Study On Rapid Measurement Of Infrared Spectra Of Liquid Fertilizer Components

Integration of water and fertilizer is one of the important trends in the development of modern agriculture.However,how to achieve rapid detection of effective nutrients and harmful substances in irrigation water has always been an intractable problem.The traditional method can accurately obtain irrigation water components by laboratory analysis after sampling.However,because of the complexity of the sample preparation process,the laboratory analysis method is time-consuming and laborious,it is easy to cause secondary pollution,and can not achieve rapid and on-line detection.In order to solve this problem,a new type of miniaturized and portable near infrared spectrum detection equipment,which based on micro-electro-mechanical(MEMS)technology,was realize rapid detection of effective nutrient content of liquid fertilizer.In addition,aiming at the problem that the bacterial colony in organic liquid fertilizer exceeded the standard,the low concentration bacterial colony in water was detected by the method of infrared spectrum enhancement.The main part of this study is divided into two parts.The first part is the development of a portable near-infrared spectrum detection device based on micro-electro-mechanical(MEMS)technology.By using the novel micro-electromechanical-Fabry-Perot(MEMS-FPI)near-infrared spectrum detector,the volume and weight of the device are effectively reduced,and the driving module of the detector is designed.By simplifying the design of the optical path,the light source with small volume and good stability and the driving circuit are used,and detection result is obtained.In the second part,trace harmful substances in irrigation water such as bacteria,the infrared spectrum enhancement method is explored,and successfully detecte bacterial colony number in water.The bacterial colony number in aqueous solution represented by Escherichia coli was detected by super-hydrophobic enhanced attenuated total reflection method.Germ was successfully detected at the concentration as low as 500 CFU/ML.This method greatly improves the detection ability of germ in water and provides a new idea for the rapid determination of trace harmful substances content in water by infrared spectroscopy.The portable near infrared(NIR)equipment for the determination of available nutrients in liquid fertilizer is an important part of precision agricultural water and fertilizer integration technology.This kind of equipment can quickly detect the available nutrients in liquid fertilizer in the field,which can be used as a guide for rational fertilization.It is of great significance to improve soil environment,reduce the use of fertilizer and reduce waste of water resources.The ultra-hydrophobic infrared enhancement method can be used to detect the bacteria with lower concentration in water quickly,which has reference significance for the detection of micro-harmful substances in liquid fertilizer.