Method for jointly testing turbidity and oxygen consumption of feather down

Abstract

The invention relates to the technical field of feather down turbidity and oxygen consumption combined testing, and discloses a feather down turbidity and oxygen consumption combined testing method, which comprises the following steps: 1, preparing about 1000ml of sample liquid according to a GB / T 10288-2016 Down and Feather Inspection Method 5.4 oxygen consumption pretreatment method; 2, 100 ml of the sample liquid is taken and injected into a measuring vessel in a tester, the measuring vessel is 10 cm long, 1 cm wide and 15 cm high, the upper portion of the measuring vessel is open, the bottom face, the left side and the right side of the measuring vessel are transparent, the front side and the rear side of the measuring vessel are not transparent, the measuring vessel is arranged on a linear sliding rail base, and the linear sliding rail base is driven by a motor to move front and back to shake. The absorbance of a sample solution after a potassium permanganate standard solution is dropwise added is measured by adopting a spectrophotometric method, the concentration of residual potassium permanganate is obtained by contrasting with a standard curve, and then the oxygen consumption of the down feather is obtained by adopting a differential method. According to the method, subjective end point judgment of measurement personnel in a current standard method is avoided, and especially when a sample has a color, the difficulty of end point judgment can be effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of combined testing of the turbidity and oxygen consumption of down and feathers, and in particular to a method for combined testing of the turbidity and oxygen consumption of down and feathers. Background Art

[0002] The current standards for detecting the turbidity of down and feathers mainly include the Chinese standard GB / T 10288—2016 "Inspection Methods for Down and Feathers". Internationally, the standards related to the turbidity inspection of down and feathers include the IDFB Testing Regulations 2020 "Testing Regulations for Down and Feathers" of the International Down and Feather Bureau, the EU standard EN1164:1999 "Testing Methods for Down and Feathers - Determination of the Turbidity of Aqueous Extracts", and the Japanese standard JIS L1903—2017 "Testing Methods for Feathers". The Chinese standard also adds Method B using a special turbidimeter, and there is also a method using a turbidimeter in the IDFB testing method. The principles of the two turbidimeter methods are different. The Chinese method measures the absorbance of light passing through the sample solution, establishes the functional relationship between the absorbance and the results of the visual method, and indirectly determines the turbidity. The IDFB method uses a scattered light type turbidimeter to establish the relationship between the scattered light intensity and the turbidity, with the unit of NTU. However, the optical paths of both turbidimeters are perpendicular to the precipitation direction of the sample solution and also perpendicular to the observation direction of the human eye when using the visual method. The precipitation of the sample solution makes the repeatability of absorbance measurement poor.

[0003] At present, the detection methods for the oxygen consumption of down and feathers include the Chinese standard GB / T 10288-2016 "Inspection Methods for Down and Feathers", the IDFB Testing Regulations 2020 "Testing Regulations for Down and Feathers" of the International Down and Feather Bureau, the EU standard EN1162:1996 "Testing Methods for Down and Feathers - Determination of Oxygen Consumption Index", and the Japanese standard JIS L 1903:2017 "Testing Methods for Feathers". The basic principles of these methods are the same, that is, titrating the oscillating filtrate of down and feathers with potassium permanganate solution, and calculating the oxygen consumption by measuring the amount of potassium permanganate solution used. However, this method has the following problems: when the color of the sample is slightly lighter or darker than the blank sample, when there is interference from impurities, and due to the subjectivity of the human eye, it is difficult to judge whether the color of the sample is the same as that of the blank sample, resulting in problems such as low test result accuracy and large data fluctuations.

[0004] This case is proposed to solve or improve the shortcomings or deficiencies of the existing technology. Summary of the Invention

[0005] The present invention is achieved by adopting the following technical solutions:

[0006] A method for combined testing of the turbidity and oxygen consumption of down and feathers, comprising the following steps:

[0007] Step 1: Prepare about 1000 ml of sample solution according to the pretreatment method of oxygen consumption in 5.4 of GB / T 10288-2016 "Inspection Methods for Down and Feather".

[0008] Step 2: Pour 100 ml of the sample solution into the measuring dish in the tester. The above-mentioned measuring dish is 10 cm long, 1 cm wide, and 15 cm high, with an open top, a transparent bottom and left and right sides, and opaque front and back sides. The material is quartz. (This measuring dish can be regarded as a cuvette of a spectrophotometer. Usually, quartz material is used, and optical glass material can also be used. The measuring dish made of quartz material has high hardness and strong wear resistance). The above-mentioned measuring dish is placed on the linear slide rail base and shaken by driving the linear slide rail base to move back and forth by a motor.

[0009] Step 3: Then, a composite light of (400 - 700) nm is vertically incident from the bottom of the measuring dish. The detector is above the measuring dish. Measure the absorbance of the sample solution, and make an absorbance-visual value working curve for different sample solutions. The above-mentioned visual value is the turbidity value measured by the method of 5.5.3.1A (visual method) in GB / T10288-2016, with the unit of mm. Fit the regression equation of the absorbance-visual value working curve, and input the absorbance obtained by the above method into the regression equation to obtain the turbidity value of the sample.

[0010] Step 4: Add 100 ml of tertiary water and 2 ml of 3 mol / L sulfuric acid aqueous solution to the above-mentioned measuring dish. The motor drives the measuring dish to move back and forth to mix the sample solution evenly. Gradually add 0.020 mol / L potassium permanganate standard solution drop by drop. When 0.020 ml, 0.080 ml, 0.160 ml, 0.200 ml, and 0.300 ml of the above-mentioned potassium permanganate standard solution are added respectively, the measuring dish moves back and forth and shakes for 1 min. Then, 525 nm visible light is vertically incident from the right side of the measuring dish, and the detector is correspondingly arranged on the left side of the measuring dish. Measure the absorbance of the test solution and establish a working curve of absorbance and the volume of potassium permanganate standard solution, and fit the regression equation:

[0011] A = 0.3761V - 0.00402 (Equation 1)

[0012] Where: A is the absorbance,

[0013] V is the volume of the potassium permanganate standard solution added drop by drop, with the unit of ml.

[0014] Step 5: Add 100 ml of the sample solution and 2 ml of 3 mol / L sulfuric acid aqueous solution to the above-mentioned measuring dish. The measuring dish moves back and forth to mix the sample solution evenly, and measure the absorbance A of the sample solution by the method in Step 4. 杂Add 0.200 ml of 0.020 mol / L potassium permanganate standard solution drop by drop. After moving the measuring dish back and forth and shaking for 1 minute, measure the absorbance A of the sample solution according to the method in the third step. 样 A = A 样 - A 杂 , Substitute A into Equation (1) to obtain V, then the oxygen consumption of the sample = (0.2 - V) * 80, with the unit of mg / 100 g.

[0015] The regression equation of the absorbance-visual value working curve and the regression equation of the absorbance-potassium permanganate standard solution volume working curve for daily detection can be prepared in advance and can be reused within a certain period of time. In this way, the turbidity and oxygen consumption of the feather and down can be measured quickly and accurately.

[0016] The advantages and positive effects of the present invention are:

[0017] 1. Adopting a vertical optical path design, different from the horizontal optical path design of the current standard turbidimeter, it improves the fluctuation of the test results caused by the sedimentation of the sample solution and enhances the measurement precision.

[0018] 2. By measuring the absorbance of the sample solution after adding the potassium permanganate standard solution using the photometric method, the concentration of the remaining potassium permanganate is obtained by comparing with the standard curve, and then the oxygen consumption of the down is obtained by the difference method. This method avoids the subjective end-point judgment of the measurement personnel in the current standard method. Especially when the sample itself has color, it can effectively reduce the difficulty of end-point judgment.

[0019] 3. This method integrates two detection items in one detection example. One original solution can measure two items, saving the detection time and improving the detection efficiency. Description of the Drawings

[0020] The present invention will be further described below in conjunction with the drawings and embodiments.

[0021] Figure 1 is a schematic structural diagram of one specific embodiment of the present invention. Detailed Embodiment

[0022] Now the present invention will be further described in detail in conjunction with the drawings. These drawings are all simplified schematic diagrams, only illustrating the basic structure of the present invention in a schematic manner, so they only show the components related to the present invention.

[0023] The following will further elaborate on the embodiments of the present invention in conjunction with the drawings:

[0024] If there are terms related to directional indications or positional relationships in the embodiments of this application (such as up, down, left, right, front, back, inside, outside, top, bottom, center, vertical, horizontal, longitudinal, transverse, length, width, counterclockwise, clockwise, axial, radial, circumferential, etc.), then such terms are only used to explain the relative positional relationships, motion conditions, etc. between components in a certain specific posture (as shown in the attached drawings); if this specific posture changes, then the directional indication or positional relationship also changes accordingly. In addition, terms such as "first" and "second" involved in the embodiments of this application are only for the purpose of convenient description and cannot be understood as indicating or implying relative importance.

[0025] As Figure 1 shown, a method for jointly testing the turbidity and oxygen consumption of feather and down of the present invention includes the following steps:

[0026] Step 1: Prepare about 1000 ml of sample solution according to the pre-treatment method of oxygen consumption in 5.4 of GB / T 10288-2016 "Inspection Methods for Feathers and Down".

[0027] Step 2: Take 100 ml of the sample solution and inject it into the measuring dish in the tester. The above-mentioned measuring dish is 10 cm long, 1 cm wide, and 15 cm high, with an open upper part, a transparent bottom and left and right sides, and opaque front and back sides. The material is quartz. (This measuring dish can be regarded as a cuvette of a spectrophotometer. Usually, quartz material is used, and optical glass material can also be used. The measuring dish made of quartz material has high hardness and strong wear resistance). The above-mentioned measuring dish is placed on the linear slide rail base and shaken by driving the linear slide rail base to move back and forth through a motor.

[0028] Step 3: Then vertically irradiate the composite light of (400 - 700) nm from the bottom of the measuring dish. The detector is above the measuring dish to measure the absorbance of the sample solution, and make an absorbance-visual value working curve for different sample solutions. The above-mentioned visual value is the turbidity value measured according to Method 5.5.3.1A (visual method) of GB / T10288-2016, with the unit of mm, and fit the regression equation of the absorbance-visual value working curve. Input the absorbance obtained by the above method into the regression equation to obtain the turbidity value of the sample.

[0029] Step 4: Add 100 ml of tertiary water into the above measuring dish, then add 2 ml of 3 mol / L sulfuric acid aqueous solution. The motor drives the measuring dish to move back and forth to mix the sample solution evenly. Dropwise add 0.020 mol / L potassium permanganate standard solution. When 0.020 ml, 0.080 ml, 0.160 ml, 0.200 ml, and 0.300 ml of the above potassium permanganate standard solution are added respectively, the measuring dish moves back and forth and shakes for 1 min. Then, emit visible light with a wavelength of 525 nm vertically from the right side of the measuring dish, and the detector is correspondingly arranged on the left side of the measuring dish. Measure the absorbance of the test solution and establish a working curve of absorbance and the volume of potassium permanganate standard solution, and fit to obtain the regression equation:

[0030] A = 0.3761V - 0.00402 (Equation 1)

[0031] Where: A is the absorbance,

[0032] V is the volume of the potassium permanganate standard solution added dropwise, in ml.

[0033] Step 5: Add 100 ml of sample solution into the above measuring dish, then add 2 ml of 3 mol / L sulfuric acid aqueous solution. The measuring dish moves back and forth to mix the sample solution evenly. Measure the absorbance A of the sample solution according to the method in Step 4 杂 . Dropwise add 0.200 ml of 0.020 mol / L potassium permanganate standard solution. After the measuring dish moves back and forth and shakes for 1 min, measure the absorbance A of the sample solution according to the method in Step 3 样 . A = A 样 - A 杂 . Substitute A into Equation (1) to obtain V, then the oxygen consumption of the sample = (0.2 - V) * 80, with the unit of mg / 100 g.

[0034] The regression equation of the absorbance-visual value working curve and the regression equation of the absorbance-potassium permanganate standard solution volume working curve for daily detection can be prepared in advance and can be reused within a certain period of time. In this way, the turbidity and oxygen consumption of the feather and down can be measured quickly and accurately.

[0035] The example equipment adopted in this application, for example Figure 1 , includes a sliding guide rail frame 10, a 525 nm light source 11, a 400 nm - 700 nm composite light source 12, a second detector 13, a first detector 14, an electric linear telescopic device 15, and a measuring dish 16. The measuring dish 16 is linearly slidably arranged on the sliding guide rail frame 10 and is driven by the electric linear telescopic device 15 to realize the front-back shaking of the measuring dish 16. The light path of the 400 nm - 700 nm composite light source 12 passes through the measuring dish 16 from bottom to top and is received and detected by the first detector 14. The light path of the 525 nm 11 passes through the measuring dish 16 from right to left and is received and detected by the second detector 13.

[0036] It should be emphasized that the embodiments described in the present invention are illustrative rather than restrictive. Therefore, the present invention is not limited to the embodiments described in the specific implementation manners. Any other implementation manners derived by those skilled in the art based on the technical solutions of the present invention also fall within the scope of protection of the present invention.

Claims

1. A method for jointly testing the turbidity and oxygen consumption of feather and down, characterized in that: It includes the following steps: Step 1: Prepare about 1000 ml of sample solution according to the pre-treatment method of oxygen consumption in GB / T 10288-2016 "Inspection Methods for Down and Feather". Step 2: Inject 100 ml of the sample solution into the measuring dish in the tester. The above-mentioned measuring dish is 10 cm long, 1 cm wide, and 15 cm high, with an open upper part, a transparent bottom and left and right sides, and opaque front and back sides. The above-mentioned measuring dish is placed on a linear slide rail base and shaken by driving the linear slide rail base to move back and forth by a motor. Step 3: Then vertically irradiate the compound light from the bottom of the measuring dish. The detector is above the measuring dish. Measure the absorbance of the sample solution and make an absorbance-visual value working curve for different sample solutions. The above-mentioned visual value is the turbidity value measured by the 5.5.3.1A method (visual method) in GB / T 10288-2016, with the unit of mm. Fit the regression equation of the absorbance-visual value working curve, and input the absorbance obtained by the above method into the regression equation to obtain the turbidity value of the sample. Step 4: Add 100 ml of tertiary water and 2 ml of 3 mol / L sulfuric acid aqueous solution to the above-mentioned measuring dish. The motor drives the measuring dish to move back and forth to mix the sample solution evenly. Dropwise add 0.020 mol / L potassium permanganate standard solution. When 0.020 ml, 0.080 ml, 0.160 ml, 0.200 ml, and 0.300 ml of the above-mentioned potassium permanganate standard solution are added respectively, the measuring dish moves back and forth and shakes for 1 min. Then vertically irradiate visible light from the right side of the measuring dish, and the detector is correspondingly arranged on the left side of the measuring dish. Measure the absorbance of the test solution and establish a working curve of absorbance and the volume of potassium permanganate standard solution, and fit the regression equation: A = 0.3761V - 0.00402 (Equation 1) where: A is the absorbance, V is the volume of the potassium permanganate standard solution added dropwise, with the unit of ml; The compound light in Step 3 is (400 - 700) nm compound light. Step 5: Add 100 ml of the sample solution into the above measuring dish, then add 2 ml of 3 mol / L sulfuric acid aqueous solution. Move the measuring dish back and forth to mix the sample solution evenly, and measure the absorbance A of the sample solution according to the method in Step 4. 杂， Dropwise add 0.200 ml of 0.020 mol / L potassium permanganate standard solution. After moving the measuring dish back and forth and shaking for 1 min, measure the absorbance A of the sample solution according to the method in Step 3. 样 , A = A 样 -A 杂 , Substitute A into Equation (1) to obtain V, then the oxygen consumption of the sample = (0.2 - V) * 80, with the unit of mg / 100 g.

2. The method for jointly testing the turbidity and oxygen consumption of feather and down according to claim 1, wherein: The visible light vertically irradiated from the right side of the measuring dish in Step 4 is 525 nm visible light.

3. A method for jointly testing the turbidity and oxygen consumption of feather and down, according to claim 1 or 2, characterized in that: The material of the above-mentioned measuring dish is glass or quartz, and an opaque tape is pasted on the surface where no detection light passes.

4. The method for jointly testing the turbidity and oxygen consumption of feather and down according to claim 3, characterized in that: ​

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