In this study,ZnO/In_(2)O_(3)-heterostructured nanosheets were prepared using a one-step hydrothermal method.The effects of ZnO content on the gas-sensing performance were discussed,with ZnO/In_(2)O_(3)-2 exhibiting t...In this study,ZnO/In_(2)O_(3)-heterostructured nanosheets were prepared using a one-step hydrothermal method.The effects of ZnO content on the gas-sensing performance were discussed,with ZnO/In_(2)O_(3)-2 exhibiting the highest performance among the prepared sensors.The response of ZnO/In_(2)O_(3)-2 to n-butanol was 302 at 26℃,which was 11.93 times higher than that of pure In_(2)O_(3).Among the eight tested gases,ZnO/In_(2)O_(3)-2 displayed the highest response to n-butanol.Moreover,the lower detection limit of the ZnO/In_(2)O_(3)nanosheets was reduced from 10×10^(-6)to 0.1×10^(-6)(for pure In_(2)O_(3)nanosheets)toward n-butanol.This is because the doping of Zn2+increases the number of oxygen vacancies on the sensor surface and allows the formation of an n-n heterostructure between ZnO and In_(2)O_(3),which increases the initial resistance of the sensor.展开更多
A different approach,using the molecular beam epitaxy (MBE)-grown ZnS-based Schottky photodiode technology,is applied to fabricate an 8×8 photodiode array.The micro-processing procedures of this photodiode array ...A different approach,using the molecular beam epitaxy (MBE)-grown ZnS-based Schottky photodiode technology,is applied to fabricate an 8×8 photodiode array.The micro-processing procedures of this photodiode array including standard photolithography,a number of metallisation,wet-chemical etching and SiO_2 deposition for insulation are developed.The detector is characterized to have a cutoff wavelength at 340 nm and the photo-responsivity measurements on the pixels result an ultraviolet (UV) response as high as 0.15 A/W,corresponding to an external quantum efficiency of 55% in the visible-blind spectral ranging from 400 down to 250nm.Imaging tests indicate that this array is able to capture the intensity profile of a given UV light source with reasonably good capability.展开更多
This paper presents an investigation on the effect of probe support on the flow field of an axial compressor.The experiment is carried out in a large-scale low-speed research compressor.A cylindrical probe support int...This paper presents an investigation on the effect of probe support on the flow field of an axial compressor.The experiment is carried out in a large-scale low-speed research compressor.A cylindrical probe support intruding to 50% blade span was installed at 50% chord upstream from the rotor leading edge.The region from 5° to 32° off the probe support in the direction of rotation at the rotor outlet was measured with a 5-hole probe and a high-response total pressure probe.The experiment is performed at both near-design and near-stall points.The measuring results of 5-hole probe and high-response total pressure probe indicate that the probe blockage effect is different at different blade spans.The wake of the probe support weakens the leakage vortex intensity at the tip region,leading to greater total pressure rise.At near-design condition,the presence of probe support has a negative effect on the region from 75% to 92% span,while improves the flow field below 75% span.At near stall condition,the probe support has a negative effect on the region from 70% to 90% span,and almost has no influence on the flow field below 70% span.展开更多
基金financially supported by the National R&D Program of China(No.2020YFB2008702)the National Natural Science Foundation of China(Nos.62033002,61833006,62071112 and 61973058)+4 种基金the 111 Project(No.B16009)the Fundamental Research Funds for the Central Universities in China(Nos.N180408018,N2004019 and N2004028)Liaoning Revitalization Talents Program(No.XLYC1807198)Liaoning Province Natural Science Foundation(No.2020-KF-11-04)Hebei Natural Science Foundation(No.F2020501040)。
文摘In this study,ZnO/In_(2)O_(3)-heterostructured nanosheets were prepared using a one-step hydrothermal method.The effects of ZnO content on the gas-sensing performance were discussed,with ZnO/In_(2)O_(3)-2 exhibiting the highest performance among the prepared sensors.The response of ZnO/In_(2)O_(3)-2 to n-butanol was 302 at 26℃,which was 11.93 times higher than that of pure In_(2)O_(3).Among the eight tested gases,ZnO/In_(2)O_(3)-2 displayed the highest response to n-butanol.Moreover,the lower detection limit of the ZnO/In_(2)O_(3)nanosheets was reduced from 10×10^(-6)to 0.1×10^(-6)(for pure In_(2)O_(3)nanosheets)toward n-butanol.This is because the doping of Zn2+increases the number of oxygen vacancies on the sensor surface and allows the formation of an n-n heterostructure between ZnO and In_(2)O_(3),which increases the initial resistance of the sensor.
文摘A different approach,using the molecular beam epitaxy (MBE)-grown ZnS-based Schottky photodiode technology,is applied to fabricate an 8×8 photodiode array.The micro-processing procedures of this photodiode array including standard photolithography,a number of metallisation,wet-chemical etching and SiO_2 deposition for insulation are developed.The detector is characterized to have a cutoff wavelength at 340 nm and the photo-responsivity measurements on the pixels result an ultraviolet (UV) response as high as 0.15 A/W,corresponding to an external quantum efficiency of 55% in the visible-blind spectral ranging from 400 down to 250nm.Imaging tests indicate that this array is able to capture the intensity profile of a given UV light source with reasonably good capability.
基金funded by the National Natural Science Foundation of China,Grant No.51161130525,51136003,and the 111 Project,No.B07009
文摘This paper presents an investigation on the effect of probe support on the flow field of an axial compressor.The experiment is carried out in a large-scale low-speed research compressor.A cylindrical probe support intruding to 50% blade span was installed at 50% chord upstream from the rotor leading edge.The region from 5° to 32° off the probe support in the direction of rotation at the rotor outlet was measured with a 5-hole probe and a high-response total pressure probe.The experiment is performed at both near-design and near-stall points.The measuring results of 5-hole probe and high-response total pressure probe indicate that the probe blockage effect is different at different blade spans.The wake of the probe support weakens the leakage vortex intensity at the tip region,leading to greater total pressure rise.At near-design condition,the presence of probe support has a negative effect on the region from 75% to 92% span,while improves the flow field below 75% span.At near stall condition,the probe support has a negative effect on the region from 70% to 90% span,and almost has no influence on the flow field below 70% span.
