Fe/C multilayer thin films were deposited by magnetron sputtering. Small angle X-ray diffraction measurements show very well periodicity of the samples. The modulation period determined from a modified Bragg equation ...Fe/C multilayer thin films were deposited by magnetron sputtering. Small angle X-ray diffraction measurements show very well periodicity of the samples. The modulation period determined from a modified Bragg equation agrees well with that determined from deposition rate. The interfacial roughness parameter ξof several samples calculated by X-ray diffraction is between 3.5(?) and 5.6(?).展开更多
由于Python语言自身的执行效率问题,对高精度编码器电机的解读难以满足需求。经过多方比较,最终采用pigpiod C Interface作为开发基础,实现对电机测速和转向判断的面向对象的封装,并利用swig工具将C++类转换成Python调用,结合了C++的高...由于Python语言自身的执行效率问题,对高精度编码器电机的解读难以满足需求。经过多方比较,最终采用pigpiod C Interface作为开发基础,实现对电机测速和转向判断的面向对象的封装,并利用swig工具将C++类转换成Python调用,结合了C++的高效与Python的便捷。测试结果表明,在树莓派设备上,对于分辨率为11线的霍尔传感器、分辨率为500线的光电传感器,本方案都能够满足精度需求。展开更多
One of the most primary challenges to achieve large-scale hydrogen generation from water electrolysis is the sluggish kinetics and noble metal dependence of cathodic hydrogen evolution reaction(HER).By considering the...One of the most primary challenges to achieve large-scale hydrogen generation from water electrolysis is the sluggish kinetics and noble metal dependence of cathodic hydrogen evolution reaction(HER).By considering the excellent water dissociation catalytic activity of Mo2C, abundant Pt/Mo2C interfaces were facilely engineered via galvanic replacement(gr) by using Mo/Mo2C nanosheets as self-sacrificed templates to alter the alkaline HER mechanism on Pt based catalyst. The rational designed interface-rich gr-Pt/Mo2C catalyst exhibited excellent activity with the overpotential to drive 10 mA/cm2 current density decreased by 18.5 mV compared with the commercial Pt/C catalyst. 34.3 mV/dec Tafel slope confirms the Volmer-Tafel HER route on gr-Pt/Mo2C in alkaline condition. Platinum utilization is calculated to be improved by 9.7 times by considered the low Pt loading in the gr-Pt/Mo2C catalyst. With its satisfied stability, the scalable gr-Pt/Mo2C catalyst shows promising application potential in industrial electrolysis systems.展开更多
Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)limits.However,the ...Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)limits.However,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device performances.In this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK crystals.In addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain boundaries.Meanwhile,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing recombination.As a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our knowledge.This validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells.展开更多
The influence of active elements C and Hf on the interface reactions and wettability between a Ni3Albased superalloy and the ceramic mould material was studied by using a sessile drop experiment, The microstructure of...The influence of active elements C and Hf on the interface reactions and wettability between a Ni3Albased superalloy and the ceramic mould material was studied by using a sessile drop experiment, The microstructure of the alloy interface was investigated by scanning electron microscopy analysis and the phase identification was performed by X-ray diffraction analysis, The results show that interface reactions occur as C and Hf contents reach a critical value, The critical values for C and Hf to cause interface reactions are 0,12 wt% and 1,17 wt%, respectively, The reaction products contain HfO2 and 9Al2OH,Cr2O3, Adsorptions of Hf and interface reactions improve the wettability obviously,展开更多
Engineering application domains need database management systems to supply them with a good means of modeling, a high data access efficiency and a language interface with strong functionality. This paper presents a se...Engineering application domains need database management systems to supply them with a good means of modeling, a high data access efficiency and a language interface with strong functionality. This paper presents a semantic hypergraph model based on relations, in order to express many-to-many relations among objects belonging to defferent semanic classes in engineering applications. A management mechanism expressed by the model and the basic data of engineering databases are managed in main memory. Especially, different objects are linked by different kinds of semantics defined by users, therefore the table swap, the record swap and some unnecessary examinations are reduced and the access efficiency of the engineering data is increased.C language interface that includes some generic and special functionality is proposed for closer connection with application programs.展开更多
First-principle calculations were performed to study the adsorption of boron and its relationship with the morphologies of Ti C.It is found that although the adsorption of boron on all the low-index Ti C crystal plane...First-principle calculations were performed to study the adsorption of boron and its relationship with the morphologies of Ti C.It is found that although the adsorption of boron on all the low-index Ti C crystal planes is thermally favorable,it will be adsorbed more easily by C-terminated {111} and {011} planes,while less possible to be adsorbed by {001}.The study of the formation of B–B clusters indicates that the distribution of boron adatoms on C-terminated(111) and {011} planes will be more uniform,and the diffusion of the adatom further confirms the above results.According to the geometry relationship and growth rate of different crystal planes,it is deduced that the adsorption of boron on Ti C will seriously impede the growth of {111} and {011} planes,which can make Ti C grow into hexagonal platelets.展开更多
文摘Fe/C multilayer thin films were deposited by magnetron sputtering. Small angle X-ray diffraction measurements show very well periodicity of the samples. The modulation period determined from a modified Bragg equation agrees well with that determined from deposition rate. The interfacial roughness parameter ξof several samples calculated by X-ray diffraction is between 3.5(?) and 5.6(?).
文摘由于Python语言自身的执行效率问题,对高精度编码器电机的解读难以满足需求。经过多方比较,最终采用pigpiod C Interface作为开发基础,实现对电机测速和转向判断的面向对象的封装,并利用swig工具将C++类转换成Python调用,结合了C++的高效与Python的便捷。测试结果表明,在树莓派设备上,对于分辨率为11线的霍尔传感器、分辨率为500线的光电传感器,本方案都能够满足精度需求。
基金financial support from the National Natural Science Foundation of China (Nos.21875224 and 21703211)the Natural Science Foundation of Zhejiang Province (No.LGG19B030001)。
文摘One of the most primary challenges to achieve large-scale hydrogen generation from water electrolysis is the sluggish kinetics and noble metal dependence of cathodic hydrogen evolution reaction(HER).By considering the excellent water dissociation catalytic activity of Mo2C, abundant Pt/Mo2C interfaces were facilely engineered via galvanic replacement(gr) by using Mo/Mo2C nanosheets as self-sacrificed templates to alter the alkaline HER mechanism on Pt based catalyst. The rational designed interface-rich gr-Pt/Mo2C catalyst exhibited excellent activity with the overpotential to drive 10 mA/cm2 current density decreased by 18.5 mV compared with the commercial Pt/C catalyst. 34.3 mV/dec Tafel slope confirms the Volmer-Tafel HER route on gr-Pt/Mo2C in alkaline condition. Platinum utilization is calculated to be improved by 9.7 times by considered the low Pt loading in the gr-Pt/Mo2C catalyst. With its satisfied stability, the scalable gr-Pt/Mo2C catalyst shows promising application potential in industrial electrolysis systems.
基金supported by“National Natural Science Foundation of China(U21A20171,U20A20245)”“Hubei Provincial Natural Science Foundation of China(2023AFA010)”+1 种基金“Independent Innovation Projects of the Hubei Longzhong Laboratory(2022ZZ-09)”“Social Public Welfare and Basic Research Special Project of Zhongshan(2020B2015).”。
文摘Two-terminal(2-T)perovskite(PVK)/CuIn(Ga)Se_(2)(CIGS)tandem solar cells(TSCs)have been considered as an ideal tandem cell because of their best bandgap matching regarding to Shockley–Queisser(S–Q)limits.However,the nature of the irregular rough morphology of commercial CIGS prevents people from improving tandem device performances.In this paper,D-homoserine lactone hydrochloride is proven to improve coverage of PVK materials on irregular rough CIGS surfaces and also passivate bulk defects by modulating the growth of PVK crystals.In addition,the minority carriers near the PVK/C60 interface and the incompletely passivated trap states caused interface recombination.A surface reconstruction with 2-thiopheneethylammonium iodide and N,N-dimethylformamide assisted passivates the defect sites located at the surface and grain boundaries.Meanwhile,LiF is used to create this field effect,repelling hole carriers away from the PVK and C60 interface and thus reducing recombination.As a result,a 2-T PVK/CIGS tandem yielded a power conversion efficiency of 24.6%(0.16 cm^(2)),one of the highest results for 2-T PVK/CIGS TSCs to our knowledge.This validation underscores the potential of our methodology in achieving superior performance in PVK/CIGS tandem solar cells.
基金financial support from the National Natural Science Foundation of China (Grant Nos. U1037601 and 51271186)
文摘The influence of active elements C and Hf on the interface reactions and wettability between a Ni3Albased superalloy and the ceramic mould material was studied by using a sessile drop experiment, The microstructure of the alloy interface was investigated by scanning electron microscopy analysis and the phase identification was performed by X-ray diffraction analysis, The results show that interface reactions occur as C and Hf contents reach a critical value, The critical values for C and Hf to cause interface reactions are 0,12 wt% and 1,17 wt%, respectively, The reaction products contain HfO2 and 9Al2OH,Cr2O3, Adsorptions of Hf and interface reactions improve the wettability obviously,
文摘Engineering application domains need database management systems to supply them with a good means of modeling, a high data access efficiency and a language interface with strong functionality. This paper presents a semantic hypergraph model based on relations, in order to express many-to-many relations among objects belonging to defferent semanic classes in engineering applications. A management mechanism expressed by the model and the basic data of engineering databases are managed in main memory. Especially, different objects are linked by different kinds of semantics defined by users, therefore the table swap, the record swap and some unnecessary examinations are reduced and the access efficiency of the engineering data is increased.C language interface that includes some generic and special functionality is proposed for closer connection with application programs.
基金financially supported by the National Natural Science Foundation of China (No.51301068)the Natural Science Foundation of Hebei Province (No.E2014502003 and A2013502120)the Fundamental Research Funds for the Central Universities (No.2014MS116)
文摘First-principle calculations were performed to study the adsorption of boron and its relationship with the morphologies of Ti C.It is found that although the adsorption of boron on all the low-index Ti C crystal planes is thermally favorable,it will be adsorbed more easily by C-terminated {111} and {011} planes,while less possible to be adsorbed by {001}.The study of the formation of B–B clusters indicates that the distribution of boron adatoms on C-terminated(111) and {011} planes will be more uniform,and the diffusion of the adatom further confirms the above results.According to the geometry relationship and growth rate of different crystal planes,it is deduced that the adsorption of boron on Ti C will seriously impede the growth of {111} and {011} planes,which can make Ti C grow into hexagonal platelets.