Embedded cell model of three-dimensional two-phase composites

An embedded cell model is presented to obtain the effective elastic moduli and the elastic-plastic stress-strain relations of three-dimensional two-phase particulate composites. Each cell consists of an ellipsoidal inclusion surrounded by a finite ellipsoidal matrix that embedded in an infinite matrix. When both matrix and particle are elastic, the effective elastic moduli are derived which is an exact analytic formula without any simplified approximation that can be expressed in an explicit form. Further, the elastic-plastic stress-strain relations are obtained for spherical cells and oblate spheroid cells, in which the matrix is elastic and the particle is elastic-plastic. In addition, the macroscopic elastic-plastic constitutive relation of particle reinforced composites (PRC) is investigated by a systematic approach [1] in which the matrix is elastic-plastic and the particle is elastic.

超重核~(294)118和~(291)116及其α衰变链上各核素半衰期的研究

运用推广的液滴模型(GLDM)确定了超重核294118和291116及其α衰变链上各核素的衰变势垒,采用量子力学中的WKB方法计算α衰变中的势垒穿透几率,对该链上各原子核的α衰变半衰期进行了研究。此外,还利用Royer公式对该链上各原子核的α衰变半衰期进行了计算。结果表明,GLDM考虑亲和能与Royer公式给出的α衰变半衰期与超重核区的实验值符合很好,验证了GLDM和Royer公式在超重核区的适用性,可以用来预测超重核的半衰期。最后,预言了Z=118和116同位素链上各核素的半衰期,结果表明,在Z=118和116中存在α衰变长寿命同位素,这需要实验上的检验。

~(176,178)Os新低位激发态的识别

利用在束实验产生具有β+/EC衰变性质核素176,178Ir,分析了在束实验条件下获得的γ-γ符合数据,识别出了176Os的4条新能级和13条新γ跃迁、178Os的5条新能级和14条新γ跃迁。籍助氦喷嘴快速带传输系统,进一步对176Ir的β+/EC衰变进行了测量,在确认在束测量新γ射线的同时建议了176Ir的一个低自旋同核异能态。通过两准粒子耦合的半经验计算,建议了176,178Ir基态及同核异能态的组态。

形变双奇核~(178)Ir转动带能级的旋称反转

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．

beta(+)/EC decay and systematic analysis of Ir-176,Ir-178

The gamma rays following the beta(+)/EC decay of Ir-176,Ir-178 nuclei have been investigated using in-beam gamma-ray experiment. In addition, with the aid of a helium-jet recoil fast tape transport system, the beta(+)/EC decay of Ir-176 was further studied, the new gamma rays were proved and a low-spin isomer was proposed in Ir-176. The isomeric state was analysized according to the systematics in neighboring nuclei.