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1.
光学薄膜技术作为现代光学的一个重要分支,近年来发展十分迅速。对光学薄膜参数的测试又是一项十分关键性的工作,它对薄膜理论的建立,膜系的设计,产品的研制,镀制工艺的提高和改进以及实际应用的开发都有其指导意义。因此,对光学薄膜测试方法的研究和测试仪器的研制,急在眉睫。薄膜反射率的测量,可以检验产品在实用上的可靠性和理论上的正确性。  相似文献   

2.
据报导,日本索尼公司新近制成一种大屏幕彩色电视显示器。屏幕的对角线是81.7厘米,高54.5厘米,宽69.1厘米,图象面积3766平方厘米,是迄今报导的世界上最大的显象管。 这种显象管也是采用单枪三束,140°偏转角。但由于电子束发生系统的结构是全新的,所以象点的尺寸比过去的大型显示器小  相似文献   

3.
《Nuclear Physics A》1998,636(2):209-223
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4.
Predictions are made for the spectra associated with the (πh 11/2) n configuration whenn=4, 5 and 6. Since 64 146 Gd82 actsas if it is a closed shell, these states are expected to be low-lying in the nuclei 68 150 Er82, 69 151 Tm82 and 70 152 Yb82. The residualh 11/2 interaction is taken from the experimental spectrum of 66 148 Dy82 and it is shown that this conserves seniority to a high degree. Arguments are given as to why configuration mixing may be hard to detect from a study of the energy levels alone. TheM1 selection rule and the number dependence of theE2 transition rates within the identical nucleonh 11/2 configuration are discussed and it is pointed out that seniority isomers should be seen in these nuclei. This prediction provides a stringent test of the configuration assignment. Formulae are given and estimates are made for the energies of theπg 7/2 andπd 5/2-hole states.  相似文献   

5.
High-spin states of115Sb were studied by inbeamγ-ray spectroscopy using the89Y (29Si, 2pn) fusionevaporation reaction at a beam energy of 108 MeV. The experiments includedγ-γ coincidence and directional correlation of oriented nuclei (DCO) ratio measurements using six BGO Compton suppressed Ge detectors. An intruderΔJ=2 rotational band has been identified for the first time and it is interpreted as the h11/2 proton coupled to a two particle-two hole (2p ? 2h) deformed state of the114Sn core. A ΔJ=1 rotational band based on the 2p ? 1h, π{g 7 2/2 ?g 9 2/?1 }, configuration has been extended to the 29/2+ state at an excitation energy of 5241 keV.  相似文献   

6.
引言本文是作者在慕尼黑技术大学串列加速器实验室从事远离β稳定线核谱研究的简单介绍。H.Morinaga 教授领导的实验组,利用该组建造的线性后加速器得到性能优良的Ni 束,通过以下核反应~(58)Ni(233…250MeV)→~(90,91,92)Zr,~(93)Nb,~(92,94)MO进行了一系列新的极丰质子核(质子结合能低于中子结合能)的核谱研究。所用实验方法是最基本的在束和离束γ射线谱学方法。结果在N≈82区建立了4个新核素(~(146)Dy,~(147)Ho,~(148)Er 和~(150)Er)的转晕线退激发能级图和14个新核素(~(144、144m、145、146)Tb,~(145、146)Dy,~(146、147、148、150)Ho,~(148、150)Er 和~(148、150)Tm)的衰变。  相似文献   

7.
Magnetoresistivity, magnetic, susceptibility and high field magnetization measurements were performed on the amorphous Mn x Pd82–x Ge18 alloys for 1x7. These amorphous alloys were prepared by radio frequency (R. F.) sputtering using argon, depositing onto fused quartz substrates to a thickness of about 20 microns. The negative magnetoresistivity is approximately proportional to the square of the magnetization and the susceptibility obeying the Curie-Weiss law between 18 and 293 K. These results lead to the conclusion that a Kondo-type s-d exchange interaction exists in the amorphous Mn-Pd-Ge alloys and the d-d, spin correlation between magnetic atoms is, in general, weaker in the amorphous alloys than in the corresponding crystalline alloys.  相似文献   

8.
9.
Shape coexistence around the Z=82 closed proton shell, probed via the fine structure in the α-decay of even–even nuclei, is discussed. The power of α-decay studies is demonstrated by presenting the results from a number of decay experiments of Rn isotopes performed at ISOLDE. The total body of experimental evidence on α-decay of even–even nuclei in the Pb region is used to illuminate, through the α-decay reduced widths of the ground state to ground state transitions and through the hindrance factors of the fine structure, the role of multi-particle multi-hole proton excitations across the Z=82 shell. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

10.
11.
(82)~Se的2νββ衰变寿命是双β衰变中第一个直接测量到的实验结果.本文利用双核子机制以及简化的壳模型波函数计算给出了82Se的2νββ衰变寿命的理论值,适当地调整壳模型计算中的参量,可获得与实验符合较好的理论半寿命。  相似文献   

12.
陈泽  张小平  杨洪应  郑强  陈娜娜  支启军 《物理学报》2014,63(16):162301-162301
利用提出的远离稳定线附近的原子核β-衰变寿命的指数规律理论计算公式,对N=82附近快中子过程中等待点核素的β-衰变寿命进行了理论计算,比较了所获得的计算结果与最新的理论结果和实验结果并加以讨论.研究表明,相对于理论复杂和计算时间长的微观理论计算而言,利用考虑壳效应的远离稳定线的原子核β-衰变寿命指数规律理论计算公式能较快且准确地得出快中子俘获过程(R过程)等待点核素的β-衰变寿命.这能为R过程核素合成网络计算研究提供有效可靠的重要物理输入,并对今后天体中核素的合成研究具有重要意义.  相似文献   

13.
The Mössbauer measurements of both57Fe and161Dy in Dy12Fe82B6 system are reported. The presence of B exceeds the magnetic hyperfine fields at both57Fe and161Dy nuclei as compared to corresponding pure metals Fe and Dy respectively. The only small excess of the hyperfine field at57Fe nucleus is observed. The excess at161Dy nucleus is about 12% of the free ion Dy3+ value.  相似文献   

14.
内嵌金属富勒烯以其独特的几何结构与电子结构预示其在电子、光电子以及医疗领域有重大的应用前景而受到研究者格外的关注. 详细描述了内嵌金属富勒烯的高效率生产的制备过程, 并通过测定和拟合在低温(25K)下Y@C82的不同k取值范围的EXAFS谱, 可以得到Y@C82中的Y的最近邻和次近邻配位壳层的结构参数, 还可以得知Y-C两个壳层的配位距离基本没有随k的取值范围变化, Y@C82的两个壳层的原子分布即使在低温下也存在比较大的无序.  相似文献   

15.
82Se的2νββ衰变寿命是双β衰变中第一个直接测量到的实验结果.本文利用双核子机制以及简化的壳模型波函数计算给出了82Se的2νββ衰变寿命的理论值,适当地调整壳模型计算中的参量,可获得与实验符合较好的理论半寿命.  相似文献   

16.
The neutron capture reaction on a neutron-rich near closed-shell nucleus 82Ge may play an important role in the r-process following the fallout from nuclear statistical equilibrium in core-collapse supernovae.By carrying out a DWBA analysis for the experimental angular distribution of 82Ge(d, p)83Ge reaction we obtain the single particle spectroscopic factors, S2,5/2 and S0,1/2 for the ground and first excited states of 83Ge=82Ge(⊕)n, respectively. And then these spectroscopic factors are used to calculate the direct capture cross sections for the 82Ge(n, γ)83Ge reaction at energies of astrophysical interest. The optical potential for neutron scattering on unstable nucleus 82Ge is not known experimentally. We employed a real folding potential which was calculated by using the proper 82Ge density distribution and an effective nucleon-nucleon force DDM3Y.The neutron capture reactions on neutron-rich closed-shell nuclei are expected to be dominated by the direct capture to bound states. We will show that the direct capture rates on these nuclei are sensitive to the structure of the low-lying states.  相似文献   

17.
采用分子动力学(MD)模拟计算,对Pd82Si18合金快凝过程中基本原子团簇的遗传特性、演化趋势和结构稳定性进行了研究.团簇类型指数法(CTIM)分析表明:非晶固体中Si原子为中心的(102/14418/1551)双帽阿基米德反棱柱(BSAP)团簇数目占据优势.快凝过程中,BSAP结构团簇具有最大的遗传分数,并且其他以Si原子为中心的Kasper团簇大多都会向BSAP结构团簇转变.通过对Si原子为中心的Kasper基本团簇电子性质第一性原理计算发现,体系中BSAP团簇的结合能最低,结构稳定性较高,与分子动力学计算结果一致.  相似文献   

18.
The ground-state ionization potentials of different isoelectronic sequences are calculated systemically with the multi-configuration Dirac-Fock method. The relativistic corrections, Breit and QED effects are included in the calculation. These results are compared with the scanty existing theoretical and experimental data in the literature, Analytical expressions are obtained for expressing our theoretical data along the different sequences.  相似文献   

19.
在0—300℃范围内考查了非晶Fe_(82)Si_5B_(13)合金的磁导率等温弛豫动力学行为,给出了等时弛豫谱,观察到四个弛豫峰。测量表明,总的磁导率弛豫由两种弛豫过程组成,即对于退磁可逆的普通减落和对于退磁不可逆的磁导率连续衰减。计算了弛豫时间和激活能的分布,表明弛豫时间和激活能有宽的分布。普通减落和磁导率衰减过程的最可几激活能分别为1.0eV和1.4eV。对退火的样品,观察到磁导率先是增大而后是衰减的广义cross-over效应。  相似文献   

20.
AStudyonYttriumContainingFullereneYC_(82)UsingLaserAblationMassSpectroscopy¥DONGGuoxuan;WANGShiliang;DAISongtao;LIChunming;CH...  相似文献   

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