煤岩钻孔水射流自旋转喷头限速研究

采用理论推导结合实验的方法,首先借鉴发电机原理,建立自旋转喷头稳态运行时电势、转矩和功率三个平衡方程,并以此设计了61旋转喷头电磁限速装置,将其用在煤层钻孔方面,确保了旋转射流在不同输入功率下,具有良好的打击成型性能,然后建立了影响旋转喷头转速的各主要因素之间的关系式,并讨论转速与射流功率之间的关系,最后做出实物样品,经现场试用后达到预期效果。     

铜酞青LB膜与金属界面光二次谐波现象

从铜酞菁的衍生物（copper tetra-tert-butyl phthalocyanine,CuttbPc）LB膜与金属（A1）界面处观察到较强的光二次谐波信号.初步认为其原因是界面上所形成的空间电荷感应电场打破了分子原有的对称性.运用四层物理模型来分析界面中的非线性光学过程,计算出二次谐波信号强度与膜厚、偏振角及入射角的依赖关系,与实验数据符合较好.研究结果表明,光二次谐波信号的产生与界面静电现象有密切关系,可作为检测界面空间电荷感应电场、揭示其产生物理机制的有力工具.     

Analysis of Second-Harmonic Generation from CuttbPc LB Film／Metal Interface

Second-harmonic generation signals from a CuttbPc LB film deposited on metal (Al or Au)-glass substrates were investigated. It was observed that there were two second-harmonic peaks at the wavelength of 1060 and 1250nm in the CuttbPc/Al film, but only one peak at 1050nm in the CuttbPc/Au film. Meanwhile the surface electric potentials (SEP) at the interfaces of LB film/metals were also measured using a Kelvin probe. The SEP in the CuttbPc/Al decreases and eventually approaches a saturated value of -1.0V as the film thickness increases, while the SEP in the CuttbPc/Au is nearly zero. Based on the experimental results and theoretical analysis, it was considered that the space-charge-induced electric field makes a main contribution to the second-harmonic generation at 1250nm in the CuttbPc/Al film.     

Second harmonic generation at the interface of copper tetra-tert-butyl phthalocyanine Langmuir-Blodgett film/metal

As one of the most primitive nonlinear optical phenomena, optical second harmonic genera-tion (SHG) has been investigated for half a century and it has become a very useful spectroscopic tool in the study of surface and interface[1—3]. It was theoretically shown that the SH signal cannot be generated in a centrosymmetric system. However, the generation of SH signal from the centro-symmetric molecules such as fullerene (C60) and CuPc has been detected[4—7]. In our recent ex-periments, an …     

实验力学面向经济建设事例

冷轧机机架工作应力状态的光弹性实验研究冷轧机机架在使用过程中,发现在压下螺母孔内的过渡圆弧处,机架的上横梁圆孔的侧边缘处,以及窗口圆角沟槽处,多发生开裂现象,而致使整个机架报废.为了分析其开裂原因,为轧机设备改造和为设计新轧机提供参考数据,以避免机架报废所带来的经济损失,已由沈阳重机厂、太原钢铁公司和东北重型机械学 ...     

Measurement of Surface Potential at Metal／Organic-Material Interfaces by Electro-Absorption Method

The surface potential built-in vacuum deposited phthalocyanine (Pc) film on aluminium electrode is investigated by the electro-modulation method. To avoid the influence of charge injection, a sandwiched cell (Al-Pc-air-ITO) is fabricated. The modulation signal, which depends on the external electric field intensity, is detected.The properties of electro-absorption (EA) and electro-reflectance (ER) signals are analysed. The existence of the surface potential at the metal/organic-material interface induces i f referenced ER signals. As a result, the surface potential built across the vacuum-deposited Pc film on the aluminium electrode is estimated to be 1.23 V.     

系统平衡稳定性问题的局部性研究

为了深入了解系统平衡稳定性的局部性问题,采用基于势能驻值定理等普遍意义的力学原理,针对扰动强弱和系统位形局部微观结构特性,对平衡的性质作深入探讨.给出稳定平衡的进一步划分,对以上平衡稳定性质的划分给出数学上的定性描述并且结合实例对其进行应用分析.得出平衡稳定性不仅与所处势能的极值有关,而且与工程允许扰动量及工程扰动量等极值点的位形有关.     

三重介质油藏负表皮系数水平井瞬态压力的有效算法

为了更好地描述多尺度孔隙碳酸盐岩油藏的渗流特征,建立考虑多重窜流的三重介质油藏水平井不稳定试井模型,并对模型求解,绘制典型曲线。通过对水平井与直井在不稳定渗流早期流线特征的相似性分析,以及对不同表皮系数定义的正确区分,确定各表皮系数间的关系,进而引入水平井有效井径的概念。结果表明:多尺度孔隙碳酸盐岩油藏水平井开采下的渗流过程可能出现9个流动阶段;该方法与传统方法相比计算结果可靠,彻底解决了负表皮系数水平井瞬态压力计算的难题,适用范围广。     

预制定向裂纹水力压裂延伸数值模拟

针对目前水力压裂数值模拟对水力压裂裂纹的动态扩展的方向、路径、范围等动态参数研究较少的客观现实以及预制定向裂纹后水力压裂延伸规律的实际工程需要。建立了裂纹失稳扩展判据及其水力压裂裂纹延伸的数学模型并进行了数值模拟,较系统地研究了固井质量完好条件下预制不同方向裂纹在水力压裂过程中的裂纹延伸规律：固井质量不好的条件下,压裂液将会在水泥套简与井壁之间流动,裂纹将在垂直于最小主应力的方向上形成两条裂纹,而不是在预制的方向上起裂。这些问题的研究对完善我国水力压裂技术理论和提高水力压裂技术的应用水平有重要意义。     

金属／聚酰亚胺LB薄膜界面特性研究

为提高有机电子器件的性能,制备了不同的厚度的聚酰亚胺（PI）LB薄膜,测量了不同厚度的聚酰亚胺LB薄膜与金电极接触时的表面电压,分析了金属／PILB薄界面的电荷分布情况,发现电荷主要集中在界面附近,测定了金属／PILB／金属结构的电流－电压关系,用金属热电子发射和场致发射的模型对其进行了分析,结果表明电子发射机理受温度和电场强度的控制,实验结果与模型符合得较好。