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In order to achieve anti-jamming, radar needs to identify the jamming signals to distinguish between the target echo signals and the jamming signals. Interrupted sampling repeater jamming (ISRJ) is a widely used jamming type in radar and electronic countermeasures. In this paper, we propose an efficient channel attention (ECA)-based one-dimensional residual neural network method for the ISRJ signal recognition. The joint features based on axially integral bispectrum and square integral bispectrum are used to extract the target echo signal and ISRJ signal. The ECA-based one-dimensional residual neural network is applied to the ISRJ recognition. The experiment results show that the proposed ECA-based one-dimensional residual neural network has better correct recognition rate under low signal-to-noise ratio and can offer 30.17% reduction in timeliness than the improved convolutional neural network-residual network (CNN-ResNet) method. [ABSTRACT FROM AUTHOR]

Software radio channelizer is employed in the multi-standard wireless communication for extracting individual channels from the wideband input signal. Frequency response masking (FRM) finite impulse response (FIR) filters are used in software radio channelizer for reducing the computational complexity of the maximally decimated filter bank (MDFB) with narrow transition band (NTB). In this paper, we present an approach to design two well-known classes of efficient digital filters, namely the interpolated and full FRM FIR filters. In the proposed MDFB, the FRM is used to obtain flexible transition band and low complexity. The proposed improved FRM-based MDFB with NTB can be directly applied to high sampling rate software radio channelizer. We show the FRM filter examples for single carrier orthogonal frequency division multiplexing (SC-OFDM) modulator and wideband digital receiver (WDR). The simulation results indicate that the improved FRM-based MDFB with NTB is correct. Design examples with complexity comparison are presented to demonstrate the complexity improvement of the proposed FRM-based MDFB with NTB. [ABSTRACT FROM AUTHOR]

Temperature/pH-responsive hydrogels are one of the most studied environmental-responsive hydrogels, with sensitivity and rapid response being the sought-after properties, while sensitivity and reusability are generally poor. This study prepared a hydrogel with a temperature/pH-responsive core-shell structure by static template polymerization, using the temperature-sensitive monomer dimethylaminoethyl methacrylate polymerized with 2-acrylamide-2-methylpropanesulfonic acid as the temperature-sensitive shell and popcorn with acrylic acid as the pH-responsive core-layer hydrogel. The chemical structure, thermal stability, and morphology of the core-shell structure hydrogels were characterized by Infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer-Emmett-Teller surface (BET), Scanning electron microscopy (SEM), Atomic force microscopy (AFM) and Thermogravimetric analysis (TG), respectively. The pH responsiveness well as the temperature responsiveness of the shell structure was tested. The results showed that the lowest critical solution temperature (LCST) of the core-shell hydrogel is 43 ℃, with good temperature responsiveness in the range of 25–55 ℃, pH responsiveness from pH= 4 to pH= 13, and a short response time. From SEM, AFM, and BET, it can be concluded that the hydrogel has a rough surface and pore structure with a root mean square roughness value of 0.787 nm, a specific surface area of 1.3381 m²/g, and an average pore size of 4.0911 nm. FTIR and XRD can show that popcorn (PCP) is well-doped in the core-shell structure hydrogel, which also proves the existence of the core-shell structure. The design of the core-shell structure enhanced the stability performance of the shell temperature-sensitive hydrogel so that the retention rate of the sample was still 37% at 800 °C, and the water retention rate was still 80.7% after repeated immersion in distilled water 7 times, which has good prospects for agricultural and pharmaceutical applications. [Display omitted] • In this experiment, a static template polymerization method was used to synthesize the core-shell structure hydrogel, which is simple to operate and can be mass-produced. • The addition of popcorn enhances the porosity of the core layer hydrogel and facilitates the entry of water. • The preparation of the core-shell structure makes the hydrogel better adapted to the high temperature and high salt environment required for plant growth. • The preparation of core-shell structured hydrogels enhances the reusability and thermal stability of hydrogels. [ABSTRACT FROM AUTHOR]

Using salt-doped polystyrene- b -poly(2-vinylpyridine) star shaped block copolymer as a model, we show that the architecture of (A- b -B) n type multi-arm star block copolymers enhances the ordering of the block copolymers, enabling the generation of nanostructures with microdomain periods less than 10 nm. The influence of the arm number on the order-to-disorder transition temperature and molecular weight was systematically studied using small angle X-ray scattering. The configurational constraints placed on the chains by anchoring each block copolymer to a central junction point have a significant effect on the disorder-to-order transition behavior. In addition to an increase in the Flory-Huggins parameter ( χ ), block copolymers with multi-arm star shape chain architecture have a critical segregation strength ( χN ) C that decreases with arm number, opening a simple route to generate ordered nanostructures with periods below 10 nm. [ABSTRACT FROM AUTHOR]

The electronic structures of four Laves phase iron compounds (e.g. YFe 2 , ZrFe 2 , LuFe 2 and HfFe 2 ) have been calculated with a state-of-the-art full potential electronic structure code. Our theoretical work predicted that the magnetic moments collapse under hydrostatic pressure. This feature is found to be universal in these materials. Its electronic origin is provided by the sharp peaks in the density of states near the Fermi level. It is shown that a first order quantum phase transition can be expected under pressure in Y(Zr, or Lu)Fe 2 , while a second order one in HfFe 2 . The bonding characteristics are discussed to elucidate the equilibrium lattice constant variation. The large spontaneous volume magnetostriction gives one of the most important characteristics of these compounds. Invar anomalies in these compounds can be partly explained by the current work when the fast continuous magnetic moment decrease with the decrease of the lattice constant was properly considered. This work may be as a first insight into the rich world of quantum phase transition and Invar mechanism in these Laves phase compounds. [ABSTRACT FROM AUTHOR]

Superabsorbent composites (SACs) have great significance in environmental protection and agricultural production. However, it still remains a huge challenge to prepare SACs with the low-cost, strong water and nutrient retention capacity, slow evaporative loss and low water leakage. Herein, ablmoschus manihot gum-g-poly (acrylic acid-co-2-acrylamide-2- methyl-1-propanesulfonic acid)/microcrystalline cellulose (AMG-g-P(AA-co-AMPS)/MCC) SACs was prepared by radical polymerization method and further applied to prevent deep leakage of water in the soil. In which, the MCC extracted from wheat straw was selected as the skeleton to enhance the porous structure of SACs, and the AMG was used as the main moisture absorption material. Because the uniform distribution and abundant pore structure in AMG-g-P(AA-co-AMPS)/MCC, the water absorption of the SACs under the optimum synthetic conditions reached the equilibrium at 30 min in distilled water, and the optimum water absorption of SACs was 1240 g/g, 248 g/g and 80 g/g in distilled water, tap water and 0.9 wt% NaCl solution, respectively. In addition, SACs has good salt tolerance and pH stability. More importantly, the application of SACs in the soil can help improving the soil water retention and water holding capacity, and can reduce the water permeability in the soil effectively. Therefore, the SACs has broad application potential in agriculture. [Display omitted] • MCC was extracted from wheat straw to recycle this waste resource. • The AMG and MCC were used to synthesize the SACs as the raw material. • The SACs have outstanding soil water retention and water holding capacity. • The SACs also can reduce the water permeability in the soil effectively. [ABSTRACT FROM AUTHOR]

Electronic structures of Rh 2 TMSn (TM = Cr, Mn, Fe, Co, Ni and Cu) full Heusler compounds are calculated by the state-of-the-art electronic structure codes with the local density approximation aiming to understand the structure instability microscopically. The instability of the compounds can be explained by the band Jahn–Teller effect. The compounds can be categorized into two groups: In the first group, the density of states at the Fermi level are contributed mainly from Rh, while in the rest, both the Rh and TM atoms contribute. The high density of states at the Fermi level of the first group compounds may be smoothed and the highly symmetric phase is stable as found in experiments. The compounds in the second group tetragonally distort according to our calculation and was found in the experiments. [ABSTRACT FROM AUTHOR]

There have been a lot of reports on the preparation and properties of superabsorbent polymers, but there are still some problems and limitations in practical application. Therefore, a superabsorbent polymer (SAP) was synthesized by solution polymerization with tap water as reaction medium, acrylic acid and cross-linked polyvinylpyrrolidone (PVPP) as raw materials. The results of its performance and application show that the particle size was 0.425–0.85 mm, and the maximum water absorption rate of SAP in distilled water, tap water and 0.9% wt% NaCl solution was 2297 g/g, 333 g/g and 120 g/g, respectively. The water absorption rate can reach about 80% of maximum water absorption rate in 30 min. In addition, when the SAP mass addition amount was 0.56% and the particle size was 0.15–0.25 mm, the saturated moisture of sandy soil increased by 187%, the infiltration rate of sandy soil decreased by 96.7% and at 45 °C and 25 °C, the water evaporation rate of sandy soil decreased by 57.52% and 43.61%, respectively. So the material have a good application prospect in desertification and agriculture, and the way of preparation can be more effectively applied in practical production. [Display omitted] (a) The flowchart of SAP preparation; (b) The schematic diagram of the application of SAP in sandy soil; (c) The schematic diagram of cage effect. • The performance of SAP is improved from a new perspective that is reaction medium. • The addition of SAP can effectively increase the performance of soil. • The material has excellent water absorption and water retention. • The presence of ions would affect the effect of initiator and shorten the gel time of SAP. [ABSTRACT FROM AUTHOR]

In order to reduce the pollution of the bio-waste cabbage to the environment and achieve recycling of biological waste resources, synthesis of a novel superabsorbent polymer gel based on waste cabbage (CB) using two monomers AMPS (2-acrylamide-2-methyl-1-propane sulfonic acid) and AA (acrylic acid). And the synthesis conditions were optimized, such as the ratio of AMPS and AA, initiator content, and crosslinker content. And the water retention, salt resistance and repeated swelling performance were investigated too. The chemical structure thermal stability and microscopic appearance of the superabsorbent polymer gel were investigated by Fourier transform infrared spectroscopy (FTIR), Thermal gravimetric analysis (TGA) and Scanning electron microscope (SEM). The results showed that the novel superabsorbent polymer gel exhibits excellent water absorbency, which can absorb ultrapure water, distilled water, tap water and 0.9% NaCl solution are 1914 g/g, 1726 g/g, 306 g/g and 114 g/g, respectively. This is higher than in related studies 30%− 40% in distilled water, 60%− 70% in tap water and 10%− 20% in 0.9% NaCl solution. Therefore, this superabsorbent polymer gel showed a high swelling property and stable salt resistance. It has a broad application prospect. [Display omitted] • A novel SAP synthesized using waste cabbage. • Provides a new way to utilize this resource. • SAP with excellent water absorption performance. • Synthesis using a simple and effective method. [ABSTRACT FROM AUTHOR]

Abstract: Hexagonal barium ferrite thin films were fabricated by spin coating of precursors obtained by sol-gel methods onto sapphire (00l) faces. Citric acid and ethylenediaminetetraacetic acid (EDTA) were used to tune the morphology of the films. The films show texture with c-axis normal to the film plane as shown by the strong x-ray diffractions from the (001) plane with full width at half maximum of the rocking curves about 0.4°. The [100] direction of the film is parallel to the [110] direction of the sapphire. With the increase of the citric acid, the percentage of the acicular crystallites increased. EDTA can be used to produce films with the best texture where faceted grains were obtained. The maximum coercive force obtained was about 302 kA/m. [Copyright &y& Elsevier]

Abstract: Barium ferrite films were prepared by spin-coating of gels on sapphire (00 l) faces. Ethylenediaminetetraacetic acid was used to bind the metal ions. Thin films prepared by this method show faceted hexagonal grains with c-axis normal to the film plane and [110]sapphire ||[100]film. Needle-like grains, which have c-axis in the film plane, are minimized. Epitaxial growth of the film can be observed by the high resolution images. Reduction of the a and c-axis of the film compared with those of the bulk materials is confirmed both in real space and reciprocal space. Magnetic hysteresis loops were recorded in-plane and out-of-plane. The film shows uniaxial anisotropy as exemplified by branched domains with coercivity field of 87.6kA/m along the in-plane direction and of 302.5kA/m along the out-of-plane direction. [Copyright &y& Elsevier]

• Distribution of induced microwave current in Py film depends on its geometry. • SRE signal can be neglected at specific magnetic field angle and geometry for Py film. • Pure ISHE signal can be obtained directly in Py(20 nm)/Ta(10 nm) bilayer (40 μm × 8 mm). • Spin Hall angle value of Ta in Py/Ta bilayer is similar to that of some literatures. We present a method to directly obtain the pure inverse spin Hall effect (ISHE) signal without the spin rectification effect (SRE) signal in ferromagnetic metal(FM)/nonmagnetic metal(NM) bilayers. This method is based on a fact that the distribution of the induced microwave current is largely dependent on the geometries of the samples. The ISHE signal can be maximized through shaping the samples and tuning the magnetic field directions, while the SRE signal can be minimized below the detection limit. This provides also a fast and simplified method to measure the ISHE signal in a wide frequency range. The spin Hall angle of Ta in a Py/Ta bilayer is −0.027 ± 0.015 in a wide frequency range. [ABSTRACT FROM AUTHOR]

Metallic conduction layer produced by the irradiation of the SrTiO 3 surface is an intriguing phenomenon, where the process and mechanism of the insulating to conducting transition are still under debate. We have studied the influence of argon ion bombardment on the SrTiO 3 (STO) single crystal by X-ray Photoelectron Spectroscopy (XPS) and Photoluminescence (PL). The former demonstrated the existence of a lower oxidation state of Ti, which implied oxygen vacancies were present at the near-surface region. The latter showed that the oxygen damage enhanced with increasing irradiation time, and decreased by annealing in oxygen at high temperature. The in-situ electrical conductance measurement during irradiation revealed the correlation between the resistance of ion-irradiated STO and the irradiation time. The existence of sufficient amount of oxygen vacancies was proposed to be responsible to the insulator to metal transition during the process of irradiation. [ABSTRACT FROM AUTHOR]

Forage sorghum (FS; Sorghum bicolor (L.) Moench) is growing in popularity as an important forage crop replaced corn ( Zea mays L.) in semi-arid regions of the world. FS can further be divided into white midrib (WMR), green midrib (GMR) and brown midrib (BMR) populations based on the color of leaf midrib. Understanding expression of nutritive values in different FS populations is essential to the breeding and utilization of the new FS varieties with high quality. A field experiment was conducted in 2012 and 2013 in order to analyze the change regulation of nutritive values and compare the differences in photosynthetic indexes and anatomy parameters among WMR, GMR, BMR-6 and BMR-12 forage sorghum populations. The results showed that there were significant ( P < 0.05) differences in nutritive values and anatomy parameters between BMR and other FS populations whereas no differences ( P > 0.05) were observed in photosynthetic indexes. When compared with non-BMR populations (WMR and GMR), the mean ADL, NDF and ADF content of BMR populations (BMR-6 and BMR-12) were decreased respectively by 28.0%, 4.1% and 5.8% while the mean CP content was increased by 8.0% during the two years. Especially, BMR-12 populations had significantly ( P < 0.05) lower ADL content and higher CP content than that of BMR-6 based on their dynamic curve regression model. The nutritive values of forage sorghum populations were ranked as following order: BMR-12 > BMR-6 > GMR > WMR. In conclusion, the BMR populations, particularly BMR-12, had exhibited consistently higher nutritive values since joint stage (the average plant height was about 130 cm). This result further reinforces the advantages of BMR gene effect in populations and also will provide scientific data for rational utilizing BMR forage sorghum resources in practice. [ABSTRACT FROM AUTHOR]

Noble metal Pt with the face-centered-cubic structure is distorted to tetragonal and orthorhombic structures in order to mimic thin films grown on flexible substrates and bending. The electronic structures from the fully relativistic treatment of the kinetic terms were obtained and followed by projecting the extensive states into the localized Wannier orbitals with a minimum basis. The spin Hall conductivity (SHC) was then obtained with the help of the concept of the Berry curvature. We find that tensile strains in-plane can enhance the SHC while the compressive ones reduce the σ x y z component of the SHC. The variation of SHC can be as large as 8.6% for every 1% of the strains. Our work shows the possibility of tuning the SHC in metals, which can be utilized in spintronic devices. • The spin-to-charge conversion efficiency in Pt thin films can be enhanced by deformations. • The sensitivity of the spin Hall conductivity can be as large as 8.6% for every 1% of strains. • The underlying mechanism is the electronic band deformations. [ABSTRACT FROM AUTHOR]

The inverse spin Hall effect (ISHE) has been detected and separated from spin rectification effect (SRE) by inverting spin injection direction in metallic system. This work is based on the relation between the two effects and the spin injection direction: the sign of V ISHE changes because of the reversing direction of spin injection while the V SRE is independent on it. According to the different voltage signals before and after the spin injection inverted, the pure V ISHE and V SRE are calculated by utilizing the method of addition and subtraction. The signals can be separated in a wide range of frequency and power. [ABSTRACT FROM AUTHOR]

Abstract: Most nutrient solution studies on the interactions between silicon (Si) and cadmium (Cd) are short term. Here we reported a long-term experiment in which rice (Oryza sativa L.) was cultured for 105 days and harvested at four different growth stages to measure biomass accumulation and Cd uptake and distribution in shoots and roots. Exogenous Si increased shoot biomass by 61–238% and root biomass by 48–173% when the culture solution was free of Cd. When 2μmolL−1 Cd was added, Si supply increased shoot and root biomass by 125–171% and by 100–106% compared to the zero-Si treatment. Increasing the Cd concentration to 4μmolL−1 decreased the beneficial effects of Si on root and shoot biomass. Silicon supply decreased shoot Cd concentrations by 30–50% and Cd distribution ratio in shoot by 25.3–46%, compared to the treatment without Si supply. Additionally, lower Si supply or more serious Cd stress would lead to roots with bigger biomass and higher Si concentration. Energy-dispersive X-ray microanalysis showed that both Si and Cd accumulated synchronously in the border and middle of phytoliths of the shoots. We conclude that Si enhances plant growth and decreases Cd accumulation in shoots and thereby helps to lower the potential risks of food contamination. [Copyright &y& Elsevier]

• Ni, Co bimetallic selenides microspheres and BiSe nanosheets are synthesized. • The (Ni, Co)Se 2 demonstrate enhanced capacitive performances than pure NiSe 2 and CoSe 2. • A novel asymmetric supercapacitor based on all-metal selenides electrodes is proposed. • (Ni, Co)Se 2 //BiSe ASC possesses extended operating voltage and high energy density. Transition metal chalcogenides (TMCs) are considered as one of the most promising electrode materials for energy storage and conversion due to their unique intrinsic properties, but their electrochemical performance is largely limited by its poor conductivity. Thus, it is a feasible strategy to develop TMCs with hierarchical and ordered nanostructure to guide the electronic transport ways thereby enhance the electrical conductivity. Herein, a facile one-step solvothermal method has been designed and employed to synthesize uniform Ni, Co bimetallic selenides (termed as (Ni, Co)Se 2) microspheres and BiSe nanosheets. The (Ni, Co)Se 2 demonstrate enhanced capacitive performances of 106 mAh g−1 at 1 A g−1, which are more than two times of pure NiSe 2 and five times of pure CoSe 2 at the same current densities. Similarly, the BiSe nanosheets also exhibits a high specific capacity of 104 mAh g−1 at 1 A g−1 and good rate capability. Interestingly, a novel asymmetric supercapacitor is fabricated by using (Ni, Co)Se 2 nanospheres as the positive electrode and BiSe nanosheets as the negative electrode, which possesses extended operating voltage of 1.65 V, high energy density of 34.4 Wh·kg−1 at a power density of 373 W·kg−1, and an acceptable cycling stability of 85% capacity retention after 5000 cycles. A facile one-step solvothermal method has been designed and employed to synthesize uniform (Ni, Co)Se 2 microspheres and BiSe nanosheets. Based on high electrochemical properties and complementary operating voltage of (Ni, Co)Se 2 and BiSe materials, a novel (Ni, Co)Se 2 //BiSe asymmetric supercapacitor is fabricated from both metal selenides, which possesses extended operating voltage, high energy density, and good cycling stability. Image, graphical abstract [ABSTRACT FROM AUTHOR]

We measured the spin rectification effect and the inverse spin Hall effect in Nb-doped SrTiO 3 by pumping the spins from the ferromagnetic thin films into SrTiO 3. The spin injection is increased when the doping level is increased. However, the spin to charge conversion efficiency which is measured by the spin Hall angle decreases when Nb concentration is more than ∼ 0.02 wt%. We argued that it is because that the electrons contributed to the inverse spin Hall effect are from the d − orbitals of Nb instead of Ti beyond this concentration. Our work points to the importance of orbital occupations in the (inverse) spin Hall effect. We may explore controllable spin and charge interconversion in oxide spintronics. • The spin currents can be converted into the charge current in Nb doped SrTiO 3. • The conversion efficiency is a function of the doping levels • The underlying mechanism is the multiorbital nature of the d-electrons [ABSTRACT FROM AUTHOR]

Herein, a facile simultaneously activation and catalytic carbonization of the rare earth metal lanthanum-organic frameworks precursor strategy is developed to prepare a novel three-dimensional (3D) mesoporous interconnected carbon nanosheets (LMCN) with large surface area and high graphitization degree. During the synthesizing process, the ZnCl 2 and FeCl 3 act as activation and catalysis, respectively, to promote the formation of mesoporous carbon nanosheets with developed pores structure. The typical LMCN-1 prepared by high percentage of ZnCl 2 and FeCl 3 holds an interconnected mesoporous framework composed of ultrathin nanosheets and abundant porosity, displaying high specific capacitance of 251 F g−1 at a current density of 0.5 A g−1 and holding an excellent rate performance. Moreover, a symmetric supercapacitor assembled based on LMCN electrodes exhibits a prospective high energy density of 20.7 Wh kg−1 at a power density of 228 W kg−1 with a wide working voltage of 1.8 V in 0.5 M Na 2 SO 4 aqueous solution, along with the suitable capacity retention of 90.7% after 10,000 cycles. Image 1 [ABSTRACT FROM AUTHOR]

From a synthesized cobaltocenium-containing norbornene derivative, norbornene based copolymers with cobaltocenium cations are prepared by ring-opening metathesis polymerization (ROMP). The polymers can be cast into thin robust membranes. The membranes show morphology of disordered interconnected cobaltocenium domains. The high ionic conductivity suggests that such membranes are good candidates for anion exchange membranes. An efficient method to incorporate a cobaltocenium cation into polymers for anion exchange membranes is described. A cobaltocenium-containing norbornene derivative has been synthesized. It can be homopolymerized, or copolymerized with norbornene, by ring-opening metathesis polymerization (ROMP) with quantitative yields. The composition of the random copolymers can be precisely controlled by adjusting the feed ratio of the monomers. The resulting polymers can be cast into thin robust membranes. The morphology of the membranes is characterized by humidity controlled SAXS and TEM, showing disordered interconnected cobaltocenium domains. The high ionic conductivity suggests that such membranes are good candidates for anion exchange membranes. [ABSTRACT FROM AUTHOR]

• Anisotropical diffusion of incident atoms leads to non-uniform thickness of films. • Films on pyramid substrates have smaller M s but larger H c than that of on flat substrate. • Coercivities of all the films on mono-like cast silicons are highly angular dependent. • Surface structure of substrates dominantly affects the magnetic properties of films. The microstructure and magnetic properties of Ta/Ni 81 Fe 19 /Ta tri-layer thin films on three types of mono-like cast silicon substrates (flat, upright pyramid and inverted pyramid surfaces) were investigated. Results show that the surface topography structures of the films followed those of the substrates generally. But the thickness of the film on pyramid surface increases from the pyramid tip to the bottom. This is caused by the anisotropical diffusion of incident atoms/ions on the pyramid surfaces during the film growth process. The films on pyramid structured substrates have smaller saturation magnetizations but larger in-plane coercivity than that of on the flat substrate. This should be mainly caused by the non-zero angle between the magnetic field and the substrates as suggested by the angular dependent magnetic properties of the films. The hysteresis loops measured from in-plane to out-of-plane directions show that the coercivities of films on all the mono-like cast silicons are highly angular dependent. A further post-annealing of the films suggests that the magnetic properties of the films are dominantly determined by the surface microstructure of substrates instead of the fabrication conditions. The above results can help better integration of NiFe thin films on mono-like cast silicon based devices. [ABSTRACT FROM AUTHOR]