缺中子~(176)Ir核β~+／EC衰变研究

在210MeV的束流能量下,利用重离子熔合蒸发反应146Nd(35Cl,5nγ)176Ir产生具有β+／EC衰变性质的核素176Ir,由氦喷嘴快速带传输系统将反应产物传送到低本底区进行测量．经过实验数据的离线处理分析,对早先发表的176Ir衰变γ跃迁进行确认的同时又发现了3个新能级和10条新的γ射线, 丰富了176Os核的低位激发态能级纲图．并根据典型γ射线的衰变时间谱建议了176Ir核的一个长寿命的低自旋同核异能态．

形变双奇核~(180)Ir的高自旋态实验研究

利用15 4 Sm( 31P ,5nγ) 180 Ir反应产生并研究了双奇核180 Ir的高自旋态 .实验中进行了180 Ir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180 Ir由 5个转动带构成的能级纲图 .依据从实验数据中提取出的带内B(M1 ) /B(E2 )值与理论计算值的比较 ,以及相邻双奇核的带结构特征 ,给出了转动带的准粒子组态 .在推转壳模型的理论框架中 ,定性地讨论了转动带结构特征的组态依赖性

双奇核~(176)Ir转动带的旋称反转(英文)

利用1 4 9Sm( 31 P ,4nγ)反应 ,通过γ射线的激发函数测量、X γ和γ γ符合测量研究了双奇核1 76Ir的高自旋态 .首次建立了双奇核1 76Ir由 4个转动带构成的能级纲图 .依据从实验数据中提取出的带内B(M1 ) B(E2 )值与理论计算值的比较 ,以及相邻双奇核的带结构特征 ,给出了转动带的准粒子组态 .基于本实验建立起的带间跃迁和在I=1 8处观测到的旋称交叉 ,指出1 76Ir核基于πh9 2 νi1 3 2 和πi1 3 2 νi1 3 2 组态的两个转动带在低自旋时出现旋称反转现象 .

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.

beta(+)/EC-decay study of Ir-176 neutron-deficient isotope

The beta(+)/EC decay of doubly odd Ir-176 has been investigated using Nd-146(Cl-35, 5n gamma)Ir-176 heavy ion fusion evaporation reaction at 210MeV bombarding energy. With the aid of a helium-jet recoil fast tape transport system, the reaction products were transported to a low-background location for measurements. Based on the data analysis, the previously published gamma rays in Ir-176 decay were proved, moreover, 3 new levels and 10 new gamma rays were assigned to Ir-176 decay. The new level scheme of Os-176 with low excitation energy has been established. The time spectra of typical gamma rays clearly indicate a long-lived low-spin isomer in Ir-176 nuclide.

Observation of a Possible New Isomer in Ir-175

The neutron deficient nuclide Ir-175 was produced by irradiation of Nd-146 with 210 MeV Cl-35 via a fusion-evaporation reaction channel. The reaction products were transported to a low-background location using a helium-jet recoil fast-moving tape-transport system for measurement. The experimental devices and data analysis method are introduced. Based on the decay-curve fitting of the beta-delayed gamma ray from Ir-175, realized by the least-square method, a new long-lived isomeric state of Ir-175 is proposed and briefly discussed.

Adsorption and reaction of thiophene and H2S on Mo2C/Al2O3 catalyst studied by in situ FT-IR spectroscopy

The reactions of both thiophene and H2S onMo(2)C/Al2O3 catalyst have been studied by in situ FT-IR spectroscopy. CO adsorption was used to probe the surface sites of Mo2C/Al2O3 catalyst under the interaction and reaction of thiophene and H2S. When the fresh Mo2C/Al2O3 catalyst is treated with a thiophene/H-2 mixture above 473 K, hydrogenated species exhibiting IR bands in the regions 2800-3000 cm(-1) are produced on the surface, indicating that thiophene reacts with the fresh carbide catalyst at relatively low temperatures. IR spectra of adsorbed CO on fresh Mo2C/Al2O3 pretreated by thiophene/H-2 at different temperatures clearly reveal the gradual sulfidation of the carbide catalyst at temperatures higher than 473 K, while H2S/H-2 can sulfide the Mo2C/Al2O3 catalyst surface readily at room temperature (RT). The sulfidation of the carbide surface by the reaction with thiophene or H2S maybe the major cause of the deactivation of carbide catalysts in hydrotreating reactions. The surface of the sulfided carbide catalyst can be only partially regenerated by a recarburization using CH4/H-2 at 1033 K. When the catalyst is first oxidized and then recarburized, the carbide surface can be completely reproduced.