摘要：Untreated urea-rich wastewater exerts severeadverse impacts on both the environment and human health,prompting extensive attention towards the urea oxidationreaction (UOR) as a sustainable technology to generate cleanenergy in recent years. UOR has a thermodynamic advantageover oxygen evolution reaction (OER) (1.23 V vs reversiblehydrogen electrode, RHE) and only requires 0.37 V (vs RHE),which is considered as an effective alternative to H_(2) production by water electrolysis. However, the inevitable kineticslowness and complex adsorption/desorption during the processhinder its practical application. Most traditional catalystsutilized for the UOR are comprised of precious metals, resulting in limited economic viability. Inspired by natural ureases, Ni-based catalysts have emerged as promisingalternatives owing to their rich deposits, low cost, and theregulated d orbitals of transition metal Ni, demonstratingconsiderable potential for UOR. Currently, numerous studieshave explored Ni-based hydroxides, oxides, chalcogenides, andphosphides in alkaline solutions. In this review, we will explorethe UOR reaction mechanism and summarize the catalystdesign strategies of various Ni-based catalysts recently, especially Ni-MOF, which has been rarely discussed before. Then,the broad prospects of UOR in practical applications aresummarized. Finally, based on the design strategies and performance comparisons discussed above, the challenges andprospects facing the future development of Ni-based electrocatalysts for the UOR will be presented.

摘要：Circulators play a significant role in radar and microwave communication *** paper proposes a broadband and highly efficient plasmonic circulator,which consists of spoof surface plasmon polaritons(SSPPs)waveguides and ferrite disks to support non-reciprocal mode *** simulated performance of symmetrically designed circulator shows that it has an insertion loss of roughly 0.5 dB while the isolation and return loss is more than 12 dB in the frequency range of 6.0 GHz–10.0 GHz(relative bandwidth of 50%).Equivalent circuit model has been proposed to explain the operating mechanism of the plasmonic *** equivalent circuit model,numerical simulations,and experimental results are consistent with each other,which demonstrates the good performance of the proposed plasmonic circulator.

摘要：The tensile properties of 2297-T87 Al–Li alloy thick plates at different thickness position and in different direction were analyzed via tensile testing,optical microscopy(OM),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectrometry(EDS),and transmission electron microscopy(TEM).Results indicated that the ultimate tensile strength(UTS)and yield strength(YS)of the alloy decreased firstly and then increased from the 1/8T position to the 1/2T position,whereas elongation to failure(Ef)decreased gradually such that its value along the rolling direction(RD)was higher than those along the transverse direction(TD)at the same thickness *** the 1/8T position to the 3/8T position of the alloy,the UTS and YS along the TD were higher than those along the *** the 1/2T position of the alloy,the UTS,YS,and Ef along the RD were the highest,whereas those along the normal direction(ND)were the *** observations further revealed that the anisotropy of tensile properties was related to grain morphology,crystal texture,second-phase particles,and Li atom segregation.

摘要：A 40-60 t/h modularized dry coal beneficiation process with a novel method to control the bed was designed around a gas-solid fluidized bed separator. Furthermore, the hydrodynamics of medium-solids consisting of wide-size-range magnetite powder （0.3-0.06 ram） and 〈1 mm fine coal were numerically studied. The simulation results show that the fluidization performance of the wide-size-range medium-solid bed is good. The separation performance of the modularized system was then investigated in detail using a mixture of 〈0.3 mm magnetite powder （mass fraction of 0.3-0.06 mm particles is 91.38 %） and 〈1 mm fine coal as solid media. The experimental results show that at separation densities of 1.33 g/cm^3 or 1.61 g/cm^3, 50-6 mm coal can be separated effectively with probable error, E, values of 0.05 g/cm^3 and 0.06 g/cm^3, respectively. This technique is beneficial for saving water resources and for the clean utilization of coal.

摘要：AIM: To explore the effect of SDF-1α on the development of experimental corneal neovascularization (CRNV).METHODS: CRNV was induced by alkali injury in mice. The expression of SDF-1α and CXCR4 in burned corneas was examined by Flow Cytometry. Neutralizing anti-mouse SDF-1α antibody was locally administrated after alkali injury and the formation of CRNV 2 weeks after injury was assessed by Immunohistochemistry. The expression of VEGF and C-Kit in burned corneas was detected by ***: The number of CRNV peaks at 2 weeks after alkali injury. Compared to control group, SDF-1α neutralizing antibody treatment significantly decreased the number of CRNV. RT-PCR confirmed that SDF-1α neutralizing antibody treatment resulted in decreased intracorneal VEGF and C-Kit ***: SDF-1α neutralizing antibody treated mice exhibited impaired experimental CRNV through down regulated VEGF and C-Kit expression.

摘要：Based on the study of existing typical micro-milling tools and the actual demand for micro-milling tools, the P3 design principle and design flow for ultra-hard micro-milling tool were introduced to give basic guidance for the optimization of micro-milling tools. Then, according to the P3 design flow, the manufacturing process of polycrystalline diamond(PCD) micro-milling tool was proposed, and the PCD micro-milling tool with diameter of 0.5 mm was developed. Finally, the micro-milling test on the slot was carried out to study the milling performance of PCD micromilling tool.

摘要：The acceleration autopilot design for skid-to-turn （STT） missile faces a great challenge owing to coupling effect among planes, variation of missile velocity and its parameters, inexistence of a complete state vector, and nonlinear aerodynamics. Moreover, the autopilot should be designed for the entire flight envelope where fast variations exist. In this paper, a design of integrated roll-pitch-yaw autopilot based on global fast terminal sliding mode control （GFTSMC） with a partial state nonlinear observer （PSNLO） for STT nonlinear time-varying missile model, is employed to address these issues. GFTSMC with a novel sliding surface is proposed to nullify the integral error and the singularity problem without application of the sign function. The proposed autopilot consisting of two-loop structure, controls STT maneuver and stabilizes the rolling with a PSNLO in order to estimate the immeasurable states as an output while its inputs are missile measurable states and control signals. The missile model considers the velocity variation, gravity effect and parameters＇ variation. Furthermore, the environmental conditions＇ dynamics are mod- eled. PSNLO stability and the closed loop system stability are studied. Finally, numerical simulation is established to evaluate the proposed autopilot performance and to compare it with existing approaches in the literature.

摘要：The feature extraction algorithm plays an important role in face recognition. However, the extracted features also have overlapping discriminant information. A property of the statistical uncorrelated criterion is that it eliminates the redundancy among the extracted discriminant features, while many algorithms generally ignore this property. In this paper, we introduce a novel feature extraction method called local uncorrelated local discriminant embedding(LULDE). The proposed approach can be seen as an extension of a local discriminant embedding(LDE)framework in three ways. First, a new local statistical uncorrelated criterion is proposed, which effectively captures the local information of interclass and intraclass. Second, we reconstruct the affinity matrices of an intrinsic graph and a penalty graph, which are mentioned in LDE to enhance the discriminant property. Finally, it overcomes the small-sample-size problem without using principal component analysis to preprocess the original data, which avoids losing some discriminant information. Experimental results on Yale, ORL, Extended Yale B, and FERET databases demonstrate that LULDE outperforms LDE and other representative uncorrelated feature extraction methods.

摘要：In this paper,by combining a second-order sliding mode(SOSM)algorithm with the saturation technique,a novel SOSM control scheme has been *** feature of the proposed SOSM controller lies that there is a saturation function imposed on the sliding variable,which could significantly enlarge the domain of attraction for the closed-loop *** geometric method has been utilized to prove that all the sliding variables will be steered to the origin in a finite ***,the relation between the control parameters and the shape of the phase trajectory has also been ***,the proposed method has been applied to the tracking control problem for a robotic manipulator.

摘要：The relationship among the surface fissure ratio, moisture content, seepage coefficient and deformation modulus of field unsaturated expansive soil in Nanning, Guangxi province, china, was obtained by a direct or indirect method. Digital images of expansive soil of the surface fissure with different moisture contents were analyzed with the binarization statistic method. In addition, the fissure fractal dimension was computed with a self-compiled program. Combined with in situ seepage and loading plate tests, the relationship among the surface fissure ratio, moisture content, seepage coefficient and deformation modulus was initially established. The surface fissure ratio and moisture content show a linear relation, ＂y=-0.019 1x＋1.028 5＂ for rufous expansive soil and ＂y=-0.07 1x＋2.610 5＂ for grey expansive soil. Soil initial seepage coefficient and surface fissure ratio show a power function relation, ＂y=1× 10^-9exp（15.472x）＂ for rufous expansive soil and ＂y=5× 10^-7exp（4.209 6x）＂ for grey expansive soil. Grey expansive soil deformation modulus and surface fissure ratio show a power fimction relation of ＂y=3.935 7exp（0.993 6x）＂. Based on the binarization and fractal dimension methods, the results show that the surface fissure statistics can depict the fissure distribution in the view of two dimensions. And the evolvement behaviors of permeability and the deformation modulus can indirectly describe the developing state of the fissure. The analysis reflects that the engineering behaviors of unsaturated expansive soil are objectively influenced by fissure.