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提出了一种基于像差特征分析的变焦系统共轴性装调方法。针对某型20倍变焦光学系统的装调,在分析变焦光学系统装调要求的基础上,通过采用光学定心加工技术,提高变焦系统各镜组内光学元件的同轴度;采用Zygo干涉仪,检测变焦系统在长短焦位置的像差特性分布;借助CodeV软件仿真计算各光学元件在系统中的公差灵敏度分布,并确定产生像差影响的敏感光学元件;在中心偏测量仪上,完成最终光学系统像质的调整。此外,还设计了一种变焦光学系统各动组间同轴度调试装置,对变焦相机主镜筒机械内孔轴线与直线导轨的平行性进行了精确测量,保证了动组组元光轴的同轴精度。装调结果表明:变焦系统成像质量有明显改善,像面一致性得到保证,长短焦轴上传递函数值分别优于技术要求值0.45和0.55,长短焦轴外0.7视场传递函数值优于0.25和0.35,实现了高精度装调,验证了该方法的可靠性。 相似文献
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The ^8Li(p, d)^7 Li reaction plays an important role in the inhomogeneous Big Bang nucleosynthesis and in the seed-nuclide production phase for the r-process. For the first time, its angular distribution at backward angles was measured in inverse kinematics at Ec.m.=4.0 MeV by using an ^8Li secondary beam. The result of measurement includes the contributions of ^8Li(p, d0)^7Li and ^8Li(p, d1)^7Li^*. The ^8Li(p, d0)^7Li component is estimated to be 40%-58% in the mixture angular distribution by analysing the measured result. 相似文献
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The ^13 N+p elastic resonance scattering has been studied at the secondary radioactive beam facility of CIAE in inverse kinematics via a thick-target method. The excitation function for the ^13N(p,p) scattering was obtained in the energy interval of Ecru ≈0.5-3.2 MeV with a ^13 N secondary beam of (47.8±1.5) MeV. Careful analysis of the secondary beam components and extensive Monte-Carlo simulations enable the resolution of the experimental proton spectra. The resonance parameters for five low-lying levels in ^14 O were deduced by Rmatrix fitting calculations with MULTI7 and SAMMY-M6-BETA. The present results show general agreement with those from a recent similar work, and thus confirm the observation of a new 0^- level at 5.7 MeV in 140 with an improved width of 400(45) keV. 相似文献
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This paper described the nuclear astrophysical studies using the unstable ion beam facility GIRAFFE in CIAE, by indirect measurements. We measured the angular distributions for some single proton or neutron transfer reactions, such as 7Be(d,n)8B, 11C(d,n)12N, 8Li(d,p)9Li and 13N(d,n)14O in inverse kinematics, and derived the astrophysical S-factors or reaction rates of 7Be(p,γ)8B, 11C(p,γ)12N, 8Li(n,γ)9Li, 13N(p,γ)14O by asymptotic normalization coefficient, spectroscopic factor, and R-matrix approach at astrophysically relevant energies. Some most recent progress of nuclear astrophyiscal work in CIAE are also summarized. 相似文献
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为了了解简单流体混合物在微孔介质中的流动和传递性质,对微孔中氩和氪流体混合物的扩散系数进行了计算机模拟和关联模型研究.运用平衡分子动力学方法模拟了宏量条件下饱和氩流体的扩散系数和恒温氪流体的扩散系数,模拟值与文献实验值符合良好,从而程序的正确性得到验证.然后,采用类似Bitsanis等人的方法模拟了平板湿壁微孔中氩和氪等摩尔流体混合物在不同对比温度、不同对比密度以及不同对比孔径条件下的扩散系数,发现孔径很小的时候扩散系数会急剧的增大.同时基于这些模拟值,参考CE理论和Heyes关系式,以对比温度、对比密度以及对比孔径为变量,关联出两个简单流体等摩尔混合物在微孔中扩散系数的计算模型.模型的计算结果与计算机模拟值能够较好地吻合. 相似文献
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Temperature dependence of nuclear decays in metallic environments is a controversial issue. We measured the temperature dependence of the β^+-decay half-life of ^22Na implanted into the metal host of palladium. It is found that the β^+-decay half-life of ^22Na in the metal Pd cooled to T = 15 K is shorter by 0.46(14)% than that at room temperature. The result is consistent in sign with, but dearly smaller than, the estimated one by the Debye model. 相似文献
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为了了解简单流体混合物在微孔介质中的流动和传递性质 ,对微孔中氩和氪流体混合物的扩散系数进行了计算机模拟和关联模型研究 .运用平衡分子动力学方法模拟了宏量条件下饱和氩流体的扩散系数和恒温氪流体的扩散系数 ,模拟值与文献实验值符合良好 ,从而程序的正确性得到验证 .然后 ,采用类似Bitsanis等人的方法模拟了平板湿壁微孔中氩和氪等摩尔流体混合物在不同对比温度、不同对比密度以及不同对比孔径条件下的扩散系数 ,发现孔径很小的时候扩散系数会急剧的增大 .同时基于这些模拟值 ,参考CE理论和Heyes关系式 ,以对比温度、对比密度以及对比孔径为变量 ,关联出两个简单流体等摩尔混合物在微孔中扩散系数的计算模型 .模型的计算结果与计算机模拟值能够较好地吻合 相似文献
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