Determination of iron(II) with 2-nitroso-5-diethylaminophenol by thermal lens spectrophotometry using a semiconductor laser as a light source

The concentration of Fe(II) ion is determined by chelation with 2-nitroso-5-diehtylaminophenol and liquid-liquid extraction into chloroform. Light absorption at 780 nm is measured with a thermal lens spectrophotometer equipped with a semiconductor laser as a light source. The enhancement factor achieved experimentally is 47. The detection limit of Fe(II) ion is 8.1 × 10^?9 M, which is 3–4 times better than that obtained by conventional absorption spectrometry, and is governed by the background signal originating from Fe(II) impurity in the reagent.     

毛细管微池激光热透镜光谱分析方法研究

采用毛细管为测定微池,研究了毛细管微池激光热透镜光谱分析方法。理论上给出了毛细管微池激光热透镜光谱分析表达式。探讨了毛细管微池光反射的影响及其在光路位置特征、有机溶剂增强效应等。应用毛细管微池激光热透镜光谱分析于钼蓝法测定磷和浊点萃取测定孔雀石绿。结果表明建立的毛细管微池激光热透镜光谱分析方法,具有简单易行、高灵敏度的特点,适用于微量样品的分析测定。该研究不仅对于微量样品的测定具有应用价值,而且对于激光热透镜光谱分析法在绿色分析化学中的应用具有积极的促进作用。     

分光光度法测定角膜接触镜护理液中聚季胺盐-1含量

利用分光光度法测定角膜接触镜护理液中聚季胺盐-1的含量,探讨护理液中其它成分对测定结果的影响。聚季铵盐-l与镁离子、染料丽春红S反应生成不溶性复合物,通过测量染料丽春红S吸光度的降低对聚季铵盐-l进行定量分析。检测波长为513 nm,聚季胺盐-1的质量浓度(X)在1.2~14.5μg/m L内与吸光度(Y)线性良好,线性方程为Y=0.061 7X–0.122 1,r~2=0.998 1。测定结果的相对标准偏差为1.1%(n=6),日间重复性为1.6%。样品3水平加标回收率为92.5%~99.9%。该法操作简单,方法稳定且准确,可作为角膜接触镜护理液中有效成分聚季胺盐-1质量控制的方法之一。     

A polarisation-independent blue-phase liquid crystal microlens using an optically hidden dielectric structure

A polarisation-independent blue-phase liquid crystal microlens using an optically hidden dielectric structure is proposed. In this design, the non-uniform electric field across the lens aperture is obtained by the modulation of the effective dielectric constant of an optical hidden layer. As the applied voltage varies from 0 to 150V_rms, the focal length of the lens can be tuned from ∞ to 16.6 mm. Simulation results show that this device has a parabolic-like profile and exhibits polarisation-independent property.     

Dosimetric studies of the eye lens using a new dosemeter – Surveys in interventional radiology departments

During interventional radiology (IR) and cardiology (IC) procedures, medical staff can receive high doses to their eye lenses. The Retrospective Evaluation of Lens Injuries and Dose study organized in Argentina in 2010 found incipient opacity in 50% of IC physicians and 41% of IC technicians/nurses. These results, added to the recommendations of the International Commission on Radiological Protection, which lowered their former occupational equivalent dose limit for the lens, led us to assess the eye lens dose, Hp(3), during interventional procedures.To this end, a new dosemeter was designed and calibrated at the National Atomic Energy Commission of Argentina to evaluate Hp(3). Personal dose equivalent (Hp(10)), and Hp(3) were assessed for 3 months in two IC and IR departments. An Alderson phantom was used to simulate monthly exposures of five occupational staff members.Hp(3) and Hp(10) were obtained monthly for 14 occupational staff members exposed to 121 IR and IC procedures. We concluded that the annual effective dose and Hp(3) were lower than 0.3 and 10 mSv, respectively and the average cumulative Hp(3) for working life was lower than 400 and 200 mSv for physicians and technicians/scrub nurse, respectively. An occupational annual dose constraint of 0.3 mSv was calculated.     

Coma compensation of o-ring driven liquid-filled lenses

The purpose of this study was to analyze the coma compensation of bi-convex o-ring driven liquid-filled lenses. In a previous study, the o-ring driven liquid-filled lens was composed of a base plate, a glass covered liquid container, an elastic membrane, an o-ring, a spring, and three hand-driven screws. The movement of the ring is used to control the focal length or the focus position. However, the o-ring driven liquid lens exhibited a coma effect when trying to use it to tilt the direction of light. To resolve this problem, in this study the bi-convex o-ring driven liquid-filled lens was constructed of two single o-ring driven liquid-filled lenses, and a coma compensation analysis of this new design is carried out. zemax software was used to construct the model, and the Zernike polynomials were used to estimate the compensation result. According to the simulation results, the following two actions could compensate for the initial coma aberration: (1) the same tilt direction of the front and back lenses; (2) increased the curvature of the back lens.     

Properties of efficient solution sets under addition of objectives

This paper addresses a general multicriteria optimization problem under various optimality principles. We investigate the behavior of the sets of Pareto and lexicographic optima when considering an additional objective.     

基于菲涅耳透镜开放光路天然气泄漏检测系统设计研究

天然气泄漏直接导致能源浪费和环境污染,造成重大经济损失。以可调谐半导体激光吸收光谱技术为基础的光学检测方法具有精度高、选择性强、响应速度快以及远距离遥测等优点,使其成为天然气站场以及天然气输运管道在线监测的理想方法。可调谐半导体激光吸收光谱与谐波探测相结合,设计了一套开放式长光程的用于天然气泄漏监测的实验系统。它以中心波长为1.65 μm的分布式反馈InGaAS激光器为光源,利用实心角反射器,在发射端以菲涅耳透镜为光学接收系统,把反射回来的光聚焦到InGaAs探测器。同时,在测量过程中,考虑到光强变化对浓度的影响,并通过归一化光强的方法进行消除,使光强波动引起的误差小于1%。在320 m的光程下模拟管道泄漏实验,系统的检测灵敏度为0.1(10-6体积比),根据光学系统收光效率以及探测器的可探测性能进行分析的最小光强,计算得到该系统可探测的光程可达2 000 m,证明完全满足天然气泄漏检测的需求。     

目标函数设置对放疗逆向计划多目标优化过程的影响

目前放疗逆向计划中常用的目标函数有两种:基于剂量分布的目标函数和基于剂量．体积直方图（DVH）的目标函数。实际系统都基于单目标优化算法进行,不考虑逆向计划的多目标性。在Pareto多目标优化理论的基础上,研究逆向计划的目标函数设置问题,比较基于剂量分布的目标函数和基于DVH的目标函数对多目标优化过程的影响,包括优化时间、收敛性和存在的问题等,为逆向计划过程中多目标优化目标函数的设置提供依据。There are two kinds of objective functions in radiotherapy inverse planning: dose distribution-based and Dose-Volume Histogram （DVH）-based functions. The treatment planning in our days is still a trial and error process because the multi-objective problem is solved by transforming it into a single objective problem using a specific set of weights for each object. This work investigates the problem of objective function setting based on Pareto multi-optimization theory, and compares the effect on multi-objective inverse planning of those two kinds of objective functions including calculation time, converge speed, etc. The basis of objective function setting on inverse planning is discussed.     

变焦距镜头初始结构智能化设计方法

给出一个智能化专家系统,实现了对变焦距镜头初始结构参数的自动设计,包括对任一变焦方式的高斯光学参数的计算,以及对各组元结构参数的自动生成和优化.