超声辅助提取-固相萃取土壤中头孢菌素C的高效液相色谱法定量检测

建立了一种采用超声辅助提取(UAE)、强阴离子交换固相萃取(SAX-SPE)净化、高效液相色谱(HPLC)测定土壤中残留头孢菌素C(CPC)简单、快速方法。 样品以超纯水为提取剂,超声辅助提取,SPE柱子以3 mL甲醇和3 mL水活化,采用5 mL的10%甲醇水溶液作为淋洗液,2 mL的5%甲酸水溶液/甲醇溶液(体积比50：50)进行洗脱,高效液相色谱紫外检测器(HPLC-PDA)测定,检测波长λ=254 nm,柱温30 ℃ ,流动相为0.1%甲酸水溶液/甲醇溶液(体积比95：5)对土壤中不同加标浓度的CPC进行检测,方法的回收率在77.9%~98.9%,标准偏差范围为5.0%~6.3%(n=5),方法检出限(LOD)为340.4 μg/kg,定量限(LOQ)为1126.8 μg/kg。 同时采用此方法检测分析新疆某药厂附近阳性土壤样品,不同批次土壤样品结果分别为:检出(低于定量限)、1532.1 μg/kg。     

1.55μm相干激光测风雷达平衡式探测接收实验

研究了用于相干激光测风雷达信号接收的平衡式探测接收技术.推导出了平衡式相干探测过程的数学模型和信噪比表达式,并通过仿真软件对该模型进行了模拟仿真.在同等输入条件下,当平衡式相干探测系统的最佳分束比范围在[0.293,0.707]时,其信噪比比普通相干探测的信噪比高.此外,平衡式探测接收还具有判断风向的功能,最后通过实验验证了仿真结果.     

多光束激光外差高精度测量玻璃厚度的方法

利用基于激光外差测量技术和激光多普勒技术的非接触式多光束激光外差测量方法,得到了光电探测器输出电流的谐波表达式.讨论了该测量方法用于玻璃厚度超精密测量的可行性及理论依据,并利用Matlab软件对不同情况进行了仿真实验.结果表明：该方法在不同入射角时测量平板玻璃厚度最大的误差为0.3%,明显比其他测量方法精度高. 关键词： 外差探测 多光束激光外差 激光多普勒技术 非接触式测量     

多普勒振镜正弦调制多光束激光外差二次谐波测量微冲量

提出了一种正弦调制多光束激光外差二次谐波测量微冲量的新方法,将激光与工质靶作用产生的微冲量转化为扭摆的转动角度测量,基于激光外差技术和多普勒效应,把待测转角信息加载到外差信号的频率差中,经信号解调后可以得到待测转角值,通过多次测量取平均值的方法可以提高待测转角的测量精度,从而提高微冲量的测量精度。利用这种新方法,以PVC+2%C为工质靶,利用MATLAB仿真测量了激光与工质靶作用产生的微冲量,结果表明:该测量的最大相对误差小于0.8%。     

1.55 μm相干激光测风雷达平衡式探测接收实验

研究了用于相干激光测风雷达信号接收的平衡式探测接收技术.推导出了平衡式相干探测过程的数学模型和信噪比表达式,并通过仿真软件对该模型进行了模拟仿真.在同等输入条件下,当平衡式相干探测系统的最佳分束比范围在[0.293,0.707]时,其信噪比比普通相干探测的信噪比高.此外,平衡式探测接收还具有判断风向的功能,最后通过实验验证了仿真结果.     

A method of measuring micro-impulse with torsion pendulum based on multi-beam laser heterodyne

In this paper, we propose a novel method of multi-beam laser heterodyne measurement for micro-impulse. The measurement of the micro-impulse, which is converted into the measurement of the small tuning angle of the torsion pendulum, is realized by considering the interaction between pulse laser and working medium. Based on Doppler effect and heterodyne technology, the information regarding the small tuning angle is loaded to the frequency difference of the multi-beam laser heterodyne signal by the frequency modulation of the oscillating mirror, thereby obtaining many values of the small tuning angle after the multi-beam laser heterodyne signal demodulation simultaneously. Processing these values by weighted-average, the small tuning angle can be obtained accurately and the value of the micro-impulse can eventually be calculated. Using Polyvinylchlorid+2%C as a working medium, this novel method is used to simulate the value of the micro-impulse by MATLAB which is generated by considering the interaction between the pulse laser and the working medium, the obtained result shows that the relative error of this method is just 0.5%.     

Numerical investigation of multi-beam laser heterodyne measurement with ultra-precision for linear expansion coefficient of metal based on oscillating mirror modulation

This paper proposes a novel method of multi-beam laser heterodyne measurement for metal linear expansion coefficient. Based on the Doppler effect and heterodyne technology, the information is loaded of length variation to the frequency difference of the multi-beam laser heterodyne signal by the frequency modulation of the oscillating mirror, this method can obtain many values of length variation caused by temperature variation after the multi-beam laser heterodyne signal demodulation simultaneously. Processing these values by weighted-average, it can obtain length variation accurately, and eventually obtain the value of linear expansion coefficient of metal by the calculation. This novel method is used to simulate measurement for linear expansion coefficient of metal rod under different temperatures by MATLAB, the obtained result shows that the relative measurement error of this method is just 0.4%.     

Pickering多重乳状液的一步法合成及形成机理研究

使用锂皂石层状纳米颗粒与表面活性剂(Span80)复配制备乳状液的过程中, 在乳化之前对锂皂石颗粒水分散体系进行稀释, 则可以通过一步法制备出性能稳定的W/O/W型Pickering多重乳状液. 研究了Span80浓度、锂皂石浓度以及稀释用水的量对生成乳状液的类型及稳定性的影响规律, 对一步法合成Pickering多重乳状液的成因及机理进行了探讨和分析. 实验结果表明, 对锂皂石颗粒水分散体系的稀释是一步法合成稳定Pickering多重乳状液的关键因素, 稀释用水的量决定了多重乳状液中的内水相体积. 随着Span80浓度的增加, 多重乳状液的粒径减小, 稳定性迅速增加. 锂皂石颗粒的浓度能够影响乳状液的类型, 但对乳状液的稳定性以及乳状液的粒径影响不大. 锂皂石颗粒在水分散体系中缓慢的扩散速率是一步法合成Pickering多重乳状液的主要原因.     

光束分束比对2μm平衡式相干探测系统信噪比影响的实验研究

给出了平衡式相干探测系统的一般信噪比数学模型,对该数学模型和普通单源相干探测系统的信噪比模型进行了数值仿真对比研究.仿真结果表明,当平衡式相干探测系统中的光电探测器理想匹配时,其系统的信噪比以分束比系数等于0.5呈对称分布;而当光电探测器失配时,系统的最大信噪比所对应的最佳光束分束比发生偏离.最后搭建了2μm平衡式相干...