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The improvement of recrystallization texture and magnetic properties in grain-oriented electrical steel with trace Bi addition processed by strip casting process was studied in this study. Low casting temperature and sufficient liquid steel flow during strip casting process enabled relatively homogeneous distribution of Bi in the as-cast strip, which accelerated the precipitation during solidification and cooling process. As a result, relatively high density of duplex MnS + AlN, MnS and AlN was formed at grain boundaries and inside grain. Due to the synergistic effect of continuous precipitation and fragmentation of coarse precipitates during cold rolling, the number density of precipitates was increased and mean size was decreased along the processing route. High density of precipitates is attributed to severe inhomogeneous plastic deformation, which promoted the formation of high density in-grain shear bands during cold rolling and recrystallization Goss texture during annealing. Homogeneous microstructure with average grain size of ~ 11.6 μm, strong Goss texture with intensity of 2.5 multiples of random distribution, fine precipitates with number density of ~ 1.9 × 109 /cm2 and mean size of ~ 49 nm were formed after primary recrystallization annealing. Furthermore, grain-oriented electrical steel with Bi addition experienced complete secondary recrystallization of exact Goss grains during high-temperature annealing, which is attributed to beneficial optimization of Goss texture and strong inhibition effect, and superior magnetic induction B8 of 1.91 T was obtained. It is expected that this study paves a new way for fabrication of high-performance grain-oriented electrical steel.

Hypothesis Droplet impact on cylindrical surfaces is a widespread phenomenon observed in both nature and industrial applications. The wettability and size of the cylinders, and the initial impact velocity, are expected to influence the impact dynamics, such as generating different droplet morphology, spreading/retracting processes, and contact time, which could finally determine the anti-icing property of power transmission lines. Experiments A particle-based mesh-free numerical approach, many-body dissipative particle dynamics, is employed to study the impact dynamics. The cylinders with three different sizes and three types of wettability are modelled, and different initial impact velocities are set. Findings The simulations show the two liquid films (or lamellae) formed after impact can coalesce at the bottom site of a hydrophilic cylinder while they keep separate on hydrophobic and superhydrophobic cylinders. The maximum spreading diameter in the axial direction increases with the increase of impact velocity and cylinder size. Besides, the distribution of droplet detachment mode shows a strong dependence on initial impact velocity and cylinder size. In bouncing mode, the contact time increases with the increase of impact velocity while in dripping/bouncing mode, it has an opposite trend. The splashing angle is also observed to be dependent on the cylinder size.

This article reports microstructural characterization of as-cast and as-extruded Zn-Fe alloys and their mechanical and corrosion properties. Specifically, 1 wt.%, 2 wt.% and 3 wt.% Fe was added into the Zn matrix to form respective Zn-Fe alloys using casting and indirect hot extrusion processes. As the Fe content increased within the range of 1–3 wt.%, the mechanical properties of as-cast and as-extruded Zn-Fe alloys improved. The as-extruded Zn-Fe alloys showed superior mechanical properties of hardness, ultimate tensile strength (UTS) and elongation to failure (EL) to the as-cast Zn-Fe alloys of the same composition. Specifically, the UTS for as-extruded Zn-Fe alloys was 138–170 MPa, whereas the UTS for as-cast Zn-Fe alloys was 89–125 MPa. The corrosion properties of the as-extruded Zn-Fe alloys were investigated using the electrochemical and immersion methods. The corrosion rate of the as-extruded Zn-Fe alloys ranged from 0.015 mm/year to 0.210 mm/year.

In this article, a new technique to design a low-profile planar vortex beam generator is proposed based on microwave frequency selective surface (FSS), which is capable of generating orbital angular momentum (OAM) mode under circularly polarized incidence. Such OAM generator is composed of transmissive units distributed over a planar surface. Each unit cell, behaving as a spatial phase shifter, is composed of a stack of patches and grids separated by thin dielectric substrates. In order to reduce the thickness of the device, a rectangular patch is embedded in the middle layer to introduce an additional resonance. Compared to other resonant unit cells, this structure presents nearly perfect efficiency to convert circularly polarized incident wave to its cross-polarized component. A simple equivalent circuit model, composed of transmission lines coupled together with shunt capacitors and inductors, is presented to analyze this structure. The prototype of the proposed planar OAM generator operating in $x$ -band is designed, fabricated, and experimentally characterized. Good agreement is achieved between full-wave simulations and measurements. It is demonstrated that the generator can achieve an efficiency of 85% at 10.7 GHz with an overall thickness of $0.067\lambda _{0}$ .

This work reports a template-free wet chemical synthesis method for economical production of zinc oxide (ZnO) microrods by using an inexpensive polypropylene beaker as a reactor under atmospheric pressure. The morphology and crystal structure of the as-prepared ZnO microrods were investigated by scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and Raman scattering. Fourier-transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), Ultraviolet–visible (UV/Vis) spectroscopy and methylene blue photocatalytic degradation test were also conducted to study their physical and chemical properties. The results show that the as-prepared ZnO microrods have a hexagonal crystal structure. Under the optimal synthesis condition, they have a diameter of 0.8–2.6 μm and a length of 10–40 μm. Compared with commercial ZnO powders, the as-prepared ZnO microrods have a higher whiteness. Meanwhile, the as-prepared ZnO microrods have very low photocatalytic activity, indicating that they have good photostability and are unlikely to cause the photodegradation of polymers such as binders. As a result, they will be an excellent and economical white pigment with great potential in coating applications.

Membrane technology has aroused great attention for gas separations due to its high energy efficiency, small capital investment, easy and continuous operation. Mixed matrix membranes (MMMs) constructed from a continuous polymer phase and a dispersed filler phase offer new opportunities to achieve a breakthrough in fabricating high-performance membranes. Metal–organic frameworks (MOFs) have been regarded as potential fillers to boost the MMM separation performance. However, MOFs occasionally exhibit limited compatibility with the polymer matrixes owing to their partially inorganic structure and tendency of agglomeration in the membranes. Here, an interfacial design strategy is demonstrated by coating size-selective MOF cores with covalent organic framework (COF) layers to construct MOF@COF hybrids as fillers in MMMs for enhanced polymer-filler compatibility. The pure organic COF layers exhibit high affinity to the polymer matrix, thereby preventing the formation of nonselective interfacial voids and alleviating filler agglomeration. With the incorporation of only 5 wt% of MOF@COF fillers, the resultant MMM exhibits 48% and 79% enhancements in CO2 permeability and CO2/CH4 selectivity, respectively, with better operational stability compared to that of the pure polymeric membrane. These results reveal a novel filler design strategy for the tailored synthesis of high-performance MMMs for natural gas and biogas purification.

Four chiral AIE-active luminogens (AIEgens) containing tetraphenylethene (TPE) and one or two chiral glutamic moieties connected by thiourea were designed and synthesized. All AIEgens showed tunable aggregation-induced circularly polarized luminescence (AICPL) by adjusting the mono-/di-substituents of molecules or nanostructures of self-assemblies. The enantiotopic mono-substituted compounds (TPE-Glu) exhibited mirror-imaged AICPL signals with the maximal |glum| value of up to 0.02. Interestingly, the di-substituted cis- and trans-isomers showed reverse AICPL signals compared with those of mono-substituted ones. cis- and trans-isomers (TPE-DGlu) showed similar AICPL properties, whose signs of AICPL signals reversed while the water fraction (fw) was more than 80%. The SEM images of their self-assemblies indicated that the AICPL properties should have an intrinsic relation with their molecular structures or self-assembled nanostructures.

Understanding how we perceive differences in material compliance, or 'softness,' is a central topic in the field of haptics. The intrinsic elasticity of an object is the primary factor thought to influence our perceptual estimates. Therefore, most studies test and report the elasticity of their stimuli, typically as stiffness or modulus. However, many reported estimates are of very high magnitude for silicone-elastomers, which may be due to artifacts in characterization technique. This makes it very difficult to compare the perceptual results between the studies. The work herein defines a standardized and easy-to-implement way to characterize test stimuli. The procedure involves the unconstrained, uniaxial compression of a plate into cylindrical substrates 10 mm tall by 10 mm diameter. The resultant force-displacement data are straightforwardly converted into stress-strain data, from which a modulus is readily derived. This procedure was used to re-characterize stimuli from prior studies. The revised results from the validated method herein are 200-1,100 percent lower than modulus values either reported and/or approximated from stiffness. This is practically significant when differences of 10-15 percent are perceptually discriminable. The re-characterized estimates are useful in comparing prior studies and designing new studies. Furthermore, this characterization methodology may help more readily bridge studies on perception with those designing technology.

Although platelet-rich plasma (PRP) plays a significant role in the orthopedic clinical application, it still faces two major problems, namely, uncontrollable factors release, frequent preparation and extraction processes as well as the inconvenient form of usage. To overcome these shortcomings, freeze-dried PRP (LyPRP) was encapsulated into bioactive Col I hydrogel to induce osteogenic differentiation of rabbit bone marrow mesenchymal stem cells (rBMSCs). And PRP/Col І composite hydrogel was prepared as a control. Compared with Col І hydrogel, the introduction of platelets significantly improved the mechanical properties of hydrogels. Meanwhile, platelets were evenly distributed in the composite hydrogels network. The sustainable release of related factors in the composite hydrogels could last for more than 14 days to maintain its long-term biological activity. Further cell experiments confirmed that PRP and LyPRP could effectively alleviate the contraction of collagen hydrogel in vitro, and promote the adhesion, proliferation and osteogenesis differentiation of rBMSCs. The results of osteogenic gene expression indicated that the 10% LyPRP/Col І composite hydrogel could facilitate the early expression of BMP-2 and late osteogenic associated protein formation with higher expression of alkaline phosphatase and Osteocalcin (OCN). These results might provide new insights for the clinical application of 10% LyPRP/Col І composite hydrogel as practical bone repair injection.

Ethylene glycol (EG)-based hybrid nanofluids containing graphene oxide–silver nanosheets (GO–Ag) were simply prepared without using any surfactant. The graphene oxide–silver composites were characterized using X-ray diffraction analysis, transmission electron microscope, infrared and UV–visible spectroscopy. The stability of GO–Ag nanofluids was estimated by UV–visible spectroscopy. The GO–Ag/EG hybrid nanofluids has good stability without significant sedimentation for 60 days. A few thermophysical properties of GO–Ag/EG nanofluids with 0.1, 0.2 and 0.3 wt% nanosheets were analysed experimentally at different temperatures ranging from 20 to 50°C.

Summary Decades of artificial selection have significantly improved performance and efficiency of animal production systems. However, little is known about the microevolution of genomes due to intensive breeding. Using whole-genome sequencing, we document dynamic changes of chicken genomes under divergent selection on adiposity over 19 generations. Directional selection reduced within-line but increased between-line genomic differences. We observed that artificial selection tended to result in recruitment of preexisting variations of genes related to adipose tissue growth. In addition, novel mutations contributed to divergence of phenotypes under selection but contributed significantly less than preexisting genomic variants. Integration of 15 generations genome sequencing, genome-wide association study, and multi-omics data further identified that genes involved in signaling pathways important to adipogenesis, such as autophagy and lysosome (URI1, MBL2), neural system (CHAT), and endocrine (PCSK1) pathways, were under strong selection. Our study provides insights into the microevolutionary dynamics of domestic animal genomes under artificial selection., Graphical Abstract, Highlights • Directional selection reduces within-line but increases between-line genomic difference • Artificial selection tends to recruit preexisting variations of genes for fatness • Novel mutations contribute to the divergence of fatness under artificial selection • Genes involved in signaling pathways important to adipogenesis are under selection, Biological Sciences; Evolutionary Biology; Genetics; Genomics

The complex systems with edge computing require a huge amount of multifeature data to extract appropriate insights for their decision making, so it is important to find a feasible feature selection method to improve the computational efficiency and save the resource consumption. In this paper, a quantum-based feature selection algorithm for the multiclassification problem, namely, QReliefF, is proposed, which can effectively reduce the complexity of algorithm and improve its computational efficiency. First, all features of each sample are encoded into a quantum state by performing operations CMP and Ry, and then the amplitude estimation is applied to calculate the similarity between any two quantum states (i.e., two samples). According to the similarities, the Grover–Long method is utilized to find the nearest k neighbor samples, and then the weight vector is updated. After a certain number of iterations through the above process, the desired features can be selected with regards to the final weight vector and the threshold τ. Compared with the classical ReliefF algorithm, our algorithm reduces the complexity of similarity calculation from O(MN) to O(M), the complexity of finding the nearest neighbor from O(M) to OM, and resource consumption from O(MN) to O(MlogN). Meanwhile, compared with the quantum Relief algorithm, our algorithm is superior in finding the nearest neighbor, reducing the complexity from O(M) to OM. Finally, in order to verify the feasibility of our algorithm, a simulation experiment based on Rigetti with a simple example is performed.

Friction is a nonlinear effect that occurs in all mechanical systems which may cause limit cycles, tracking errors, and other undesirable effects. Traditional static friction models cannot characterize all the friction situations. In recent years, neural network (NN) technique has been widely used to approximate the nonlinear function. In this paper, a new method which combines radical basis function neural network (BRFNN) with beetle antennae search (BAS) algorithm for modeling friction in a robotic joint is proposed. Velocity, load, and temperature are considered as the three factors that influence the static friction. It is shown that the proposed BAS-RBFNN possesses better performance in terms of faster convergence rate and higher accuracy.

The positioning accuracy of a robot is of great significance in advanced robotic manufacturing systems. This paper proposes a novel calibration method for improving robot positioning accuracy. First of all, geometric parameters are identified on the basis of the product of exponentials (POE) formula. The errors of the reduction ratio and the coupling ratio are identified at the same time. Then, joint stiffness identification is carried out by adding a load to the end-effector. Finally, residual errors caused by nongeometric parameters are compensated by a multilayer perceptron neural network (MLPNN) based on beetle swarm optimization algorithm. The calibration is implemented on a SIASUN SR210D robot manipulator. Results show that the proposed method possesses better performance in terms of faster convergence and higher precision.

In our ability to discriminate compliant, or ‘soft,’ objects, we rely upon information acquired from interactions at the finger pad. We have yet to resolve the most pertinent perceptual cues. However, doing so is vital for building effective, dynamic displays. By introducing psychophysical illusions through spheres of various size and elasticity, we investigate the utility of contact area cues, thought to be key in encoding compliance. For both active and passive touch, we determine finger pad-to-stimulus contact areas, using an ink-based procedure, as well as discrimination thresholds. The findings indicate that in passive touch, participants cannot discriminate certain small compliant versus large stiff spheres, which generate similar contact areas. In active touch, however, participants easily discriminate these spheres, though contact areas remain similar. Supplementary cues based on stimulus rate and/or proprioception seem vital. One cue that does differ for illusion cases is finger displacement given a volitionally applied force.

Both humans and objects can emit infrared (IR) wavelengths which generate thermal emissions that can be detected with an IR camera. Therefore, highly IR reflective materials have been the subject of interest recently, for example, in achieving IR stealth. In this work, IR reflective coatings on polyester fabric in the form of a titanium dioxide/copper/titanium dioxide (TiO2/Cu/TiO2; TCT) sandwich-like structure are fabricated by using magnetron sputtering. The coated fabric samples are then examined by using an energy dispersive X-ray detector, a scanning electron microscope and an X-ray diffractometer. The reflection of IR wavelengths which range from 8 to 14 µm of the TCT coated fabric is evaluated. The bending stiffness, and mechanical and adhesion strengths of the coated fabric samples are also investigated. The results show that the TCT sandwich-like structure on the polyester fabric sputtered for 30 min with Cu which results in a Cu film of 200 nm in thickness is observed to have the maximum reflection of IR wavelengths. The color of the TCT coated polyester fabric samples sputtered for 5, 10, 20, and 30 min with Cu is green, yellow, brown and purple, respectively. The TCT coated fabric therefore has potential applications as IR protection textiles for military purposes.

In this paper, the microstructure and properties of as-cast Cu-Y-Zr alloys with different Zr content were studied in order to investigate whether the precipitates in copper alloys would interact with each other by adding Y and Zr simultaneously. As-cast Cu-0.5Y-xZr (wt.%, x = 0.05 and 0.1, nominal composition) alloys were prepared by vacuum melting in this study. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and transmission electron microscopy (TEM) were used to observe the microstructure of the alloys. The mechanical properties of the alloys were tested by universal material testing machine at room temperature. The effects of Zr content on the microstructure and mechanical properties of the alloys were explored. As shown by the research results, in the as-cast Cu-0.5Y-xZr (wt.%) alloys, the precipitated phase was the Cu5Y/Cu5Zr phase and ranged from 10 nm to 70 nm in size, when the Zr content increased from 0.05 wt.% to 0.1 wt.%, both the tensile strength and elongation rate of the alloys increased, when the Zr content was 0.1 wt.%, the tensile strength was 225 MPa and the elongation rate was 22.5%.

Boundary condition in dissipative particle dynamics system is a challenging problem since the emergence of this promising numerical method. Here, we present a quite simple boundary condition which takes the distribution of solid particles, minimal distance between fluid and solid particles, and the velocity of fluid particle into consider. By generating an attempered velocity, the approaching fluid particles are forced back into fluid area softly. This boundary condition is good at preventing penetration and keeping the interfacial properties and meanwhile easy to implement. Three representative cases are studied to show its advantages in simulating solid/fluid systems.

In the present study, a numerical simulation of droplets wetting on surfaces with chemically heterogeneous stripes was performed by using many-body dissipative particle dynamics (MDPD). The effects of the ratio of periodicity width w to the contact length L of a 2D droplet (i.e., w / L ) on the contact angle were investigated to analyse the validity of Cassie-Baxter equation. With the simulated process about the droplets wetting on chemically heterogeneous surfaces, the results show that when the ratio is smaller than 0.118 (2/17), the numerical values of the static contact angles are in good agreement with the prediction of the Cassie-Baxter equation for droplets wetting on chemically heterogeneous substrates formed by alternative stripes in mesoscopic scale. While for the ratio larger than 0.118, the Cassie-Baxter equation will not be appropriate to accurately predict the apparent contact angles. This ratio may be considered as the critical value to apply Cassie-Baxter equation on these types of chemically heterogeneous substrates. Furthermore, a comparison between rear dynamic contact angles for different ratios was found in accordant with expected.

Samples of the woven cotton fabric are first modified with a continuous polyvinyl alcohol (PVA) thin film by using the padding method and then coated with copper (Cu), titanium and stainless steel (SS) respectively, by using a magnetron sputtering system. The samples are then systematically characterized with energy dispersive X-ray spectroscope, X-ray diffractometer, and scanning electron microscope. The infrared (IR), ultraviolet and electromagnetic interference shielding properties of the samples are also well investigated, as well as the contact angle (CA), light transmittance and conductivity. The results show that pretreatment with PVA can enlarge the light transmittance of cotton fabric. The metal coated PVA/cotton samples show a better performance in electro-conductivity although there is a little bit decrease in other properties compared to the metal coated cotton fabric. The Cu coated PVA/cotton sample has a higher electromagnetic interference shielding effectiveness of − 30 dB, a lower electrical resistivity of 5.49 × 10−6 Ω m, while the Cu coated cotton sample presents a higher IR reflection rate about 25%, the SS coated cotton fabric show a higher CA of 128.2 °and UPF of 117.647. The excellent properties of the coated cotton fabric mean that it is a promising electro-conductive and multi-shielding textile for smart applications.

Strip-cast grain-oriented 4.5% Si steel was produced by short-term isochronal secondary annealing (15 min) and isothermal annealing (1000 °C) under hydrogen atmosphere. The relationship between the evolution of grain structure and magnetic properties was elucidated. It was observed that during isochronal annealing, abnormal grain growth occurred followed by normal grain growth with the increase of annealing temperature. Additionally, decreasing the primary annealing temperature accelerated the isochronal annealing kinetics, and near complete abnormal grain growth with optimal magnetic properties was obtained at lower temperature. Furthermore, during isothermal annealing, abnormal grain growth successfully occurred and magnetic properties were continuously improved with the increase of annealing time. The optimal magnetic properties were superior to those of isochronal annealing because of sharper secondary Goss texture and reduced retention of second-phase particles. The grain-oriented 4.5%Si steel in the present study indicated superior properties and better workability than the previously reported non-oriented 6.5%Si steel. Thus, grain-oriented 4.5%Si steel produced by short-term secondary annealing can potentially replace non-oriented 6.5%Si steel.

The competitiveness of reduced graphene oxide (GO) based composite can be significantly improved when the raw material of GO become the low-cost microcrystalline graphite mine. Herein, we first successfully fabricate high-quality microcrystalline graphite GO (MGO) with small size 3 O 4 @C/PrMGO composite is simply constructed by using porous reduced MGO (PrMGO) to support carbon coated Fe 3 O 4 nanoparticles (Fe 3 O 4 @C NPs). The Fe 3 O 4 @C/PrMGO composite exhibits high reversible capacity and excellent cyclic stability that a high reversible capacity of 1216 mA h g −1 is received after 392 cycles at 100 mA g −1 . Meanwhile, the composite possesses high rate retentions, superior structural and cycling stability, which are further revealed by rate test, SEM and EIS analyses. The significant advantages of Fe 3 O 4 @C/PrMGO composite (low cost, facile operation and high electrochemical performances) endow the composite to be practically promising anode material for next-generation LIBs. This research supplies a new strategy to fabricate low-cost and high performances MGO-based anode materials.

Ultrathin mixed matrix membranes (MMMs) containing two-dimensional (2D) fillers are highly sought recently due to their good performance in gas separations. Here we report the preparation of PIM-1 based ultrathin MMMs containing 2D metal-organic framework (MOF) nanosheets using spin coating method. The lamellar structure of the 2D layered MOF filler (copper 1,4-benzenedicarboxylate nanosheets, CuBDC-ns) enlarges the contacting area between fillers and the polymer matrix, leading to the formation of dense MMMs. The centrifugal force generated during the spin coating process helps to horizontally align these CuBDC-ns, increasing the gas diffusion resistance across the membrane. The influence of membrane thickness and filler content on the separation performance of CO2/CH4 mixture is examined and discussed. Optimizing membrane thickness and filler content results in a 660 nm thick ultrathin MMM comprising 10 wt% CuBDC-ns, which exhibits a CO2/CH4 selectivity of 15.6 and CO2 permeance as high as 407 GPU, surpassing other PIM-1 based membranes. Besides, the long term stability test shows that the prepared ultrathin MMMs are stable up to 100 h. These results demonstrate that the ultrathin MMMs reported in this study are excellent candidates for CO2/CH4 separation, with potential applications in natural gas purification and biogas upgrading.

Rapid and highly efficient treatment of acid mine drainage (AMD) is still challenging due to the low pH and high metal concentrations in it. This research focuses on a novel treatment method of AMD using direct contact membrane distillation (DCMD) and photocatalysis to recover water and utilize iron. In the DCMD process without pretreatment, the flux decreased by 93.38%. If pretreated by adding sodium oxalate, scale formation potential was effectively mitigated due to the removal of calcium and complexing of iron. For the treatment of the pretreated AMD (PAMD), 60% of water was recovered in the DCMD process with the flux decrease of 22%. The concentrate obtained from the DCMD process demonstrated high photocatalytic activity in the methylene blue (MB) degradation in an aqueous solution. In addition, the Fe (III)-oxalate complexes in the concentrate were reduced to insoluble Fe (II)-oxalate with visible light irradiation, which could be separated by sedimentation and used as a Fenton catalyst. Hence, this novel method exhibits great advantages on effectively inhibiting DCMD membrane fouling during AMD treatment, producing high-quality distillate with low conductivity, and realizing near zero-discharge of AMD.

Thin film composite membranes (TFCMs) have displayed attractive CO2 capture performance, in which a critical gutter layer with small transport resistance is needed to prevent the penetration of the top separation layer into the bottom porous support for realizing high CO2 permeance. However, traditional and recently developed gutter layer materials face some issues such as physical aging, thickness-dependent permeability, instability, or poor compatibility. Herein, wholly organic, orientated, two-dimensional covalent organic framework (COF) films, for the first time, are used as the novel gutter layers due to the ideal pore size, intrinsic porosity, small transport resistance, good compatibility with polymer matrix, good anti-aging capability and high stability. Commercial or photo-initiated crosslinked polymer can be deposited compatiblely on the COF gutter layer with a thickness as thin as 55 nm, an ultrathin thickness that traditional gutter layers are challenging to attain. As a result, one optimized TFCM realizes high CO2 capture performance with CO2 permeance of 1843 gas permeation units (GPU) and CO2/N2 separation selectivity of 28.2, which displays unique advantages over other gutter layer-based TFCMs and meets the performance target for CO2 capture (CO2 permeance > 1000 GPU, CO2/N2 selectivity > 20).

Droplet impact on non-flat surfaces is a common phenomenon, further understandings of this phenomenon can guide a rational design of relevant applications in daily life. The present work numerically studies droplet impact on superhydrophobic solid spheres of different sizes by using many-body dissipative particle dynamics. The simulation results indicate that the time-dependent wrapping angle highly relies on the initial impact velocity and solid sphere size. Four spreading types, bouncing, wrapping, dripping, and bouncing & dripping, can be identified under different impact conditions. It is found that bouncing type prefers to happen at low impact velocity while dripping type is more likely to happen at high impact velocity. Further, on a solid sphere with small size, the dripping type happens at a large range of impact velocity while bouncing type occupies the large range on sphere surface with large size. The contact time is found much shorter for dripping cases than bouncing cases for all sphere sizes.

Copper (Cu) is deposited as a film onto polyamide-6 (PA-6) fibers with a magnetron sputtering technology by using a self-assembly machine with a winding unit. The Cu coated PA-6 fibers are characterized by using surface profiler, X-ray diffractometer and scanning electron microscope. The electrical conductivity, Raman spectra, tensile strain and tensile stress of Cu coated PA-6 fibers are also systematically investigated. The results show that the mean value of the electrical conductivity of Cu-coated PA-6 fibers increases with decrease of winding speeds and reaches 7.03 × 10−5 Ω m at 4.7 cm/min. The Cu coated PA-6 fibers are used as electric wires to light the LEDs. The Raman characteristic peak of PA-6 fiber in the spectra is influenced after coating. With the drop of winding speed, the tensile strain and tensile stress of coated PA-6 fibers both decrease after Cu deposition.

This is a successive study to our previous study published in this journal. In the present study, a further numerical study on the penetration of a droplet into non-wetting capillaries is carried out by using many-body dissipative particle dynamics (MDPD). The simulation results show the outer (outside of the capillary) and inner (inside of the capillary) curvatures of the droplet can cause two Laplace pressures. The difference between these two pressures forms a net pushing force which directly drives the droplet flowing into the non-wetting capillary. We give a detailed analysis on how the outer and inner curvatures change during the penetration process. To further show the effect of the Laplace pressure difference on the droplet movement, we also simulate a new droplet/capillary/film system. In this system, the droplet and liquid film are placed at both ends of a prefilled capillary. It is very interesting to find that the droplet penetrates even faster in lyophobic capillaries over lyophilic ones, and the spontaneous penetration does not pose any wettability restriction which is different from previous study in literatures. The present work is expected to provide new ideas for designing microfluidics or nanofluidics devices by utilizing the driving force from the droplet itself.

The proton exchange membrane fuel cell (PEMFC) is an innovative technology for the realization of next-generation power sources, in which a polymer or blend membrane is used to separate the fuel from the oxidant and to transport protons. Although a variety of membranes have been synthesized and characterized by both experimental and molecular simulation methods in the past few decades, the underlying microscopic molecular mechanism is still unclear. In this article, a blend membrane composed of SPEEK and PVDF is investigated by dissipative particle dynamics (DPD) and molecular dynamics (MD) simulation methods. The results show that the blend of SPEEK and PVDF has preferable compatibility as the sulfonation degree is about 50%, and the compatibility is improved further by adding 10% PSSA grafting additive. For both 90/10 and 80/20 blending proportions, SPEEK and PVDF-g-PSSA mixed fairly well, and a proton exchange channel network is observed. What's more, as the PVDF-g-PSSA content increases from 5% to 20%, the hydrophilic clusters, which consist of sulfonate groups, water molecules and hydronium ions, are formed and aggregate inside the SPEEK membrane. In addition, the transport properties and proton conductivities of the blend membrane are also significantly improved by the increase of the content of PVDF-g-PSSA.

Grains of Al–1Si(wt%) alloy were refined by accumulative continuous extrusion forming (ACEF). Electron backscatter diffraction and transmission electron microscopy were used to analyze the microstructure evolution of the Al–1Si(wt%) alloy. The grain size of the alloy decreased from 54.36 to 2.59 μm after four passes of ACEF. The grain refinement was attributed to continuous dynamic recrystallization (CDRX). The enhanced effect of nanosized precipitates on CDRX was pronounced. Nanosized eutectic Si precipitates retained a high density of dislocations in the alloy by promoting their generation and pile-up, resulting in an increase in the driving force for CDRX and a consequent promotion of grain refinement. After 4 ACEF passes, the tensile yield strength of the alloy at room temperature increased from 102 MPa to 117 MPa. Further, the elongation of the alloy at room temperature decreased from 38 to 17 % after 3 ACEF passes and subsequently increased to 23 % after 4 ACEF passes.

Mutational inactivation of ATRX (α-thalassemia mental retardation X-linked) represents a defining molecular alteration in large subsets of malignant glioma. Yet the pathogenic consequences of ATRX deficiency remain unclear, as do tractable mechanisms for its therapeutic targeting. Here we report that ATRX loss in isogenic glioma model systems induces replication stress and DNA damage by way of G-quadruplex (G4) DNA secondary structure. Moreover, these effects are associated with the acquisition of disease-relevant copy number alterations over time. We then demonstrate, both in vitro and in vivo, that ATRX deficiency selectively enhances DNA damage and cell death following chemical G4 stabilization. Finally, we show that G4 stabilization synergizes with other DNA-damaging therapies, including ionizing radiation, in the ATRX-deficient context. Our findings reveal novel pathogenic mechanisms driven by ATRX deficiency in glioma, while also pointing to tangible strategies for drug development., ATRX deficiency is linked to genomic stability in cancer cells. Here, the authors show that ATRX inactivation induces G-quadruplex formation, leading to genome-wide DNA damage, and the use of G-quadruplex stabilisers can be exploited therapeutically in ATRX deficient gliomas.

Robot calibration is used to improve the accuracy of the kinematic model to achieve the higher positioning accuracy within the workspace. Due to some nongeometrical reasons such as joint and link flexibility, the errors are unevenly distributed in the workspace. In this case, it is difficult for the existing methods used to improve the absolute positioning accuracy to achieve good results in each region, especially for robots with large self-weights. In this paper, a novel calibration method is proposed, which deals with joint deflection dependent errors to enhance the robot positioning accuracy in the whole workspace. Firstly, the joint angle workspace is divided into several local regions according to the mass distribution of the robot. Then, its geometric parameters are modeled and identified using the Denavit–Hartenberg (DH) model in each region and in the whole workspace separately. Since the nongeometric error sources are difficult to model correctly, an artificial neural network (ANN) is applied to compensate for the nongeometric errors. Finally, the experiments using an 8 degree-of-freedom (DOF) engineering robot are conducted to demonstrate the validity of the proposed method. The combination of the joint angle division and ANN could be an effective solution for the robot calibration, especially for one with a large self-weight.

This study investigated whether and to what extent does the High-Speed Railway (HSR) affect city-level housing prices. With the data of HSR operation and housing prices from 285 cities from 2009 to 2017, the paper aimed to estimate the quantitative relationship between HSR and city-level housing prices and exploited city and regional dummy variables to assess the disparities between regions, followed by the economic effects between typical city pairs. Our findings were as follows: (1) The introduction of HSR leads to a 13.9% increase in city-level housing prices, and the figures for national central cities and regional central cities were 31.7% and 19.6%, respectively, (2) regional imbalance was mitigated with the development of the HSR, and some central cities in underdeveloped regions were stimulated with regard to housing price growth, (3) siphon effects and diffusion effects were observed in megacity&ndash, small city pairs, while synergistic effects often lay in megacity&ndash, megacity pairs, and such effects all tended to be more significant with increases in the number of HSR lines and a drop in the travel time.

Overhead transmission lines are the most key component in power transmission systems, the bare transmission lines with stranded conductors are the main type for long-range power transmission. However, the long range makes the transmission lines easily be affected by rain icing problem in winter or cold regions, therefore the understandings of how the rain droplet interacting with surfaces of this kind of transmission lines are significant. By using many-body dissipative particle dynamics, the present work simulates the droplet impact on the stranded conductors with varying surface properties, such as surface wettability, number of strands, and twist pitch. The simulation results show that hydrophilic surfaces can retain most of the liquid while the superhydrophobic ones can repel most liquid after impact. A large number of strands, which means a large size of grooves, will force the liquid to flow along the grooves after impact. In this circumstance, grooves on surfaces with short twist pitch can guide the liquid to flow to a more downward direction, while grooves on surfaces with long twist pitch can guide the liquid flow closer to the axial direction of the transmission line and retain more liquid on the surface after impact. Besides, for bouncing cases, longer twist pitch can cause longer contact time.

Covalent organic frameworks (COFs) present a large group of crystalline porous polymeric materials, which are formed with organic building blocks by strong covalent bonds. They have great potential in energy, environment, and biotechnology areas due to their high surface areas, tunable pore size distribution, and versatile functionality. However, they are largely synthesized in powder form only. The recent 3D printing technology requires the addition of binders. For the targeted applications in gas separation and adsorption, the existence of any binders not only increases the cost, but also reduces the surface area of the active materials and adds on dummy weight, which is especially harmful to functional porous materials where the retention of surface functionality and surface area is paramount. Herein, we report a binder-free, 3D printing process for COF materials (SNW-1 and ATFG-COF), capable of producing free-standing, crack-free 3D COF monoliths by the control of the solvent choices and their diffusion and evaporation among the different parts of the monoliths. Compared to SNW-1 with F127 binder added, the binder-free 3D monolith shows a larger surface area of 794 m2/g, which is similar to SNW-1 powder. The higher CO2 adsorption and CO2/N2 sorption selectivity compared to monoliths made with F127 binder further demonstrate the advantage of binder-free, 3D printing technology applied to COFs.

Water-stable zirconium metal-organic frameworks (Zr-MOFs) such as the UiO-66 series have been recently identified as promising materials for polycrystalline membranes. However, the reliance of such membranes on rigid and expensive ceramic substrates with low packing density has greatly limited their wider applications. Herein, we report polycrystalline UiO-66(Zr)–NH2 membranes grown on cheap and flexible carbon cloth by in situ solvothermal synthesis. The membranes possess sub-micron thicknesses with a certain flexibility and angular bend tolerance up to 10°. In addition, these membranes exhibit great separation performance in organic solvent nanofiltration (OSN) because of their excellent solvent resistance, with above 99.8% dye rejection and high flux for dichloromethane (ca. 0.17 kg m−2 h−1 bar−1). Our study paves the way toward the development of polycrystalline Zr-MOF membranes for challenging liquid separations.

The grain of an Al 0.2Er alloy (wt%) was refined by accumulative continuous extrusion forming (ACEF). Microstructure of the Al Er alloy subjected to ACEF was investigated through electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The results revealed that the formation of ultra-fine grains results from a type of continuous dynamic recrystallization (CDRX) that is induced by large strains. With the accumulation of strain, LAGBs gradually introduced and transformed into HAGBs, which leads to an increase in the average orientation angle. The micro-grain alloy is refined through repeated passes of the continuous extrusion forming process and the average grain size of the Al 0.2Er (wt%) alloy decreased from 26.01 μm to 1.3 μm in four passes. The Al 0.2Er (wt%) alloy had a smaller average grain size than that of pure aluminum. The formation of precipitates in Al Er alloy can stimulate the nucleation of CDRX by increasing the local strain energy and slow the growth of recrystallization grains by limiting grain boundary migration that causing grain refinement.

In the present study, the spontaneous uptake of droplets into non-wetting capillaries was simulated by using many-body dissipative particle dynamics. The simulated results show that the droplets undergo a spontaneous uptake even for a non-wetting capillary. In contrast to the liquid in a reservoir in which the direction of liquid spontaneous movement in the capillary depends on the wettability, the moving direction of droplets in the capillary relies not only on the surface wettability but also the radius of the droplets. We give an explanation from the viewpoint of force balance. Our results demonstrate that capillary force could be used to drive liquid in microfluidics.

Because of their uniform yet tunable pore size and rich functionality, metal-organic frameworks (MOFs) have attracted huge interests as membrane materials. However, the relatively weak stability limits their applications in liquid separation. Herein, we report the fabrication of polycrystalline rare-earth MOF membranes (Sm-DOBDC) supported on alumina hollow fiber, exhibiting excellent water stability. Using these membranes for the dehydration of 5 wt% water/ethanol feed solution at 323 K, a total flux of 786.4 ± 33.7 g m−2 h−1 and a 99.8 ± 0.2 wt% water concentration in the permeate can be achieved, with a high separation factor of above 9481. In addition, in-situ healing ability of this membrane is demonstrated by treating with spent reaction solution, shedding light on the practical applications of polycrystalline MOF membranes in liquid separation.

The droplet impact on groove-patterned surfaces is numerically studied. Two types of groove-patterned surfaces, one is modelled with uniform grooves and ridges, another is modelled with different grooves and ridges on the two halves of the substrates. The simulation results show that for the droplet impact on substrates with uniform length ratio (ratio of ridge width to droplet radius), low impact velocity cannot cause obvious anisotropic spreading and receding, while high velocity can, and the maximum spreading diameters at both directions parallel and perpendicular to the grooves witness a decrease with the increase of the length ratio. For droplet impact on substrates with different length ratio, the unsymmetrical spreading and receding of the droplet in the direction perpendicular to the grooves can also be observed. The understandings obtained in this study could provide ideas for relevant applications, such as building materials with self-cleaning and anti-icing properties in civil engineering.

This study presents a simple one-step hydrothermal method to produce a new Mn/Al double oxygen sludge-derived biochar (MA-SBC) from dewatered sewage sludge, which is used for enhancing phosphate removal. Characterization results showed that a cubic spinel-type MnAl2O4 was successfully embedded in the matrix of MA-SBC. A series of systematically designed batch experiments were performed to evaluate the effect of initial pH, contact time, and initial phosphate concentration on the adsorption behavior of MA-SBC. The results revealed that the adsorption process of phosphate onto MA-SBC conformed to a pseudo-second-order model, and the rate of adsorption was mainly dominated by a mechanism of film diffusion. A Langmuir isotherm model accurately described the adsorption isotherm, with a maximum adsorption amount of 28.20 mg-P/g at 298 K (50 mg/L for the initial phosphate solution), which was more efficient than those of previously reported composites. Moreover, X-ray diffraction, Fourier transform infra-red and X-ray photoelectron spectroscopy analyses proved that the mechanism of phosphate removal from aqueous media were the inner-sphere surface complexation reaction of phosphate with ≡M-OH groups and a subsequent precipitation reaction of aluminum phosphate. Cycle stability and metallic ion leaching tests demonstrated the strong stability of MA-SBC. In general, the results of this research suggest that MA-SBC has potential applicability for removing phosphate from aqueous media as an alternative, eco-friendly, and economic adsorbent for environmental restoration.

In this paper, we review the generation of vortex beams carrying orbital angular momentum in the microwave domain. We firstly present the theory of Laguerre–Gaussian beams where it is demonstrated that they carry such type of momentum. We further provide an overview of the classical methods used to generate orbital angular momentum vortex beams, which rely on two main methods; plane wave to vortex wave conversion and direct generation using radiating antennas. Then, we present recent progress in the physics of metasurfaces devoted to the generation of vortex beams with a discussion about reflective and transmissive metasurfaces for plane wave to vortex wave conversion as well as methods to reduce the intrinsic divergence characteristics of vortex beams. Finally, we conclude on this rapidly developing research field.

An integrated experimental and computational approach has been adopted to investigate the formation mechanism of intermetallic compounds (IMCs) in dissimilar Al-Cu joints processed by vaporizing foil actuator welding (VFAW). Aiming to understand the formation of IMCs and their transition, the present work employed first-principles calculations of thermodynamic properties as a function of temperature and pressure together with diffusivities of Al and Cu from the literature. Agreeing with experimental observations, the predicted IMC formation sequence in the low-energy welding region is as follows. θ-Al2Cu forms first due to the fast diffusivity of Cu in the Al-matrix. θ-Al2Cu then transforms to η2-AlCu because of the fast diffusivities of Al/Cu in θ-Al2Cu. In the high-energy welding region, the stable γ1-Al4Cu9 and the metastable θ’’-Al3Cu are also formed in addition to the aforementioned θ-Al2Cu and η2-AlCu. η2-AlCu and considerable γ1-Al4Cu9 are the major phases in the high-energy welding region. The present approach, combining experiments and calculations, is proven to be a practical way to understand non-equilibrium metallurgical processes, as demonstrated through the study of VFAW Al-Cu joints. Keywords: Vaporizing foil actuator welding (VFAW), Al-Cu intermetallic compounds, Thermodynamic properties, Diffusion, First-principles and phonon calculations

Friction stir scribe (FSS) welding as a recent derivative of friction stir welding (FSW) has been successfully used to fabricate a linear joint between automotive Al and steel sheets. It has been established that FSS welding generates a hook-like structure at the bimaterial interface. Beyond the hook-like structure, there is a lack of fundamental understanding on the bond formation mechanism during this newly developed FSS welding process. In this paper, the microstructures and phases at the joint interface of FSS welded Al to ultra-high-strength steel were studied using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that both mechanical interlocking and interfacial bonding occurred simultaneously during the FSS welding process. Based on SEM observations, a higher diffusion driving force in the advancing side was found compared to the retreating side and the scribe swept zone, and thermally activated diffusion was the primary driving force for the interfacial bond formation in the scribe swept region. The TEM energy-dispersive X-ray spectroscopy (EDXS) revealed that a thin intermetallic compound (IMC) layer was formed through the interface, where the thickness of this layer gradually decreased from the advancing side to the retreating side owing to different material plastic deformation and heat generations. In addition, the diffraction pattern (or one-dimensional fast Fourier transform (FFT) pattern) revealed that the IMC layer was composed of Fe2Al5 or Fe4Al13 with a Fe/Al solid solution depending on the weld regions.

Image hallucination and super-resolution have been studied for decades, and many approaches have been proposed to upsample low-resolution images using information from the images themselves, multiple example images, or large image databases. However, most of this work has focused exclusively on small magnification levels because the algorithms simply sharpen the blurry edges in the upsampled images - no actual new detail is typically reconstructed in the final result. In this paper, we present a patch-based algorithm for image hallucination which, for the first time, properly synthesizes novel high frequency detail. To do this, we pose the synthesis problem as a patch-based optimization which inserts coherent, high-frequency detail from contextually-similar images of the same physical scene/subject provided from either a personal image collection or a large online database. The resulting image is visually plausible and contains coherent high frequency information. We demonstrate the robustness of our algorithm by testing it on a large number of images and show that its performance is considerably superior to all state-of-the-art approaches, a result that is verified to be statistically significant through a randomized user study., 13 pages, 8 figures, submitted to IEEE Transactions on Multimedia, under revision

Recently, deep learning methods have made a significant improvement in compressive sensing image reconstruction task. In the existing methods, the scene is measured block by block due to the high computational complexity. This results in block-effect of the recovered images. In this paper, we propose a fully convolutional measurement network, where the scene is measured as a whole. The proposed method powerfully removes the block-effect since the structure information of scene images is preserved. To make the measure more flexible, the measurement and the recovery parts are jointly trained. From the experiments, it is shown that the results by the proposed method outperforms those by the existing methods in PSNR, SSIM, and visual effect., Comment: Accepted by neurocomputing in 2018

Detection of volatile organic compounds (VOCs) at parts-per-billion (ppb) level is one of the most challenging tasks for miniature gas sensors because of the high requirement on sensitivity and the possible interference from moisture. Herein, for the first time, we present a novel platform based on a hybrid photonic cavity with metal-organic framework (MOF) coatings for VOCs detection. We have fabricated a compact gas sensor with detection limitation ranging from 29 to 99 ppb for various VOCs including styrene, toluene, benzene, propylene and methanol. Compared to the photonic cavity without coating, the MOF-coated solution exhibits a sensitivity enhancement factor up to 1000. The present results have demonstrated great potential of MOF-coated photonic resonators in miniaturized gas sensing applications.

Conventional compressive sensing (CS) reconstruction is very slow for its characteristic of solving an optimization problem. Convolutional neural network can realize fast processing while achieving comparable results. While CS image recovery with high quality not only depends on good reconstruction algorithms, but also good measurements. In this paper, we propose an adaptive measurement network in which measurement is obtained by learning. The new network consists of a fully-connected layer and ReconNet. The fully-connected layer which has low-dimension output acts as measurement. We train the fully-connected layer and ReconNet simultaneously and obtain adaptive measurement. Because the adaptive measurement fits dataset better, in contrast with random Gaussian measurement matrix, under the same measurement rate, it can extract the information of scene more efficiently and get better reconstruction results. Experiments show that the new network outperforms the original one.

With the rapid development and rich applications of mobile Internet, security issues become urgent. For example, piracy of media content image, audio, or video becomes easier because mobile Internet provides more ways to re-distribute media contents. Watermarking has been regarded as a potential solution for identifying pirate copies. However, the watermarking algorithms' security and robustness are still not ideal enough for practical applications, especially in mobile scenarios with more attacks. In this paper, a novel hybrid multiplicative watermarking algorithm is proposed to obtain higher security and good robustness. In this algorithm, two embedding rules are changed according to the secret key, which embed the watermark into Discrete Wavelet Transform DWT coefficients. The secret key improves the watermark system's security. Additionally, the optimum and locally optimum hybrid multiplicative watermarking decoders are proposed, respectively, to detect the watermark. Because it works with two rules, it obtains a tradeoff in robustness. Various comparative experiments are carried out, and results are given to prove the valid of theoretical analysis. Copyright © 2013 John Wiley & Sons, Ltd.

The present work simulates a concept about how to drive droplet flowing through non-wetting (hydrophobic) capillaries without any external force by using many-body dissipative particle dynamics. By decorating the capillary segments with wettability gradients, a droplet with proper radius can be absorbed by the non-wetting capillaries and then constantly flow through the capillary. The simulation results show the droplet can keep flowing through the whole capillaries under certain wettability gradients and the flow velocity also depends on the degree of the wettability gradients. The average wettability of the whole capillary is also essential for the continuous flowing, higher non-wetting capillaries can still keep the flowing with low wettability gradients due to less surface adhesion. A strategy on how to achieve longer flow pathway is also presented. It is also find that unbalanced uptake of droplet via lateral heterogeneous surfaces cannot stir the inside flow of the droplet. The simulation results could inspire the new design of microfluidics in which the transportation of droplet is an important aspect.