固液溶解度激光动态检测系统

发布时间：2018-04-11 19:20

  本文选题：半导体激光器恒功率 + 双闭环　； 参考：《长安大学》2017年硕士论文

【摘要】：溶解度是反映试剂溶解性的重要参数,固液溶解度参数广泛应用于医学、化学、工业生产等多个领域,然而目前已有的固液溶解度参数测量方法还不够成熟和完善,传统方法如平衡法、动态法等测定溶液溶解平衡终点都要人眼进行目测,其缺点是由于人为因素的加入导致误差大且效率低下,并且只能进行静态测量。针对传统方法存在的缺陷设计一种高精度、高效率的自动化动态溶解度检测系统无疑对化学、医学、工业生产的溶解度实验具有重要的现实意义。为此,基于Lambert溶液光学吸收定律,本文提出了一种采用稳定的激光光源照射、灵敏的光电二极管探测、计算机动态采集温度—时间和光强—时间的自动化动态高效溶解度检测系统。围绕设计工作中的核心和关键,本文的研究内容如下:首先,分析了Lambert定律光学吸收原理的使用依据和范围以及造成Lambert定律偏离因素,针对影响系统测量精度的核心因素,研究了半导体激光器恒功率控制算法,设计了双闭环激光器恒功率控制模型,提出基于神经网络PI控制的激光器恒功率控制算法,并通过仿真实验验证了算法的有效性。本部分设计了以PIC单片机为核心的激光器恒功率控制硬件电路,算法实现程序,最终实现了功率波动在2.4%的稳定控制精度。接着,针对系统对激光光强、温度检测系统的要求,研究并设计了接收系统硬件电路和软件程序。接收电路采用灵敏的光电二极管和高精度热电阻温度传感器构成光强、温度检测实时电路,重点分析和设计了光电转换电路的信号调理,并通过仿真实验进行了验证,最终实现了信号的高精度采集和传输,提高了系统的自动化程度和测量精度。最后,构建了系统的整体原理样机,并在陕师大化学实验室进行了系统实测实验。实验采用10~50℃之间的KCI-H2O体系为标准体系验证系统的可行性,结果显示,半导体激光器的输出光功率稳定,测得KCI-H2O体系中KCI溶解度误差为±0.005kg,与设计要求值吻合良好。该检测系统可以克服传统检测方法的不足,大大提高了溶解度检测的精度和效率,满足了不同行业的需求。
[Abstract]:Solubility is an important parameter reflecting the solubility of reagents. Solid-liquid solubility parameters are widely used in many fields, such as medicine, chemistry, industrial production, etc.The traditional methods, such as equilibrium method and dynamic method, all need human eyes to observe the end point of solution dissolution equilibrium. The disadvantage of this method is that the error is large and the efficiency is low due to the addition of human factors, and only static measurement can be carried out.Aiming at the defects of traditional methods, it is of great practical significance to design an automatic dynamic solubility detection system with high accuracy and efficiency for chemical, medical and industrial experiments.In this paper, based on the optical absorption law of Lambert solution, a sensitive photodiode detector with a stable laser light source is proposed.Automatic dynamic and efficient solubility measurement system for temperature-time and light intensity-time acquisition by computer.The research contents of this paper are as follows: firstly, the basis and scope of the optical absorption principle of Lambert's law and the factors causing the deviation of Lambert's law are analyzed, and the key factors that affect the measurement accuracy of the system are analyzed.In this paper, the constant power control algorithm of semiconductor laser is studied, the model of double closed loop laser constant power control is designed, and the algorithm of constant power control based on neural network Pi control is proposed, and the validity of the algorithm is verified by simulation experiment.In this part, the hardware circuit of laser constant power control based on PIC single chip microcomputer is designed. The algorithm realizes the program, and finally realizes the stable control precision of 2.4% power fluctuation.Then, the hardware circuit and software program of the receiving system are studied and designed according to the requirements of the system for laser light intensity and temperature detection system.The receiving circuit is composed of sensitive photodiode and high precision thermistor temperature sensor. The real time circuit of temperature detection is used. The signal conditioning of photoelectric conversion circuit is analyzed and designed, and verified by simulation experiment.Finally, the high-precision acquisition and transmission of signals are realized, and the automation and measurement accuracy of the system are improved.Finally, the whole principle prototype of the system is constructed, and the system experiment is carried out in the chemical laboratory of Shaanxi normal University.The feasibility of the system is verified by using the KCI-H2O system between 10 鈩，

本文编号：1737330