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951.
Linearity Requirement for a Linear Frequency Modulation Lidar 总被引:1,自引:0,他引:1
The nonlinear of the frequency modulation in linear frequency modulation (LFM) lidar seriously affects the accuracy of range and velocity. We describe the influence of nonlinear of the frequency modulation on the accuracy. The frequency-domain analysis of heterodyne signal is used to deduce the linearity requirement for LFM lidar. 相似文献
952.
Photochemical Reactions of Cyclopentadienylbis(ethene)rhodium with Benzene Derivatives During UV irradiation of [CpRh(C2H4)2] ( 1 ) (Cp = η5‐C5H5) in hexane in the presence of hexamethylbenzene the di‐ and trinuclear arene bridged complexes [(CpRh)2(μ‐η3 : η3‐C6Me6)] ( 3 ) and [(CpRh)3(μ3‐η2 : η2 : η2‐C6Me6)] ( 4 ) are formed besides known [CpRh(η4‐C6Me6)] ( 2 ). It was shown by a separate experiment that 3 besides small amounts of 4 is formed by attack of photochemically from 1 arising CpRh fragments at the free double bond of the η4‐bonded benzene ring in 2 . Irradiation of 1 in the presence of diphenyl (C12H10) affords the compounds [(CpRh)2(μ‐η3 : η3‐C12H10)] ( 5 ) and [(CpRh)3(μ3‐η2 : η2 : η2‐C12H10)] ( 6 ) as analogues of 3 and 4 , in the presence of triptycene (C20H14) only [(CpRh)2(μ‐η3 : η3‐C20H14)] ( 7 ) is obtained; the bridging in 5 , 6 , and 7 always occurs via the same six‐membered ring of the corresponding ligand system. During the photochemical reaction of 1 in the presence of styrene (C8H8) substitution of the ethene ligands by the vinyl groups with formation of [CpRh(C2H4)(η2‐C8H8)] ( 8 ) and known [CpRh(η2‐C8H8)2] ( 9 ) is observed exclusively. The new complexes were characterized analytically and spectroscopically, in the case of 3 also by X‐ray structure analysis. 相似文献
953.
By studying the \begin{document}$\eta_c$\end{document} ![]()
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exclusive decay to double glueballs, we introduce a model to phenomenologically mimic the gluon-pair-vacuum interaction vertices, namely the \begin{document}$0^{++}$\end{document} ![]()
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model. Based on this model, we study glueball production in pseudoscalar quarkonium decays, explicitly \begin{document}$\eta_c \to f_0(1500)\eta(1405)$\end{document} ![]()
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, \begin{document}$\eta_b\to f_0(1500)\eta(1405)$\end{document} ![]()
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, and \begin{document}$\eta_b\to f_0(1710)\eta(1405)$\end{document} ![]()
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processes. Among them \begin{document}$f_0(1500)$\end{document} ![]()
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and \begin{document}$f_0(1710)$\end{document} ![]()
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are well-known scalars possessing large glue components, while \begin{document}$\eta(1405)$\end{document} ![]()
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is a potential candidate for a pseudoscalar glueball. The preliminary calculation results indicate that these processes are marginally accessible in the presently running experiments BES III, BELLE II, and LHCb. 相似文献
954.
Analytical expressions of non-relativistic static multipole polarizabilities for hydrogen-like ions 下载免费PDF全文
Analytical formulas for the static multipole polarizabilities of hydrogen-like ions are derived by using the analytical wave functions and the reduced Green function and by applying a numerical fitting procedure.Our results are then applied to the studies of blackbody radiation shifts to atomic energy levels at different temperatures.Our analytical results can be served as a benchmark for other theoretical methods. 相似文献
955.
Makarov A. S. Goncharova E. V. Afonin G. V. Qiao J. C. Kobelev N. P. Khonik V. A. 《JETP Letters》2020,111(10):586-590
JETP Letters - A method is proposed to calculate the temperature dependence of the unrelaxed shear modulus of high-entropy bulk metallic glasses from differential scanning calorimetry data. The... 相似文献
956.
The transport of a chain of charged particles with a transverse degree of freedom is investigated in a 2D asymmetric potential. Here, the energy of the periodic driving force is converted into motion in the vertical direction. The analysis exhibits a transition from stick-slip motion to periodic oscillation. The chain velocity can be controlled to an optimized value by adjusting system parameters, such as the amplitude and frequency of the periodic force. The existence of a resonance platform indicates resonance between the motion of the chain and the periodic force as coupling strength increases adiabatically. The atomic configuration and the transverse degree of freedom also play key roles in the control. 相似文献
957.
We propose a new microfluid chip for transporting micro and nano particles. The device consists of chemical stripe pathways full of fuel species, which can be realized in experiments by chemical surface reactions that form spatiotemporal patterns. A mesoscopic model is constructed to simulate the transport dynamics of nanodimers passing through the chip. It is found that the increases of the volume fraction and radius of the dimer both decrease the first reach time although the underlying mechanisms are different: the volume fraction affects the probability of touching and entering the chip while the radius determines the self-propulsion within the chip.The transport efficiency is influenced by the size of the particles. 相似文献
958.
为了研究欧姆损耗对高频真空电子器件工作特性的影响,首先推导频率色散表面阻抗边界在三维共形粒子模拟软件UNIPIC-3D中的实现原理,并通过对有耗边界矩形谐振腔和圆波导进行模拟验证了该阻抗边界算法的正确性.采用有耗共形UNIPIC-3D模拟相对论太赫兹表面波振荡器和低电压平板格栅返波振荡器.模拟结果表明,对于表面波振荡器和平板BWO这种电磁场集中在金属慢波结构附近的太赫兹真空电子器件,欧姆损耗会对器件的运行带来极大影响,对于采用铜材料的器件,输出功率会下降一半左右,器件起振时间出现延迟,但器件工作频率几乎不变.为了提高相对论太赫兹表面波振荡器的效率,在二极管和慢波结构之间增加了反射腔,模拟结果表明,在考虑器件表面损耗的条件下,器件的工作频率保持不变,输出功率由41 MW提高到60 MW. 相似文献
959.
960.