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81.
形变双奇核178Ir转动带能级的旋称反转   总被引:1,自引:0,他引:1  
利用152Sm(31P,5nγ)178Ir反应产生并研究了双奇核178Ir的高自旋态.实验中进行了178Ir核的在束γ测量,包括γ射线的激发函数测量、X–γ和γ–γ符合测量.首次建立了双奇核178Ir基于πh9/2νi13/2和πh11/2νi13/2准粒子组态上的转动带能级纲图.发现在低自旋区,两个转动带能级均出现旋称反转.对此核区半退耦带的旋称反转作了简要的分析和讨论.  相似文献   
82.
Synthetic methods for 3-azabicyclo[3.1.0]hex-2-enes and 4-carbonylpyrroles have been developed that use copper-mediated/catalyzed reactions of N-allyl/propargyl enamine carboxylates under an O(2) atmosphere and involve intramolecular cyclopropanation and carbooxygenation, respectively. These methodologies take advantage of orthogonal modes of chemical reactivity of readily available N-allyl/propargyl enamine carboxylates; the complementary pathways can be accessed by slight modification of the reaction conditions.  相似文献   
83.
Excited states in the neutron-rich doubly-odd nucleus78As have been identified for the first time by proton-γ and γ-γ coincidence measurements via the76Ge(α, pn) reaction at 32, 36, and 40 MeV beam energy. Four levels have been found to decay with lifetimes in the nanosecond region. The 5(+) to (10+) states are ascribed to the (πg 9/2?νg 9/2) intruder two-quasiparticle configuration with some collective components in the 9(+) and (10+) states.  相似文献   
84.
利用能量为170MeV的35Cl束流,通过157Gd(35Cl,4n)熔合蒸发反应研究了188Tl的高自旋态能级结构.依据实验结果建立了188Tl基于πh9/2(?)vi13/2组态的转动带.根据双奇Tl核能级结构的相似性,指定了188Tlπh9/2(?)vi13/2扁椭球转动带的自旋值.结果表明在188Tl中,πh9/2(?)vi13/2扁椭球转动带在低自旋区具有旋称反转性质.利用包含了质子-中子剩余相互作用的准粒子-转子模型,定性地解释了πh9/2(?)vi13/2扁椭球转动带的低自旋区旋称反转现象.  相似文献   
85.
Based on the systematic investigation of the data available for nuclei with A≥ 40, a Z 1/3-dependence for the nuclear charge radii is shown to be superior to the generally accepted A 1/3 law. A delicate scattering of data around R c/Z 1/3 is inferred as owing to the isospin effect and a linear dependence of R c/Z 1/3 on N/Z (or (N - Z)/2) is found. This inference is well supported by the microscopic Relativistic Continuum Hartree-Bogoliubov (RCHB) calculation conducted for the proton magic Ca, Ni, Zr, Sn and Pb isotopes including the exotic nuclei close to the neutron drip line. With the linear isospin dependence provided by the data and RCHB theory, a new isospin-dependent Z 1/3 formula for the nuclear charge radii is proposed. Received: 23 September 2001 / Accepted: 21 January 2002  相似文献   
86.
利用能量为161—175MeV的32S束流,通过反应118Sn(32S,1p4n)产生了145Tb的高自旋态.进行了γ射线的激发函数、γγt符合测量.首先建议了由24条能级和42条γ跃迁组成的145Tb核的能级纲图,并指定了各条能级的自旋值及部分低位能级的宇称.用一个πh11/2价质子与144Gd核芯激发态的耦合定性地解释了145Tb的一些低位激发态.  相似文献   
87.
A new radionuclide quantification method is proposed on the basis of multiple gamma-ray detection, which is two or higher fold gamma-ray coincidence method. The coincidence method has so far been used for nuclear structure study. We apply this method for quantification of radioactive nuclei. The advantage of this method consists of high energy resolution and high sensitivity. It is successfully applied to nuclear waste analysis, neutron activation analysis and prompt gamma-ray analysis. The principle of the multiple gamma-ray detection method and future perspectives for an innovative pulsed neutron source and a new detector system will be presented.  相似文献   
88.
A neutron beam line for multiple prompt gamma-ray analysis was constructed at the Japan Atomic Energy Agency. A detector system for the MPGA was constructed at the C2-3-2 beam line in January 2005. It comprised eight (upgraded in March 2007) clover Ge detectors with a BGO Compton suppressor. High efficiency detector system provides an advantage in terms of the detection limit of MPGA when compared to the result of PGA. The supermirror neutron bender was improved and a supermirror neutron guide was installed upstream of the sample position.  相似文献   
89.
A short and efficient synthesis of enone 3, a key intermediate in the total synthesis of platencin (2), based on an intramolecular Diels-Alder reaction is described.  相似文献   
90.
Hirschhorn recently proved a pair of q-series identities that interlinked the coefficients of two infinite products. We use the theory of modular forms to extend his results from \(p=5\) to other primes and provide other examples of infinite products sharing similar properties.  相似文献   
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