According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spe...According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spectral shift of the electronic absorption spectra is deduced. Furthermore, the lowest transition of p-nitroaniline （pNA） in water is investigated by time-dependent density functional theory method. In addition, the details of excited state properties of pNA are discussed. Using our novel expression of the spectral shift, the value of -0.99 eV is obtained for π→π^＊ transition in water, which is in good agreement with the available experimental result of -0.98 eV.展开更多
A beam stabilization algorithm was proposed for low cost satcom-on-the-move （SOTM） to stabilize the vehicle-mounted antenna beam. The proposed algorithm utilizes the nonlinear observel to estimate the vehicle＇s att...A beam stabilization algorithm was proposed for low cost satcom-on-the-move （SOTM） to stabilize the vehicle-mounted antenna beam. The proposed algorithm utilizes the nonlinear observel to estimate the vehicle＇s attitude information based on inertial measurement unit. Then the estimated angles and angular velocities are used to stabilize the antenna beam. Experiment results show tha｜ the proposed algorithm can stabilize the antenna beam when the tracking information is available, indicating that it is competent to the SOTM system.展开更多
An experimental device able to determine the moisture content of wood usingX-ray attenuation is used to study the imbibition of beech samples (Fagus silvatica). The apparatusincludes an X-ray generator, a protective t...An experimental device able to determine the moisture content of wood usingX-ray attenuation is used to study the imbibition of beech samples (Fagus silvatica). The apparatusincludes an X-ray generator, a protective tube, collimating plates and a 50 mm detector. Detectedparticles can be categorised by energy (accuracy of the order of 20%) or by position (accuracy 100μm). The independent choice of both the energy spectrum (through the voltage) and the counting rate(through the current intensity) makes the installation very flexible. However, a rigorous treatmentis necessary to deal with the attenuation of a polychromatic spectrum. The appropriate calculationsare presented and validated with homogeneous samples made of wood and water. In addition, someresults are presented with samples heterogeneous in density and moisture content. Finally, theexperimental device is used to study the evolution of moisture content during saturationexperiments, for which the moisture migration is mainly due to capillary forces. The geometricalconfiguration was so arranged that the transfer can be studied in two directions simultaneously.展开更多
A system whose energy is not conserved is called nonconservative. To investigate if there exists a con- served quantity that has the same dimension as energy and is positively definite, the author analyzed the bending...A system whose energy is not conserved is called nonconservative. To investigate if there exists a con- served quantity that has the same dimension as energy and is positively definite, the author analyzed the bending vibration of an axially moving beam with geometric nonlinearity. Based on the governing equation, the energy was proven to be not conserved in the case where the beam has two simply supported or fixed ends. A definitely positive quantity with the energy dimension was defined. The quantity was verified to remain a constant during the motion. The investigation indicates that an energy-like conserved quantity may exist in a nonlinear nonconservative continuous system.展开更多
基金ACKNOWLEDGMENTS This work was supported Science Foundation of China by the National Natural （No.91016002）.
文摘According to the nonequilibrium solvation theory studies, a constrained equilibrium principle is introduced and applied to the derivations of the nonequilibrium solvation energy, and a reasonable expression of the spectral shift of the electronic absorption spectra is deduced. Furthermore, the lowest transition of p-nitroaniline （pNA） in water is investigated by time-dependent density functional theory method. In addition, the details of excited state properties of pNA are discussed. Using our novel expression of the spectral shift, the value of -0.99 eV is obtained for π→π^＊ transition in water, which is in good agreement with the available experimental result of -0.98 eV.
基金This work was supported in part by the National Natural Science Foundation of China under grant numbers 61179004,61179005 and 61401471
文摘A beam stabilization algorithm was proposed for low cost satcom-on-the-move （SOTM） to stabilize the vehicle-mounted antenna beam. The proposed algorithm utilizes the nonlinear observel to estimate the vehicle＇s attitude information based on inertial measurement unit. Then the estimated angles and angular velocities are used to stabilize the antenna beam. Experiment results show tha｜ the proposed algorithm can stabilize the antenna beam when the tracking information is available, indicating that it is competent to the SOTM system.
文摘An experimental device able to determine the moisture content of wood usingX-ray attenuation is used to study the imbibition of beech samples (Fagus silvatica). The apparatusincludes an X-ray generator, a protective tube, collimating plates and a 50 mm detector. Detectedparticles can be categorised by energy (accuracy of the order of 20%) or by position (accuracy 100μm). The independent choice of both the energy spectrum (through the voltage) and the counting rate(through the current intensity) makes the installation very flexible. However, a rigorous treatmentis necessary to deal with the attenuation of a polychromatic spectrum. The appropriate calculationsare presented and validated with homogeneous samples made of wood and water. In addition, someresults are presented with samples heterogeneous in density and moisture content. Finally, theexperimental device is used to study the evolution of moisture content during saturationexperiments, for which the moisture migration is mainly due to capillary forces. The geometricalconfiguration was so arranged that the transfer can be studied in two directions simultaneously.
文摘A system whose energy is not conserved is called nonconservative. To investigate if there exists a con- served quantity that has the same dimension as energy and is positively definite, the author analyzed the bending vibration of an axially moving beam with geometric nonlinearity. Based on the governing equation, the energy was proven to be not conserved in the case where the beam has two simply supported or fixed ends. A definitely positive quantity with the energy dimension was defined. The quantity was verified to remain a constant during the motion. The investigation indicates that an energy-like conserved quantity may exist in a nonlinear nonconservative continuous system.
