阅读说明：本技术 一种液体浓度检测方法 (Liquid concentration detection method ) 是由 赵然 鲁骎 其他发明人请求不公开姓名 于 2018-05-29 设计创作，主要内容包括：本发明提供一种液体浓度检测方法,将已知浓度的某种液体用显色剂进行显色反应,并对显色反应的结果进行拍摄采集,将采集到的图片分解为一个RGB格式的像素矩阵,每个像素点位包含红绿蓝三个不同颜色的色彩强度值。针对不同颜色,分别求得图片上所有对应像素点位色彩强度的均值,会得到三个不同的平均值。通过重复该方法,并对得到的三种色彩强度均值进行拟合,选择出一种拟合度最高即决定系数R<Sup>2</Sup>最趋向于1时的一条线,即为一条该种液体的浓度与显色反应色彩强度的标准曲线。通过将待测液体在显色反应之后的结果求得的色彩强度平均值代入所述标准曲线,就能得出所对应的浓度。本发明操作简单、成本低廉、检测精度准确,是一种简单、有效的检测方法。(the invention provides a liquid concentration detection method, which comprises the steps of carrying out color development reaction on certain liquid with known concentration by using a color developing agent, shooting and collecting the result of the color development reaction, decomposing the collected picture into a pixel matrix in an RGB format, wherein each pixel point comprises three color intensity values of red, green and blue with different colors. And respectively solving the average value of the color intensity of all corresponding pixel points on the picture aiming at different colors, and obtaining three different average values. By repeating the method and fitting the obtained three color intensity mean values, a line with the highest fitting degree, namely the determination coefficient R2, which is the most trend to 1 is selected, namely a standard curve of the concentration of the liquid and the color intensity of the color reaction. And substituting the average value of the color intensity obtained by the result of the liquid to be detected after the color reaction into the standard curve to obtain the corresponding concentration. The invention has simple operation, low cost and accurate detection precision, and is a simple and effective detection method.)

1. a liquid concentration detection method is characterized by comprising the following steps:

Step 1: making a standard curve of the concentration of the known liquid and the color intensity of the color development reaction;

Step 1.1: carrying out color reaction on the known liquid by adopting a color reagent;

Step 1.2: shooting and collecting a color reaction result, decomposing the collected picture into a pixel matrix in an RGB format, wherein each pixel point comprises three color intensity values of red, green and blue with different colors; respectively solving the average value of the color intensity of all corresponding pixel points on the picture aiming at different colors to obtain three different average values;

Step 1.3: repeating the operations from the step 1.1 to the step 1.2 on the known liquid with various concentrations, fitting the obtained three color intensity mean values, and selecting a line with the highest fitting degree, namely a standard curve of the concentration of the liquid and the color intensity of the color development reaction;

Step 2: and (3) calculating the color intensity of the liquid to be measured after the color reaction by the method in the step 1.2, and substituting the calculated color intensity into the standard curve to obtain the corresponding liquid concentration.

2. The method according to claim 1, wherein the known liquid is a nitrite solution, a solution containing ammonium ions, and a solution containing phosphate ions; the chromogenic reagent is griess reagent, Nashi reagent and ammonium molybdate-ascorbic acid solution which respectively correspond to the solutions.

3. The method as claimed in claim 1, wherein the detection limit of the method is that the nitrite concentration is in the range of 0-0.6mg/L, the ammonia radical ion concentration is in the range of 1-20mg/L, and the phosphate radical ion concentration is in the range of 0.8-5 mg/L.

4. The method as claimed in claim 1, wherein the determination coefficient R2 is most towards 1 when the fitting degree is highest.

5. The method as claimed in claim 1, wherein the number of repetitions of steps 1.1 to 1.2 for known liquids of various concentrations is 5 or more.

6. the method according to claim 2, wherein the Griess reagent contains 10 ml phosphoric acid, 40 g sulfanilamide, 2 g N- (1-naphthyl) -ethylenediamine hydrochloride per liter, and the rest is deionized water; the ratio of Griess reagent to test sample is 1 to 50.

7. The method according to claim 2, wherein said NasLord reagent contains 160 g sodium hydroxide, 173 g mercuric potassium iodide, and the rest is deionized water per liter; the ratio of the Nassner reagent to the sample to be tested is 1 to 50.

8. The method according to claim 2, wherein the ammonium molybdate-ascorbic acid solution comprises a molybdate reagent and an ascorbic acid solution, and the molybdate reagent comprises 300 ml of ascorbic acid, 26 g of ammonium molybdate, 0.7 g of antimony potassium tartrate and the balance of deionized water per liter of the ammonium molybdate-ascorbic acid solution; the ascorbic acid solution is 100 grams per liter of aqueous solution; the two reagents need to be mixed with the sample at the same time, and the proportion is as follows: sample preparation: ascorbic acid: ammonium molybdate =25:1: 2.

Technical Field

The invention relates to a detection method, in particular to a liquid concentration detection method based on a color reaction, and belongs to the technical field of chemical component detection.

Background

The nature of the color reaction is a process in which one or a group of chemical reactions occur between the liquid to be measured and the reagent, producing another new substance exhibiting a specific color. At present, the determination of the concentration range of a liquid to be detected through a color reaction is one of the commonly used methods in the fields of biology, chemistry and the like, and for example, the detection of fat, protein and sugar, the detection of nitrite, ammonium ions and phosphate ions and the like are very common detection objects. Compared with the existing chromatography, electrophoresis, spectrophotometry and the like, the method for detecting the liquid concentration by the result of the color reaction is simple to operate, has lower requirements on personnel and instruments, and has much lower maintenance cost and detection cost. However, there is a problem in detecting the concentration of the liquid based on the color reaction, for example, the result is defined by using a colorimetric kappa equivalent method, which has a large error and may cause an artificial influence on the result.

disclosure of Invention

The invention aims to solve the problems that the liquid concentration detection method based on the color reaction is simple to operate, low in cost and excellent in performance, has accurate detection precision, is simple to operate and low in cost, and is a simple and effective detection method.

The invention mainly solves the technical problems through the following technical scheme:

The liquid concentration detection method provided by the invention can automatically compare the liquid to be detected with the concentration standard curve and generate a result. The known solution and the color reagent are controlled by a computer to perform fusion reaction, and the color reaction result is shot by a camera and uploaded to the computer for processing. The method comprises the steps of carrying out color reaction on certain liquid with known concentration and a color reagent, shooting and collecting the result of the color reaction, decomposing the collected picture into a pixel matrix in an RGB format, wherein each pixel point comprises three color intensity values of red, green and blue with different colors. And respectively solving the average value of the color intensity of all corresponding pixel points on the picture aiming at different colors, and obtaining three different average values. By repeating the method and fitting the obtained three color intensity mean values, a line with the highest fitting degree, namely the determination coefficient R2, which is the most trend to 1 is selected, namely a standard curve of the concentration of the liquid and the color intensity of the color reaction. And substituting the average value of the color intensity obtained by the result of the liquid to be detected after the color reaction into the standard curve to obtain the corresponding concentration. Because the concentration of the liquid to be measured can be accurately obtained by the method through automatic acquisition, calculation and comparison of a computer.

step 1: making a standard curve of the concentration of the known liquid and the color intensity of the color development reaction;

step 1.1: carrying out color reaction on the known liquid by adopting a color reagent;

Step 1.2: and shooting and collecting a color reaction result, decomposing the collected picture into a pixel matrix in an RGB format, wherein each pixel point comprises three color intensity values of red, green and blue with different colors. And respectively solving the average value of the color intensity of all corresponding pixel points on the picture aiming at different colors, and obtaining three different average values.

step 1.3: and (3) repeating the operations from the step 1.1 to the step 1.2 for known liquids with various concentrations, fitting the obtained three color intensity mean values, and selecting a line with the highest fitting degree, namely when the determination coefficient R2 is most trending to 1, namely a standard curve of the concentration and the color intensity of the color reaction of the liquid. In the process of repeating the operations from step 1.1 to step 1.2 for known liquids of various concentrations, the number of repetitions must be 5 or more.

Step 2: and (3) calculating the color intensity of the liquid to be measured after the color reaction by the method in the step 1.2, and substituting the calculated color intensity into the standard curve to obtain the corresponding liquid concentration.

The known liquid is nitrite solution, solution containing ammonia ions and solution containing phosphate ions; the chromogenic reagent is a Griess reagent, a Nashi reagent and an ammonium molybdate-ascorbic acid solution which respectively correspond to the solutions.

The Griess reagent contains 10 ml of phosphoric acid, 40 g of sulfanilamide, 2 g of N- (1-naphthyl) -ethylenediamine hydrochloride and the balance of deionized water per liter, and the ratio of the Griess reagent to a sample to be detected is 1: 50.

The NasLei reagent contains 160 g of sodium hydroxide, 173 g of mercury potassium iodide and the balance of deionized water per liter. The ratio of the Nassner reagent to the sample to be tested is 1 to 50.

The ammonium molybdate-ascorbic acid solution consists of a molybdate reagent and an ascorbic acid solution, wherein in each liter of the ammonium molybdate-ascorbic acid solution, the molybdate reagent contains 300 milliliters of ascorbic acid, 26 grams of ammonium molybdate, 0.7 gram of antimony potassium tartrate and the balance of deionized water. The ascorbic acid solution was 100 grams per liter of aqueous solution. The two reagents need to be mixed with the sample at the same time, and the proportion is as follows: sample preparation: ascorbic acid: ammonium molybdate =25:1: 2.

the detection limit of the method is that the concentration of nitrite is in the range of 0-0.6mg/L, the concentration of ammonia radical ions is in the range of 1-20mg/L, and the concentration of phosphate radical ions is in the range of 0.8-5 mg/L.

Compared with the prior art, the liquid concentration detection method based on the color reaction ensures the detection precision; secondary damage to the environment and the analyst is avoided; meanwhile, the effects of real-time monitoring and autonomous detection can be realized by means of a computer; the method is low in cost and easy to maintain, and is a detection method which is worth popularizing.

Drawings

FIG. 1 is a concentration standard curve of the nitrite-Griess reagent detection method of the present invention.

FIG. 2 is a concentration standard curve of the detection method of the invention.

FIG. 3 is a concentration calibration curve of the method for detecting a phosphate ion-ammonium molybdate-ascorbic acid solution according to the present invention.

Detailed Description

The technical scheme of the invention is further explained by combining the attached drawings and the specific embodiment, the liquid concentration detection method based on the color reaction provided by the invention controls the fusion reaction of the known solution and the color reagent through a computer, and captures the color reaction result through a camera and uploads the color reaction result to the computer for processing. Certain liquid with known concentration is subjected to color reaction through a color reagent, the result of the color reaction is shot and collected, the collected picture is decomposed into a pixel matrix in an RGB format, and each pixel point comprises three color intensity values of red, green and blue with different colors. And respectively solving the average value of the color intensity of all corresponding pixel points on the picture aiming at different colors, and obtaining three different average values. By repeating the method and fitting the obtained three color intensity mean values, a line with the highest fitting degree, namely the determination coefficient R2, which is the most trend to 1 is selected, namely a standard curve of the concentration of the liquid and the color intensity of the color reaction. And substituting the average value of the color intensity obtained by the result of the liquid to be detected after the color reaction into the standard curve to obtain the corresponding concentration. Because the sodium nitrite concentration of the liquid to be measured can be accurately obtained by the method through automatic acquisition, calculation and comparison of a computer.

The method comprises the following specific steps:

step 1: making a standard curve of the concentration of the known liquid and the color intensity of the color development reaction;

Step 1.1: carrying out color reaction on the known liquid by adopting a color reagent;

Step 1.2: and shooting and collecting a color reaction result, decomposing the collected picture into a pixel matrix in an RGB format, wherein each pixel point comprises three color intensity values of red, green and blue with different colors. And respectively solving the average value of the color intensity of all corresponding pixel points on the picture aiming at different colors, and obtaining three different average values.

Step 1.3: and (3) repeating the operations from the step 1.1 to the step 1.2 for known liquids with various concentrations, fitting the obtained three color intensity mean values, and selecting a line with the highest fitting degree, namely when the determination coefficient R2 is most trending to 1, namely a standard curve of the concentration and the color intensity of the color reaction of the liquid. In the process of repeating the operations from step 1.1 to step 1.2 for known liquids of various concentrations, the number of repetitions must be 5 or more.

Step 2: and (3) calculating the color intensity of the liquid to be measured after the color reaction by the method in the step 1.2, and substituting the calculated color intensity into the standard curve to obtain the corresponding liquid concentration.

The known liquid is nitrite solution, solution containing ammonia ions and solution containing phosphate ions; the chromogenic reagent is griess reagent, Nashi reagent and ammonium molybdate-ascorbic acid solution which respectively correspond to the solutions.

The griess reagent contains 10 ml of phosphoric acid, 40 g of sulfanilamide, 2 g of N- (1-naphthyl) -ethylenediamine hydrochloride and the balance of deionized water per liter, and the ratio of the griess reagent to a sample to be detected is 1: 50.

The NasLei reagent contains 160 g of sodium hydroxide, 173 g of mercury potassium iodide and the balance of deionized water per liter. The ratio of the Nassner reagent to the sample to be tested is 1 to 50.

The ammonium molybdate-ascorbic acid solution consists of a molybdate reagent and an ascorbic acid solution, wherein in each liter of the ammonium molybdate-ascorbic acid solution, the molybdate reagent contains 300 milliliters of ascorbic acid, 26 grams of ammonium molybdate, 0.7 gram of antimony potassium tartrate and the balance of deionized water. The ascorbic acid solution was 100 grams per liter of aqueous solution. The two reagents need to be mixed with the sample at the same time, and the proportion is as follows: sample preparation: ascorbic acid: ammonium molybdate =25:1: 2.

the detection limit of the method is that the concentration of nitrite is in the range of 0-0.6mg/L, the concentration of ammonia radical ions is in the range of 1-20mg/L, and the concentration of phosphate radical ions is in the range of 0.8-5 mg/L.

And fitting the obtained data by using different forms of equations according to needs, and setting the data form of the obtained standard curve as y = y (x), wherein x represents a measured color intensity mean value, and y is the corresponding original measured concentration. When the obtained color intensity mean fitting degree is the highest, namely the determination coefficient R2 is the most trend to 1, the fitting result is a standard curve of the concentration of the liquid and the color intensity of the color reaction. Wherein, various fitting modes can be as follows:

Firstly, linear fitting:

(1) Let the linear fit equation be y '= ax + b, y' be the known solution concentration calculated by the equation. a and b are constants.

(2) The sum of the squared errors between the resulting known solution concentration y' values and the original measured concentration y values is calculated by randomly extracting the a values and b values into a linear fit formula.

(3) With the help of mathematical software such as excel or matlab, the numerical values of a and b corresponding to the time when the sum of the squares of the errors is minimum can be found; the equation for the standard curve can be derived.

II, logarithmic fitting:

(1) Let the formula of the logarithmic fit be y' = a × ln (x) + b, where a, b are constants.

(2) the sum of the squared errors between the resulting known solution concentration y' values and the original measured concentration y values is calculated by randomly extracting the values of a and b into a log fit equation.

(3) With the help of mathematical software such as excel or matlab, the numerical values of a and b corresponding to the time when the sum of the squares of the errors is minimum can be found; the equation for the standard curve can be derived.

Thirdly, exponential fitting:

(1) Let the formula of exponential fit be y' = a ebx, where a, b are constants

(2) The sum of the squared errors between the resulting known solution concentration y' value and the original measured concentration y value is calculated by randomly extracting the a value and the b value into an exponential fit formula.

(3) With the help of mathematical software such as excel or matlab, the numerical values of a and b corresponding to the time when the sum of the squares of the errors is minimum can be found; the equation for the standard curve can be derived.

Fourth, power fitting:

(1) Let the formula of the power fitting be y' = a x xb, where a, b are constants

(2) The sum of the squared errors between the resulting known solution concentration y' value and the original measured concentration y value is calculated by randomly extracting the a value and the b value into a power fit formula.

(3) With the help of mathematical software such as excel or matlab, the numerical values of a and b corresponding to the time when the sum of the squares of the errors is minimum can be found; the equation for the standard curve can be derived.