基于摄动法分析重力坝损伤的概率密度演化过程

提出了一种对重力坝进行损伤概率演化过程分析的方法.首先,使用虚拟激励法和Mazars损伤模型分析了初始迭代过程中,在坝体在确定性静力荷载和随机的地震荷载激励下的重力坝损伤因子期望值与方差的计算;然后基于摄动法分析了在其余迭代过程中,重力坝损伤因子的概率密度演化过程.最后,给出了实例分析,并分析了坝体的损伤分布情况以及本文方法的收敛性与稳定性.     

垂直管内蒸汽射流凝结流型研究

本文实验研究了垂直管内蒸汽射流凝结流型,通过安装在管道壁面的高频压力传感器获取蒸汽在流动水中凝结诱导形成的压力波动信号,统计提取能清晰表征不同蒸汽射流凝结流型的压力振荡特征。基于不同蒸汽射流凝结流动工况下压力信号的绝对值方差变化规律,对不稳定间歇振荡、不稳定界面振荡、不稳定气泡振荡/稳定凝结流型进行划分。再根据不稳定气泡振荡凝结流型所对应压力振荡信号的绝对值方差明显大于稳定凝结流型,将不稳定气泡振荡凝结流型从不稳定气泡振荡/稳定凝结流型中区分。通过本文建立的管内蒸汽射流凝结流型图,可以应用低系统压力下的流型变化来预测较高系统压力下的流型分布。     

免疫亲和色谱特异性剔除中药方剂四逆散中的柚皮苷

为了获得剔除柚皮苷(naringin)的中药方剂四逆散样品以供其药理活性探讨时使用,制备了抗柚皮苷抗体的免疫亲和色谱柱,用于特异性地剔除四逆散中的柚皮苷。首先合成了柚皮苷的完全抗原柚皮苷与牛血清白蛋白的结合物naringin-BSA,并用naringin-BSA对新西兰兔进行免疫获得抗血清,再将其纯化后与经CNBr活化的Sepharose 4B凝胶共价偶联制成免疫亲和色谱柱。将四逆散提取物样品溶液上样该色谱柱,洗脱,制得特异性剔除了柚皮苷的四逆散样品。由检测结果可知,naringin-BSA被成功合成。将其用于免疫新西兰兔,获得的抗血清的效价经酶联免疫吸附法（ELISA）测定达到1∶30000,抗体IgG的纯度达94%,交叉反应率低。在IgG与Sepharose 4B合成的IgG-Sepharose免疫亲和色谱柱中,IgG的偶联率为87%。用该免疫亲和色谱柱处理四逆散后,其中所含的柚皮苷几乎完全被剔除。结果证明,利用抗柚皮苷免疫亲和色谱,能特异性地剔除四逆散或其他样品中的柚皮苷成分。     

糖酵解模型差速流动引起的不稳定性和时空结构

建立了糖酵解模型(Selkov模型)差速流动型反应扩散方程,理论研究了均匀定态的稳定性,结果表明,当自催化物B的流速大于临界值c时,系统存在运流不稳定性(Convective instability);数值模拟分别得到了B在不同时刻和不同流速下的时空结构,显示了一些特殊性质,同时也证实了运流不稳定性的存在。     

High-spin states in neutron-rich ~(102)Mo nucleus

High-spin states in neutron-rich 102Mo nucleus have been studied by measuring the prompt γ-rays in the spontaneous fission of 252Cf. The previous level scheme has been updated and some new levels and transitions are identified. The one-phonon γ-band is expanded and a band head level of the two-phonon γ- band is proposed. The systematic characteristics of yrast bands, one-phonon γ-bands, two-phonon γ-bands and quasi-particle bands in 102Mo, 104Mo and 106Mo are discussed.     

垂直管内音速蒸汽射流凝结汽羽形状研究

本文针对质量流量376～773 kg·m^-2·s^-1的饱和蒸汽在温度变化范围为10～55℃流动水中形成的音速蒸汽射流凝结进行了实验研究。实验观察到了四种不同的汽羽形状,并且汽羽形状受Re影响较大。当Re与凝结驱动势减小时,最大膨胀比和汽羽喷射长度增大,其值小于蒸汽音速射流在静止水中的情况。本文给出了汽羽喷射长度实验关联式,大多数实验数据与预测值的误差小于10%。     

Proposed Chiral Doublet Bands in ^98Tc

High spin states in odd-odd ^98 Tc nuclei are studied by in-beam γ-ray spectroscopy with the ^96 Zr（^6Li, 412） fusionevaporation reaction at a beam energy of 35MeV. The previous level scheme is updated. A band based on 1090.7keV is expanded, and another band based on 1920.6 keV is newly identified. The observed two negative parity bands in ^98 Tc are proposed to be a pair of chiral doublet bands with the configuration πg9/2 vh11/2. The evidence supporting the assignment of the chiral doublet bands is discussed. Signature splitting and signature inversion are observed in the πg9/2 vh11/2 band in ^98Tc.     

Some progress in research on octupole deformation around Z=56, N=88 nuclei

Recent progress in research on octupole deformation around Z=56, N=88 neutron-rich nuclei by our cooperative groups of Tsinghua University, Vanderbilt University and Lawrence Berkeley National Laboratory has been introduced. The experiment was carried out by measuring the prompt γ-rays in spontaneous fission of ²⁵²Cf with the Gammasphere detector array. The new results of