Abstract: A method of preparing an oxidized starch haemostatic material, including adding a starch raw material to an external circulation pulsatile reactor; switching on a pump to allow inflow of dry air for drying the raw material; switching on a heat exchanger; vacuumizing the reactor; opening a nitrogen dioxide pipeline and a dry air pipeline; pumping in a mixed gas; controlling temperature at 0-120° C. by the heat exchanger; wherein nitrogen dioxide is contacted with the raw material to trigger a selective oxidation reaction and is continuously recycled; an airflow circulation switch is switched on and off at a pulsating ratio of 1:1-10 to carry out airflow pulsation; stopping inflow of nitrogen dioxide and continuing airflow circulation for 5-30 minutes; after completion of the reaction, adjusting to room temperature; vacuumizing the reactor and treating exhaust gas; allowing nitrogen gas to flow in for rinsing the replaced reactor until completion.

Abstract: A pearl grading method includes the following steps: (1) determining the color type of the pearl to be graded; (2) generating a simulated three-dimensional graph of the pearl to be graded; (3) calculating roundness, so as to obtain a roundness grade; (4) calculating the diameter of the simulated three-dimensional graph, so as to obtain a diameter grade; (5) drawing an illumination-wavelength reflection spectrum; (6) changing a detected part, and drawing an illumination-wavelength reflection spectrum again; (7) repeating the step (6) for at least two times; (8) performing weighted average to obtain a correction curve; and (9) comparing the correction curve with each glossiness grade spectrum baseline, so as to determine a glossiness grade according to the spectrum baseline with the highest coincidence degree. The method has the beneficial effects of low cost, high speed, good result consistency and high detection precision.

Abstract: Disclosed is a method for preparing an oxidized cellulose hemostatic product, including using a sodium hydroxide solution with the concentration of 1 to 5% to pre-process a cellulose product; after removing lignins or impurities on the fiber surface, using an alkaline solution to activate the fiber surface further; after the activating treatment, using demin-water for washing until it is neutral and drying the obtained cellulose product in air to obtain a raw material; using a sodium hydroxide solution with the concentration of 5 to 20% as a solvent; adding the cellulose product, carbamide and ZnO that are 3 to 10%, 2% and 2% of the sodium hydroxide solution respectively.

Abstract: A pearl grading method includes the following steps: (1) determining the color type of the pearl to be graded; (2) generating a simulated three-dimensional graph of the pearl to be graded; (3) calculating roundness, so as to obtain a roundness grade; (4) calculating the diameter of the simulated three-dimensional graph, so as to obtain a diameter grade; (5) drawing an illumination-wavelength reflection spectrum; (6) changing a detected part, and drawing an illumination-wavelength reflection spectrum again; (7) repeating the step (6) for at least two times; (8) performing weighted average to obtain a correction curve; and (9) comparing the correction curve with each glossiness grade spectrum baseline, so as to determine a glossiness grade according to the spectrum baseline with the highest coincidence degree. The method has the beneficial effects of low cost, high speed, good result consistency and high detection precision.