高压烧结制备Tb掺杂n型(Bi1–xTbx)2(Te0.9Se0.1)3合金及其微结构和热电性能

采用高压烧结技术制备了稀土元素Tb掺杂的n型Bi2Te2.7Se0.3基纳米晶块体热电材料.将高压烧结成型的样品于633 K真空退火36 h.研究了Tb掺杂量对样品的晶体结构和热电性能的影响.结果表明,高压烧结制备的样品为纳米结构, Tb掺杂使样品的晶胞体积变大,功率因子增大,热导率降低,从而使ZT值提高.Tb掺杂量为x=0.004是最优的掺杂量,该掺杂量的高压烧结样品经退火处理后,于373 K时ZT值达到最大为0.99,并且在323-473 K范围内, ZT值均大于0.8,这对用于温差发电领域具有重要意义.     

超空泡射弹水下侵彻靶板三相耦合数值模拟

超空泡射弹侵彻问题的实质是特殊水下结构受到高速冲击载荷作用下的动态响应。对12.7 mm口径超空泡射弹侵彻典型水下目标壳体的毁伤效果开展研究,基于LS-DYNA有限元分析软件建立水环境中超空泡射弹垂直侵彻曲面靶板的等效模型,探讨射弹侵彻过程中动能侵彻和气泡溃灭对靶板联合毁伤效果,获得了靶板在各阶段的应力变化和结构变形规律。结果表明:侵彻靶板前,射弹着靶速度为200 m/s时的头部表面水介质压力峰值达768 N,靶板表面有明显下凹变形;侵彻靶板时,伴随着射弹动能侵彻和气泡溃灭冲击,水介质造成的影响不足动能侵彻的2%;侵彻靶板后,在靶板正面形成峰值速度为42 m/s的水射流进一步作用于破口;靶板整体弯曲变形,在200~300 m/s范围内,随着射弹着靶速度的增加,靶板弯曲形变量减小;靶板局部发生延性穿孔,射弹在水环境中具有更好的破口效果,射弹速度变化对破口尺寸影响不大。     

激光雷达辅助驾驶道路参数计算方法研究

针对特定场景辅助驾驶的需求,构建道路场景车载激光雷达三维扫描系统,并设计基于三维激光点云的道路参数提取与计算方法,包括路面宽度、横杆或桥梁或隧道限高、拐弯半径等等,为辅助判断道路的可通过性提供决策依据。测试和对比实验表明,所设计算法效果稳定、精度良好,在效率和自动化程度上有一定优势,可为辅助驾驶提供非常有益的决策参数。     

Soliton molecules and the CRE method in the extended mKdV equation

The soliton molecules of the(1+1)-dimensional extended modified Korteweg–de Vries(mKdV)system are obtained by a new resonance condition, which is called velocity resonance. One soliton molecule and interaction between a soliton molecule and one-soliton are displayed by selecting suitable parameters. The soliton molecules including the bright and bright soliton, the dark and bright soliton, and the dark and dark soliton are exhibited in figures 1–3, respectively.Meanwhile, the nonlocal symmetry of the extended mKdV equation is derived by the truncated Painlevé method. The consistent Riccati expansion(CRE) method is applied to the extended mKdV equation. It demonstrates that the extended mKdV equation is a CRE solvable system. A nonauto-B?cklund theorem and interaction between one-soliton and cnoidal waves are generated by the CRE method.     

基于广义逆矩阵的Bézier曲线近似合并

Bézier曲线近似合并算法在几何数据压缩方面有着重要的应用.研究了两条相邻Bézier曲线近似合并的问题,用矩阵的形式给出了相邻Bézier曲线可精确合并的条件,并在此基础上通过广义逆矩阵的方法求解合并逼近后的Bézier曲线.同时,对保端点插值条件的近似合并也给出了结果.最后用实例说明了算法的有效性,得到了很好的逼近效果.     

显微动态图像分析技术及其在生物物理中的应用

介绍了一种可实时监测细胞生命活动的显微动态图像分析技术。该技术把显微光学成像技术、数字处理技术和动态图像分析技术结合为一体,可实现对活细胞的结构功能、生长过程和环境变化的影响等进行非侵入性连续监测。通过在细胞膜弹性模量测量中的应用表明,该技术不仅原理可靠,实现容易,应用方便,而且检测速度快,测量精度高,稳定性能好。此项技术可望在生物物理学的实验研究中获得广泛的应用。     

铝粉点火微观机理的光谱研究

 铝粉是一种含能高的材料,它被广泛地添加到含能材料中。利用3台单色谱仪和OMA谱仪等多种谱仪技术,研究了铝粉在几种不同环境下的快速反应微观特性。研究表明：铝粉冲击波点火的临界条件和铝粉的物理状态相关。微米铝粉点火的临界温度为2 100 K,它接近Al₂O₃的熔化温度。它表明,在空气中容易氧化的微米铝粉点火,必须使铝粉表面的氧化层熔化。在气相反应中,微米铝粉和氧的反应是主要的;和水的反应是次要的。减小微米铝粉的颗粒尺寸,可以明显提高快速反应温度。 含铝复合燃料中的液体燃料反应后的铝粉才能参与反应;铝粉添加至气相反应介质后将明显提高反应温度。     

19F+27Al耗散反应中双核系统的转动与形变

测量了¹⁹F+²⁷Al耗散反应产物B,C,N,O,F和Ne的激发函数,入射束流的能量从110.25MeV到118.75MeV, 能量步长为250keV. 从产物的 能量自关联函数中提取了反应中所形成的中间双核系统的转动惯量, 与相粘模型计算的刚体转动惯量相比较, 结果表明形成的双核系统有大的形变.     

Determination of Trace Mercury by Solid Substrate-Room Temperature Phosphorimetry Quenching Method Based on Catalytic Effect of Hg2+on Formation of the Ion Association Complex [Sn(XO)6]4+·[(Fin)4]

A new method for the determination of trace mercury by solid substrate-room temperature phosphorimetry (SS-RTP) quenching method has been established. In glycine-HCl buffer solution, xylenol orange (XO) can react with Sn⁴⁺ to form the complex [Sn(XO)₆]⁴⁺. [Sn(XO)₆]⁴⁺ can interact with Fin⁻ (fluorescein anion) to form the ion associate [Sn(XO)₆]⁴⁺·[(Fin)₄]⁻, which can emit strong and stable room temperature phosphorescence (RTP) on polyamide membrane (PAM). Hg²⁺ can catalyze H₂O₂ oxidizing the ion association complex [Sn(XO)₆]⁴⁺·[(Fin)₄]⁻, which causes the RTP to quench. The ΔIp value is directly proportional to the concentration of Hg²⁺ in the range of 0.016–1.6 fg spot⁻¹ (corresponding concentration: 0.040–4.0 pg ml⁻¹, 0.40 μl spot⁻¹), and the regression equation of working cure is ΔIp=10.03+83.15 m Hg²⁺ (fg spot⁻¹), (r=0.9987, n=6) and the detection limit (LD) is 3.6 ag spot⁻¹(corresponding concentration: 9.0×10^–15 g ml⁻¹, the sample volume: 0.4 μl). This simple, rapid, accurate method is of high selectivity and good repeatability, and it has been successfully applied to the determination of trace mercury in real samples. The reaction mechanism for catalyzing H₂O₂ oxidizing the ion association complex ([Sn(XO)₆]⁴⁺·[(Fin)₄]⁻) SS-RTP quenching method to determine trace mercury is also discussed.     

Sensitivity of depolarized lidar signals to cloud and aerosol particle properties

Measurements from depolarized lidars provide a promising method to retrieve both cloud and aerosol properties and a versatile complement to passive satellite-based sensors. For lidar observations of clouds and aerosols, multiple scattering plays an important role in the scattering process. Monte Carlo simulations are carried out to investigate the sensitivity of lidar backscattering depolarization to cloud and aerosol properties. Lidar parameters are chosen to be similar to those of the upcoming space-based CALIPSO lidar. Cases are considered that consist of a single cloud or aerosol layer, as well as a case in which cirrus clouds overlay different types of aerosols. It is demonstrated that besides thermodynamic cloud phase, the depolarized lidar signal may provide additional information on ice or aerosol particle shapes. However, our results show little sensitivity to ice or aerosol particle sizes. Additionally, for the case of multiple but overlapping layers involving both clouds and aerosols, the depolarized lidar contains information that can help identify the particle properties of each layer.