分析了电磁轨道炮发射时后坐运动的特征,将其运动分为3个时期:电枢膛内运动时期、电枢出膛后残余电能释放时期和惯性后坐时期;进一步将每个时期的后坐运动分为自由后坐运动与制退运动。分别分析3个时期身管后坐的运动特征,根据其运动方...分析了电磁轨道炮发射时后坐运动的特征,将其运动分为3个时期:电枢膛内运动时期、电枢出膛后残余电能释放时期和惯性后坐时期;进一步将每个时期的后坐运动分为自由后坐运动与制退运动。分别分析3个时期身管后坐的运动特征,根据其运动方程与力平衡方程,结合内弹道计算结果与发射器总体设计参数求解各时期运动规律。以某口径电磁轨道炮为例,在初始后坐阻力10 k N,后坐总行程20 mm的前提下,计算得到后坐阻力常数为22.728 k N,后坐总时间为92.32 ms,获得了后坐运动曲线。计算方法及结果能够为电磁轨道炮制退机与复进机的设计提供一定的指导依据。展开更多
In this paper, an overview of the theory of Mössbauer effect is covered, and the main hyperfine interactions parameters which affect the shape of the resultant Mössbauer spectrum are explained and il...In this paper, an overview of the theory of Mössbauer effect is covered, and the main hyperfine interactions parameters which affect the shape of the resultant Mössbauer spectrum are explained and illustrated as well. In principle, Mössbauer effect applies to any and all nuclides, but in practice, certain ideal properties are desirable;that is, the conditions for recoil-free emission and absorption of gamma rays must be optimized. Therefore, briefly discussed in this review, one of the most commonly used for practical and fundamental studies the 151Eu Mössbauer isotope. Also, the intermediate valence phenomena and their theoretical treatments are briefly discussed.展开更多
The η meson can be bound to atomic nuclei.Experimental search is discussed in the form of final state interaction for the reactions dp → 3 Heη and dd → 4 Heη.For the latter case tensor polarized deuterons were us...The η meson can be bound to atomic nuclei.Experimental search is discussed in the form of final state interaction for the reactions dp → 3 Heη and dd → 4 Heη.For the latter case tensor polarized deuterons were used in order to extract the s-wave strength.For both reactions complex scattering lengths are deduced： a 3 Heη = ± 10.7±0.8 ＋0.1 -0.5 ＋i· 1.5±2.6 ＋1.0-0.9 fm and a 4 Heη = [±（3.1±0.5）＋i·（0±0.5）] fm.In a two-nucleon transfer reaction under quasi-free conditions,p^ 27 Al → ^3 HeX,was investigated.The system X can be the bound 25 Mg η at rest.When a possible decay of an intermediate N （1535） is required,a highly significant bump shows up in the missing mass spectrum.The data give for a bound state a binding energy of 13.3±1.6 MeV and a width of σ=4.4±1.3 MeV.展开更多
文摘分析了电磁轨道炮发射时后坐运动的特征,将其运动分为3个时期:电枢膛内运动时期、电枢出膛后残余电能释放时期和惯性后坐时期;进一步将每个时期的后坐运动分为自由后坐运动与制退运动。分别分析3个时期身管后坐的运动特征,根据其运动方程与力平衡方程,结合内弹道计算结果与发射器总体设计参数求解各时期运动规律。以某口径电磁轨道炮为例,在初始后坐阻力10 k N,后坐总行程20 mm的前提下,计算得到后坐阻力常数为22.728 k N,后坐总时间为92.32 ms,获得了后坐运动曲线。计算方法及结果能够为电磁轨道炮制退机与复进机的设计提供一定的指导依据。
文摘In this paper, an overview of the theory of Mössbauer effect is covered, and the main hyperfine interactions parameters which affect the shape of the resultant Mössbauer spectrum are explained and illustrated as well. In principle, Mössbauer effect applies to any and all nuclides, but in practice, certain ideal properties are desirable;that is, the conditions for recoil-free emission and absorption of gamma rays must be optimized. Therefore, briefly discussed in this review, one of the most commonly used for practical and fundamental studies the 151Eu Mössbauer isotope. Also, the intermediate valence phenomena and their theoretical treatments are briefly discussed.
文摘The η meson can be bound to atomic nuclei.Experimental search is discussed in the form of final state interaction for the reactions dp → 3 Heη and dd → 4 Heη.For the latter case tensor polarized deuterons were used in order to extract the s-wave strength.For both reactions complex scattering lengths are deduced： a 3 Heη = ± 10.7±0.8 ＋0.1 -0.5 ＋i· 1.5±2.6 ＋1.0-0.9 fm and a 4 Heη = [±（3.1±0.5）＋i·（0±0.5）] fm.In a two-nucleon transfer reaction under quasi-free conditions,p^ 27 Al → ^3 HeX,was investigated.The system X can be the bound 25 Mg η at rest.When a possible decay of an intermediate N （1535） is required,a highly significant bump shows up in the missing mass spectrum.The data give for a bound state a binding energy of 13.3±1.6 MeV and a width of σ=4.4±1.3 MeV.
