Some people think that: the cultivation of green vegetables can only be applied organic fertilizers, the application of chemical fertilizers does not meet the standards of green food. In fact, this is a misunderstanding of inorganic nitrogen sources that vegetables can directly absorb. Organic fertilizers, after being decomposed by microorganisms, can convert organic nitrogen into inorganic nitrogen. Finally, inorganic nitrogen is absorbed by vegetables. Therefore, as long as organic fertilization is used to increase soil fertility on the basis of chemical fertilizer application technology, insert leguminous crops to increase soil nitrogen content, reduce the use of chemical nitrogen fertilizers, strictly control nitrogen fertilization time, and control the nitrate content of the crop. Produce high quality green vegetables. Technically speaking, green vegetables should be used to fertilize the following points: Control the amount of nitrogen fertilizer. In order to ensure that green vegetables have better yield and economic benefits, it is necessary to apply nitrogen fertilizer properly on the basis of organic fertilizers, but it is necessary to control the dosage in order to solve the contradiction between quality and yield, yield and benefit. At the same time, attention was paid to the selection of nitrogen fertilizers. Nitrate accumulation in vegetables decreased with the effects of sodium nitrate, ammonium nitrate, urea, and ammonium chloride. Strictly grasp the top dressing time of nitrogen fertilizer. The nitrate content of vegetable crops is constantly changing. The nitrogen that enters the vegetable body is further converted to protein during metabolism. According to the study, nitrate content in vegetables gradually decreases with the increase of nitrogen fertilizer application time. After 18 days of topdressing, the nitrate content in the vegetables has met the green food recommendation standard. Therefore, the top dressing time of green vegetables should be 15-20 days before harvesting. Balanced fertilization. All kinds of fertilizers combined application, than the single application of nitrogen fertilizer can easily reduce the content of nitrate in vegetables. The combination of nitrogen and phosphorus and the application of trace fertilizer can reduce the nitrate content of vegetables, especially with potassium fertilizer, can promote protein synthesis and reduce the nitrate content in the body.
The Medical Drying Cabinet is a kind of large capacity medical drying equipment developed according to the requirements of the hospital.It is used to dry surgical instruments,glassware and respiratory treatment articles.Medical drying cabinet the operation is simple and flexible,the drying temperature setting range is 40 °C ~ 90 °C,and the drying time setting range is 1min ~ 999min.The user can freely set according to the demand.Medical drying cabinet the device has two specifications of single door and double door,which is suitable for different departments in the hospital.
Medical Drying Cabinet
Medical Drying Cabinet,Vertical Drying Cabinet,Metal Drying Cabinet,Plastic Drying Cabinet
Henan Sanqiang Medical Equipment Liability Co.,Ltd , http://www.sterilizers-china.com