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The performance of adhesive bonded subassemblies and vehicle structures strongly depends on not only the properties of the adherends and adhesives but also the gap between the workpieces. An excessive gap between the joined structural elements could result in the joint strength decreased. In this study, a single-sided piercing riveting (SSPR) of workpieces was proposed and analyzed to ensure the part fit-up. The SSPR process has been modeled using the explicit finite element code LS-DYNA. A 3D model including the workpieces, rivet and riveting tools was generated. The model simulates the rivet piercing and deformation of 2 mm thick aluminum alloy AA5052. It was found that rivet speed and rivet leg chamfers are the main factors to influence the gap between the workpieces and consequently the quality of the riveted joints. To minimize the gap between the workpieces and optimizing the joint strength, proper riveting velocity and rivet leg chamfer are recommended. [DOI: 10.1115/1.4001249] Keywords: single-sided piercing riveting (SSPR), SSPR-bonding, finite element modeling, aluminum alloy, joint quality

Four kinds of Zn1−xSnxO (X = 0%, 1%, 3%, 5%) nanowires with different concentrations are synthesized by a hydrothermal method. The samples are characterized and measured by X‐ray diffraction (XRD), scanning electron microscopy (SEM), and X‐Ray photoelectron spectroscopy (XPS). Then, the nanostructures are arranged on predesigned Ti/Au electrodes through the dielectrophoresis (DEP) nanomanipulation technique to fabricate four humidity sensors and investigate the humidity sensing properties. The results demonstrate that the Sn doping process can regulate the surface oxygen vacancy concentration and improve the performance of humidity sensors. In particular, the 3% Sn‐doped ZnO humidity sensor exhibits higher sensitivity with a response/recovery time of 4s/2s, lower hysteresis, and better repeatability. In addition, the sensing mechanisms are discussed in depth by combining complex impedance spectroscopy and multilayer adsorption theory. The obtained results indicate that a certain amount of Sn doping can introduce oxygen vacancies, adjust the lattice and surface state, and hence modulate the sensing properties of ZnO nanosensors. [ABSTRACT FROM AUTHOR]

To effectively address the challenges of large motions, complex backgrounds and large occlusions in videos, we introduce an end-to-end method for video frame interpolation based on recurrent residual convolution and depthwise over-parameterized convolution in this paper. Specifically, we devise a U-Net architecture utilizing recurrent residual convolution to enhance the quality of interpolated frame. First, the recurrent residual U-Net feature extractor is employed to extract features from input frames, yielding the kernel for each pixel. Subsequently, an adaptive collaboration of flows is utilized to warp the input frames, which are then fed into the frame synthesis network to generate initial interpolated frames. Finally, the proposed network incorporates depthwise over-parameterized convolution to further enhance the quality of interpolated frame. Experimental results on various datasets demonstrate the superiority of our method over state-of-the-art techniques in both objective and subjective evaluations. [ABSTRACT FROM AUTHOR]

Mn doped ZnO nano-particles were synthesized by a solution route and annealed in N2, O2, and Ar, respectively. X-ray diffraction and X-ray photoelectron spectroscopy measurements show that the samples possess typical wurtzite structure and have no other impurity phases. Magnetization loops for ZnO samples were measured and clearly show typical ferromagnetic saturation behavior. With the combination of defect analysis based on photoluminescence spectroscopy and first-principle calculations of the possible magnetic defect centers in Mn doped ZnO, the effect of defects on the nature and origin of ferromagnetism was investigated. The results suggest oxygen vacancies, especially singly ionized oxygen vacancies, play a crucial role in mediating ferromagnetism in the Mn doped ZnO system. [ABSTRACT FROM AUTHOR]

The core-shell structure of the CoP@Ni(OH) 2 ·0.75H 2 O nanosheet arrays with CoP as the skeleton exhibits excellent electrochemical performance. The research on the structure tuning of CoP in supercapacitors has received extensive attention. However, low specific capacitance and energy density limit its further development. Here, we successfully synthesize the CoP@Ni(OH) 2 ·0.75H 2 O core-shell nanosheets structure on carbon cloth. CoP nanowires, as the core, can provide efficient charge transportation path for electron transfer, while the thin Ni(OH) 2 ·0.75H 2 O nanosheets shell can increase the specific surface area and curtail the transport distance. As a result, the as-prepared CoP@Ni(OH) 2 ·0.75H 2 O nanosheet arrays electrode presents an outstanding specific capacity of 168.61 mAh g−1 at 1 A g−1. The assembled asymmetric supercapacitor (ASC) of CoP@Ni(OH) 2 ·0.75H 2 O//activated carbon displays the highest energy density of 33.78 W h kg−1 at 800 W kg−1, as well as the remarkable cycling stability (capacitance retention of 98.5% after 10,000 cycles). Furthermore, ten parallel LEDs can be powered up by two ASCs connected in series. Thus, this article provides a new idea for the core-shell structure prepared by using CoP as the skeleton. [ABSTRACT FROM AUTHOR]

Three sizes of CuO nanosheets were synthesized by hydrothermal method. The structure and morphology of CuO nanosheets were characterized by X-ray diffraction and scanning electron microscopy. Dielectrophoresis nano-manipulation technique was employed to arrange the materials on pre-designed Ti/Au electrodes to fabricate the three humidity sensors, and the sensing properties were then tested. The experimental results show that the sensitivity greatly increases with the decreasing size of CuO nanosheets, the sensitivity of sensor a, b, c are 369%, 3278%, 22,611% in 97.3% RH, respectively. The smaller sized CuO nanomaterials have better response characteristic, the response time of sensor a, b, c under 11.3–97.3% RH are 53 s, 49 s, 32 s, respectively. And correspondingly, hysteresis properties and the repeatability are also a little influenced. In addition, based on complex impedance spectroscopy and multilayer adsorption theory, the impact of size on humidity sensing property was discussed. The results indicated the feasibility to obtain higher performance of humidity sensor, especially the higher sensitivity, via employment the smaller size sensing nanomaterials. [ABSTRACT FROM AUTHOR]

In wireless sensor networks, the unbalanced load of nodes is easy to cause low energy nodes die prematurely. It may lead network collapse. According to the problem of unbalanced load and short network lifetime, we research the relationship between neighbour-residual energy, transmission power and load. Considering the centralized algorithm causes larger information easily, we introduce the distributed thought. Then a load balancing evaluation model is constructed. It is reasonable and effective, which is proved by Lyapunov stability theorem and Lagrange multiplier method. After that, a distributed topology control algorithm based on load balancing evaluation model (LBEM) is proposed. The simulation results show that LBEM can balance network load and energy consumption to enhance network lifetime. [ABSTRACT FROM AUTHOR]

Undoped ZnO nano-particles were synthesized by a solution route and annealed in N2, O2, and Ar, respectively. X-ray diffraction and X-ray photoelectron spectroscopy measurements show that the samples possess typical wurtzite structure and have no other impurity phases. Magnetization loops for the ZnO samples were measured and clearly show typical ferromagnetic saturation behavior. With the combination of defect analysis based on photoluminescence spectroscopy and first-principles calculations of the possible magnetic defect centers in ZnO, the effect of defects on the nature and origin of ferromagnetism was investigated. The results suggest oxygen defects, especially singly ionized oxygen vacancies, play a crucial role in mediating ferromagnetism in the undoped ZnO system. [ABSTRACT FROM AUTHOR]

Integrated partial denitrification-anammox (PD/A) process was considered as a novel strategy for low ammonia wastewater treatment, but the potential roles of the functional bacteria were still unclear. In this study, metagenomic binning analysis coupling with metatranscriptomic analysis was used to reveal the metabolic patterns in a stable operating PD/A system driven by glycerol. The cross-feeding between Bacillus and Candidatus Brocadia , the two dominant functional bacteria that contributed 81.1 % of the total gene expression, was constructed. Bacillus exhibited high nitrite production potential in the assimilatory nitrate reduction pathway instead of partial denitrification. And Bacillus was the main glycerol utilizer capable of synthesizing intracellular glycogen and polyhydroxybutyrate, which was also the potential branched-chain amino acids and B-vitamins supplier. Candidatus Brocadia as an anammox bacteria surprisingly expressed the activity of 3-phosphate glycerol (obtained from Bacillus) degradation. This study provided a new understanding of the metabolic patterns and interactions in PD/A system. [Display omitted] • 24 high-quality MAGs with completeness > 90 % and contamination < 5 % were obtained. • Bacillus and Ca. Brocadia dominated PD/A and contributed 81.1 % of gene expression. • Bacillus tended to produce nitrite for AnAOB via ANR rather than denitrification. • Ca. Brocadia got carbon source from glycerol degradation rather than CO 2 fixation. • Bacillus was the main BCAAs and B-vitamins supplier in the PD/A system. [ABSTRACT FROM AUTHOR]