High-K multi-particle bands and pairing reduction in 254No

The multi-particle states and rotational properties of the two-particle bands in 254No are investigated by the cranked shell model with pairing correlations treated by the particle number conserving method.The rotational bands on top of the two-particle K^π=3^+,8^− and 10^+ states and the pairing reduction are studied theoretically in 254No for the first time.The experimental excitation energies and moments of inertia of the multi-particle states are reproduced well by the calculations.Better agreement with the data is achieved by including the high-order deformation ε6,which leads to enlarged Z=100 and N=152 deformed shell gaps.An increase of J¹ in these two-particle bands compared with the ground state band is attributed to the pairing reduction due to the Pauli blocking effect.     

静水压下加筋圆柱壳振动特性样条分析方法

本文用样条方法[1]分析了静水压下纵向加筋和环向加肋圆柱壳体的振动特性,文中导出的样条步长矩阵,将等步长样条推广为变步长样条,拓广了样条的使用。文中探讨了静水压对加筋圆柱壳振动特性的影响以及不同加筋对振动特性的影响,计算了几个模型,并与其它文献计算结果进行了比较。     

Production rates of cosmogenic nuclei on the lunar surface

A physical model for Geant4-based simulation of the galactic cosmic ray (GCR) particles' interaction with the lunar surface matter has been developed to investigate the production rates of cosmogenic nuclei. In this model the GCRs, mainly very high energy protons and α particles, bombard the surface of the Moon and produce many secondary particles, such as protons and neutrons. The energies of protons and neutrons at different depths are recorded and saved as ROOT files, and the analytical expressions for the differential proton and neutron fluxes are obtained through the best-fit procedure using ROOT software. To test the validity of this model, we calculate the production rates of the long-lived nuclei ¹⁰Be and ²⁶Al in the Apollo 15 long drill core by combining the above differential fluxes and the newly evaluated spallation reaction cross sections. Our numerical results show that the theoretical production rates agree quite well with the measured data, which means that this model works well. Therefore, it can be expected that this model can be used to investigate the cosmogenic nuclei in future lunar samples returned by the Chinese lunar exploration program and can be extended to study other objects, such as meteorites and the Earth's atmosphere.     

中重核基态α转移率的理论研究

本文利用简化的j-j耦合双能级成对力模型,得到了中重核基态α转移率的解析表达式.结果表明,类似于对转移,单个不成对核对α转移有阻塞效应,这与已有的实验事实一致.     

微聚焦管硬x射线位相衬度成像

利用微聚焦管硬x射线光源进行同轴位相衬度成像实验，所用的光源聚焦尺寸最小可达0.5μm.根据微聚焦硬x射线管的光学传递函数，对光源尺寸、相干长度等因素对成像分辨率的影响进行了分析.对新鲜的未经任何处理的生物样品进行了位相衬度成像，分辨率在10μm左右，并和吸收衬度成像进行了对比.实验结果表明利用微聚焦管作为硬x射线光源，多色硬x射线位相衬度成像可以得到比吸收衬度成像高得多的分辨率. 关键词： 位相衬度成像 微聚焦管x射线源 吸收衬度成像 光学传递函数     

反三角函数和三角方程

程是 一、选择题: 1.适合arccosx>.了万的:值的集合是()。 (A)哎x 10成:相似文献   

中子晕核结构在引起核碎裂中的特殊作用

基于同位旋相关量子分子动力学模型，研究和对比分析了中子晕核¹¹Li和相等质量稳定核¹¹B在相同入射道条件下引起核碎裂反应中的特征. 由于中子晕核松散的晕中子结构和小的分离能与相等质量稳定核相比具有容易碎裂的特征，因此在较低能区这种松散的晕结构有利于碎裂过程的发生，随入射能量升高，这种晕结构效应逐渐消失. 而且这种在碎裂中的中子晕结构作用随靶核质量和碰撞参数的增加而减弱.     

1-[4-(二甲氨基)苯亚甲基氨基]-4-苯基硫脲的另一个手性对映体晶体结构

对-二甲氨基苯甲醛和苯基氨基硫脲缩合反应生成1-[4-(二甲氨基)苯亚甲基氨基]-4-苯基硫脲(DMB), 产物能从溶液中析出单一手性对映体晶体. 用单晶X射线衍射技术测定了它的绝对构型, 晶体属正交晶系, P2₁2₁2₁空间群, a＝0.7870(2) nm, b＝1.1560(2) nm, c＝1.6668(3) nm, V＝1.5164(5) nm³, Z＝4, D_c＝1.307 g/cm³, F(000)＝632, μ＝0.213 mm^－1, 2557个可观测点[I＞2s(I)]精修的最终残差因子: R＝0.0409, wR＝0.1061, Flack参数为0.00(9), 能够确定绝对构型. 化合物的晶体结构和大宗粉末样品的固体圆二色谱表明化合物在结晶过程中发生单一对映体的手性堆积.     

含有十核羧酸一水杂化簇合物的二维铜配位聚合物的构筑

以新生的氢氧化铜、2,2’-二苯基二羧酸（H2bpda）以及柔性配体l,3二（4．吡啶）丙烷（bpp）N原料,超声反应条件下,在甲醇．水混合溶剂中合成了1个新型配合物,{[cu2（bpp）2（H20）2（bpda）2]．6H2O}。（1）,并对该配合物进行了元素分析、红外光谱分析、热重分析、脱水／重新吸水分析以及晶体结构研究X射线单晶结构分析表明,配合物1中含有一种由类似椅式构象的六核水簇及两个水分子所组成的八核水簇．该八核水簇结构类似环脂烃（1r,4r）二甲基-环己烷,显示出水分子簇与有机分子结构上的相似性．有趣的是,该八核水簇与周围羧酸根中的氧原子通过氢键作用形成了类似于（H2O）10纯水簇的十核羧酸一水杂化簇合物．此外,该配合物具有可逆的脱水／重新吸水性能．