爆磁压缩装置经组合功率调节系统产生高电压的实验研究

 介绍了以爆磁压缩装置为脉冲功率能源,经变压器和爆炸金属丝断路开关组合功率调节系统,在电阻负载上产生高电压的实验研究。实验结果为：在100W 水电阻负载两端得到了约800kV的高电压脉冲,脉宽约100ns。此项工作拓宽了爆磁压缩装置的应用范围。     

碳纳米纤维负载钯催化剂的制备及其催化性能研究

通过静电纺丝和碳化技术,将聚丙烯腈制备成碳纳米纤维并用于负载钯催化剂.扫描电镜(SEM)表征结果显示,碳化过程虽使部分纤维融合,但纤维结构保持良好;透射电镜(TEM)图显示,碳化过程中Pd原子有一定程度地聚集,形成了直径约为15nm的颗粒.催化结果表明,该催化剂对碘代芳烃和丙烯酸酯的Heck偶联反应具有良好的催化活性,生成物反式肉硅酸酯的产率较高;该催化剂至少可以重复使用5次（保持催化活性不变）,显示出良好的稳定性.     

SI2-拟代数空间

在T0空间上引入了SI2-代数空间和SI2-拟代数空间的概念,讨论了它们的一些性质,证明了：(1)一个T0空间(X,τ)为SI2-代数的当且仅当(X,τSI2)为B-空间;(2)一个T0空间(X,τ)为SI2-拟代数的当且仅当(X,τSI2)为超紧基空间;(3)一个T0空间(X,τ)为SI2-代数的当且仅当(X,τ)为交SI2-连续和SI2-拟代数的。     

丁酮分子内价轨道1a″的电子动量谱学研究

用高分辨率电子动量谱仪进行丁酮分子的结合能谱和内价轨道1a″电子动量谱的实验工作，以及用Hartree-Fock和密度泛函理论方法对1a″轨道电子动量谱的理论研究. 得到了各价轨道的电离能值以及理论计算的总能、偶极矩和1a″轨道的二维密度图. 并比较了内价轨道1a″的电子动量谱的实验和理论计算结果，实验结果与理论计算符合较好.     

轴流式水轮机转轮流固耦合计算

在利用轴流式水轮机全流道三维非定常湍流数值计算和利用弹性力学非稳态有限元法计算轴流式水轮机转轮叶片动态的应力和应变的基础上,利用弱耦合算法完成了轴流式水轮机在有粘有旋条件下的流固耦合计算,得到了叶片的动态应力和动态应变,并对结果进行了讨论.     

BeH，BeD，BeT分子基态(X2Σ+)的结构与势能函数

采用量子力学从头算方法，运用二次组态相互作用QCISD(T)/aug-cc-pVTZ和电子相关单双耦合簇CCSD(T)/6-311++G(3df，2pd)研究了BeH，BeD，BeT分子基态的结构与势能函数，计算出了这些分子的光谱数据(ω_e，ω_eχ_e，B_e，α_e，D_e)，结果与实验光谱数据吻合较好.这表明上述分子基态的势能函数可用经修正的Murrell-Sorbie+c₆函数来表示. 关键词： BeH BeD BeT分子基态 分子结构 势能函数     

First-principles investigation on the elastic stability and thermodynamic properties of Ti2SC

Using Vanderbilt-type plane-wave ultrasoft pseudopotentials within the generalized gradient approximation（GGA） in the frame of density functional theory（DFT）,we have investigated the crystal structures,elastic,and thermodynamic properties for Ti2SC under high temperature and high pressure.The calculated pressure dependence of the lattice volume is in excellent agreement with the experimental results.The calculated structural parameter of the Ti atom experienced a subtle increase with applied pressures and the increase suspended under higher pressures.The elastic constants calculations demonstrated that the crystal lattice is still stable up to 200 GPa.Investigations on the elastic properties show that the c axis is stiffer than the a axis,which is consistent with the larger longitudinal elastic constants（C 33,C 11） relative to transverse ones（C 44,C 12,C 13）.Study on Poisson＇s ratio confirmed that the higher ionic or weaker covalent contribution in intra-atomic bonding for Ti2SC should be assumed and the nature of ionic increased with pressure.The ratio（B/G） of bulk（B） and shear（G） moduli as well as B/C 44 demonstrated the brittleness of Ti2SC at ambient conditions and the brittleness decreased with pressure.Moreover,the isothermal and adiabatic bulk moduli displayed opposite temperature dependence under different pressures.Again,we observed that the Debye temperature and Gru篓neisen parameter show weak temperature dependence relative to the thermal expansion coefficient,entropy,and heat capacity,from which the pressure effects are clearly seen.     

含有源频率选择表面可调复合吸波体

基于传输线等效理论,设计了含有源频率选择表面(active frequency selective surface,AFSS)的三层可调复合吸波体,第一层是表面层,为AFSS衬底;中间层是AFSS层,由频率选择表面(frequency selective surface,FSS)和PIN二极管阵列构成;第三层是介质层.反射率测量结果表明,通过调节PIN二极管阵列偏置电压可以动态调节吸波体反射特性,在偏置电压为5 V时,可获得最佳吸波性能,在5—15 GHz和5.3—13 GHz频段分别可获得-8 dB和- 关键词： 频率选择表面 复合吸波材料 反射率 PIN二极管     

Influence of annealing treatment on as-grown Ib-type diamond crystal at a high temperature and high pressure

In this paper,we report on the influence of annealing treatment on as-grown Ib-type diamond crystal under high pressure and high temperature in a china-type cubic anvil high-pressure apparatus.Experiments are carried out at a pressure of 7.0 GPa and temperatures ranging from 1700 C to 1900 C for 1 h.Annealing treatment of the diamond crystal shows that the aggregation rate constant of nitrogen atoms in the as-grown Ib-type diamond crystal strongly depends on diamond morphology and annealing temperature.The aggregation rate constant of nitrogen remarkably increases with the increase of annealing temperature and its value in octahedral diamond is much higher than that in cubic diamond annealed at the same temperature.The colour of octahedral diamond crystal is obviously reduced from yellow to nearly colorless after annealing treatment for 1 h at 1900 C,which is induced by nitrogen aggregation in a diamond lattice.The extent of nitrogen aggregation in an annealed diamond could approach approximately 98% indicated from the infrared absorption spectra.The micro-Raman spectrum reveals that the annealing treatment can improve the crystalline quality of Ib-type diamond characterized by a half width at full maximum at first order Raman peak,and therefore the annealed diamond crystals exhibit nearly the same properties as the natural IaA-type diamond stones of high quality in the Raman measurements.     

Higgs and Bottom Quarks Associated Production at High Energy Colliders in the Littlest Higgs Model with T-Parity

In the littlest Higgs Model with T-parity,we discuss the Higgs production in association with bottom quarks at the LHC and future electron-positron collider.We calculate the cross sections of production channels pp→bb H,bb→H and bg→b H at 14 Te V LHC and the cross sections of production channel e~+e~-→bb H in(un)polarized beams at the lowest order.In order to investigate the observability,we display some typical final state distributions in the Higgs to diphoton channel.