大型非球面反射镜的柔性光学制造技术

提出了柔性光学制造技术 (FOMT)的概念。介绍了计算机控制小工具抛光 (CCOS)和计算机控制应力盘(CCSL)抛光的技术特点 ;讨论了CCOS在抛光过程中的工艺技术优化方案 ;给出了应力盘变形的数学物理模型及在周边 12个驱动器的作用下应力盘全口径和 80 %口径范围内的变形仿真结果 ;研究了在全口径 φ5 0 0mm盘上的工程实现途径及应力盘与机床CNC的通讯关系以及抛光工艺研究 ;分析了CCOS、应力盘抛光和经典法抛光技术的综合运用 ;探讨了柔性光学制造技术发展的必然趋势。     

主动抛光盘磨制非球面的工艺与面形检测

主动抛光盘技术特别适用于磨制焦比大的深度非球面,能够根据需要对抛光盘面实时地主动变形成偏轴非球面来磨制非球面镜面。它具有较高的磨削速率和较大范围内的自然平滑(无切带)。用计算机控制磨制,可以像加工球面一样来加工一个深度的非球面。介绍了用国内首次研制成功的主动抛光盘对加工直径910mm、焦比F/2的抛物面镜的工艺方法的初步探讨,并给出了抛物面镜的检验方案和检测结果。     

弹性半空间地基上预应力中厚矩形板的弯曲

基于Reissner-Mindlin一阶剪切变形理论,讨论在预加面内机械荷载或预加温度场作用下,弹性半空间地基上四边自由中厚矩形板的弯曲问题。把地基看作三维弹性半空间体,考虑地基变形的衰减。用一组数学上完备的二元多项式作为位形函数,采用pb-2 Rayleigh-Ritz法求得四边自由中厚矩形板的挠度和弯矩,并讨论了初应力对板的挠度和弯矩的影响。     

应变液晶散射偏光片的试制

介绍了聚合物分散液晶(PDLC)和应变液晶(SLC)以及散射偏光片的概念,实验制备了应变液晶散射偏光片样品,样品由两张胶片夹层聚合物分散液晶膜在紫外光固化过程中施加剪切应力所形成。给出了样品偏光显微镜照片和可见光分光光度计偏光特性光谱分析。实验结果表明,应变液晶散射偏光片样品外观半透明,在正交偏光场中转动样品有颜色变化,通过样品观察液晶显示器屏幕,在不同角度下有透射和散射作用,在偏光显微镜中观察样品有衬垫料被拉动的痕迹,光谱分析显示样品在绿光550nm波长处最大透光率T∥≈50%,最小透光率T⊥≈5%,偏振度P≈82%。实验结果对于研制实用的拉伸液晶散射偏光片具有参考意义。     

Description of the elastic deformation and degradation of elastic properties of dispersedly failing isotropic materials

A model is put forward for describing the elastic deformation of a quasi-homogeneous isotropic material capable of accumulating scattered microdamages during loading, which eventually leads to its total failure. The degree of damage of the material at a point is characterized by a centrosymmetric scalar function on the unit sphere, named the damage function, whose values depend on a dimensionless equivalent stress. This function is approximated by a fourth-rank tensor, which is used to construct a constitutive relation between stresses and strains in a differential form. By way of example, the elastic deformation of concrete and the degradation of its linearly elastic properties are described, and the basic three-dimensional sections of the corresponding strength surface are constructed. __________ Translated from Mekhanika Kompozitnykh Materialov, Vol. 42, No. 2, pp. 193–208, March–April, 2006.     

一种大口径大非球面度天文镜面磨制新技术

主动抛光盘技术是近年来因天文望远镜的口径越来越大,焦比越来越快而发展起来的一种能够根据需要将抛光盘面实时地主动变形成偏轴非球面来磨制大口径非球面度高精度天文镜面的磨制技术。非球面表面的曲率不仅各点不一致,而且同一点的径向与切向曲率也不相同,所以经典的大的抛光盘不可能使其表面形状始终与所接触的非球面表面形状相吻合;常用的小磨盘抛光的致命缺点是解决不了高频切带,抛光效率也低。而主动抛光盘技术正好解决这些难题。与传统方法相比,它具有较高的磨削速率和较大范围内的自然平滑(无切带)。这是一种用计算机控制的磨镜技术,通过它可以像加工球面一样来加工一个深度的非球面。介绍了我国成功研制的主动抛光盘以及它在直径910mm,焦比F／2抛物面镜加工中的成功应用和加工的结果,以及此项技术将在2m以上直径天文镜面,特别是30m巨型天文光学／红外望远镜的分块子镜磨制中的应用前景。     

金川二矿区14行风井再加固方案的可行性研究

金川二矿区14行风井破坏返修后,新井筒上部又出现了两条较大的近水平的裂缝,对此,进一步提出对返修后井筒的再加固方案。本文结合金川矿山地表岩移GPS监测结果,采用数值模拟的方法,对再加固方案的可行性进行了论证。结果表明,实施浅部的加固措施并没有改变竖井受采动影响的程度,更未实现预期的加固效果。继而对加固锚索施加预应力来检验加固方案本身的适应性,发现加固前后竖井井壁位移和应力的大小、分布也没有明显变化。可见,对于采动影响区内的竖井,采取单纯浅部加固的方案并无效果。最后,综合考虑14行风井破坏的原因、前期加固方案存在的问题和岩移趋势,提出了进一步加固措施的建议。     

Strain Relaxation in an Alloy Film with a Rough Free Surface

We study strain relief by surface roughness and composition variation in a stressed alloy film. Instead of using common perturbation techniques, we derive a rigorous relaxation formula based on the energy approach in the case of slightly undulating surface and fluctuating composition. We do not require any a priori assumption of elastic isotropy or identical material properties between film and substrate in deriving our result. We show that the change of elastic energy is negative, giving rise to energy relief due to the presence of free surface. We apply our result to the study of compositional and morphological instabilities of a stressed thin layer with a free surface. The critical wave number of instability is determined by the competition between the destabilizing influence of elastic strain energy and the stabilizing influence of chemical and surface energies.     

基于弹性力学的应力加工方法有限元分析

基于弹性力学理论,对应力加工方法的原理、算法及玻璃薄板对复杂面型的模拟进行了研究。在球面镜周边分布力和力矩的状态下对球面变形为轴对称非球面进行了分析,以抛物面镜为例,采用有限元法对玻璃薄板周边施加均布弯矩后产生的变形量和最大应力进行了模拟、分析和仿真计算,得出的仿真结果与球面和抛物面之间的理想变形量进行比较,验证了基于弹性力学的应力加工方法加工旋转对称非球面理论的正确性。     

Stability-indicating method for the determination of assay and quantification of impurities in amlodipine–atorvastatin combination dosage form by RP-HPLC

A simple stability-indicating RP-HPLC method was developed and validated for quantification of amlodipine, atorvastatin, and its impurities on Waters HPLC using Unisol C₁₈ 5?µm, 250?×?4.6?mm column in their combined tablet dosage as per ICH guidelines. The gradient (T/%B) at 0/42, 18/42, 22/75, 30/75, 32/42, and 35/42 of 40?mM 4.7 pH ammonium acetate as mobile phase A and acetonitrile as mobile phase B of flow rate 1.5?mL/min and 240?nm wavelength. Peak purity compiled for amlodipine and atorvastatin in all stressed conditions. For impurities: Precision was found in between 1.5 and 3.6%. The limit of detection and quantification for amlodipine, amlodipine impurity A, and atorvastatin was found to be 0.06 and 0.18?µg/mL, for atorvastatin Impurity A, B, C, and H was determined as 0.04 and 0.11?µg/mL, for Atorvastatin Impurity D was measured as 0.11 and 0.28?µg/mL, respectively. The linear regression achieved >0.9999 from 0.22 to 7.5?µg/mL. Recovery was observed in between 97 and 101%. For assay: Precision was determined in between 0.1 and 0.2%. The linear regression achieved >0.9999 for amlodipine and atorvastatin. Recovery ranged from 100 to 101%. The validated method was found to be accurate, precise, reliable, and robust to determine the assay as well as impurities in amlodipine–atorvastatin combination dosage formulation.