水热-溶胶-凝胶法合成多壁碳纳米管-Na3V2（PO4）3复合物及其作为锂离子电池正极材料的性能

采用水热和溶胶-凝胶相结合的方法,制备了具有良好电化学性能的新型多壁碳纳米管-Na₃V₂（PO₄）₃（MWCNT-NVP）复合材料（MWCNT的质量分数为8.74%）. 通过场发射扫描电子显微镜表征可知,MWCNT分散在NVP纳米颗粒之间,并起到“电子导电线”的作用. 与纯Na₃V₂（PO₄）₃相比,MWCNT-NVP具有更高的比容量和更优异的循环性能. 在0.2C（35.2 mA·g^-1）的电流密度下,3.0-4.5 V的电压范围内,MWCNT-NVP的初始比容量为82.2 mAh·g^-1. 循环100次以后,比容量为72.3 mAh·g^-1. 在1.0-3.0 V充放电时,MWCNT-NVP的初始容量为100.6 mAh·g^-1. 100次循环以后,其容量保持率高达90%. 同时,交流阻抗测试表明,由于MWCNT的存在,MWCNT-NVP的导电性有了显著的提高. 以上结果表明,MWCNT-NVP是一种良好的锂离子电池电极材料.     

Pt/TiO2-Al2O3整体式催化剂的制备及甲醛废气催化氧化

以Al₂O₃-TiO₂混合物为载体,采用过量浸渍法负载Pt制备出催化剂涂层,再将其涂覆到堇青石蜂窝载体上制备了整体式催化剂,利用N₂吸附/脱附、XRD、NH₃-TPD、SEM-EDS表征。研究了催化剂涂层中TiO₂含量和Pt负载量对甲醛去除率的影响。结果表明：TiO₂的含量为5wt%,Pt的负载量为1wt%的整体式催化剂在室温（5~35 ℃）、甲醛气体进口浓度为50~300 mg·m^-3和体积空速为10000 h^-1的条件下,甲醛去除率达98.4%以上。连续反应150 h之后催化剂仍可保持良好催化活性。      

用TDMA法计算谐振子在强激光脉冲下的高次谐波

用含时薛定谔方程的多态展开(TDMA)方法求解含时薛定谔方程。该方法将含时波函数以基函数展开，通过求解展开系数的一阶微分方程组得到任意时刻的波函数。并将这一方法用于强激光场中谐振子的高次谐波的计算，以HCl分子为例，计算了在脉冲激光作用下高次谐波的产生和对应的激光强度、波长和脉冲宽度。     

40J激光装置研制

 报道了一台输出能量在40J量级的激光装置。该装置从星光Ⅱ激光装置分光作为光源,由放大器链、能源系统和支撑桁架等三大部分构成。对整个激光装置的模拟计算结果表明：装置的增益能力足够输出40J,B积分满足ΔB小于1.8的要求。研制了一种全腔水冷新型放大器,对其小信号增益系数和增益均匀性进行了测量,实验得出增益系数β为0.034cm ^-1,增益均匀性为91.84%。结果表明这种放大器完全能满足此激光装置的设计要求。     

利用1 064 nm激光预处理提高pickoff镜损伤阈值

 激光预处理是提高光学元件损伤阈值的有效方法之一。利用输出1 064 nm基频激光的SAGA激光器，采用光栅刻线式扫描的方式对镀多层高反物理膜的pickoff镜进行了能量周期递增的预处理，验证激光预处理对其损伤阈值的提高效果。结果表明：零几率损伤阈值平均提高38.8%，而50%几率损伤阈值提高了7.6%，经过激光预处理后pickoff镜抗损伤能力较处理前有了一定提高。     

Structure Characterization of HSQ Films for Low Dielectrics Using D5 as Sacrificial Porous Materials

Low-density materials, commercially available hydrogensilsesquioxane （HSQ） offer a low dielectric constant. HSQ films can be obtained by spin on deposition （SOD）. In this work, low-dielectric-constant HSQ films are prepared by using D5 （decamethylcyclopentasiloxane） as sacrificiaJ porous materials. The dielectric constant of silica films significantly changes from 3.0 to 2.4. We report the structural aspects of the films in relation to their composition after annealed at 300℃, 400℃, and 500℃ for 1.5h in nitrogen ambient and annealed at 400℃ for 1.5h in vacuum. Si-OH appears after annealed at 400℃ for 1.5h in vacuum. The results indicate that the proper condition is in nitrogen ambient. Intensity of the Sill peak increases with the increasing temperature. Fourier transform infrared spectroscopy is used to identify the network structure and cage structure of Si-O-Si bonds and other possible bonds. Dielectric constant k is significantly lowered by annealing at 350℃ for 1.5h in nitrogen ambient. The I-V and C-V measurements are used to determine the dielectric constant, the electric resistivity and the breakdown electric field.     

地面目标红外特性及其隐身技术研究

随着红外搜索与制导技术的飞速发展,对于地面目标红外特征及其隐身技术的研究具有越来越重要的军事意义.在简化目标传热模型的基础之上,计算出目标的瞬时温度变化,并与背景的温度比较发现,目标与背景在一天之中均存在明显温差,最大温差可达10℃.从目标与背景的辐射对比度出发,分析了辐射对比度与目标表面发射率以及目标与背景温差的关系,发现了当目标与背景温差控制在±4℃之内时,采用固定发射率涂料可以使目标达到红外隐身的目的.     

二次风率对分级进风燃烧室内湍流燃烧与NOx生成的影响

本文在分级进风燃烧室的热态实验装置上,测量了燃烧室内湍流燃烧的温度场和组分浓度场,研究了分级进风的流量比率即二次风率对燃烧及NOx生成的影响.得到了四组不同二次风率下燃烧室内气体温度和O2、CO2、CO与NO浓度的分布.     

Strengthened Hyper-Raman Lines with the Coherent Superposition State

High-order harmonic generations from a one-dimensional Coulomb potential atom are calculated with the initial state prepared as a coherent superposition between its ground and first excited states. When the energy difference of the two states is small, we can choose proper laser pulse such that the first excited state can be excited only to other bound states instead of being ionized. We show that only the hyper-Raman lines are observable instead of the harmonics. The energy difference of the ground and the first excited state can be deduced from the highest peak of the hyper-Raman lines. We further show that the similar results can be obtained by using a combination of two laser pulses with different frequencies interacting with the atom initially at the ground state.