高灵敏度离轴积分腔输出光谱技术

利用离轴积分腔输出光谱技术,采用同时扫描激光和谐振腔腔长的方法,使用分布反馈布拉格二极管激光器探测了1.573μm附近CO2的吸收光谱,得到很好的信噪比和灵敏度,探测灵敏度达到4×10-8cm-1(信噪比为2,1 s积分时间)。用非线性最小二乘拟合吸收谱线方法对积分腔输出光谱已经不再适用,会造成自加宽系数变宽为实际自加宽系数的2.39倍左右,对空气加宽系数测量影响较小。为了得到正确的谱线线宽参量,应该对吸收系数进行拟合,该结论从理论和实验上得到了证明。     

多轴冲击不同测试方法下测试结果的比较

采用ISO 6603-2标准和ASTM D3763标准对多轴冲击测试中的挠度、载荷及能量进行了研究.结果表明,在不同冲击速度条件下分别采用ASTM D3763标准和ISO 6603-2标准测出的挠度、载荷及能量变化规律一致,即速度越小,挠度、能量越大,载荷越小;在相同冲击速度条件下采用ASTM D3763标准测出的撞击点挠度比采用ISO 6603-2标准测定值的大,载荷及能量比采用ISO 6603-2标准测定值小.     

Three-Dimensional Analytical Formula for Oblique and Off-Axis Gaussian Beams Propagating through a Cat-Eye Optical Lens

Based on the Collins formula in a cylindrical coordinate system and the method of introducing a hard aperture function into a finite sum of complex Gaussian functions, an approximate three-dimensional analytical formula for oblique and off-axis Gaussian beams propagating through a cat-eye optical lens is derived. Numerical results show that a reasonable choice of the obliquity factor would result in a better focus beam with a higher central intensity at the return place than that without obliquity, whereas the previous conclusion based on geometry optics is that the highest central intensity could be obtained when there is no obliquity.     

聚碳酸酯非比例多轴棘轮行为的实验研究

在室温下,对聚碳酸酯进行了一系列非比例加载路径下的循环变形实验。首先讨论了不同非比例路径对聚碳酸酯多轴棘轮行为的影响,其次讨论了轴向平均应力和应力幅值及其历史的影响。实验结果表明:聚碳酸酯在不同非比例路径下均产生了明显的棘轮行为,且棘轮变形的大小明显依赖于加载路径的形状;非比例多轴棘轮行为明显地依赖于轴向平均应力和应力幅值的大小及其历史。     

Observation of tropospheric NO_2 by airborne multi-axis differential optical absorption spectroscopy in the Pearl River Delta region,south China

An airborne multi-axis differential optical absorption spectroscopic （AMAX-DOAS） instrument was developed and applied to measure tropospheric NO2 in the Pearl River Delta region in the south of China. By combining the measurements in nadir and zenith directions and analyzing the UV and visible spectral region using the DOAS method, information about tropospheric NO2 vertical columns was obtained. Strong tropospheric NO2 signals were detected when flying over heavilly polluted regions and point sources like plants. The AMAX-DOAS results were compared with ground-based MAX-DOAS observations in the southwest of Zhuhai city using the same parameters for radiative transport calculations. The difference in vertical column data between the two instruments is about 8%. Our data were also compared with those from OMI and fair agreement was obtained with a correlation coefficient R of 0.61. The difference between the two instruments can be attributed to the different spatial resolution and the temporal mismatch during the measurements.     

平面掩埋式半圆柱梯折棒的光线轨迹和聚焦特性

本文从光线方程出发，详细讨论了平面掩埋式半圆柱梯折棒的近轴光学特性，得到了光线轨迹方程和成像矩阵。并对高斯参量进行了理论分析，分析结果与实验数据符合很好。     

正交轴逆流色谱法分离标准蛋白质及实际样品

 以m(质量分数为 12 .5 %的PEG80 0 0 )∶m(质量分数为 2 5 %的磷酸氢二钾 ) =1∶1或m(质量分数为 12 .5 %的PEG80 0 0 )∶m(质量分数为 30 %的磷酸氢二钾 ) =1∶1为溶剂系统 ,用下相作流动相 ,上相作固定相 ,操作时采用5 0 0r/min的转速和 6 0mL/h的流动相流速 ,考察了正交轴逆流色谱法对标准蛋白质及羊肚菌糖蛋白和枸杞糖肽的分离情况。将结果与高效液相色谱分离结果相比较 ,前者在分离度损失不大的基础上提高了进样量 ,证明了其用于制备的有效性 ,从而为分离制备天然生物大分子提供了一个新方法。     

非手性分子识别的一种新方法

详尽地讨论了分子的四种对称因素ｉ、σ、Ｃｎ、Ｓｎ之间的联系，把它们统一为Ｓｎ轴。阐明了Ｓｎ轴和非手性分子的１∶１对应关系。在揭示Ｓｎ轴实质的基础上，发现了非经典的Ｓ′ｎ轴，并从逻辑推理中导出了非手性分子识别的新方法，旋转镜影法。     

椭圆运动中轴长和轴方位的简捷计算

本文介绍了一种计算椭圆运动中轴长和轴方位的简捷方法。