Li2O-TiO2-SiO2-P2O5和Li2O-TiO2-Al2O3-P2O5体系锂离子固体电解质的制备及性能研究

一些具有NASICON型网格结构的固体电解质具有高的电导率和好的稳定性,NASICON的意思是Na Super Ionic Conductor[1]。当NaZr2(PO4)3中P5 被Si4 部分取代时便可以得到具有NASICON结构的Na1 xZr2SixP3-xO12体系,其具有高的钠离子电导率。然而有相同结构的Li1 xZr2SixP3-xO12体系的离子电导率却很低,这是因为Li 半径太小,而NASICON三维网格结构的离子通道太大,两者不匹配而使电导率下降[2]。但当LiZr2(PO4)3中Zr4 被离子半径小些的Ti4 取代,所得LiTi2(PO4)3的通道就与Li 半径相匹配,适合于锂离子的迁移,从而使其电导率…     

C60与硅烯环加成反应机理的理论研究

用半经验AM1法研究了C     

取样窗口迹长均值估计方法的讨论

采用窗口取样法测量岩体中随机不连续面的迹长, 相对于无限二维空间的岩体而言存在着不可避免的偏差。因此, 在实际岩体工程中要对实地测量迹长的偏差进行校正, 以获得校正后的平均迹长。本文着重讨论了Kulatilake教授于 1984年提出的不连续面迹长均值估算法, 并对算法作了必要的修正, 使算法更客观, 更完善, 编制的计算机代码可以很方便地求取无限二维岩体不连续面的校正迹长。     

多维广义SRLW方程的Chebyshev拟谱方法分析

考虑了一类多维的广义对称正则长波(SRLW)方程的齐次初边值问题Chebyshev拟谱逼近,构造了全离散的Chebyshev拟谱格式,给出了这种格式近似解的收敛性和最优误差估计。     

Analysis of multiple interfacial cracks in three-dimensional bimaterials using hypersingular integro-differential equation method

By using the concept of finite-part integral, a set of hypersingular integro-differential equations for multiple interracial cracks in a three-dimensional infinite bimaterial subjected to arbitrary loads is derived. In the numerical analysis, unknown displacement discontinuities are approximated with the products of the fundamental density functions and power series. The fundamental functions are chosen to express a two-dimensional interface crack rigorously. As illustrative examples, the stress intensity factors for two rectangular interface cracks are calculated for various spacing, crack shape and elastic constants. It is shown that the stress intensity factors decrease with the crack spacing.     

脉冲相干激光雷达的散斑成像模型及其散斑噪声压缩

推导了脉冲相干激光雷达的散斑成像模型,证明了脉冲相干激光雷达图像中散斑噪声的乘法性质。根据其统计规律,提出一种新的用于散斑噪声压缩的并行加权均值多方向形态滤波算法。模拟结果表明此算法既有 地压缩了散斑噪声又保持了图像的几何结构,并且通过比较,证明其优于Safa的多方向形态滤波算法。     

一类非线性积分微分方程的整体解的存在性与非存在性

研究了一类非线性积分微分方程的初边值问题,证明了其整体解的存在性、惟一性和稳定性及在一定条件下,整体解的不存在性。     

酚醛玻璃钢动态本构关系的实验研究

本文叙述了在轻气炮上作高速撞击实验,使用碳膜压阻传感器,一次记录多个应力历史波形,用Lagrange分析和路径线方法,求材料动态本构关系的方法。给出了应力在2 GPa、应变率4105S-1以下酚醛玻璃钢的数值形式本构关系。探讨了强应力脉冲在酚醛玻璃钢中传播衰减的物理原因。     

Beam dynamics simulations of the injector for a compact THz source

Terahertz radiation has broad application prospects due to its ability to penetrate deep into many organic materials without the damage caused by ionizing radiations. A free electron laser （FEL）-based THz source is the best choice to produce high-power radiation. In this paper, a 14 MeV injector is introduced for generating high-quality beam for FEL, is composed of an EC-ITC RF gun, compensating coils and a travelling-wave structure. Beam dynamics simulations have been done with ASTRA code to verify the design and to optimize parameters. Simulations of the operating mode at 6 MeV have also been executed.