When fertilizing crops, we must seize two critical periods: the nutritional critical period and the maximum nutrient efficiency period to achieve a multiplier effect. I. Critical period of nutrition refers to the fact that the absolute amount of fertilizer nutrient requirements for wheat is not large, but it is a period of very urgent need. If such nutrients are lacking at this time, the growth and development of the crop will be significantly affected, and the resulting loss will be difficult to recover or make up even if it is applied later. Phosphorus critical period of nutrients in wheat seedling stage, because the root system is still very weak, poor absorption capacity, so the need for phosphorus at the seedling stage is very urgent. The critical period of nitrogen nutrition is when vegetative growth turns to reproductive growth, and winter wheat is during the two stages of tillering and spikelet differentiation. The application of nitrogen fertilizer in the late growth stage can only increase the nitrogen content in the stems and leaves, and it has no obvious effect on increasing the number of grains per spike or increasing the yield. Second, the period of maximum nutrient efficiency refers to the period when wheat absorbs the largest amount of nutrients, has the fastest absorption rate, and has the highest fertility yield. The maximum nutrient efficiency of winter wheat is from jointing to heading, at which time it grows vigorously and its ability to absorb nutrients is strong. Fertilizers need to be topdressed in a timely manner to meet the greatest demand for nutrients from wheat and to obtain the best fertilization results. It is very important for the synthesis of polyurethane adhesives and sealants, which directly affects the mechanical properties and process In a broad sense, most of the weak reductants are antioxidants and are selected for different industrial USES. Weak reductants with high chemical and physical stability, or with low toxicity, can be skillfully used as antioxidants in formulations. For example, citric acid is a weakly reducing organic acid that can be used in beverage formulations to act as an antioxidant. Food is easy to oxidize and deteriorate for a long time, so a small amount of antioxidant can be added to prolong its storage time. High polymer materials such as plastic, synthetic fiber and rubber are prone to thermo-oxygen degradation. Adding antioxidant can maintain the excellent performance of high polymer materials and prolong their service life. Imported Premium Antioxidant,Pvc Premium Antioxidant,Ps Premium Antioxidant,Abs Resins Premium Antioxidant Xingbang High Molecular Materials Co., Ltd. , https://www.chemicaladditive.com