Method and equipment for identifying common mulberry leaves and industrial feed silkworm rearing raw silk

Abstract

The invention relates to the technical field of silk identification, in particular to a method for identifying common mulberry leaves and industrial feed silkworm rearing raw silk, which comprises the following steps: S1, cutting a sample to below 5mm; s2, performing thermal decomposition on the sheared sample to obtain the proportion of residual substances, and testing the sample by using a thermogravimetric analyzer under different atmosphere conditions and heating rate conditions; s3, drawing a curve graph, and obtaining a thermogravimetric curve of the sample by taking the thermal decomposition temperature as an abscissa and the mass residue percentage of the sample as an ordinate. According to the method, the essential difference of the common mulberry leaves and the silk for breeding silkworms with industrial feed in mineral substance residue is utilized, the mineral substance content of the raw silk produced by the silkworms fed with the feed is relatively high, and the content of the mineral substances is relatively high; the content of mineral substances in the raw silk produced by silkworms eating mulberry leaves is low, the mineral substances in the silk are derived from food, the addition amount of the mineral substances in feed is high, and the purpose of identifying the attributes of the raw silk is achieved by burning off organic matters in the raw silk and evaluating the proportion of inorganic ash residues.

Description

Technical Field

[0001] The invention relates to the technical field of silk identification, in particular to a method and equipment for identifying common mulberry leaves and raw silk from industrial feed for silkworms. Background Art

[0002] The modern silk industry has developed a parallel production model for traditional mulberry silk and new industrialized feed-reared silk. Traditional mulberry silk, which relies on natural mulberry leaves as a feedstock, has low production efficiency and is heavily dependent on seasons, labor, and land. Industrial feed-reared silkworms, on the other hand, utilize artificially formulated feed (primarily composed of soy protein, starch, minerals, and synthetic additives) to achieve high-density, year-round, all-weather breeding, significantly increasing production. However, feed-reared silk is inferior to mulberry leaf-reared silk in quality indicators such as fiber strength and cohesion, making it less suitable for high-end silk production. Feed-reared silkworms, which enable year-round factory-based production and consistent quality, may be the future trend in sericulture. While the market share of feed-reared silk continues to grow annually, there is a 20%-30% price difference between the two raw materials. As a result, some vendors are selling feed-reared silk as mulberry leaf-reared silk, impacting the market regulation and the quality of downstream products. Therefore, accurately distinguishing silk from mulberry leaf-reared and feed-reared silk has become a pressing issue for the silk industry.

[0003] Currently, the industry mainly relies on the following identification methods, but they all have significant flaws:

[0004] Morphological observation method: The fiber surface morphology was observed by scanning electron microscopy. Traditional mulberry silk showed continuous and smooth longitudinal grooves, while discrete protrusions (about 50-80nm in height) were visible on the surface of feed-reared silk. However, this method requires destroying the sample, and when the amount of mulberry leaf powder added to the feed is greater than 30%, the morphological difference is reduced to less than 5%, resulting in a misjudgment rate of up to 40%.

[0005] Near-infrared spectroscopy: Utilizing the difference in absorption peaks in the 850-2500nm band for analysis, feed-raised silk will exhibit a characteristic shoulder peak at 1450nm (originating from the stretching vibration of the C-H bonds in feed additives). However, this technology requires the establishment of a large database, and the detection accuracy for blended samples (such as mulberry silk / feed silk blends) is insufficient, with the minimum detection limit being only 15%.

[0006] The development of efficient and accurate silk identification technology is not only related to the fair trade of the industry worth over 10 billion yuan each year, but is also a key measure to standardize breeding models and protect consumer rights. The defects of existing methods in precise analysis have seriously restricted market supervision and high-end silk product certification.

[0007] Therefore, those skilled in the art have proposed a method and equipment for distinguishing raw silk from ordinary mulberry leaves and industrial feed to solve the above-mentioned problems. Summary of the Invention

[0008] Therefore, the technical problem to be solved by the present invention is to accurately distinguish the silk produced by silkworms raised on mulberry leaves from the silk produced by silkworms raised on feed.

[0009] The above technical problem is solved by the following technical solution: The present invention provides a method for distinguishing ordinary mulberry leaves and industrial feed silkworm raw silk, comprising the following steps:

[0010] S1. Cut the sample into pieces less than 5 mm;

[0011] S2. Thermally decompose the shredded samples to determine the proportion of residual substances, and test the samples using a thermogravimetric analyzer under different atmosphere conditions and heating rates;

[0012] S3. Draw a graph with the thermal decomposition temperature as the abscissa and the sample mass residual percentage as the ordinate to obtain the thermogravimetric curve of the sample. Draw a vertical line at the abscissa of the thermogravimetric curve at 175°C, and obtain the intersection of the vertical line and the thermogravimetric curve as point a. The ordinate value corresponding to point a is used as the dry weight percentage w0 of the fiber. Draw a vertical line at the abscissa of the thermogravimetric curve at 650°C, and obtain the intersection of the vertical line and the thermogravimetric curve as point b. The ordinate value corresponding to point b is used as the weight percentage w1 of the fiber decomposition residue.

[0013] S4. Determine the silk type of the sample. If w1 / w0>0.600%, the sample is determined to be raw silk from silkworms raised on industrial feed. If w1 / w0≤0.600%, the sample is determined to be raw silk from silkworms raised on ordinary mulberry leaves.

[0014] As a preferred embodiment of the method for identifying raw silk from common mulberry leaves and industrial feed for silkworms of the present invention, the atmosphere condition is air or oxygen.

[0015] As a preferred embodiment of the method for distinguishing raw silk from ordinary mulberry leaves and industrial feed for silkworms of the present invention, the heating rate is in the range of 5-20°C / min.

[0016] A device for distinguishing raw silk from ordinary mulberry leaves and industrial feed silkworms, using the method for distinguishing raw silk from ordinary mulberry leaves and industrial feed silkworms, further comprising:

[0017] The workbench serves as the overall support for the device;

[0018] a controller mounted on the workbench;

[0019] A silk fixing mechanism, mounted on the surface of the workbench, for fixing the silk;

[0020] A cutting mechanism is installed on one side of the workbench, with one end of the cutting mechanism being located directly above the silk fixing mechanism;

[0021] A thermogravimetric analyzer installed on one side of the workbench surface is used to thermally decompose the cut silk.

[0022] As a preferred embodiment of the device for distinguishing between ordinary mulberry leaves and industrial feed silkworm raw silk of the present invention, the silk fixing mechanism includes a fixing plate, which is installed on the surface of the workbench, and the surface of the fixing plate is provided with a plurality of longitudinal silk fixing grooves distributed at equal intervals, and the surface of the fixing plate is provided with a plurality of transverse cutting grooves distributed at equal intervals.

[0023] As a preferred solution of the equipment for distinguishing ordinary mulberry leaves and industrial feed silkworm raw silk of the present invention, the cutting mechanism includes a mounting frame, which is installed on the outer wall of the workbench close to the fixed plate, and an electric cylinder is installed on the top inner wall of the mounting frame, and the electric cylinder is located directly above the center of the surface of the fixed plate, and a horizontal plate is installed at the bottom end of the electric cylinder, and a plurality of horizontally arranged cutting blades are fixed at equal intervals on the bottom outer wall of the horizontal plate, and the cutting blades are located directly above the corresponding cutting grooves, and pressing components are provided on the front and rear outer walls of the horizontal plate.

[0024] As a preferred solution of the equipment for distinguishing ordinary mulberry leaves and industrial feed silkworm raw silk of the present invention, the pressing assembly includes a connecting plate, which is installed on the outer wall of one side of the horizontal plate, and a plurality of telescopic rods are installed on the bottom outer wall of the connecting plate, and a spring is provided inside the telescopic rod. The bottom end of the telescopic rod is installed with the same pressing plate, and a plurality of pressing blocks are installed on the bottom outer wall of the pressing plate, and the pressing blocks are located at the ends of the corresponding silk fixing grooves.

[0025] As a preferred embodiment of the equipment for identifying raw silk from ordinary mulberry leaves and industrial feed for silkworms of the present invention, the thermogravimetric analyzer includes a heater, an installation groove is provided on the outer wall of the workbench, the heater is fixed inside the installation groove, the surface of the heater is flush with the dial of the workbench, and heat dissipation nets are provided on both sides of the installation groove.

[0026] As a preferred solution of the device for distinguishing common mulberry leaves from industrial feed silkworm raw silk of the present invention, an analyzer is installed on the surface of the heater, and a sample cavity is installed on the surface of the analyzer.

[0027] Beneficial effects of the method and device for distinguishing raw silk from ordinary mulberry leaves and industrial feed for silkworm breeding:

[0028] The essential difference in mineral residues between silkworms raised on ordinary mulberry leaves and those raised on industrial feed is that raw silk produced by silkworms fed on feed has a higher mineral content, while raw silk produced by silkworms fed on mulberry leaves has a lower mineral content. The minerals in silk are derived from the food, while the amount of minerals added to the feed is higher. The purpose of identifying the properties of raw silk is to burn the organic matter in the raw silk and then evaluate the proportion of inorganic ash residue.

[0029] The testing method is simple and easy to use, and has low professional requirements for testers. The principle of identification is based on the proportion of mineral residues in raw silk from silkworms raised on ordinary mulberry leaves and raw silk from silkworms raised on industrial feed, which is the essential difference between the two. The identification results are highly accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings of the embodiments of the present invention. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Among them:

[0031] Figure 1 This is the thermogravimetric curve under the conditions of Example 1 of the method for identifying raw silk from ordinary mulberry leaves and industrial feed.

[0032] Figure 2 This is the thermogravimetric curve under the conditions of Example 2 of the method for identifying raw silk from ordinary mulberry leaves and industrial feed.

[0033] Figure 3 Thermogravimetric curves under the conditions of Example 3 for the method of identifying raw silk from ordinary mulberry leaves and industrial feed.

[0034] Figure 4 Thermogravimetric curves under the conditions of Example 4 of the method for identifying raw silk from ordinary mulberry leaves and industrial feed.

[0035] Figure 5 Schematic diagram of the overall structure of the equipment for distinguishing raw silk from ordinary mulberry leaves and industrial feed.

[0036] Figure 6 Schematic diagram of the cutting mechanism structure of the equipment for distinguishing ordinary mulberry leaves and industrial feed silkworm raw silk.

[0037] Figure 7 Schematic diagram of the partial structure of the equipment for distinguishing raw silk from ordinary mulberry leaves and industrial feed.

[0038] In the figure: 1. Workbench; 101. Mounting slot; 102. Heat dissipation net; 2. Controller; 3. Silk fixing mechanism; 301. Fixing plate; 302. Silk fixing slot; 303. Cutting slot; 4. Cutting mechanism; 401. Mounting frame; 402. Electric cylinder; 403. Horizontal plate; 404. Pressing assembly; 4041. Connecting plate; 4042. Telescopic rod; 4043. Pressing plate; 4044. Pressing block; 405. Cutting disc; 5. Thermogravimetric analyzer; 501. Heater; 502. Analyzer; 503. Sample chamber. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below with reference to specific embodiments and the accompanying drawings.

[0040] The terms used in the present invention are those commonly used in the art in view of the functions of the present invention, but these terms may vary according to the intentions of those skilled in the art, precedents, or new technologies in the art. In addition, specific terms may be selected by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the present invention. Therefore, the terms used in the specification should not be understood as simple names, but rather as the meanings of the terms and the overall description of the present invention.

[0041] Example 1

[0042] Reference Figure 1 , which is the first embodiment of the present invention, provides a method for distinguishing ordinary mulberry leaves from industrial feed silkworm raw silk, comprising the following steps:

[0043] S1. Cut the sample into pieces less than 5 mm;

[0044] S2. Thermally decompose the shredded samples to determine the proportion of residual substances, and test the samples using a thermogravimetric analyzer under different atmosphere conditions and heating rates;

[0045] S3. Draw a graph with the thermal decomposition temperature as the abscissa and the sample mass residual percentage as the ordinate to obtain the thermogravimetric curve of the sample. Draw a vertical line at the abscissa of the thermogravimetric curve at 175°C, and obtain the intersection of the vertical line and the thermogravimetric curve as point a. The ordinate value corresponding to point a is used as the dry weight percentage w0 of the fiber. Draw a vertical line at the abscissa of the thermogravimetric curve at 650°C, and obtain the intersection of the vertical line and the thermogravimetric curve as point b. The ordinate value corresponding to point b is used as the weight percentage w1 of the fiber decomposition residue.

[0046] S4. Determine the silk type of the sample. If w1 / w0>0.600%, the sample is determined to be raw silk from silkworms raised on industrial feed. If w1 / w0≤0.600%, the sample is determined to be raw silk from silkworms raised on ordinary mulberry leaves.

[0047] Specifically, the atmosphere is air or oxygen.

[0048] Furthermore, the range of the heating rate is 5-20°C / min.

[0049] The sample was cut into pieces less than 5 mm and tested using a thermogravimetric analyzer in an air atmosphere (by introducing air into the sample chamber at 20 mL / min) at a heating rate of 10°C / min. The thermogravimetric curve of the sample was obtained with the thermal decomposition temperature as the horizontal axis and the sample mass residual rate as the vertical axis. A vertical line was drawn from the horizontal axis of the thermogravimetric curve at 175°C, and the intersection point of the vertical line and the thermogravimetric curve was obtained (denoted as point a). The vertical coordinate value corresponding to point a was used as the dry weight percentage w0 of the fiber. A vertical line was drawn from the horizontal axis of the thermogravimetric curve at 650°C, and the intersection point of the vertical line and the thermogravimetric curve was obtained (denoted as point b). The vertical coordinate value corresponding to point b was used as the weight residual rate w1 of the fiber decomposition residue. The w1 / w0 value was then calculated, and the identity of the sample was determined based on the w1 / w0 value.

[0050] Result analysis: Sample No. 1 was blind tested under these conditions, and its thermogravimetric curve is shown in the attached figure. Figure 1 As shown. The w0 corresponding to this sample at 175°C is 90.937%, and the w1 corresponding to this sample at 650°C is 0.568%. w1 / w0 = 0.625%, satisfying w1 / w0>0.600%. This sample meets the conditions for being determined to be raw silk from silkworms raised on industrial feed. Therefore, this sample is determined to be raw silk from silkworms raised on industrial feed. After confirmation with the production unit of this sample, the determination result is completely correct (the raw silk samples used in the examples were collected from silk-making enterprises in Guangxi, Sichuan, Zhejiang and other places. The properties of the samples are known to the sample-supplying units but unknown to us. The samples are numbered Specimen No. 1 to Specimen No. 4).

[0051] Comparative Example 1: Sample No. 5 was tested under nitrogen atmosphere, replacing the air atmosphere described in Example 1. Other conditions remained unchanged. The corresponding w0 for this sample at 175°C was 91.012%, and the corresponding w1 at 650°C was 1.101%. Analysis revealed w1 / w0 = 1.210%, satisfying the ratio w1 / w0 > 0.600%. This sample met the criteria for industrial feed-raised raw silk and was therefore identified as such. Confirmation with the sample's manufacturer confirmed this identification to be incorrect, indicating that the sample was, in fact, conventional mulberry leaf-raised raw silk.

[0052] This is because in an atmosphere of inert gases such as nitrogen, the raw silk undergoes only partial thermal cracking rather than complete combustion, resulting in excessively high residue mass and, therefore, a high w1 / w0 value, leading to misjudgment.

[0053] Example 2

[0054] Reference Figure 2 This is the second embodiment of the present invention. Unlike the previous embodiment, the sample is cut into pieces less than 5 mm and tested using a thermogravimetric analyzer under air atmosphere conditions and a temperature increase rate of 6°C / min. The thermogravimetric curve of the sample is obtained with the thermal decomposition temperature as the horizontal coordinate and the sample mass residual rate as the vertical coordinate. A vertical line is drawn from the horizontal coordinate of the thermogravimetric curve at 175°C to obtain the intersection point of the vertical line and the thermogravimetric curve (denoted as point a). The vertical coordinate value corresponding to point a is used as the dry weight percentage w0 of the fiber. A vertical line is drawn from the horizontal coordinate of the thermogravimetric curve at 650°C to obtain the intersection point of the vertical line and the thermogravimetric curve (denoted as point b). The vertical coordinate value corresponding to point b is used as the weight residual rate w1 of the fiber decomposition residue. Then the w1 / w0 value is calculated, and the identity attribute of the sample is determined based on the w1 / w0 value.

[0055] Result analysis: Sample No. 2 was blind tested under these conditions, and its thermogravimetric curve is shown in the attached figure. Figure 2 As shown. The sample's w0 at 165°C is 90.491%, and its w1 at 650°C is 0.858%. w1 / w0 = 0.948%, satisfying w1 / w0 > 0.600%. This sample meets the criteria for industrially fed silk production, and is therefore determined to be industrially fed silk. Confirmation with the sample's manufacturer confirms this determination is correct.

[0056] Example 3

[0057] Reference Figure 3 This is the third embodiment of the present invention. Unlike the previous embodiment, the sample is cut into pieces less than 5 mm and tested using a thermogravimetric analyzer under oxygen atmosphere conditions and a temperature increase rate of 15°C / min. The thermogravimetric curve of the sample is obtained with the thermal decomposition temperature as the horizontal coordinate and the sample mass residual rate as the vertical coordinate; a vertical line is drawn at the horizontal coordinate of 175°C on the thermogravimetric curve to obtain the intersection point of the vertical line and the thermogravimetric curve (denoted as point a), and the vertical coordinate value corresponding to point a is used as the dry weight percentage w0 of the fiber; a vertical line is drawn at the horizontal coordinate of 650°C on the thermogravimetric curve to obtain the intersection point of the vertical line and the thermogravimetric curve (denoted as point b), and the vertical coordinate value corresponding to point b is used as the weight residual rate w1 of the fiber decomposition residue, and then the w1 / w0 value is calculated, and the identity attribute of the sample is determined based on the w1 / w0 value.

[0058] Result analysis: Sample No. 3 was blind tested under these conditions, and its thermogravimetric curve is shown in the attached figure. Figure 3As shown. The sample's w0 at 175°C is 91.694%, and its w1 at 650°C is 0.523%. w1 / w0 = 0.570%, which does not satisfy the requirement of w1 / w0 > 0.600%. This sample meets the criteria for identification as ordinary mulberry leaf-raised raw silk. Therefore, this sample is identified as ordinary mulberry leaf-raised raw silk. Confirmation with the sample's manufacturer confirms this identification is completely correct.

[0059] Example 4

[0060] Reference Figure 4 This is the third embodiment of the present invention. Unlike the previous embodiment, the sample is cut into pieces less than 5 mm and tested using a thermogravimetric analyzer under oxygen atmosphere conditions and a temperature increase rate of 20°C / min. The thermogravimetric curve of the sample is obtained with the thermal decomposition temperature as the horizontal coordinate and the sample mass residual rate as the vertical coordinate; a vertical line is drawn from the horizontal coordinate of the thermogravimetric curve at 175°C to obtain the intersection point of the vertical line and the thermogravimetric curve (denoted as point a), and the vertical coordinate value corresponding to point a is used as the dry weight percentage w0 of the fiber; a vertical line is drawn from the horizontal coordinate of the thermogravimetric curve at 650°C to obtain the intersection point of the vertical line and the thermogravimetric curve (denoted as point b), and the vertical coordinate value corresponding to point b is used as the weight residual rate w1 of the fiber decomposition residue, and then the w1 / w0 value is calculated, and the identity attribute of the sample is determined based on the w1 / w0 value.

[0061] Result analysis: Sample No. 4 was blind tested under these conditions, and its thermogravimetric curve is shown in the attached figure. Figure 4 As shown. The sample's w0 at 175°C is 90.717%, and its w1 at 650°C is 0.362%. w1 / w0 = 0.399%, which does not satisfy w1 / w0 > 0.600%. This sample meets the criteria for identification as ordinary mulberry leaf-raised raw silk. Therefore, this sample is identified as ordinary mulberry leaf-raised raw silk. Confirmation with the sample's manufacturer confirms this identification is completely correct.

[0062] In Comparative Example 2, the heating rate described in Example 4 was changed from 20°C / min to 28°C / min, with all other conditions remaining unchanged. Sample No. 6 was tested using these conditions. The corresponding w0 for this sample at 175°C was 93.203%, and the corresponding w1 at 650°C was 0.454%. Analysis revealed w1 / w0 = 0.487%, which does not satisfy the requirement of w1 / w0 > 0.600%. This sample met the criteria for identification as ordinary mulberry leaf-raised raw silk and was therefore identified as such. Confirmation with the sample's manufacturer confirmed that this identification was incorrect, indicating that the sample was, in fact, industrial feed-raised raw silk.

[0063] This is because under conditions of a higher heating rate, the raw silk sample is significantly delayed in heating, the actual temperature is lower than the sample cavity temperature, the water evaporation is delayed, and the obtained "w0" is actually greater than the dry weight of the fiber, resulting in a higher w1 / w0 and a misjudgment.

[0064] Example 5

[0065] A device for distinguishing raw silk from ordinary mulberry leaves and industrial feed silkworms, using the above method for distinguishing raw silk from ordinary mulberry leaves and industrial feed silkworms, further comprising:

[0066] Workbench 1, serving as the overall support of the device;

[0067] A controller 2 mounted on a workbench 1;

[0068] A silk fixing mechanism 3 is installed on the surface of the workbench 1 and is used to fix the silk;

[0069] The cutting mechanism 4 is installed on one side of the workbench 1, and one end of the cutting mechanism 4 is located directly above the silk fixing mechanism 3;

[0070] Thermogravimetric analyzer 5 installed on one side of the surface of workbench 1 is used to thermally decompose the cut silk.

[0071] Among them, the silk fixing mechanism 3 includes a fixing plate 301, which is installed on the surface of the workbench 1. The surface of the fixing plate 301 is evenly distributed with multiple longitudinal silk fixing grooves 302, and the surface of the fixing plate 301 is evenly distributed with multiple transverse cutting grooves 303.

[0072] Among them, the cutting mechanism 4 includes a mounting frame 401, which is installed on the outer wall of the workbench 1 close to the fixed plate 301. An electric cylinder 402 is installed on the top inner wall of the mounting frame 401. The electric cylinder 402 is located directly above the center of the surface of the fixed plate 301. A horizontal plate 403 is installed at the bottom end of the electric cylinder 402. A plurality of horizontally arranged cutting blades 405 are evenly distributed and fixed on the bottom outer wall of the horizontal plate 403. The cutting blades 405 are located directly above the corresponding cutting grooves 303. Pressing components 404 are provided on the front and rear outer walls of the horizontal plate 403.

[0073] Among them, the pressing component 404 includes a connecting plate 4041, which is installed on the outer wall of one side of the horizontal plate 403, and a plurality of telescopic rods 4042 are installed on the bottom outer wall of the connecting plate 4041. A spring is provided inside the telescopic rod 4042, and the bottom end of the telescopic rod 4042 is installed with the same pressing plate 4043, and a plurality of pressing blocks 4044 are installed on the bottom outer wall of the pressing plate 4043. The pressing blocks 4044 are located at the ends of the corresponding silk fixing grooves 302.

[0074] Furthermore, the thermogravimetric analyzer 5 includes a heater 501, an installation groove 101 is opened on the outer wall of the workbench 1, the heater 501 is fixed inside the installation groove 101, the surface of the heater 501 is flush with the dial of the workbench 1, and heat dissipation nets 102 are provided on both sides of the installation groove 101.

[0075] Furthermore, an analyzer 502 is installed on the surface of the heater 501 , and a sample chamber 503 is installed on the surface of the analyzer 502 .

[0076] During use, the silk to be tested is combed into parallel bundles, the pressing blocks 4044 on both sides are lifted, and then the silk bundle is placed in the silk fixing groove 3, and is pressed and fixed by the pressing blocks 404 on both sides. Then, the electric cylinder 402 is started, and the silk is cut by the cutting piece 405. After obtaining silk less than 5 mm, the sample cavity 503 is opened, and the silk is placed in the sample cavity 503. The heater 501 is started for heating. The test is carried out according to the methods of the above-mentioned embodiments 1 to 4. Finally, the final result is obtained, and the silk can be judged.

[0077] It will be appreciated that in the development of any actual embodiment, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort may be complex and time-consuming, but will, for those of ordinary skill having the benefit of this disclosure, be a routine undertaking of design, fabrication, and production without undue experimentation.

[0078] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for distinguishing raw silk from ordinary mulberry leaves and industrial feed, characterized by: The following steps are involved: S1. Cut the sample into pieces less than 5 mm; S2. Thermally decompose the shredded samples to determine the proportion of residual substances, and test the samples using a thermogravimetric analyzer under different atmosphere conditions and heating rates; S3. Draw a graph with the thermal decomposition temperature as the abscissa and the sample mass residual percentage as the ordinate to obtain the thermogravimetric curve of the sample. Draw a vertical line at the abscissa of the thermogravimetric curve at 175°C, and obtain the intersection of the vertical line and the thermogravimetric curve as point a. The ordinate value corresponding to point a is used as the dry weight percentage w0 of the fiber. Draw a vertical line at the abscissa of the thermogravimetric curve at 650°C, and obtain the intersection of the vertical line and the thermogravimetric curve as point b. The ordinate value corresponding to point b is used as the weight percentage w1 of the fiber decomposition residue. S4. Determine the silk type of the sample. If w1 / w0>0.600%, the sample is determined to be raw silk from silkworms raised on industrial feed. If w1 / w0≤0.600%, the sample is determined to be raw silk from silkworms raised on ordinary mulberry leaves.

2. The method for distinguishing between ordinary mulberry leaves and industrial feed silkworm raw silk according to claim 1, characterized in that: The atmospheric condition is air or oxygen.

3. The method for distinguishing raw silk from ordinary mulberry leaves and industrial feed according to claim 2, characterized in that: The range of the heating rate is 5-20°C / min.

4. An apparatus for distinguishing raw silk from ordinary mulberry leaves and industrial feed, characterized by: The method for distinguishing raw silk from ordinary mulberry leaves and industrial feed according to any one of claims 1 to 3 further comprises: A workbench (1) serving as the overall support for the device; A controller (2) mounted on the workbench (1); A silk fixing mechanism (3) is installed on the surface of the workbench (1) and is used to fix the silk; A cutting mechanism (4) is installed on one side of the workbench (1), and one end of the cutting mechanism (4) is located directly above the silk fixing mechanism (3); A thermogravimetric analyzer (5) installed on one side of the surface of the workbench (1) is used to thermally decompose the cut silk.

5. The device for distinguishing between ordinary mulberry leaves and industrial feed silkworm raw silk as claimed in claim 4, characterized in that: The silk fixing mechanism (3) comprises a fixing plate (301), the fixing plate (301) being mounted on the surface of the workbench (1), the surface of the fixing plate (301) being provided with a plurality of longitudinal silk fixing grooves (302) distributed at equal intervals, and the surface of the fixing plate (301) being provided with a plurality of transverse cutting grooves (303) distributed at equal intervals.

6. The device for distinguishing between ordinary mulberry leaves and industrial feed silkworm raw silk as claimed in claim 5, characterized in that: The cutting mechanism (4) comprises a mounting frame (401), the mounting frame (401) being mounted on an outer wall of one side of the workbench (1) close to the fixed plate (301), an electric cylinder (402) being mounted on the top inner wall of the mounting frame (401), the electric cylinder (402) being located directly above the center of the surface of the fixed plate (301), a transverse plate (403) being mounted on the bottom end of the electric cylinder (402), a plurality of transversely arranged cutting blades (405) being fixed at equal intervals on the bottom outer wall of the transverse plate (403), the cutting blades (405) being located directly above the corresponding cutting grooves (303), and pressing components (404) being disposed on both the front and rear outer walls of the transverse plate (403).

7. The device for distinguishing between ordinary mulberry leaves and industrial feed silkworm raw silk as claimed in claim 6, characterized in that: The pressing assembly (404) includes a connecting plate (4041), which is installed on the outer wall of one side of the horizontal plate (403), and a plurality of telescopic rods (4042) are installed on the bottom outer wall of the connecting plate (4041), and a spring is provided inside the telescopic rod (4042). The bottom end of the telescopic rod (4042) is installed with the same pressing plate (4043), and a plurality of pressing blocks (4044) are installed on the bottom outer wall of the pressing plate (4043), and the pressing blocks (4044) are located at the ends of the corresponding silk fixing grooves (302).

8. The device for distinguishing between ordinary mulberry leaves and industrial feed silkworm raw silk as claimed in claim 7, characterized in that: The thermogravimetric analyzer (5) includes a heater (501), an installation groove (101) is provided on the outer wall of the workbench (1), the heater (501) is fixed inside the installation groove (101), the surface of the heater (501) is flush with the dial of the workbench (1), and heat dissipation nets (102) are provided on both sides of the installation groove (101).

9. The device for distinguishing between ordinary mulberry leaves and industrial feed silkworm raw silk as claimed in claim 8, characterized in that: An analyzer (502) is installed on the surface of the heater (501), and a sample chamber (503) is installed on the surface of the analyzer (502).

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