Al2O3载体的合成及孔径调变

综述了氧化铝前驱体的组成,氧化铝的类型及其作为载体的三种合成方法,探讨其制备影响因素和工艺;氧化铝载体的表面修饰和孔径调变的物理及化学方法、工艺;总结了氧化铝载体制备方法及展望氧化铝载体发展方向。     

高择优取向硅基含钾铌酸锶钡（K:SBN）薄膜的制备与性能

采用NbCl5作为先驱物，利用溶胶-凝胶法在Si(100)衬底上成功获得高度择优取向的铁电铌酸锶钡(SBN)薄膜.与用Nb(OC2H5)5作为先驱物的SBN薄膜相比，NbCl5配制的薄膜前驱溶液中含有一定数量的K离子.K离子的含量对SBN薄膜取向的影响存在一个最优值.二次离子质谱测试发现，K离子对SBN晶胞的溶入和对Si衬底的渗透能够同时使SBN晶胞和Si晶胞产生微小扭曲，从而起到调整薄膜与衬底的匹配关系，并最终促使SBN薄膜c轴高度择优取向的生长.测试了薄膜的光学特性. 关键词： 铌酸锶钡 溶胶-凝胶方法 择优取向     

Near Band-Edge and Mid-Gap Photoluminescence of a ZnO Thin Film Grown on a （001） silicon Substrate

A nominally undoped wurtzite ZnO thin film of highly c-axis orientation was successfully grown on (001) silicon by metal-organic chemical vapour deposition, and its photoluminescence was measured as a function of excitation intensity at room temperature. The ZnO sample exhibited a strong near band-edge (NBE) line at 379.48nm (3.267eV) and a weak broad green band around-510 nm (2.43eV), showing a linear and sublinear excitation dependence of the luminescence intensity, respectively. No discernible intensity dependence of lineshape and emission peak was found for the NBE line. On the other hand, the peak energy of the green luminescence was found to increase nearly logarithmically with the increasing excitation intensity. The above results clearly indicate that in the ZnO epilayer, the NBE line was due to an excitonic spontaneous emission, while the mid-gap green luminescence can be assigned to the tunnel-assisted donor-acceptor pair (DAP) radiative recombination.Moreover, we obtained an energy depth β-11.74 meV for the potential wells due to the fluctuating distribution of the unintentional impurities/defects responsible for the tunnel-assisted DAP emission.     

多环型半导体探测器的研制

为了改进低能次级束逆运动学核反应角分布的测量，研制了空心的多环型半导体探测器，用来取代沿用多年的X-Y位置灵敏型半导体探测器. 论述了多环型探测器的优越性，介绍了其制作过程和工艺，给出了已研制成功的十一环探测器的性能测试结果.     

大爆炸核合成相关的8Li(d,p)9Li反应截面测量

利用8Li次级束测量了质心系能量7.8 MeV2H(8Li, 9Li)1H反应的角分布，导出了8Li(d, p)9Li反应的天体物理S因子及9Li→8Li+n虚衰变的渐近归一化系数. We have measured the angular distribution of 2H(8Li,9Li)1H at Ecm= 7.8 MeV and deduced the astrophysical S factor of 8Li(d, p)9Li reaction as well as the Asymptotic Normalization Coefficient (ANC) for 9Li → 8Li+n virtual decay.     

浅谈中原文化对南宋江南社会生活的影响——以“建炎南渡”后杭州(临安)为例

两宋交替时期,中原人大规模随北宋王室渡江南迁,以北宋东京为代表的中原文化迅速南传,给江南地区的传统文化带来了一定的影响,突出体现在饮食文化、文娱活动、节日及城市管理等方面。本文结合历史文献,着重从以上几个方面分析了中原文化南传对江南文化生活的影响,进而表明了南宋政权在对中原文化的继承与发扬问题上仍起到积极作用的观点。     

Test of Determination of (p,γ) Astrophysical S-Factors Using the Asymptotic Normalization Coefficients from Neutron Transfer Reactions

The asymptotic normalization coefficients （ANCs） for the virtual decay ^17 O→^16 O＋n are derived from the angular distributions of the 16 O（d, p）^17O reaction leading to the ground and first excited states of ^17O, respectively, using the distorted wave Born approximation and the adiabatic wave approximation. The ANCs of ^17F are then extracted according to charge symmetry of mirror nuclei and used to calculate the astrophysical S-factors of ^16 O（p, γ）^17 F leading to the first two states of ^17 F. The present results are in good agreement with those from the direct measurement. This provides a test of this indirect method to determine direct astrophysical S-factors of （P, γ） reaction. In addition, the S-factors at zero energy for the direct captures to the ground and first excited states of ^17 F are presented, without the uncertainty associated with the extrapolation from higher energies in direct measurement.     

氯离子对介孔氧化铝质子导电性的影响

掺杂氯盐使介孔氧化铝导电率提高近一个数量级,将掺杂的介孔氧化铝浸渍在水中24h后的导电率仍为纯介孔氧化铝的3～6倍。红外光谱结果显示,氯掺杂改变了表面酸碱活性中心,导致质子更易在介孔氧化铝中发生迁移,从而提高导电性。     

Enhancement of β^＋-Decay Rate of ^22Na in Metal Pd at Low Temperature

Temperature dependence of nuclear decays in metallic environments is a controversial issue. We measured the temperature dependence of the β^＋-decay half-life of ^22Na implanted into the metal host of palladium. It is found that the β^＋-decay half-life of ^22Na in the metal Pd cooled to T = 15 K is shorter by 0.46（14）% than that at room temperature. The result is consistent in sign with, but dearly smaller than, the estimated one by the Debye model.     

共面微带传输线超短电脉冲传输特性

本文用快速傅里叶变换对LTGaAs衬底共面微带传输线光生超短电脉冲的时域传输特性进行了数值计算结果表明,THz以上高频范围的模式色散、LTGaAs衬底切伦科夫辐射衰减使超短电脉冲信号沿LTGaAs衬底共面微带传输线超传输时波形畸变,初始光生电脉冲越窄,则信号波形畸变越严重减簿衬底厚度可降低LTGaAs衬底共面微带传输线的模式色散和辐射衰减,有利于改善LTGaAs衬底共面微带传输线亚皮秒超短电脉冲的传输特性.