The combined effects of Sm^(3+)substitution together with the addition of 3 wt%Bi_(2)O_(3)endow Mg Cd ferrites with excellent magnetic permeability and dielectric permittivity.Various concentrations of Sm^(3+)(x=0,0.0...The combined effects of Sm^(3+)substitution together with the addition of 3 wt%Bi_(2)O_(3)endow Mg Cd ferrites with excellent magnetic permeability and dielectric permittivity.Various concentrations of Sm^(3+)(x=0,0.03,0.06,0.09,0.12and 0.15)were employed to modify the permeability(μ)and permittivity(ε)of the Mg Cd ferrites.X-ray diffraction,scanning electron microscopy(SEM),vibrating sample magnetometry and vector network analysis techniques were used to characterize the samples.The measurement results reveal that the ferrites processed a saturation magnetization of up to 36.8 emu/g and coercivity of up to 29.2 Oe via the conventional solid-state reaction method.The surface morphology SEM confirms that with increasing Sm^(3+)concentration,the grain shape changes from a polygon to a circle.Moreover,the dielectric permittivity can reach a value of 23.The excellent properties obtained in Sm^(3+)-substituted Mg ferrites suggest that they could be promising candidates for modern high-frequency antenna substrates or multilayer devices.展开更多
A novel optical instrument is proposed and studied to measure the deformation of each connection point for a mirror, which includes 24 multi-matrix base units and can be used in millimeter-scale signal reflection syst...A novel optical instrument is proposed and studied to measure the deformation of each connection point for a mirror, which includes 24 multi-matrix base units and can be used in millimeter-scale signal reflection systems.Experimental investigations reveal that the error of measurement is σ=8.7×10^(-3) mm at a distance of 5 500 mm, which allows to measure the linear deformation of a radiotelescope with the mirror diameter of 70 m.展开更多
A photoelectric autocollimator with high accuracy and extended measurement range based on the quadrangular pyramid is proposed,and the corresponding algorithms are also deduced.A new image processing algorithm has bee...A photoelectric autocollimator with high accuracy and extended measurement range based on the quadrangular pyramid is proposed,and the corresponding algorithms are also deduced.A new image processing algorithm has been proposed to improve the accuracy,and the corresponding errors are also estimated,the error does not exceed half a pixel when the distance between the marks more than two radii.The experimental results have verified that the measurement range of the proposed two-dimensional(2D)quadrangular pyramid photoelectric autocollimator can be increased 2 times than that of the flat mirror photoelectric autocollimator from 10′to 15′.The accuracy is better than 1″when the deflection is less than 15′.展开更多
基金the National Key Research and Development Program of China(Grant No.2018YFE0115500)the National Natural Science Foundation of China(Grant Nos.51902037 and 62005033)+2 种基金the Open Foundation of State Key Laboratory of Electronic Thin Films and Integrated Devices(Grant No.KFJJ201912)the Science and Technology Project Affiliated to the Education Department of Chongqing Municipality(Grant No.KJQN201900615)the Nature Science Foundation of Chongqing(Grant No.cstc2019jcyjmsxm X0696)。
文摘The combined effects of Sm^(3+)substitution together with the addition of 3 wt%Bi_(2)O_(3)endow Mg Cd ferrites with excellent magnetic permeability and dielectric permittivity.Various concentrations of Sm^(3+)(x=0,0.03,0.06,0.09,0.12and 0.15)were employed to modify the permeability(μ)and permittivity(ε)of the Mg Cd ferrites.X-ray diffraction,scanning electron microscopy(SEM),vibrating sample magnetometry and vector network analysis techniques were used to characterize the samples.The measurement results reveal that the ferrites processed a saturation magnetization of up to 36.8 emu/g and coercivity of up to 29.2 Oe via the conventional solid-state reaction method.The surface morphology SEM confirms that with increasing Sm^(3+)concentration,the grain shape changes from a polygon to a circle.Moreover,the dielectric permittivity can reach a value of 23.The excellent properties obtained in Sm^(3+)-substituted Mg ferrites suggest that they could be promising candidates for modern high-frequency antenna substrates or multilayer devices.
基金supported by the National Key R&D Program of China(Nos.2018YFF01010202 and 2018YFF01010201)the National Natural Science Foundation of China(Nos.61705027 and 11704053)+2 种基金the Innovation Leader Talent Project of Chongqing Science and Technology(No.CSTC-CXLJRC201711)the Basic Research Project of Chongqing Science and Technology Commission(Nos.CSTC-2017csmsA40017,CSTC-2015jcy-BX0068 and CSTC-2018jcyjax0619)the Science and Technology Project Affiliated to the Education Department of Chongqing Municipality(Nos.KJZH17115,KJQN201800626,KJ1704104 and KJ1704106)
文摘A novel optical instrument is proposed and studied to measure the deformation of each connection point for a mirror, which includes 24 multi-matrix base units and can be used in millimeter-scale signal reflection systems.Experimental investigations reveal that the error of measurement is σ=8.7×10^(-3) mm at a distance of 5 500 mm, which allows to measure the linear deformation of a radiotelescope with the mirror diameter of 70 m.
基金supported by the National Key R&D Program of China(No.2020YFC2003301)the National Natural Science Foundation of China(Nos.62005033,61705027,11704053,51902037 and 61901069)+2 种基金the Government of the Russian Federation(No.08-08)the Basic Research Project of Chongqing Science and Technology Commission(No.CSTC-2020jcyj-msxm0603)the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJQN202000609)。
文摘A photoelectric autocollimator with high accuracy and extended measurement range based on the quadrangular pyramid is proposed,and the corresponding algorithms are also deduced.A new image processing algorithm has been proposed to improve the accuracy,and the corresponding errors are also estimated,the error does not exceed half a pixel when the distance between the marks more than two radii.The experimental results have verified that the measurement range of the proposed two-dimensional(2D)quadrangular pyramid photoelectric autocollimator can be increased 2 times than that of the flat mirror photoelectric autocollimator from 10′to 15′.The accuracy is better than 1″when the deflection is less than 15′.
