摘要：Experimental investigations are performed in a three-stage low-speed axial compressor with variable inlet guide vanes(IGV) and adjustable *** characteristics of the compressor,especially the efficiency and stall margin,are analyzed in design and off-design operation conditions by adjusting stagger angles of IGV and stators as well as changing the rotational *** experimental results show that the off-design performance of the multistage axial compressor is improved by restaggering of IGV and stators related to rotational *** the background of engineering applications,digital signal processing(DSP) technique is used to realize online adjustment of stagger angles according to the corresponding relations between incidence angles of rotor and rotational speed.

摘要：The expansion of new structures in aggregation-induced emission/aggregation-induced emission enhancement(AIE/AIEE)systems has attracted persistent attention recently,from which more luminescent functional molecules with characteristic skeletons are derived to satisfy specialized *** this study,a series of derivatives cored by tetraphenyl enamine with various terminal groups were designed and synthesized based on a novel p-πconjugate chain structure(–C=C–N–).Experimental and theoretical studies reveal that attaching modified groups to enamine core is decisive to achieve successful conversion from non-luminance to ***,due to different substituent effect on electronic structure,molecular conformation and molecular packing,diverse enamine compounds exhibited prominent substituent tunable emission properties,realizing regulated AIEE effect and multicolor *** results not only offer a new method to design AIEgens/AIEEgens with p-πconjugate chain structures,but also provide in-depth knowledge for functional modifications of more novel AIE/AIEE units and materials.

摘要：Space deployable structures with large calibers, high accuracy, and large folding ratios are indispensable equipment in the aerospace field. Given that the single-DOF 3 RR-3 RRR deployable unit cannot be fully folded, this study proposes a 3 UU-3 URU deployable unit with two kinds of DOF: folding movement and orientation adjustment. First, based on the G-K formula, the DOF of the 3 UU-3 URU unit is analyzed. Then, the 3 UU-3 URU unit is used to construct a deployable truss antenna with a curved surface, and the DOF of the whole deployable antenna containing multiple 3 UU-3 URU units is calculated. The structural design of a deployable antenna with two loops is carried out with specific parameters and geometric relations. Next, a DOF simulation of a basic combination unit composed of three 3 UU-3 URU units is performed. Finally, a prototype of the basic combination unit is manufactured, and the DOF of the mechanism is experimentally verified.

摘要：The creep anisotropy behavior under different stresses at 180℃ of hot-extruded AZ91−2Y magnesium alloy with pre-compression(PC)and without pre-compression(NPC)was ***,texture and mechanical properties of the alloy were examined by scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),transmission electron microscopy(TEM)and tensile creep *** results revealed that the creep resistance was proportional to the volume fraction of spherical Mg_(17)Al_(12) *** dynamic precipitation of large volume fraction of lamellar Mg_(17)Al_(12) in NPC samples leads to the basaláañslip as the dominant creep mechanism,and the NPC samples have obvious *** the PC samples,dynamic precipitation of large volume fraction of spherical Mg_(17)Al_(12) has inhibitory effect on the basaláañ*** pyramidalác+añslip and twinning improve the creep anisotropy resistance significantly.

摘要：Short-range ordering(SRO)is one of the most important structural features of high entropy alloys(HEAs).However,the chemical and structural analyses of SROs are very difficult due to their small size,complexed compositions,and varied *** electron microscopy(TEM)as well as its aberration correction techniques are powerful for characterizing SROs in these compositionally complex *** this short communication,we summarized recent progresses regarding characterization of SROs using TEM in the field of *** using advanced TEM techniques,not only the existence of SROs was confirmed,but also the effect of SROs on the deformation mechanism was ***,the perspective related to application of TEM techniques in HEAs are also discussed.

摘要：Although dielectric elastomer(DE)with substantial actuated strain(AS)has been reported 20 years ago,its scientific understanding remains *** most accepted theory of DE,which is proposed in 2000,holds the view that AS of DE is induced by the Maxwell *** to this theory,materials have similar ratios of permittivity and Young’s modulus should have similar AS,while the experimental results are on contrary to this theory,and the experimental AS has no relationship with ideal ***,a new dipole-conformation-actuated strain cross-scale model is proposed,which can be generally applied to explain the AS of DE without *** to this model,several characteristics of an ideal DE are listed in this work and a new DE based on polyphosphazene(PPZ)is *** AS of PPZ can reach 84%without any *** last,a PPZ-based all soft artificial heart(ASAH)is built,which works in the similar way with natural myocardium,indicating that this material has great application potential and possibility in the construction of an ASAH for heart failure(HF)patients.

摘要：It is a great challenge to develop highly active oxygen evolution reaction(OER)electrocatalysts with superior *** this study,a NiFe layered double hydroxidedecorated phosphide(NiFe LDH@CoP/NiP_(3))was constructed to display satisfactory OER activity and good stability for water splitting in alkaline *** an overpotential of 300 mV,NiFe LDH@CoP/NiP_(3) achieved a current density of 82 mA cm^(-2) for the OER,which was 9.1 and 2.3 times that of CoP/NiP_(3) and NiFe LDH,***,the reconstruction behavior,during which oxyhydroxides formed,was studied by a combination of X-ray photoelectron spectroscopy,Raman spectroscopy,and scanning electron microscopy.A synergistic effect between NiFe LDH and CoP/NiP_(3) was also observed for the hydrogen evolution ***,when NiFe LDH@CoP/NiP_(3) acted as both the cathode and anode for overall water splitting,a high current density of 100 mA cm^(-2) was maintained for more than 275 *** addition,under Xe light irradiation,a solar-to-hydrogen efficiency of 9.89% was achieved for solar-driven water *** work presents the coupling of different active compositions,and can provide a reference for designing bifunctional electrocatalysts.

摘要：Silicon(Si)is a promising anode material for next-generation Li-ion *** nanometer-sized Si could alleviate the pulverization caused by large volume changes during deep ***,compression between agglomerated Si particles causes Si cracking and electrode *** this,we engineered a mechanical cushioning space between Si particles via elastic hollow graphene shells(GSs)to flexibly buffer volume changes and maintain the stability of the electrode *** stress generated from the Si volume expansion during lithiation was mechanically buffered and gently released by compression of the hollow space of the *** this Si/GS composite electrode,GS also reduced the local agglomeration of Si particles and effectively improved the overall *** these advantages,the designed Si/GS electrode showed an enhanced cycling performance with more than 1200 mA h g^(-1) at 0.8 A g^(-1) and an excellent rate capability of 1025 mA h g^(-1) at 4 A g^(-1) after 200 cycles.