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101.
102.
CHEN Yong-Jing ZHU Sheng-Jiang CHE Xin-Lai DING Huai-Bo LI Ming-Liang 《中国物理C(英文版)》2006,30(8):740-744
High-spin structures in 146Ce nucleus have been re-investigated by measuring the prompt γ rays from spontaneous fission of 252Cf. The previously reported level scheme of 146Ce has been updated. The octupole deformed collective bands have been extended up to higher spin states. A possible quasi-γ band structure was examined and reconstructed according to our data analysis. In addition, the reflection asymmetric shell model was applied to describe the octupole deformed bands in 146Ce, and the calculated results are in good agreement with the experimental data at lower spins. 相似文献
103.
ZHU Sheng-Jiang XIAO Shu-Dong CHE Xing-Lai YU Ying-Nan LI Ming-Liang CHEN Yong-Jing ZHU Li-Hua WEN Shu-Xian WU Xiao-Guang LI Guang-Sheng 《中国物理C(英文版)》2005,29(11):1047-1051
Using heavy-ion nuclear reaction and in-beam γ-ray spectroscopy technique,high spin states of 136La have been studied. The nuclear reaction used is 130Te(11B,5n) with a beam energy 60MeV. The level scheme with three collective band structures has been updated with spin up to 20h. The collective backbending has been observed in $\uppi h_{11/2}\otimes \upnu h_{11/2}$ band. According to the TRS calculations,this backbending is due to the alignment of a pair of h11/2 neutrons. The signature splitting and inversion for the $\uppi h_{11/2}\otimes \upnu h_{11/2}$ band were also discussed. Other two bands based on $12^-$ and $16^+$ levels were proposed as oblate deformation with $\gamma\approx -60^\circ$. They most probably originate from four- and six- quasiparticle configurations, that is,$\uppi h_{11/2}\otimes\upnu g_{7/2} h_{11/2}^2$ and $\uppi g_{7/2}\otimes\upnu g_{7/2}^2 d_{5/2}h_{11/2}^2$ respectively. 相似文献
104.
线阵CCD的调制传递函数 总被引:7,自引:3,他引:4
线阵CD作为成像器件得到了日益广泛的应用,因而研究线阵CCD的调制传递函数MTF显得非常必要和重要。本文分析线阵CCD动态MTF及静态MTF,并对其影响因素进行讨论。 相似文献
105.
Reaction of 8-hydroxyquinoline (HQ) with Pb(NO3)2 in water resulted in the formation of a tetranuclear complex [Pb4(HQ)6(NO3)2] 1. It has been characterized by IR, elemental analyses and X-ray diffraction. Crystal data for this complex: triclinic system, space group P1, a = 9.7399(6), b = 11.6535(8), c = 12.6806(8) A, α = 62.8050(10), β = 78.4910(10), γ = 80.5490(10)°, C54H36N8O12Pb4, Mr= 1817.67, Z = 1, V = 1250.04(14)A^3, Dc = 2.415 g/cm^3,μ = 13.503 mm^-1, -12≤h≤8, -14≤k≤13, -15≤1≤15, F(000) = 840, Rint = 0.0217, R= 0.0348 and wR = 0.0927. X-ray crystal structure analysis revealed that in 1 each Pb( II ) contains a stereo- chemically active lone pair of electrons. The Pb…C interaction, C-H……O weak interaction and π…π stacking interactions are observed in the complex. In the solid state, the complex possesses strong photoluminescent emission at 485 and 528 nm. 相似文献
106.
107.
Amid five tastes, only salt is indispensable. As a kind of essential nutrition, salt plays a vital role in our daily life. Although the salt is in small particle size, yet it received a lot of rumors. In recent years, rumors on salt have sprung like mushrooms including sea salt, iodized salt, low sodium salt, additive in salt and so on. To stop the rumors from spreading and to clarify that the salt is innocent, a debate competition was applied to tell the truth:rumors are guilty rather than salt! 相似文献
108.
本文用粉末烧结法合成了Tl-Ba-Ca-Cu-O体系TlBa2Can-1CunO2n+2.5新系列超导相,用粉末衍射法测定了n=2和3的晶体结构,属简单四方单胞,空间群为D4h1-P4/mmm,点阵常数a相同,而c值不同,随n值而增大。a=3.847?,c分别为12.73?和15.89?,每单胞含一个化合式单位,阳离子沿四方晶系的(0,0,z)和(1/2,1/2,z)位置交替排列,排列的顺序相同,n=3比n=2依次多增加Ca和Cu及相应的氧离子。TlBa2CanCunO2n+2.5,n=3时,零电阻超导转变温度Tc(0)=112K;n=2时,Tc(0)=101K,与Tl2Ba2Can-1CunO2n+4型体心四方晶胞超导相不同,TlBa2Can-1CanO2n+2.5结构中缺氧类钙钛矿型结构单元[Ba2Can-1CunO2n+1]仅被TI-O单层所隔开,当n相同时,Tl-O双隔层的体心四方单胞比Tl-O单层的简单四方单胞的超导转变温度高10K左右,这说明Tl-Ba-Ca-Cu-O体系中超导相的转变温度不仅与类钙钛矿结构单元的[CuO4]和[CuO5]的数目有关,而且与Tl-O的隔层数目有关。
关键词: 相似文献
109.
用INDO/CT方法研究了C60分子的电子结构及基态和激发态光谱(S0→Sn,S1→Sn,T1→Tn),激发态分子动态学和反饱和吸收的微观机制,用动态模型解速率方程,实现反饱和吸收的必要条件是激发态对激光的吸收截面,在波长532nm的激光作用下,C60满足该条件,故C60呈现反饱合吸收特征,理论分析与实验结果一致。 相似文献
110.
在线毛细管柱SFC/FTIR联用方法 总被引:3,自引:0,他引:3
建立了一种以CO_2为流动相的毛细管柱SFC/FTIR联用方法,实现了对多环芳烃混合物和催眠药混合物的分离。其在线红外光谱图具有高信噪比,可直接用于混合物组分定性分析。该法对甲基丙烯酸甲酯的v_(c—o)带和对萘的v_(c—c)带的检测限分别为25ng和102ng。 相似文献