钒-5-溴水杨基荧光酮-氯酸盐体系极谱催化波的研究

在pH4.1的乙酸盐缓冲底液中,钒能与5-溴水杨基荧光酮形成络合物,并吸附在汞电极上,在氯酸盐存在下,在V(Ⅴ)的电极还原过程中形成催化波。用单扫二阶导数极谱法测定时,钒浓度在L.0×10-8～1.0×10-6mol·L-1范围内与峰高成正比关系,检出限为5.0×10-9mol·L-1。测得电活性络合物的组成为V(Ⅴ)5-Br-SAF＝11。平行催化反应的速率常数k=1.9×103(mol·L-1)-1·s-1。     

Zn-5-溴水杨基荧光酮-酒石酸钠-CTMAB 四元显色体系的研究与应用

研究了在碱性介质中 ,Zn-5 -溴水杨基荧光酮 -酒石酸钠 -CTMAB体系光度法测定微量锌的新方法。四元体系的最大吸收峰在 5 6 0 nm处 ,表观摩尔吸光系数为 1.0 8× 10 5 L·mol-1·cm-1。配合物的稳定常数 K′稳 =1.6 7× 10 1 2 ,锌含量在 0～ 10μg/2 5 m L范围内符合比耳定律。此法已用于水样和药物中锌含量的直接测定     

新型光纤光栅扭转传感器研究

报道了一种新型光纤光栅扭转传感器的基本原理和传感结构,推导了扭转测量的理论公式,该传感器的扭角与光纤光栅中心波长的变化呈线性关系.在±40°扭角范围内,技术上实现了灵敏度为10.715°/nm的扭转传感.     

Test and simulation of a MICROMEGAS detector

We report on the recent test results of a MICROMEGAS detector in terms of position resolution, time resolution and efficiency. With a Ar + CO₂ (10%) gas mixture and a strip pitch of 200 μm an accuracy of 80 μm in sigma on the position has been measured. The time resolution is better than 20 ns and a cosmic ray detection efficiency of 94% was obtained. A Monte Carlo simulation indicates that transverse diffusion, gain fluctuation and electronic noise limit the position resolution.     

甜茶叶中甜茶苷的UPLC-MS/MS分析

采用超高效液相色谱-质谱联用法测定广西特产甜茶叶中的主要甜味成分甜茶苷的含量.样品经前处理后以Acquity UPLC BEH C18柱为色谱柱,流动相为乙腈(含体积分数为0.1％甲酸)-蒸馏水(含体积分数0.1％甲酸),梯度条件为10min乙腈相体积由20％变化到65％,柱温35℃,进样量5μL,流速为0.15mL/...     

关于几乎等距嵌入的一个注记

本文将指出：对于足够小的ε＞ ０,不存在从无穷维“抽象 ＬＰ”空 间（０＜ ｐ＜∞）到空间（ｃ）的ε－等距线性算子．     

基于闪耀光纤光栅的折射率传感技术实验研究

提出了一种基于闪耀光纤光栅传感技术的折射率测量新方法,即采用SLED作为光源,通过检测闪耀光纤光栅透射谱强度实现折射率的测量.实验证明,当环境折射率在1.372 3~1.453 2之间变化时,闪耀光纤光栅透射功率从0.611~0.472 mW线性下降,其灵敏度达到1.718 μW/（0.001折射率变化）.该检测方法具有结构简单、无需波长检测、灵敏度高、易于工程化等优点.     

Demodulation method combining virtual reference interferometry and minimum mean square error for fiber-optic Fabry–Perot sensors

We propose a cavity length demodulation method that combines virtual reference interferometry(VRI) and minimum mean square error(MMSE) algorithm for fiber-optic Fabry–Perot(F-P) sensors. In contrast to the conventional demodulating method that uses fast Fourier transform(FFT) for cavity length estimation,our method employs the VRI technique to obtain a raw cavity length, which is further refined by the MMSE algorithm. As an experimental demonstration, a fiber-optic F-P sensor based on a sapphire wafer is fabricated for temperature sensing. The VRI-MMSE method is employed to interrogate cavity lengths of the sensor under different temperatures ranging from 28°C to 1000°C. It eliminates the "mode jumping" problem in the FFT-MMSE method and obtains a precision of 4.8 nm, corresponding to a temperature resolution of 2.0°C over a range of 1000°C. The experimental results reveal that the proposed method provides a promising, high precision alternative for demodulating fiber-optic F-P sensors.