Abstract: Provided in the present application are a composition for detecting occult blood in excreta, and a preparation method therefor and the use thereof. The composition comprises, in parts by weight, 20-80 parts of organic solvent, 0.01-50 parts of thickener, 0.01-2 parts of benzidine, 0.01-5 parts of peroxide, 0.001-0.5 parts of EDTA-2Na and 10-80 parts of water. The composition provided in the present application can quickly and effectively detect the occult blood condition of excreta, has fast color change, long color retention time and high sensitivity.

Abstract: Embodiments the invention disclose a cutting wheel, which includes: a wheel body; and a plurality of teeth formed on the wheel body, wherein each of the teeth includes a first auxiliary edge, a main edge and a second auxiliary edge that connect with each other successively. The main edge, the first auxiliary edge and the second auxiliary edge lie in the same plane, and inclined surfaces for forming the main edge, the first auxiliary edge and the second auxiliary edge respectively and located at the same side of the plane connect with each other successively. A recessed region is formed between main edges of two adjacent teeth, and a first auxiliary edge of one of the two adjacent teeth and a second auxiliary edge of the other of the two adjacent teeth are located within the recessed region.