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Research on the Distant Hybrids of Wheat Obtained via Low-Energy Ion-Beam Implantation
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作者 苌收伟 程玉红 +1 位作者 秦广雍 苏明杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第3期1821-1824,共4页
The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu 5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plants obtained whose protein content was higher than... The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu 5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plants obtained whose protein content was higher than 18.5 %, the highest one was 21.44 %. There were 3 plants obtained whose protein content was lower than 11.5%, the lowest one was 10.96%. We can see that the whole DNA of soybean transformed into wheat via ion beam implantation can induce the increase in wheat protein content dramatically. The result also shows that the transformation efficiency of different gene types of wheat receptor varies greatly that the implanting time has a certain effect on the efficiency of transformation. 展开更多
关键词 transformation via ion beam soy DNA distant hybrid
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Characteristics of a Gaussian focus embedded within spiral patterns in common-path interferometry with phase apertures
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作者 Yizhou Tan Ying Gu 《Advanced Photonics Nexus》 2023年第3期70-78,共9页
A phase-only method is proposed to transform an optical vortex field into desired spiral diffraction-interference patterns.Double-ring phase apertures are designed to produce a concentric high-order vortex beam and a ... A phase-only method is proposed to transform an optical vortex field into desired spiral diffraction-interference patterns.Double-ring phase apertures are designed to produce a concentric high-order vortex beam and a zeroth-order vortex beam,and the diffracted intensity ratio of two beams is adjustable between 0 and 1.The coherent superposition of the two diffracted beams generates a brighter Airy spot(or Poisson spot)in the middle of the spiral pattern,where the singularity for typical vortex beam is located.Experiments employing circular,triangular,and rectangular phase apertures with topological charges from 3 to 16 demonstrate a stable,compact,and flexible apparatus for vortex beam conversion.By adjusting the parameters of the phase aperture,the proposed method can realize the optical Gaussian tweezer function and the optical vortex tweezer function simultaneously along the same axis or switch the experimental setup between the two functions.It also has potential applications in light communication through turbulent air by transmitting an orbital angular momentum-coded signal with a concentric beacon laser. 展开更多
关键词 finite aperture diffraction phase-only beam transformation orbital angular momentum common-path interferometry optical manipulation light transmission through turbulent air
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Closed-form solution of beam on Pasternak foundation under inclined dynamic load 被引量:2
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作者 Yu Miao Yang Shi +1 位作者 Guobo Wang Yi Zhong 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2017年第6期596-607,共12页
The dynamic response of an infinite Euler–Bernoulli beam resting on Pasternak foundation under inclined harmonic line loads is developed in this study in a closed-form solution.The conventional Pasternak foundation i... The dynamic response of an infinite Euler–Bernoulli beam resting on Pasternak foundation under inclined harmonic line loads is developed in this study in a closed-form solution.The conventional Pasternak foundation is modeled by two parameters wherein the second parameter can account for the actual shearing effect of soils in the vertical direction.Thus,it is more realistic than the Winkler model,which only represents compressive soil resistance.However,the Pasternak model does not consider the tangential interaction between the bottom of the beam and the foundation;hence,the beam under inclined loads cannot be considered in the model.In this study,a series of horizontal springs is diverted to the face between the bottom of the beam and the foundation to address the limitation of the Pasternak model,which tends to disregard the tangential interaction between the beam and the foundation.The horizontal spring reaction is assumed to be proportional to the relative tangential displacement.The governing equation can be deduced by theory of elasticity and Newton’s laws,combined with the linearly elastic constitutive relation and the geometric equation of the beam body under small deformation condition.Double Fourier transformation is used to simplify the geometric equation into an algebraic equation,thereby conveniently obtaining the analytical solution in the frequency domain for the dynamic response of the beam.Double Fourier inverse transform and residue theorem are also adopted to derive the closed-form solution.The proposed solution is verified by comparing the degraded solution with the known results and comparing the analytical results with numerical results using ANSYS.Numerical computations of distinct cases are provided to investigate the effects of the angle of incidence and shear stiffness on the dynamic response of the beam.Results are realistic and can be used as reference for future engineering designs. 展开更多
关键词 beam Harmonic line load Pasternak foundation Tangential interaction between the beam and the foundation Fourier transform
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