单缝衍射法测量磁致伸缩系数

根据单缝衍射原理设计光路,通过数字图样处理方法处理高清摄像头采集的衍射图像,搭建一套精确测量铁磁材料在弱磁场中磁致伸缩系数的实验装置.该装置具有测量方法简单,精确度高,能够快捷测量的特点.

Improvements of Traditional Laser Fraunhofer Diffraction Experiment Using Digital Image Processing Method

We present an improved digital image processing(DIP)method to calculate the widths of single slits.Different from the traditional laser Fraunhofer diffraction experiment in college physical experiments,by performing fast Fourier transform,inverse fast Fourier transform and the nonlinear leastsquare fitting on the diffraction pattern taken by a camera,the DIP method can quickly return an analytic expression,whose period is used to calculate widths of single slits.By comparing the measured results by the DIP method and the successional difference(SD)method,we find that for a single slit whose width is 60372μm,the DIP method is more accurate.Experimental results show that for single slits with widths between 40μm and 160μm,the relative error of the DIP method is less than 2.78%.Also,the DIP method can be used to measure the diameter of filament and fibres online in real time.

应用型本科物理类科技作品设计与实践

物理类科技创新实验是大学物理实验课程的创新性补充,是培养学生实践能力、创新和科学探究能力的重要途径。探讨了在多学科交叉背景下以学生为主体的物理类科技作品创新性实验的可行性,结合参加物理实验竞赛的实际工作,从探究式物理实验选题、科技作品设计与创作、教学过程实施与评价等方面分析了应用型本科物理类科技作品创作思路,从而实现培养学生创新精神和提升研究能力的目的。

Au@SiO_(2)核-壳层单晶八面体纳米棒光吸收性质的研究

包覆材料改变了单一材料的力学、光学性质。利用离散偶极近似(Discrete Dipole Approximation,简称DDA)的方法,系统研究二氧化硅壳层、尺寸及形貌等因素对Au@SiO_(2)核-壳层单晶八面体纳米棒光学吸收谱峰值、峰位及其近场分布的影响。研究表明SiO_(2)壳层包覆的Au纳米棒的光学吸收谱同样表现为横向和纵向吸收峰。随着SiO_(2)壳层厚度增加,Au@SiO_(2)核-壳层单晶八面体纳米棒横向和纵向吸收缝的强度明显减弱,横向吸收峰的位置发生微小的蓝移,而纵向吸收峰位发生明显的红移。SiO_(2)壳层在提高纳米棒硬度的同时,改变光学吸收峰的峰值和峰位,削弱了Au核表面等离子体共振强度(Surface Plasma Resonance-SPR)。