In order to investigate the regularity of metal magnetic signals of ferromagnetic materials under the effect of applied load, the static tensile test of Q235 steel and 18CrNiWA steel plate specimens were conducted and...In order to investigate the regularity of metal magnetic signals of ferromagnetic materials under the effect of applied load, the static tensile test of Q235 steel and 18CrNiWA steel plate specimens were conducted and metal magnetic memory signals of specimens were measured during the test process. The influencing factors of metal magnetic memory signals and the relationship between axial applied load and signals were analyzed. The fracture and microstructure of the specimens were observed. The results show that the magnetic signals corresponding to the measured points change linearly approximately with increasing axial load. The microstructure of Q235 steel is ferrite and perlite, whereas that of 18CrNiWA steel is bainite and low-carbon martensite. The fracture of these two kinds of specimens is ductile rupture; carbon content of specimen materials and dislocation glide give much contribution to the characteristics of magnetic curves.展开更多
The first binuclear iron fullerene derivative of(η 2 C 60 )[Fe(CO) 2(C 5H 5)] 2 , which was yellow brown and sensitive to air and moisture, was prepared by the reaction of trans [Fe(CO) 2(C 5H 5)] 2 with C 60 in benz...The first binuclear iron fullerene derivative of(η 2 C 60 )[Fe(CO) 2(C 5H 5)] 2 , which was yellow brown and sensitive to air and moisture, was prepared by the reaction of trans [Fe(CO) 2(C 5H 5)] 2 with C 60 in benzene under an atmosphere of dried nitrogen using conventional Schlenk techniques and has been characterized by using elementary analysis and IR, 1H NMR, 13 C NMR and XPS spectra. The infrared spectrum of the title compound indicates the disappearance of ν CO at 1 760 cm -1 for bridge carbonyl and the appearance of the only terminal CO lying at a higher wave number than that of the starting material, which reveals the electron deficient behavior of C 60 . And the important 1H, 13 C NMR chemical shift and XPS of trans [Fe(CO) 2(C 5H 5)] 2 , C 60 and its novel complex along with their relative assignments are briefly discussed.展开更多
The hydrogen evolution reaction(HER)is a promising way to produce hydrogen,and the use of non-precious metals with an excellent electrochemical performance is vital for this.Carbon-based transition metal catalysts hav...The hydrogen evolution reaction(HER)is a promising way to produce hydrogen,and the use of non-precious metals with an excellent electrochemical performance is vital for this.Carbon-based transition metal catalysts have high activity and stability,which are important in reducing the cost of hydrogen production and promoting the development of the hydrogen production industry.However,there is a lack of discussion regarding the effect of carbon components on the performance of these electrocatalysts.This review of the literature discusses the choice of the carbon components in these catalysts and their impact on catalytic performance,including electronic structure control by heteroatom doping,morphology adjustment,and the influence of self-supporting materials.It not only analyzes the progress in HER,but also provides guidance for synthesizing high-performance carbon-based transition metal catalysts.展开更多
基金Projects(50235030, 50505052) supported by the National Natural Science Foundation of China
文摘In order to investigate the regularity of metal magnetic signals of ferromagnetic materials under the effect of applied load, the static tensile test of Q235 steel and 18CrNiWA steel plate specimens were conducted and metal magnetic memory signals of specimens were measured during the test process. The influencing factors of metal magnetic memory signals and the relationship between axial applied load and signals were analyzed. The fracture and microstructure of the specimens were observed. The results show that the magnetic signals corresponding to the measured points change linearly approximately with increasing axial load. The microstructure of Q235 steel is ferrite and perlite, whereas that of 18CrNiWA steel is bainite and low-carbon martensite. The fracture of these two kinds of specimens is ductile rupture; carbon content of specimen materials and dislocation glide give much contribution to the characteristics of magnetic curves.
文摘The first binuclear iron fullerene derivative of(η 2 C 60 )[Fe(CO) 2(C 5H 5)] 2 , which was yellow brown and sensitive to air and moisture, was prepared by the reaction of trans [Fe(CO) 2(C 5H 5)] 2 with C 60 in benzene under an atmosphere of dried nitrogen using conventional Schlenk techniques and has been characterized by using elementary analysis and IR, 1H NMR, 13 C NMR and XPS spectra. The infrared spectrum of the title compound indicates the disappearance of ν CO at 1 760 cm -1 for bridge carbonyl and the appearance of the only terminal CO lying at a higher wave number than that of the starting material, which reveals the electron deficient behavior of C 60 . And the important 1H, 13 C NMR chemical shift and XPS of trans [Fe(CO) 2(C 5H 5)] 2 , C 60 and its novel complex along with their relative assignments are briefly discussed.
文摘The hydrogen evolution reaction(HER)is a promising way to produce hydrogen,and the use of non-precious metals with an excellent electrochemical performance is vital for this.Carbon-based transition metal catalysts have high activity and stability,which are important in reducing the cost of hydrogen production and promoting the development of the hydrogen production industry.However,there is a lack of discussion regarding the effect of carbon components on the performance of these electrocatalysts.This review of the literature discusses the choice of the carbon components in these catalysts and their impact on catalytic performance,including electronic structure control by heteroatom doping,morphology adjustment,and the influence of self-supporting materials.It not only analyzes the progress in HER,but also provides guidance for synthesizing high-performance carbon-based transition metal catalysts.
