GB/T 14593-2026Quantitative analysis of animal fibres such as cashmere and wool (English PDF)

4.2 Reagents, Instruments and Equipment

4.2.1 Scanning Electron Microscope. Functional requirements of a scanning electron microscope.

a) It consists of a vacuum system, an electro-optical system, a signal acquisition and imaging system, a display system, and measurement software;

b) Image acquisition mode. Secondary electronic image;

c) Operating voltage. 1kV~10kV;

d) Beam current. less than 5.0 × 10^-6 A;

e) Secondary electron image resolution >= 20nm;

f) Magnification. 30x to 10000x.

4.2.2 Vacuum sputtering or ion sputtering apparatus, with gold (Au) or platinum (Pt) as the target. If the sample has no charge effect under the working voltage, further processing is not required. Spray plating treatment.

4.2.3 Glass test tubes with a diameter of 10mm~15mm and stirring rods with a diameter of about 1mm.

4.2.4 A rectangular or square glass plate with a side length of about 15cm.

4.2.5 Acetone or ethyl acetate (analytical grade). This reagent is harmful to the human body; appropriate protective measures should be taken when using it.

4.2.6 Specimen holder. Specimen holder with a diameter of not less than 10 mm or other specimen holder that meets the test requirements.

4.2.7 Conductive double-sided tape.

4.2.8 Electronic balance, scale division

0.1 mg.

4.2.9 Hastings slicer or other types of fiber slicers.

4.3 Sample

4.3.1 Sample conditioning Test samples should be conditioned in the standard atmosphere specified in GB/T 6529 for at least 4 hours.

4.3.2 Sampling For loose fiber samples, lay the sample flat on the test bench and randomly select approximately 500 mg from both sides (at least 20 points) using tweezers. The samples were mixed and divided into three portions. Two portions were tested independently by two different operators, and one portion served as a backup sample. The three portions were then manually prepared. Fiber bundles that are basically parallel to each other.

4.4.1 Cut a fiber fragment of approximately

0.4 mm from each test sample using a slicer. Each sample should be cut only once and should not be repeated. Cut.

4.4.2 Place all the fiber fragments into a glass test tube, add 1 mL to 2 mL of acetone or ethyl acetate, stir well, and then pour into the prepared solution. On a good glass plate, the suspension is distributed within a 10cm diameter area.

4.4.3 Apply the double-sided conductive adhesive to the sample holder. After the reagent on the glass plate has evaporated, gently press the sample holder onto the glass plate. (The text abruptly ends here, likely due to an incomplete sentence or missing information.) The fibers on the glass plate are aggregated, and a new sample should be prepared.

4.4.4 Five sample holders shall be made for each sample and tested as a group.

4.4.5 Apply a gold film to the sample holder containing fiber fragments using a vacuum sprayer or ion sputtering apparatus.

4.5 Testing

4.5.1 Place the sample holder into the scanning electron microscope sample chamber. At a lower magnification, select the upper left corner as the observation starting point and choose an appropriate magnification. Observe the fiber images, generally at 500x to 8000x magnification, and identify the fiber type based on the fiber appearance and structural characteristics (see Appendix A).

4.5.2 After the fiber test at the selected location is completed, move the sample holder vertically or horizontally to scan the entire sample holder.

4.5.3 If only one type of fiber is found after testing.200 fibers in the first sample holder, at least 300 fibers should be tested in the second sample holder. If no second type of fiber is found, the sample can be considered a single component, and other sample holders can be discontinued. If two types of fibers are found, the sample can be considered a single component. If the sample is considered to be a mixed fiber, then at least.200 fibers should be tested in each remaining sample holder, and at least 1000 fibers should be tested in each sample. fiber.

4.5.4 For mixed fibers, the diameter of 24 fibers of each component were measured on a single specimen holder (if less than 24 fibers, all were measured). The diameter of a total of 120 fibers was measured in the sample. If the total number of fibers in a certain component is less than 120, the average number of fibers is calculated based on the actual number measured. diameter.

4.5.5 The five sample holders in the second group were analyzed in accordance with the requirements of

4.6 Treatment of coarse wool fibers For cashmere with a fiber diameter greater than 30µm, yak wool with a fiber diameter greater than 35µm, camel wool with a fiber diameter greater than 40µm, and rabbit wool with a fiber diameter greater than 30µm... Wool fibers were designated as goat hair, yak hair, camel hair, and coarse rabbit hair, respectively. The number of these coarse wool fibers accounted for a small proportion of the total number of fibers tested in the sample. At 0.3%, it is negligible.

4.7 Result Calculation

4.7.3 When the difference between the results of two samples does not exceed 3%, report the average of the two sets of results; when the difference exceeds 3%, take a backup sample for the second test. Three sets of tests were conducted, and the average of the three test results was reported. The rabbit hair mass fraction is the sum of the mass fractions of fine hair fibers and coarse hair fibers.

4.7.4 Test results shall be rounded to one decimal place in accordance with GB/T 8170.

5.2 Reagents, Instruments and Equipment

5.2.1 Optical Microscope. An optical microscope should have at least the following functions.

a) The objective lens and eyepiece should provide a total magnification of at least 500x;

b) A micrometer scale with a graduation of

0.01 mm should be provided for calibrating the instrument's magnification.

5.2.2 Liquid paraffin, analytical grade (refractive index between

5.2.3 Watch glass.

5.2.4 Electronic balance, scale division

0.1 mg.

5.2.5 Hasch slicer or other types of fiber slicers.

5.3 Sample The humidification and sampling of samples obtained by optical microscope imaging shall be performed in accordance with 4.3.

5.4.1 Use a slicer or double blade to cut a fiber fragment approximately

0.6 mm in length from the middle of the sample. Only one cut should be made per sample. Repeat the cutting process.

5.4.2 Place all fiber fragments on a petri dish, add an appropriate amount of liquid paraffin, and stir with tweezers to distribute them evenly in the medium. Then... Place an appropriate amount of sample on a glass slide, cover it with a coverslip, and be careful not to let the medium squeeze out from under the coverslip to avoid fiber loss.

5.5 Test

5.5.1 Place the glass slide containing the sample on the microscope stage and magnify it 500 times. Adjust the focus to the most suitable clarity and begin observation from the upper left corner. Based on the fiber appearance characteristics and structure (see Appendix C), the fibers in the field of view are qualitatively identified and their types are recorded.

5.5.2 If the sample contains two or more types of fibers, classify the fibers in the field of view and measure the fiber diameter according to GB/T 10685. The diameter of each fiber should be measured at least 300 fibers. If the number of fibers in a certain component is less than 300, then all fibers of that type on the slide should be measured. The diameter of the number of fibers. At least 1500 fibers are tested in each sample.

5.5.3 If the number of counted fibers reaches 1500 and the slide has only moved to the middle position, the counting should continue until the edge is reached before stopping.

5.5.4 The treatment of coarse fibers in the sample shall be calculated according to the requirements of 4.6.

5.6 Result Calculation

5.6.1 The average diameter and standard deviation of each component fiber in optical microscopy are calculated according to formulas (4) and (5).

5.6.2 The fiber mass fraction of each component of the sample, the reporting of results, and the rounding of test results shall be performed in accordance with the requirements of

6.Test Report The test report should include at least the following information.

a) Sample description;

b) The detection method used (scanning electron microscopy/optical microscopy);

c) The number of test fibers and the number of count fibers for each type;

d) Mean diameter and standard deviation of each fiber;

e) Mass fraction of each fiber;

f) Any details that deviate from this method;

g) Reporting and testing time.