Urea is a physiologically neutral fertilizer that does not leave any harmful substances in the soil and has no adverse effects on long-term application. However, when the temperature is too high in the granulation process, a small amount of biuret, also known as biuret, can inhibit the crop. China's urea biuret fertilizer content should be less than 0.5%. When the biuret content exceeds 1%, the seed fertilizer, seedling fertilizer, and foliar fertilizer cannot be used. The urea content during other application periods should not be too much or too concentrated. Urea is an organic nitrogen fertilizer that can be absorbed and utilized by crops after it is hydrolyzed into ammonium carbonate or ammonium bicarbonate through the action of urease in the soil. Therefore, urea should be applied 4-8 days before the crop's need for fertilizer. Application: Urea is suitable for basal and topdressing, and sometimes as a seed fertilizer. Before the transformation, urea is molecular and cannot be adsorbed by soil. It should be prevented from being lost with water. The ammonia formed after conversion is also volatile, so urea must be applied deeply. Urea is widely found in nature, such as fresh human feces containing 0.4% urea. Urea production accounts for about 40% of China's current total nitrogen fertilizer production. It is one of the major nitrogen fertilizers next to ammonium bicarbonate. As a nitrogen fertilizer, it began in the early 20th century. Since the 1950s, due to the high nitrogen content of urea (45% to 46%), extensive use, and continuous improvement of industrial processes, countries around the world have developed rapidly. China began to establish a medium-sized urea plant from the 1960s. From 1986 to 1992, China's urea production was over 9 million tons. At present, it accounts for 40% of the total nitrogen fertilizer production. Urea is a physiologically neutral fertilizer that does not leave any harmful substances in the soil and has no adverse effects on long-term application. However, when the temperature is too high in the granulation process, a small amount of biuret, also known as biuret, can inhibit the crop. China's urea biuret fertilizer content should be less than 0.5%. When the biuret content exceeds 1%, the seed fertilizer, seedling fertilizer, and foliar fertilizer cannot be used. The urea content of other application periods should not be too much or too concentrated. Urea is an organic nitrogen fertilizer that can be absorbed and utilized by crops after it is hydrolyzed into ammonium carbonate or ammonium bicarbonate through the action of urease in the soil. Therefore, urea should be applied 4-8 days before the crop's need for fertilizer. Application: Urea is suitable for basal and topdressing, and sometimes as a seed fertilizer. Before the transformation, urea is molecular and cannot be adsorbed by soil. It should be prevented from being lost with water. The ammonia formed after conversion is also volatile, so urea must be applied deeply. The use of urea: Urea is a commonly used available nitrogen fertilizer and has many other uses besides top dressing. Correct storage method 1. Urea is the fertilizer with the highest nitrogen content in solid nitrogen fertilizer. It has relatively stable physicochemical properties and no effect on soil properties after application. It can be applied to any soil and crops and can be used as a root fertilizer. At the same time, urea is also an important raw material for resins, plastics, explosives, pharmaceuticals, and food industries. 3. If urea is improperly stored, it will easily absorb hygroscopic agglomerates, affect the original quality of urea, and cause certain economic losses to the farmers. This requires the majority of farmers to properly store urea. Before use, be sure to keep the urea bags in good condition. Handle them gently during transportation and store them in a dry, well-ventilated place with a temperature below 20 degrees. We supply good variety yellow & red onions, fresh keeping. Advanced management plus careful cultivation, surely we have delicious and safe onions for every client. All our growing field registered at CIQ (China Entry-Exit Inspection And Quarantine Bureau) , we control farm chemicals from seeds to finished products. In the past over 20 years, no quality problem ever occurred. We can process and export 500tons of Fresh Onions per day with our ten onion sizing lines. Maximum exported quantity in June was more than ten thousand tons. Fresh Onions Fresh Onions,Fresh Red Onions,Fresh Cheap Onion,Fresh Yellow Onion Yirun Agricultural Cooperative , https://www.yiruncn.com
First, to adjust the amount of flowers In order to overcome the size of Apple, in the case of young years, 5-6 weeks after flowering (the critical period of apple flower bud differentiation, new shoots grow slowly or stop, the leaf nitrogen content showed a downward trend) leaf spray Application of 0.5% urea aqueous solution, even spraying 2 times, can increase leaf nitrogen content, speed up shoot growth inhibition of flower bud differentiation, so that the amount of flowers in the year is appropriate.
Second, the thinning and fruiting fruit trees are more sensitive to urea, but the surface reaction is less blunt. Therefore, foreign countries used urea to carry out fruiting and fruiting tests on peaches and nectarines. The results showed that the peach and nectarine sparsely As a result, a large concentration (7.4%) is required to show good results. The most suitable concentration is 8% to 12%. Within 1-2 weeks after spraying, the objective of thinning and fruit thinning can be achieved. However, under different land conditions, the reaction of different periods and different species still needs further tests.
III. Seed Production in Hybrid Rice In order to increase the outcrossing rate of parents in order to increase the seed production of hybrid rice or the breeding amount of sterile lines, the use of maternal parent spray to reduce the female parent The degree of wrapping the neck can be fully extracted; or spraying the parent's book, adjusting the growth of both to synchronize the flowering period. As gibberellic acid is more expensive, its cost for seed production is high. People experimented with urea instead of gibberellin, and used 1.5%-2% urea during the progesterone panicle and heading stage (20% heading). The effect of the multiplication was similar to that of gibberellin, and no increase in plant height was observed.
Fourth, pest control use urea, detergent, water 4:1:400, stir and stir, can prevent fruit trees, vegetables, cotton aphids, spider mites, cabbage caterpillars and other pests, insecticidal effect of 90% or more.
Five, urea iron fertilizer urea in the form of complexes, with iron chelate chelation. This organic iron fertilizer has a low cost, and it has a good effect in preventing iron deficiency and chlorosis. In addition, when 0.3% urea was added when 0.3% ferrous sulfate was sprayed on the leaves, the effect of preventing and controlling chlorosis was better than that of single-spraying 0.3% ferrous sulfate.
2. Urea can also partially replace protein feeds. For example, adding urea to dairy cow green fodder can replace part of the protein feed. However, the amount of urea added can exceed 3% of the green feed and 1% of the total feed, otherwise the livestock kidneys are overburdened. , easy to cause disease, soybean cake contains urease, do not mix with urea supply.
4, if it is a large number of storage, the following should use wood mats from about 20 cm, the upper and roof should have more than 50 cm of space, in order to facilitate the ventilation of the wet, between the ape and the axe to be left. To facilitate inspection and ventilation. If the urea that has been opened has not been used up, it must be sealed in time to facilitate the use of the next year.
Raw materials: natural gas, coal, and petroleum are the three major raw materials for producing chemical fertilizers. They are usually called gas heads, coal heads, and oil heads. In recent years, the increase in the prices of oil and coal is much larger than that of natural gas, so it is ranked by cost advantage. For the gas head, coal head, oil head. For example, the gas company Yuntianhua has a gross margin of 58%, while the coal head company Hualu Hengsheng has a gross margin of 20%.