【作者】 杜亚尊；

【导师】 钱东平；

【作者基本信息】 河北农业大学 ， 农业机械化工程， 2008， 硕士

【摘要】 水是自然资源的重要组成部分,是所有生物的结构组成和生命活动的主要物质基础,对于人类和生物的生存来说具有决定性的意义。然而,随着全球经济、人口的高速增长,水资源短缺己成为人类生活中的显著问题,加上大量废弃的生活污水和生产污废水的任意排放,使有限的水资源更加紧张。油类物质(石油类物质和动植物油)是水和土壤中的一项重要的污染源,它不仅给人类的身体健康带来极大的危害,而且使水质恶化,严重破坏水体的生态平衡。因此,检测水中油含量是控制油污染,掌握水质变化,保护水资源的必不可缺的手段。关于水中油含量的检测,传统的方法是利用单一的分光光度计法来测量,测量结果再经换算才可得到被测物质的浓度,这种方法操作过程繁琐,容易引入误差,且不能现场作业。通过本课题的研究,探索出一套适合我国国情的水质油污染现场检测技术和检测设备,它能方便地检测水中含油量,且其体积小巧,携带方便。本仪器以非分散红外光度法为测定依据,其测油的基本原理是基于光学原理中的朗伯—比尔定律。本文从测油仪的光源系统、样品系统、分光系统、检测系统和计算机系统等五大系统全面介绍了仪器的设计结构,并进行了详细的理论分析,通过软件实现了数据的采集、处理、显示、打印和通讯等功能。该仪器中自然光的干扰是遇到的主要困难,在了解近红外光谱分析仪中的信号和噪声特点后,采用切光的办法来对光信号进行调制可有效的克服这一问题,使信号变得容易处理,而通过采用相敏检测的方法又可大大提高信噪比。文章系统的介绍了弱信号的提取方法,解决了信号提取困难的问题,并给出了实际可行的电路。另外,基于AT89C52单片机的计算机系统中是该仪器的核心部分,将由检测系统转换来的电信号换算成油类物质的浓度,并显示、打印出来。特有的数据存储功能,使仪器掉电后数据不丢失。系统中设计了看门狗电路,防止由于程序跑飞和电源故障引起的工作不正常。本仪器既可以与PC机联用也可以脱离PC机单独使用。操作软件功能强大,具有仪器性能自检及在线帮助功能,可实现网上服务。本课题是针对我国水体的油污染,利用非分散红外光度法技术,设计出适于野外作业的便携式测油仪。利用此仪器,可以检测出水中矿物油和动植物油的污染物含量,还可用于有机试剂纯度检测及含各种不同C-H键有机物总量和分量的测量。本测油仪采用了调节方便、频率精确的光源调制系统和相关检测技术,具有较高的灵敏度和稳定性,体积小适于野外现场使用。更多还原

【Abstract】 The water is the important composing of natural resource and is the main material foundation of the biological structure composition and human activity, so it has the decisive significance for human and biological survival. However, with the global economy and the population growing greatly, the scarcity of water resource becomes a remarkable question in the human life, even the random drainage of waster water in human living and production, which causes the limited water resource to be more intense. Oil matter which contains petroleum matter and propagation oil matter always are important source of pollution in water and soil. It not only brings serious harm to human’s health, but also causes the water quality to be worse and destroys the ecological balance of water badly. Therefore detecting the oil content in water is the indispensable measure to control the oil pollution, command the change of water quality and protect the water resource.For the oil detecting in water, the traditional method is that using the spectrophotometer to measure, then the measurement results are converted into density of the measured material, so the operating process of this method is tedious and easy to introduce the error, and it can’t be operated in field. Through the research of this topic, we explores a suit of detecting facility and scene examination technology, it can detect the oil content in water conveniently, and its volume is exquisite to carry conveniently.This instrument is based on the non-dispersed infrared spectrophotometry and its basic detecting principle is Lambert—Bill law. This article expatiate the design structure of the instrument from the five aspects including lamp-house system, sample system, light dispersion system, detecting system and computer system, and make detailed theoretical analysis of each part. It realizes the functions such as data gathering, processing, demonstration, printing and communication through the software. In this instrument, the disturbance of natural light is the main difficulty, which is solved by modulating optical signal using light-cutting after understanding the characteristic of signal and noise in the infrared spectrum analyzer, then the signal becomes easy to be disposed, and uses the sensitive examination method to enhance the ratio of signal-to-noise greatly. The article introduces the extraction method of weak signals systemically and solves the problem of signal extraction, and has given the feasible electric circuit. Moreover, the AT89C52 monolithic integrated circuit system is the core part of this instrument, by which the electrical signal that transformed by the infrared sensor is converted into the density of oil matter, and then the result is showed and printed. The unique data storage function makes the data not lose when electricity of the instrument turns off. This system has watch-dog circuit so it prevents work abnormality caused by program fleet and power fault. This instrument can be used with PC or be separated from the PC, the function of the operation software is formidable, it not only has the function of self-checking and on-line assistance, but also can realize the on-line service.In view of oil pollution of water in our country, this topic designs an oil mensuration instrument which is portable and suiting fieldwork using the technique of non-disperse infrared spectrophotometry. The oil instrument can detect the total oil content of the water; moreover, it can be used for detecting the organic reagent and the different capacity of C-H in organic substance. The instrument adopts the lamp-house modulating system, which adjusted conveniently and has an exact frequency. In a word, it has a high sensitiveness and stability and it can be used in open country for its small volume.更多还原