The combination of the traditional pipe-bending technology and the CNC technology of machine tool there is no fixed size and material specifications. Moreover,make the pipe bending process automation. However,the non-...The combination of the traditional pipe-bending technology and the CNC technology of machine tool there is no fixed size and material specifications. Moreover,make the pipe bending process automation. However,the non-linear relationship between the bending moment and the sizes brings troubles in choosing an electric ma-chine of the CNC pipe-bending device. Therefore, this paper presents a formula to calculate the pipe-bending mo-ment, for improving the calculating efficiency and reducing the testing cost. The numerical simulation and experi-mental test were carried out to verify the accuracy of the formula, respectively. The result shows that the presentedformula is effective in solving the engineering problems.展开更多
It is the result of a systemic study about uniform hematite nanopallets with length of about 100 nm, width of about 30 nm, and thickness of less than 10 nm. The sample has superparamagnetic(SPM) properties above the b...It is the result of a systemic study about uniform hematite nanopallets with length of about 100 nm, width of about 30 nm, and thickness of less than 10 nm. The sample has superparamagnetic(SPM) properties above the blocking temperature of ～16 K. The temperature dependence of magnetization was well fitted by Bloch T^(3/2) law considering the dipolar interaction of the particles. The field dependence of magnetization was fitted with revised Langevin equation.The magnetization of the weak ferromagnetic(WF) canted spins contributes to the linear portion in the high field region;the surface uncompensated spins and the parasitic ferromagnetic moments due to the canted spins both contribute to the particle moments and the superparamagnetic behavior.展开更多
This paper aims at the elastic buckling of multilayered thin-walled conical shells with power-law distributed material properties under the axial load and lateral pressure based on the experimental study of palm trunk...This paper aims at the elastic buckling of multilayered thin-walled conical shells with power-law distributed material properties under the axial load and lateral pressure based on the experimental study of palm trunks. The material properties of the shells are assumed to vary continuously in the radial direction. Relations and analytical approaches for linear buckling response are presented by using the layer-wise shell theory. The buckling behaviors of the conical shells subjected to axial and transverse loads are investigated. Parametric study in geometry(relative thickness, relative stiffness and cone angle) is performed to enhance the overall buckling resistance and minimize the weight. Numerical results show the possibility to achieve larger load-carrying capacity by simultaneously optimizing the material and geometric parameters based on the structure of palm trunks.展开更多
基金supported by Torch Plan of Ministry of Science and Technology,(No. 2012GH571660)
文摘The combination of the traditional pipe-bending technology and the CNC technology of machine tool there is no fixed size and material specifications. Moreover,make the pipe bending process automation. However,the non-linear relationship between the bending moment and the sizes brings troubles in choosing an electric ma-chine of the CNC pipe-bending device. Therefore, this paper presents a formula to calculate the pipe-bending mo-ment, for improving the calculating efficiency and reducing the testing cost. The numerical simulation and experi-mental test were carried out to verify the accuracy of the formula, respectively. The result shows that the presentedformula is effective in solving the engineering problems.
基金financially supported by the National Natural Science Foundation of China (Nos. 11674023, 51371015,51331002, and 51501004)Beijing Municipal Science and Technology Project (No. 217111000220000)
文摘It is the result of a systemic study about uniform hematite nanopallets with length of about 100 nm, width of about 30 nm, and thickness of less than 10 nm. The sample has superparamagnetic(SPM) properties above the blocking temperature of ～16 K. The temperature dependence of magnetization was well fitted by Bloch T^(3/2) law considering the dipolar interaction of the particles. The field dependence of magnetization was fitted with revised Langevin equation.The magnetization of the weak ferromagnetic(WF) canted spins contributes to the linear portion in the high field region;the surface uncompensated spins and the parasitic ferromagnetic moments due to the canted spins both contribute to the particle moments and the superparamagnetic behavior.
基金the National Natural Science Foundation of China(No.50975090)the Torch Program of Ministry of Science and Technology of China(No.2012GH571660)
文摘This paper aims at the elastic buckling of multilayered thin-walled conical shells with power-law distributed material properties under the axial load and lateral pressure based on the experimental study of palm trunks. The material properties of the shells are assumed to vary continuously in the radial direction. Relations and analytical approaches for linear buckling response are presented by using the layer-wise shell theory. The buckling behaviors of the conical shells subjected to axial and transverse loads are investigated. Parametric study in geometry(relative thickness, relative stiffness and cone angle) is performed to enhance the overall buckling resistance and minimize the weight. Numerical results show the possibility to achieve larger load-carrying capacity by simultaneously optimizing the material and geometric parameters based on the structure of palm trunks.
