Research On The Technology Of Measuring The Content Of Sodium And Potassium By Flame Photometric Method

Sodium and potassium are two kinds of constant elements.They have an important role in many fields, such as soil analysis, human medicine, agricultural fertilizer, medicine industry, etc.. It is usually required to accurately measure the content of these two elements to determine whether they are within the standard range.In this thesis, the method of measuring content of sodium and potassium was deeply studied. Firstly, the shortcomings and deficiencies of the current detection methods were compared and analyzed by researching on a large number of documents.The flame reaction characteristics and atomic emission spectral characteristics of sodium and potassium was studied, and the relationship between the silicon photocell photocurrent intensity and light intensity was analyzed. Moreover the atomic emission spectrometry was deeply researched, and the mathematical model of the relationship between intensity of emission and concentration of analyte was established. Based on the study above, the research method of this topic--Flame photometric method was put forward, and the flow chart of the flame photometric method was designed.Secondly, according to the mathematical model and the algorithm deduced in this thesis, the whole scheme design of the measuring system was completed by using the principle of flame photometric method. After the photo-electric conversion module of sodium and potassium, the gas path module, the control module, the display module, the signal input module, the data output module and the preparation of software were completed, the development of human-computer interaction interface of PC and measurement system based on MSP430f149 microprocessor were completed. With the experimental platform set up and whole measurement system installed, sample liquid was gasified, light intensity signal was converted into digital signal, sodium and potassium were measured at the same time, data was displayed dynamically on LCD, historical data could be queried and cleared, data could be transferred to PC and printed, the program of measurement system was updated online. The interactive interface of PC was designed by using Lab VIEW. Data could be sent from measurement system to PC and be automatically displayed and stored, the standard curve was also generated and displayed on PC.Lastly, after a large number of repeated measurement experiments, the results show that the proposed method is convenient, fast and accurate, and the measurement system has advantages, such as easy operation, high intelligence, functional diversification, stable operation, low cost and so on.