaving process of the spider's orb web. After heavy deformation, subgrains are generated due to the weaving process. The recurring weaving of dislocations reduces the mean free path for crack propagation, which is considered as the main reason for the increased formability of tungsten after deformation. [ABSTRACT FROM AUTHOR]

By investigating the change of microstructure features in the presence and absence of hydrogen, we studied the influence of internal hydrogen on the plastic deformation ahead of a crack tip in tungsten foil. After micromechanical loading, ahead of the crack tip in the hydrogen-charged tungsten, we found an intermittent plastic zone composed of dislocation tangles and a dislocation network with an L -square shape. The L -square dislocation structure tended to move along the crack propagation direction. These observations are attributed to the hydrogen effect on the energy release rate and the stress intensity factor. The propagation of crack is considered a result of the competition between H-modified dislocation motion and H-induced decohesion. [Display omitted] • Hydrogen-assisted crack propagation generates intermittent plastic zones and L -square dislocation structures in tungsten foil. • The L -square dislocation configuration moves with the crack front in the presence of hydrogen. • Competition between hydrogen-modified dislocation motion and hydrogen-induced decohesion controls the hydrogen-assisted cracking process in tungsten foil. [ABSTRACT FROM AUTHOR]

In this paper, we theoretically and experimentally report an achiral dual-band metasurface with linear birefringence. The unit cell of the achiral metasurface consists of non-twisted Q-shape metallic ring resonators with a stub breaking the rotational symmetry. Moreover, due to the presence of the stub, we find the proposed metasurface emits dual-band circularly polarized wave with low transmission loss and high polarization extinction for a normal incident y-direction linearly polarized wave. We also systematically investigate the dependence of the electromagnetic response of the proposed structure on the geometric parameters. It is hoped that the proposed simple, easily fabricated model of achiral metasurface can be used in further polarization control applications [ABSTRACT FROM AUTHOR]

Abstract: Epoxy resins reinforced, respectively, by basalt fibres and glass fibres were treated with a seawater solution for different periods of time. Both the mass gain ratio and the strength maintenance ratio of the composites were examined after the treatment. The fracture surfaces were characterized using scanning electron microscopy. The tensile and bending strengths of the seawater treated samples showed a decreasing trend with treating time. In general, the anti-seawater corrosion property of the basalt fibre reinforced composites was almost the same as that of the glass fibre reinforced ones. Based on the experimental results, possible corrosion mechanisms were explored, indicating that an effective lowering of the Fe2+ content in the basalt fibre could lead to a higher stability for the basalt fibre reinforced composites in a seawater environment. [ABSTRACT FROM AUTHOR]

Abstract: Basalt and glass fibers were treated with sodium hydroxide and hydrochloric acid solutions respectively for different periods of time. Both the mass loss ratio and the strength maintenance ratio of the fibers were examined after the treatment. The morphologies of the fiber surfaces were characterized using scanning electron microscopy and their compositions were analyzed using energy dispersive X-ray spectroscopy. For the basalt fibers, the acid resistance was much better than the alkali resistance. Nevertheless, for the glass fibers, the acid resistance was nearly the same as the alkali resistance. Based on the experimental results, possible corrosion mechanisms are addressed. [Copyright &y& Elsevier]

Abstract: The treated basalt and glass fibers with sodium hydroxide and hydrochloric acid solutions for different times were analyzed, respectively. This paper summarized the mass loss ratio and the strength maintenance ratios of the fibers after treatment. The fibers’ surface corrosion morphologies were characterized using scanning electron microscopy and their compositions were detected using energy dispersive X-ray spectroscopy. The acid resistance was much better than the alkali resistance for the basalt fibers. Nevertheless, for the glass fibers the situation is different: the acid resistance was almost the same as the alkali resistance. Among the two types of aqueous environments evaluated, the alkali solution is the most aggressive to the fibers’ surface. The possible corrosion mechanisms are revealed. [Copyright &y& Elsevier]

Abstract: An intermittent electrochemical treatment method was developed in this work which was used to modify the surface of carbon fibers in three-dimensional fabrics. The effects of this treatment on the surface chemical components of the fibers in both interior and surface regions of the fabrics were analyzed by X-ray photoelectron spectroscopy. The wettability of the fabrics was evaluated by liquid-drop method. A microdebonding method was employed to determine the uniformity of interfacial shear strength between the fibers and the matrix in different regions of the carbon fabric/phenolic composites. The compressive strength was also tested to evaluate the effects of treatment. The results indicated that the intermittent electrochemical treatment significantly improved the interfacial adhesion by etching and generating oxygenic and nitrogenous functional groups. The processibility of the fabrics was also improved due to improved impregnation of phenolic resin with the fabrics. The compressive strength was significantly increased due to optimized intermittent electrochemical treatment. Moreover, comparing with the traditional continuous electrochemical treatment which the treatment degrees of the fibers in different region of the fabrics were different, the intermittent treatment was a useful method to obtain the relatively uniform properties throughout the fabrics. [Copyright &y& Elsevier]

In this paper, a reconfigurable sensing platform based on an asymmetrical metal-insulator-metal stacked structure integrating an indium tin oxide (ITO) ultrathin film is proposed and investigated numerically. The epsilon-near-zero (ENZ) mode and antisymmetric mode can be resonantly excited, generating near-perfect absorption of over 99.7% at 1144 and 1404 nm, respectively. The absorptivity for the ENZ mode can be modulated from 90.2% to 98.0% by varying the ENZ wavelength of ITO by applying different voltages. To obtain a highly sensitive biosensor, we show that the proposed structure has a full-width at half-maximum (FWHM) of 8.65 nm and a figure-of-merit (FOM) of 24.7 with a sensitivity of 213.3 nm/RI (refractive index) for the glucose solution. Our proposed device has potential for developing tunable biosensors for real-time health monitoring. [ABSTRACT FROM AUTHOR]

We propose a novel and simple method to achieve perfect light absorption over a broadband by coupling a gap plasmon mode to an epsilon-near-zero (ENZ) mode, which is a new path for tailoring light-matter interactions. Near-perfect light absorption (over 99%) in the wavelength range of 1400 nm–1655 nm can be achieved utilizing a gold-disk periodically patterned metal-dielectric-metal (MDM) device by integrating an ultrathin ITO (indium tin oxide) film. The ENZ mode can be excited effectively by coupling the gap plasmon resonance to conducting ITO (indium tin oxide) nanolayer (ENZ wavelength of the ITO nanofilm close to 1403 nm) under normal incidence. Compared with the device without ITO nanolayer, the device integrating ITO ultrathin film shows wideband perfect light absorption. Besides, the thickness of SiO 2 spacer layer is critical for the coupling strength of metamaterial resonator and ENZ mode. To achieve broadband absorption, the coupling strength of the ENZ mode and gap plasmon mode should be between the strong coupling and weak coupling regimes. The method is also effective for the design of multiband optoelectronic devices with simple structure and low cost. • A novel design strategy of broadband perfect absorbers by coupling a gap plasmon mode to an epsilon-near-zero mode (ENZ) is presented and numerically investigated. • Near-perfect light absorption (over 99%) in the wavelength range of 1400 nm–1655 nm can be achieved due to the excitation of ENZ mode. • The coupling strength of the ENZ mode and gap plasmon mode should be between the strong coupling and weak coupling regimes to achieve broadband absorption for light. • The method is also useful in the design of multiband optoelectronic devices with simple structure and low cost. [ABSTRACT FROM AUTHOR]

We present theoretical studies for the third-order elastic constants of Mg, Be, Ti, Zn, Zr, and Cd with a hexagonal-close-packed (HCP) structure. The method of homogeneous deformation combined with first-principles total-energy calculations is employed. The deformation gradient F i j is applied to the crystal lattice vectors r i , and the elastic strain energy can be obtained from the first-principles calculation. The second- and third-order elastic constants are extracted by a polynomial fit to the calculated energy-strain results. In order to assure the accuracy of our method, we calculated the complete set of the equilibrium lattice parameters and second-order elastic constants for Mg, Be, Ti, Zn, Zr, and Cd, and our results provide better agreement with the previous calculated and experimental values. Besides, we have calculated the pressure derivatives of SOECs related to third-order elastic constants, and high-pressure effects on elastic anisotropy, ductile-to-brittle criterion, and Vickers hardness are also investigated. The results show that the hardness model H v = 1.877 k 2 G 0.585 is more appropriate than H v = 2 k 2 G 0.585 − 3 for HCP metals under high pressure. [ABSTRACT FROM AUTHOR]

Phase manipulation plays a fundamental role in electromagnetic (EM) and optics research, i.e., the wavefront shaping depends heavily on phase modulation. However, the previous phase manipulation methods are limited to phase‐angle dimensionality, and the magnitude and phase are generally deemed as two distinct characters that should be controlled separately. Herein, a phase manipulation method in which phase is modulated by magnitude is proposed that follows an EM expression of Euler's formula. A rotation phase of linearly‐polarized waves is presented. Using this method, several unique applications in this research are demonstrated. First, a Hall effect of non‐angular‐momentum waves is obtained; second, an interdigital topology model with a unique topological‐charge control strategy is presented; and finally, the method is applied to holographic imaging, of which information of the hologram is recorded as a distribution of magnitude. Furthermore, as this method is applicable to all forms of harmonic waves, it can be potentially applied to other areas of wave phenomena such as acoustics and mechanics. [ABSTRACT FROM AUTHOR]

The triboelectric nanogenerator (TENG) and its application as a sensor is a popular research subject. There is demand for self-powered, flexible sensors with high sensitivity and high power-output for the next generation of consumer electronics. In this study, a 300 mm × 300 mm carbon nanotube (CNT)-doped porous PDMS film was successfully fabricated wherein the CNT influenced the micropore structure. A self-powered TENG tactile sensor was established according to triboelectric theory. The CNT-doped porous TENG showed a voltage output seven times higher than undoped porous TENG and 16 times higher than TENG with pure PDMS, respectively. The TENG successfully acquired human motion signals, breath signals, and heartbeat signals during a sleep monitoring experiment. The results presented here may provide an effective approach for fabricating large-scale and low-cost flexible TENG sensors. [ABSTRACT FROM AUTHOR]

Exploring flexible dielectrics with high dielectric constant and low loss is pertinent for many applications in electronic devices. In the present work, a non-ferroelectric polymer, polyvinyl alcohol (PVA), was used to fabricate homogeneous dielectric composite films with a relatively high dielectric constant and a low dielectric loss by using 2D nano sheets (Ti 3 C 2 T x MXene) as the filler. To limit dielectric loss, SiO 2 was coated onto the surface of MXene to provide interfacial barrier effect and suppress dielectric loss. MXene@SiO 2 /PVA composite films showed lower dielectric losses at low frequencies (from 20 Hz to ~ 10 kHz) compared with MXene/PVA composite films. MXene@SiO 2 /PVA composite films with 2.5 wt% MXene loading and 5 wt% (with respect to MXene content) SiO 2 coating had a dielectric constant of 27.2 (a 292.5% rise compared to neat PVA film) and a dielectric loss of only 0.057 (a 259.6% reduction compared to MXene/PVA composite film) at 100 Hz and room temperature (RT). In addition, this SiO 2 -coated composite film had stable dielectric properties (dielectric constant and loss change from 27.2 to 29.3 and 0.057 to 0.104, respectively) in the temperature range of RT to 60 °C. This work provides a promising way to fabricate PVA-based dielectric composites with excellent dielectric properties for practical applications in electronics. [ABSTRACT FROM AUTHOR]

This article has been retracted: please see Elsevier Policy on Article Withdrawal ( http://www.elsevier.com/locate/withdrawalpolicy ). This article has been retracted at the request of the Editors. The article duplicates significant parts of a paper that had already appeared in Mater. Des., 2010, 31 (9) 4244–4250, http://dx.doi.org/10.1016/j.matdes.2010.04.009 . One of the conditions of submission of a paper for publication is that authors declare explicitly that the paper is not under consideration for publication elsewhere. Re-use of any data should be appropriately cited. As such this article represents a severe abuse of the scientific publishing system. The scientific community takes a very strong view on this matter and apologies are offered to readers of the journal that this was not detected during the submission process. [ABSTRACT FROM AUTHOR]

Porous materials with corrugated surfaces are widely used in the field of noise control, as they can effectively convert sound energy into heat resulting in sound absorption. It is important to predict the absorption coefficients of sound-absorbing devices for the design of appropriate shape and size. In this study, a semi-analytic method of layered rigorous coupled-wave analysis (LRCWA) is proposed to predict the absorption of nonplanar periodic materials. Starting from the division of corrugated surfaces into multiple layers, we process the sound behavior in each layer as in a rectangular periodic modulation structure. By connecting the interlayer boundary continuity conditions, the acoustic coupling equation of the whole structure can be established. The effectiveness and practicability of the LRCWA method is validated based on the comparisons with the experimental data and the simulation of finite element method. Besides the absorption coefficient that is mainly discussed in this work, the proposed method is universal in analyzing the physical properties of nonplanar periodic structures, which can greatly accelerate the delicate design and optimization of such structures. [ABSTRACT FROM AUTHOR]

Optical and microwave communication classically focus more on the magnitude manipulation of electromagnetic carriers. Recently, a multiplexing method utilizing orbital angular momentum (OAM) is developed, which has been an important study of communication art. Based on OAM multiplexing, a communication method that introduces Berry‐phase carriers is presented in this research, which can naturally eliminate the channel disturbance. To verify the proposed method, two information systems are presented, including a multiplexing communication system in a large‐scale scenario and a double‐helical information system in a microscale scenario. All the results are verified by the corresponding experiments. This method achieves some advanced performances, for instance, directional communication and self‐anti‐interference, which shows potential applications in areas such as information, materials, and bionics. [ABSTRACT FROM AUTHOR]

We report on the observation of the electromagnetic focusing effect of zero orbital angular momentum (OAM) after introducing the multi-grade OAM concept. It performs the same feature in the central area around the focal point, while the typical Airy disk is transformed into a vortical cloud pattern beside the central area. Quantized focusing phenomena are exhibited based on the periodicity of the OAM. These results were verified by simulation and experiments. Our method achieves an optical focusing theory through OAM manipulation, which can be applied in imaging, photoetching, and communication. Furthermore, it also provides an opportunity for energy harvesting from natural OAM materials. [ABSTRACT FROM AUTHOR]

Abstract: Coatings, which were made from pure epoxy and SiO2 nanoparticle modified epoxy composite, respectively, were applied onto the basalt fiber rovings. The SiO2 nanoparticles were synthesized using a sol–gel method and modified using coupling agent. Fourier transform infrared spectroscopy (FT-IR) and Differential Scanning Calorimetry (DSC) analyses indicated the formation of modified SiO2 nanoparticles. The SiO2 nanoparticle–epoxy composite coating gave rise to a significant increase in the tensile strength of the basalt fibers as compared with the pure epoxy coating, and also the coating endowed the basalt fiber with a promising interfacial property in the basalt fiber reinforced resin matrix composite. The coating modification was an effective way in improving the mechanical properties of basalt fibers and the properties of basalt fiber/epoxy resin composites. [Copyright &y& Elsevier]

Abstract: A novel isomeric polyimide/SiO2 hybrid material was successfully prepared through sol–gel technique, and its structure, thermal properties and nano-indenter properties were investigated. First, 3-[(4-phenylethynyl)phthalimide]propyl triethoxysilane (PEIPTES) was successfully synthesized, its structure was characterized by elemental analysis, FT-IR and 13C NMR. The researches on solubility and thermal properties of PEIPTES show that it can be used for modifying nano-SiO2 precursor. Nano-SiO2 precursor was synthesized by tetraethoxysilane (TEOS) through sol–gel technique. Then the PEIPTES solution and the nano-SiO2 precursor were mixed for 6h to let the PEIPTES molecules react with the nano-SiO2 precursor, and modified nano-SiO2 precursor was obtained. The modified reaction was confirmed by the analyses of FT-IR. At last, isomeric polyimide/SiO2 hybrid material was produced by using isomeric polyimide resin solution and the modified nano-SiO2 precursor after heat treatment process. The structure analysis by SEM indicated that SiO2 particles dispersed in isomeric polyimide matrix homogeneously with nanoscale. Thermogravimetric analyzer, dynamic mechanical thermal analyzer and nano-indenter XP was employed to detect the properties of the materials, the results demonstrated that isomeric polyimide/SiO2 hybrid material has much better thermal properties and nano-indenter properties than those of isomeric polyimide. It is confirmed that PEIPTES acts as a bridge between the SiO2 particles and the isomeric polyimide matrix in the hybrid material, because the ethoxyl of PEIPTES could participate in the hydrolyzation and condensation to form chemical bond with SiO2 particles and its phenylethynyl group could take part in the cross-curing reaction of isomeric polyimide. [Copyright &y& Elsevier]

Piezoelectric composites will cause different degrees of deformation when ambient temperature changes during transportation, storage and use, affecting the performance and reliability seriously. The deformation measurement of cylindrical piezoelectric composites based on fiber Bragg grating (FBG) measurement is presented in this paper. The deformation and electromechanical properties of cylindrical piezoelectric composites over a wide range of temperature, from 233 K to 373 K, are investigated in detail. The deformation of piezoelectric composites in different directions is calculated. Adding deformation information, the frequency constant and dielectric constant data are modified. The results show that, at 233 K, the relative change of curvature of the cylindrical composite material in the arc direction is 0.024% and the relative change of deformation in the width and thickness direction are 0.018% and 0.026%, respectively. When the environment's temperature is increased to 100℃, the relative change of curvature in the arc direction is 0.019% and the relative changes of deformation in the width and thickness direction are 0.019% and 0.008%, respectively. After adding the deformation information, the most evident changes of frequency constant and dielectric constant are between 303 K and 333 K, the rate of change (slope) of frequency constant and the dielectric constant are −1.82983 kHz·mm/K(decreasing) and 3.85591 kHz·mm/K(increasing), respectively. [ABSTRACT FROM AUTHOR]

The geopolymer containing the special porous structure unit sod (t-toc) cage, which can be made from fly ash, is a possible economic solution to reduce toxicity of hazardous heavy metals by its excellent immobilization potential. Herein, the zeolite sodalite which is composed of sod (t-toc) cage was selected to model the geopolymer to uncover the immobilization mechanisms for the hazardous heavy metal ions Cr3+, Pb2+, Zn2+, Cu2+, Hg+, Cd2+ and Ni2+ in this work. Based on experimental crystalline structures, exchange energy was introduced for the first time to quantitatively evaluate the immobilization long-term stability theoretically. The immobilization of hazardous heavy metal ions were discovered to be determined by the solvation from the crystalline H 2 O and bonding from the sod (t-toc) cage. Based on the analysis of exchange energies, it was found that the immobilization for these heavy metals was correlated with the solvation radius: the larger the solvation radius was, the more favorable the immobilization was. Further detailed solvation effect analysis indicates that the immobilization of heavy metal ions is very sensitive to solvation effect based on the crystalline H 2 O molecules. Due to the synergistic effect between the solvation effect and the adsorption of the sod (t-toc) cage, the immobilization of Zn2+ is always favorable inside sodalite whereas Cr3+, Cd2+, Cu2+, Ni2+ and Pb2+ could be unfavorable in the case of insufficient solvation. This study provides a fast, convenient and objective way to evaluate the immobilization of heavy metals. Image 1 • Exchange energy is a good indicator to evaluate the immobilization of heavy metals. • The larger the metal's solvation radius is, the more favorable the immobilization is. • The immobilization order in sodalite is: Cr3+ > Zn2+ > Cd2+ > Cu2+ > Ni2+ > Pb2+. • The immobilization of heavy metal ions is very sensitive to the solvation effect. [ABSTRACT FROM AUTHOR]

Herein, we propose an approach for sensitivity improvement of dual-axis strain sensing using the property of a metasurface (MS) that the phase response shifts sharply with the MS deformation. A feasible approach for phase measurement is first demonstrated by calculating multi-polarized reception when the incident electromagnetic (EM) wave has anisotropic phase values. A flexible MS consisting of periodically arranged lantern-shaped elements is designed and fabricated for dual-axis strain sensing and evaluation based on the proposed method. The simulation and measurement results demonstrated a high sensitivity of the proposed MS for strain sensing in the microwave band. The method can be used potentially in both pressure and tensile sensing. Moreover, the operational frequency can be extended to the THz range and even to the optical band. [ABSTRACT FROM AUTHOR]

• Zonation of inner products of GGBFS were controlled by adding PAS. • Strength promotion and refined pore structure of GGBFS blended paste were obtained by adding PAS. • Dissolution of GGBFS were promoted by adding PAS. In this study, polyaluminum sulfate (PAS) is added into slag blended cement pastes to controll the inner zonation of the hydrotalcite-like phase. Nano-structure of inner hydration product region of slag after adding PAS is studied using TEM. Mean reaction degree of slag in the blended pastes was calculated using the deconvolution of 29Si NMR results. Adding PAS causes a hydrotalcite-like phase zonation with a loosen nanostructure in the inner region of slag, facilitating ion diffusion and the continuous growth of hydration products. Thus, promoted hydration degree of slag, enhanced compressive strength and refined pore structure are obtained by adding PAS in the blended pastes. Adding PAS by 2% promotes dissolution of slag particles and increases the mean reaction degree of slag in the blended pastes at 14, 28 and 56 d. Adding PAS by 2% decreases the porosity of blended pastes to 12.63%, thus increasing the compressive strength up to 20% at 28d. [ABSTRACT FROM AUTHOR]

Background: Electroconvulsive therapy (ECT) is an important treatment option for patients with major depressive disorder (MDD). However, the mechanisms of ECT in MDD are still unclear.Methods: Twenty-four patients with severe MDD and 14 healthy controls were enrolled in this study. Eight ECT sessions were conducted for MDD patients using brief-pulse square-wave signal at bitemporal locations. To investigate the regional cerebral blood flow in MDD patients before and after ECT treatments by resting-state functional magnetic resonance imaging (rs-fMRI), the patients were scanned twice (before the first ECT and after the eighth ECT) for data acquisition. Afterward, we adopted fractional amplitude of low-frequency fluctuations (fALFF) to assess the alterations of regional brain activity.Results: Compared with healthy controls, the fALFF in the cerebellum lobe, parahippocampal gyrus, fusiform gyrus, anterior cingulate gyrus, and thalamus in MDD patients before ECT (pre-ECT) was significantly increased. In another comparison, the fALFF in the cerebellum anterior lobe, fusiform gyrus, insula, parahippocampal gyrus, middle frontal gyrus, and inferior frontal gyrus in pre-ECT patients was significantly greater than the post-ECT fALFF.Limitations: Only two rs-fMRI scans were conducted at predefined times: before the first and after the eighth ECT treatment. More scans during the ECT sessions would yield more information. In addition, the sample size in this study was limited. The number of control subjects was relatively small. A larger number of subjects would produce more robust findings.Conclusions: The fALFF of both healthy controls and post-ECT patients in cerebellum anterior lobe, fusiform gyrus, and parahippocampal gyrus is significantly lower than the fALFF of pre-ECT patients. This finding demonstrates that ECT treatment is effective on these brain areas in MDD patients. [ABSTRACT FROM AUTHOR]

Caused by strong winds or nonuniform icing, conductor galloping is one of the major hazards that should be monitored in a timely fashion. In this paper, we proposed a new full-scale reconstruction method for transmission line curves based on the attitude sensors that uses only the tangential information and arc-length constraint. Meanwhile, a comparatively low-complexity algorithm is presented: (1) quaternion rotation to generate the tangent vectors; (2) a modified B-spline global interpolation to evaluate the curvature information; and (3) a linear mapping method to correct reconstruction curves. Moreover, sensors placement method is put forward according to the galloping features. Finally, both simulation and experimental results demonstrate that the proposed method can accurately reconstruct the galloping curves in a relatively short time, which fulfills the requirement of the real-time galloping monitoring system. [ABSTRACT FROM AUTHOR]

The structural and electrical parameters of leakage inductance transformers can significantly affect the efficiency, noise, and vibration of microwave ovens. The paper proposed a new iron core structure with finite element modeling and simulations of a leakage inductance transformer by both the electromagnetic field and system design simulation software. Different silicon steel sheet models were used for the upper and lower parts of the proposed iron core to reduce the loss and heat of the leakage inductance transformer. The iron core scheme was changed from the traditional E-I type to the E-E type. The feasibility of the new iron core scheme was tested by numerical results which showed that the maximum temperature rise of the leakage inductance transformer decreased significantly. [ABSTRACT FROM AUTHOR]

For the power electronics devices with the insulated gate bipolar transistors, the thermal management is very important and necessary for the devices reliability. In this paper, power losses of the inverter were evaluated based on its electro-thermal model and control logic. Accordingly, its thermal management system using forced air cooling is designed and simulated. The transient temperature filed simulation results showed that the thermal management system is feasible and can guarantee the working temperature of the inverter. Experimental results were also obtained to verify the simulation results in this paper. [ABSTRACT FROM AUTHOR]

Accurate focusing of high-resolution highly squinted azimuth variant bistatic synthetic aperture radar is a more challenge issue than its translational azimuth invariant bistatic counterpart due to the following two reasons: 1) higher order terms spatial variant feature in azimuth caused by removing relatively large range migration and 2) the azimuth-dependent range offset (RO) induced by inherent azimuth variant bistatic geometric configuration. In this paper, to solve those two issues, a geometry information-aided extended azimuth nonlinear chirp scaling algorithm to provide a better focus is proposed. First, the range compression containing two procedures, namely a linear range walk correction operation and a bulk secondary range compression, is utilized. Second, based on the geometry property of azimuth variant bistatic geometric configuration, the azimuth-dependent RO is obtained and then compensated to enhance focusing ability in the azimuth dimension. By evaluating the spatial variant characteristic of the frequency modulation (FM) rate and the higher order terms, a new azimuth scaling function is derived by adopting higher order approximation operation. With this new azimuth scaling function, not only the azimuth spatial variances of the higher order terms of FM rate and cubic phase terms are equalized, but also the azimuth-dependent RO is eliminated. Compared with existing azimuth nonlinear chirp scaling method, large azimuth depth of focusing can be realized without changing the overall imaging procedure. The experimental results with simulated data verify the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

A novel dual‐band bandpass filter (BPF) based on a single triple‐mode ring resonator is proposed. The proposed BPF could provide three transmission poles for each passband to improve operating bandwidth. Meanwhile, seven transmission zeros are achieved at the stopband to improve the selectivity. The proposed dual‐band BPF was designed, fabricated and tested. The measured results are in good agreement with the simulated values. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a new treatment method based on molecular self-assembly on carbon fiber surface was proposed for obtaining a controlled interface between carbon fiber and epoxy matrix in composite system. To form the controlled interfacial region, the surfaces of carbon fibers were first metallized by electroless Ag plating, then were reacted with a series of thiols (different chain lengths and terminally functional groups) to form self-assembly monolayers (SAMs), which further reacted with epoxy resin to generate a strong adhesion interface. The morphology, structure and composition of untreated and treated carbon fiber surface were investigated by atomic force microscope (AFM), surface-enhanced Raman scattering spectroscopy (SERS) and X-ray photoelectron spectroscopy (XPS), respectively. SERS study showed that thiols chemisorbed on Ag/carbon fiber in the form of thiolate species via the strong S–Ag coordinative bond. XPS study further confirmed the chemisorption by an S 2p3/2 component observed at 162.2eV. The binding energy was characteristic of silver thiolate. The interfacial shear strength of the carbon fiber/epoxy microcomposites was evaluated by the microbond technique. The results showed that there was a direct effect of the interfacial parameters changes such as chain lengths and surface functional groups on the fiber/matrix adhesion. [Copyright &y& Elsevier]

A chemical industrial park is a socioeconomic and ecological composite system formed by the interaction of multiple stakeholders, such as chemical companies, the government, and the public. The environmental governance of chemical industrial parks requires the participation of multiple parties. However, when considering the environmental problems of chemical industrial parks, researchers mainly investigate such problems based on the parks or the government, and there is a lack of research from the perspective of multiple subjects. In this paper, we take public participation in China's chemical industrial parks as an example and, based on semi-structured interviews and questionnaires, analyse the current situation of public participation in the environmental governance of chemical industrial parks. We find that public participation is characterized by a situation of "helplessness". This helplessness has three causes: (1) a weak foundation for public participation, (2) limited public participation channels and (3) ineffective CIP management committees. We also discuss changes required at the government level, fostering public participation in environmental governance of chemical industrial parks and implications for theory and practice on cleaner production. [ABSTRACT FROM AUTHOR]

The current ceramic/618 epoxy resin piezoelectric composite material is easily deformed due to temperature, which affects the performance of the transducer to send and receive signals. Therefore, finding piezoelectric composite materials with higher temperature stability has become an urgent task. In this paper, the temperature stability of two piezoelectric composite materials of ceramic/ 618 epoxy resin and ceramic/9110 W silicone resin in the range of 25 °C ~ 120 °C was investigated via the fiber Bragg grating method. The results show that, during 25 °C to 120 °C, the ceramic/9110 W silicone resin piezoelectric composite has obvious less deformation and more stable electromechanical properties than the ceramic/ 618 epoxy resin piezoelectric composite; its increase rate of deformation in three directions of length, width and thickness are 8.269 × 10−5 mm/°C, 6.728 × 10−6 mm/°C, and 8.476 × 10−6 mm/°C respectively; its resonant frequency, relative rate of change of frequency constant, quasi-static capacitance, relative dielectric constant and conductance increase with increasing temperature, and the maximum values are 289 kHz, 0.1529%, 1.67 nF, 1083.225 and 11.300 ms, respectively; its electromechanical coupling coefficient changes little with increasing temperature, the maximum and minimum values are 0.63 and 0.60, respectively. The ceramic/9110 W silicone resin piezoelectric composite can better ensure the stability of the transducer performance. [ABSTRACT FROM AUTHOR]

• To our best knowledge, we are the first to use deep learning for fully automatic functional region annotation of liver, demonstrating its ability to meet the challenge of classifying hepatic segments. • The anatomy class-specific information was used to solve the problem of the class crossing between slices. • A 2.5D spatial adaptation input module to overcome the problem of inconsistency in slices spatial information was designed. • We manually annotated 112 CT cases from the Task08_HepaticVessel in the Medical segmentation Decathlon study [25] over 3 months, and validated this pipeline on our data. Automatic functional region annotation of liver should be very useful for preoperative planning of liver resection in the clinical domain. However, many traditional computer-aided annotation methods based on anatomical landmarks or the vascular tree often fail to extract accurate liver segments. Furthermore, these methods are difficult to fully automate and thus remain time-consuming. To address these issues, in this study we aim to develop a fully-automated approach for functional region annotation of liver using deep learning based on 2.5D class-aware deep neural networks with spatial adaptation. 112 CT scans were fed into our 2.5D class-aware deep neural network with spatial adaptation for automatic functional region annotation of liver. The proposed model was built upon the ResU-net architecture, which adaptively selected a stack of adjacent CT slices as input and, generating masks corresponding to the center slice, automatically annotated the liver functional region from abdominal CT images. Furthermore, to minimize the problem of class-level ambiguity between different slices, the anatomy class-specific information was used. The final algorithm performance for automatic functional region annotation of liver showed large overlap with that of manual reference segmentation. The dice similarity coefficient of hepatic segments achieved high scores and an average dice score of 0.882. The entire calculation time was quite fast (~5 s) compared to manual annotation (~2.5 hours). The proposed models described in this paper offer a feasible solution for fully-automated functional region annotation of liver from CT images. The experimental results demonstrated that the proposed method can attain a high average dice score and low computational time. Therefore, this work should allow for improved liver surgical resection planning by our precise segmentation and simple fully-automated method. [ABSTRACT FROM AUTHOR]