Moist-electric generation,a green and environmentally friendly energy harvesting technology,is undoubt-edly one of the effective methods to alleviate energy shortages and environmental damage.However,the lack of fiber...Moist-electric generation,a green and environmentally friendly energy harvesting technology,is undoubt-edly one of the effective methods to alleviate energy shortages and environmental damage.However,the lack of fiber-like moist-electric generators(MEGs)that combine continuous power generation and high electrical output performance has constrained the development of moist-electric in the fields of flexi-ble wearable and self-power supplies.In this work,sodium alginate(SA)/multi-walled carbon nanotubes(MWCNT)fibers with axial heterogeneous(axi-he)of oxygen-containing functional groups(Ocfgs)are prepared through a mold forming method in assistance with the coagulation process.The interaction be-tween axi-he MEG and moisture is investigated by analyzing the electrical signal changes of dried MEG under moisture stimulation.The maximum output voltage and current of axi-he MEG can reach 0.35 V and 1.92μA under the stimulation of moisture.Based on the regulation of Ocfgs,axi-he MEG has a con-tinuous high moist-electric performance and environmental adaptability.The maximum output power density(Pmo)of axi-he MEG with a length of only 2 cm can reach 27.37μW cm-2 at RH=90%,which exceeds most of the MEGs reported in literature.Meanwhile,a continuous output voltage of 0.33-0.37 V for more than 15 h can be obtained from this axi-he MEG.Thus,the axi-he MEG from Ocfg distribution design and mold forming method provides a new way of clean energy generation using moisture from the ambient environment,exhibiting enormous potential in energy supply for Internet of Things(IoT)devices.展开更多
A solution-treated AZ91 bulk material was deep-surface-rolled at room temperature to investigate the effect of deep surface rolling on the microstructure and mechanical properties of the alloy. Microhardness and micro...A solution-treated AZ91 bulk material was deep-surface-rolled at room temperature to investigate the effect of deep surface rolling on the microstructure and mechanical properties of the alloy. Microhardness and microstructure along the depth of the treated surface layer were characterized. The results show that the affected layer was up to 2.0 mm thick and consisted of three sublayers: a severe deformation layer with thickness of about 400 μm from the topmost surface, a medium deformation layer with thickness of around 600 μm and a small deformation layer up to 1000 μm thick. In addition to grain refinement in the deformation layer, strain-induced precipitation of β phase (Mg17Al12) was observed, particularly in the severe and medium deformation layers. It is believed that the cooperative effects of grain refinement, strain hardening and precipitation strengthening led to the significant increase in hardness of the AZ91 alloy after the deep surface rolling.展开更多
基金supported by the National Natural Science Foundation of China(No.22073015)the National Key R&D Program of China(No.2022YFB3704600).
文摘Moist-electric generation,a green and environmentally friendly energy harvesting technology,is undoubt-edly one of the effective methods to alleviate energy shortages and environmental damage.However,the lack of fiber-like moist-electric generators(MEGs)that combine continuous power generation and high electrical output performance has constrained the development of moist-electric in the fields of flexi-ble wearable and self-power supplies.In this work,sodium alginate(SA)/multi-walled carbon nanotubes(MWCNT)fibers with axial heterogeneous(axi-he)of oxygen-containing functional groups(Ocfgs)are prepared through a mold forming method in assistance with the coagulation process.The interaction be-tween axi-he MEG and moisture is investigated by analyzing the electrical signal changes of dried MEG under moisture stimulation.The maximum output voltage and current of axi-he MEG can reach 0.35 V and 1.92μA under the stimulation of moisture.Based on the regulation of Ocfgs,axi-he MEG has a con-tinuous high moist-electric performance and environmental adaptability.The maximum output power density(Pmo)of axi-he MEG with a length of only 2 cm can reach 27.37μW cm-2 at RH=90%,which exceeds most of the MEGs reported in literature.Meanwhile,a continuous output voltage of 0.33-0.37 V for more than 15 h can be obtained from this axi-he MEG.Thus,the axi-he MEG from Ocfg distribution design and mold forming method provides a new way of clean energy generation using moisture from the ambient environment,exhibiting enormous potential in energy supply for Internet of Things(IoT)devices.
基金Project(2016ZE53046)supported by the Aviation Science Foundation of ChinaProject(201606295009)supported by the China Scholarship CouncilProject supported by Top International University Visiting Program for Outstanding Young Scholars of Northwestern Polytechnical University,China
文摘A solution-treated AZ91 bulk material was deep-surface-rolled at room temperature to investigate the effect of deep surface rolling on the microstructure and mechanical properties of the alloy. Microhardness and microstructure along the depth of the treated surface layer were characterized. The results show that the affected layer was up to 2.0 mm thick and consisted of three sublayers: a severe deformation layer with thickness of about 400 μm from the topmost surface, a medium deformation layer with thickness of around 600 μm and a small deformation layer up to 1000 μm thick. In addition to grain refinement in the deformation layer, strain-induced precipitation of β phase (Mg17Al12) was observed, particularly in the severe and medium deformation layers. It is believed that the cooperative effects of grain refinement, strain hardening and precipitation strengthening led to the significant increase in hardness of the AZ91 alloy after the deep surface rolling.
