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Regarding the quality requirements of decoctions, there should be no burnt smell, peculiar smell, and sugar-free crystal precipitation.
(1) Relative density check
1.
(1) Relative density refers to the ratio of the density of a substance to the density of a reference substance (water) under the same environmental conditions (such as the same temperature, etc.
(2) This method is applicable to the relative density inspection of decoctions, and the purpose is to control the density of decoctions to ensure the quality of medicines
(3) All decoctions with fine powder of decoction pieces should be checked before adding the powder, and the powder can be added only after it meets the requirements
2.
(1) Pycnometer (Figure 15-2)
1) Take an appropriate amount of the test product and place it in a weighed small beaker (select 30ml, 50ml or 100ml according to your needs), accurately weigh it, and measure with a graduated cylinder (25ml or 50ml) equivalent to 2 times the sample weight of the test product The volume of water is poured into the above small beaker, accurately weighed, and stirred with a glass rod as the test solution
2) Weighing the weight of the empty pycnometer: Wash and dry the pycnometer (choose 5ml, 10ml, 25ml or 50ml as needed), and weigh the empty pycnometer
3) Determination of the weight of the test product: Take the above-mentioned empty pycnometer with a fixed weight, fill it with the test product (the temperature should be lower than 20℃ or the temperature specified under each category), and insert the bottle with a pore in the center Plug, use filter paper to wipe dry the liquid overflowing from the plug hole, place it in a constant temperature water bath of 20℃ (or the temperature specified under each item) for a few minutes.
4) Determination of water weight: After obtaining the weight of the test product as described above, pour out the test product in the pycnometer, clean the pycnometer, fill it with freshly boiled cold water, and then follow the test method for determining the weight of the test product Measure the weight of water at the same temperature
5) When using a pycnometer with a thermometer, insert the thermometer (no bubbles in the bottle) after filling the test product, and place it in a constant temperature water bath at 20°C for several minutes until the temperature of the content reaches 20°C.
(2) Webster's specific gravity scale (Figure 15-3)
1) Take the Webster's specific gravity weighing with a relative density of 1 at 20°C, fill the attached glass cylinder with freshly boiled cold water to 80% full, and place it in a water bath at 20°C (or the temperature specified under each category) , Stir the water in the glass cylinder, adjust the temperature to 20°C (or the temperature specified under each item), immerse the glass hammer hanging on the weighing end into the water in the glass cylinder, and hang the Youma at 1.
2) If the specific gravity scale has a relative density of 1 at 4°C, the Yuma should be hung at 0.