基于多模-单模-多模结构和光纤布拉格光栅同时测量温度和折射率

利用单模光纤(SMF)中的包层模与纤芯导模之间的干涉,提出了一种基于多模-单模-多模(MSM)结构与布拉格光栅(FBG)级联可同时测量温度和折射率的传感器.基于MSM结构的干涉谱和FBG的透射峰对温度和折射率具有不同响应灵敏度的特点,利用敏感矩阵实现了对温度和折射率的同时测量.实验测得MSM结构和FBG的温度灵敏度分别为0.055 2 nm/℃和0.015 8 nm/℃,MSM结构的折射率灵敏度为109.702 nm/RIU,而FBG对折射率变化不敏感.温度和折射率的测量精度分别为士0.32℃和士0.002 3.实验显示提出的MSM结构的温度灵敏度比单模-多模-单模(SMS)结构传感器提高了5倍,同时由于SMF中的包层模对外界环境的变化较敏感,该MSM结构也可应用于其他传感领域.     

Highly birefringent photonic crystal fibers with flattened dispersion and low confinement loss

A highly birefringent index-guiding photonic crystal fiber (PCF) with flattened dispersion and low confinement loss is proposed by introducing two small air holes with the same diameter in the core area. The fundamental mode field, birefringence, confinement loss, effective mode area and dispersion characteristic of the fibers are studied by the full-vector finite element method (FEM). Simulation results show that a high birefringence with the order of 10 -3 and a low confinement loss of 0.001 dB/km are obtained at 1550 nm. Furthermore, flattened chromatic dispersion from 1450 nm to 1590 nm is obtained.     

厚度对室温沉积ZnO:Al薄膜光电特性的影响

利用直流磁控溅射法, 在室温玻璃衬底上制备了具有良好附着性的多晶ZnO∶ Al(ZAO)薄膜. 比较了室温下获得的薄膜与衬底加热条件下所得薄膜的结晶程度, 研究了厚度对室温条件下制备的ZAO薄膜表面形貌、电学性能及紫外-可见-近红外光区透光性的影响. 结果表明, 室温条件下制备的ZAO薄膜也具有(002)面择优取向, 随着膜厚的增加薄膜晶粒化程度提高, 载流子浓度和迁移率增大, 电阻率下降, 薄膜在紫外光区的吸收边发生红移, 在可见光区的平均透过率降低, 在近红外光区的透过率随厚度的增加而减小. 厚度为1200 nm的ZAO薄膜具有最佳光电综合性能, 其电阻率为7.315×10~(-4) Ω·cm, 方块电阻为6.1 Ω/□, 可见光区平均透过率达到82%, 波长为550 nm处的透过率为87%.     

原子吸收法测定糖尿病人血清中微量元素

糖尿病是我国发病率较高的疾病之一、并主要通过其并发症威胁人类。测定糖尿病及其并发症血清中的微量元素，可为研究糖尿病发病机理、预防和诊治糖尿病提供依据。用常规的火焰原子吸收法，测定多个元素时所需样品量大，样品不易获得，而且测定过程中管路容易被堵塞。本文测定过程中结合使用微量脉冲进样法，测定了２９例糖尿病病人和２６例糖尿病并发症病人血清中的钙、镁、锌、铜、铁，并和２８例健康人血清中相应元素进行了比较。     

Magnetic field sensor based on peanut-shape structure and multimode fiber

An all fiber magnetic field sensor with peanut-shape structure based on multimode fiber (MMF) is proposed and experimentally demonstrated. The sensing structure and magnetic fluid (MF) are both encapsulated in capillary, and the effective refractive index of MF is affected by surrounding magnetic field strength. The measurement of magnetic field is realized by observing the wavelength drift of interference peak. The transmission spectrum generated by Mach-Zehnder interferometer (MZI) includes core-core mode interference and core-cladding mode interference. Experimental results demonstrate that the core-cladding mode interference is sensitive to magnetic field, and the magnetic field sensitivity is 0.047 8 nm/mT. In addition, two kinds of interference dips are sensitive to temperature, and the sensitivities are 0.060 0 nm/°C and 0.052 6 nm/°C, respectively. So the simultaneous measurement of magnetic field strength and temperature can be achieved based on sensitivity matrix. This work has been supported by the National High Technology Research and Development Program of China (No.2013AA014200), the National Natural Science Foundation of China (No.11444001), and the Municipal Natural Science Foundation of Tianjin (No.14JCYBJC16500). E-mail:13821538563@163.com      

SPME-GC/MS方法分析水样中偏二甲肼降解产物

本文使用SPME-GC/MS技术分析不同时间水中偏二甲肼降解产物浓度变化规律,并得到SPME对偏二甲肼降解产物的最佳萃取条件。该方法快速、便捷,具有时间短、灵敏度高、操作简便等优点。     

一种简易微波反应装置

本文简述了我们研制的简易微波反应装置的制作及应用,利用该装置可以大大加快化学反应的速度。     

原子吸收法测定乙肝病毒携带者血清中钙,镁,锰,镉的含量

本文用原子吸收光谱法测定了３０例乙肝病毒携带者和３０例正常人血清中的钙、镁、锰、镉。结果表明，乙肝病毒携带者血清中钙显著降低，而镁、锰、镉与对照组我明显关系。     

肼类推进剂气体传感技术研究进展

概述了多种检测肼类推进剂气体传感器的原理、特点和应用,分析比较了各种肼类气体传感器的优缺点,展望了肼类气体传感检测技术的发展趋势.     

100t铁路起重机箱形伸缩吊臂结构的模糊优化设计

对100 t铁路救援起重机箱形伸缩吊臂进行模糊优化设计。考虑强度、刚度、稳定性和几何参数约束的模糊性,以吊臂自重最轻为目标,吊臂截面参数为设计变量,建立了非对称模糊优化模型,采用最优水平截集法求解。应用混合离散变量优化的MDOD优化子程序和遗传算法,分别编写相应的优化程序进行计算,在传统优化的基础上使吊臂自重降低了9%左右。